EPA-420-R-14-004

February 2014

Summary and Analysis of Comments for

Control of Air Pollution from Motor Vehicles:

Tier 3 Motor Vehicle Emission and Fuel Standards

Assessment and Standards Division

Office of Transportation and Air Quality

U.S. Environmental Protection Agency
i

Index of Tier 3 Proposal Commenters

Commenter Abbreviation Docket ID Number

A 2nd Opinion Inc. EPA-HQ-OAR-2011-

0135-4684

Advanced Biofuels Association AFBA EPA-HQ-OAR-2011-

0135-4318

Advanced Biofuels USA AFBUSA EPA-HQ-OAR-2011-

0135-4357

Advanced Engine Systems Institute AESI EPA-HQ-OAR-2011-

0135-47311

Afton Chemical Corporation EPA-HQ-OAR-2011-

0135-4359

Algenol Biofuels, Inc. EPA-HQ-OAR-2011-

0135-4325, 4358

Alliance of Automobile Manufacturers Alliance EPA-HQ-OAR-2011-

0135-4461

American Academy of Pediatrics et al. EPA-HQ-OAR-2011-

0135-4760

American Coalition for Ethanol ACE EPA-HQ-OAR-2011-

0135-4313

American Council on Renewable Energy ACORE EPA-HQ-OAR-2011-

0135-4808, 4892

American Energy Alliance (coordinated 

comments2)

EPA-HQ-OAR-2011-

0135-4887

American Fuel & Petrochemical 

Manufacturers

AFPM EPA-HQ-OAR-2011-

0135-1374, 4276, 4730, 

4922, 4923

American Gas Association AGA EPA-HQ-OAR-2011-

0135-4303, 4306

American Lung Association ALA EPA-HQ-OAR-2011-

0135-4765, 4920

American Lung Association (coordinated 

comments)

ALA EPA-HQ-OAR-2011-

0135-4885, 0668, 4620, 

4810

American Lung Association, District of 

Columbia

EPA-HQ-OAR-2011-

0135-4175

American Lung Association in Greater 

Chicago

EPA-HQ-OAR-2011-

0135-4278

American Lung Association in 

Massachusetts, et al.

EPA-HQ-OAR-2011-

0135-4732

American Lung Association Lehigh 

Valley, PA

EPA-HQ-OAR-2011-

0135-3194

American Lung Association Maryland EPA-HQ-OAR-2011-

0135-4174
ii

American Lung Association North 

Carolina

EPA-HQ-OAR-2011-

0135-4177

American Lung Association South 

Central Pennsylvania

EPA-HQ-OAR-2011-

0135-3452, 3453, 3469

American Lung Association Virginia EPA-HQ-OAR-2011-

0135-4173

American Lung Association, Regional 

Leadership Council in Northeast Ohio

EPA-HQ-OAR-2011-

0135-4890

American Motorcyclist Association AMA EPA-HQ-OAR-2011-

0135-4880

American Petroleum Institute API EPA-HQ-OAR-2011-

0135-4276, 4922, 4923

American Thoracic Society EPA-HQ-OAR-2011-

0135-47303

American Trucking Association ATA EPA-HQ-OAR-2011-

0135-4731

Americas Petroleum Regional Technical 

Committee

APTRC EPA-HQ-OAR-2011-

0135-4292, 4916

Appalachian Mountain Club AMC EPA-HQ-OAR-2011-

0135-4452

Association of Global Automakers Global EPA-HQ-OAR-2011-

0135-4461

Aston Martin Lagonda Ltd. EPA-HQ-OAR-2011-

0135-4262

Attorney General of Connecticut, et. al. EPA-HQ-OAR-2011-

0135-4783

Attorney General of New York, et. al. EPA-HQ-OAR-2011-

0135-4689

Automotive Aftermarket Industry 

Association

AAIA EPA-HQ-OAR-2011-

0135-4300

Automotive Specialty Products Alliance ASPA EPA-HQ-OAR-2011-

0135-4268

Biotechnology Industry Organization BIO EPA-HQ-OAR-2011-

0135-4454

BlueGreen Alliance EPA-HQ-OAR-2011-

0135-4730

BMW of North America, LLC EPA-HQ-OAR-2011-

0135-4297

Boulder County Board of County

Commissioners

EPA-HQ-OAR-2011-

0135-4809

Boulder County Board of Health EPA-HQ-OAR-2011-

0135-4809

BP Products North America Inc. BP EPA-HQ-OAR-2011-

0135-4682

Business for Innovative Climate and 

Energy Policy

BICEP EPA-HQ-OAR-2011-

0135-3467
iii

California Air Resources Board CARB EPA-HQ-OAR-2011-

0135-4261, 4919

Care 2 (coordinated comments) EPA-HQ-OAR-2011-

0135-2679

Ceres Investor Network on Climate Risk EPA-HQ-OAR-2011-

0135-4295

Chesapeake Bay Foundation EPA-HQ-OAR-2011-

0135-1145

Chevron Products Company EPA-HQ-OAR-2011-

0135-4758

Chicago Metropolitan Agency for 

Planning

EPA-HQ-OAR-2011-

0135-4291

Children’s Environmental Health 

Network 

CEHN EPA-HQ-OAR-2011-

0135-4780

Chrysler Group LL EPA-HQ-OAR-2011-

0135-4326

CHS, Inc. EPA-HQ-OAR-2011-

0135-4891

City of Philadelphia Department of 

Public Health Management Services

EPA-HQ-OAR-2011-

0135-4730

Clean Air Council EPA-HQ-OAR-2011-

0135-4730

Clean Air Watch EPA-HQ-OAR-2011-

0135-4730

Clean Fuels Development Coalition CFDC EPA-HQ-OAR-2011-

0135-4690

Coordinated comments EPA-HQ-OAR-2011-

0135-2753, 2763, 2776, 

3197, 4254, 4255

Concerned Citizens Around Murphy EPA-HQ-OAR-2011-

0135-3196

Consumer Specialty Products 

Association

CSPA EPA-HQ-OAR-2011-

0135-4268

Consumers Union EPA-HQ-OAR-2011-

0135-4602

Consumers Union (coordinated 

comments)

EPA-HQ-OAR-2011-

0135-4600

CountryMark Cooperative EPA-HQ-OAR-2011-

0135-4781

Cummins Inc. EPA-HQ-OAR-2011-

0135-4309, 4464

Delaware Department of Natural 

Resources

DNRC EPA-HQ-OAR-2011-

0135-4685

Department of Defense Clean Air Act 

Services Steering Committee

EPA-HQ-OAR-2011-

0135-4274

Dresser Trap Rock, Inc. EPA-HQ-OAR-2011-
iv

0135-3591

Earthjustice (coordinated comments)

E.I. du Pont de Nemours and Company EPA-HQ-OAR-2011-

0135-4301

Emissions Control Technology 

Association

ECTA EPA-HQ-OAR-2011-

0135-4263, 4267, 4293

Energy Future Coalition and Urban Air 

Initiative

EPA-HQ-OAR-2011-

0135-4353

Environment America (coordinated 

comments)

EPA-HQ-OAR-2011-

0135-2685

Environmental Defense Fund EDF EPA-HQ-OAR-2011-

0135-4355

Environmental Justice Leadership Forum 

on Climate Change

EPA-HQ-OAR-2011-

0135-4730

Environmental Law and Policy Center ELPC EPA-HQ-OAR-2011-

0135-4731

Evangelical Environmental Network

(coordinated comments)

EPA-HQ-OAR-2011-

0135-4683

ExxonMobil EPA-HQ-OAR-2011-

0135-4307

Ferrari EPA-HQ-OAR-2011-

0135-4277

Flint Hills Resources, LP FHR EPA-HQ-OAR-2011-

0135-4287

Ford Motor Company EPA-HQ-OAR-2011-

0135-4349

General Motors LLC GM EPA-HQ-OAR-2011-

0135-4288

Governors’ Biofuels Coalition EPA-HQ-OAR-2011-

0135-4252

Growth Energy EPA-HQ-OAR-2011-

0135-4681

HEAL Utah EPA-HQ-OAR-2011-

0135-4453

HEAL Utah, Utah State Legislators EPA-HQ-OAR-2011-

0135-4455

Hyundai Motor Group EPA-HQ-OAR-2011-

0135-4731

Independent Fuel Terminal Operators 

Association

IFTOA EPA-HQ-OAR-2011-

0135-4310

INEOS Bio EPA-HQ-OAR-2011-

0135-4691

Institute for Energy Research IER EPA-HQ-OAR-2011-

0135-3195

International Council on Clean 

Transportation

ICCT EPA-HQ-OAR-2011-

0135-4304, 4917
v

International Federation of Inspection 

Agencies

IFIA EPA-HQ-OAR-2011-

0135-4292, 4916

Irving Oil Terminals Inc. EPA-HQ-OAR-2011-

0135-4260

Johnson Matthey EPA-HQ-OAR-2011-

0135-4730

Kentucky Division for Air Quality EPA-HQ-OAR-2011-

0135-4243

Kinder Morgan Transmix Company, 

LLC

EPA-HQ-OAR-2011-

0135-4893

League of Conservation Voters 

(coordinated comments)

EPA-HQ-OAR-2011-

0135-4257

Lotus Cars Ltd. EPA-HQ-OAR-2011-

0135-4687

Magellan Midstream Partners, L.P. EPA-HQ-OAR-2011-

0135-4284, 4688, 4926

Manufacturers of Emission Controls 

Association

MECA EPA-HQ-OAR-2011-

0135-4675, 4899

Marathon Petroleum Company LP MPC EPA-HQ-OAR-2011-

0135-4302

Maryland Department of the 

Environment

EPA-HQ-OAR-2011-

0135-4253

Maryland Department of Transportation EPA-HQ-OAR-2011-

0135-4881

MathPro EPA-HQ-2001-0135-

4730

McLaren Automotive Limited EPA-HQ-OAR-2011-

0135-4803

Medical Advocates for Healthy Air EPA-HQ-OAR-2011-

0135-4266

Mercatus Center at George Mason 

University

EPA-HQ-OAR-2011-

0135-4280

Mercedes-Benz USA, LLC on behalf of 

Daimler AG

EPA-HQ-OAR-2011-

0135-4676

Metropolitan Washington Air Quality 

Committee

MWAQC EPA-HQ-OAR-2011-

0135-4055

Michigan Department of Environmental 

Quality

MDEQ EPA-HQ-OAR-2011-

0135-4883

Mid-Atlantic Regional Air Management 

Association Inc.

MARAMA EPA-HQ-OAR-2011-

0135-4246

Mid-Continental Energy MCE EPA-HQ-OAR-2011-

0135-4807

Mitsubishi Motors R&D America, Inc MRDA EPA-HQ-OAR-2011-

0135-4281

Monroe Energy, LLC EPA-HQ-OAR-2011-

0135-4678
vi

Motor & Equipment Manufacturers 

Association

MEMA EPA-HQ-OAR-2011-

0135-4324

National Association of Clean Air 

Agencies

NACAA EPA-HQ-OAR-2011-

0135-4275

National Association of Convenience 

Stores

NACS EPA-HQ-OAR-2011-

0135-4327

National Automobile Dealers 

Association

NADA EPA-HQ-OAR-2011-

0135-4351

National Biodiesel Board NBB EPA-HQ-OAR-2011-

0135-4312

National Corn Growers Association NCGA EPA-HQ-OAR-2011-

0135-4285

National Marine Manufacturers 

Association

NMMA EPA-HQ-OAR-2011-

0135-4294

National Propane Gas Association NPGA EPA-HQ-OAR-2011-

0135-3200, 4354, 4692

Natural Resources Defense Council NRDC EPA-HQ-OAR-2011-

0135-4286

Natural Resources Defense Council

(coordinated comments)

EPA-HQ-OAR-2011-

0135-2775

Navigant Economics EPA-HQ-OAR-2011-

0135-4731

New York State Department of 

Environmental Conservation

EPA-HQ-OAR-2011-

0135-4298

NGVAmerica EPA-HQ-OAR-2011-

0135-4456

Northeast States for Coordinated Air Use 

Management

NESCAUM EPA-HQ-OAR-2011-

0135-4283

Office of County Executive, Anne 

Arundel County, Maryland

EPA-HQ-OAR-2011-

0135-4882

Open Joint-Stock Company EPA-HQ-OAR-2011-

0135-1627

Outdoor Power Equipment Institute OPEI EPA-HQ-OAR-2011-

0135-4457

Ozone Transport Commission OTC EPA-HQ-OAR-2011-

0135-4459

PBF Energy Inc. EPA-HQ-OAR-2011-

0135-4823

PennFuture EPA-HQ-OAR-2011-

0135-4730

Penn Environment (coordinated 

comments)

EPA-HQ-OAR-2011-

0135-4272

Pennsylvania Department of 

Environmental Protection

EPA-HQ-OAR-2011-

0135-4269

Peoples Republic of China EPA-HQ-OAR-2011-

0135-4918
vii

Petroleum Marketers Association of 

America

PMAA EPA-HQ-OAR-2011-

0135-4265

Phillips 66 Company EPA-HQ-OAR-2011-

0135-4463

Philadelphia Physicians for Social 

Responsibility

EPA-HQ-OAR-2011-

0135-4730

Poet, LLC EPA-HQ-OAR-2011-

0135-4462

Refinery Automation Institute, LLC EPA-HQ-OAR-2011-

0135-3471

Renewable Fuels Association RFA EPA-HQ-OAR-2011-

0135-4350

Respiratory Health Association RHA EPA-HQ-OAR-2011-

0135-4731

Revecorp Inc. EPA-HQ-OAR-2011-

0135-4816

Robert Bosch GmbH, Gasoline Systems, 

Germany

EPA-HQ-OAR-2011-

0135-3468

Shell Oil Products for Shell and Motiva EPA-HQ-OAR-2011-

0135-4805

Sierra Club EPA-HQ-OAR-2011-

0135-4311, 4723

Sierra Club (coordinated comments) EPA-HQ-OAR-2011-

0135-0671, 4242

Sierra Club Southeastern Pennsylvania 

Group

EPA-HQ-OAR-2011-

0135-4730

Sierra Club, Clean Air Watch, 

Respiratory Health Association

EPA-HQ-OAR-2011-

0135-4308

Small Business Refiners SBR EPA-HQ-OAR-2011-

0135-4804

Society of Independent Gasoline 

Marketers of America

SIGMA EPA-HQ-OAR-2011-

0135-4327

Southern California Association of 

Governments

SCAG EPA-HQ-OAR-2011-

0135-4352

State of Utah EPA-HQ-OAR-2011-

0135-4879

Sugar House Community Council EPA-HQ-OAR-2011-

0135-4176

Sunoco Logistics Partners L.P. EPA-HQ-OAR-2011-

0135-4290

Sutherland Asbill & Brennan LLP EPA-HQ-OAR-2011-

0135-4884

Textile Industries, Inc. EPA-HQ-OAR-2011-

0135-4731

Thomas Jefferson University Hospital EPA-HQ-OAR-2011-

0135-4730
viii

Truck and Engine Manufacturers 

Association

EMA EPA-HQ-OAR-2011-

0135-4314

Turner, Mason & Company EPA-HQ-OAR-2011-

0135-4757

U.S. Coalition for Advanced Diesel Cars EPA-HQ-OAR-2011-

0135-4759

Union of Concerned Scientists UCS EPA-HQ-OAR-2011-

0135-4317

Union of Concerned Scientists

(coordinated comments)

EPA-HQ-OAR-2011-

0135-1625

United Automobile Workers UAW EPA-HQ-OAR-2011-

0135-2184

United States Congress, House of 

Representatives, Pennsylvania, 7th 

District

EPA-HQ-OAR-2011-

0135-4279

United Steelworkers Union USW EPA-HQ-OAR-2011-

0135-4305

Utah Air Quality Board EPA-HQ-OAR-2011-

0135-4197

Vehicle Services Consulting, Inc. VSCI EPA-HQ-OAR-2011-

0135-4806

VNG.CO EPA-HQ-OAR-2011-

0135-4348

Volkswagen Group of America, Inc. EPA-HQ-OAR-2011-

0135-4299

Volvo Car Group EPA-HQ-OAR-2011-

0135-4296

WE ACT for Environmental Justice EPA-HQ-OAR-2011-

0135-1626

Weaver and Tidwell LLP EPA-HQ-OAR-2011-

0135-4458

Wespath Investment Management EPA-HQ-OAR-2011-

0135-1849

Wyoming Refining EPA-HQ-OAR-2011-

0135-4460

1- Docket Number EPA-HQ-OAR-2011-0135-4731 is testimony from the Chicago, IL public hearing on 

April 29, 2013.

2- Comments from the private citizens coordinated/facilitated by a non-governmental organization.

3- Docket Number EPA-HQ-OAR-2011-0135-4730 is testimony from the Philadelphia, PA public hearing 

on April 24, 2013.
ix

Acronyms and Abbreviations

AAM Alliance of Automobile Manufacturers

ABT Averaging, Banking, and Trading

AECD Auxiliary Emission Control Device

AEO Annual Energy Outlook

A/F air/fuel ratio

AKI Anti-Knock Index ((R+M)/2 octane)

AQCD Air Quality Criteria Document

ARV Accepted Reference Value

ASTM ASTM International (formerly American Society for Testing 

Materials)

bbl Barrel

BC Black Carbon (commonly referred to as “soot”)

BOB Blendstock for Oxygenate Blending

BTU British Thermal Unit

bpcd Barrels per Calendar Day

BTEX Benzene, Toluene, Ethylbenzene, and Xylene

CAA Clean Air Act

CaRFG3 California’s Phase 3 Reformulated Gasoline (Program)

CBOB Conventional Blendstock for Oxygenate Blending

CAFE Corporate Average Fuel Economy

CARB (or ARB) California Air Resources Board

CASAC Clean Air Science Advisory Committee

CBA Cost Benefit Analysis

CBI Confidential Business Information

CCD Combustion Chamber Deposit

CCR California Code of Regulations

CFR Code of Federal Regulations

CG Conventional Gasoline

CMAQ Community Multi-scale Air Quality Model

CNG Compressed Natural Gasoline

CO Carbon Monoxide

CO2 Carbon Dioxide

COA Certificate of Analysis

CR Compression Ratio

CRC Coordinating Research Council

CREE Carbon Related Exhaust Emissions

DALYs Disability Adjusted Life Years

DFE Denatured Fuel Ethanol

DI Direct Injection

DoE, DOE U.S. Department of Energy

DOR Direct Ozone Reduction

DPF Diesel Particulate Filter

DRIA Draft Regulatory Impact Analysis
x

DTC Diagnostic Trouble Codes

E10 Gasoline containing 10 percent ethanol by volume

E15 Gasoline containing 15 percent ethanol by volume

E30 Gasoline-ethanol blend containing 30 percent ethanol by volume

E16-50 Gasoline-ethanol blends containing 16 to 50 percent ethanol by 

volume

E51-83 Gasoline-ethanol blends containing 51-83 percent ethanol by volume

E85 Common name for gasoline-ethanol blends containing 51-83 percent 

ethanol by volume

EFTA European Free Trade Association

EIA Energy Information Administration

EISA Energy Independence and Security Act of 2007

EJ Environmental Justice

EMTS EPA Moderated Trading System

EO Executive Order

EPA Environmental Protection Agency

EPAct Energy Policy Act of 2005

ETBE Ethyl Tertiary Butyl Ether

ETW Emission Test Weight

EU European Union

FCC Fluid Catalytic Cracker

FCEV Fuel Cell Electric Vehicle

FE Fuel Economy

FID Flame Ionization Detector

FID Fuel Injector Deposit

FFV Flex-Fuel Vehicle

FR Federal Register

FRM Final Rulemaking

FTP Federal Test Procedure

FWP Fuel Warming Potential

GDI Gasoline Direct Injection

GHG Greenhouse Gas

GTAB Gasoline Treated as Blendstock

GVWR Gross Vehicle Weight Rating

H6C Harvard Six Cities Study

HAP Hazardous Air Pollutant

HC Hydrocarbon

HDCC High Density Close Coupled

HDGV Heavy-duty Gasoline Vehicle

HDV Heavy-duty Vehicle

HEI Health Effects Institute

HHDGV Heavy Heavy-duty Gasoline Vehicle

HIA Health Impact Assessment

ICE Internal Combustion Engine

ICI Independent Commercial Importer
xi

ILCP Inter-laboratory Cross-check Program

IUVP In-Use Verification Program

IRS Internal Revenue Service

ISA Integrated Science Assessment

ISBL Inside Battery Limits

ISO International Standards Organization

IVD Intake Valve Deposit

LAC Lowest Additive Concentration

LBT Lean Best Torque

LDV Light-duty Vehicle

LDT Light-duty Truck

LEV Low Emission Vehicle

LHDGV Light Heavy-duty Gasoline Vehicle

LML Lowest Measured Level

LNG Liquefied Natural Gas

LPG Liquefied Propane Gas

LVW Loaded Vehicle Weight

MBT Minimum spark advance for Best Torque 

MDPV Medium-duty Passenger Vehicle

mg/kg Milligram per kilogram

MLEB Mid-level Ethanol Blend

MMT Methylcyclopentadienyl Manganese Tricarbonyl

MPG Miles Per Gallon

MSAT EPA’s Mobile Source Air Toxics Rule

MTBE Methyl Tertiary Butyl Ether

MY Model Year

NAAQS National Ambient Air Quality Standard

NATA National Air Toxics Assessment

NGL Natural Gas Liquids

NGO Non-governmental Organization

NHTSA National Highway Transportation Safety Administration

NLEV National Low Emission Vehicle

NMHC Non-methane Hydrocarbon

NMMAPS National Morbidity, Mortality, and Air Pollution Study

NMOG Non-methane Organic Gas

NOx Oxides of Nitrogen; Nitrogen Oxides

Non-VCSB Non-Voluntary consensus-based standards body

NPRM Notice of Proposed Rulemaking

NRC National Research Council

NSR New Source Review

O3 Ozone

O3 AQCD Ozone Air Quality Criteria Document

OBD Onboard Diagnostics

OEM Original Equipment Manufacturer

OMB (White House) Office of Management and Budget
xii

ON Octane Number

OTAQ Office of Transportation and Air Quality

ORVR Onboard Refueling Vapor Recovery

OSBL Outside Battery Limit

PAHs Polycyclic Aromatic Hydrocarbons

PHEV Plug-In Hybrid Electric Vehicle

PBMS Performance-Based Measurement System

P.E. Professional Engineer

PFI Port Fuel Injected

PFID Port Fuel Injector Deposit

PM Particulate Matter

PN Particle Number

POM Polycyclic Organic Matter

Ppm Parts Per Million

PR Precision Ratio

PSI Pounds per Square Inch (pressure)

PTD Product Transfer Document

QALYs Quality-Adjusted Life Years

R&D Research and Development

RBOB Reformulated Blendstock for Oxygenate Blending

RFA Regulatory Flexibility Analysis

RFG Reformulated Gasoline

RFS Renewable Fuel Standard

RIA Regulatory Impact Analysis

RICE Reciprocating Internal Combustion Engine

RIN Renewable Identification Number

RSD Remote Sensing Device

RVP Reid Vapor Pressure

S&A Summary and Analysis of Comments for Control of Air Pollution 

from Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel 

Standards (this document)

SAB Science Advisory Board

SAB-Council SAB Advisory Council on Clean Air Compliance Analysis

SAB-EEAC Environmental Economics Advisory Committee of the SAB

SAE Society of Automotive Engineers

SBA Small Business Administration

SBAR Panel Small Business Advocacy Review Panel

SBREFA Small Business Regulatory Enforcement Fairness Act

SCF Standard Cubic Feet

SCR Selective Catalytic Reduction

SFTP Supplemental Federal Test Procedure

SHED Sealed Housing for Evaporative Determination

SIP State Implementation Plan

SO2 Sulfur Dioxide

SOA Secondary Organic Aerosol
xiii

SRM Standard Reference Material

SVM Small Volume Manufacturer

THC Total Hydrocarbon

TPI Test Performance Index

TTB Tax and Trade Bureau

TZEV True Zero Emission Vehicle

ULSD Ultra-low Sulfur Diesel

UFP Ultrafine Particulates

USC United States Code

VCSB Voluntary Consensus-based Standards Body

VMT Vehicle Miles Traveled

VOC Volatile Organic Compound

VRR Value of a Risk Reduction

VSL Value of Statistical Life

VSLY Value of Statistical Life Year

WOT Wide Open Throttle

WTO World Trade Organization

WTP Willingness to Pay
xiv

Table of Contents

Chapter 1 General

Chapter 2 Authority and Need for the Tier 3 Standards

Chapter 3 Emissions and Air Quality Emissions Impacts

Chapter 4 Tier 3 Vehicle Program

Chapter 5 Tier 3 Gasoline Sulfur Program

Chapter 6 Regulatory Streamlining and Technical Amendments

Chapter 7 Costs

Chapter 8 Estimated Benefits of the Proposed Rule

Chapter 9 Economic Impact Analysis

Chapter 10 Statutory Process

Chapter 11 Comments on Proposed Regulatory Text

Chapter 12 Other
Tier 3 Summary and Analysis of Comments

1-1

1. General

The following comments relate in general to the Notice of Proposed Rulemaking 

(NPRM). The comments in this chapter are not on any specific aspect of the proposed rule; 

rather, they are directed to the general substance of the proposal. More detailed comments on 

specific provisions of the proposal can be found in later chapters of this Summary and Analysis 

of Comments.

For more information on the proposed rule, see the Federal Register at 78 FR 29816, 

published on May 21, 2013. The public comments submitted on this rule can be viewed online 

at www.regulations.gov (the public docket for this rulemaking is docket number EPA-HQOAR-2011-0135).

1.1. General Support for the Proposed Standards

What Commenters Said:

We received many comments supporting the proposed rule, which generally stated that 

they support the rule itself and/or efforts to reduce pollution from motor vehicles and reduce 

sulfur in gasoline. Commenters additionally expressed support for various aspects of the rule, 

including: the systems approach of regulating vehicles and fuel together, harmonization with 

California low emission vehicle (LEV) III standards, coordination with EPA’s light-duty 

Greenhouse Gas (GHG) standards, low sulfur fuels enabling advanced vehicle technologies, 

help for states in meeting National Ambient Air Quality Standards (NAAQS), and finalizing 

the rule by the end of 2013 (in order to retain a January 1, 2017 program start date).

However, many of these commenters also stated that, although they support the rule, 

they believe that additional work should be done before the rule is finalized. Commenters 

offered various suggestions on how they believe that the rule could be improved, and those 

specific comments can be found throughout this Summary and Analysis of Comments 

document.

Our Response:

We appreciate the support we have received from these commenters and many other 

parties during the development of the Tier 3 final rule. The Tier 3 program will establish more 

stringent vehicle emissions standards and will reduce the sulfur content of gasoline beginning 

in 2017, as part of a systems approach to addressing the impacts of motor vehicles and fuels on 

air quality and public health. As described in the preamble to the final rule, we continue to 

believe that the Tier 3 program is necessary, and is technologically and economically feasible 

in the time frame allowed.

For responses to specific issues raised in public comments, please see the separate 

chapters of this Summary and Analysis of Comments document. 
Chapter 1: General

1-2

1.2. General Opposition to the Proposed Standards

What Commenters Said:

We also received comments expressing opposition to the proposed rule. These 

comments listed various concerns such as flawed analyses or processes, and cost/supply 

impacts. These comments are generally summarized below, and are discussed in more detail in 

later chapters of this Summary and Analysis of Comments Document.

Some commenters stated that they believe the rule is unnecessary because EPA failed to 

provide an adequate scientific justification, technical need, or cost effectiveness for the rule. 

These commenters further stated that the rule would impact fuel domestic supplies and affect 

energy security.

Several commenters raised the concern that they believe the rule will result in higher 

costs to the refining and/or vehicle manufacturing industry, and thus raise consumer costs. 

Some of these commenters noted concerns about impacts on jobs in these industries, and a 

number of these commenters further stated that the costs would result in little environmental 

benefit. 

Individual commenters also stated that they do not agree with EPA’s assessments of the 

magnitude to which vehicle emissions cause air pollution, or the health benefits of the rule. We 

also received a number of comments raising concerns that the rulemaking is an example of 

government intrusion.

Commenters:

American Energy Alliance

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

Dresser Trap Rock, Inc.

ExxonMobil

Flint Hills Resources, LP (FHR)

Marathon

Monroe Energy, LLC

Private Citizens

Refinery Automation Institute, LLC

Sunoco Logistics Partners L.P.

United States Congress, House of Representatives, Pennsylvania, 7th District

Our Response:

We have in fact taken the comments we received on the proposal into account and made 

changes to some of the programmatic requirements, where appropriate, which should ease 

implementation (e.g., gasoline sulfur ABT program design) without jeopardizing the benefits of 

the program. We believe that the final rule implements the Tier 3 program in a manner 
Tier 3 Summary and Analysis of Comments

1-3

consistent with our legal obligations, with sound science, and with sound environmental, 

energy, and economic policy.

For responses to specific issues raised in public comments, please see the separate 

chapters of this Summary and Analysis of Comments document. 
Tier 3 Summary and Analysis of Comments

2-1

2. Authority Under the Clean Air Act and Need for the Tier 3 Standards

2.1. Authority

2.1.1. Use of Authority

What Commenters Said:

Commenter: Mercatus Center at George Mason University

Additionally, the EPA regulates both PM and Ozone under the National Ambient Air Quality 

Standards (NAAQS), which makes the proposed regulation an indirect, and perhaps impractical, 

way to achieve the EPA’s objectives.

There are also several unusual aspects to this rule worth mentioning. First, a revision of the 

ozone NAAQS standards was recently returned to the EPA by the Administrator of the Office of 

Information and Regulatory Affairs (13). The EPA was urged to reconsider its ozone proposal 

until after a new review of the scientific literature has been conducted by the Clean Air Science 

Advisory Committee (CASAC). The EPA may want to consider following the same advice for 

this regulation since it is also related to ozone. 

Another unusual aspect of the regulation is that one outcome the agency identifies as a basis for 

regulating is to help states and localities comply with other EPA regulations. The Notice of 

Proposed Rulemaking (NPRM) states, “these reductions would help state and local agencies in 

their effort to attain and maintain health-based National Ambient Air Quality Standards 

(NAAQS)” (14). The EPA should allow states flexibility to achieve standards in ways they think 

are best, rather than mandating how to comply through further regulations. 

It seems odd to use Tier 3 gasoline standards to reduce PM levels when the EPA has the 

authority to reduce PM directly through the NAAQS. 

The EPA has issued this regulation as a result of the authority granted it by the Clean Air Act. 

Given that this regulation is not required by statute, the EPA would be well advised to consider 

holding off on issuing such a regulation until the benefits are more certain.

Our Response:

The commenter states that “the EPA regulates both PM and Ozone under the National 

Ambient Air Quality Standards (NAAQS), which makes the proposed regulation an indirect, and 

perhaps impractical, way to achieve the EPA’s objectives.” The commenter also states that 

EPA’s Tier 3 rulemaking is “a basis for regulating is to help states and localities comply with 

other EPA regulations.” These statements appear to confuse the setting of the NAAQS with 

EPA’s authority to finalize national rulemakings under Clean Air Act Title II. Section 109 (42 

U.S.C. 7409) of the Clean Air Act directs the Administrator to propose and promulgate 

“primary” and “secondary” NAAQS for criteria pollutants (identified under section 108). The 

Act defines primary standards as “ambient air quality standards the attainment and maintenance 
Chapter 2: Authority Under the Clean Air Act and Need for the Tier 3 Standards

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of which in the judgment of the Administrator, based on [air quality] criteria and allowing an 

adequate margin of safety, are requisite to protect the public health.” In setting primary ambient 

air quality standards, the EPA’s responsibility under the law is to establish standards that protect 

public health, without regard to the costs of implementing those new standards. How States 

choose to achieve the NAAQS is not prescribed when the NAAQS is promulgated - the NAAQS 

do not reduce criteria pollutant levels by themselves. 

The Clean Air Act also authorizes EPA to establish emissions standards for motor 

vehicles to address air pollution that may reasonably be anticipated to endanger public health or 

welfare (section 202). EPA also has authority to establish fuel controls to address such air 

pollution as well as fuels emissions products that may impair vehicle emissions controls (section 

211). The EPA’s exercise of these authorities in promulgating the Tier 3 rule does not conflict 

with States’ authority and flexibility in choosing control measures for their plans to attain and 

maintain the NAAQS. Indeed, as noted by the commenter, emission reductions resulting from 

the Tier 3 rule will assist state and local agencies in their efforts to attain and maintain healthbased NAAQS “as expeditiously as practicable” (Section 172(a)2). We received several 

comments from states supporting the Tier 3 program, as described elsewhere in this document. 

The final Tier 3 rulemaking will provide the public with very significant health benefits that are 

achieved at a reasonable cost (refer to Chapter 8 of this Summary and Analysis of Comments

document for specific responses to comments regarding the size and certainty associated with the 

Tier 3 rule’s estimated benefits). 

We also disagree with the commenter’s suggestion that EPA should reconsider its current 

action on the Tier 3 rulemaking based on the delay of most recent ozone NAAQS. This advice is 

irrelevant in the current circumstances due to the very different nature of the two actions – the 

setting of a NAAQS and the promulgation of a national mobile-source air quality rule. The 

overwhelming consensus of the scientific literature finds human exposure to ozone to be 

harmful. The final Tier 3 rule will reduce emissions related to ozone formation and will lead to a 

significant public health benefit.

2.1.2 Authority for Gasoline Sulfur Standards

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

API opposes the requirement to further reduce average gasoline sulfur with this Tier 3 

regulation. This rulemaking is discretionary, and API has serious doubts as to the Agency’s 

justification for it.

Commenter: Monroe Energy, LLC

The Tier 3 sulfur standards are not required by law.
Tier 3 Summary and Analysis of Comments

2-3

Our Response:

Consistent with our proposal, we are adopting gasoline sulfur controls under our 

authority in section 211(c)(1) of the Clean Air Act. This section gives us the authority to 

“control or prohibit the manufacture, introduction into commerce, offering for sale, or sale” of 

any fuel or fuel additive for use in a motor vehicle, motor vehicle engine, or nonroad engine or 

nonroad vehicle (1) whose emission products, in the judgment of the Administrator, cause or 

contribute to air pollution which may reasonably be anticipated to endanger the public health or 

welfare [section 211(c)(1)(A)] or (2) whose emission products will impair to a significant degree 

the performance of any emission control device or system which is in general use, or which the 

Administrator finds has been developed to a point where in a reasonable time it would be in 

general use were the fuel control or prohibition adopted [section 211(c)(1)(B)]. Consistent with 

our proposal, we are finalizing controls on gasoline sulfur levels based on both of the Clean Air 

Act criteria.

We believe that the final rule implements the Tier 3 program in a manner consistent with 

our legal obligations, with sound science, and with sound environmental, energy, and economic 

policy, and we disagree with comments suggesting that the Tier 3 rule is not justified. The Tier 3 

program, including the gasoline sulfur standards, will reduce ambient levels of air pollution that 

endanger public health and welfare and will provide important benefits to the public such as 

preventing PM- and ozone-related premature deaths. The Tier 3 Preamble very clearly explains 

the need for the Tier 3 standards in Section II, our technical justification for the vehicle emission 

controls in Section IV, and technical justification for the fuel standards in Section V. A vast 

body of underlying technical analyses supporting the Tier 3 standards can be found in our 

Regulatory Impacts Analysis, which reflects the best methods, data and assumptions available at 

the time of the rulemaking analysis.

2.1.3 General Support

What Commenters Said:

Commenter: American Lung Association

The Clean Air Act grants EPA the authority to set standards for vehicles and fuels and to reduce 

air pollution that threatens public health under Section 211. The Clean Air Act grants the EPA 

administrator the authority to limit the sulfur and gasoline which reduces the efficiency of 

emission control technologies, and leads to greater tailpipe pollution. When pollution from 

motor vehicles endangers public health, Section 202 of the Act requires the EPA administrator to 

take necessary action.

Commenter: Mid-Atlantic Regional Air Management Association Inc. (MARAMA)

State and local air pollution control agencies have very limited authority to control motor vehicle 

emissions and fuels. Section 177 of the Clean Air Act authorizes states to opt into California's 
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Low Emissions Vehicle tailpipe standards, but Section 211 of the Clean Air Act limits states' 

ability to establish clean gasoline standards. 

Commenter: Sierra Club

Under both provisions, the statutory threshold for determining endangerment is precautionary in 

nature, allowing for regulatory action before the threatened harm occurs.13 “Indeed, the very 

existence of such precautionary legislation would seem to demand that regulatory action precede, 

and, optimally, prevent, the perceived threat.” Moreover, the Administrator’s endangerment 

determination is entitled to great deference, so long as the Administrator provides adequate 

public endangerment justification.15 The statute “allows for a somewhat attenuated chain of 

causation ... Regulation may be premised on a determination that an air pollutant emitted from a 

new automobile is likely to contribute to air pollution which endangers the public health.16 The 

Administrator’s charge of protecting the public from danger, dictates that the Administrator “be 

accorded flexibility, a flexibility that recognizes the special judicial interest in favor of protection 

of the health and welfare of people, even in areas where certainty does not exist.”17 

Upon making its threshold endangerment determination, as EPA has appropriately done here, the 

agency has an explicit duty to promulgate standards under Section 202. The statute provides 

further direction on the stringency of such standards. 

[R]egulations ... applicable to emissions of hydrocarbons, carbon monoxide, oxides of nitrogen, 

and particulate matter from classes or categories of heavy-duty vehicles or engines ... shall 

contain standards which reflect the greatest degree of emission reduction achievable through the 

application of technology which the Administrator determines will be available for the model 

year to which such standards apply, giving appropriate consideration to cost, energy, and safety 

factors associated with the application of such technology. 

And further: The Administrator shall promulgate ... regulations applicable to evaporative 

emissions of hydrocarbons from all gasoline-fueled motor vehicles ... shall take effect as 

expeditiously as possible and shall require the greatest degree of emission reduction achievable 

by means reasonably expected to be available for production during any model year to which the 

regulations apply.

Section 202’s mandatory duty requires EPA to assess “the greatest degree of emission reduction” 

that is “achievable”; that assessment should be informed by the authority conferred to it under 

Section 211 of the Act. Section 211 authorizes the Administrator to “regulat[e], control or 

prohibit” motor vehicle fuels and fuel additives if the subject fuel or fuel additive or any 

emission product from it may contribute to the endangerment of public health or welfare, or if 

the emission products of such fuel or fuel additive will impair to a significant degree the 

performance of any emission control device or system which is in general use or has been 

developed to a point where in a reasonable time it would be in general use if such regulation 

were adopted. As described above, EPA has met its initial threshold consideration by providing 

strong evidence of public health and welfare endangerment.38 EPA also proposes the integrative 

Tier 3 standard based on evidence that gasoline sulfur impairs the emissions control systems of 

vehicles.39 Accordingly, EPA should exercise its authority to regulate pursuant to Section 211, 
Tier 3 Summary and Analysis of Comments

2-5

and should use this authority to inform the stringency of pollution control limits that are 

“achievable” under Section 202. 

EPA Demonstrates that the Proposed Rule is Technologically and Economically Feasible: 

Moreover, in assessing “achievability,” EPA fulfills its obligation to appropriately consider 

technological feasibility, economic feasibility and energy impacts. EPA is entitled to significant 

deference in demonstrating feasibility in light of the complex scientific and technical analysis it 

must undertake. “EPA need only show that technology will be available in the lead time 

provided, not that the technology is currently available.” “EPA will have demonstrated the 

reasonableness of its basis for prediction [that standards are feasible] if it answers any theoretical 

objections ..., identifies the major steps necessary in refinement of the [technology], and offers 

plausible reasons for believing that each of those steps can be completed in the time available.”46

In addition, cost is a consideration but should not be an obstacle for promulgating technology 

forcing regulation.47[EPA-HQ-OAR-2011-0135-4311-A1 p. 9]

In sum, EPA’s record amply demonstrates the pollutant reduction levels and fuel quality controls 

comprising the proposed Tier 3 Rule are technologically and economically feasible. Indeed, EPA 

properly uses its authority to protect public health from motor vehicle air pollution by proposing 

an all-system, integrative Tier 3 standard, and Sierra Club urges EPA to finalize the rule without 

delay. 

Sierra Club applauds the U.S. Environmental Protection Agency for exercising its Clean Air Act 

authority to promulgate the all-system integrative Tier 3 motor vehicle pollution and fuel content 

standards. The proposed Tier 3 standards will achieve significant air pollution reductions that 

will provide very real public health benefits, that cannot be achieved without the Rule’s proposed 

low sulfur gasoline standard. On behalf of Sierra Club’s millions of members and supporters, we 

urge EPA to finalize these standards before December 31, 2013. 

12 42 U.S.C. § 7521(c).

13 Ethyl Corp. v. Envtl. Prot. Agency, 541 F.2d 1. 13 (D.C. Cir. 1976).

15 Train v. Natural Resources Defense Council, Inc., 421 U.S. 60, 75, 95 (1975); Nat’l Petrochemical & 

Refiners Ass’n v. EPA, 287 f.3d 1130 (D.C. Cir. 2002).

16 Ethyl Corp. at 16.

17 Id. (referencing Environmental Defense Fund, Inc. v. Ruckelshaus, 439 F.2d 584, 598 (1971).).

38 Ethyl Corps .v. Envtl. Prot. Agency, 541 F.2d 1, 23-23 (D.C. Cir. 1976) (endangerment threshold must 

be based on assessment of risk and proof of facts).

39 Id. (threshold determination must be factually based). EPA’s research demonstrates significant 

reductions in NOx, CO, and total HC for Tier 2 vehicles as a result of sulfur content 10 ppm and lower. 

EPA makes the case that the proposed standard is an inseparable and indispensable component of 

achieving meaningful air quality benefits. Lowering the sulfur content of fuels both “enable[s] vehicles 

designed to the proposed Tier 3 tailpipe exhaust standards to meet these standards for the duration of their 

useful life, and [] facilitate[s] immediate emission reductions from all the vehicles on the road at the time 

the sulfur controls are implemented.” Control of Air Pollution from Motor Vehicles: Tier 3 Motor Vehicle 

Emission and Fuel Standards. U.S. Environmental Protection Agency, Proposed Rule, RIN 2060-AQ86 

at 67 (Mar. 29, 2013)(hereinafter “Proposed Rule”). Without the proposed sulfur content standards, the 

Tier 3 pollution reductions cannot be achieved. Id.

46 NRDC v. EPA, 655 F.2d 318, 328, 333 (D.C. Cir. 1981); See also Husqvarna v. EPA, 254 R.3d 195, 

201 (EPA not obliged to provide detailed solutions to every engineering problem, but only need to 

identify the major steps for improvement and give plausible reasons for its belief that the industry will be 
Chapter 2: Authority Under the Clean Air Act and Need for the Tier 3 Standards

2-6

able to solve those problems in the time remaining); NRDC v. Thomas, 805 F.2d 410, 429-430 (D.C. Cir. 

1986).

47 Husqvarna AB v. E.P.A., 254 F.3d 195, 201 (D.C. Cir. 2001)(“In construing similar language included 

in CAA section 202, we explained in NRDC v. Thomas that the mere fact that the provisions ‘seek to 

promote technological advances while also accounting for cost does not detract from their categorization 

as technology-forcing standards.’ 805 F.2d at 428 n. 30. The ‘Congress intended the agency to project 

future advances in pollution control capability. It was ‘expected to press for development and application 

of improved technology rather than be limited by that which exists today.’ NRDC v. EPA, 655 F.2d 318, 

328 (D.C.Cir.1981) (quoting S.Rep. No. 91-1196, at 24 (1970)).”

Commenter: Sierra Club

Similarly, Section 211 authorizes the Administrator to regulate and/or prohibit fuels or fuel 

additives if the fuel or fuel additive, or emission product of the fuel causes or contributes to air 

pollution that may reasonably be anticipated to endanger the public health or welfare. The statute 

states:

The Administrator may, on the basis of information ... by regulation, control or prohibit the 

manufacture, introduction into commerce, offering for sale, or sale of any fuel or fuel additive 

for use in a motor vehicle, motor vehicle engine ... if, in the judgment of the Administrator, any 

fuel or fuel additive or any emission product of such fuel or fuel additive causes, or contributes,

to air pollution or water pollution ... that may reasonably be anticipated to endanger the public 

health or welfare, or (B) if emission products of such fuel or fuel additive will impair to a 

significant degree the performance of any emission control device or system which is in general 

use, or which the Administrator finds has been developed to a point where in a reasonable time it 

would be in general use were such regulation to be promulgated.12

12. 42 U.S.C. § 7521(c).

Commenter: Union of Concerned Scientists (UCS)

Additionally, Section 211 of the Clean Air Act allows EPA to establish a fuel standard if 

emissions from fuel combustion cause or contribute to pollution that endangers public health or 

the fuel impairs the performance of the emissions control device or system. EPA is using both 

authorities in promulgating this rule.

Commenter: Sierra Club

EPA Makes an Appropriate Threshold Determination that Motor Vehicle Pollution Endangers 

Public Health

Clean Air Act Sections 202 and 212 Require Regulation Where Pollution Endangers Public 

Health or Welfare

Clean Air Act Sections 202 and 212 provide broad authority to the Environmental Protection 

Agency to regulate motor vehicle pollution and fuel quality to reduce pollution that may 

reasonably be anticipated to endanger public health or welfare. Specifically, Section 202 requires 
Tier 3 Summary and Analysis of Comments

2-7

the Administrator to regulate motor vehicle pollutant emissions upon making a public 

endangerment determination. The statute states: [EPA-HQ-OAR-2011-0135-4311-A1 p. 3]

The Administrator shall by regulation prescribe (and from time to time revise) in accordance 

with the provisions of this section, standards applicable to the emission of any air pollutant from 

any class or classes of new motor vehicles or new motor vehicle engines, which in his judgment 

cause, or contribute to, air pollution which may reasonably be anticipated to endanger public 

health or welfare ...regulations ... shall contain standards which reflect the greatest degree of 

emission reduction achievable through the application of technology which the Administrator 

determines will be available for the model year to which such standards apply, giving 

appropriate consideration to cost, energy, and safety factors associated with the application of 

such technology.11 

11 42 U.S.C. §7521 (a)(1),(3) at 2511–29.

Commenter: Union of Concerned Scientists (UCS)

Section 202 of the Clean Air Act requires that the Administrator of the Environmental Protection 

Agency (EPA) set emission standards from motor vehicles if reductions from vehicles are 

needed and cost-effective. President Obama directed the EPA to promulgate the Tier 3 standards 

at the same time that he asked for the greenhouse gas standards for passenger vehicles in a 

Presidential memorandum released May 21, 2010 (3). [EPA-HQ-OAR-2011-0135-4317-A1, p. 

2]

3 - The White House. 2010. Presidential Memorandum Regarding Fuel Efficiency Standards. Online at 

http://www.whitehouse.gov/the-press-office/presidential-memorandum-regarding-fuel-efficiencystandards accessed on June 28, 2013

Our Response:

We acknowledge the comments and their support of our authority for the Tier 3

rulemaking.

2.2. Need for the Tier 3 Standards

What Commenters Said:

EPA received numerous comments that affirm the need for the emissions reductions, air quality 

improvements, and health benefits that will result from the Tier 3 program. These comments are 

from a broad range of stakeholders, including state and local governments, emissions control 

suppliers, environmental organizations, health organizations, consumer groups, labor groups, 

private citizens, and others. The following list illustrates the breadth and variety of commenters 

that have expressed the need for the Tier 3 standards: 

Advanced Engine Systems Institute (AESI)

American Academy of Pediatrics

American Lung Association

American Lung Association District of Columbia
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American Lung Association Illinois

American Lung Association in Greater Chicago

American Lung Association in Massachusetts et al.

American Lung Association Lehigh Valley, Pennsylvania

American Lung Association Maryland

American Lung Association North Carolina

American Lung Association of the Mid-Atlantic

American Lung Association South Central Pennsylvania

American Lung Association State and Local Chapters

American Lung Association Virginia

American Lung Association, Regional Leadership Council in Northeast Ohio

American Public Health Association

American Thoracic Society

Appalachian Mountain Club

Asthma and Allergy Foundation of America

Attorneys General of New York, Connecticut, Delaware, Maryland, Massachusetts, Maine, 

New Hampshire, North Carolina, Oregon, Rhode Island, Vermont, Washington, 

Washington D.C., New York City, and Chicago

BlueGreen Alliance 

Boulder County Board of Commissioners and Boulder County Board of Health 

Business for Innovative Climate and Energy Policy (BICEP)

Ceres Investor Network on Climate Risk

Chesapeake Bay Foundation 

Chrysler Group LLC

Chicago Metropolitan Agency for Planning

Children's Environmental Health Network

City of Philadelphia Department of Public Health Management Services (AMS)

Clean Air Council

Consumers Union (CU)

Delaware Department of Natural Resources

Emissions Control Technology Association (ECTA)

Environmental Defense Fund 

Environmental Law and Policy Center (ELPC)

HEAL Utah on behalf of members of the Utah Legislature

Health Care without Harm

Kentucky Division for Air Quality 

Maryland Department of the Environment 

Maryland Department of Transportation

Medical Advocates for Healthy Air and Clean Air Carolina 

Metropolitan Washington Air Quality Committee 

Mid-Atlantic Regional Air Management Association (MARAMA)

Mom's Clean Air Force 

National Association of Clean Air Agencies (NACAA)

National Association of City and County Health Officials

Natural Resources Defense Council (NRDC)

Navigant Economics
Tier 3 Summary and Analysis of Comments

2-9

New York State Department of Environmental Conservation (NY DEP)

Northeast States for Coordinated Air Use Management (NESCAUM)

Office of County Executive, Anne Arundel County, Maryland 

Ozone Transport Commission (OTC)

PennFuture 

Pennsylvania Department of Environmental Protection (PA DEP)

Philadelphia Physicians for Social Responsibility 

Private Citizens (over 170,000 comments)

Sierra Club

Sierra Club Southeastern Pennsylvania Group

State of Utah

Sugar House Community Council 

Trust for America’s Health

U.S. Coalition for Advance Diesel Cars

Union of Concerned Scientists (UCS)

United Steelworkers Union (USW)

Utah Air Quality Board

WE ACT for Environmental Justice

Wespath Investment Management

Many comments submitted by the organizations listed above include extensive discussion of why 

the Tier 3 standards are needed both nationally and for the particular locales represented by the 

commenters. In general, commenters made the following points regarding the need for the Tier 

3 standards: 

- Tier 3 will significantly reduce tailpipe emissions of harmful pollutants such as 

particulate matter and gaseous pollution, including nitrogen oxides and volatile organic 

compounds which are ozone precursors. For example:

o In addition to citing EPA’s analyses of emission reductions from the proposed 

Tier 3 standards, many commenters cite a 2011 study by the National Association 

of Clean Air Agencies (NACAA) that estimated the costs and air quality benefits 

of a Tier 3 program modeled on California’s Low Emissions Vehicle (LEV III) 

program, including tighter vehicle emissions standards and an average gasoline 

sulfur standard of 10 ppm. According to the NACAA study, the proposed Tier 3 

standards would to cut emissions of NOx, CO and VOCs by 29%, 38% and 26% 

respectively by 2030. 

- Emission reductions from the Tier 3 gasoline sulfur standards will be immediate for the 

existing fleet. For example:

o Commenters again cite the 2011 NACAA study showing that reducing the sulfur 

content of gasoline would have an immediate effect in 2017, with an expected 

260,000 ton reduction of NOx. The NACAA study estimates that is the equivalent 

of taking 33 million cars off the nation’s roads for a year.

- The Tier 3 standards are needed to improve air quality, both nationally and locally. For 

example:
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o Commenters cited EPA’s proposed Tier 3 analyses and the American Lung 

Association’s State of the Air 2013 report, which found that nearly 132 million 

people, or 42 percent of the nation’s population, live in areas where ozone and 

particulate matter are at levels that are “unhealthful.” 

 Commenters expressed concern for the general public and especially for 

sensitive populations such as children, older adults, those with existing 

conditions such as asthma, reduced lung function, chronic obstructive 

pulmonary disease, heart disease and diabetes.

o Commenters from specific locales often mentioned specific examples of poor air 

quality in their areas, or reported failing grades for various measurements of 

ozone and particle pollution in the air according to ALA’s State of the Air 2013 

report. 

- The Tier 3 standards are critical to helping areas to attain the National Ambient Air 

Quality Standards (NAAQS), as well as assisting areas in staying in attainment. For 

example: 

o Numerous state commenters report on their difficulty in achieving and 

maintaining the current NAAQS and express concerns over meeting potentially 

tighter future standards. They call for national Tier 3 standards to help bring 

needed emission reductions to their states, especially in those areas affected by 

pollutant transport.

o The Ozone Transport Commission (OTC) concluded based on its own modeling 

that “attainment of the 2008 health-based ozone standard will be impossible in the 

OTR without additional emission reductions from highway vehicles and other 

mobile sources.”

o Some commenters point out that their states have already implemented many 

stringent controls, and in the absence of national Tier 3 program, areas needing 

additional emission reductions may have to implement more expensive, less costeffective measures, including additional controls on stationary sources (including 

already controlled sources) to meet their statutory clean air obligations.

 Achieving equivalent emission reductions of the magnitude that will result 

from Tier 3 could be extremely difficult, if not impossible, in areas where 

stationary sources are already highly controlled and there are not enough 

other sources to implement controls.

- Tier 3 will provide substantial health benefits, including preventing instances of 

premature deaths, respiratory related ER visits and hospitalizations, acute respiratory 

symptom days, including asthma attacks, and missed days of work or school. The Tier 3 

standards will also save health care costs. For example:

o Many commenters cited the American Lung Association’s report, “A Penny for 

Prevention: The Case for Cleaner Gasoline and Vehicle Standards,” which 

estimated the full implementation of cleaner gasoline and vehicles in 2030. For 

the eastern half of the United States only, the report projected that Tier 3 would 

prevent more than 2,500 premature deaths each year, avoid more than 15,000 

asthma attacks each year, and avert more than 3.1 million missed work and school 
Tier 3 Summary and Analysis of Comments

2-11

days each year. The monetized health and economic benefits would range 

between $8.5 billion and $22 billion annually. 

o Some commenters also cite a study by Navigant Economics showing that the 

health benefits of the Tier 3 program have an estimated value of $5 to $6 billion 

annually by 2020, and $10 to $11 billion annually by 2030.

- The Tier 3 program is worth the cost. For example: 

o Many commenters make two related points: the Tier 3 program can be achieved at 

a reasonable cost, and the benefits of the Tier 3 program far outweigh the costs. 

Commenters cite analyses such as EPA’s Regulatory Impact Analysis of the Tier 

3 (noting that the costs analyses are corroborated by independent experts), the 

American Lung Association’s report, “A Penny for Prevention: The Case for 

Cleaner Gasoline and Vehicle Standards,” and the Navigant Economics study.

- Tier 3 is important for reducing near-roadway concentrations of vehicle emissions

o Commenters pointed to studies linking roadway-related air pollution with 

increased risks and rates of asthma and other respiratory illnesses, such as the 

2010 report by the Health Effects Institute (HEI), which showed that nearroadway exposure to traffic pollution is high and affects a larger population than 

previously thought.

o Commenters also expressed that traffic-related air pollution and the health 

impacts associated with such pollution raise significant environmental justice 

concerns.

- The Tier 3 standards have important environmental benefits. For example:

o Commenters note that pollutants from motor vehicle emissions (NOx, particulate 

matter, ozone) contribute to the acidification of lakes and streams, the loss of 

native species, poor air quality, and poor visibility. Emission reductions due to the 

Tier 3 standards will reduce damage caused by acid deposition, reduce 

eutrophication, and reduce visibility impairment

o Some commenters cite specific examples of areas where such environmental 

benefits are especially important, e.g., national parks, the Chesapeake Bay.

- Tier 3 provides economic and employment benefits. For example: 

o Some commenters point to the high cost of health care, especially emergency 

room visits and hospital admissions, and applaud the expected cost savings 

projected by EPA’s analyses, the American Lung Association’s report, “A Penny 

for Prevention: The Case for Cleaner Gasoline and Vehicle Standards,” and the 

Navigant Economics study, as illustrated above.

o Some commenters note that Tier 3 will create jobs at refineries and at high-tech 

companies developing and deploying state of the art emission control equipment 

for vehicles, according to the same Navigant Economics study 

o Some commenters also express concerns about the economic burden that would 

be placed on local industries and businesses in areas that cannot meet their 

statutory clean air obligations without the Tier 3 standards 
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2-12

- The Tier 3 rule should be implemented as soon as possible. For example:

o Many commenters expressed their strong desire for the EPA to issue the final Tier 

3 standards by the end of 2013 and implement the standards starting in 2017 as 

proposed, in order to realize the emission reductions, air quality improvements, 

and health benefits of the Tier 3 standards as soon as possible. 

o Some commenters specifically expressed concerns about lost benefits due to any 

delay in the standards.

EPA also received comments from oil industry commenters questioning the need for the Tier 3 

standards. The commenters include:

American Petroleum Institute (API) 

Association of Fuel & Petrochemical Manufacturers (AFPM)

Chevron

Flint Hills Resources, LP (FHR)

Marathon Petroleum Company LP (MPC)

Monroe Energy LLC

Commenters claim that EPA has not demonstrated the need for the Tier 3 gasoline sulfur 

standards and make the following general points. These points are expounded upon in the 

commenter’s detailed comments and thus are also addressed throughout this Summary and 

Analysis of Comments document:

- The environmental benefits of the Tier 3 are negligible with respect to both reductions in 

emissions inventories and improvements in air quality. For example:

o Commenters cite two-API sponsored studies conducted by ENVIRON which 

showed that in 2022, the summertime ozone precursor emissions of volatile 

organic compounds (VOCs), oxides of nitrogen (NOx), and carbon monoxide 

(CO) from gasoline-fueled light-duty vehicles are projected to be reduced by 8%, 

11% and 7%, respectively, due to Tier 3. ENVIRON also found that, in 2022,

Tier 3 would yield a maximum ozone benefit of about less than 1 ppb and mean 

monthly summer 2022 PM2.5 concentrations of no more than 0.1 μg/m3. The 

commenters point out that EPA’s modeling calculates Tier 3 reductions in ozone 

of 0.5 - 1.35 ppb and in PM2.5 of 0 - 0.05 μg/m3in years 2017 - 2030. The 

commenters conclude that reductions of this magnitude are “negligible.”

- The benefits of the Tier 3 program are not worth the cost. For example:

o The commenters claim that EPA’s analyses of the impacts of the Tier 3 as 

described in the Draft Regulatory Impact Analysis are flawed and conclude that 

“the issues below, when taken collectively, demonstrate that the costs of the Tier 

3 proposed rule are greater than the benefits.”

 A flawed baseline 

 Underestimated costs

 Overestimated emissions benefits
Tier 3 Summary and Analysis of Comments

2-13

 Implausible health benefits due to highly conservative, unrealistic 

assumptions

o The commenters further suggest that EPA should withdraw and resubmit a new 

DRIA consistent with OMB guidelines.

- Implementation of the gasoline sulfur standards in 2017 is not necessary. For example:

o Some commenters argue that a January 1, 2017 start date for implementation of 

the gasoline sulfur standards is not necessary to reduce emissions from the in-use 

vehicle fleet. The commenters:

 Question that the Tier 3 standards will have immediate emission 

reductions for the existing vehicle fleet

 Point to the ENVIRON studies of Tier 3 impacts mentioned above to 

argue that the emissions impacts of reducing gasoline sulfur will have only 

a de minimis impact on air quality.

 Further claim that the implementing the rule on January 1, 2017 will not 

help nonattainment areas reach attainment of the NAAQS. 

References:

• American Lung Association (2013). State of the Air 2013. Available at: 

http://www.stateoftheair.org/2013/assets/ala-sota-2013.pdf. 

• American Lung Association (2013). A Penny for Prevention: The Case for Cleaner Gasoline and 

Vehicle Standards. Available at: http://www.lung.org/healthy-air/outdoor/defending-the-cleanair-act/interactive-presentations/cleaner-gasoline-and-vehicles-report-2013.pdf

• ENVIRON International Corporation (2013). Effects of Light-duty Vehicle Emissions Standards 

and Gasoline Sulfur Level on Ambient Ozone. Available at: 

http://www.api.org/~/media/Files/News/2013/13-April/ENVIRON-Sep2012-Effects-of-LDVEmiss-Stds-Gasoline-Sulfur-level-on-Ozone.pdf.

• ENVIRON International Corporation (2013). Effects of Light-duty Vehicle Emissions Standards 

and Gasoline Sulfur Level on Ambient Particulate Matter. Available at: 

http://www.api.org/~/media/Files/Policy/Alternatives/Environ-API-report-vehicle-emissions.pdf.

• Health Effects Institute Panel on the Health Effects of Traffic-Related Air Pollution (2010). 

Traffic-related air pollution: A critical review of the literature on emissions, exposure, and health 

effects. HEI Special Report 17. Available at: http://pubs.healtheffects.org/view.php?id=334

• National Association of Clean Air Agencies (2011). Cleaner Cars, Cleaner Fuel, Cleaner Air: The 

Need for and Benefits of Tier 3 Vehicle and Fuel Regulations. Available at: 

http://www.4cleanair.org/documents/NACAATier3VehandFuelReport-EMBARGOEDOct2011.pdf

• Navigant Economics (2012). Economic Analysis of the Implications of Implementing EPA’s 

Tier 3 Rules. Available at: http://www.ectausa.com/061212-Economic-Analysis-of-theImplications-of-Tier-3-Sulfur-Reduction-Final_embargoed.pdf

Our Response:

We agree with the majority of commenters that there is a significant need for the 

emissions reductions, air quality improvements, and health benefits provided by the Tier 3 

standards, and we disagree with comments from the fuel industry arguing that we have not 
Chapter 2: Authority Under the Clean Air Act and Need for the Tier 3 Standards

2-14

clearly demonstrated that need. As documented in our Regulatory Impacts Analysis (RIA) of the 

Tier 3 rule (Chapters 7 and 8) and described in the Preamble (Sections II, III, and VIII), the Tier 

3 program will significantly reduce motor vehicle emissions, leading to significant air quality 

improvements and helping state and local areas attain and maintain the existing health-based air 

quality standards in a cost-effective and timely way. The breadth and variety of comments we 

received describe the importance of Tier 3’s expected impacts from the perspective of states, 

environmental and health organizations, and the public further demonstrates that the air quality 

improvements and health benefits that will result from the Tier 3 standards are needed. 

With respect to the commenters’ points about the expected emission impacts of the 

standards, we agree with the majority of commenters that Tier 3 standards will significantly 

reduce tailpipe emissions of nitrogen oxides (NOX), Volatile Organic Compounds (VOC), 

particulate matter (PM2.5), and air toxics. For example, our emissions and air quality analyses of 

the final Tier 3 standards (Section III of the Preamble, Chapter 7 of the RIA) show that in 2030, 

NOX and VOC emissions from on-highway vehicles will be reduced by about 330,000 tons and 

170,000 tons, respectively, or about 25% and 16% of emissions from on-highway vehicles. 

These reductions will continue beyond 2030 as more of the fleet turns over; by 2050, when Tier 

3 vehicles would make up almost the entire fleet, NOX and VOC will be reduced by nearly 31% 

for on-highway vehicles. Moreover, immediate reductions are expected in 2017 when the 

gasoline sulfur standards take effect. The gasoline sulfur standards, which take effect in 2017, 

will provide large immediate reductions in NOX emissions from existing gasoline vehicles and 

engines on the road today, e.g., NOX emissions will be reduced by about 260,000 tons, or about 

10% of emissions from on-highway vehicles, in 2018 alone. Given these important emission 

reductions, we disagree with fuels industry commenters that the emission reductions due to Tier 

3 are “negligible.” We respond to more specific comments on our emissions inventory modeling 

and estimated emissions reductions in Chapter 3.1 of this Summary and Analysis of Comments 

document. 

Similarly, we agree with the majority of commenters that the Tier 3 standards will 

significantly improve air quality and that they are critical to helping areas attain and maintain the 

National Ambient Air Quality Standards (NAAQS). As demonstrated in Sections II and III of 

the Preamble, and Chapter 7 of the RIA, the emissions reductions from the Tier 3 standards are 

projected to lead to significant decreases in ambient concentrations of ozone, PM2.5 and air toxics 

(including notable nationwide reductions in benzene concentrations) by 2030, and will 

immediately reduce ozone when the sulfur controls take effect in 2017. Over 149 million people 

currently live in areas designated nonattainment for one or more of the current NAAQS. In the 

absence of additional controls such as Tier 3 standards, many areas will continue to have ambient 

ozone and PM2.5 concentrations exceeding the NAAQS in the future. Our air quality modeling 

indicates this action will meaningfully decrease ozone concentrations in many areas of the 

country. Furthermore, numerous state air quality agencies and organizations representing 

geographic groups of these state agencies have affirmed in their comments that air quality 

improvements from Tier 3 will be a critical part of areas’ strategies to attain and maintain the 

NAAQS. Our analysis of the air quality impacts of the Tier 3 standards clearly shows that these 

improvements are significant, and the need for these improvements is corroborated by the 

majority of comments themselves as well as other studies of Tier 3’s impacts presented in these 

comments. Thus, we disagree with fuel industry comments that the air quality improvements 
Tier 3 Summary and Analysis of Comments

2-15

due to Tier 3 are “negligible,” Our responses to specific claims about our air quality analysis are 

found in Chapter 3.2 of this document. 

We agree with the many commenters who stated that the final Tier 3 rulemaking will provide the 

public with very significant health benefits that are achieved in a cost-effective manner. Our 

analysis of the final rulemaking (Preamble Section VIII and RIA Chapter 8) estimates that by 

2030, the annual emission reductions of the Tier 3 vehicle and fuel standards will annually 

prevent between 660 and 1,500 PM-related premature deaths, between 110 and 500 ozonerelated premature deaths, 2,200 hospital admissions and asthma-related emergency room visits, 

19,000 asthma exacerbations, 30,000 upper and lower respiratory symptoms in children, and 1.3 

million lost school days, work days, and minor restricted activity days. Given the expected 

health benefits stemming from air quality improvements due to Tier 3’s expected emissions 

reductions, we again conclude that Tier 3’s emission and air quality impacts are not “negligible” 

as the fuel industry commenters claim. The estimated annual monetized health benefits of the 

Tier 3 standards in 2030 (2011$) will be between $7.4 and $19 billion, assuming a 3-percent 

discount rate (or between $6.7 billion and $18 billion assuming a 7-percent discount rate). We 

project the final fuel standards to cost on average 0.65 cent (i.e., less than a penny) per gallon of 

gasoline, and the final vehicle standards to have an average cost that increases in proportion to 

the increase in stringency during the phase-in period, from $28 per vehicle in 2017 to $72 per 

vehicle in 2025, when the standards are fully phased in (our cost analyses can be found in 

Preamble Section VII and RIA Chapters 2, 5 and 8). Costs in 2030 are estimated to be 

approximately $1.5 billion. Using the more conservative benefits estimate, the 2030 benefits 

outweigh the costs by a factor of 4.5. Using the upper end of the benefits range, the benefits 

outweigh the costs by a factor of 13. Thus, even taking the most conservative benefits 

assumptions, benefits of the final standards clearly outweigh the costs. 

We therefore disagree with comments suggesting that the benefits of the Tier 3 program 

are not worth the cost. We further disagree with each of the fuel industry commenters’ specific 

points that our baseline is flawed, that we underestimate costs and overestimate benefits, and that 

estimated health benefits are implausible due to unrealistic assumptions. Our methods have been 

thoroughly peer reviewed and reflect the best methods, data and assumptions available at the 

time of the rulemaking analysis. Furthermore, these methods are consistent with OMB and 

internal EPA guidelines for analyzing the impacts of a national-level rulemaking, and we reject 

the claim made by fuel industry commenters that EPA should withdraw and resubmit a new 

Regulatory Impacts Analysis. Chapters 3, 4, 5, 7, 8 and 10 of this document contain more

detailed responses to the commenters’ specific claims. 

With respect to comments on other impacts of the Tier 3 standards, we agree with the 

many commenters who stated that Tier 3 is important for reducing near-roadway concentrations 

of vehicle emissions and that Tier 3 has significant environmental benefits. Tier 3 will reduce 

exposure to vehicle pollution for the millions of people living, working, and going to school near 

major roads, and thus delivering significant emissions benefits to communities across the U.S. 

beginning in 2017 when the gasoline sulfur standards take effect. The reduction in air pollutants 

resulting from the Tier 3 program will also have environmental, or “welfare,” co-benefits in 

addition to human health benefits, including changes in visibility, materials damage, ecological 

effects from PM deposition, ecological effects from nitrogen and sulfur emissions, vegetation 
Chapter 2: Authority Under the Clean Air Act and Need for the Tier 3 Standards

2-16

effects from ozone exposure, and climate effects. For example, our analysis shows that the Tier 

3 standards will provide improvements in visibility and sulfur deposition, as well as substantial 

decreases in nitrogen deposition as a result of the standards (Preamble Section III and RIA 

Chapter 7). We note that despite our goal to quantify and monetize as many of the benefits as 

possible for the final rulemaking, the welfare co-benefits of the Tier 3 standards remain 

unquantified and non-monetized in this RIA due to data, methodology, and resource limitations. 

As a result, the benefits quantified in this analysis are likely underestimates of the total benefits 

attributable to the final program. 

While some commenters point to employment as another benefit of the Tier 3 standards, 

as discussed in Preamble Section X.D and RIA Chapters 9.2.2 and 9.3.2, EPA expects the 

employment effects of these standards to be small. Some commenters argue that the standards 

may increase, rather than decrease, employment (see Chapter 9.3 of this Summary and Analysis 

of Comments document); EPA does not quantify most of the employment impacts of the 

standards and thus does not evaluate these estimates.

Given the important emissions reductions, air quality improvements, and health benefits 

that Tier 3 will deliver, we agree with the majority of commenters that the Tier 3 standards 

should be implemented as soon as possible. We are finalizing a Tier 3 program that, as 

proposed, begins with model year 2017 for vehicle emission controls and with calendar year 

2017 for the gasoline sulfur standards. As described briefly above and in Section III of the 

Preamble and Chapter 7 of the RIA, the Tier 3 standards will provide immediate and meaningful 

emission reductions and air quality improvements starting in 2017 due to the sulfur standards. 

We reject the fuel industry commenters’ claims to the contrary, and address their specific points 

(e.g., that 2017 implementation will not help ozone NAAQS attainment) in Chapters 3 and 5 of 

this document. 
Tier 3 Summary and Analysis of Comments

3-1

3. Emissions and Air Quality Emissions Impacts

The comments in this chapter correspond to Section III of the preamble to the proposed 

rule and address the emissions and air quality impacts of the program. The comments received 

and our responses to those comments are located below.

3.1 Emission Impacts of the Proposed Program

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon

Overestimated emissions benefits. We recommend that EPA uses EIA’s AEO 2013 as the 

baseline to account for declining gasoline demand. EPA relied on EIA’s Annual Energy Outlook 

in 2011 (AEO 2011), which projected 4% higher gasoline demand in 2030 vs. 2012.

The analysis in Figure 10 [EPA-HQ-OAR-2011-0135-4276-A2] compares gasoline demand and 

vehicle miles travelled in AEO 2011 with AEO 2013. Using as baseline AEO 2013 instead of 

AEO 2011, in 2030 gasoline demand is projected to be 26% lower, vehicle miles travelled 11% 

lower, and gasoline consumption in gallons per mile 16% lower.

In line with this analysis, baseline emissions are expected to be lower than EPA’s assumed 

baseline. As a result, the emissions benefits from Tier 3 are overstated. 

Our Response:

For purposes of this final rule, we estimated emissions reductions compared to a 

reference case that assumed renewable fuel volumes and ethanol blends based on the U.S. 

Energy Information Administration’s Annual Energy Outlook 2013 (AEO2013). Furthermore, 

the future year projections of vehicle population and vehicle miles travelled were updated to 

reflect the latest estimates from AEO2013 as well. Additional details can be found in Section III 

of the preamble for the final rule.

3.1.1. Emissions Inventory Modeling Methodology

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

EPA should correct a number of deficiencies in the methods incorporated into the MOVES 

model which lead to an overstatement of the emissions inventory benefits of Tier 3.

A recent assessment of the version of MOVES used by EPA to estimate the emissions benefits of 

the Tier 3 proposal identified several key issues with this model, including the following: 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-2

The FTP driving cycle used by EPA in its sulfur test program to develop fuel sulfur correction 

factors to implement in the MOVES model for adjusting the exhaust emissions of Tier 2 and 

newer light-duty vehicles is a mild cycle that does not cover the full range of accelerations in-use 

and does not include high-speed operation. In fact, the FTP test represents only a small fraction 

of the running exhaust emissions, particularly for Tier 2 vehicles. Consequently, the fuel sulfur 

impacts for running exhaust emissions which EPA developed based on the FTP cycle are not 

representative of the vehicle operating modes that produce the bulk of the exhaust emissions, and 

this renders the adjustments for 2004 and later model years in the version of MOVES used for 

the NPRM highly questionable. 

The 2003 and older model year methods also rely on FTP-based measurements and the

concerns about the representativeness of the FTP cycle for sulfur effects modeling are already

described above. 

Our Response:

The FTP driving cycle used in the in-use sulfur program was chosen to represent the type 

of driving that manufacturers must cover in their certification testing to evaluate the in-use 

emissions performance. The commenter raises a valid argument that the contributions of 

emissions are expected to vary by vehicle operating modes and that the effect of sulfur on 

exhaust emissions for the high-speed operations, not covered by FTP cycle, may not perform 

similarly to the FTP cycle. However, the commenter failed to acknowledge that the CRC E-60 

study cited by the commenter suggests that the magnitude of the fuel sulfur effects over the 

US06 cycle for NMHC and NOx was found to be larger than that found for the FTP cycle. In 

fact, the effects of sulfur going from 30 ppm to 5 ppm observed in the study on US06 cycle 

(statistically significant reduction of 40% and 44% for NMHC and NOx, respectively) are larger 

than the effects on FTP composite observed from the in-use sulfur study (statistically significant 

reduction of 11% and 23% for NMHC and NOx, respectively). When using predictive models to 

support rules, EPA has to make judgments regarding what modeling information is available and 

whether the information is of adequate quality to support the conclusion being reached. Thus, in 

this instance, although it may be difficult to compare the results from two different test programs 

due to methodological differences, the finding does suggest that the application of the results 

from FTP cycle to broader ranges of vehicle operation is a reasonable approach for modeling the 

effects of sulfur on Tier 2 and newer vehicles.

What Commenters Said:

The review described here focused on the integration of the EPAct data into the NPRM MOVES

model. The EPAct-based equations form the basis for all

2004 and newer model year exhaust corrections (for both Tier 2 and Tier 3 certified vehicles). 

Two items addressed in this discussion are (1) inconsistencies in equation coefficients between 

EPA references and (2) the representativeness of the EPAct Program test fleet. 
Tier 3 Summary and Analysis of Comments

3-3

There are numerous inconsistencies between the EPA evaluation of the EPAct test data as 

documented in EPA-420-R-13-002 and the methods incorporated into MOVES for estimating 

non-sulfur fuel effects for 2004-and-later model years. It is unclear if errors were made in 

reporting or in the incorporation of methods into MOVES. 

The first discrepancy found was that the EPAct analysis report developed equations for two 

forms of reduced models, as described in Section 5 of this report: the 11-term reduced models 

and the 16-term reduced models. The report goes into detail as to why the 11-term reduced 

models are statistically preferable, and the 11-term reduced models are the only form of the

equations provided in the Executive Summary of the report. This becomes a discrepancy

because it is the 16-term reduced models that were programmed into NPRM MOVES for all 

pollutants and process combinations except one (NOx start exhaust equations in NPRM MOVES

are based on the 11-term reduced model). EPA needs to provide the technical justification for

the selection of the NPRM MOVES model equations and why those differ from the

recommendations of the EPAct Program analysis report. 

Our Response:

The coefficients used in the NPRM application of MOVES, and reported in the docket 

memorandum1, reflect the state of analysis at the time it needed to be completed for the NPRM. 

However, following the initiation of inventory generation and air-quality modeling supporting 

the NPRM, analysis of the EPAct dataset continued through October, 2012. The sets of 

coefficients used in the FRM application of MOVES reflect the subsequent developments and 

analysis described in the final report.

2

The sets of coefficients used in the NPRM could be 

considered as “draft” versions, and those used in the FRM as “updated” or final versions based 

on the analyses described in the final report.

What Commenters Said:

The second discrepancy is that the THC running exhaust equation coefficients shown in Table 6-

6 do not appear anywhere in the EPA Program analysis report. These THC equation coefficients 

used by NPRM MOVES are undocumented. It is presumed that these are some variation of the

16-term reduced model of the EPAct Program analysis report based on which parameters have a

non-zero coefficient. 

Our Response:

These coefficients are documented in the docket memorandum as are the other 

coefficients1. The commenter correctly notes that this set of coefficients is a version of the 16-

term model. However, they can be considered a “draft” version, reflecting model fitting using all 

15 vehicles. Those in the final report reflect additional quality assurance, as described in 

 

1 U.S. EPA, 2013. “Memorandum to Docket: Updates to MOVES for the Tier 3 NPRM”

2 U.S. EPA, 2013. Assessing the Effect of Five Gasoline Properties on Exhaust Emissions from Light-Duty Vehicles 

Certified to Tier-2 Standards: Analysis of Data from EPAct Phase 3 (EPAct/V2/E-89). Final Report. EPA-420-R13-002. Assessment and Standards Division, Office of Transportation and Air Quality. Ann Arbor, MI.
Chapter 3: Emissions and Air Quality Emissions Impacts

3-4

Chapter 6 of the Report. As a result, two vehicles were dropped before final model fitting, 

leading to small changes in the coefficients. However, the qualitative relationships among the 

terms in both the draft and final models are similar.

In addition, the coefficients used in the NPRM are documented in the final report in Appendix E 

“Preliminary Reduced Models,” as noted in 5.4 (page 100).2 These preliminary models were 

used to identify influential vehicles, as described in 5.5. 

What Commenters Said:

The third discrepancy is that three instances were found in which coefficients were inconsistently

assigned to a given fuel parameter. These are shown in Table 6-7. It is not clear if the EPAct 

reporting is in error or if the MOVES modeling equations are in error. 

Our Response:

The commenter has correctly noted an editorial error in the report. 

In the report tables for the 16-term models, the effects are not listed in the correct order, 

as in the Appendices. For THC Start emissions, the commenter has noted an editorial error in 

Table 57. In this table, the labels for the model terms etOHxT50, etOHxT90 are not listed in the 

correct order, leading to incorrect associations of coefficients with model terms. The correct 

order should be etOHxRVP, etOHxT50, etOHxT90.

The same editorial error applies to the CO start term listed in Table 6-7 above. In report 

table 65, it is incorrectly associated with the etOHxT90 effect, rather than the etOHxT50 effect.

However, in both these cases, the editorial errors are not germane to the FRM application 

of the model, as the terms used in MOVES for the FRM analysis are those for the 11-term 

models listed in the previous tables (Table 56 for THC, Table 64 for CO). The terms are listed 

in correct order in these report tables.

What Commenters Said:

The fourth discrepancy, albeit a minor one, was that there were a number of instances where the

equation coefficients differed between NPRM MOVES and the EPAct Program analysis report 

and the difference was not due to round off error.

79 For example, the CO running exhaust T50

term is 0.024856 in NPRM MOVES and 0.02484 in the EPAct Program analysis report. 

Our Response:

The commenter correctly lists the term used in the NPRM model, as well as that from the 

16-term CO model, listed in Table 65. Again, the small difference highlighted is not germane to 
Tier 3 Summary and Analysis of Comments

3-5

the model applied in the FRM, which is that listed in Table 64. In this model, the T50 term is 

0.0261, slightly larger than that in the 16-term model. However, numeric values of coefficients 

nearly always have differences between models fit starting with 11 vs. 16 terms. This outcome is 

routine and expected.

What Commenters Said:

The second issue concerns the representativeness of the EPAct Program test fleet, which was 

also discussed in Section 5 [EPA-HQ-OAR-2011-0135-4276-A13].

Our Response:

The comment is premised on an assumption that fuel effects would or should differ 

between vehicles or groups of vehicles with differing emission levels, whether due to technology 

or to age. In fact, evidence suggests that fuel effects among vehicles with different emissions 

levels will differ in absolute terms (i.e., g/mi) but tend to be similar in relative terms (i.e., ratios, 

percents). That is to say, fuel effects (as well as other effects) are multiplicative rather than 

additive.

One example that illustrates the point is available in the EPAct dataset itself. The first 

plot (Figure 3-1) shows the data for cold-start NOx, averaged by aromatics level and by vehicle. 

If we look at the trend for the Altima, we can see that its NOx increases from about 0.13 to 0.178 

g/mi as aromatics increases from 15% to 35%, giving an absolute difference of nearly 0.05 g/mi. 

In contrast, the corresponding increase for the cleanest vehicle, the Sienna, is about 0.002 g/mi 

(0.0081 – 0.0059 g/mi). Thus, start emissions for the Altima are 21-22 times higher than those 

for the Sienna at both aromatics levels.

The second plot (Figure 3-2) shows the same data plotted on a natural-log scale. What 

immediately strikes the viewer is the similarity in logarithmic trends for all the vehicles across 

the entire range of emissions, allowing for statistical variability. Again focusing on the Altima 

and Sienna, examination shows that the slopes of the trends are nearly identical for these two 

vehicles; that is to say, the logarithmic differences are extremely close. As differences in 

logarithms can be interpreted as ratios, the implication is that the effect of aromatics for these 

two vehicles, expressed as a ratio, i.e., multiplicatively, is nearly identical. Examination of plots 

for the various emissions, as shown in the body of the report, as well as in the Appendices, 

shows that this pattern is typical of emissions behavior in relation to changing fuel effects.

As the models developed from these data are fitted to logarithmic transforms of the 

emission results, the various coefficients can be viewed as representing multiplicative effects of 

the changing fuel properties. Similarly, the models are applied in MOVES so as to generate 

multiplicative effects. On this basis, we find it reasonable to apply the multiplicative effects 

across groups of vehicles of differing standards and different ages, with the realization that 

projected differences in emissions related to changes in fuel properties will be proportional to the 

projected emission levels. As previously explained, EPA has to make judgments regarding what 

modeling information is available and whether the information is of adequate quality to support 

the conclusion being reached. Thus, based on available evidence, it is reasonable to assume that 

the fact that the EPAct sample comprised relatively young and clean (Tier 2) vehicles does not 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-6

impair the applicability of the models to the Tier 2 fleet as these vehicles age and acquire 

mileage.

Figure 3-1 Linear effects plot for cold-start NOx vs. aromatics, with data averaged by two aromatics levels and by 

vehicle (Source: EPAct Phase 3)
Tier 3 Summary and Analysis of Comments

3-7

Figure 3-2 Linear effects plot for cold-start ln(NOx) vs. aromatics, with data averaged by two aromatics levels 

and by vehicle (Source: EPAct Phase 3)

What Commenters Said:

The extrapolation of Tier 0 Non-sulfur fuel effects to Tier 1 through NLEV technologies has not 

been properly validated. 

Our Response:

The commenter is correct that the Complex and Predictive models were developed using 

data from Tier 0 vehicles and that the resulting models are applied to Tier 1 vehicles in MOVES. 

Similarly, it is correct that the EPAct models were developed using a set of low-mileage Tier 2 

vehicles, and that in MOVES, the models are applied to Tier 2 vehicles as they age and acquire 

mileage. Nonetheless, we argue that these extrapolations are reasonable and appropriate given 

the ways in which the models were developed and the fuel adjustments applied.

The comment is premised on an assumption that fuel effects should differ in some way 

between vehicles of differing technologies ages or “high-emitter” status. As mentioned above, 

fuel effects are represented in MOVES as multiplicative effects that are proportional to base 

emission levels. We agree with the commenter that when fuel effects are expressed as absolute 

changes in mass (e.g., g, g/mi, g/kg, etc.), vehicles of different technologies or ages will differ 

strongly. We do, however, assume that proportional, or relative fuel effects (expressed as 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-8

fractions, ratios or logarithmic differences), can be seen as similar, and thus transferrable on 

average across technology groups and ages. 

The data available to directly evaluate this assumption are limited. Nonetheless, a 

limited volume of data can be compiled from the results of the EPAct program, as described 

below. 

The models applied in MOVES were developed from the results of EPAct Phase 3, in 

which 15 Tier 2 vehicles were measured on 27 fuels. In addition, in EPAct Phase 5, three 

vehicles manufactured in the 1990’s were measured on three fuels used in Phase 3. Thus, using 

these results, it is possible to make a direct comparison of emissions for sets of pre-Tier 2 and 

Tier 2 vehicles measured on the same fuels (at 75°F). 

The three 1990’s vehicles are briefly described in Table 3-1. Note that these vehicles 

range from 10-17 years in age and that all had presumably accumulated over 150,000 mi.

In terms of fuels, we limited the comparison to 2 fuels with 0% and 10% ethanol content, 

respectively. These two fuels are closely matched in terms of RVP and aromatics levels, and 

differ slightly in T50. However, they differ widely in T90, which is not expected to strongly 

affect NOx emissions, but is expected to influence HC, CO and PM emissions. The properties of 

these fuels are summarized in Table 3-2. Note that emissions on both fuels were acquired for 

only two of the three vehicles.

Table 3-1 Characteristics of three “high-mileage” pre-Tier 2 vehicles measured in EPAct Phase 5

Make/Model Engine Model Year Odometer (mi)

Chevrolet Tahoe V8 – 5.7 L 1997 221,000

Ford Taurus V6 – 3.0 L 1990 X90,4003

Dodge Dakota 1993 229,000

Table 3-2 Selected properties of two fuels measured in EPAct (Phase 5)

Fuel No. Ethanol (vol. %) Aromatics (vol. %) RVP (psi) T50 (°F) T90 (°F)

6 10.56 15.0 7.24 188.5 340.4

7 <0.10 17.0 7.15 193.1 298.4

At the outset, we averaged the results by vehicle and fuel, and plotted the results for both 

cold-start and hot-running phases of the LA92 cycle. Results for NOx, THC and PM are shown 

 

3 The odometer for this vehicle is assumed to have been rolled over.
Tier 3 Summary and Analysis of Comments

3-9

below in Figures Figure 3-3Figure 3-5. Note that the results are shown on a logarithmic scale 

(base 10). This view of the data facilitates showing the results for all the vehicles in one plot. In 

addition, differences in logarithms can be interpreted as proportional or relative differences 

between the fuels for the various vehicles.

Aside from the fact that their emissions are higher, the differences in logarithms between 

the two fuels are not obvious for the older “high-mileage” vehicles. Although the sample of 

older vehicles is small, a qualitative view of the plots suggests that no clear and obvious 

differences between Tier 0, Tier 1 and Tier 2 vehicles are evident.

It is helpful to follow up with a closer examination of this subset of results. As 

mentioned, differences in logarithms represent ratios, e.g., log a – log b = log(a/b). However, for 

purposes of summary, it is more intuitive to express the results as percent differences between 

fuels 6 and 7 (relative to fuel 7). Accordingly, mean percent differences for the set of vehicles 

are presented below in Figure 3-3 through Figure 3-5 for NOx, THC and PM, respectively. In 

each plot, the differences are ranked from smallest to largest, meaning that the ordering of the 

vehicles differs in each chart. 

In reviewing the charts, it is clear that when the differences in emissions between the two 

fuels are viewed as fractions, there are no clear or obvious differences between the 1990’s 

vintage high-mileage vehicles and the MY 2008 Tier 2 compliant low-mileage vehicles. 

Generally, the two high-mileage vehicles differ in the signs of their effects, with one vehicle 

showing a positive and the other a negative change. Cold-start PM is the only case in which 

both vehicles have negative effects and have low rankings. Hot-running THC also stands out as 

the only case in which the two older vehicles have the largest and smallest fractional effects. In 

the remaining cases the older vehicles are distributed evenly across the rank order.

Overall, the available evidence suggests that when fuel effects are expressed as relative 

multiplicative factors, as they are in both the EPAct analyses, and in their applications in 

MOVES, it is reasonable to assume that the proportional effects are transferrable across different 

vehicle technologies, as well as across other factors such as age, mileage or “high-emitter” 

status. Furthermore, “That a model is limited or imperfect is not, in itself a reason to remand 

agency decisions based upon it.” Appalachian Power Company v. EPA, 251 F.3d 1026, 1051 

(D.C. Cir. 2001)(internal citations omitted). “It is only when the model bears no rational 

relationship to the characteristics of the data to which it is applied that [courts] will hold that the 

use of the model is arbitrary and capricious.” Appalachian Power Company v. EPA, 135 F.3d 

791, 802 (D.C. Cir. 1998)(internal citations omitted). 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-10

Figure 3-3 Mean percent difference in NOx cold-Start (top) and hot-running (bottom) emissions from 

14 Tier 2 and 2 pre-Tier 2 vehicles measured on two fuels

-100 -5 0 0 5 0 100 150 200

ODYSSEY

LIBERTY

COROLLACE

COBALT

Tahoe(97)

F150

IMPALALS

CALIBER

SILVERADO

EXPLORERXLT

ALTIMA

CAMRY

Taurus(90)

OUTLOOKXE

SIENNA

CIVIC

Mean Difference (%)

-100 -5 0 0 5 0 100 150 200

CALIBER

EXPLORERXLT

OUTLOOKXE

LIBERTY

IMPALALS

Tahoe(97)

ALTIMA

CAMRY

F150

SIENNA

SILVERADO

Taurus(90)

ODYSSEY

COROLLACE

FOCUS

CIVIC

Mean Difference (%)
Tier 3 Summary and Analysis of Comments

3-11
Chapter 3: Emissions and Air Quality Emissions Impacts

3-12

Figure 3-4 Mean percent difference in THC cold-start (top) and hot-running (bottom) emissions from 

14 Tier 2 and 2 pre-Tier 2 vehicles measured on two fuels

-5 0 0 5 0 100 150

COROLLACE

F150

CIVIC

SILVERADO

OUTLOOKXE

EXPLORERXLT

SIENNA

CALIBER

Taurus(90)

IMPALALS

COBALT

ODYSSEY

FOCUS

Tahoe(97)

LIBERTY

CAMRY

ALTIMA

Mean Difference (%)

-5 0 0 5 0 100 150

Taurus(90)

ALTIMA

CALIBER

EXPLORERXLT

COBALT

SILVERADO

IMPALALS

COROLLACE

OUTLOOKXE

F150

CAMRY

LIBERTY

CIVIC

FOCUS

Tahoe(97)

Mean Difference (%)
Tier 3 Summary and Analysis of Comments

3-13
Chapter 3: Emissions and Air Quality Emissions Impacts

3-14

Figure 3-5 Mean percent difference in PM cold-start (top) and hot-running (bottom) emissions from 

14 Tier 2 and 2 pre-Tier 2 vehicles measured on two fuels

-200 -100 0 100 200 300 400 500

CAMRY

COROLLACE

Taurus(90)

SIENNA

Tahoe(97)

SILVERADO

IMPALALS

FOCUS

EXPLORERXLT

LIBERTY

F150

CIVIC

ODYSSEY

ALTIMA

CALIBER

OUTLOOKXE

COBALT

Mean Difference (%)

-200 -100 0 100 200 300 400 500

COROLLACE

CALIBER

ALTIMA

OUTLOOKXE

Taurus(90)

CAMRY

CIVIC

SIENNA

IMPALALS

EXPLORERXLT

ODYSSEY

F150

SILVERADO

Tahoe(97)

LIBERTY

Mean Difference (%)
Tier 3 Summary and Analysis of Comments

3-15

What Commenters Said:

Tier 0 exhaust impact equations, for modeling fuel effects, are extrapolated to E15, which is not 

supported by data. 

The model does not restrict E15 usage to the fleet legally allowed to use the fuel (2001-and-later 

model year light-duty vehicles). Rather all gasoline vehicles were modeled as operating on E15 

at a uniform market share.

Our Response:

The MOVES model is not currently capable of partitioning a fuel supply market share 

differently based on vehicle model year. This indeed leads to modeling pre-2001 vehicles with 

an E10/E15 fuel supply, using the Complex model to apply fuel effects on these vehicles. We do 

not mean to imply that pre-2001 vehicles would be fueling with E15 in the future; this outcome 

is rather an artifact of how fuel supplies are partitioned inherently in the MOVES model. In the 

interest of completeness, we performed further analysis using a fuel supply that does not contain 

E15. As shown in Figure 3-6, the application of adjustments based on the Complex model results 

in only minor fuel effect differences between E10 and E15, as this model is not as sensitive to 

ethanol level as the fuel effects model used in later model years (based on EPAct Program). We 

do not believe that this difference contributes significantly to the overall emissions inventories 

used in the Tier 3 modeling.
Chapter 3: Emissions and Air Quality Emissions Impacts

3-16

Figure 3-6 NOx start emissions based on the Complex model for mix of E10/E15 and E10 only

What Commenters Said:

The NPRM MOVES has two severe flaws in the manner by which RVP impacts are modeled: 

(1) predictive equations are extrapolated far outside the range of RVP measured in the underlying

test data; and (2) temperature interactions with RVP are not addressed. 

RVP impacts on exhaust have critical flaws, primarily in winter season modeling, due to 

excessive RVP extrapolation and a failure to evaluate temperature interactions.

Our Response:

The commenter is correct in pointing out that the fuel effects applied in the MOVES 

modeling do extrapolate beyond the RVP range spanned by the data underlying the models used 

to estimate fuel-effect adjustments i.e., 7-10 psi. 

Despite the implication that this approach would result in large errors, we believe that it is 

reasonable to assume that the relationships between log(Emissions) and RVP can be extrapolated 

linearly from the range from 7-13 psi. This extrapolation, while not necessarily exact, can be 

presumed to yield reasonable approximations over both summer and winter RVP ranges. 
Tier 3 Summary and Analysis of Comments

3-17

Evidence supporting this assumption is available from the same study cited by the commenter, 

namely, CRC E-74b. 

This study measured emissions of the three gaseous pollutants on 15 vehicles (MY 1994-

2004), spanning various vehicle technologies and emission standards. Measurements were 

conducted on the FTP cycle at two temperatures (50 and 75 °F). Selection of study fuels 

attempted to focus on varying ethanol and RVP while maintaining other important properties 

constant (e.g., aromatics, T50 and T90), with the goal of assessing interactions between 

temperature and RVP effects over the temperature range applicable to the southwestern U.S. 

We performed a simple re-analysis of the study results, focusing on a subset of the data 

allowing assessment of the linearity of relationships between log-transformed emissions and 

RVP. We thus examined results for a subset of five fuels spanning ethanol levels on the range 

from 0-10 vol. %, and RVP on a range from 7-13 psi. This subset was also restricted to a 

temperature of 75 °F, as the fuels with 7 psi RVP were not measured at the lower temperature. In 

addition, we examined results for Bags 1 and 2 of the FTP, as the calculations in MOVES handle 

start and running emissions separately.

Emissions vs. RVP are presented on logarithmic scales for Cold-start and Hot-running 

FTP emissions in Figures Figure 3-7Figure 3-9 below. In this presentation, the data are averaged 

by RVP and vehicle. For each vehicle, a linear trend line is shown. An overview of the results 

suggests that while some uncertainty exists as to whether some of the trends with RVP have a 

small degree of curvature, linear extrapolation over the measured range can be expected to give 

reasonable results.

The graphic results were followed up with statistical modeling. We modeling the naturallog transform of the emissions versus ethanol, RVP, a quadratic term for RVP (to test for 

curvature) and an ethanol RVP interaction. For modeling purposes, the fuel properties were 

standardized to neutralize collinearity between the 1st and 2nd order terms. “Mixed modeling” 

techniques were used with random intercepts fit for each vehicle to isolate the effects of fuel 

properties from the substantial variability contributed by the vehicles. 

The results are briefly summarized in Table 3-3 below. A statistically significant 

RVP×RVP interaction was evident only for CO Cold-start emissions (Bag 1), suggesting some 

degree of curvature in the relationship over the range of 7-13 psi. In addition, significant linear 

trends for RVP were apparent only for CO and NOx running emissions. In the remaining cases, 

no significant relationships between exhaust emissions and RVP were apparent, either linear or 

quadratic. 

In the case of CO start emissions, models were fit with and without the quadratic term, 

and the difference in projected emissions estimated at 7 and 13 psi for E10 gasoline. The 

differences between the two models are approximately 3% at 7 psi and 7% at 13 psi. Obviously, 

there is no suggestion of curvilinearity in the relationship between emissions and RVP for any 

the remaining emissions or test phases. 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-18

On the whole, we conclude that the available evidence gives no suggestion of strong 

curvilinearity in the relationship between RVP and logarithms of emissions. Accordingly, 

pending further evidence, we consider it reasonable to extrapolate these trends linearly from the 

“summer RVP range” (7-10 psi) to the “winter range” (10-13 psi).

Table 3-3 Summary of statistical modeling of ethanol and RVP effects on FTP emissions (Source: CRC E-74b, 

results measured at 75 F on E0 and E10 fuels)

Emission Phase Model term

Ethanol RVP RVP×RVP Ethanol×RVP

CO 1 ● --- ● ---

2 ● ● --- ---

HC 1 ● --- --- ---

2 ● --- --- ---

NOx 1 --- --- --- ---

2 --- ● --- ---
Tier 3 Summary and Analysis of Comments

3-19

Figure 3-7 CO emissions vs. RVP at 75°F, measured on the FTP cycle (Source E-74b)

(a) Cold-Start (Bag 1)

(b) Hot-Running (Bag 2)

92 For example, winter season RVP caps for controlling CO exhaust.
Chapter 3: Emissions and Air Quality Emissions Impacts

3-20

93 This may be due to the limited temperatures evaluated (50 and 75 degrees Fahrenheit).

Figure 3-8 THC emissions vs. RVP at 75°F, measured on the FTP cycle (Source E-74b)

(b) Hot-Running (Bag 2)

(a) Cold-Start (Bag 1)
Tier 3 Summary and Analysis of Comments

3-21

Figure 3-9 NOx emissions vs. RVP at 75°F, measured on the FTP cycle (Source E-74b)
Chapter 3: Emissions and Air Quality Emissions Impacts

3-22

With respect to the interaction between temperature and RVP, the commenter notes 

correctly that the datasets used to estimate fuel effects did not incorporate the effect of 

temperature.

At the outset, we can point out that MOVES does not apply temperature adjustments to 

hot-running CO, THC or NOx emissions, thus obviating the need to consider interactions 

between temperature and fuel effects. It is widely accepted that the effect of temperature on hotrunning gaseous emissions is negligible. 

For start emissions of CO, THC and NOx, however, MOVES applies both temperature 

and fuel effects, under an assumption that they can be applied multiplicatively and 

independently. However, when multiplicative effects are jointly applied to mass emissions (in 

“linear” as opposed to logarithmic space), the results appear “interactive” in that the different 

effects either reinforce or damp each other. For example, start emissions increase substantially 

as temperature declines, implying that fuel effects are amplified at lower temperature, whether 

positive or negative. The net result can be either increased or decreased emissions, depending on 

the nature of the fuel effects.

We can focus on start CO as an example. For CO, fuel effects are calculated using the 

Complex model for 2000 and earlier model years4, and using the EPAct models for 2001 and 

later model years. In both cases, the results applied are broadly consistent with those of the study 

cited by the commenter (CRC E-74b)5. As the two studies applied differing approaches to 

statistical analysis, the respective model coefficients cannot be compared in terms of magnitude. 

However, they may be compared qualitatively in terms of sign. 

For cold-start CO emissions (Bag 1), the Complex Model has a small but positive lineareffect coefficient for RVP. This result is directionally similar to the E-74b Composite CO model, 

which also has positive RVP coefficients, as well as a positive interaction between RVP and 

temperature. This result implies that for “cold” temperatures below 50°F, increasing RVP should 

increase CO, with the effect amplified by decreasing temperature. The application of the 

Complex Model in MOVES gives qualitatively similar results with a positive RVP coefficient 

amplified by the multiplicative temperature adjustment. 

For MY2001 and later, the EPAct models can be applied to start emissions specifically. 

The CO start model has a negative linear coefficient for RVP, (meaning that emissions decline as 

RVP increases). In E-74b, a piece-wise fit was used, giving negative and positive coefficients for 

RVP < 9 and > 9 psi, respectively. In addition, a positive interaction term was included in the 

reduced model (Table 5-14, page 64). As expected, the temperature coefficient is negative, 

suggesting that an “interference” interaction applies, i.e., that the combined effects of RVP and 

temperature would have a mutual “damping” effect. The net results of the E-74b model are 

shown in Figure 5-1 (page 76) of the CRC report. At temperatures below 50 °F, the trends 

portrayed show an “interference” effect, i.e., that increasing RVP decreases CO start emissions, 

 

4

For THC and NOx, analogous effects are calculated using applications of the EPA Predictive Model.

5 Coordinating Research Council. Effects of Vapor Pressure, Oxygen Content, and Temperature on CO Exhaust 

Emissions. CRC Report E-74b. Alpharetta, Georgia, (Prepared by Sierra Research, Inc. Sacramento, CA), May, 

2009.
Tier 3 Summary and Analysis of Comments

3-23

with the absolute margin (in g/mi) increasing with declining temperature. As mentioned, despite 

the differences in underlying data and modeling approaches, the application of independent RVP 

and temperature effects in MOVES gives similar results. This outcome results from the 

multiplicative combination of a negative temperature effect (CO increases and T decreases) with 

a negative RVP effect (CO decreases as RVP increases). The net result is that the temperature 

effect is reduced by increasing RVP at lower temperatures, which is directionally similar to the 

result obtained in E-74b, and suggested by the commenter as a correct representation of CO 

behavior in relation to RVP and “cold” temperature. 

Results for THC and NOx are similar. The models applied in MOVES do not contain 

temperature effects, but multiplicative combinations of the fuel and temperature effects results in 

interaction effects in the projected emission volumes. Thus, on the whole, we conclude that the 

multiplicative combination of temperature and fuel effects as applied in MOVES does allow for 

interactions between these effects.

What Commenters Said:

EPA assumes that the proposed evaporative emission standards reduce permeation emissions by 

75%, emissions from vapor leaks by 70%, and emissions from liquid leaks by 30-45%. These 

assumptions are based on simple engineering estimates and are uncertain. 

Our Response:

The evaporative emissions modeling for the FRM has been significantly updated based 

on completion of additional test programs and peer review comments. The NPRM modeling for 

the Tier 3 control case was based on an engineering analysis; the revised modeling for the final 

rule incorporates the latest data and has been improved to reflect more real-world physical 

processes.

What Commenters Said:

EPA estimates that the proposed evaporative emission standards will provide 34% of the total 

VOC emission reductions expected from the Tier 3 proposal by 2030; however, the MOVES 

model does not assume any reduction in permeation emissions from Tier 2 vehicles relative to 

earlier vehicle technologies. In contrast, data from the CRC Project E-77 studies (17, 18, 19) on 

evaporative permeation show that some Tier 2 vehicles have much lower permeation emissions 

than pre-Tier 3 vehicles (e.g., vehicles certified to California’s “Zero Evaporative Emission 

Standards”). Therefore, it is likely that a portion of the assumed permeation benefit for Tier 3 

already is occurring in Tier 2 vehicles. Thus, the benefits of the proposed Tier 3 evaporative 

emission standards are overstated. 

17 - Haskew, H. and Liberty, T, Enhanced Evaporative Emission Vehicles, CRC Project E-77-2, March 

2010 

18 - Haskew, H. and Liberty, T, Vehicle Evaporative Emission Mechanism: A Pilot Study, CRC Project 

E-77, June 24, 2008 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-24

19 - Haskew, H. and Liberty, T, CRC Project E-77-2c, Study to Determine Evaporative Emission 

Breakdown, Including Permeation Effects and Diurnal Emissions Using E20 Fuels on Aging Enhance 

Evaporative Emissions Certified Vehicles, December, 2010 

Our Response:

Data from the CRC E-77 programs show that pre-Tier 2 technologies have higher 

permeation emission rates than Tier 2 vehicles. The CRC E-77 test data indicate that the Tier 2 

permeation rates in the version of MOVES used for the Tier 3 FRM analysis properly reflect the 

data, but pre-Tier 2 rates are underestimated. Our Tier 3 analysis is not ascribing emissions 

benefits to Tier 3 that are already occurring, and Tier 3 benefits are not being overstated.

What Commenters Said:

The method by which exhaust basic emission rates were developed for Tier 3 vehicles, based on 

the ratio of exhaust standards, failed to account for the different certification fuels inherent in 

those standards. 

One key concern noted was that within EPA’s ratioing method for NPRM MOVES, the 

difference in certification fuels between Tier 1 and Tier 3 vehicles was not accounted for in 

the calculation of exhaust basic emission rates. This is problematic as the differences in 

certification fuel in terms of sulfur content and oxygenate level are significant for the Tier 3 

case. Because of certification fuel differences, the application of ratios based on strict 

numeric exhaust standards is flawed if fuel differences are not explicitly factored in. 

Our Response:

We agree that this question was relevant to the NPRM MOVES analysis. However, for 

the FRM analysis, we addressed the question of changing certification fuels by incorporating fuel 

adjustments in the “GeneralFuelRatioExpression” calculations to account for the adoption of 

Tier 3 certification fuel starting in MY2017. One such adjustment accounts for reduction in fuel 

sulfur to 10 ppm and is calculated by re-centering the preexisting sulfur model around a new 

base sulfur calculation at 10 ppm. A second adjustment accounts for the adoption of E10 

certification fuel and is calculated modifying the existing adjustments using the EPAct models 

by assigning the Tier 3 certification fuel as the “base” fuel for MY2017 and later. With these 

adjustments in place, Tier 3 vehicles operating on in-use fuel with 10 ppm sulfur would show no 

sulfur effect, as the in-use and certification levels match. Similarly, Tier 3 vehicles operating on 

an in-use fuel with the same non-sulfur properties as the Tier 3 certification fuel would have no 

fuel adjustment for the non-sulfur fuel properties. Conversely, emissions for Tier 3 vehicles 

operating on fuels with properties differing from the E10 certification fuel are adjusted 

appropriately relative to the certification fuel.

What Commenters Said:
Tier 3 Summary and Analysis of Comments

3-25

In order to capture the potential emissions effects of reducing gasoline sulfur levels below 30 

ppm, a separate equation was developed for use in the EPA mobile source emissions inventory 

model, MOVES. This equation was based solely on the EPA study of sulfur effects on exhaust 

emissions of in-use Tier 2 light-duty vehicles. The coefficients applied to this equation were 

from mixed model results with inherent assumptions which were acknowledged within the in-use 

sulfur report (see comments below). The sulfur effects were then applied multiplicatively to 

other gasoline fuel effects in MOVES. EPA did not provide a comparative analysis of expected 

emissions impacts due to the sulfur equation change in MOVES. 

Our Response:

The estimated emissions impacts from the updated sulfur model are presented in a 

separate memorandum to the docket.6

3.1.1.1. Additional Comments from Sierra Research Submitted as a Part of 

API/AFPM Comments

What Commenters Said:

An assessment of the emissions benefits of the Tier 3 proposal was prepared by Sierra Research 

and attached to API/AFPM’s comments (Attachment No. 13).

The linear correction factor implemented in NPRM MOVES conflicts with the EPA analysis of

the in-use sulfur program to develop the percent changes. 

Our Response:

As described in a separate memo to the docket7, since the results from the in-use sulfur 

program based on log-transformation were reverse-transformed to linear space prior to being 

incorporated into MOVES, we believe that the percent changes from the mixed model were 

correctly applied. Furthermore, the relationship between changes in gasoline sulfur content and 

NOx, HC, NMHC and NMOG emissions is typically linear. The linearity of sulfur impacts on 

NOx, NMHC and NMOG emissions is supported by past studies with multiple fuel sulfur levels 

all of which compare gasoline with differing sulfur levels that are below approximately 100 ppm 

(e.g., CRC E-60 and 2001 AAM/AIAM programs as well as comments submitted to this 

rulemaking by MECA cited within Preamble IV.A.6). As stated within Preamble IV.A.6 of the 

Tier 3 final rule, the relative linearity of the effect of gasoline sulfur level on NMOG and NOx 

emissions allows exhaust emissions results generated within EPA and other studies of gasoline 

sulfur at levels immediately above or below either 10 ppm or 30 ppm to be normalized to either 

10 ppm sulfur or to 30 ppm sulfur. This allowed EPA to evaluate vehicle emission control 

 

6 U.S. EPA. 2014. Memorandum to Docket: Updates to MOVES for the Tier 3 FRM Analysis

7 U.S. EPA. 2013. “Memorandum to Docket: Updates to MOVES for the Tier 3 NPRM”
Chapter 3: Emissions and Air Quality Emissions Impacts

3-26

system response to changes in gasoline sulfur content either between or within the range defined 

by the proposed level of 10 ppm S and the current standard of 30 ppm S.

What Commenters Said:

The NPRM MOVES sulfur correction update for light-duty Tier 2 vehicles does not account

for the difference between normal and high-emitting vehicles, whereas distinct sulfur impacts 

for normal and high emitters are accounted for in the preexisting MOVES sulfur corrections 

for 2003 and older model year vehicles.

68 The average odometer of the in-use test program on 

which this update is based is about 30,000 miles compared to an approximate odometer level 

of 120,000 miles for the average on-road vehicle.

69 Therefore, this new method is biased high 

due to absence of a high emitter adjustment in NPRM MOVES given that the test fleet on 

which it is based is newer than the average in-use fleet. This issue of high emitters should 

have been apparent to EPA, as previous sulfur studies have evaluated both new and aged 

catalysts given the clear importance of the representativeness of the vehicle catalyst.

70, 71 

68 High emitters are generally less sensitive to fuel sulfur content.

69 As per Footnote 43, the average vehicle in the on-road light-duty fleet is 10.8 years old (calendar year 2011

estimate) with an approximate odometer reading of just under 120,000 miles.

70 T. D. Durbin, J. W. Miller, J. T. Pisano, T. Y. Younglove, C. G. Sauer, S. H. Rhee, T. Huai, and G. I. MacKay,

“The Effect of Fuel Sulfur on NH3 and Other Emissions from 2000-2001 Model Year Vehicles, CRC Project E60,” May 2003, available at www.crcao.com.

71 “Summary: CRC Sulfur/LEV Program,” Coordinating Research Council Report, CRC Project No. E-42, December

22, 1997.

Our Response:

The commenter claimed that the absence of high emitter adjustment for 2004-and-later 

vehicles in MOVES would result in overestimation of the effects of sulfur on emissions based 

on two studies. However, we do not believe that these studies provide support for the 

commenter’s claim. The first study by Durbin et al. concluded that for both NMHC and NOx, 

the effects of catalyst age on FTP composite emissions were not statistically significant for the 

tested fleet. The CRC Sulfur/LEV study showed that when sulfur was reduced from 600 to 40 

ppm, aged catalysts demonstrated slightly lower but similar magnitudes of sulfur effect on 

FTP composite emissions as compared to the new catalysts. 

What Commenters Said:

The correction factors listed in Table 6-2 for “all other types” represent those applied by the

model for heavy-duty gasoline vehicle types. The documentation wholly omits any discussion 

of the derivation of these values. EPA needs to document how these values were derived 

before they can be reviewed.

Our Response:
Tier 3 Summary and Analysis of Comments

3-27

The MOVES docket memo for the Tier 3 FRM analysis8presents the derivation of the 

sulfur coefficients for heavy-duty gasoline vehicles.

What Commenters Said:

For motorcycles, the method assumes no impact from fuel sulfur (see Table 6-2). EPA has no 

data from motorcycles on fuel sulfur effects; however, for model years 2003 and older, the model 

maps motorcycle fuel corrections to those of light-duty gasoline vehicles. So in this instance, 

the new method (to have no sulfur impact for motorcycle exhaust) is inconsistent with the

method applied to all other model year motorcycles. This is a minor point since the contribution 

of motorcycles to the on-road inventory is minor.

Our Response:

In modeling the emissions impact from the proposed rule, we did not attempt to update 

the fuel sulfur algorithm in MOVES for the legacy vehicles (pre-2004 model year vehicles) 

including motorcycles, since (as the commenter pointed out) the emissions contribution from 

them is very small. The contribution of pre-2004 model year motorcycles to the on-road 

inventory for all criteria pollutants is less than 0.5% in 2018 and less than 0.1% in 2030. In 

terms of the total Tier 3 emission reductions, pre-2004 model year motorcycles account for 0.1% 

and 0.0% of the Tier 3 emission reductions in 2018 and 2030, respectively, for all criteria 

pollutants. For 2004-and-later model year vehicles, the fuel sulfur algorithm was updated based 

on the latest data from the in-use sulfur program only for cars and trucks. We believe that the 

changes in assumption of no sulfur impact for 2004-and-later model year motorcycles is justified 

due to lack of data and because both methodologies result in consistent outcome of almost no 

impact of fuel sulfur from motorcycles on national emissions inventories.

What Commenters Said:

The model inappropriately extrapolates log-log sulfur corrections towards the zero asymptote for 

key sectors of the 2003-and-older model year fleet in order to evaluate proposed sulfur 

requirements. The result is large changes in exhaust emissions that are not confirmed by actual 

data. 

NPRM MOVES incorporated no new data for estimating 2003 and older model year vehicle

fuel sulfur impacts. In order to evaluate fuel sulfur levels at or below 10 ppm as part of the

regulatory evaluation, the model simply extrapolates preexisting sulfur adjustment equations 

present in the public version of MOVES. Thereby, the NPRM MOVES model methods are

that of MOVES2010a with one minor change. Because this sulfur correction is an 

extrapolation (most of the underlying methods developed did not contain any fuels below 30 

ppm S, see Table 6-5), EPA programmed in a cap at the maximum allowable exhaust reduction 

due to sulfur below 30 ppm. In MOVES2010a that cap is 15 percent (defined relative to 30 

 

8 U.S. EPA. 2014. Memorandum to Docket: Updates to MOVES for the Tier 3 FRM Analysis, Chapter II.A.
Chapter 3: Emissions and Air Quality Emissions Impacts

3-28

ppm fuel); in NPRM MOVES that cap is 60 percent (defined relative to 30 ppm fuel).

72 

EPA’s justification is that the in-use sulfur test program with Tier 2 vehicles showed reductions 

up to 60 percent; therefore, greater reductions should be permissible when extrapolating

previous test programs beyond the lower sulfur limit tested.

Figure 6-3 presents an example of how the linear extrapolation compares to that used by

NPRM MOVES for NOx emissions from normal emitting NLEVs (passenger cars). 

Figure 6-3

NPRM MOVES NLEV (Passenger Car) Sulfur Impact

Running Exhaust NOx, Normal Emitter

72 The 15 percent cap in MOVES2010a was present, because the model already did permit the extrapolation of fuel

sulfur effects below 30 ppm as part of emission inventory development calculations.

Our Response:

In modeling the emissions impact from the proposed rule, we did not attempt to update 

the fuel sulfur algorithm in MOVES for the pre-2004 model year vehicles because we were not 

aware of any additional data that provided information on fuel sulfur below 30 ppm for the 

legacy vehicles. Therefore, the commenter is correct that the effects of sulfur for pre-2004 

model year vehicles are based on extrapolation. 
Tier 3 Summary and Analysis of Comments

3-29

However, the commenter did not accurately characterize the effect of extrapolation in the 

plot they presented above. Figure 3-10 through Figure 3-13 show the effect of sulfur on running 

exhaust emissions from pre-2004 model year vehicles for sulfur levels below 30 ppm, based on 

MOVES. The red lines represent the old sulfur floor of 15 percent, previously in MOVES2010a,

and the blue lines represent the new sulfur floor of 60 percent in Tier 3 NPRM version of 

MOVES. For all pollutants, the lines lie on top of each other for sulfur level at or above 10 

ppm, the average in-use sulfur level modeled in the Tier 3 rule. The two lines start to diverge 

only below 10 ppm. These trends are also true for the sulfur effects on starts. The plots indicate 

that the modification made to the sulfur floor in the Tier 3 NPRM version of MOVES did not 

affect the sulfur adjustment and thus, did not impact the emissions inventories estimated in the 

rule. 

Lastly, the effects of lowering sulfur level on emission for pre-2004 model year vehicles 

are less than 2% for all criteria pollutants in both 2018 and 2030, contrary to the commenter’s 

claim that the effects based on extrapolation would result in large changes. In terms of the 

emissions reductions estimated from the Tier 3 standards, the contribution from pre-2004 model 

year vehicles represent 4% and 8% of the total reductions in 2018 for NOx and VOC, 

respectively, and 0.1% and 0% in 2030 for NOx and VOC, respectively. 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-30

Figure 3-10 Effect of sulfur on running exhaust NOx emissions from pre-2004 model year 

vehicles in MOVES
Tier 3 Summary and Analysis of Comments

3-31

Figure 3-11 Effect of sulfur on running exhaust THC emissions from pre-2004 model year 

vehicles in MOVES
Chapter 3: Emissions and Air Quality Emissions Impacts

3-32

Figure 3-12 Effect of sulfur on running exhaust CO emissions from pre-2004 model year 

vehicles in MOVES
Tier 3 Summary and Analysis of Comments

3-33

Figure 3-13 Effect of sulfur on running exhaust PM2.5 emissions from pre-2004 model year 

vehicles in MOVES

What Commenters Said:

The 2003 and older model year methods assign light-duty corrections directly to motorcycles

and heavy-duty vehicles. The method assumes all sulfur impacts are equivalent across vehicle

classes mapped by model year. Therefore, the sulfur correction for a 2003 model year light-duty

vehicle (meeting the NLEV standard) is that applied by the model to a 2003 motorcycle and a

2003 heavy-duty gasoline vehicle. The lack of vehicle class specific impacts is problematic for

motorcycles and heavy trucks as the underlying data are based on light-duty gasoline vehicles 

only (and the catalyst technology employed is not constant across vehicle classes for any given 

model year). This lack of vehicle class specificity is inconsistent with the 2004 and later model

year approach that has distinct corrections by vehicle class as shown in Table 6-2.

Our Response:

We believe that the modeling approach that applies distinct sulfur effects by vehicle type 

for 2004-and-later model year vehicles is an improvement over what was done previously. We 

acknowledge that the fuel sulfur effect for pre-2004 model year motorcycles and heavy-duty 

gasoline vehicles were based on the effect from light-duty vehicles, but we do not expect the 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-34

effect of sulfur on heavy-duty gasoline vehicles to be significantly different than that of lightduty since the combustion and exhaust aftertreatment systems are similar in principle. The 

impact on emissions is minimal; the contributions to the total inventory from pre-2004 model 

year motorcycles and heavy-duty gasoline vehicles are less than 1.8% in 2018 and 0.1% in 2030

for VOC and NOx. Again as previously explained, when using predictive models to support 

rules, EPA has to make judgments regarding what modeling information is available and whether 

the information is of adequate quality to support the conclusion being reached.

What Commenters Said:

EPA revised the estimated proportion of fuel sulfur emitted as exhaust sulfate PM for NPRM 

MOVES. The exhaust sulfate PM is the only exhaust PM component impacted by fuel sulfur. 

The revised approach basically halved the amount of fuel sulfur coming out as exhaust sulfate. 

The sulfate correction to PM exhaust was not developed using data below 30 ppm and was a

linear extrapolation assuming no lube oil contribution as the method presumes no sulfate

exhaust at zero ppm S fuel. The method should address the sulfate component due to lube oil, 

especially at ultra-low sulfur levels assumed. However, this methodological issue is a minor

point as the sulfate portion of PM exhaust is minor.

Our Response:

Due to limited data on lubricating oil contributions to fuel sulfur for gasoline vehicles, 

and the small contribution of sulfate to PM from gasoline vehicles (as the commenter pointed 

out), no changes were made to the methodology for modeling sulfate emissions in the final rule.

What Commenters Said:

Finally, EPA’s analysis of the In-Use Study data suggests that there is no effect of gasoline 

sulfur content on PM emissions. However, the MOVES model used by EPA to compute the 

benefits of the proposed Tier 3 regulation assumes that reducing sulfur content will reduce PM 

emissions.

Our Response:

No sulfur effect on PM emissions was modeled in MOVES for Tier 2 and later vehicles, 

consistent with the results from the In-Use Sulfur Program.

What Commenters Said:

All NLEV through Tier 3 exhaust basic emission rates are ratioed from Tier 1 vehicles in 

MOVES. Ratios are separate for low-to-mid power range (ratioed to FTP) and high power range

(ratioed to US06). These power ranges were illustrated previously in Figure 6-1. Tier 1 was the

latest technology for which EPA felt it had a full enough record of data across the vehicle useful 
Tier 3 Summary and Analysis of Comments

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life to estimate deterioration in the original release of MOVES2010. For NPRM MOVES, no 

attempt was made to update NLEV and Tier 2 basic emission rates with new data available since

the original MOVES2010 development, nor was an attempt made to validate the extrapolation 

assumptions such as the proportions of emissions by exhaust mode and deterioration rates.

96 

94 J. Warila, “Developing Emission Rates Representing the Effect of Proposed Tier 3 Standards on Gaseous 

Emissions from Gasoline-Powered Light-duty Vehicles (HC/CO/NOx),” EPA OTAQ memorandum to the 

Docket Number EPA-HQ-OAR-2011-0135, December 2011.

95 “Development of Emission Rates for Light-Duty Vehicles in the Motor Vehicle Emissions Simulator

(MOVES2010),” EPA-420-R-11-011, August 2011.

Our Response:

As the MOVES documentation

9

and docket memorandum

10 make clear, emission rates 

for NLEV, Tier 2 and Tier 3 vehicles are scaled relative to rates for Tier 1 vehicles, with scaling 

factors assigned using FTP and US06 results from the In-use Verification Program. As the 

documentation also describes, we estimate deterioration for these vehicles using proportional 

scaling applied by a log-linear trend (through nine years of age), in which slopes in 

ln(Emissions) are assumed to be similar. Beyond nine years, deterioration is assigned through a 

set of proportional factors. Based on examination of large volumes of data for Tier 1 and earlier 

vehicles, we believe that this assumption is reasonable. Note that under these multiplicative or 

“logarithmic” assumptions, late-model year (e.g., 2013) vehicles show much lower absolute 

deterioration than previous model year (e.g., 2001) vehicles; that is, the late-model year vehicles 

have much less absolute increase in the average emission rate over a given period of time (in 

g/hr, g/mi, etc.). In addition, the multiplicative deterioration model, which we believe to be 

technically appropriate, assigns far lower deterioration to Tier 2 or Tier 3 vehicles than some 

alternative models, such as assuming that deterioration in start emissions could be estimated as a 

fixed additive increment. Again, the consistent patterns in multiplicative scaling seen in data for 

Tier 1 and earlier vehicles give a reasonable expectation that similar patterns would apply to 

NLEV and Tier 2 vehicles.

With regard to assumptions regarding the proportions of emissions in various operating 

modes, we disagree that we “extrapolate” these assumptions in developing emission rates. In 

fact, the questions of time fraction in operating modes and the emission rates for differing 

technologies do not intersect. As the operating modes for running operation are defined in terms 

of speed and acceleration, rather than vehicle technology or emissions standards, they are 

influenced by vehicle weight and driving patterns. We would not expect changes in rates, 

however they are assigned, to give associated changes in operating–mode fractions.

What Commenters Said:

 

9 U.S. EPA. 2011. Development of Emission Rates for Light-Duty Vehicles in the Motor Vehicle Emissions 

Simulator (MOVES2010). EPA-420-R-11-011. Assessment and Standards Division, Office of Transportation and 

Air Quality, Ann Arbor, MI. 

10 U.S. EPA. 2013. “Memorandum to Docket: Updates to MOVES for the Tier 3 NPRM”
Chapter 3: Emissions and Air Quality Emissions Impacts

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EPA updated estimates of the impact of fuel system leaks on evaporative emissions using data

from a Colorado field program. This program provided data on the incidence of vehicles with 

leaks in the evaporative emission control system and in emissions associated with these vehicles. 

While this database is suitable for use in updating emission inventories, there remains 

considerable uncertainty in projecting emissions associated with “leakers” due to uncertainty in 

incidence and emission impact of leakers. This leads to uncertainty in projected evaporative

emissions and benefits of the Tier 3 proposal.

Our Response:

The analysis and report determining the leak prevalence rates underwent significant 

revisions between the NPRM and FRM and was therefore sent out for a second peer review. The 

second review did not result in revisions to the analysis, but did have some minor updates to the 

report.11 The analysis revisions included uncertainties for prevalence rates and are shown in the 

report. 

What Commenters Said:

Vapor venting algorithms used to estimate evaporative emissions for multi-day diurnals and for

vehicles with leaks were updated for the Tier 3 analysis with the DELTA model. Although the

model is an improvement over the previous method of estimating vapor growth by accounting for

canister capacity, back purge, and multiple day diurnals, a peer review found weaknesses in the

model, most importantly in assumptions about evaporative canister back-purge,

100 which leads to 

additional uncertainties regarding EPA’s estimates of evaporative emission benefits for the Tier 3 

proposal.

Our Response:

For the NPRM, EPA used an estimate for back-purge based on a marine study. The 

FRM modeling, using the DELTA model for diurnal emissions, now includes a revised backpurge estimate based on the completed multi-day diurnal test program of nine vehicles 

representing top sales of the national fleet, tested over fourteen days of diurnals in a SHED.12

What Commenters Said:

As part of the NPRM MOVES development, EPA reviewed the permeation impact of ethanolcontaining gasoline. EPA’s evaluation found, based on several CRC studies

103 that the

permeation impact for E15 is not statistically different from E10. The conclusion that ethanolrelated permeation impact does not vary by ethanol content (for the range of

 

11 DeFries, T., Palacios, C., Weatherby, M., Stanard, A., Kishan, S. (2013) Estimated Summer Hot-Soak 

Distributions for Denver’s Ken Caryl I/M Station Fleet.

12 Lindner, J, Sabisch, M., Glinsky, G., Stewart, J., St. Denis, M., Roeschen, J. (2013) Multi-Day Diurnal Testing
Tier 3 Summary and Analysis of Comments

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6 to 20 percent by volume) is supported by the CRC studies and the review completed as part of

CRC Project A-73-1.

104 Given this finding, NPRM MOVES used the previously estimated E10 

permeation impact for E15 gasoline in the RIA methods.

105

101 “Mobile Source Hydrocarbon Speciation Profiles for the Tier 3 Rule NPRM and Anti-backsliding Study

AQ Modeling,” U.S. EPA memorandum, Docket EPA-HQ-OAR-2011-0135, January 2013.

102 “Hydrocarbon Composition of Gasoline Vapor Emissions from Enclosed Fuel Tanks – Draft,”, EPA420-R-11-018, 2011.

103 M. Beardsley, “Updates to MOVES for the Tier 3 NPRM Analysis,” EPA OTAQ memorandum to the

Docket Number EPA-HQ-OAR-2011-0135, March 2013.

104 “Development of Inventory and Speciation Inputs for Ethanol Blends,” CRC Report No. A-73-1, Report

No. SR2012-04-01, prepared by Sierra Research for Coordinating Research Council, May 2012.

105 It was noted that the NPRM MOVES memorandum contained a typo for the discussion on this subject matter.

The memo reports the ethanol permeation increase for vehicles meeting enhanced evaporative

standards (and newer) as “213 percent increase for newer technology vehicles.” The correct value used by

the model is an increase of 113.8 percent (or a multiplicative adjustment of 213.8).

There are two aspects, outlined below, in which the model’s permeation impacts due to 

ethanol could be improved upon.

1. If the permeation impacts of E6 to E20 are not statistically different, then the 

modeled permeation increase could be based on the data collected from all ethanol 

blends. The NPRM MOVES impact is based only on E6 to E10 fuels.

Our Response:

Analysis of the E-77 program using this approach (including E6-E20 fuels) affects the 

ethanol effect on permeation by less than 10%. This will have very small effects on modeling 

results.

2. An examination of the available data shows that vehicles meeting Tier 2 or LEV II

evaporative standards are statistically distinct from vehicles meeting enhanced 

evaporative standards. The NPRM MOVES treats all vehicles meeting enhanced 

evaporative and subsequent standards as a single group.

Our Response:

Performing a mixed-model regression on all data available from E-77 test programs 

shows no significant interaction effect for vehicle standard and ethanol.

13 The version of 

MOVES used for the Tier 3 final rule’s analysis continues to treat all vehicles meeting enhanced 

evaporative and subsequent standards as a single group with regard to the effect of ethanol in 

fuel.

What Commenters Said:

 

13 U.S. EPA, 2014, “Development of Evaporative Emissions Calculations for Tier 3 FRM” memorandum to the Tier 

3 docket.
Chapter 3: Emissions and Air Quality Emissions Impacts

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CRC A-73-1 completed the analyses to address (1) and (2) above. The analyses showed that the

presence of ethanol in gasoline increased permeation by 116 and 75 percent, respectively, for

vehicles certified to enhanced evaporative and Tier 2/LEV II standards. This compares to the 114

percent increase modeled by NPRM MOVES for both sets of standards. As such, the NPRM 

MOVES ethanol permeation impact is overstated for the newest technology vehicles. 

Our Response:

Our analysis differs from A-73-1

13. We did not find a statistical significance in ethanol 

effects for different vehicle standards in the E-77 data sets whether we use the E20 tests or not in 

the analysis. 

What Commenters Said:

Commenter: Governors’ Biofuels Coalition

EPA must ensure that its fuel models are updated to reflect new science and the realistic 

emissions from the combustion of commercial gasoline (as opposed to unrealistic certification 

fuels). 

Our Response:

EPA agrees with the commenter. Accordingly, the emissions model used to estimate the 

emissions reduction from the proposed rule included updated fuel-effects model incorporating 

the latest researches on the effects of fuel properties on on-road emissions.14,15,16

What Commenters Said:

Commenter: Pennsylvania Department of Environmental Protection (DEP)

Nevertheless, DEP has concerns about ... potential gaps or flaws in the emissions modeling.

Our Response:

EPA disagrees with the assertion that there are potential gaps or flaws in the emissions 

modeling, especially since the commenter did not provide any detail about the areas of concern. 

 

14 U.S. EPA, 2013. Assessing the Effect of Five Gasoline Properties on Exhaust Emissions from Light-Duty 

Vehicles certified to Tier 2 Standards: Analysis of Data from EPAct Phase 3 (EPAct/V2/E-89). Final Report. EPA420-R-13-002. 

15 The Effects of Ultra-Low Sulfur Gasoline on Emissions from Tier 2 Vehicles in the In-Use Fleet, EPA-420-R-14-

002.

16 U.S. EPA. 2014. Memorandum to Docket: Updates to MOVES for the Tier 3 FRM Analysis
Tier 3 Summary and Analysis of Comments

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Again as previously explained, EPA recognizes that any modeling analysis, and any projection 

of future conditions, inherently has uncertainties. But “[i]t is only when the model bears no 

rational relationship to the characteristics of the data to which it is applied that [courts] will hold 

that the use of the model is arbitrary and capricious.” Appalachian Power Company v. EPA, 135 

F.3d 791, 802 (D.C. Cir. 1998)(internal citations omitted). 

What Commenters Said:

The EPA should explain in greater detail the methodology for obtaining the emission reduction 

estimates that would immediately occur when 10 ppm sulfur average levels at the refinery gate 

become available to the nation’s fleet.

Our Response:

We disagree with the commenter that our methodology for estimating emissions 

reductions from 10 ppm sulfur was not adequately explained. Our modeling methodology is 

clearly documented in Chapter 7 of the RIA, and the Emissions Modeling Technical Support 

Document. The underlying peer-reviewed study of the effects of sulfur on Tier 2 vehicles are 

described in Section IV of the Preamble and in Chapter 1 of the Regulatory Impact Analysis.

Furthermore, the memorandum to the docket on updates to MOVES describes how the results 

from the in-use sulfur study were incorporated into the MOVES model used for the air quality 

and inventory analyses.

What Commenters Said:

Aviation fuel; gasoline subject to the averaging, banking, and trading program; diesel fuel; and 

home heating oil in the liquid fuels transportation network all can lead to contamination of Tier 3 

gasoline. As EPA states in the proposed rule in reference to a 10 ppm cap, ‘The U.S. gasoline 

distribution system poses contamination challenges that make it difficult to set and enforce such 

a tight downstream per-gallon sulfur standard.’ (78 FR 29927). It is quite possible during the first 

three years of this program that the 10 ppm refinery gate average could be much higher 

downstream of the refinery when the fuel reaches the Northeastern United States. The EPA 

should explain what will be the average downstream level of sulfur in gasoline available to the 

motoring public and indicate that the emissions modeling is based off this realistic sulfur level. 

As indicated in the previous comment, even levels of sulfur near 15 ppm will have deleterious 

effects on gasoline. Further, fuels available in terminals in Pennsylvania today exceed the current 

30 ppm Tier 2 sulfur fuel standard. Some gasoline sulfur levels in Pennsylvania approach 50 

ppm. The modeled emission reductions and monetized health benefits should be based on what 

gasoline sulfur level will actually reach the consumer. 

The EPA should verify the accuracy of the emissions modeling results if intra-company sulfur 

credit trading is allowed. If refineries can use intra-company sulfur credit trading, how does the 

varying average sulfur content of gas affect modeling assumptions? It seems likely that gasoline 

sulfur levels will vary largely by producer, region, and even batch. If the average sulfur content 

varies widely, emission reductions could vary widely by region which means that some areas 

will not achieve the reductions promised by this program while other achieve higher reductions 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-40

than promised. This is important to quantify to allow an accurate representation of the monetized 

benefits.

Our Response:

The emissions modeling assumed 10 ppm sulfur everywhere nationwide, because there is 

too much uncertainty associated with the individual refinery compliance decisions and the 

movement of fuel through the fuel distribution system to predict in-use sulfur levels in specific 

geographic areas. This is consistent with our expectation of what the national average in-use 

sulfur levels will be at retail. Potential contamination downstream of the refinery, or increases in 

sulfur due to small volume additives are expected to be minor, and offset by minor downstream 

decreases from downstream blending of lower sulfur blendstocks. As the commenter notes, the 

averaging, banking, and trading program means that some gasoline could be above 10 ppm sulfur 

and some gasoline could be below 10 ppm sulfur. However, because refineries generating 

credits and using credits are interspersed across the country, and because most areas receive a 

considerable portion of their fuel by pipeline, barge, rail or truck from refineries in other areas, 

we expect the variation in average sulfur levels across the country to be limited. 

EPA is committed to monitor and further evaluate in-use sulfur levels and their impact on 

vehicle emissions. Such ongoing evaluation will include analyses of: in-use fuel surveys; batch 

data that refineries are required to submit; and the sulfur credit market. It will also include 

evaluation of any issues or concerns that might arise during implementation of the program. 

Finally, we will also carry out an ongoing evaluation of data submitted by the vehicle 

manufacturers on the performance of their Tier 3 vehicles in-use.

3.1.2. Criteria and Toxic Pollutant Emission Impacts

What Commenters Said:

Commenter: Chevron Products Company

Impact on Emissions and Air Quality: The NPRM indicates that by 2050, the proposed Tier 3 

program would reduce NOx and VOC emissions by nearly 40% from the level of emissions 

projected without Tier 3 controls. Missing from EPA’s assessment is a reference point that 

allows the comparison of Tier 3 to other similar control measures. Although a 40% reduction is 

large on a percentage basis, this reduction is off of a relatively low Tier 2 baseline, and it gives 

the reader an incomplete picture of the absolute emissions reductions from the proposal. 

Our Response:

In Chapter 7 of the Regulatory Impact Analysis for the proposal, in addition to providing 

the reduction in percent space, the estimates of absolute emissions reductions (in U.S. Short 

Tons) were also presented.
Tier 3 Summary and Analysis of Comments

3-41

What Commenters Said:

Commenter: Refinery Automation Institute, LLC

1) Using EPA’s own Complex Model Phase 2 tool, the decrease in going from the current 30ppm

S to 10 ppm S in the levels of VOC, Toxics, and NOX is very small, less than 1% (Attachment 

I).

Our Response:

We disagree with the comment. To estimate the emissions reduction from the Tier 3 

standard, substantial updates have been made in MOVES, including replacing the Complex 

Model with a new fuel-effects model for 2001-and-later model year vehicles, based on recent

research on the effects of fuel properties on on-road emissions.17,18,19 However, for pre-2001 

model year vehicles, the Complex Model is still used. Based on the model results, we expect 

substantial emissions reductions in many harmful pollutants with the Tier 3 rule (see Section III 

of the preamble to the final rule). 

3.1.3. Greenhouse Gas Emission Impacts

What Commenters Said:

Commenter: Environmental Defense Fund (EDF)

Tier 3 Rule Will Result in a Net Decrease in GHG Emissions:

EPA has estimated that the proposed Tier 3 standards will result in net GHG reductions. The

proposed sulfur and tailpipe standards are projected to reduce nitrous oxide and methane 

emissions, which are both potent greenhouse gases. Higher energy use will be required to 

remove sulfur at refineries, which will marginally increase CO2 refinery emissions, but this 

modest increase is expected to be offset by reductions in vehicle emissions of more potent 

greenhouse gases, including nitrous oxide and methane. 

Our Response:

EPA agrees that Tier 3 will result in a net decrease in GHG emissions.

 

17 U.S. EPA, 2013. Assessing the Effect of Five Gasoline Properties on Exhaust Emissions from Light-Duty 

Vehicles certified to Tier 2 Standards: Analysis of Data from EPAct Phase 3 (EPAct/V2/E-89). Final Report. EPA420-R-13-002. 

18 The Effects of Ultra-Low Sulfur Gasoline on Emissions from Tier 2 Vehicles in the In-Use Fleet, EPA-420-R-14-

002.

19 U.S. EPA. 2014. Memorandum to Docket: Updates to MOVES for the Tier 3 FRM Analysis
Chapter 3: Emissions and Air Quality Emissions Impacts

3-42

What Commenters Said:

Commenter: Marathon Petroleum Company LP (MPC)

In section III B.7., EPA states that ‘We do not expect the Tier 3 vehicle standards to result in any 

discernible changes in vehicle CO2 emissions or fuel economy.’ This is because EPA assumes 

that all the increased refinery GHG emissions will be offset by N2O and CH4 reductions in 

tailpipe emissions. EPA estimates refinery GHG emissions to be 4.6 MMTCO2e for 2017. EPA 

attempts to downplay this estimate but if their refinery by refinery model is as accurate as they 

claim, there can’t be much downside to this estimate.

Our Response:

The EPA statement that is quoted in this comment is referring to per-vehicle CO2

emissions and vehicle fuel efficiency. We are not aware of any technological reasons that vehicle 

emission controls responding to the Tier 3 vehicle standards would affect vehicle CO2 emissions 

or fuel economy in any significant way.

As the commenter notes, we also considered the CO2 emissions from refineries, and the 

non- CO2 greenhouse gas emissions (CH4 and N2O) from vehicles. We believe that the potential 

increase in GHG emissions from the Tier 3 standards would primarily come from refinery 

emissions. However, we expect the combined impact of CH4 and N2O emission reductions from 

the vehicles and CO2 emission increases from the refineries would result in a slight net decrease 

on a CO2-equivalent basis in 2018, and by 2030 a larger net decrease of between 2.5 to 2.7 

MMTCO2e (see Section III of the preamble for additional detail). 

What Commenters Said:

Commenter: WE ACT for Environmental Justice

And last but certainly not least, the importance of this rule on climate change. While the rule

documentation specifically states that an increase or decrease in greenhouse gas emissions 

cannot be ascertained with certainty at this point because of the expected emissions increases in 

the refinery process to reduce the amount of sulfur in the fuel, what you are proposing here will 

ultimately, whether now or in the near future, reduce GHG emissions. As an engineer that 

worked in refineries and many other chemical facilities, I am confident that technology will 

advance accordingly so we can say - with confidence - that one day, there will be a net reduction 

in CO2 emissions and subsequently a net reduction in negative health impacts. That is why it is 

especially important that we take every step to improve our air quality, especially for those that 

suffer respiratory and cardiovascular challenges during extremely hot weather or periods of ‘heat 

waves’ that we will continue to experience more frequently due to our changing climate.

Our Response:

We appreciate the comment. We expect the combined impact of CH4 and N2O emission 

reductions from the vehicles and CO2 emission increases from the refineries to show a slight net 
Tier 3 Summary and Analysis of Comments

3-43

decrease in 2018 on a CO2 equivalent basis. While still small, this net decrease grows to a range 

between 2.5 to 2.7 MMTCO2e by 2030. 

3.2. Air Quality Impacts of the Proposed Program

3.2.1. January 1, 2017 Implementation is Not Necessary To Help Areas Attain the Ozone 

NAAQS

We received comments reflecting two views: 1) that the standards, in the proposed timeframe, 

are not needed by states and others to attain the NAAQS; and 2) that the standards are important 

to the states for attaining the NAAQS and that the proposed timing is relevant for them. 

What Commenters Said: 

American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum Institute 

(API) and Marathon Petroleum Company LP (MPC):

EPA asserts that reducing gasoline sulfur to 10 ppm on January 1, 2017 will have immediate 

benefits for the existing vehicle fleet by reducing emissions from Tier 2 vehicles. Even if that is 

true, that does not justify January 1, 2017 implementation of the 10 ppm gasoline sulfur standard.

Furthermore, implementing the rule on January 1, 2017 will not help nonattainment areas reach 

attainment. For the current ozone NAAQS (promulgated in 2008), the Agency defined the 

classifications of nonattainment designations as: marginal, moderate, serious, severe, or extreme, 

and set deadlines for these areas to come within attainment for each category. 

The only way to attain by the end of 2015 is to have the 2013-2015 summers be clean. Similarly, 

the Moderate areas need the 2016 summer to be clean to be reclassified as attainment. Tier 3 is 

too late for the Marginal and Moderate areas. In contrast, taking EPA’s claims of emissions 

reductions benefits as true, Tier 3 could benefit the Serious, Severe, and Extreme areas, but 

January 1, 2017 implementation is not necessary to help these areas reach attainment by 

December 31, 2021. We suggest, consistent with the need to provide 5 years of lead time as 

described below, and the requirements for the Serious areas to demonstrate attainment, that EPA 

implement this rule on January 1, 2019.

The Agency claims that this proposed Tier 3 standard is necessary for States to attain the existing 

ozone NAAQS. Last year, EPA promulgated nonattainment areas for the 2008 ozone NAAQS.

Most -- 36 are marginal out of 46 total nonattainment areas -- must be in compliance by 2015 

based on monitoring data for 2013, 2014, and 2015. Tier 3 will not help these 36 marginal 

nonattainment areas because it will not be effective before 2017.

Commenter: American Lung Association of the Mid-Atlantic

Indeed, as the October 2011 report on this subject by the National Association of Clean Air 

Agencies very plainly points out, the ability of States and localities to attain the 2008 ozone 

standard is tied directly to timely promulgation and implementation of Tier 3 standards.
Chapter 3: Emissions and Air Quality Emissions Impacts

3-44

Commenter: American Lung Association Illinois

Recently the National Association of Clean Air Agencies also pointed out that the ability of 

States and localities to attain these standards is tied directly to the timely promulgation and 

implementation of Tier 3.

Commenter: Appalachian Mountain Club (AMC)

Many states, especially here in the Mid -Atlantic, may have difficulties attaining or maintaining 

the National Ambient Air Quality Standards for ozone in coming years, without Tier 3.

Commenter: Attorney General of Connecticut, et.al; Attorney General of New York, et.al

By setting more stringent emission standards for new passenger cars and trucks and cutting the 

allowable sulfur content in gasoline, the Tier 3 standards would reduce nitrogen oxides and 

volatile organic compounds by 80 percent and particulate matter by 70 percent. These reductions 

would go a long way toward limiting the production of smog. As EPA recognized, “[i]n the 

absence of additional controls, many areas will continue to have ambient ozone concentrations 

exceeding the NAAQS in the future.” 78 Fed. Reg. at 29,819.

As EPA aptly noted in the preamble to the proposed rule, “few other national strategies exist that 

would deliver the same magnitude of multi-pollutant reductions projected to result from the 

proposed Tier 3 standards.” 78 Fed. Reg. at 29,819. Therefore, we strongly support the adoption 

of the proposed Tier 3 standards and urge that they be finalized by the end of the year so that our 

States and cities may realize their benefits as soon as possible. Thank you for your consideration 

of our comments on this important matter. 

Commenter: Chicago Metropolitan Agency for Planning

However, CMAP’s actions alone will not bring the region into attainment of air quality 

standards. National action is required to bring overall mobile source emission rates down. This 

will have a significant effect both on emissions within the region and pollutants transported from 

other parts of the country. Transport in particular is a serious issue – the background monitors in 

the region are almost at the nonattainment level, indicating that out-of-region sources are a 

dominant contributor to the region’s air quality problems. 

Previous motor vehicle emission and fuel standards have had a major impact on air quality. 

Standards are becoming tighter as scientific understanding of air pollution’s impact on people 

and the environment improves, and rightly so. In order to meet the new standards, tighter motor 

vehicle emission and fuel standards are required; the proposed Tier 3 standards should be 

adopted. 

Commenter: City of Philadelphia Department of Public Health Management Services (AMS)

The Tier 3 would reduce nitrogen oxide, volatile organic compound, emission by eight and three 

percent by 2017, by 2030 by 28 and 23 percent, respectively. The approximate emission of 
Tier 3 Summary and Analysis of Comments

3-45

benzene and total air emissions would be reduced by four and three percent by 2017, and 36 and 

23 percent by 2030. These reductions will significantly improve to help benefit Philadelphians, 

and as well help us to meet the National Ambient Air Quality Standards.

Commenter: Delaware Department of Natural Resources (DNRC)

The proposed Tier 3 standards will improve the effectiveness of motor vehicle emissions 

controls and help Delaware to meet and maintain compliance with the current ozone standard 

and any potentially tighter future standard.

Delaware has been in non-attainment for the pollutant ozone since the standard was first 

established in 1971. Over the past 40 years, Delaware has reduced the impacts of ozone on our 

citizens through the adoption of numerous control measures. Delaware control measures adopted 

since 1990 have reduced ozone precursor pollutants, volatile organic compounds (VOC) and 

oxides of nitrogen (NOx), by 70%; yet Delaware’s air quality remains unhealthy. EPA has 

designated portions of the State of Delaware as non-attainment for the health based 2008 75 ppb 

ozone standard, and in 2012 Delaware’s air monitors recorded 39 exceedances of the standard, 

with one exceedance being 40% above the standard. In Delaware, mobile sources emitted 64% of 

state-wide NOx emissions for 2008.

Delaware has very limited authority to control motor vehicle emissions and fuels. As a result, 

Delaware has chosen to exercise the authority provided in Section 177 of the Clean Air and has 

adopted California’s Low Emissions Vehicle tailpipe standards, but Section 211 of the Clean Air 

Act limits Delaware’s ability to establish clean gasoline standards.

Ozone remains a major challenge, and motor vehicles are a major source of air pollution in 

Delaware, and in areas upwind of Delaware. We urge the EPA to finalize this proposal.

Commenter: Environmental Defense Fund (EDF)

More than 158 million people in the U.S. currently live in areas that have been designated as 

nonattainment for one or more of the NAAQS, which are health-based national pollution 

standards. Achieving and maintaining the NAAQS has been particularly challenging for highgrowth areas that are experiencing a significant increase in vehicle use. Tier 3 will yield 

significant emission reductions in fine particulates and ozone, improving air quality across the 

nation and assisting states in meeting their obligations under the NAAQS program.

Over 138 million people currently live in ozone nonattainment areas, which include many major 

population centers. EPA’s analysis found that decreases in ozone, likely due to tailpipe 

reductions in NOx and VOCs as a result of Tier 3 exhaust and fuel standards, will be dramatic 

enough in some areas to lower ozone levels from above the 2008 8-hour standard to below it. 

This has important implications for the 46 areas (representing 27 full or partial counties) that 

were designated as nonattainment areas in 2012 for the 2008 ozone standard. Specifically, EPA 

projects that, in 2017, ozone design values in Bucks County, Pennsylvania, Arlington County, 

Virginia, and St. Louis County, Missouri – with a total population of almost 2 million people –

will move from being above the standard to below. And by 2030, EPA has modeled that Hudson 
Chapter 3: Emissions and Air Quality Emissions Impacts

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County, New Jersey and Brazoria County, Texas – with a projected population in 2030 of over 1 

million people – will have ozone design values reduced from above the standard to below as a 

result of the proposed rule. And, in 2030, more than 200 counties are projected to have ozone 

design value (DV) decreases of greater than 1.5 ppb.

Additionally, EPA estimates that in 2030, 60 counties in the U.S. will move from above 60 ppb 

to at or below 60 ppb under the Tier 3 scenario, compared to the reference case. This indicates 

that the reductions made by Tier 3 could also be vital in helping states meet a strengthened ozone 

standard.

EPA also projects that the emissions reductions resulting from the Tier 3 program would help 

states attain and maintain the PM2.5 NAAQS. In 2030, over 100 counties are projected to have 

fine particulate design value decreases of greater than 0.05 micrograms per cubic meter.

Commenter: HEAL Utah on behalf of Jeff Miller et al:, and on behalf of Utah State Legislators

As members of the Utah Legislature, we have regularly heard from our state environmental 

regulators about the challenges they face in meeting EPA air quality standards, such as the 

National Ambient Air Quality Standards for PM 2.5. Our regulators have passed dozens of new 

rules, instituted public education programs and tightened controls on industry, yet still struggle to 

meet those standards. 

One of the main culprits, particularly for our wintertime inversion episodes, is our transportation 

sector. Our regulators estimate that 57 percent of the pollutants that plague us during those poor 

air quality winter days come from tailpipe emissions. 

Along Utah’s Wasatch Front, we have boosted investment in transit and put in place programs to 

encourage alternative fuel vehicles, such as CNG cars and trucks. Yet tailpipe emissions remain 

a significant polluter. 

Thus, it was with great interest, that we have learned of your agency’s proposed Tier 3 Vehicle 

Emission and Fuel Standards Program, which would require lower--sulfur gasoline and more 

advance vehicle pollution control systems. We believe these safeguards would have a major 

impact on Utah’s poor air quality. 

Commenter: Kentucky Division for Air Quality

Currently, Kentucky has a number of areas that need to improve air quality to meet the 2008 8-

hour ozone National Ambient Air Quality Standard (NAAQS). Tier 3 is a vital program that will 

assist urban areas in Kentucky and in other states in meeting and attaining the ozone NAAQS. 

Specifically, by 2030, the proposed Tier 3 program would result in reductions in on-road mobile 

source emissions of nitrogen oxides (NOx), volatile organic compounds (VOC) and carbon 

monoxide of at least 25 percent from current levels. Further, the Tier 3 program would reduce 

on-highway emissions of NOx and VOC nearly 40 percent by 2050, when Tier 3 vehicles would 

comprise almost the entire fleet, greatly assisting our heavily populated urban areas in realizing 

clean air. Additionally, the program would reduce sulfur dioxide (SO2) by 16,621 tons in 2017 
Tier 3 Summary and Analysis of Comments

3-47

and by 17,267 tons in 2030. Direct particulate matter (PM2.5) would be reduced by 121 tons in 

2017 and 7,458 tons in 2030.

More than 158 million people across the nation currently live in areas where the air they breathe 

violates at least one of the health-based NAAQS. Although interstate transport has in the past 

been a major contributor to air quality problems in some areas, programs and controls have been 

put in place to address this concern. Mobile source emissions, including those from the passenger 

cars and light trucks that are the focus of this proposal, are a primary contributor to these 

violations, playing an especially central role in elevated levels of ozone and fine particulate 

matter (PM2.5). The vehicles to be affected by Tier 3 standards contribute to other air quality 

problems as well, including toxic air pollution, regional haze and the eutrophication of water 

bodies. 

Commenter: Metropolitan Washington Air Quality Committee (MWAQC)

The Washington region has made great strides in cleaning the air thereby, reducing the health 

impacts of poor air quality, which cause a number of respiratory problems (e.g., asthma) and 

premature death. It has done so by lowering emissions of pollutants that produce Smog and fine 

particles in the atmosphere. As a result, the region has met the annual fine particle standards, 

which-were published in 1997 (15 μg/m3) and 2013 (12 μg/m3) as well as daily fine particle 

standards, which were published in 1997 (65 μg/m3) and 2006 (35 μg/m3). Besides this, the 

region has also met the previous 1-hour ozone standard (0.12 ppm) published in 1979. However, 

there are tougher challenges ahead for the Washington region. The region needs to meet the 

current ozone standard (0.075 ppm) by 2015 and also needs to make sure that the region remains 

in attainment for the current fine particle standards (annual: 12 μg/m3, daily: 35 μg/m3). EPA is 

also planning to propose a possibly tougher ozone standard this year. EPA may also further 

tighten the fine particle standard in the future. 

In view of the challenges ahead for meeting and/or maintaining the tougher federal ozone and 

fine particle standards, the Washington region needs to reduce the emissions of pollutants 

producing ozone and fine particles (VOC, NOx, PM2.5, and SO2) significantly. The Tier 3 rule 

will help the Washington region immensely as it will provide cleaner gasoline and vehicles. This 

will also help the three jurisdictions in this region as they implement strategies to meet and/or 

maintain the above mentioned federal standards.

Passenger vehicles are the largest emitters of nitrogen oxides (NOx) and one of the largest 

emitters of volatile organic compounds (VOCs), carbon monoxide (CO), and PM2.5 in the 

Washington region. A study by the National Association of Clean Air Agencies (NACAA) 

estimated that the Tier 3 program can reduce gasoline vehicle emissions of nitrogen oxides, 

carbon monoxide, and volatile organic compounds by 29, 38 and 26 percent respectively.

Reductions in emissions of the above pollutants will cause reduction in the levels of ozone, fine 

particles, and carbon monoxide. Clearly, implementation of the Tier 3 rule will lead to 

significantly cleaner air in the Washington region, providing important health benefits to 

millions of people.
Chapter 3: Emissions and Air Quality Emissions Impacts

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Commenter: Mid-Atlantic Regional Air Management Association Inc. (MARAMA)

Northeast States for Coordinated Air Use Management released their Assessment of Clean 

Gasoline in the Northeast and Mid-Atlantic States. 

Over the first decade of the 21st century. the Mid-Atlantic region achieved significant 

improvements in air quality. Ozone remains a major challenge, and motor vehicles are a major 

source of air pollution in our region. We encourage actions to cost-effectively reduce air 

pollution from motor vehicles as soon as reasonable, enabling the public to breathe healthy air. 

In the absence of a national Tier 3 program, areas needing additional emission reductions may 

have no choice but to turn to other, more expensive, less cost-effective measures, including 

additional controls on stationary sources (including already controlled sources) to meet their 

statutory clean air obligations. This would place an unfair economic burden on local industries 

and businesses when a more cost-effective national program which directly affects the 

contributing sources is available. Moreover, achieving equivalent emission reductions of the 

magnitude that will result from Tier 3 could be extremely difficult, if not impossible, in areas 

where stationary sources are already highly controlled and there aren’t enough other sources to 

implement controls. 

Commenter: National Association of Clean Air Agencies (NACAA)

State and local air pollution control agencies are relying on EPA to adopt the Tier 3 rule. Section 

177 of the Clean Air Act authorizes states to opt into California’s LEV III tailpipe standards, but 

not all states are able to take advantage of this opportunity. Moreover, the Clean Air Act 

precludes all states except California from adopting low-sulfur gasoline standards. Therefore, it 

is imperative that the federal government take action this year to adopt Tier 3. If the rule is not 

promulgated by December 31, 2013, Tier 3 may not apply to the 2017 model year of vehicles 

and an entire year of benefits will be lost. This delay will have a serious and adverse impact on 

human health and welfare. 

Commenter: Natural Resources Defense Council (NRDC)

In the proposed rulemaking, EPA notes that over 158 million people, or half of the U.S. 

population, live in areas that fail to meet one or more National Ambient Air Quality Standards 

(NAAQS). Emissions from motor vehicles are a particularly important contributor to NAAQS 

non-attainment. EPA projects that by 2014 “in many nonattainment areas, cars and light trucks 

will contribute 30–45 percent of total nitrogen oxides (NOX) emissions, 20–25 percent of total 

volatile organic compound (VOC) emissions, and 5–10 percent of total direct particulate matter 

(PM2.5) emissions”. By reducing these compounds through the Tier 3 rules, meaningful and 

necessary reductions in ozone, PM and other air pollution can be achieved. EPA projects that the 

Tier 3 proposal will bring many counties from above to below the ozone NAAQS.

Commenter: Northeast States for Coordinated Air Use Management (NESCAUM)

Even with the projected benefits associated with programs currently in effect, many of our most 

populous areas are predicted to be nonattainment for the current 0.075 ppm ozone NAAQS in 
Tier 3 Summary and Analysis of Comments

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2015. Current nonattainment designations of the ozone NAAQS fail to capture the extent of the 

ozone pollution problem in the eastern United States. When EPA determined the attainment 

status of areas in the U.S., it based its determinations on ozone monitoring data collected during 

either 2008-2010 or 2009-2011. In the eastern states (Texas to North Dakota and to the east), 

there were 99 monitors measuring ozone levels in violation of the 0.075 ppm NAAQS during 

these years. This, however, presents a misleading picture of the extent of the air pollution 

problem facing the states. In contrast to the time periods used by EPA to designate ozone 

nonattainment areas, during 2010-2012 there were 252 monitors measuring violations of the 

ozone NAAQS in these same states, an increase of over 150% in the number of violating 

monitors. Many of these monitors are in cities, towns, and counties that EPA did not originally 

identify as having ozone pollution problems.

Attaining the standard in these areas will require additional NOx reductions within our region as 

well as in upwind areas that contribute to the region’s pollution burden. Tier 3 is the most 

significant strategy that the federal government could implement to help states attain and 

maintain the NAAQS for ozone. The combined near-term benefits of the low sulfur gasoline 

provisions and the increasing benefits of the tailpipe standards would help areas that need 

additional reductions to attain, and assist other areas to stay in attainment.

The NESCAUM region, home to over 42 million people, is subject to episodes of poor air 

quality resulting from ground-level ozone and fine particle pollution. During severe events, the 

scale of the problem can extend beyond NESCAUM’s borders and include over 200,000 square 

miles across the eastern United States. Local and regional sources as well as air pollution 

transported hundreds of miles from distant sources outside the region contribute to elevated 

ozone and fine particle concentrations in the region.

NOx emissions contribute to a number of adverse public health and environmental outcomes. 

NOx is the most important contributor to regional ozone concentrations and an important 

precursor to fine particulate matter formation. These two pollutants are responsible for tens of 

thousands of premature deaths, hospital admissions, and lost work and school days in the U.S. 

annually. NOx is also a key factor in a number of environmental problems that affect the 

Northeast.

Ozone remains a persistent pollution problem in parts of the NESCAUM region during warm 

weather months. The evolution of severe ozone episodes often begins with the passage of a large 

high pressure area from the Midwest to the middle or southern Atlantic states. Three primary 

pollution transport pathways affect air quality in the region: long-range, mid-level, and nearsurface. During severe ozone episodes associated with high-pressure systems, these pathways 

converge on the Mid-Atlantic area, where sea and bay breezes act as a barrier and funnel ozone 

and other air pollutants up the Northeast Corridor.

Collectively, NOx emissions and ambient ozone concentrations in the region have dropped 

significantly since 1997, along with the frequency and magnitude of exceedances of the healthbased ozone NAAQS. Despite this demonstrated progress, many of the most populous areas of 

the region continue to violate the current 0.075 ppm ozone NAAQS. Attaining the standard in 

these areas will require significant additional NOx reductions within the Northeast and in upwind 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-50

areas. Federal measures such as the Tier 3/low sulfur gasoline program will significantly reduce 

NOx emissions and help states achieve the requisite reductions.

Looking toward the future, additional NOx reductions will be critical to ozone attainment in a 

broader swath of the region if EPA were to adopt a more health protective ozone NAAQS in the 

range of 0.060 – 0.070 ppm as recommended by EPA’s Clean Air Scientific Advisory 

Committee (CASAC).

Commenter: Sierra Club

Further, the proposed rule will improve air quality across the country, especially those regions in 

non-attainment with the health-based National Ambient Air Quality Standards (“NAAQS”). As 

the RIA demonstrates, without Tier 3, several counties will continue to violate the 8-hour ozone 

standard. Specifically, without the benefits of the Tier 3 controls, in 2017, 40 counties, with a 

projected population of almost 50 million people, would experience levels of ozone that exceed 

the 2008 8-hour ozone standard of 75 ppb. Tier 3 will assist those areas with attainment in 2017 

and beyond, including some counties that would reduce ozone design values from above the 

level of the standard to below it as a result of pollution reductions achieved solely by the 

proposed rule. Moreover, the benefits of reduced ozone resulting from the proposed rule will 

help fill the regulatory gap created by EPA’s overdue review of the 2008 ozone standards.

Similarly, the proposed Tier 3 standard will assist many regions of the country that are currently 

designated nonattainment for PM2.5 to come into compliance with the NAAQS. At present, 

there are 50 PM2.5 nonattainment areas (for the 2006 NAAQS) with a population totaling over 

105 million people. EPA provides evidence that 24-hour PM2.5 will decrease for many counties 

by 2030 as a result of the proposed rule’s projected emissions reductions of PM2.5, NOx SOx, 

and VOCs.

The proposed rule also will decrease ambient levels of NO2. Reductions in NO2 resulting from 

Tier 3 will “help any potential nonattainment areas to attain and maintain the standard,” thereby 

facilitating compliance with the health-based NAAQS. Moreover, reductions in NO2 will be 

greatest in urban areas, helping to prevent the adverse health effects of NO2 exposure. 

Commenter: State of Utah

Utah currently has three non-attainment areas for the PM2.5 NAAQS. In those areas, Nitrogen 

Oxides (NOx) and Volatile Organic Compounds (VOCs) from on-road mobile sources are a 

primary contributor to the PM2.5 in our air. Preempted by federal statute, Utah is unable to set its 

own vehicle emission standards. The proposed Tier 3 Program, therefore, presents a promising 

strategy to reduce NOx, VOCs, and direct PM2.5 from on-road mobile sources. If EPA’s 

projections are accurate, the proposed Tier 3 Program, in conjunction with new mileage 

efficiency standards for vehicles, will reduce combined NO, and non-methane organic gas 

emissions by 80 percent on a fleet average basis and particulate emissions by 70 percent on a 

per-vehicle basis by the year 2030.

Commenter: Utah Air Quality Board
Tier 3 Summary and Analysis of Comments

3-51

Utah faces recurrent episodic air quality challenges for ozone and PM2.5. The state currently has 

three non-attainment areas for the PM2.5 NAAQS. In those areas, on-road mobile sources are 

currently one of the largest source categories for emissions of NOx and Volatile Organic 

Compounds (VOCs). However, by federal statute, the state is preempted from setting vehicle 

emission standards, leaving us with limited options for reducing on-road mobile source 

emissions. The proposed Tier 3 Program fills this gap by providing a means of greatly reducing 

NOx, VOCs, and direct from onroad mobile sources. Specifically, the proposed Tier 3 Program 

will reduce combined NOx and nonmethane organic gas (NMOG, a subset of VOC) emission 

standards by 80 percent on a fleet average basis and particulate emission standards by 70 percent 

on a per-vehicle basis. 

Commenter: Respiratory Health Association (RHA)

Anyone who has trouble breathing or has limited lung capacity will benefit from cleaner, less 

polluted air. The Tier 3 rule will help achieve the drastic ozone reductions still needed to 

achieve the current inadequate ozone standard. A strong Tier 3 standard will also be extremely 

helpful in meeting an ozone standard based on science that the EPA should establish later this 

year.

As the ozone standard still isn’t correctly set, the reality is that the number is certainly higher 

than the 158 million people EPA says are exposed to unhealthy levels of air pollution. Far too 

many people do not even know that their air is not meeting standards that will protect their 

health.

Commenter: Ozone Transport Commission (OTC)

Motor vehicles are the Ozone Transport Region’s largest source of NOX, which is the most 

important contributor to elevated regional ozone concentrations. EPA’s Tier 3 proposal would 

reduce NOX.

EPA is required under the Clean Air Act to set NAAQS that are protective of human health and 

welfare. EPA lowered the health-based 8-hour ozone NAAQS to 75 parts per billion in 2008 and 

is anticipated to promulgate a more stringent standard in 2014. The OTC’s modeling efforts 

demonstrate that gasoline-powered vehicles remain a significant contributor to ground level 

ozone. Based on this modeling demonstration, attainment of the 2008 health-based ozone 

standard will be impossible in the OTR without additional emission reductions from highway 

vehicles and other mobile sources. Ozone precursor emissions from mobile sources are the 

largest contributor to ozone levels within the OTR. As stated in the Preamble for EPA’s 

proposed rule ‘Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission 

and Fuel Standards,’ the vehicle emission standards, combined with the proposed reduction of 

gasoline sulfur content from the current 30 parts per million (ppm) average down to a 10-ppm 

average, is expected to result in a dramatic emission reduction of NOR, VOC, direct PM2.5, 

carbon monoxide and air toxics. (78 Fed. Reg. 29816). Cleaner vehicles under the Tier 3 

program will significantly reduce ozone precursor emissions and other pollutants as these 

vehicles replace the existing vehicle fleet. Cleaner fuels will have the significant added 

advantage of reducing emissions from the in-use fleet by enabling catalytic converters to reduce 

pollution from all gasoline-powered vehicles by limiting ‘NOR creep’ associated with sulfur 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-52

build up in the catalyst. Without clean gasoline, existing and improved vehicle emission 

standards will not be as effective. 

The Ozone Transport Commission (OTC) member states call on the U.S. Environmental 

Protection Agency (EPA) to significantly reduce pollution from gasoline-powered motor 

vehicles by promulgating stringent vehicle emission standards and lower sulfur content standards 

for gasoline. Adoption of federal ‘Control of Air Pollution from Motor Vehicles: Tier 3 Motor 

Vehicle Emission and Fuel Standards’ as proposed by EPA on March 29, 2013 will reduce ozone 

and ozone precursors in the Northeast and Mid-Atlantic states, as well as in upwind states, that 

significantly contribute to nonattainment of the ozone National Ambient Air Quality Standards 

(NAAQS) in the Ozone Transport Region (OTR). 

Commenter: Maryland Department of Transportation

Many counties in Maryland have been designated nonattainment for ozone and/or particulate 

matter, which concerns us greatly. Maryland has already implemented many stringent controls, 

costly transit improvements, and mobile source emission reduction strategies. However, we need 

more effective programs that provide additional reductions of harmful emissions. We believe 

that the Tier 3 Program is a positive step forward in efforts to reduce emissions from motor 

vehicles and a logical progression of the work initiated in the Tier I Program and enhanced by 

the Tier 2 Program. We strongly support the immediate benefits that will accrue to our region as 

soon as the near term reduction of sulfur in fuels takes place and the longer term benefits that 

will be realized as new technology (Tier 3) vehicles are introduced. 

Commenter: New York State Department of Environmental Conservation

Air pollutant concentrations continue to exceed health-based National Ambient Air Quality 

Standards in much of the United States, including portions of New York. Mobile sources, 

particularly light duty vehicles, are often the dominant emission source for ozone precursors. 

EPA’s analysis suggests that in 2030, on-road mobile source emissions of oxides of nitrogen 

(NOx) and volatile organic compounds (VOCs) will be reduced by 28% and 23% respectively. 

These ozone precursor emission reductions will help reduce the incidence of adverse health 

impacts from cardiovascular and respiratory illnesses and conditions known to be associated with 

exposure to elevated levels of ozone. 

The benefits of reducing average gasoline sulfur content to 10 ppm are not limited to future Tier 

3 and LEV III vehicles. EPA’s emissions modeling suggests that roughly half of the NOx 

reductions associated with full implementation of Tier 3 occurs immediately in 2017 due to 

emission reductions from the existing vehicle fleet, attributable to enhanced operation of existing 

emission control equipment. 

If the reductions associated with Tier 3 are not realized, alternative reductions will be necessary 

across much of the country. There may not be sufficient feasible alternatives, and even if 

feasible, any such alternatives will likely be more expensive and more disruptive. This is the 

lowest hanging fruit remaining on the tree. 
Tier 3 Summary and Analysis of Comments

3-53

The sulfur standards and the vehicle standards they facilitate are vital to providing clean, healthy, 

air to millions of New Yorkers. 

These reductions are critical because there are two nonattainment areas in New York State for 

the 2008 ozone national ambient air quality standard (New York-N. New Jersey-Long Island, 

NY-NJ-CT and Jamestown, NY) that are required pursuant to EPA’s designation to attain by 

December 31, 2015. 

Specifically, the United States Environmental Protection Agency (EPA) designated the New 

York — Northern New Jersey — Long Island, NY-NJ-CT area ‘nonattainment’ of the 2008 

ozone national ambient air quality standard (NAAQS) of 0.075 parts per million (ppm) on May 

21, 2012 with a ‘marginal’ classification. The DEC submitted an official reclassification request 

to the EPA on June 20, 2012. The DEC requested to be reclassified pursuant to Clean Air Act 

(CAA) section 181(a)(4) because the New York —Northern New Jersey — Long Island, NY-NJCT ozone nonattainment area’s design value of 0.084 ppm is within five percent of the 

‘moderate’ classification threshold of 0.085 ppm. In the alternative, the DEC requested a 

‘voluntary’ reclassification to ‘moderate’ pursuant to CAA section 181(b)(3). A voluntary 

reclassification under section 181(b)(3) of the CAA is a non-discretionary EPA action; the 

statute provides that ‘[t]he Administrator shall grant the request of any State to reclassify a 

nonattainment area in that State... to a higher classification.’ EPA, however, has not taken any 

action because it questions its authority to grant a voluntary reclassification of the multi-state 

region without the support of Connecticut and New Jersey. It should be noted that the 

Administrator seemingly has the authority under CAA section 107(d)(3) to revise the designation 

of an area if ‘available information indicates that the designation of any area or portion of an area 

within the State or interstate area should be revised.’ In that regard, monitoring data for 2012 

indicates the New York City metropolitan areas design value of 0.086 ppm is above the threshold 

for a ‘moderate’ classification. DEC screening modeling also predicts non-attaining ozone design 

values of 0.082 ppm in 2015 and 0.076 ppm in 2018. 

Therefore, the reductions associated with the Tier 3 gasoline sulfur control and vehicle emissions

standards, estimated below, will be critical in meeting the emission reduction requirements of a 

moderate nonattainment area. 

EPA provides national emission reductions (from MOVES), but does not break them down by 

state. Using a VMT ratio (4.3%, from data on the FHWA web site (1)) yields an estimate of 

11,000 tons per year NOx in 2017 from the existing fleet and 22,000 tons of NOx in 2030. VOC 

emission reductions are estimated at 1700 tons in 2017 and 9700 tons in 2030. PM2.5 is 5 and 

320 and benzene is 70 and 370 respectively. These additional reductions, on top of what is 

already being achieved, are significant relative to programs that the State has adopted and plans 

to adopt as it deals with ozone nonattainment. NOx reductions in the range of 30 and 60 tons per 

day in 2017 and 2030 respectively, coupled with VOC reductions in the same timeframe of 4.6 

and 26 tons per day would contribute to the State’s continued effort to control ozone precursor 

emissions. 

New York, through its adoption of California’s LEV III vehicle standards, will receive some of 

the emission reductions described above. 
Chapter 3: Emissions and Air Quality Emissions Impacts

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Alternatives are less feasible, more expensive, and more disruptive. 

The air quality impacts of the emissions from motor vehicles can’t be placed in a compartment 

separate from other emission sources. If the necessary emissions reductions from this proposed 

rule are not realized, then they will have to be obtained in some other manner from other sectors 

as the Department develops State Implementation Plans to address nonattainment issues within 

the state. 

Each year the Department works to identify strategies that result in meaningful State 

Implementation Plan reductions. While these efforts have identified areas for significant 

reduction in the past (NOx RACT, NOx SIP Call, Consumer Products, AIM Coatings, etc.) work 

continues on identifying what, if any, additional reductions are available from these program 

categories. If the reductions from Tier 3 are not realized, the Department is concerned that there 

are not enough source categories left to regulate to make up the difference. 

And just to point out that metropolitan New York is in non-attainment for the 2008 ozone 

standard, and we have, in fact, based on actual monitored data requested a bump up of that nonattainment status to moderate.

Well, again, Tier 3 for New York by itself – Tier 3 by itself doesn’t do all that much for us 

because we have the California program, and, in fact, New Jersey has the California program as 

well. But we will certainly see the transport benefits associated with it as we get improvement in 

air quality upwind from Tier 3.

Our issues are we’re – we are non-attainment based on current monitoring data, based on 2012 

data. We’re still non-attainment. In fact, 2012 made us worse because it got rid of a cool 

summer. So when we look at our current non-attainment status and the fact that we’ve requested 

a bump up to moderate. We need to get the reductions to get into attainment in the 2018 time 

frame, which would be required. 2015 looks virtually impossible.

While the emissions benefits associated with the Tier 3 standards won’t fully accrue until the 

fleet turnover, the environmental benefits from gasoline sulfur reductions will also improve the 

effectiveness of millions of catalytic converters already in the field. We know that some of the 

effects of sulfur on catalysts is reversible, so as soon as it goes into effect, we get benefits. Your 

documents suggest 284,000 tons of NOx nationally in 2017. That’s probably in the order of 

10,000 tons of NOx for New York.

And to illustrate some of that impact, I looked at data – I/M data for 2012 in New York, and we 

had 17,000 vehicles fail initial I/M tests for catalytic converter. And we don’t know how many 

might’ve been repaired before they were tested, so we know that sulfur improvements would 

reduce that catalyst impact, and, therefore, not only save some money for the owners for catalyst 

repairs, but also give us environmental benefits.

The real big bite occurs with the fuel sulfur benefit that allows us to get immediate improvement 

and, you know, just doing a little pro rata of EPA’s numbers, it looks like 10,000 tons of NOx for 

New York. So, yeah, we can use that.
Tier 3 Summary and Analysis of Comments

3-55

Commenter: American Lung Association

On March 29, 2013, EPA proposed an implementation rule for the 2008 ozone National 

Ambient Air Quality Standards (NAAQS). EPA assumed a Tier 3 program with strong low 

sulfur gasoline standards in its baseline analysis for attainment of the ozone NAAQS adopted in 

2008. State and local governments are also preparing to meet NAAQS for particulate matter, 

nitrogen dioxide, and sulfur dioxide. Tier 3 will be a critical tool for local and state governments 

to meet these clean air goals. In absence of Federal Tier 3 standards, state and local governments 

will have to turn to other measures. In most areas, mobile sources comprise a large percentage of 

the emission inventory across the nation. Finding pollution reductions equal to those that would 

have come from a Federal Tier 3 program will be difficult.

Commenter: Environmental Defense Fund (EDF)

Tier 3 will make significant and immediate progress to reduce the pollution that forms harmful 

ozone. The emission reductions made under this program are a crucial piece of what must be a 

multipronged strategy to reduce ozone. Tier 3 will help states meet the 2008 Ozone NAAQS and 

prepare to meet the expected 2013 Ozone NAAQS.

Our Response:

Chapter 7 of the RIA and Section III of the preamble to the final rule include EPA 

projections of emission reductions and air quality improvements from the Tier 3 standards. EPA 

believes that the emissions reductions and air quality improvements from the Tier 3 standards 

will help states to attain and maintain the NAAQS “as expeditiously as practicable.” (Sections 

172(a)(2) and 181 of the CAA). The Tier 3 emissions reductions and air quality improvements 

occur in a timeframe that is relevant for 2008 ozone nonattainment areas classified as moderate, 

serious, severe and extreme. By beginning the program in 2017, it will aid attainment of the 

NAAQS in moderate areas by December 2018. Furthermore, the Tier 3 standards will help any 

areas that attain the NAAQS (including current marginal nonattainment areas) to maintain that 

NAAQS in the future. EPA received numerous comments from states and other groups 

indicating that the emission reductions and air quality improvements need to occur as soon as 

possible. Timely implementation of Tier 3 will both provide public health benefits as soon as 

possible, and also assist states as they develop attainment and maintenance plans (to avoid the 

need for other, more costly state/local measures).

3.2.2. Air Quality Impacts of the Tier 3 Standards are Negligible

Three commenters, API, AFPM and Marathon, reference two studies done by Environ to assert 

that the air quality benefits of the Tier 3 rule are negligible.20,21 Another commenter, EDF, noted 

 

20 ENVIRON, Effects of Light-duty Vehicle Emissions Standards and Gasoline Sulfur Level on Ambient Ozone, 

Final Report, prepared for the American Petroleum Institute, September 2012

21 ENVIRON, Effects of Light-duty Vehicle Emissions Standards and Gasoline Sulfur Level on Ambient Fine 

Particulate Matter, Draft Final Report, prepared for the American Petroleum Institute, June 2013 
Chapter 3: Emissions and Air Quality Emissions Impacts

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that the Environ studies underestimate the benefits of the Tier 3 program because they analyze 

2022, which is an interim year when the benefits of Tier 3 are not fully realized. Another 

commenter, ECTA, hired Navigant Economics to compare the Environ studies and the EPA 

analysis of Tier 3 impacts and concluded that the results, although not directly comparable, are 

largely consistent and that the projected incremental benefits of Tier 3 vastly exceed the 

incremental costs. Another commenter, Alliance and Global, noted that both the June 2013 

Environ study and a 2013 Bloomberg Government (“BGOV”) “Regulatory Analysis of EPA’s 

Tier 3 rule” focus on one co-benefit of sulfur reduction without addressing the totality of other 

co-benefits.

What Commenters Said: 

Commenter: American Fuel & Petrochemical Manufacturers (AFPM); American Petroleum 

Institute (API); Marathon Petroleum Company LP (MPC)

Emissions benefits of the Tier 2 program continue to be realized as the vehicle fleet turns over. 

In modeling the environmental impacts out to year 2022, recent studies by ENVIRON showed 

that Tier 3 would yield incremental reductions in mean monthly summer 2022 PM2.5 

concentrations of no more than 0.1 μg/m3 in contrast to a maximum incremental reduction of 2.7 

μg/m3 in mean monthly PM2.5 ambient levels under the federal Tier 2 program. Similarly for 

ozone, ENVIRON found the maximum ozone benefit expected from Tier 3 to be less than 1 ppb, 

relative to a maximum ozone benefit of 12 ppb anticipated from the federal Tier 2 program. 

EPA’s modeling calculates Tier 3 reductions in ozone of 0.5 - 1.35 ppb and in PM2.5 of 0 - 0.05 

μg/m3 in years 2017 - 2030. It should be mentioned that the current ozone and PM2.5 NAAQS 

are 75 ppb and 12 μg/m3, respectively. The ENVIRON studies support the conclusion that 

EPA’s Tier 3 standards for new vehicle emissions and gasoline sulfur will provide negligible 

reductions in emissions inventories, and negligible improvements in air quality. 

Negligible environmental benefits: 

The emissions inventory and air quality impacts of the Tier 3 Proposal are negligible. Even if 

one accepts an assertion that EPA’s air quality modeling analysis is accurately assessing the 

impacts of the emissions reductions claimed for the Tier 3 proposal, these are likely to be 

negligible. As the data analysis below shows, the proposed Tier 3 standards for new vehicle 

emissions and gasoline sulfur will provide negligible environmental benefit, with respect to both 

(a) reductions in emissions inventories, and (b) improvements in air quality. API recently 

sponsored an assessment of the incremental nationwide emissions inventory reductions and air 

quality benefits associated with the adoption of progressively more stringent light duty vehicle 

emissions standards and gasoline sulfur limits over time (11). The studies, conducted by 

ENVIRON, (12) (13) and provided as Attachments No. 9 and No. 10, showed that in 2022, the 

summertime ozone precursor emissions of volatile organic compounds (VOCs), oxides of 

nitrogen (NOx), and carbon monoxide (CO) from gasoline-fueled light-duty vehicles are 

projected to be reduced by 62%, 80% and 51% respectively as a result of the implementation of 

the federal Tier 2 program. In contrast, implementation of a federal Tier 3 program would further 

reduce VOC, NOx and CO emissions by only 8%, 11% and 7%, respectively. Similarly, Tier 3 is 

expected to yield lower reductions in PM precursors in comparison to those achieved by the Tier 
Tier 3 Summary and Analysis of Comments

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2 program. The study showed incremental reductions in SO2 and direct PM2.5 of 92% and 19%, 

respectively, attributable to the adoption of Tier 2, compared with additional reductions in SO2 

and direct PM2.5 of 64% and 5%, respectively, as a result of Tier 3. It should be noted that the 

absolute level of SO2 emissions in Tier 2 and 3 is two orders of magnitude lower than NOx 

levels (e.g., 48.4 vs. 2879 Mg/day) and thus a 64% improvement of a very small number is 

insignificant.

Following the trend in emissions inventories, ENVIRON found that Tier 3 is expected to yield 

negligible improvement in ambient ozone levels relative to the large reductions that have 

occurred (and are expected to continue) as a result of Tier 2. The maximum ozone benefit 

expected from Tier 3 is less than 1 ppb, relative to a maximum ozone benefit of 12 ppb 

anticipated from the federal Tier 2 program.

Similarly, ENVIRON concluded that incremental reductions in the monthly mean of ambient 

PM2.5 concentrations attributable to Tier 3 will be negligible in comparison to those expected 

from Tier 2. The study showed that Tier 3 would yield incremental reductions in mean monthly 

summer 2022 PM2.5 concentrations of no more than 0.1 μg/m3 in contrast to a maximum 

incremental reduction of 2.7 μg/m3 in mean monthly PM2.5 ambient levels under the federal 

Tier 2 program. 

Commenter: Emissions Control Technology Association (ECTA)

Most recently, on June 6, 2013, the American Petroleum Institute (API) released a study 

prepared by ENVIRON International Corporation which concluded that relative to Tier 2, Tier 3 

would only deliver small benefits in terms of PM2.5 reduction. The implication is that Tier 3 is 

not justified because it will deliver small marginal environmental benefits. We strongly disagree 

with this conclusion. 

At ECTA’s request, Dr. Hal Singer of Navigant Economics performed a review of ENVIRON’s 

study to assess its creditability. Dr. Singer compared the ENVIRON analysis with EPA’s 

analysis presented in the proposed rule and concluded that the results are largely consistent. He 

also concluded that the point estimate of 2022 used in the ENVIRON study is misleading 

because it does not reflect the full environmental benefit of PM2.5 reductions achieved under the 

rule. Only a portion of the fleet will be upgraded to tighter Tier 3 standards by 2022. EPA’s 

analysis shows that a significant environmental benefit from Tier 3, in terms of PM2.5 

reductions, will not be achieved until 2030 when 80% of the light-duty fleet is Tier 3 compliant. 

ENVIRON was silent on the projected benefits from Tier 3 in 2030. 

At your request, I have reviewed ENVIRON’s study of the projected benefits from Tier 3, and I 

compared its major results against those of the EPA. ENVIRON estimates that relative to 

emissions reduction attributable to Tier 2, by 2022Tier 3 would reduce emissions from PM2.5 by 

only 3 percent, and would reduce the monthly mean 24-hour PM2.5 concentrations in the Eastern 

portion of the United States by less than 0.1 micrograms per cubic meter (μg/m3). Because these 

incremental reductions in PM2.5 are relatively smaller than the reductions achieved by Tier 2, 

the ENVIRON study gives the impression that Tier 3 might not be justified. 
Chapter 3: Emissions and Air Quality Emissions Impacts

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To survive a cost-benefit test, however, there is no reason why Tier 3 must deliver the same 

benefits as Tier 2; rather, Tier 3 need only deliver incremental benefits in excess of incremental 

costs. EPA’s analysis shows that the proposed benefits of Tier 3 by 2030 would exceed the 

proposed costs by between $4 and $20 billion. Thus, opponents of Tier 3 need to show that 

EPA’s benefits by 2030 are overstated by between $4 and $20 billion. Yet the ENVIRON study 

is silent about the projected benefits from Tier 3 in 2030. 

Moreover, the ENVIRON study does not even imply that Tier 3-related benefits by 2030 would 

be significantly less than EPA’s estimated benefits. As demonstrated below, there appears to be 

no material difference in the projected incremental benefits of Tier 3 (relative to Tier 2) between 

the ENVIRON study and the EPA study. Because ENVIRON’s estimated reductions by 2022 

are larger than those of EPA by 2017 but smaller than those of EPA by 2030 (with the exception 

of NOx), it is conceivable that the implied social benefits from the ENVIRON study in 2030 

exceed those of EPA. 

For whatever reasons, the ENVIRON study focused on environmental benefits achieved by 

2022, just five years after the implementation of the proposed rules in 2017. As EPA correctly 

explained, however, it is mistake to look for PM2.5-related benefits before Tier 3-compliant 

vehicles represents a majority of the fleet: “Reductions in direct emissions of PM2.5are projected 

to result solely from the proposed vehicle tailpipe standards, so meaningful reductions are 

realized mainly as the fleet turns over”. Indeed, the ENVIRON study expressly allows for the 

possibility of further reductions in PM2.5 after 2022, yielding larger social benefits: “The main 

limitation of this study is introduced by the lack of complete phase-in of the LEV III standard by 

2022, the basis year for comparing emission standards. Some additional improvements in PM2.5 

beyond 2022 are expected as the LEV III standard fully matures”. By providing benefits for 2022 

only, the ENVIRON study makes it difficult to compare its results with those of EPA, which 

presented benefits in 2017 (the first year of implementation) and in 2030 (when 80 percent of the 

light-duty fleet are Tier 3-compliant).

With this caveat in mind, it is possible to compare the projected benefits across the two studies. 

The ENVIRON study estimates incremental benefits by 2022 with partial LEV III technology 

penetration of 8%, 7%, 11%, 64% and 5% in VOC, CO, NOx, SO2, and PM2.5 emissions, 

respectively, from CONUS emissions of light-duty vehicles. The projected reductions in 

emissions decline to 6%, 7%, 5%, 50%, and 3% in VOC, CO, NOx, SO2, and PM2.5, 

respectively, when expressed as a share of emissions from all “on-road vehicles”. By 

comparison, the EPA projects reductions by 2017 of 3%, 4%, 8%, 51%, and 0.1% in VOC, CO, 

NOx, SO2, and PM2.5 emissions, respectively; by 2030, EPA projects reductions of 23%, 30%, 

28%, 51% and 10% in VOC, CO, NOx, SO2, and PM2.5 emissions, respectively.

Accordingly, ENVIRON’s projected 3% decline in PM2.5 emissions by 2022 is consistent with 

EPA’s estimates of 0.1% decline by 2017 and 10% decline by 2030.The same is true of 

ENVIRON’s projected declines in VOC and CO emissions, which also are larger than EPA’s 

estimates for 2017 but smaller than EPA’s estimates for 2030. There is effectively no difference 

in the two estimates for SO2. Accordingly, the only so-called inconsistency across the two 

studies is for NOx; but even here the projected differences are small (5% for ENVIRON in 2022 

versus 8% for EPA in 2017). 
Tier 3 Summary and Analysis of Comments

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In summary, unless and until ENVIRON produces emission-reduction estimates for 2030 

attributable to Tier 3, it is difficult to compare the projections of the two models. As the record 

currently stands, the two models are largely consistent, and the projected incremental benefits of 

Tier 3 still vastly exceed the incremental costs. 

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

In the past few weeks, two analyses have been published that critique EPA’s Proposed Tier 3 and 

Proposed Gasoline Sulfur Standards. Both of these analyses are flawed because they “cherry 

pick” one co-benefit of sulfur reduction and over-focus on it, without addressing the totality of 

other co-benefits. 

Automaker Response to ENVIRON Modeling Study on EPA Tier 3 Impact on PM2.5 Air 

Quality – On June 20, 2013, API announced a new modeling study by ENVIRON International 

Corporation which concludes that pending EPA Tier 3 regulations, including the proposed 

reduction of one part of the current EPA market gasoline sulfur standard (the “refinery annual 

average” limit) from 30 to 10 ppm, would do little to reduce fine particulates (PM2.5) by 2022, 

at least in summertime in the U.S. eastern states: 

“Overall, the modeling results suggest that large improvements in summertime ambient groundlevel PM2.5 concentrations occur in the eastern US as a result of the switch from Tier 1 to Tier 2 

standards. However, relatively small additional reductions in 2022 PM2.5 concentrations are 

predicted to result from the transition to a Federal standard similar to the California LEV III 

standard, even when considering emissions reductions due to a lower gasoline sulfur content in 

the LEV III scenario. These results are due to one or both of the following factors depending on 

the pollutant: (1) the change in emissions between the Tier 2 and LEV III scenarios is relatively 

small compared to the change between the Tier 1 and Tier 2 scenarios, and (2) the Tier 2 LDV 

emissions of PM2.5 precursors constitute a relatively small fraction of the total inventory. In 

particular, in the case of the PM2.5 precursor that experiences the largest relative reduction from 

the Tier 2 to LEV III scenarios, SO2, on-road LDV emissions constitute only 0.2% of the total 

anthropogenic inventory and hence SO2 LDV emission reductions result in small ambient PM2.5 

benefits.

The main limitation of this study is introduced by the lack of complete phase-in of the LEV III 

standard by 2022, the basis year for comparing emission standards. Some additional 

improvements in PM 2.5 beyond 2022 are expected as the LEV III standard fully matures. In 

addition, this study does not address wintertime PM2.5 benefits.”

(Emphasis added), Sec. 3.2, p. 19, ENVIRON, “Effects of Light-duty Vehicle Emissions 

Standards and Gasoline Sulfur Level on Ambient fine Particulate Matter,” Final Report Prepared 

for the American Petroleum Institute , June 2013, Project No. 06-31891A. 

ENVIRON’s Conclusion Fails to Address Full Co-benefits of Tier 3 and Reduced Gasoline 

Sulfur: In addition to the very important limitations of the ENVIRON study acknowledged at the 

end of the report’s conclusion, it is misleading to focus on only one co-benefit of market gasoline 
Chapter 3: Emissions and Air Quality Emissions Impacts

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sulfur reduction (in this case reduction of S02 as a precursor to PM2.5 vehicle emissions) 

without acknowledging the entire suite of significant additional co-benefits resulting from EPA’s 

proposed Tier 3 standard and more stringent market gasoline sulfur standard. These include 

reducing various other vehicle emissions of concern, and enabling more fuel efficient vehicle 

technologies. Use of ENVIRON’s findings requires appropriate additional context. Likewise, 

discussions of regulatory costs must be viewed in terms of the totality of the benefits. 

ENVIRON’s modeling analysis compares the effects of EPA emission standards and reductions 

in market gasoline sulfur on PM2.5 precursor exhaust emissions in Tier 1 vs. Tier 2 standards, 

compared with Tier 2 vs. proposed Tier 3 (represented by California LEV III) scenarios for one 

season and one geographic area. Unfortunately, the conclusion focuses on only one among many 

co-benefits. 

SO2, as one precursor to PM2.5, will in fact increase year round, if the sulfur content of the fuel 

is enough to “poison” the catalyst. Sulfur coats the surface and also chemically impairs the 

catalyst action on the exhaust, preventing it from capturing three other key exhaust emissions, 

NOX (Nitrous Oxides), CO (Carbon Monoxide), and VOCs (Volatile Organic Compounds --

precursors for Ozone and smog formation in the atmosphere) and converting them into nitrogen, 

carbon dioxide and water. Reliable catalytic converter action is critical to meeting tough new 

vehicle tailpipe emission limits. EPA’s own new study data confirm the benefits of reducing 

gasoline sulfur for in use Tier 2 vehicles, even below the new reductions EPA has proposed (See 

EPA Regulatory Impact Analysis, Draft EPA 420-D-13-003). Tier 3 would bring national 

gasoline sulfur closer to California, Japan, and EU levels. 

Finally, the proportion of SO2 as a PM2.5 precursor from vehicle emissions was reduced under 

the study’s modeling scenarios by 92% between Tier 1 and 2, and by 64% between Tier 2 and 3, 

both considerable achievements for air quality across the nation. In any event, under both sets of 

scenarios, the vehicle emission contributions to PM2.5 have always been overshadowed by other 

anthropomorphic sources, so there is nothing really new here from an EPA policy standpoint. In 

addition, when you also consider the cumulative outcome adding ENVIRON’s own Tier 3 

projections of other reductions in vehicle emissions, 11% for NOX, 7% for CO, and 8% for 

VOCs, and 5% for PM2.5 (and only to 2022, not even later years when additional reductions 

would occur) plus the vehicle technology advancements promoted by reduction of gasoline 

sulfur from Tier 3, the error in highlighting just SO2 or PM2.5 outcomes becomes obvious. That 

said, we agree that NAAQS and State Implementation Plans should continue to include 

reductions from stationary sources where the cost/benefit is justified. 

Automaker Response to BGOV Regulatory Analysis of EPA’s Tier 3 Rule: On June 13, 2013, a 

Bloomberg Government (“BGOV”) “Regulatory Analysis of EPA’s Tier 3 rule” © Bloomberg 

2013, Bloomberg Finance LP, was published that, among other things, found “...SO2 reductions 

achieved by Tier 3 will be relatively expensive, with a cost of nearly $76,500 a ton of S02 

reduced” and ends saying “Bloomberg Government’s analysis finds that Tier 3 will have a costly 

but minimal impact on certain pollutants targeted by the rule and that the health benefits are 

possibly overstated based on recent academic research. Also, viewing sulfur independently, 

would yield more cost-effective ways of meeting Tier 3’s proposed requirements.” 
Tier 3 Summary and Analysis of Comments

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As with the ENVIRON report conclusion, you cannot disaggregate one co-benefit of gasoline 

sulfur reduction for analysis (e.g., its reduction of SO2 vehicle emissions) from the entirety of all 

the emission benefits from reducing sulfur in marketplace gasoline. Since you cannot logically 

isolate the benefits for only one component of the exhaust without counting the benefits for the 

other components, it is erroneous to assign the entire annualized cost of the sulfur reduction to 

just one component benefit (i.e., taking $1.3B \17,000 tons of SO2 reduction to reach $76,500) 

which strongly overstates the proportionate cost. The Tier 3 benefits of reducing sulfur would 

not only enable prospective reductions for future vehicles, the reduction in market fuel would 

also reduce emissions in the existing fleet and in other types of engines. 

Commenter: Environmental Defense Fund (EDF)

In addition to overstating the costs of Tier 3, API erroneously claims that Tier 3 will not generate 

any health benefits. Despite numerous independent, credible analyses, API has said that there 

would be no benefits in reduced ozone or PM2.5 from Tier 3 versus Tier 2. However, their 

ozone and PM assessments, conducted by ENVIRON International Corp., are seriously flawed 

and misleading, and both underestimate the significant benefits of the Tier 3 program. Both 

analyses estimate the benefits for the year 2022, instead of 2030 when the benefits of Tier 3 will 

be more fully realized.

Commenter: National Association of Clean Air Agencies (NACAA)

NACAA strongly supports EPA’s Tier 3 proposal to further strengthen the federal program to 

regulate emissions from passenger cars and light trucks and lower sulfur levels in gasoline. We 

are so supportive because we know of no other strategy that can achieve such substantial, 

immediate and cost-effective reductions in air pollution as Tier 3.

Our Response:

The air quality impacts predicted to result from the Tier 3 rule are significant. As 

NACAA pointed out, these air quality improvements are greater than could be achieved by any 

other known, practical measure in the same timeframe. As described in Chapter 8 of the RIA, 

these air quality improvements will provide the public with very significant health benefits and 

the benefits of the final standards clearly outweigh the costs. In addition, as pointed out by the 

Alliance and Global, the benefits of the rule come from the entire suite of emissions reductions 

due to reducing sulfur in fuel, not just the reduction in SO2 from on-road vehicles. 

3.2.3. Inadequate Technical Justification - Air Quality Impacts

What Commenters Said: 

Commenter: American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum 

Institute (API) and Marathon Petroleum Company LP (MPC)
Chapter 3: Emissions and Air Quality Emissions Impacts

3-62

API and AFPM submitted a report from Sierra Research in support for their comments.22 The 

Sierra report included two comments on Air Quality Impacts (see Section 7 of Sierra report). 

The first comment pertains to EPA’s model performance evaluation and the second comment 

pertains to the grid size for EPA’s air quality analysis.

Based on the data presented by EPA, the agency’s evaluation of model performance shows 

that the model generated acceptable predictions of overall ozone and PM concentrations. 

However, EPA failed to evaluate how well the model predicts VOC to NOx ratios or model 

responsiveness to reductions in VOC, NOx, and/or PM emissions. This is an important issue 

because uncertainty and compensating errors in the emission inventories and other inputs to 

the air quality model make it possible for model performance in predicting ozone and PM 

concentrations to be acceptable even if the model cannot accurately predict responses to 

emission reductions. Given that the point of the modeling analysis is to assess the air quality 

impacts of the emission reductions estimated to result from the Tier 3 proposal, EPA’s failure 

to perform this evaluation is a major flaw.

That there are large uncertainties in projected mobile source emission inventories is 

highlighted by the large changes in those inventories whenever emission modeling software is 

updated. Most recently, the release of the MOVES model increased motor vehicle emissions 

considerably and altered VOC/NOx emission ratios. Uncertainty in emissions and in model 

response to emission reductions is largest in urban areas where motor vehicle emissions are 

concentrated, so the ability of the Tier 3 modeling to adequately respond to Tier 3 emission 

reductions is also very uncertain in the absence of a meaningful evaluation of this issue by 

EPA. In addition to failing to evaluate the performance of the model in response to changes in 

emissions, EPA also failed to assess the role and relative importance of NOx or VOC 

emission reductions in reducing ambient ozone concentrations or the role of PM, VOC, and 

NOx emission reductions in reducing ambient concentrations of PM2.5. As is well known, 

depending on the VOC/NOx ratio, NOx emission reductions can either increase or decrease 

ambient ozone concentrations. In addition, NOx emission reductions can significantly impact 

PM2.5 formation. In the absence of any assessment of the role and importance of NOx 

emission reductions, it is impossible to determine the air quality benefits of the Tier 3 

proposal in general and the proposed reductions in gasoline sulfur levels in particular.

The motor vehicle NOx emissions targeted by the Tier 3 proposal are concentrated in urban 

centers where NOx reductions are less effective in reducing ozone; therefore, understanding 

the model’s response to NOx is particularly important for this rulemaking. An example of how 

the complicated relationship between NOx and ozone, ozone trends, and sensitivity to 

hydrocarbon emission control could have been evaluated by EPA can be seen in an evaluation 

conducted in Atlanta, Georgia. That analysis found a local source of ozone produced by the 

Atlanta urban area superimposed on an elevated regional background. Effects of NOx 

reductions were complicated and dependent on meteorology and location. NOx control was 

judged effective in reducing the regional background, but VOC control was more effective in 

controlling ozone produced locally in the urban plume. Again, EPA’s failure to assess this 

issue makes it impossible to determine the air quality benefits of the Tier 3 proposal. 

 

22 Sierra Research, June 2013/. Assessment of the Emission Benefits of U.S. EPA’s Proposed Tier 3 Motor Vehicle 

Emissions and Fuel Standards. Prepared for: American Petroleum Institute.
Tier 3 Summary and Analysis of Comments

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Another approach to evaluating the performance of the model in responding to changes in 

emissions is to focus on the variation of emissions from weekdays to weekends, which 

provides a real-world test of emission inventories and modeling. Emissions of ozone 

precursors are lower on weekends, primarily due to changes in the patterns of motor vehicle 

use. Observations of weekend and weekday ozone provide very relevant real-world data with 

which to evaluate the impact of motor vehicle emissions on air quality, yet the Tier 3 RIA 

does not even include any discussion of weekend/weekday ozone, much less an assessment.

The potential impact of this approach can be seen in a recent study of Detroit and Atlanta 

motor vehicle emissions with the MOVES model, which found that motor vehicle emissions 

of NOx were 23.7% lower on Saturdays and 49.9% lower on Sundays in compared to 

weekdays, while VOC decreased by 7% on Saturdays and 20% on Sundays. These weekend 

motor vehicle NOx emission reductions are of the same order as those projected by the Tier 3 

regulations. Another recent modeling study of the weekend/weekday phenomena in the 

Midwest found that weekend emissions generally resulted in lower ozone over most of the 

modeling domain, but higher ozone locally in two urban areas, and that NOx reductions on the 

weekend were responsible for the weekend/weekday ozone differences.

Weekend ozone levels have decreased relative to weekday levels recently, and there is now 

little difference in weekend and weekday ozone in most areas of the country as noted in a 

recent study completed by Environ. The study authors note that precursors of ozone have 

decreased significantly and that NOx emission reductions have been larger, leading to an 

increase in VOC/NOx ratios. The faster decline in NOx emissions is a result of regulations 

that targeted the largest stationary NOx sources in the eastern half of the U.S. (acid rain rules, 

NOx SIP call, CAIR rules). Currently, most urban areas have similar ozone on weekends and 

weekdays even though NOx emissions from motor vehicles are much lower on weekends. 

This indicates that mobile source NOx emission reductions do not have a large effect on ozone 

near urban areas, which is a critical issue with respect to the Tier 3 proposal that EPA has 

failed to address.

Our Response: 

The CMAQ model evaluation performed for the Tier 3 rule is consistent with prior 

agency rulemakings, such as the 2017-2025 Light-Duty Vehicle Greenhouse Gas Emission 

Standards Final Rule (77 FR 62624, October 15, 2012). 

There is no independent way to evaluate the impact of VOC and NOx emissions 

sensitivities on CMAQ projections since they cannot be isolated in the real world. However, 

there have been several studies which evaluate the sensitivity of the system as a whole to 

emissions reductions (called dynamic evaluation). Numerous dynamic evaluations of CMAQ’s 

ability to simulate the change in air quality resulting from emissions reductions have been 

conducted and summarized in the peer-reviewed literature. For instance, Napelenok et al (2011) 

concluded that the CMAQ model “is able to reproduce the observed change in daily maximum 8-

hour ozone levels” at the majority of locations when emissions uncertainty is considered. Other 

dynamic evaluations (Zhou et al., 2013, Godowitch et al., 2010, Gilliland et al., 2008, Godowitch 

et al., 2007) have suggested that CMAQ may be a conservative estimate of the air quality 

improvements resulting from emissions reductions. Overall, the ozone, PM2.5, air toxics 
Chapter 3: Emissions and Air Quality Emissions Impacts

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concentrations and nitrate and sulfate deposition model performance results for the 2005 CMAQ 

simulations performed for the Tier 3 proposed rule are within the range or close to that found in 

other recent applications. The model performance results, as described in this report, give us 

confidence that our applications of CMAQ using this 2005 modeling platform provide a 

scientifically credible approach for assessing ozone and PM2.5 concentrations for the purposes 

of the Tier 3 rule.

EPA and other community modeling efforts have long-established that NOx controls are 

the primary mechanism for reducing ozone levels regionally and that VOC reductions can lead to 

more local reductions within specific urban areas (NRC 1991, US EPA 2010, and US EPA 

2013). This finding points to the need for a combined NOx and VOC reduction strategy to 

reduce ozone levels over the U.S. The Tier 3 proposal has been shown by EPA’s fully-evaluated 

modeling analyses to reduce ozone in a significant way over large parts of the U.S.

In addition, the recently released second draft of the ozone Risk and Exposure 

Assessment (available at: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_2008_rea.html) 

evaluated ozone changes that would occur with NOx reductions alone versus what would occur 

with combined NOx and VOC reductions. 

References:

Gilliland, A.B., Hogrefe, C., Pinder, R.W., Godowitch, J.M., Foley, K.L., Rao, S.T. (2008). Dynamic evaluation of 

regional air quality models: assessing changes in O3 stemming from changes in emission and meteorology.

Atmospheric Environment, 42: 5110-5123.

Godowitch, J.M., Pouliot, G.A., Rao, S.T. (2010). Assessing multi-year changes in modeled and observed urban 

NOx concentrations from a dynamic model evaluation perspective. Atmospheric Environment, 44: 2894-2901.

Godowitch, J.M., Hogrefe, C., Rao, S.T. (2008). Diagnostic analysis of a regional air quality model: changes in 

modeled processes affecting ozone and chemical-transport indicators form NOx point source emissions reductions.

Journal of Geophysical Research-Atmospheres, 113(D19): D19303, DOI: 10.1029/2007JD009537.

Napelenok, S.L., Foley, K.M, Kang. D.W., Mathur, R., Pierce, T., Rao, S.T. (2011). Dynamic evaluation of regional 

air quality model’s response to emission reduction in the presence of uncertain emission inventories. Atmospheric 

Environment, 45: 4091-4098.

National Research Council (1991): Rethinking the Ozone Problem in Urban and Regional Air Pollution, National 

Academy Press, Washington D.C., 524pp.

U.S. Environmental Protection Agency (2010): Regulatory Impact Analysis for the Reconsideration of the 2008 

Ozone National Ambient Air Quality Standard, RTP NC, 89pp.

U.S. Environmental Protection Agency (2013): Integrated Science Assessment for Ozone and Related 

Photochemical Oxidants, EPA 600/R-10/076F, RTP NC, 1251pp.

Zhou, W., Cohan, D.S., Napelenok, S.L. (2013). Reconciling NOx emissions reductions and ozone trends in the 

U.S., 2002-2006, Atmospheric Environment, 70: 236-244.

What Commenters Said:

Commenter: American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum 

Institute (API) and Marathon Petroleum Company LP (MPC)

Many studies have shown that ozone formation and sensitivity to NOx control depend on the 

size of the modeling grid. In the Tier 3 NPRM modeling analysis, a uniform 12 km modeling 
Tier 3 Summary and Analysis of Comments

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grid is used to cover the entire United States. The effect of modeling grid size on model 

predictions was not evaluated by EPA.

The 12 km grid is likely to be adequate outside of urban areas and large point sources where 

pollutant gradients are weak. However, the 12 km grid is inadequate to resolve pollutant 

concentrations in urban areas where spatial gradients are large. This leads to an overestimation 

of mixing in urban centers and an underestimation of NOx inhibition effects. Higher grid 

resolution is particularly important for the Tier 3 NPRM because strong motor vehicle 

emission sources—such as major highways and urban centers—are poorly resolved by a 12 

km grid and the benefits of NOx control near motor vehicle emission sources is likely to be 

overestimated. This overestimation will be carried over into the population exposure modeling 

and amplified due to the large population density in the poorly resolved urban areas.

Our Response: 

The use of a 12km grid resolution is appropriate when evaluating regional- to nationalscale emission reduction impacts (http://www.epa.gov/ttn/scram/guidance/guide/final-03-pm-rhguidance.pdf) as was done in the Tier 3 analysis. Use of a 12 km grid resolution is also 

consistent with prior agency rulemakings, such as the NOx SIP Call rulemaking. (63 FR 57356, 

(October 27, 1998).(See also, Michigan v. EPA, 663 F.3d 663 (D.C. Cir., 2000). The credible 

model performance reported in the operation model evaluation

(http://www.epa.gov/otaq/documents/tier3/454r13006.pdf) confirms that 12km resolution 

modeling provides a good representation of the physical and chemical processes important to 

simulating ozone concentrations. Recent work analyzing the accuracy of 12km resolution 2007 

CMAQ simulations compared to equivalent 4km resolution simulations showed no systematic 

improvement in model performance at the finer 4km resolution compared to the 12km resolution 

(Dolwick et al, 2013). An additional study analyzing ozone response to NOx emissions 

reductions at 12km and 4km resolutions (Simon et al, 2013), showed similar regional patterns in 

ozone changes at the two resolutions and also did not show any systematic difference in ozone 

response to NOx cuts at 12 vs. 4 km resolutions when looking across all sites in the Northeastern 

US over the entire 2007 ozone season.

References:

Dolwick, P., Baker, K., Kelly, J., Misenis, C., Phillips, S., Possiel, N., Simon, H., Timin, B. Comparison of CMAQ 

model performance over the Northeast United States as a function of grid resolution (12km vs 4km) for a 2007 

annual model simulation, Community Modeling and Analysis Annual Conference, Chapel Hill, NC, October 2013: 

http://cmascenter.org/conference/2013/agenda.cfm

Simon, H., Baker, K., Possiel, N., Dolwick, P., Timin, B. Model Resolution and Ozone Sensitivity to NOx 

Emissions Changes in the Northeastern US, Community Modeling and Analysis Annual Conference, Chapel Hill, 

NC, October 2013: http://cmascenter.org/conference/2013/agenda.cfm

What Commenters Said: 

Commenter: American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum 

Institute (API) and Marathon Petroleum Company LP (MPC)
Chapter 3: Emissions and Air Quality Emissions Impacts

3-66

API and AFPM submitted a report from Sierra Research in support for their comments.23 The 

Sierra report included the following comment on speciation profiles, see Section 6.3.2 of 

Sierra report, which we’ve addressed here. 

Another area of importance are the speciation profiles for headspace vapors of E0, E10, and 

E15 that were used by EPA in conjunction with the air quality modeling analysis. EPA 

developed new speciation profiles for the Tier 3 analysis

101,102

using headspace measurements 

from a subset of EPAct test program fuels. No attempt was made, however, to determine if

these research fuels are representative of commercial fuels.

The E0, E10, and E15 headspace profiles were each created by averaging headspace 

measurements from two of the EPAct fuels. One fuel in each pair was low in aromatics (15 

vol.% nominal) and the other high (35% vol. nominal). The E10 and E15 headspace profiles 

were also used to create the E15 evaporative emissions profile by taking the ratio of E15/E10 for

each hydrocarbon species and applying the ratio to the existing E10 profile.

Unfortunately, there are differences in the detailed composition of the EPAct fuels that cause

speciation differences that are not related to ethanol content. These differences could create a

bias when comparing air quality impacts of E0, E10, and E15. The distribution of individual

aromatics differs between fuels in an unexpected manner. For instance, the E15 fuel has 

higher benzene and toluene headspace concentrations compared to the E10 fuel, but lower

concentrations of other aromatics like propyl- benzene. It would be preferable to generate the

profiles from composited commercial fuels or to perform a simple correction based on ethanol 

content.

Our Response: 

This rule does not compare air quality impacts of different ethanol blends so this 

comment is beyond the scope of this rule.

3.2.4. Tier 3 Proposal Analysis Overstates the Air Quality Benefits of Reducing Vehicular 

NOx Emissions in Urban Areas

What Commenters Said: 

Commenter: American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum 

Institute (API) and Marathon Petroleum Company LP (MPC)

In the DRIA, EPA did not provide information on how the Tier 3 rule and changes in ozone 

levels may result in a disproportionate impact on populations in urban centers. In their recent 

report on the Benefits and Costs of the Clean Air Act (EPA, 2011), EPA noted that in many 

urban areas, the ozone levels were 15 to 20 ppb higher with the Clean Air Act Amendments 

 

23 Sierra Research, June 2013/. Assessment of the Emission Benefits of U.S. EPA’s Proposed Tier 3 Motor Vehicle 

Emissions and Fuel Standards. Prepared for: American Petroleum Institute.
Tier 3 Summary and Analysis of Comments

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(CAAA) than without. EPA attributed this to NOx scavenging whereby nitrogen oxides, while 

participating as an ozone precursor, can also serve to scavenge or reduce ozone, particularly 

during the peak ozone season and in urban centers where ozone levels might otherwise be quite 

high. Thus, the effect of the CAAA controls was to suppress NOx scavenging in the city centers, 

where “dis-benefits” of the CAAA are the largest. A similar phenomenon may occur when the 

Tier 3 rule is implemented. Since OMB’s guidelines call for regulatory agencies to assess 

distributional effects, EPA’s DRIA is deficient in this area (OMB Circular A-4, page 14).

Our Response:

The CMAQ model used to project changes in ozone from the Tier 3 standards accounts 

for interactions between photochemistry, background concentrations of ozone, VOC and NOX, 

local emissions and meteorology. As described in Chapter 7.2.4.1.1 of the RIA, there is one 

county in 2018 that is projected to have an increase in modeled ozone design value concentration 

(Cuyahoga County, OH, where Cleveland is located). When NOX levels are relatively high and 

VOC levels relatively low, NOX forms inorganic nitrates (i.e., particles) but relatively little 

ozone. In addition, NOx can react directly with ozone resulting in suppressed ozone 

concentrations near NOx emissions sources. Such conditions are called “NOX-saturated.” Under 

these conditions, VOC reductions are effective in reducing ozone, but NOX reductions can 

actually increase local ozone under certain circumstances. We believe that this is the case in 

Cuyahoga County in 2018. In 2030, when the fleet would be composed of vehicles meeting the 

new standards and the NOX and VOC emissions reductions are larger, this ozone disbenefit is 

eliminated, and the design values for all the modeled counties are decreasing.

Our analysis is consistent with OMB and internal guidelines for conducting national-level 

regulatory impact analyses.

3.2.5. Tier 3 Rule will Increase PM2.5 Levels in 10 Nonattainment Counties

What Commenters Said: 

Commenter: Chevron

By 2030, the Tier 3 rulemaking will actually increase PM2.5 levels in 10 nonattainment counties. 

This ‘disbenefit’ effect is due to reductions in reactive precursor species (like NOx) which can 

often result in increases in the secondary pollutants ozone and PM. 

Our Response: 

The increases in PM levels that were reported in the proposed rule were due to a series of 

conservative assumptions and uncertainties related to fuel parameters in 2017, and also an 

emissions processing issue which erroneously increased direct PM emissions in about one third 

of modeled counties, see Chapters 7.2.4.2.3 and 7.1.3.2.2 of the DRIA for the proposed rule. 

EPA noted that we did not believe these increases would actually occur. This was corrected for 

the final rule and as noted in Chapter 7.2.4.2.3 of the RIA, we do not expect that any increases in 

PM2.5 will occur.
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3.2.6. Mobile Source Air Toxics Reductions are Based on Antiquated Data

What Commenters Said: 

Commenter: American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum 

Institute (API) and Marathon Petroleum Company LP (MPC); Truck and 

Engine Manufacturers Association (EMA):

Mobile Source Air Toxics: EPA claims reductions in Mobile Source Air Toxics (MSAT) that are 

based on the use of antiquated databases. In the case of air toxics, EPA makes reference to a

2005 National Air Toxic Assessment (2005 NATA) database. Since EPA issued the Tier 2 

vehicle and fuel standards and the MSAT2 regulations subsequent to releasing the 2005 NATA, 

deriving the proposed Tier 3 mobile source air toxics benefits from the 2005 NATA database 

yields estimates that are highly inflated, not real-world, and seriously suspect. EPA needs to 

develop a current toxics emissions database before it can make any claims about MSAT benefits.

The second error of note is EPA’s allocation of the percentage of outdoor air toxics that can be 

ascribed to mobile sources. EPA cites the 2005 NATA in claiming that mobile sources account 

for “43 percent of outdoor toxic emissions and over 50 percent of the cancer risk and non-cancer 

hazard associated with primary emissions.” (See 78 Fed. Reg. at 29837.) As in the case of EPA’s 

erroneous premise pertaining to UFPs, EPA’s assertion regarding the percentage of air toxics 

associated with mobile sources is premised on outdated and overstated data.

More specifically, in attempting to justify a contemporary rulemaking using 2005 data, EPA is, 

in effect, ignoring the remarkable advancements that have been made in reducing motor vehicle 

emissions, especially heavy-duty vehicle emissions, subsequent to 2005. As evidenced by the 

findings of Phases 1 and 2 of the Advanced Collaborative Emissions Study (ACES), of which 

EPA is a co-funder, emissions of criteria pollutants and air toxics have been reduced across the 

board by up to 99% from new technology diesel engines (“NTDEs”). (See, e.g., Presentation of 

Imad Khalek (SwRI) to the CRC Real World Emissions Workshop, April 2013.) 

Moreover, of the more than 14 million on-road diesel vehicles in operation today, more than 

40% are NTDEs, and more than 60% of the miles driven by diesel vehicles are driven by 

NTDEs. (See, e.g., Presentation of Dan Greenbaum at HEI Annual Conference, April 2013.) 

That remarkable rate of penetration of NTDEs since 2007 (the date of introduction for most 

NTDEs) has had a very significant effect on the aggregate emissions of air toxics that can be 

ascribed to mobile sources. EPA should account for these developments as they significantly 

undercut (as the Agency should have hoped) the premise for the current rulemaking.

Our Response:

Contrary to the commenters’ assertions, the reductions in mobile source air toxics 

estimated to result from the Tier 3 standards are not derived from the 2005 NATA database.

They were modeled for this rule using the MOVES model, taking into account impacts of Tier 2 

vehicle and fuel standards, MSAT2 regulations, and all other mobile source programs currently 
Tier 3 Summary and Analysis of Comments

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in place. See Chapter 7.1.2 of the draft RIA for a list of rules included in the inventory analysis 

for the proposed rule and Memorandum to Docket: Updates to MOVES for the Tier 3 NPRM 

Analysis (March 11, 2013, Docket EPA-HQ-OAR-2011-0135) for information on the air toxics 

updates included in MOVES for the proposed rule. Furthermore, the version of the MOVES 

model used in the Tier 3 analysis relies on emissions data from the ACES program to model 

toxic emissions from 2007 and later diesel engines.

3.2.7. Mobile Source Air Toxics Tables are Confusing

What Commenters Said: 

Commenter: American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum 

Institute (API) and Marathon Petroleum Company LP (MPC)

A table in the Preamble of the proposed Tier 3 rule adds further doubt to EPA’s toxics 

conclusions. Table III-12, titled: “Percent of Total Population Experiencing Changes in Annual 

Ambient concentrations of Toxic Pollutants in 2030....” presents information that is confusing 

and inconsistent. Table III-1 claims a 36% reduction in benzene on road inventories by 2030 but 

the Preamble text associated with table III-12 claims that over 80% of the population will see a 

decrease of at least 2.5% and in fact the 25-50% reduction value for Benzene shows that no 

percent of the population will see this level of reduction. There are similar problems for all of the 

air toxics for which EPA is claiming emission reduction benefits. 

Our Response:

Table III-1 presents reductions in onroad inventories and Table III-12 presents changes in 

ambient concentrations of pollutants. Table III-12 is presenting the percentage of the population 

that is projected to experience various percent changes in ambient concentrations of each of the 

air toxics due to the Tier 3 standards. Adding the rows in the benzene column that are associated 

with a percent change of at least 2.5 % gives an answer of 81%. 

3.2.8. EPA Should Use a Well-to-wheels, Lifecycle Basis for Gasoline and Ethanol Air 

Quality Impacts

What Commenters Said: 

Commenter: American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum 

Institute (API) and Marathon Petroleum Company LP (MPC)

We recommend that EPA uses a well-to-wheels, lifecycle basis for gasoline and ethanol air 

quality impacts. EPA focused only on the vehicle/fuel system (use emissions) and ignored the 

fuel production emissions. According to the National Academy of Sciences (NAS) report 

(“Renewable Fuel Standard: Potential Economic and Environmental Effects of U.S. Biofuel 
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3-70

Policy”, October 2011), ethanol has higher overall emissions than gasoline (see graphs below). 

This is a result of significantly higher production emissions for ethanol arising from production, 

which includes agriculture and the biorefinery. Note the relatively small differences between 

gasoline and ethanol in tailpipe emissions (use). Figure 11 [EPA-HQ-OAR-2011-0135-4276-A2] 

summarizes the NAS report findings. 

As the volume of ethanol increases significantly in EPA’s baseline between 2017 and 2025, EPA 

does not make adjustments to the air quality impact of ethanol emissions. As a result the air 

quality benefits of the proposed Tier 3 rule are overstated.

Our Response:

EPA did use a well-to-wheels approach, and accounted for impacts of increased use of 

ethanol on emissions associated with fuel production and distribution. Details of the approach 

can be found in a memorandum to the docket (Development of Air Quality Reference Case 

Upstream and Portable Fuel Container Inventories for Tier 3 Proposal, Memorandum from Rich 

Cook, December 12, 2012). The commenter also recommends EPA use AEO 2013. EPA is 

using AEO 2013 for its final rule analysis. EPA disagrees with the assertion that it has 

overstated the Tier 3 benefits.

3.2.9. State of Hawaii Should be Exempted from the Standards

What Commenter Said: 

Commenter: Chevron:

Additionally, Tier 3 requirements are not justified by expected air quality improvements in 

certain unique climates like that of Hawaii. We propose that, because the Tier 3 requirements are 

costly and are highly unlikely to have a beneficial impact to the air quality, the state of Hawaii 

should be exempted from the program. 

Our Response:

The Tier 3 rule will reduce emissions of NOx, SOx, PM and VOCs in Hawaii. These 

emission reductions are expected to reduce ambient concentrations of ozone, PM, NOx and SOx 

which will positively impact human health as well as visibility, deposition and ozone-related 

harm to vegetation. Air quality impacts were not able to be modeled in HI due to the size of the 

air quality modeling domain, not because we thought that air quality improvements were 

unlikely.

3.3. Health and Environmental Effects of Criteria and Air Toxics Pollutants

3.3.1. Tailpipe Reductions Will be Offset by Increases in Emissions from Refineries

What Commenters Said: 
Tier 3 Summary and Analysis of Comments

3-71

The commenter is concerned about increases in emissions near refineries, particularly in 

environmental justice communities. This commenter is concerned that tailpipe reductions will 

be offset by emissions increases from refineries. The commenter is also specifically concerned 

that the sulfur removed from gasoline will be emitted to the air as SO2.

Commenter: Concerned Citizens Around Murphy

Our Response:

Overall, the Tier 3 rule will deliver significant emissions and air quality benefits to 

communities across the U.S., including environmental justice communities, especially as a result 

of the near-roadway emissions reductions that will begin occurring in 2017. 

While Tier 3 standards will result in very large emission reductions from both new and 

existing vehicles, the additional gasoline hydrotreating will also cause a relatively small increase 

in emissions at the refinery. EPA analyzed these impacts in detail using our refinery-by-refinery 

analysis and concluded that even in the worst case, the emissions would be sufficient to cause 

only a small number of refineries to trigger the need for new permits (see Section V.K of the 

preamble and Chapter 5.4 of the RIA). Concerns that the sulfur removed from the gasoline might 

increase emissions of SO2 are unfounded, as the process of desulfurizing the gasoline results in 

elemental (solid) sulfur being removed, which is then sold as a byproduct by the refinery for 

other purposes. 

In all cases both minor and major NSR permit applications are subject to public 

comment. For any federal NSR permit applications submitted to EPA Regional Offices, we are 

committed to assisting members of the local EJ communities in understanding the applications 

and our proposed permits, in offering comment, and participating in our decisions, consistent 

with our EJ2014 implementation plan, Considering Environmental Justice in Permitting. 

See http://www.epa.gov/environmentaljustice/resources/policy/plan-ej-2014/plan-ejpermitting-2011-09.pdf

3.3.2. Benefits of this Rule that are Based on Reduction in UFP are Erroneous

What Commenter Said:

Commenter: Truck and Engine Manufacturers Association (EMA)

As with most of its significant rulemakings impacting mobile sources, the Preamble to the Tier 3 

Rule provides an overview of EPA’s perspective on the potential health impacts of air pollution, 

including the air pollution constituents that are emitted from motor vehicles. (78 Fed. Reg. at 

29829-29850.) While a detailed response to all of EPA’s “overview” is beyond the scope of 

these comments, there are two clear errors in EPA’s health impacts assessment that should be 

corrected and accounted for in the Agency’s final rulemaking documents. 
Chapter 3: Emissions and Air Quality Emissions Impacts

3-72

The first error relates to EPA’s assertions regarding the purportedly unique health impacts that 

can be ascribed to ultrafine particles (“UFPs”). EPA cites its own Integrated Science Assessment 

(“ISA”) published in 2009 as support for its assertions. (78 Fed. Reg. at 29831.) However, and 

contrary to EPA’s claims, more recent work published by the Health Effects Institute (“HEI”) in 

January 2013 – HEI Perspectives 3, “Understanding the Health Effects of Ambient Ultrafine 

Particles” – has shown that the available data do not support a conclusion that UFPs play any 

unique or significant role in engendering potential adverse health effects. In that regard, the 

overall conclusions of HEI’s expert panel bear repeating: 

While selected [animal exposure] studies show evidence for UFP effects, the current evidence, 

when considered together, is not sufficiently strong to conclude that short-term exposures to 

UFPs have effects that are dramatically different from those of larger particles....There are no 

long-term animal exposure studies of UFP health effects.

One explanation that must be considered for the [epidemiologic] results to date is weakness in 

the true underlying relationship between UFP exposures and adverse effects – that the null 

hypothesis being tested by these studies is true. 

The available observational study designs have also not been able to clearly demonstrate whether 

UFPs have effects independent of those for related pollutants....No epidemiologic studies of 

long-term exposures to ambient UFPs have been conducted. 

Toxicological studies in animals, controlled human exposure studies, and epidemiologic studies 

to date have not provided consistent findings on the effects of exposures to ambient levels of 

UFPs, particularly in human populations. The current evidence does not support a conclusion 

that exposures to UFPs alone can account in substantial ways for the adverse effects that have 

been associated with other ambient pollutants such as PM2.5. (HEI Perspectives 3, p. 5.) 

Thus, to the extent that the proposed Tier 3 Rule is premised on any projected amelioration of the 

health effects ascribed to ambient exposures to UFP, that purported justification for the 

rulemaking is unfounded and in error, as evidenced by the scientific findings developed 

subsequent to EPA’s 2009 ISA. As a result, EPA should correct that error in the Agency’s final 

rulemaking record. 

Our Response:

EMA comments that any projected benefits of this rule that are based on reduction in 

UFP are erroneous. The quantified PM-related benefits associated with this rule are based on 

reduction in emissions that affect ambient concentrations of PM2.5 mass, not UFP. Reduction in 

UFP concentrations is not a significant premise for the Tier 3 standards. However, we 

qualitatively summarize EPA’s most current assessment of UFP health effects, reported in the 

2009 ISA, as part of our broader summary of evidence related to PM health effects in Section 

II.B.2 of the preamble to the final rule.
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EPA will consider the HEI publication as part of its review of the larger body of evidence 

for PM health effects when developing the next PM ISA during the next review of the PM 

NAAQS. The HEI study does not substantively change our assessment of the benefits associated 

with the Tier 3 rule.
Tier 3 Summary and Analysis of Comments

4-1

4. Proposed Vehicle Emissions Program

4.1. LD Exhaust Standards

4.1.1. General

4.1.1.1. Comments Generally Supportive of the Proposed Standards and Program

What Commenters Said:

Consumers Union

New car buyers will also benefit. Starting in 2017, new cars will have tighter limits on tailpipe 

emissions, including carbon monoxide and benzene, which can linger in garages and even 

attached residential living space (4). The proposed rule also offers automakers an incentive to go 

beyond the minimum 8-year/ 80,000-mile warranty currently required for emissions control 

systems, and extend it to 15-years/150,000 miles for new vehicles. This move could improve 

reliability and lower costs to maintain emissions control systems. 

Pennsylvania Department of Environmental Protection (DEP)

The proposed vehicle standards would reduce tailpipe and evaporative emissions from passenger 

cars, light-duty trucks, medium-duty passenger vehicles, and some heavy-duty vehicles. These 

proposed vehicle standards are intended to harmonize with California’s Low Emission Vehicle 

program, creating a federal vehicle emissions program that would allow automakers to sell the 

same vehicles in all 50 states. 

DEP supports EPA’s proposed Tier 3 emission standards for vehicles. The proposed standards 

would be met by vehicle manufacturers beginning in model year 2017 and phasing in through 

later model years. Vehicles sold in states such as Pennsylvania that have adopted light-duty 

vehicle emission standards promulgated by California Air Resources Board (CARB) will be 

meeting the same standards for model year 2015 and later vehicles. States that adopted CARB 

light-duty vehicle standards comprise nearly 50 percent of the national market for these vehicles. 

Technological developments in the automotive field that have already occurred or that are in the 

developmental pipeline as a result of CARB and EPA efforts will allow automobile 

manufacturers to effectively meet these more stringent standards for NOx, VOC, and PM2.5 by 

the year 2021. 

Southern California Association of Governments (SCAG)

SCAG supports efforts to minimize emissions from vehicles, and has included a regional clean 

freight corridor system in the recently adopted 2012-2035 Regional Transportation 

Plan/Sustainable Communities Strategy. SCAG has also been active with our partner agencies in 

Plug-in Electric Vehicle readiness planning. 

Our Response:
Chapter 4: Proposed Vehicle Emissions Program

4-2

EPA acknowledges the general comments in support of the proposed standards.

4.1.1.2. Harmonization with CA LEVIII Standards

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

And I also want to thank the California Air Resources Board for its role in coordinating with 

EPA to help ensure harmonization of the LEV III and Tier 3 regulations.

So why do auto makers support this proposal? Well, Tier 3 brings a harmonized approach, as 

you’ve heard today. It builds upon the successes we’ve had in the national greenhouse gas and 

fuel economy programs. It stays true to the simple principle of providing the cleanest vehicles to 

everyone nationally. And it provides the fuels that we need. 

American Honda Motor Co., Inc.

Much has been said during the past few years about the importance of regulatory harmonization. 

With near unanimity, the auto industry supported the 2012-2016 and 2017-2025 vehicle 

greenhouse gas standards, in large part because it represented a national, unified solution to a 

complex set of competing federal and state standards. Honda produces a wide range of vehicles 

for an equally wide demographic of buyers that requires multidimensional considerations about 

what to produce, how many to produce, the cost to produce our products, and where those 

models will most likely be purchased. Having to deal with competing federal and state regulatory

requirements only complicates those decisions further.

As the EPA considers setting Tier 3 vehicle emissions and fuel requirements, we urge the agency 

to harmonize – to the greatest extent possible – with California’s LEV III regulations, including 

certification fuel characteristics and market fuel characteristics. Doing so would enable one fleet 

of vehicles to meet all U.S. regulations, substantially easing both the regulatory burden and cost 

of complying – letting us provide our customers greater affordability – and allowing us to design 

our vehicles to maintain consistent performance and emissions durability across the nation. 

One of the more important regulatory achievements of this administration has been its actions to 

harmonize the federal fuel economy and vehicle greenhouse gas regulations with those of 

California. A harmonized set of tailpipe emissions and fuel regulations would complement a key 

objective laid out by President Obama in the May 21, 2010 White House memorandum. It states: 

“The national program should seek to produce joint Federal standards that are harmonized with 

applicable State standards, with the goal of ensuring that automobile manufacturers will be able 

to build a single, light-duty national fleet.” We couldn’t agree more. Honda urges the agency to 

finalize a set of standards that offers the greatest degree of harmonization with state standards, as 

well as to ensure that the fuel operated in these vehicles will accommodate the advanced 

emissions control systems needed to meet the proposed standards. 
Tier 3 Summary and Analysis of Comments

4-3

Honda urges the Agency to finalize a set of standards that offers the greatest degree of 

harmonization with State standards, as well as to ensure that the fuel operated in these vehicles 

will accommodate the advanced emissions control systems needed to meet the proposed 

standards.

BMW of North America, LLC

BMW commends EPA for their collaboration with ARB and with the automakers toward a single 

national program for criteria pollutants in developing the complex regulation proposal which will 

substantially impact emissions for vehicles beyond a decade to 2025. 

In addition to improving air quality across the country, a single national program of harmonized 

standards would allow for wise financial and resource investments by the auto industry, as well 

as increased energy security for the nation. 

Through a variety of ground breaking engine technologies, BMW has substantially decreased the 

criteria emissions of its fleet since the adoption of Tier 2 Motor Vehicle Emission Standards. 

BMW has maintained a leading role in deploying innovative engineering solutions to meet the 

challenge of stricter emission standards: BMW engines have won numerous engine awards 

among others for High Precision Direct Injection, twin-scroll turbocharger, and BMW 

Valvetronic fully variable valve control. 

To that end, compliance flexibility and adequate lead time are two key factors which can create 

the required boundary conditions for development of innovative and creative engineering 

solutions and achievement of product maturity aimed to meet ambitious emissions standards. 

50-State Certification and Harmonization Tier 3 / LEV III: BMW strongly supports one of the 

primary goals in the Tier 3 regulation - harmonization of the federal and the California criteria 

emission programs. Any continuation of two different standards needs to allow the 

manufacturers the possibility to choose between the standards and mutual recognition. 

Harmonization is still needed for ARB and U.S. EPA in the areas of vehicle standards, test 

procedures, and certification processes in order to establish a common set of vehicle criteria 

emission standards nationwide. 

California Air Resources Board (CARB)

The California Air Resources Board (CARB) is fully supportive of the proposed Tier 3 federal 

test procedure (FTP) and supplemental federal test procedure (SFTP) requirements. With a few 

exceptions, the proposed requirements mirror the Low- Emission Vehicle (LEV III) requirements 

effectively addressing manufacturers’ concerns regarding compliance with both national and 

California emission programs. In order to further harmonize program requirements of both 

agencies, CARB intends to align the LEV III rule with a number of the Tier 3 FTP and SFTP 

requirements after Tier 3 is finalized as noted below and offers the following comments on the 

proposal. 
Chapter 4: Proposed Vehicle Emissions Program

4-4

CARB shares U.S. EPA’s goal of reducing vehicle emissions to improve air quality. Despite 

significant progress in reducing smog-forming and particulate matter emissions from the 

passenger vehicle fleet, California needs further reductions in order to meet state and federal 

ambient air quality standards. To help achieve these standards, CARB adopted the LowEmission Vehicle (LEV III) regulations last year as part of our Advanced Clean Cars program. 

The Advanced Clean Cars program combines the control of smog-causing pollutants and 

greenhouse gas emissions into a single coordinated package of requirements for model years 

2015 through 2025 and assures the development of environmentally superior cars that will 

continue to deliver the performance, utility, and safety vehicle owners have come to expect. 

CARB is mindful of the cooperative effort between CARB and U.S. EPA in the development of 

the new vehicle exhaust: emission standards for California’s LEV III program and the federal 

Tier 3 program. It is our intent to evaluate the Tier 3 rule once it is finalized to determine where 

it is appropriate to further align the LEV III regulation with the federal rule, without sacrificing 

the stringency and emission benefits of the LEV III program. Since any delay in finalizing Tier 3 

would potentially impact the implementation date of this important program, CARB urges U.S. 

EPA to proceed, expeditiously to finalize the program before the end of this year. We also look

forward to continue working with U.S. EPA in an attempt to resolve any remaining differences 

between the two programs after the Tier 3 regulations are finalized. 

Our primary goal continues to be improving air quality in California. To this end, California has 

a separate and unique Zero-Emission Vehicle Program, which we will, continue to pursue in 

order to ensure the prompt and successful deployment of advanced technology zero-emission 

vehicles. Accordingly, any determination of the extent to which it would be appropriate for 

California to incorporate elements of the Tier 3 program into our light-duty vehicle program 

would need to take into consideration our ability to sustain progress towards California’s long 

term plans for transforming the vehicle fleet for reduction of criteria pollutants. In addition, any 

modifications to the LEV III program must be structured to assure that the emission reductions 

provided by the California program will be maintained. 

Chrysler Group LLC

Chrysler strongly supports harmonization of the federal Tier 3 regulations with California LEV 

III regulations. As such, we urge EPA to make the necessary adjustments as suggested below and 

as suggested in the Alliance’s comments to truly achieve the goal of One National Criteria 

Emissions Program that includes one certification fuel with harmonized test procedures and 

certification processes. 

Cummins Inc.

In this rulemaking, EPA proposes to coordinate its Tier 3 program for reduction of tailpipe and 

evaporative emissions closely with California’s LEV III standards and with EPA’s and 

California’s greenhouse gas requirements for light-duty vehicles. Cummins strongly supports the 

goal of harmonization with California and other requirements. Consistency between EPA and 

California programs would allow manufacturers to design products for 50 states and help avoid 

the additional costs of parallel design, development, calibration, and manufacturing. 
Tier 3 Summary and Analysis of Comments

4-5

Ford Motor Company (Ford)

Harmonization: Consistent with the approach taken in the One National Program (ONP) for 

Corporate Average Fuel Economy (CAFE) and Greenhouse Gas (GHG), the proposed Tier 3 rule 

is closely aligned with California’s Low Emission Vehicle (LEV III) emissions program. This 

alignment will allow automakers to design and build a single model that can be tested once and 

sold nationally. We appreciate the significant efforts made by both EPA and California Air 

Resource Board (CARB) to harmonize the Tier 3 and LEV III requirements, and we encourage 

the Agencies to continue to work with Industry to minimize any remaining differences in the two 

programs, while retaining the interim provisions finalized in LEV III. 

I want to thank EPA and the California Air Resources Board for their efforts to harmonize 

regulations to improve air quality. Ford supports this effort, and will continue working to 

improve air quality while harmonizing standards.

Tier 3, working in concert with LEV III, helps provide clean vehicles to all 50 States. It allows 

auto makers to design and build a single model rather than two versions meaning different 

requirements, test and certify a national vehicle one time. And importantly, it provides a step 

towards the fuels needed to meet these standards.

We appreciate the significant efforts made by EPA, both EPA and CARB, to harmonize Tier 3 

and LEV III rules, and we encourage the Agency to continue to work with industry to minimize 

remaining differences in the two programs.

General Motors LLC (GM)

GM appreciates the efforts of EPA and the California Air Resources Board (CARB) staffs 

working together and with industry toward a harmonized national program for criteria emissions, 

with the goal of enabling manufacturers to design, develop, certify, build, and sell the same clean 

vehicles throughout all fifty states. This will allow our engineers to focus on a single emissions 

control system for criteria emissions, and builds upon the single national program for greenhouse 

gas (GHG) emissions and fuel economy (FE). A national approach is especially important given 

the scope of the challenges we are facing today to meet increasingly stringent GHG/FE standards 

and other regulatory requirements while simultaneously needing to meet all customer demands in 

an intensely competitive market. 

One of the biggest challenges in integrating the California LEV III program into a national 

program occurs during the first couple of years of the program. Transitioning from a program 

covering about a third of nationwide volume to a national program covering 100% of nationwide 

volume presents challenges in ramping up both the exhaust and evaporative requirements to 

national levels. 

These approaches will move us to a national program as soon as practicable and facilitate 

compliance based on a single 50-state fleet rather than separate compliance determinations for 

California/177 States versus the remaining U.S. states. GM supports such a 50-state compliance 

approach, not just for the FTP NMOG+NOx fleet average and the evaporative phase-in, but for 
Chapter 4: Proposed Vehicle Emissions Program

4-6

other fleet averages and phase-ins as well including the SFTP fleet average, evaporative fleet 

average and 3 mg/mi PM phase-in.

That brings me to the key reason we are here today, working closely with the EPA and the other 

stakeholders to achieve a harmonized and appropriate structure Tier 3 program. The 

establishment of a single national standard for fuel economy and CO2 regulation was quite 

simply a much needed breakthrough that will enable more timely and efficient introduction of 

technologies customers, manufacturers, and regulators want to succeed.

We know that EPA and California are committed to further reducing tailpipe criteria emissions, 

and in order to achieve the level of reduction proposed, our vehicles will be so clean there will be 

no reason to have competing regulatory requirements.

Our precious engineering resources are already stretched thin, and requiring them to design, 

develop, and certify two of everything I think we can all agree is counterproductive. We need to 

be able to focus on developing one of everything, which we can then sell throughout the U.S. to 

provide everyone here the cleanest vehicles in the world. A harmonized Tier 3 program properly 

structured can achieve this.

Hyundai Motor Group

As you know, this harmonization is very important for us and the auto industry as it allows us to 

design to one national standard. Additionally, we have found it very beneficial that EPA was 

willing to provide many opportunities to meet with industry and other stakeholders to discuss the 

provisions of the rule while they were under development.

As I mentioned already, Hyundai Motor Group is pleased with EPA’s efforts to align the Tier 3 

rule with CARB’s LEV III program. It’s challenging to meet different requirements for various 

regulatory agencies, particularly when it comes to testing. Having one consistent national 

standard will increase laboratory throughput in addition to design and development cost savings.

We realize that there are challenges in adopting the same provisions as CARB, but we hope that 

EPA and CARB will continue to work together to try to resolve as many of the remaining 

differences as possible. 

Manufacturers of Emission Controls Association (MECA)

MECA applauds EPA for developing a Tier 3 proposal that will establish a national set of 

exhaust and evaporative emission standards for light-duty and medium-duty vehicles by largely 

harmonizing their proposal with California’s LEV III requirements. 

Johnson Matthey

Furthermore, California has already set in motion its own tightened emission limits known as 

LEV III, which are very similar to the Tier 3 proposal. This means our industry already has no 

choice but to implement technologies for LEV III that will clearly also meet the Tier 3 proposed 
Tier 3 Summary and Analysis of Comments

4-7

limits. Thus, the adoption of the Tier 3 proposals would bring efficiencies to the industry by 

having one common set of emissions to achieve for the U.S. market.

Mid-Atlantic Regional Air Management Association Inc. (MARAMA)

By harmonizing vehicle emission standards across the country, Tier 3 would facilitate 

compliance by automobile manufacturers. The automobile manufacturers support Tier 3 because 

it enables them to harness economies of scale by deploying advanced emission control 

technologies in all new vehicles sold nationwide. 

Mitsubishi Motors R&D America, Inc (MRDA)

We believe that harmonization with the California LEV Ill Program (LEV Ill) must be EPA’s top 

priority when finalizing this rulemaking. As EPA notes numerous times in the proposed 

rulemaking, it is extremely important to automotive manufacturers that a single fleet of vehicles 

can be designed and produced for all 50 states, and be in compliance with the Tier 3, LEV III, 

and Federal Greenhouse (GHG) and Corporate Average Fuel Economy (CAFE) requirements. 

Although EPA indicates that harmonization with LEV III is a guiding principle in developing 

these proposed regulations, there are still significant gaps that remain in achieving this necessary 

goal. A harmonized program would allow manufacturers to develop cost-effective processes and 

to deploy advanced technology vehicles in meeting these standards. Smaller companies, like 

Mitsubishi Motors, have less financial resources and fewer vehicle lines to implement major 

changes in a cost-effective manner, which makes the proposed compliance flexibilities (phaseins, early credits, interim in-use standards, etc.) outlined in the NPRM extremely important.

Mitsubishi Motors supports the intent to harmonize the proposed Tier 3 program with 

California’s LEV III program. 

Motor & Equipment Manufacturers Association (MEMA)

The EPA’s proposal is mindful of other regulatory frameworks and compliance regimes. Efforts 

to harmonize Tier 3 vehicle emission requirements nationwide and to choreograph the timing of 

Tier 3 implementation with the final rules for greenhouse gas (GHG) emissions and corporate 

average fuel economy (CAFE) standards for light-duty vehicles are critical for interconnected 

and highly complex vehicle manufacturing supply chains. Also, EPA’s integrated systems 

approach to vehicles and fuels, combined with the alignment to other parallel regulations, is 

practical and cost-effective. Companies and government entities alike will benefit from the 

resulting outcomes, such as streamlined costs for R&D and production and reduced burden for 

multiple, overlapping testing and compliance protocols. Since the timing of this rule is critical, it 

is important that EPA not delay its completion. If delayed, the benefits of synchronizing the 

timing of the GHG emissions, CAFE standards, and other programs will be lost and may 

negatively impact the states in achieving their respective air quality goals.

MEMA urges EPA to fully consider the public comments, particularly from the vehicle 

manufacturers. In addition, EPA must continue to collaborate with states, like California, and 

other stakeholders to avoid divergent policy pathways and competing regulatory regimes. 
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MEMA recommends that the Agency promulgate a final rule by end of 2013 in order to match 

with other regulatory requirements standards affecting MY 2017 vehicles. 

National Automobile Dealers Association (NADA)

Harmonized Emissions Mandates, Lead Time, Durability and Other Technical Standards: Last 

year, the California Air Resources Board (CARB) finalized its Low Emission Vehicle (LEV) III 

regulations. In order to minimize compliance costs and maximize compliance flexibilities, EPA’s 

final Tier 3 regulations should encourage if not mandate that CARB harmonize with the federal 

scheme. Among other things, this means that fleet average emissions compliance should be 

based on a manufacturer’s nationwide sales. (See also 4.1.5.8 re: nationwide compliance 

demonstration.)

New York State Department of Environmental Conservation

New York has a long history of adopting California’s motor vehicle emissions control programs 

to achieve its air quality objectives. New York most recently adopted the California Advanced 

Clean Cars emissions program, which included the LEV III standards, in 2012 to achieve and 

maintain reductions of criteria and greenhouse gas pollutant emissions.

Tier 3 should be harmonized with LEV III as quickly as possible. 

The Department strongly supports this effort to harmonize federal emissions standards with 

California’s technology forcing LEV III standards. In order to maximize the air quality benefits 

of harmonization, as well as reduce the industry compliance burden, Tier 3 should reach LEV III 

stringency as quickly as possible. 

Northeast States for Coordinated Air Use Management (NESCAUM)

By harmonizing vehicle emission standards with those in the California program, Tier 3 would 

facilitate compliance by automobile manufacturers, enabling them to harness economies of scale 

by deploying advanced emission control technologies in all new vehicles sold nationwide.

Pennsylvania Department of Environmental Protection (DEP)

DEP also supports EPA’s efforts to harmonize a national emission standard program with 

CARB’s emission standards. This harmonization will allow automobile manufacturers to design, 

produce and test vehicles that meet the same standard by the year 2021. The automobile 

manufacturers also appear to support this effort because they recognize that some cost-savings 

benefits will result from producing vehicles meeting the same national standard. Clearly, 

harmonized programs would be significantly beneficial for both the environment and consumers. 

The EPA should harmonize the phase-in of light-duty vehicles in the Tier 3 program with 

CARB’s LEV III Program. While EPA’s proposal would result in the same emission standards 

for model year 2025, the phase-in schedule lags slightly behind the schedule finalized by 

California. Given the issues with fleet turnover limiting emission benefits and the fact that 
Tier 3 Summary and Analysis of Comments

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manufacturers would already have developed the technology for light-duty vehicles to meet the 

schedule that California is setting, EPA should finalize an emission standard phase-in that is 

harmonized nationally. 

Nevertheless, DEP has concerns about ... some elements of the proposed Tier 3 program that are 

not harmonized with California’s Low Emission Vehicle III Program. DEP requests that EPA 

examine and address these issues before finalizing the Tier 3 rule. 

Respiratory Health Association (RHA)

Harmonizing Federal standards with California vehicle emission standards will bring deserved 

and equitable relief from local pollution beginning in 2017. Late is better than never, and the 

proposed Tier 3 rules uses a smart systems approach that treats fuel and the engine as 

intertwined. It is the most cost-effective way to tackle the problem posed by the emissions for 

millions of vehicles, and it will improve the lives and health of people living with or who face 

increased risk of lung disease. We need EPA to finalize the strongest Tier 3 standards possible. 

Southern California Association of Governments (SCAG)

SCAG appreciates EPA’s efforts to harmonize the national vehicle tailpipe and evaporative 

emission and gasoline fuel sulfur content standards with California standards. 

SCAG also applauds EPA’s close coordination with California’s programs for greenhouse gas 

emissions from light-duty vehicles. 

There appears to be some differences between the proposed Tier 3 standards and California’s 

LEV III Regulations and California gasoline sulfur content standards. While acknowledging the 

complexities and nuances of these programs, harmonization of the proposed Tier 3 with the 

California program is important from a business and manufacturer continuity perspective. We 

believe that such harmonization may yield savings to California residents through the 

efficiencies of scale in the production of vehicles that meet one national standard. 

Truck and Engine Manufacturers Association (EMA)

In this rulemaking, EPA proposes to coordinate its Tier 3 program for reduction of tailpipe and 

evaporative emissions closely with California’s LEV III standards and with EPA’s and 

California’s greenhouse gas (“GHG”) requirements for light-duty vehicles. EMA fully supports 

the goal of harmonization with California’s standards and other emissions-related requirements. 

Indeed, EMA has long supported harmonized, nationwide programs for regulating emissions 

from heavy-duty engines and vehicles. For example, most recently, EMA supported – and 

continues to support – nationwide harmonization of the OBD program for heavy-duty vehicles as 

well as a single national program for reducing GHG emissions. 

In the context of the Proposed Tier 3 Standards, EMA supports harmonization where such 

standards are technologically feasible and reasonable in light of the myriad requirements facing 

manufacturers now and in the near future. At the same time, EPA must recognize the inherent 
Chapter 4: Proposed Vehicle Emissions Program

4-10

need for adequate leadtime and so must provide sufficient time for the implementation of any 

new, aligned standards as well as an adequate period of stability between standard changes to 

provide manufacturers an opportunity to recoup the investment required to meet the new 

standards. Consequently, EPA must continue to work with California to assure the coordinated 

and timely implementation of changes in California’s regulations where needed to achieve 

desired 50-state harmonization.

- Assure full alignment between EPA and ARB standards where reasonable and feasible, while 

meeting EPA’s obligations to finalize regulations that are both technologically feasible and 

provide the necessary and required leadtime and period of stability 

As you know, EMA and its members have been long-time proponents of regulatory alignment in 

the United States and beyond. We urge ARB and CARB to work together to assure that LEV III 

and Tier 3 are aligned in both intent and practice. 

U.S. Coalition for Advanced Diesel Cars

However, it is vitally important that the Tier 3 rule and its implementation schedule be 

harmonized with the California LEV 3 program so vehicle manufacturers and their suppliers can 

focus their innovation, investments and related efforts on delivering clean advanced technology 

cars and trucks to a national market. 

Volvo Car Group

VCG supports the effort of the EPA to work with the California Air Resources Board (CARB) 

towards a possible harmonization of the Tier 3 and LEVIII program. 

It is therefore extremely important that the EPA, CARB and the industry continue to work 

together to achieve harmonization. 

Our Response:

EPA received numerous comments favoring close harmonization between the existing 

California LEV III program and Tier 3 from a wide range of commenters, including vehicle 

manufacturers, suppliers, auto dealers, states, NGOs, and private citizens. The Tier 3 standards 

we are finalizing are closely coordinated with the LEV III program to create a vehicle emissions 

program that will allow automakers to sell the same vehicles in all 50 states.

1

 We have worked 

closely with individual vehicle manufacturers and their trade associations, who have emphasized 

the importance of a harmonized national program. Together, the Tier 3, 2017 LD GHG, and 

LEV III standards will maximize reductions in criteria pollutants, GHGs, and air toxics from 

motor vehicles while streamlining programs and enabling manufacturers to design a single 

vehicle for nationwide sales, thus reducing their costs of compliance. In this way, the Tier 3 

 

1

In December 2012 EPA approved a waiver of Clean Air Act preemption for the California Air Resources Board’s 

(CARB’s) LEV III program with compliance beginning in 2015. Twelve states adopted the LEV III program under 

Section 177 of the Clean Air Act. These states include Connecticut, Delaware, Maryland, Maine, Massachusetts, 

New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Washington, and Vermont.
Tier 3 Summary and Analysis of Comments

4-11

program responds to the May 21, 2010 Presidential Memorandum that requested that EPA 

develop a comprehensive approach toward regulating motor vehicles, including consideration of 

non-GHG emissions standards.2

We worked closely with CARB and the vehicle manufacturers, the latter both 

individually and through their trade associations, to align the two programs. The Tier 3 program 

is identical to LEV III in most major respects for light-duty vehicles (and heavy-duty vehicles, as

described in the preamble and in this Summary and Analysis of Comments document). The 

levels and timing of the declining fleet-average NMOG+NOX standards are identical to those in 

LEV III. Also, the final Tier 3 emissions bins to which manufacturers will certify individual 

vehicle models in order to comply with the fleet-average standards are also identical to those in 

LEV III. Similarly, the light-duty Tier 3 FTP PM standards and percent phase-in match those for 

LEV III through MY 2024. 

Some commenters observed that there are a few light-duty Tier 3 and LEV III provisions 

that are different. For example, the LEV III program and the Tier 3 program have different lightduty PM requirements late in the program (i.e., after MY 2024 (see Section IV.A.3.b. of the 

preamble)), and the two programs have different final NMOG+NOX standards for small volume 

manufacturers (Section IV.G.1). We are finalizing a revised SFTP (US06) PM standard, and 

CARB has indicated in their comments that it plans to take similar action in near future. Also, 

LEV III currently does not include an evaporative emissions leak test and standard; CARB has 

indicated in their comments that they plan to adopt such requirements after Tier 3 is finalized. 

CARB also indicated in their comments that they intend to consider several additional actions to 

further align several minor aspects of LEV III with the Tier 3 program once Tier 3 is finalized. 

Beyond the provisions mentioned above, the differences between the programs are not 

major and most will exist only in the transitional years of the Tier 3 program. These additional 

differences result from the fact that the LEV III requirements begin slightly earlier and that a 

limited phase-in of some provisions is necessary for a smooth transition to overall aligned 

programs. These temporary differences include the process for how early compliance credits are 

generated and used (e.g., preamble Section IV.A.7.a); how quickly manufacturers will need 

move toward certifying all of their vehicle models to longer useful-life values (e.g., Section 

IV.A.7.c) and on the new test fuel (e.g., Section IV.A.7.d); and transitional emissions bins to 

facilitate the transition from Tier 2 to Tier 3 (Section IV A.7.n). 

Because of these temporary differences between Tier 3 and LEV III, some commenters 

encouraged EPA to consider lead time and flexibility provisions to facilitate compliance as they 

relate to the period before the transitional provisions are harmonized. As discussed in the 

preamble and elsewhere in this document, we believe the proposed program design, as revised in 

light of such comments, address these concerns of the commenters.

4.1.1.3. Treating Vehicles and Fuels as a System

 

2 The Presidential Memorandum is found at: http://www.whitehouse.gov/the-press-office/presidentialmemorandum-regarding-fuel-efficiency-standards.
Chapter 4: Proposed Vehicle Emissions Program

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What Commenters Said:

Ford Motor Company (Ford)

Once again, I appreciate the opportunity to provide testimony today here. Ford will continue 

working to improve air quality while harmonizing standards in order to meet these challenging 

emissions control requirements. Treating fuels and vehicles as a system continues to be essential 

to achieving our collective air improvement goals.

Motor & Equipment Manufacturers Association (MEMA)

Also, EPA’s integrated systems approach to vehicles and fuels, combined with the alignment to 

other parallel regulations, is practical and cost-effective. Companies and government entities 

alike will benefit from the resulting outcomes, such as streamlined costs for R&D and production 

and reduced burden for multiple, overlapping testing and compliance protocols. (See also 

4.1.1.2).

Mercedes-Benz USA, LLC on behalf of Daimler AG

Treating the fuel as part of the system in total criteria emissions and Green House Gas (GHG) 

reduction is an important acknowledgement by the EPA that improvements proposed by the Tier 

3 rulemaking are possible when all contributing factors are examined and optimized.

Our Response: 

We agree with the commenters that treating vehicles and fuels as an integrated system is 

an important aspect of the Tier 3 program design. In fact, we believe that this “systems 

approach” is critical for the program to achieve its expected benefits. Section IV.A.6 of the 

preamble discusses in more detail the relationship between fuel sulfur levels and the ability of 

vehicles to meet the Tier 3 exhaust emission standards.

4.1.1.4. Interaction of Tier 3 Program with GHG Program

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

In many cases, GHG emissions reductions directly compete with criteria emissions reductions in 

the vehicle design. Recognizing the goal of aggressive, simultaneous reductions in GHGs and 

criteria emissions, automakers have worked with agency staff to develop a program that allows a 

technically feasible and cost-effective introduction of advanced technology vehicles. However, 

notwithstanding the research and dialogue that has taken place, it is impossible to accurately 

predict the pace of invention and innovation, the future fuel supply and pricing, or, most 

importantly, consumer purchasing behavior. Consequently, we suggest that the mid-term review 
Tier 3 Summary and Analysis of Comments

4-13

for the 2017-25 GHG/CAFE rule consider how the implementation of the GHG/CAFE rule is 

impacting automakers’ ability to achieve the Tier 3 requirements and vice-versa. 

Ford Motor Company (Ford)

We also encourage the agencies to evaluate the effects on new test fuel and new procedures on 

fuel economy and greenhouse gas emissions. This evaluation should consider both near-term 

impacts associated with the phase-in period of the new fuel and procedures, and the long-term 

implications of 2017 through 2025, One National Program.

Looking forward, there are other significant elements regarding future fuels and ultimately 

engine design which can have a large impact on greenhouse gas compliance. The unprecedented 

increase in CAFE standards and the associated greenhouse gas requirements are driving a 

dramatic reduction or downsizing in engine size and number of cylinders.

Pennsylvania Department of Environmental Protection (DEP)

The EPA should consider whether reducing sulfur levels in gasoline reduces or increases back 

pressure in pre-Tier 3 vehicles’ exhaust systems, and then determine whether fuel economy is 

affected positively or negatively.

If using 10 ppm sulfur gasoline in vehicles that were previously using 30 ppm gasoline 

eliminates sulfur deposition on a catalyst substrate, a small change in exhaust system 

backpressure should result. Depending on whether there is an increase or decrease in 

backpressure, the vehicle’s fuel economy would either be enhanced or harmed. EPA should 

consider this in this rulemaking. 

Our Response:

As discussed throughout the final rule, EPA has designed the final Tier 3 program in full 

recognition of the parallel implementation of the GHG standards in the same 2017-2025 time 

frame. By aligning the implementation schedules for both sets of standards, we are facilitating 

the ability of manufacturers to meet one of their stated goals, the ability to develop product plans 

that simultaneously account for the technological challenges of both programs well into the 

future. We considered the feasibility of the Tier 3 standards in the context of the established 

GHG requirements.

As part of the 2017-2025 GHG standards rulemaking, EPA committed to a midterm 

evaluation of the GHG standards for model years 2022-2025, in coordination with the California 

Air Resources Board and the National Highway Traffic Safety Administration. EPA will be 

making a determination as to whether the 2022-2025 GHG standards remain appropriate under 

section 202(a) of the Clean Air Act. In making this determination, EPA will consider a number 

of factors relevant to setting GHG standards, such as technology effectiveness, costs, leadtime, 

feasibility, and other relevant factors (see 40 CFR 86.1818-12(h)). It is important to note that the 

midterm evaluation is focused on the GHG standards for MY 2022-2025; there is not a midterm 

evaluation of the Tier 3 standards.
Chapter 4: Proposed Vehicle Emissions Program

4-14

Regarding the consideration of the potential impact on GHG emissions and fuel economy 

of sulfur deposition on catalysts, we are aware of no information to indicate a relationship 

between fuel economy/GHG emissions and sulfur deposition related to back pressure increases.

4.1.1.5. Form of the Standards

What Commenters Said:

Children’s Environmental Health Network (CEHN)

The phase-in goals for NMOG+NOx should be calculated on a per-vehicle basis (as is proposed 

for the Tier 3 PM FTP standards) as opposed to the proposed fleet-wide basis (which would 

allow manufacturers to offset higher-emitting vehicles with extra-clean models). All vehicles 

should be held to a per-vehicle emissions standard in order to best protect children’s health. 

Our Response:

We proposed the NMOG+NOx standards in terms of corporate fleet averages. We 

believe that this fleet-average approach affords manufacturers some flexibility to choose which 

technologies to implement and on what timeline, limited by the phase-in schedule and the 

increasingly stringent declining standards in this rule. We believe that this is an efficient way to 

achieve even greater AQ and health benefits than a per-vehicle approach. We believe the fleet 

average standards will provide greater AQ benefits because, when combined with the ability to 

generate credits, the fleet average incentivizes manufacturers to achieve additional reductions in 

the early years of the program when the standards are the least stringent.

In contrast, the per-vehicle standards we are finalizing for PM are not intended to force 

increasing technological improvements over time, but rather to bring all new vehicles to the 

levels being achieved by many vehicles today. In that context, fleet averaging is not appropriate, 

since our intent is for all vehicles individually to meet the standard. 

We note that the Tier 3 rule will result in very significant health benefits, including 

specific benefits to children, as described in Section VIII.B of the preamble. We are finalizing 

the form of the standards as proposed.

4.1.2. Levels of the Standards

4.1.2.1. General Comments on Level of the Standards

4.1.2.2. 120,000 Useful Life Standards

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global):
Tier 3 Summary and Analysis of Comments

4-15

The CAA is equally clear in prohibiting EPA from setting durability requirements beyond 

120,000 miles for vehicles less than 6,000 pounds GVWR. CAA § 207(c)(5)(B) states that the 

full useful life for vehicles below 6,000 pounds GVWR is 120,000 miles. In the proposed rule, 

EPA recognizes that the statute does not allow it to set durability requirements beyond 120,000 

miles for vehicles less than 6,000 pounds GVWR. To avoid the statutory requirement, EPA again 

proposes two compliance options for these vehicles. One of these options is viable for 

manufacturers, and the other one complies with the CAA durability limit:

a. 150,000 mile durability: Manufacturers can choose to certify all of their vehicles below 6,000 

pounds GVWR to the 150,000 mile fleet average standard that is harmonized with LEV III fleet 

average.

b. 120,000 mile durability: A manufacturer can choose to certify a test group to the CAA 

authorized 120,000 mile durability. However, in doing so, the manufacturer must meet a fleet 

average for its entire fleet below 6,000 pounds GVWR that is 15 percent lower than the 150,000 

mile fleet average. 

Again, EPA has created an alternative compliance option that is so punitive that it effectively 

forces manufacturers to comply with the option that violates the CAA. As discussed above 

regarding the NMOG+NOx phase-in, EPA cannot avoid compliance with the CAA by offering 

an alternative option that meets the statutory requirements, but is so burdensome that, in practice, 

it will restrict manufacturer’s choices and require compliance with the option that violates the 

statute. As explained above, several courts have held that when an agency provides a regulatory 

scheme where only one option is truly viable, the remaining option becomes a mandate. 

In this case, option (b) above is unduly onerous, because a manufacturer’s decision to certify 

even one test group to 120,000 mile durability would trigger the requirement that the 

manufacturer’s entire light-duty fleet is held to a more stringent durability standard. The 

structure of this alternative makes it clear that EPA’s intent is to drive all manufacturers to 

certify to 150,000 mile durability. 

The California LEV III requirements are based on 150,000-mile durability standards, and 

manufacturers are seeking harmonization between the Tier 3 and LEV III requirements. Even 

though the California durability requirement is not consistent with the durability limits set forth 

in the CAA, this is still no reason for EPA to either 1) violate the requirements of the CAA, or 2) 

impose another Hobson’s choice on manufacturers. 

We agree that a vehicle certifying to 120,000-mile durability should meet a more stringent 

standard than a vehicle certifying to 150,000-mile durability. Therefore, it is appropriate for 

EPA’s rules to provide that EPA will accept certification of vehicles to 150,000-mile durability 

at the CARB standards. The rules should also provide that manufacturers may certify vehicles to 

120,000-mile durability at a standard that is 85% of the proposed 150,000-mile bin standard. For 

such vehicles, the fleet average would be calculated using the corresponding 150,000-mile bin 

standard. This approach complies with the CAA without confronting manufacturers with an 

onerous choice. 
Chapter 4: Proposed Vehicle Emissions Program

4-16

Recommendation: We recommend that vehicles certifying to 120,000 mile durability be required 

to meet a “bin” standard that is 85% of the 150,000 mile bin. For calculation of the fleet average, 

the bin emissions would be the corresponding 150,000 mile bin value. For example, a vehicle 

that certified to 120,000 mile Bin 30 would need to meet a 26 mg/mile standard, both at 

certification and in use. In calculating the fleet average, the vehicle would be considered a 30 

mg/mile vehicle. 

Chrysler Group LLC:

The CAA precludes EPA from requiring manufacturers to certify their vehicles that are less than 

3,750 pounds loaded vehicle weight (LVW) and 6,000 pounds GVWR beyond a useful life of 

120,000 miles (35). EPA acknowledges this in the preamble to the proposed rule. 

Notwithstanding this clear statutory requirement, EPA proposes a regulatory structure that will 

effectively force manufacturers to certify all of their vehicles to a useful life of 150,000 miles. 

Specifically, EPA again thwarts the CAA by proposing two compliance options — one that does 

not comply with the CAA’s 120,000 useful life limitation but offers a reasonable compliance 

standard, and another that provides the required statutory useful life protection but for which 

compliance is so stringent that no reasonable company would ever choose it. 

Under the more favorable 150,000-mile useful life compliance option, manufacturers may 

choose to certify all of their vehicles below 3,750 pounds LVW and 6,000 pounds GVWR to the 

150,000 mile fleet average tailpipe emissions standard (in contravention of the CAA) that is set 

at a reasonable stringency and is harmonized with the LEV III fleet average standard. Under the 

unfavorable 120,000 mile useful life option, a manufacturer may choose to certify a test group to 

the CAA-authorized 120,000 mile useful life standard. However, if a manufacturer opts to certify 

even a single test group to the 120,000 mile useful life standard (the sole useful life authorized 

by the CAA), it must meet an unreasonably much more stringent fleet average standard for all of 

its vehicles that are less than 3,750 pounds LVW and 6,000 pounds GVWR that is 15 percent 

lower than the 150,000 mile fleet average standard. 

As with the NMOG+NOx phase-in requirements for heavy-duty vehicles, EPA has created an 

alternative compliance option that is so punitive that it effectively forces manufacturers to 

comply with the option that violates the CAA. As detailed in footnote 35, the CAA prohibits 

EPA from establishing a 150,000 mile useful life emissions standard for light-duty vehicles and 

light-duty trucks of less than 3,750 pounds LVW. And, as discussed above, EPA cannot simply 

circumvent the clear statutory limitation on useful life to 120,000 miles for vehicles less than 

3,750 pounds LVW and 6,000 pounds GVWR by offering an alternative option that meets the 

statutory requirements but is so burdensome that, in practice, it will restrict manufacturers’

choices and require compliance with the option that does not comply with the plain terms of the 

statute. Again, EPA’s dual-path approach impermissibly eviscerates the statutory limitations in 

the CAA. Providing a significantly more burdensome alternative compliance path that meets the 

statutory requirements does not, and cannot, remedy the fact that the primary compliance path 

violates the statute. 

As a general matter, Chrysler supports EPA’s attempts to harmonize standards in the Tier 3 rules 

with the California LEV III standards, which, as relevant here, require all vehicles to comply 
Tier 3 Summary and Analysis of Comments

4-17

with a 150,000 mile useful life standard. However, Congress has restricted EPA in what it can do 

under the CAA, and, absent an act of Congress, again, EPA cannot thwart the statutory 

protections contained therein. Thus, although EPA can incentivize manufacturers to certify to a 

150,000 mile useful life standard to be consistent with the LEV III program, EPA cannot 

penalize manufacturers for refusing to do so (37). Moreover, the regulatory scheme EPA 

proposed cannot be characterized as an “incentive” to manufacturers to accept a 150,000 mile 

useful life standard. Rather, for the reasons discussed below, the alternative compliance option 

EPA proposed is a penalty on manufacturers that wish to adhere to the statutory limitation to a 

120,000 mile useful life standard for vehicles less than 3,750 pounds LVW and 6,000 pounds 

GVWR. This penalty has two aspects: 

First, EPA proposes to adopt a 120,000 mile useful life NMOG+NOx emission standard that is 

85 percent of the respective NMOG+NOx 150,000 mile standard. There is no sound scientific 

basis for reducing the standard by 15 percent simply because the useful life is reduced from 

150,000 to 120,000 miles. To the contrary, the available data suggest that vehicle degradation 

flattens out considerably after 100,000 miles and, consequently, the difference in degradationrelated emissions between a vehicle that has accumulated 120,000 miles and a vehicle that has 

accumulated 150,000 miles is less than 15 percent. Catalyst degradation data obtained in 

connection with an evaluation of Chrysler aftertreatment systems indicate that the difference in 

degradation is instead approximately 10 percent. In any case, EPA may not arbitrarily establish a 

more stringent standard for the 120,000 mile useful life, without undertaking a quantitative 

analysis of emissions degradation from 120,000 to 150,000 miles that correlates to the magnitude 

of the more stringent standard for vehicles certified at 120,000 miles useful life. Accordingly, 

imposing a 150,000 mile useful life standard and a 15 percent more stringent 120,000 mile useful 

life standard are by no means equivalent from an emissions control standpoint and do not 

provide manufacturers a realistic choice. Instead, it appears that EPA is creating a 120,000 mile 

useful life standard that is artificially and unreasonably stringent—by requiring emissions 

reductions that are far disproportionate to the benefit that would result from accepting a 150,000 

mile useful life—in order to force manufacturers to select the illegal 150,000 mile useful life 

option. 

Second, EPA proposes to require that where manufacturers select the 120,000 mile useful life 

option for even a single vehicle model—and even if that specific vehicle model is unique in 

some respect or is produced in limited quantities—they must certify all of their light-duty 

vehicles and light-duty trucks to the 15 percent more stringent 120,000 mile useful life 

NMOG+NOx emissions standards (See footnote). For example, if Chrysler determines that it 

needs to retain a 120,000 mile useful life for its Dodge Viper specialty car, which constitutes 

approximately 0.1% of its total U.S. sales volume, it must meet 15 percent more stringent 

standards for its entire fleet. As with the NMOG+NOx phase-in standards for heavy-duty 

vehicles discussed above, this regulatory scheme, which sweeps in a manufacturer’s entire fleet 

if the manufacturer opts to pursue the 120,000 mile useful life option for a single vehicle model, 

is a penalty imposed on manufacturers that refuse to forego their statutory protections. And, as 

discussed above with respect to heavy-duty lead time, there is no rational basis for penalizing a 

manufacturer’s entire vehicle fleet simply because the manufacturer opts for the 120,000 mile 

useful life for a single model or test group, which it may need to do out of necessity. There is no 

rational relationship between the insignificant increase in emissions resulting from the one model 
Chapter 4: Proposed Vehicle Emissions Program

4-18

subject to the shorter useful life and the unreasonable and onerous emissions limitation that 

would be imposed across the entire fleet. Such a poison pill or hammer is so unreasonable that it 

can only be understood as a penalty for retaining the shorter useful life for even one model. 

Again, that approach is unreasonable, unfair, and unlawful. 

Chrysler nevertheless supports harmonization with the California LEV III requirements, 

especially considering that the ARB has indicated that it may refuse to accept vehicles certified 

to a 120,000 mile useful life standard as certified to the California requirements. However, EPA 

can achieve this goal without unduly penalizing manufacturers that choose to certify one or more 

test groups to a 120,000 mile useful life standard. As such, we believe EPA should, for purposes 

of these Tier 3 rules, certify the 120,000 mile Tier 3 bin standards at 90 percent of the respective 

California LEV III 150,000 mile useful life NMOG+NOx standards; but, in calculating the fleet 

averages, any such vehicle would be considered at the California LEV III 150,000 mile standard. 

Recommendation: Chrysler agrees that it is reasonable to adopt 120,000 mile Tier 3 useful life 

standards that are lower than the corresponding California 150,000 mile LEV III useful life 

standards. Chrysler recommends that EPA retain the 120,000 mile useful life NMOG+NOx bin 

standards, especially where EPA has no statutory authority to impose 150,000 mile standards. 

Chrysler also recommends that such 120,000 mile standards be set at 90 percent of the respective 

California LEV III 150,000 mile useful life NMOG+NOx standards, with fleet average 

calculations computed using the California LEV III 150,000 mile NMOG+NOx standards. 

Chrysler Footnote: EPA states in the preamble to the proposed rule that it is proposing to adopt 120,000 

mile useful life NMOG+NOx emissions standards that are 85 percent of the respective 150,000 mile 

useful life NMOG+NOx standards, see 78 Fed. Reg. at 29,868 (“Numerically, we are proposing 120,000 

mile useful life NMOG+NOx standards that are 85 percent of the respective NMOG+NOx 150,000 mile 

standards.”). The proposed rule language itself, however, provides only 85 percent fleet average 

standards, and fails to provide 85 percent bin standards. Given the description in the preamble to the 

proposed rule, we assume that this omission was simply an oversight and not intentional. However, if 

EPA decides to adopt the useful life requirements as proposed, it is critical that EPA provide in the final 

rule modified bin standards reflecting the 15 percent reduction for the 120,000 mile useful life 

NMOG+NOx standards (i.e., a 26 mg/mi bin reflecting a 15 percent reduction from the 30 mg/mi bin). 

Otherwise, EPA’s proposed rule actually would require manufacturers that choose the 120,000 mile 

useful life option to reduce emissions by more than 15 percent as compared to the 150,000 mile useful life 

option, which does not appear to be EPA’s intent.

New York State Department of Environmental Conservation

Most vehicles, excluding casualty losses, remain in service well beyond current useful life 

requirements (10 years, 120,000 miles). Consequently, New York encourages EPA to adopt 

more stringent full useful life requirements to prevent significant erosion of emission benefits as 

Tier 3 vehicles age. Specifically, EPA should adopt California’s LEV III useful life of 15 years, 

150,000 miles. 

Pennsylvania Department of Environmental Protection (DEP)
Tier 3 Summary and Analysis of Comments

4-19

The EPA is correct to extend the regulatory useful life of vehicles to 15 years or 150,000 miles 

(whichever occurs first). Motor vehicles built today can easily travel over 150,000 miles before 

reaching the end of their useful life. Therefore, raising the useful life value to 150,000 miles is 

appropriate as an option for vehicles restricted by the Clean Air Act to a 120,000 mile useful life 

and as a requirement for vehicles not so restricted. The ‘useful life’ of a vehicle is the period of 

time, in terms of years and miles, during which a manufacturer is responsible for the vehicle’s 

emissions performance. If the manufacturer certifies to the lower 120,000 mile useful life, it 

would seem that the manufacturer should multiply the proposed 150,000 mile standard to obtain 

the numerical fleet average by 0.80 not 0.85 as given in Table IV-2 due to the fact that 120,000 

miles divided by 150,000 miles equals 0.80. By allowing manufacturers to use the 0.85 factor, 

extra credit would be given to manufacturers for certifying to a lower useful life. CARB does not 

allow manufacturers to receive credit for certifying vehicles to a 120,000 mile useful life. It 

would be more appropriate for EPA to harmonize the Tier 3 requirement with the CARB would 

be more appropriate for EPA to harmonize the Tier 3 requirement with the CARB standards 

when it concerns useful life to provide the appropriate incentive to automobile manufacturers to 

produce vehicles with a longer useful life. 

Our Response:

The auto manufacturing industry has uniformly expressed the desire to produce and sell a 

single national vehicle fleet, including a general ability and willingness of the industry to certify 

their vehicles to a 150,000 mile, 15 year full useful life, as required by the LEV III program. 

However, the CAA, written at a time when vehicles did not last as long as they do today, 

precludes EPA from requiring a useful life value longer than 120,000 miles (and 10 or 11 years, 

depending on vehicle category and weight) for lighter light-duty vehicles (LDVs and LDTs up to 

3,750 lbs loaded vehicle weight (LVW) and up to 6,000 lbs GVWR (i.e., LDT1s)). For heavier 

light-duty vehicles (i.e., LDT2s, 3s, 4s, as well as MDPVs, representing a large fraction of the 

light-duty fleet), this statutory restriction does not apply, and we are finalizing a 150,000 mile, 

15 year useful life value, as proposed. 

For the lighter vehicles, we are continuing to apply the 120,000 mile (and 10 or 11 year, 

as applicable) useful life requirement from the Tier 2 program, also as proposed. (LEV III does 

not allow 120,000 mile useful life certification beyond the phase-in period and therefore vehicles 

certified as 50-state offerings under a harmonized approach will also need to comply with the 

150,000 mile useful life for LEVIII regardless of the Tier 3 120,000 mile useful life option.) For 

these lighter vehicles, manufacturers are allowed to certify to either useful life value. In order 

for the Tier 3 NMOG+NOX standards to represent the same level of stringency regardless of 

which useful life value manufacturers choose, we proposed and are finalizing proportionally 

lower numerical values (85 percent of the NMOG+NOX 150,000 mile standards based on a data 

analysis provided in Chapter 1 of the RIA) for the declining fleet average FTP NMOG+NOX

standards when a manufacturer chooses the 120,000 mile useful life for eligible vehicles. The 

RIA analysis, also provided in the draft RIA for the proposed rule, provides robust support for 

the 85-percent value for the adjustment to the NMOG+NOX standard. Commenters did not make 

any specific comments about our analysis, including providing supporting information to support 

a different percentage adjustment value.
Chapter 4: Proposed Vehicle Emissions Program

4-20

We proposed that a manufacturer that certifies any vehicle model under the 120,000 mile 

provision be required to certify all their LDVs and LDT1s to the 120,000 mile useful life and 

associated numerically lower FTP NMOG+NOX fleet average standard. Comments from the 

auto industry expressed a concern that this approach would be inflexible to manufacturers’ needs 

and unnecessarily burdensome. We disagree that the requirements proposed for the 120,000 

mile provision were punitive or create a mandate, but we have considered the concerns expressed 

by commenters and believe that the emission benefits of Tier 3 program will be maintained if 

certification of these lighter vehicles to the 120,000 mile useful life standards is allowed on a test 

group basis. Therefore we are finalizing this revised approach. 

We have also considered the comments that recommended that EPA set specific “bin” 

standards at proportionally reduced levels (factor of 0.85) for manufacturers that choose the 

120,000 mile useful life for their lighter vehicles and then include those vehicles in a single 

150,000 mile useful life fleet average as proof of compliance. We do not believe it is appropriate 

to allow a vehicle certified to (and only held to) a 120,000 mile useful life to have their projected 

emission results included with vehicles that meet the higher 150,000 mile useful life 

requirement. Manufacturers that choose the 120,000 mile useful life option likely would be 

doing so specifically to avoid any durability liability beyond the 120,000 mile point, and 

therefore their performance at the level of the standards is not guaranteed or legally required 

beyond the 120,000 mile useful life. As the analysis that we performed and that we discuss in 

Chapter 1 of the RIA was done on a fleet average basis, we believe that it is appropriate for 

manufacturers to certify each test group to the same Tier 3 ‘bin’ levels and then to average all the 

120,000 mile test groups against the “85 percent” adjusted FTP NMOG+NOX standard for that 

model year and separately average all of the 150,000 mile test groups to the unadjusted standard. 

Manufacturers are required to maintain separate 120,000 mile and 150,000 mile fleet averages if 

they choose to certify some vehicles to the lower useful life standards. With this continued focus 

on respective fleet average standards for 120,000 mile and 150,000 mile useful life test groups, 

we do not see an additional value to creating different sets of bins given the existing variety of 

certification bins available above and below the two separate fleet average standards throughout 

the phase-in and into the final program.

4.1.2.3. Specific Comments on FTP NMOG+NOx Standards

What Commenters Said:

Manufacturers of Emission Controls Association (MECA)

Two recent research programs have discussed pathways to reaching Tier 3, Bin 30 exhaust 

standards with a light-duty diesel vehicle. The first of these is the Cummins Advanced 

Technology Light-Duty Diesel Aftertreatment System (ATLAS) program, sponsored by the U.S. 

Department of Energy (DOE). Details of this project were presented at the 2012 DOE DEER 

Conference held in Dearborn, MI (see: 

ww1.eere.energy.gov/vehiclesandfuels/resources/proceedings/2012_deer_presentations.html, 

presentation by Mr. Cary Henry, Cummins, Inc.) and included in SAE paper no. 2013-01-0282 

that was presented at the April 2013 SAE International Congress in Detroit, MI. Advanced diesel 
Tier 3 Summary and Analysis of Comments

4-21

emission control technologies, including a passive lean NOx adsorber and an SCR-coated DPF 

that utilizes direct ammonia reductant injection, have been combined in this program with 

advanced combustion controls on a 2.8 liter, 4 cylinder diesel engine to demonstrate a pathway 

to Tier 3, Bin 30 exhaust emissions compliance on a full-size, light-duty pick-up truck. A second 

approach to Tier 3, Bin 30 exhaust levels on a light-duty diesel vehicle was discussed by 

Southwest Research Institute in SAE paper no. 2013-01-1301 (presented at the April 2013 SAE 

International Congress in Detroit, MI). This project combines advanced diesel combustion 

technologies, including high temperature glow plugs, with a close-coupled lean NOx adsorber 

catalyst + catalyzed DPF emission system to significantly reduce cold-start emissions and 

provide a pathway to Tier 3, Bin 30 exhaust emission compliance on a 2 liter diesel-equipped 

sport-utility vehicle. 

Our Response:

EPA acknowledges these comments supporting the feasibility of the 30 mg/mi 

NMOG+NOx standard.

4.1.2.4. Specific Comments on SFTP NMOG+NOx Standards

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

SFTP Fleet Average and Family Emission Limits: Unlike Tier 3, Tier 2 (and LEV II) vehicles 

certify to a different SFTP standard scheme. Tier 2 vehicles certify to an SFTP standard based on 

the FTP bin to which the vehicle is certified, while in Tier 3 the FTP and SFTP standards are 

independent. The Tier 3 and LEV III programs both include the previous generation vehicles in 

the fleet average. Under the LEV III program, for a LEV II vehicle the certification data is used 

in the calculation of the fleet average, projected out to 120,000 miles using a deterioration factor 

or actual test results if testing was conducted using aged components. For compliance purposes 

(confirmatory and in-use), the vehicle is held to the standard to which it was certified. However, 

it appears that under the Tier 3 program, EPA will not allow projected certification data to be 

used in the fleet average calculation for Tier 2 or interim Tier 3 vehicles. Instead, a 

manufacturer-specified SFTP FEL, which a manufacturer would be held to under confirmatory 

and in-use testing, would be the value used in the fleet average calculation and would become 

the new certification standard for that vehicle. 

Under EPA’s approach of treating values used in the fleet average calculation as emission 

standards, subject to confirmatory and in-use testing, manufacturers will be forced to add a 

compliance margin when choosing an FEL under the Tier 3 program for these Tier 2/interim Tier 

3 vehicles. For example, a MY 2018 Tier 2 (a.k.a., “interim Tier 3”) vehicle with SFTP 

certification data showing emissions of 95 mg/mile projected to 120,000 miles would use a 95 

mg/mi value in the ARB’s fleet average calculation. However, under EPA’s Tier 3 program the 

manufacturer might choose an FEL of 145 mg/mile (a 35% compliance margin, which is not 
Chapter 4: Proposed Vehicle Emissions Program

4-22

atypical) to allow sufficient compliance margin given the various sources of variability (vehicleto-vehicle, test-to-test, etc.) that a manufacturer must consider relative to confirmatory and in-use 

compliance testing. 

The net effect of this difference is to unnecessarily increase the stringency of the Federal SFTP 

program over the California program. To address this difference, harmonization with LEV III 

would only be applicable to “interim Tier 3” vehicles (Bin 125, Bin 160, and the Bin 20 or Bin 

30 PZEV vehicles discussed above) and thus would only apply to a small sub-set of vehicles, and 

only then through the MY 2019. 

Recommendation: We recommend EPA adopt the following new paragraph (or changes to this 

effect) in the interim provisions of section §86.1811-17(b)(7)(iii)(C): 

“(C) For vehicles certified to bins higher than Bin 70, and Bin 30 or Bin 20 vehicles which 

received partial zero emission vehicle (PZEV) credit in California that certified to interim Tier 3 

using carryover emissions data, compliance (confirmatory and in-use) will be based on the Tier 2 

certification values contained in §86.1811-04.” 

SFTP 4,000-Mile Standard Prior to MY 2020: EPA has proposed to retain the 4K SFTP 

standards from the Tier 2 program to prevent “backsliding” for vehicles certified in the earlier 

portions of the Tier 3 program when the composite SFTP fleet average standards might allow 

room for less robust SFTP calibrations. Under the proposal, these standards would apply to all 

“Interim Tier 3 vehicles.” The agency concluded the interim SFTP standards would not need to 

apply to “Final Tier 3 Vehicles,” since their emission system designs should be sufficiently 

robust to mitigate the agency’s concern about SFTP backsliding. “Final Tier 3 Vehicles” would

include those certified to the new useful life (i.e., 150K), Tier 3 certification fuel, and new PM 

standards. All others would be considered “Interim Tier 3 Vehicles.” 

Since EPA’s definition of Interim Tier 3 Vehicles would then include all vehicles certified using 

the option to test with the California E10 certification fuel, all such vehicles would be subject to 

the interim 4K SFTP standards – even if these vehicles were certified to some of the cleanest 

bins and to 150K SFTP standards on E10. For example, a vehicle might be certified to Bin 70 or 

below, perhaps even as low as Bin 20, plus the 150K useful life (for FTP and SFTP) and the new 

PM standard, but it would still be considered “interim” because it was tested on the California 

LEV III E10 certification fuel. Such vehicles should be expected to have calibrations as robust as 

any Final Tier 3 Vehicles, including the new SFTP standards at full useful life, and should not be 

subject to the interim 4K SFTP standards. 

While we do not think there is a need for the interim 4K SFTP standards at all; if the agency is 

going to insist on retaining them it would make more sense to link these standards to the 

transitional Tier 3 bins, i.e., those above Bin 70, rather than linking them to the more complex 

definition of Interim Tier 3 Vehicles. Additionally, having this simplistic link to the bin structure 

rather than to multiple variables of the more complex Interim Tier 3 Vehicle definition would 

simplify both reporting requirements for the manufacturers and data acquisition and tracking 

burdens for the agency, and would do so without any loss of stringency or backsliding. 
Tier 3 Summary and Analysis of Comments

4-23

Recommendation: We recommend that EPA change the applicability of the 4K SFTP standard 

such that it would apply to only those bins above Bin 70 rather than to all vehicles that have been 

defined as Interim Tier 3 Vehicles through MY 2019 only. 

Interim In-Use Standards: Similarly, interim in-use standards are appropriate for SFTP for both 

the MDV and LDV classes. For the first time ever, the SFTP standards will apply at a 150,000 

mile useful life. And the required levels will be far lower than current standard levels. These two 

factors, coupled with the rapid introduction of new technologies driven by the GHG and fuel 

economy requirements, justify the need for interim in-use SFTP standards to help manufacturers 

manage their in-use compliance risk. [EPA-HQ-OAR-2011-0135-4461-A1, p. 24]

Recommendation: We recommend EPA continue the historic practice of allowing interim in-use 

standards by harmonizing with the LEV III interim in-use standards for the HDV FTP and SFTP 

requirements and the LDV SFTP requirements. 

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

In discussing the SFTP NMOG+NOx feasibility, EPA notes “The proposed new emission 

requirements include stringent NMOG+NOx composite standards over the SFTP that would 

generally only require additional focus on fuel control of the engines and diligent 

implementation of new technologies like gasoline direct injection (GDI) and turbocharged 

engines.” There are no supporting data in the DRIA to substantiate this comment and in fact the 

following section notes that “A range of technology options exist to reduce NMOG and NOx 

emissions from both gasoline fueled spark ignition and diesel engines below the current Tier 2 

standards. Available options include modifications to the engine calibration, engine design, 

exhaust system and after treatment systems.” and further add that “To achieve the NMOG+NOx 

Tier 3 SFTP standard manufacturers will need to develop and implement technologies to manage 

catalyst temperatures during high-load operation without using fuel enrichment.” 

California Air Resources Board (CARB)

CARB supports U.S. EPA’s proposal to not include relaxed interim emission standards for nonmethane organic gas (NMOG) + oxides of nitrogen (NOx) and (PM) in the light-duty SFTP 

program. CARB agrees that the technologies required for the proposed SFTP emission standards 

are well-established and interim emission standards, typically reserved for new technologies, are 

not needed. Accordingly, CARB intends to propose alignment with this proposal once the Tier 3 

program is finalized. 

International Council on Clean Transportation (ICCT)

The SFTP standards are too lenient and, as proposed, will not be effective. Current vehicles 

certified to Tier 2 bin 2 or LEVII-SULEV have average NMHC+NOx emissions of less than 10 

mg/mi, more than 80% below the proposed limit of 50 mg/mi in 2025. Similarly, the proposed

SFTP particulate standards are 3.3 times higher for vehicles 6000 GVWR than the proposed FTP 

standard. Setting the SFTP standards properly is especially important for diesel engines, as diesel 
Chapter 4: Proposed Vehicle Emissions Program

4-24

emission control hardware requirements are largely set by the high load conditions on the SFTP. 

SFTP NMHC+NOx standards should be set at no more than 20 mg/mi and SFTP particulate 

standards at no more than 6 mg/mi. 

SFTP Standards: For the most part, the overall stringency of the proposed rules is adequate and 

the provisions, including leadtime and credit provisions, are appropriate. However, ICCT is 

extremely concerned that the SFTP requirements are far less stringent than the FTP 

requirements. While the proposed Tier 3 SFTP standards are a major improvement over the

SFTP standards for Tier 2, the Tier 2 SFTP standards were unchanged in stringency from the 

Tier 1 SFTP standards and, thus, completely ineffective. Thus, despite the large reduction in the 

SFTP standard levels, the proposed SFTP standards are still far too lenient and will not achieve 

the objectives of the SFTP standards to reduce in-use emissions.

To demonstrate our concerns, we have analyzed the stringency of the proposed SFTP standards 

in two different ways. The first method compares the proposed SFTP standards against current 

SFTP emission levels. The second method compares the proposed SFTP standards against the 

proposed FTP standards.

Current SFTP emission levels: Figure 1-5 [of number EPA-HQ-OAR-2011-0135-4304] in the 

draft RIA (page 1-18), reproduced below, demonstrates that the average SFTP NMHC+NOx 

emissions for current vehicles certified to Tier 2 bin 2 or LEVII-SULEV emission standards (the 

orange bars) is less than 10 mg/mi, and the highest emissions seen is about 42.5 mg/mi. The 

proposed SFTP NMHC+NOx standard drops from 103 mg/mi in 2017 to 50 mg/mi in 2025. So, 

the proposed standard for 2017 is more than 10 times the average emissions of current vehicles 

and the proposed 2025 standard is more than 5 times the average emissions of current vehicles.

Proposed SFTP versus proposed FTP standards: The original SFTP standards, adopted in 1996 

and applied to Tier 1 vehicles, found that the incremental emissions on the SCO3 and USO6 

cycles was similar in magnitude to the incremental emissions from the cold start on the FTP. 

Thus, SFTP standards for Tier 1 vehicles were set at the same numeric level as the FTP 

standards.

As the SFTP standards are hot, running emissions only, it is appropriate to separate the FTP 

requirements into cold start emissions and hot, running emissions. The proposed NMHC+NOx 

FTP standards are 30 mg/mile. The draft RIA states (page 1-6): [EPA-HQ-OAR-2011-0135-

4304-A1, pp. 13-14] ’Based on modal analysis of a gasoline powered vehicle being operated on 

the FTP cycle, approximately 90 percent of the NMOG emissions occur during the first 50 

seconds after a cold start. In addition, about 60 percent of the NOX emissions occur in these 

early seconds.’

The Tier 2 bin 2 standards were 10 mg/mi for NMHC and 20 mg/mi for NOx. Using this ratio 

and applying it to the cold start emission ratios from the draft RIA, 70% of NMHC+NOx 

emissions on the FTP are from the cold start (90% x 1/3 + 60% x 2/3). This means that about 

30% of NMHC+NOx FTP emissions are from hot, running operation and, thus, account for 

about 9 mg/mi of the proposed FTP standards. 
Tier 3 Summary and Analysis of Comments

4-25

The proposed NMHC+NOx SFTP standards are 50 mg/mi, or 5.5 times higher than the hot, 

running emissions portion of the FTP standards. This is so lenient as to be essentially no offcycle control. And this is with respect to current vehicles, much less for 2025 with several 

additional generations of emission control development. 

After application of the standard 50 percent compliance margin, hot, running NMHC+NOx 

emissions on the FTP are about 4.5 mg/mi. Current SFTP NMHC+NOx emissions from Tier 2 

bin 2 and LEVII-SULEV vehicles are a bit less than twice this amount. This is a reasonable ratio 

between SFTP and hot, running FTP emissions. This, in turn, indicates that the hot, running FTP 

comparison supports the analysis of SFTP emissions from current vehicles. 

Both the current SFTP data and the proposed hot, running emissions on the FTP support actual 

SFTP NMHC+NOx emissions of less than 10 mg/mi. After adding the standard x2 in-use 

compliance margin, the SFTP NMHC+NOx standard should be set at no more than 20 mg/mi. 

Setting appropriate SFTP standards is especially important for diesel vehicles. The cold start in 

the FTP largely determines the emission control system design for gasoline vehicles. The 

primary need for SFTP gasoline engine standards is to ensure that proper calibrations are used 

off-cycle and that emissions remain reasonable in-use. However, for diesel engines, the emission 

control system design is largely determined by high load operation. Thus, while the proposed 

SFTP requirements would likely not impact gasoline hardware design, ineffective SFTP 

standards could lead to selection of diesel emission control systems that are less effective in-use. 

In fact, this has already been seen in Europe, where Euro IV and Euro V heavy-duty vehicles 

equipped with selective catalytic reduction (SCR) systems have significantly elevated emissions 

of nitrogen oxides (NOx) during in-use driving, particularly when operating in urban traffic. In 

some cases, actual in-use urban emission levels may be as high as or higher than those from 

much older vehicles with engines certified to more lenient emission standards (9). This illustrates 

the importance of setting emission standards using representative test procedures and appropriate 

standards. 

ICCT does have concerns in two areas. First, while the proposed supplemental FTP standards 

are a major improvement over the SFTP standards with Tier 2, they are still not stringent 

enough. The Tier 1 SFTP standards were set at the same numeric level as the Tier 1 FTP 

standards. While the proposed SFTP NMOG plus NOx standards are 67 percent higher than the 

proposed FTP standards.

Mitsubishi Motors R&D America, Inc (MRDA)

We completely agree with the Alliance and Global Automakers comments regarding concerns 

with the SFTP test. The SFTP test, which is used to calculate the NMOG + NOx fleet average, is 

a composite of the SCO3 and US06 tests. The SCO3 test is expensive and time-intensive to run, 

and the US06 is highly driver-dependent relative to any other vehicle emissions test. As the 

overall emission standards for the FTP become more stringent in the proposed Tier 3 program, 

automobile manufacturers will make significant changes to comply, e.g. changes to catalysts, 
Chapter 4: Proposed Vehicle Emissions Program

4-26

engine calibrations, and transmission gear ratios, etc. It is unknown how these changes will 

affect the SFTP emissions and therefore compliance with the new standards. 

The proposed Tier 3 program does not include early credits for SFTP compliance. Early credits 

are a necessary compliance flexibility for automotive manufacturers, since they cannot control 

for market uncertainty, i.e. which vehicles customers will purchase. It will be an unnecessary 

(and extremely challenging) compliance burden for OEMs to comply with a federal regulation 

that will not allow early credits, and with the LEVIII program that will allow early credits. This 

discrepancy between the Federal and California programs can create significant differences 

between the two sets of standards. 

Additionally, the proposed Tier 3 program does not allow for interim in-use SFTP standards, 

whereas they are included as part of the LEV III program. Without additional allowances for inuse standards during the interim years, it will be difficult for manufacturers to learn about the 

new technologies and how well they work over time. New technologies will be strongly 

penalized under the Tier 3 program in comparison to the LEV III program. For example, if an 

OEM starts basic development work in Spring/Summer 2014 in order to certify the vehicle in 

2016, calibrations can be made to meet the required standards. However, the performance of the 

vehicle over time is unknown. Therefore, interim in-use standards would help alleviate this 

uncertainty. 

Another area which demonstrates a lack of harmonization between the proposed Tier 3 program 

and the LEV III program is SFTP fleet average compliance. EPA is proposing that non-Tier 3 

(i.e. Tier 2) test groups use the Tier 3 120K Family Emission Limits (FEL) for fleet average 

certification and for confirmatory and in-use standards. EPA is effectively penalizing the Tier 2 

carryover vehicles by making it harder to meet their fleet average SFTP compliance level. This 

requirement would retroactively change fleet average compliance standards for non-Tier 3 

vehicles. Additionally, this requirement means that non-Tier 3 test groups would be counted 

differently for fleet average compliance under LEVIII and Tier 3. A lack of harmonization in this 

area will introduce a significant reporting burden for manufacturers. Duplicate certification and 

confirmatory compliance strategies will be necessary and provide no air quality benefit. Similar 

to LEV III, EPA should allow non-Tier 3 vehicles to use Tier 2 emissions certification data for 

confirmatory and in-use requirements. 

NPRM Comments: For the reasons stated above, we request the following:

-Allow early credits for SFTP compliance.

-Provide interim in-use standards for SFTP compliance.

-Harmonize with the LEVIII program for SFTP fleet average compliance by allowing non-Tier 3 

vehicles to use Tier 2 emissions certification data for confirmatory and in-use requirements. 

Supplemental Federal Test Procedure (SFTP): Allow early credits and provide interim in-use 

standards for SFTP compliance. EPA should harmonize with the LEVIII program by allowing 

non-Tier 3 vehicles to use Tier 2 emissions certification data for confirmatory and in-use 

requirements.

Natural Resources Defense Council (NRDC)
Tier 3 Summary and Analysis of Comments

4-27

Based on EPA’s own analysis of current vehicle performance, the Tier 3 standards for the 

Supplemental Federal Test Procedure (SFTP) should be more stringent. As presented in the Draft 

Regulatory Impact Analysis (DRIA), Figure 1-4, model year 2010 and 2011 vehicles certified to 

Bin 5 had average HC+NOx levels at or below EPA’s proposed NMOG+NOx standard of 50 

mg/mi for model year 2025. Further, Bin 2 vehicles, shown in DRIA Figure 1-5, had average 

HC+NOx emissions below 15 mg/mi and maximum levels below 50 mg/mi. Under Tier 3, it is 

expected that existing and new technologies enabling vehicles to reach Bin 2 and 3 levels will be 

much more widespread in the fleet. Clearly, a standard even lower than 50 mg/m is technically 

and economically feasible. 

Union of Concerned Scientists (UCS)

Millions of Americans breathe cleaner air as a result of our nation’s clean air laws but serious 

challenges remain. More than 1 in 3 Americans still live in areas where air pollutant levels 

exceed at least one of the health-based National Ambient Air Quality Standards. Passenger 

vehicles remain the second largest emitters of nitrogen oxides (NOx) and volatile organic 

compounds (VOCs) in the U.S. – the primary pollutants that form smog. These vehicles also 

emit more than half of all carbon monoxide pollution and contribute to particulate matter 

emissions. It is therefore essential that the Tier 3 standards for both PM and NMOG+ NOx be 

sufficiently stringent as to provide quantifiable and real reductions in harmful emissions. 

We urge EPA to consider levels for the SFTP for both PM and NMOG+ NOx that are 

sufficiently stringent to ensure that they are suitably protective of human health and the 

environment. 

Supplemental Federal Test Procedure: EPA should revisit the non-methane organic gas plus 

nitrogen oxides (NMOG+ NOx) and particulate matter (PM) exhaust emission requirements to 

ensure that the emission requirements of this test procedure are suitably protective of human 

health and the environment. 

We are concerned that the proposed Supplemental Federal Test Procedure (SFTP) is not 

sufficiently stringent. In 2025, the Federal Test Procedure (FTP) requires a NMOG+ NOx limit 

of 30 mg/mile, regardless of class size, while the SFTP level is 50 mg/mile. The SFTP is 67% 

higher than the FTP. Additionally, the Regulatory Impact Analysis (8) shows that the average 

SFTP NMOG+ NOx emissions for current light duty vehicles certified to Tier 2 Bin 2 are less 

than 10 mg/mile, and the highest emissions are just over 40 mg/mile. The RIA also shows that 

Tier 2 Bin 5 vehicles currently average approximately 30mg/mile for light duty vehicles and up 

to approximately 50 mg/mile for the largest light duty trucks. This means that the highest current 

Tier 2 Bin 2 and the average Tier 2 Bin 5 emitters are already compliant with the proposed 2025 

standard, and that the 2025 standard is five times the emissions of the average current Tier 2 Bin 

2 vehicle. 

Our Response:
Chapter 4: Proposed Vehicle Emissions Program

4-28

We received a variety of comments regarding the proposed SFTP standards. On one 

hand, several commenters stated that the proposed standards are too lenient, based on their 

evaluation of vehicle emission test data we presented in the NPRM. We have considered these 

comments and have reviewed the data from the NPRM. Our conclusion from that data continues 

to be that the SFTP NMOG+NOx emission levels that we are finalizing are sufficiently low to 

ensure that manufacturers will accomplish the purpose we had set out for these standards – to 

largely eliminate the use of fuel enrichment events (and their emission consequences) and 

discourage “backsliding” on SFTP emissions performance as new vehicles are developed, 

including diesels whose NOx emission control hardware requirements have historically been set 

by the high load conditions found on the SFTP. 

As a result, we designed the standards to essentially eliminate fuel enrichment events and 

their emissions consequences, thereby resulting in important emissions reductions. See Chapter 

1 of the RIA for an analysis of this data. Based on our reassessment, we continue to believe that 

significant additional real-world emission reductions will not result through SFTP NMOG+NOX 

standards lower than the 50 mg/mi fully phased-in level we are finalizing. We considered the 

analyses of commenters arguing that a lower standard is shown to be achievable by some 

vehicles today, in part based on an assumed relationship between FTP and SFTP performance. 

We do not see a strong enough relationship between these emissions to draw conclusions about 

the standard levels. As we discuss here and in the preamble, we find it more compelling to 

observe the close relationship between SFTP operation and fuel enrichment events. 

The 50 mg/mi final level of the standard ensures that over the SFTP cycles, vehicles will 

have little opportunity to deviate from the tight emission controls established for the FTP. Any 

lack of attention to the SFTP cycles will result in exceedance of the standards due to the highly 

non-linear emission performance of the emission control systems when fuel enrichment events in 

gasoline vehicles occur or when diesels do not properly control NOx aftertreatment. (To achieve 

additional meaningful reductions for SFTP “off-cycle” like operation, EPA would need to pursue 

a “not to exceed” requirement similar to what is required for heavy-duty engines; such an 

approach would require significant new research and we did not propose this for Tier 3.) Again, 

we believe that the 50 mg/mi NMOG+NOx standard will ensure that the SFTP performance of 

future vehicles with future technologies continues to be comparable to that attained by the 

current Tier 2 fleet. Finally, the fuel enrichment limitation provisions we are finalizing will 

further support the goals of SFTP standards.

On the other hand, a few commenters stated that as compared to the LEV III program, 

compliance with the Tier 3 SFTP NMOG+NOx standards, including manufacturer-selected 

FELs, is unnecessarily stringent. The LEV III program has the challenge of determining a fleet 

average for SFTP that includes LEV II vehicles previously certified only to the 4,000 mile (4K) 

standards and LEVIII certified to more stringent standards that apply to full useful life. LEV III 

allows the LEV II results to be deteriorated to full useful life for purposes of fleet average 

calculation. However these LEV II SFTP requirements remain only 4,000-mile standards. 

Unlike LEV II, the Tier 2 SFTP standards have always been full useful life (not only 

4,000-mile) standards, and we continue to require all Tier 3 vehicles to also meet full useful life 

standards. When transitioning allowable “carryover” vehicles into “interim” Tier 3, 
Tier 3 Summary and Analysis of Comments

4-29

manufacturers will need to determine the self selected SFTP FEL that they believe represents the 

full useful life performance of that vehicle. This self-selected standard will be what the 

manufacturer will be held to for in-use testing in addition to determining the fleet average level 

at certification. It is possible that the Tier 3 program may require a manufacturer to select an 

FEL that is numerically higher than the carryover LEV II 4,000-mile result with deterioration 

applied, but it is at the discretion of the manufacturer to select an FEL that represents expected 

full useful life performance. This situation, if it occurs, is not inconsistent with our overall intent 

for the SFTP standards, and we are finalizing these provisions as proposed.

Comments regarding the 4K SFTP standards for Interim Tier 3 vehicles suggested that if 

we insist on retaining this requirement, it should only apply to Bins higher than Bin 70. The 

purpose of retaining this requirement for all Interim Tier 3 vehicles is that by definition, Interim 

Tier 3 vehicles are not meeting the full requirements of Tier 3, which include the final E10 test 

fuel and the stringent PM standards for both FTP and SFTP. The 4K SFTP requirement is a very 

effective requirement for protecting against excessive PM emissions during conditions like 

aggressive or high-speed driving behavior. Until the vehicles meet the stringent Tier 3 PM 

standards for SFTP, PM emissions will generally be controlled to current Tier 2 performance 

levels by maintaining the 4K SFTP requirements. Vehicles utilizing LEV III test fuel during the 

phase-in may be considered Final Tier 3 if they meet the new PM standards and the 150,000 mile 

useful life requirements. 

Several commenters supported relaxed interim in-use SFTP NMOG+NOx standards for 

light-duty vehicles. Also, one commenter recommended adding early credit provisions for the 

SFTP NMOG+NOx standards. As discussed above, the levels of these standards are not 

intended to force major new technological improvement, and will not be challenging for most 

manufacturers for most vehicles. Based on our analysis of in-use emission performance from 

IUVP testing, as discussed in the RIA, we do not believe that interim in-use standards are 

necessary even with the increase in useful life requirements and the introduction of new 

technologies in response to GHG and fuel economy requirements, and we are therefore finalizing 

SFTP NMOG+NOx standards without associated interim in-use standards. In their comments, 

CARB supported this approach and stated in their public comments their intention to propose 

alignment with this approach once the Tier 3 program is finalized. Similarly, we do not believe 

early credits will be necessary to facilitate compliance with the SFTP standards, and we are not 

finalizing early credits for this purpose. 

API and AFPM incorrectly state that there are no supporting data to substantiate 

statements about SFTP NMOG+NOx feasibility. EPA analyzed in-use certification test results 

for model years 2010 and 2011, which represent the most recent model years for which complete 

IUVP data sets are available. This analysis can be found in RIA chapter 1.3. The analysis 

indicates that most vehicles are already meeting the final SFTP composite standard of 50 mg/mi. 

We concluded that the small number of vehicles currently not meeting the final standards will 

need additional focus on the SFTP cycles and/or possible hardware improvements to better 

manage temperature concerns. Additionally, we recognize that our analysis may not have 

included some newer technologies that have just recently entered the market and that these 

technologies may require diligent implementation to meet the Tier 3 standards. 
Chapter 4: Proposed Vehicle Emissions Program

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4.1.2.5. Specific Comments on FTP PM Standards

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

Another point of concern is that the PM standards are flat standards that all vehicles must meet, 

as compared to fleet average standards that are proposed for NMOG+NOx compliance. Thus the 

risk that a particular type of technology would be precluded by the PM standards is increased 

because such technology cannot be certified to a higher bin and offset by a different technology 

certified to a lower bin. 

It is also worth noting that the PM standards begin at a time when manufacturers enter the eighth 

year of the most stringent GHG standards in history, when the number of ZEVs and PHEVs 

jumps considerably in California and the Section 177 states, and while reducing exhaust 

emissions by 75 percent on both the FTP and SFTP and phasing in zero evaporative emission 

standards on all vehicles. 

American Lung Association

Harmonize PM Standards with CARB now. We strongly urge EPA to harmonize the Federal 

Test Procedure (FTP) PM emissions standard with CARB to 1 mg/mile by 2025. Diesel vehicles 

and some gasoline-powered vehicles have the technology to meet a 1 mg/mile PM standard 

today. According to the International Council on Clean Transportation (ICCT) in their comments 

to CARB on the Low Emissions Vehicle program III, certifying vehicles to a low standard can 

be challenging, but can be done. ICCT recommended focusing on the more precise solid particle 

number measurement such as in the United Nations Particle Measurement Programme as an 

alternative proxy, but not a replacement, for the gravimetric method. Technology exists today to 

collect and report particle number emissions. Automakers in Europe currently do so, therefore, 

given the lead time, this issue should be resolved by 2017. 

Appalachian Mountain Club (AMC)

In setting the particulate matter emissions standard and the Supplemental Federal Test Procedure 

(FTP) we urge EPA to use the lowest feasible mg/mi level supported by the EPA’s own testing 

information. In addition, the Agency should consider the current efforts by the California Air 

Resources Board for the California Low Emission Vehicle 3 standards, which is phasing in a 1 

mg/mi FTP standard starting in 2025. 

California Air Resources Board (CARB)

CARB supports the Tier 3 PM standards proposed by U.S. EPA through the 2024 model year. 

These standards, when fully implemented in 2022, represent a 70 percent reduction from current 

PM standards and will ensure new vehicles and technologies will continue to perform at levels 

achieved by the best of today’s vehicle technologies. We also agree with U.S. EPA that these 

standards are readily achievable with no additional technology or hardware. 
Tier 3 Summary and Analysis of Comments

4-31

However, the federal program does not include the LEV III 1 milligram per mile (mg/mi) PM 

standard that phases-in between model years 2025-2028, stating “In order for U.S. EPA to 

propose a standard at this level, there must be established methods to, reliably and consistently 

measure PM below that standard, for compliance purposes.’ While we understand U.S. EPA’s 

reluctance at this time due to concerns with current and proposed test methods, we encourage 

U.S. EPA to consider adoption of such a standard as discussed below. CARB is in the process of 

completing testing studies, which will show that existing methods can be modified in a 

straightforward manner to achieve accurate and repeatable measurement of sub-1 mg/mi PM 

emissions. At the same time, CARB is also pursuing additional research to explore alternative 

methods for PM measurement in order to take advantage of promising, new commercially 

available real-time instruments. We also urge U.S. EPA to re-examine the proposed PM 

standards for the SFTP for the reasons discussed below. 

CARB adopted the 1 mg/mi PM standard because PM emissions are a particular concern for 

their multiple impacts on public health, air quality, and the global climate. In general, mobile 

sources (mainly cars and trucks) are not major contributors to the statewide total PM mass 

inventory. For instance, the PM emissions from light-duty vehicles add up to less than 5 percent 

of the total California PM2.5 inventory. However, they do contribute significantly to urban 

pollution and human exposure, such as the elevated concentrations of PM near heavily-travelled 

roadways. Historically, PM emissions from diesel engines were of most concern because of their 

high PM emission rates relative to gasoline engines. But as the modern diesel engine achieves 

increasingly lower PM emissions, the interest in and relative contribution of PM emissions from 

an ever increasing number of gasoline-fueled light-duty vehicles is growing. Thus, the need for 

maximum mitigation of PM emissions at the source (i.e., tailpipe) using the most technically and 

economically feasible approach is paramount. 

Comment 1 - Harmonization of 1 mg/mi PM standard between Tier 3 and LEV III: As stated 

above, based on studies CARB and others have conducted recently, we believe the measurement 

method will not be an issue for implementing a 1 mg/mi PM standard for the 2025 model year or 

sooner. We agree with U.S. EPA on the statement that meeting the 1 mg/mi PM standard 

requires establishing methods to reliably and consistently measure PM below the standard. 

CARB, U.S. EPA, and some industry laboratories have already measured and reported PM 

emissions from light-duty vehicles well below 1 mg/mi using the existing three filter method 

prescribed by 40 CFR Part 1065. In its draft Regulatory Impact Analysis, U.S. EPA reported 

FTP composite PM emission results for 16 light-duty passenger cars and trucks (Table 1-8 of the 

Regulatory Impact Analysis). Reported PM emissions from 11 of the 13 conventional port fuel 

injection vehicles were below 1 mg/mi, ranging from 0.10 to 0.93 mg/mi. With the exception of 

a few repeat results with comparatively high variability, the data in Figure 1-8 of the Regulatory 

Impact Analysis suggests reasonably good precision and repeatability in the vast majority of the 

tests. The reason for the high variability in a few results needs investigation, but may be 

attributed to vehicle stability. Reproducibility between different tests cells and/or laboratories 

also needs to be addressed so that consistent results for certification and compliance can be 

generated within acceptable margins. 

CARB has already developed and implemented a strict laboratory filter handling and weighing 

procedure (MLD 145) that minimizes variability from the filter weighing contribution of PM 
Chapter 4: Proposed Vehicle Emissions Program

4-32

measurement. The background contribution from the Constant Volume Sampler dilution tunnel 

at CARB facilities has been determined to be no more than 2.5 micrograms per filter. The 

proposed test method in 40 CFR Part 1066 allows for a maximum background correction of 5 

micrograms per filter, which is equivalent to 0.20 mg/mi PM with nominal Constant Volume 

Sampler flow of 350 standard cubic feet per minute and no secondary dilution. Allowance for the 

correction subtracts most or all of the system’s contribution to a PM measurement. Therefore, 

manufacturers can design closer to the standard and still have a reasonable probability of passing 

a one test certification requirement.

CARB also agrees with U.S. EPA’s proposed test procedure changes that will allow the use of 

fewer filters when conducting PM measurements. Conceptually, this will reduce measurement 

variability as well as the test burden associated with weighing multiple filters. CARB is 

evaluating the various filter options proposed in 40 CFR Part 1066 and develop defined filter test 

method procedures. We expect the additional options will show even further improvement in the 

capability of the gravimetric technique for measurement of PM below 1 mg/mi. 

Given the progress to date and ongoing work, CARB anticipates that improved test procedures, 

in conjunction with the implementation of strict laboratory filter handing and weighing 

procedures, will allow consistent and reliable gravimetric PM measurement well below 1 mg/mi. 

CARB believes that the automotive industry can make the necessary changes to their emission 

certification laboratories in a timeframe that allows for an earlier implementation of the adopted 

1 mg/mi standard than the 2025 model year. To that point, CARB recommends that U.S. EPA 

consider adoption of a 1 mg/mi PM standard to be consistent with the standards CARB adopted 

in the LEV III regulations, and commit to evaluate in the near future, concurrently with CARB, 

whether the standard could be implemented even earlier than the scheduled 2025 model year 

start date. 

Comment 4 — Optional Phase-In Formula for FTP and US06 PM Standards: U.S. EPA is 

proposing to phase-in Tier 3 FTP and US06 PM emission standards beginning with the 2017 

model year with 100 percent compliance required in the 2021 model year. U.S. EPA has also 

proposed an optional alternative phase-in schedule that manufacturers may use to comply with 

the Tier 3 PM emission standards for these model years. This alternative phase-in schedule is 

based on a mathematical equation that provides credits for vehicles certified to the Tier 3 PM 

standards based on the year in which they are certified. Accordingly, vehicles certified to Tier 3 

PM standards in earlier years would be worth more than those certified in later years. This 

alternative phase-in schedule is similar to one CARB adopted for vehicles meeting the LEV III 

PM standards. However, while the LEV Ill regulations explicitly state that 100 percent 

compliance is required at the end of the phase-in period, the proposed Tier 3 regulations do not. 

We believe that in order to maintain the emission benefits of the Tier 3 program, it is necessary 

to add language to the Tier 3 rule to clarify that a manufacturer that certifies its vehicles to this 

alternative phase-in schedule must still meet the requirement that 100 percent of those vehicles 

meet the applicable PM standards in the 2021 model year. 

[See CARB’s public comment document EPA-HQ-OAR-2011-0135-4919-A1, received by the 

docket on October 23, 2013, for two graphics: CARB Light-Duty SFTP Program (PFI Vehicles) 

and CARB Light-Duty SFTP Program (GDI Vehicles)]
Tier 3 Summary and Analysis of Comments

4-33

Emissions Control Technology Association (ECTA)

Proposed Tier 3 Limits for PM is Too High: We disagree with EPA’s Tier 3 PM limit value and 

believe it is too high. 

EPA concludes that: “The intent of the proposed 3 mg/mi standard is to bring all light-duty 

vehicles to the PM level typical of that being demonstrated by most light-duty vehicles today’. 

The EPA has proposed a Tier 3 PM limit value that is too high. The 3 mg/mile proposed FTP PM 

standard is achievable in most of today’s vehicles, and by EPA’s own estimate, is not a 

challenging value. Given the toxicity of PM, wherein there is no “safe” level in ambient air, that 

some emerging engine concepts, especially GDI engines, increase and change the PM emission, 

and that many technologies are readily available to achieve much lower levels, EPA needs to at 

least match the California LEVIII 1 mg/mile limit value, harmonizing the regulation throughout 

the United States, and more-closely matching the effective level that will be implemented in 

Europe in 2017. The typical PM emission throughout the major markets in 2025 will not be 3 

mg/mi, but substantially less given the particle number limits today in Europe and Beijing, and 

being considered in Japan. Setting the bar at levels achievable today for a regulation that will be 

phased in through 2025 on such a critical emission as PM is not sound public policy, especially if 

other major markets are tightening much more. 

Numerous approaches exist to bring the most difficult engine type, GDIs, into tighter PM 

compliance; namely fuel injection, EGR, and air handling options (Hyundai, IQPC Gasoline 

Emissions Conference, 2012; Mercedes, Vienna Motorsymposium, 2013; AVL CTI Emissions 

Conference, Detroit, May 2011), and gasoline particulate filters. All of these options will be on 

vehicles in Europe in 2017. 

At the very least, EPA should set a 1 mg/mile standard, and subject it to a technology review. 

The public health benefits will be realized by California and Europe (and later, Japan and China) 

when engine technology is available, and measurement technology will meet the need. Without 

doing this, it is conceivable the majority of Americans will have particulate emissions on some 

vehicles in 2025 that will be more than three times higher than those in California, Europe, 

Japan, and China. 

Environmental Defense Fund (EDF)

EDF applauds the Agency for proposing a 3 mg/mi FTP PM standard for light-duty vehicles to 

“ensure that all new vehicles perform at the level already being achieved by well-designed Tier 2 

emission control technologies.” EPA estimates that PM2.5 emissions will be reduced by an 

estimated 7,500 tons annually in 2030 as a result of these proposed tailpipe standards. EDF 

agrees that it is important to lock in the lower PM emissions rates already being achieved by Tier 

2 vehicles. Moreover, the standard will help prevent any backsliding that could occur as 

manufacturers move toward low carbon technologies to meet increasing greenhouse gas and fuel 

economy standards. 
Chapter 4: Proposed Vehicle Emissions Program

4-34

We also strongly urge the Agency to finalize a more protective PM standard of 1 mg/mi 

beginning in 2025. The more stringent standard is technically feasible and would provide even 

greater human health protections from harmful PM emissions. California has adopted a 1 mg/mi 

standard to begin in 2025. 

A 1 mg/mi FTP PM Standard is Technologically Feasible by 2025. In the preamble, EPA states 

that the “FTP PM standards that we are proposing are the most stringent technically feasible 

standards within the implementation timeframe of this proposal.” However, the Agency does not 

explain why a 1 mg/mi FTP PM standard, as finalized in LEV III, is not technically feasible. The 

Agency only states that more research is needed on PM measurement methods. Nonetheless, 

EDF believes that a 1 mg/mi standard is technically feasible beginning in 2025, as evidenced by 

available technology and many Tier 2 vehicles already achieving such a low emission rate. 

As evidenced by EPA and CARB testing, Tier 2 vehicles on the road today are already 

achieving PM emissions levels at 1 mg/mi or lower. As described in the RIA, EPA conducted a 

test program to measure PM emissions from a variety of Tier 2 light-duty vehicles to help 

establish the feasibility of Tier 3 PM standards. The test program included 17 late model year 

vehicles that represented a significant volume of annual light-duty sales and included vehicles 

that ranged from small cars to trucks, as well as four vehicles with GDI engines. The results of 

the FTP emissions tests found that all but one of the non-GDI vehicles had PM emissions under 

1 mg/mi. And of those, all but one had PM emissions under 0.5 mg/mi. The results of EPA’s 

own tests confirm that existing Tier 2 non-GDI vehicles are already meeting PM emissions levels 

well below the proposed 3 mg/mi standard and all but one are well below a 1 mg/mi PM 

standard. Moreover, these are Tier 2 vehicles on the road today, and a 1 mg/mi PM standard 

would not begin for another 12 years, giving manufacturers ample time to ensure all new 

vehicles can achieve that low emission rate. 

While the GDI engines in EPA’s tests had higher levels of PM, there is ample evidence that GDI 

engines and other low carbon engine technologies needed to meet the most stringent GHG and 

fuel economy standards can also achieve a 1 mg/mi PM standard (135). GDI engines achieve 

greater efficiency by mimicking a diesel engine, and therefore can have PM emissions close to 

those from a conventional diesel engine (one without a DPF). Indeed, all of the Tier 2 GDI 

vehicles tested by EPA had PM emissions over 2 mg/mi, with the highest result at just over 7 

mg/mi. However, according to CARB, “[c]ar makers who choose to pursue gasoline-fueled, CO2 

friendlier GDI internal combustion engines for their future vehicles will have two principal 

technical solutions for further reduction of PM mass emissions” – optimized fuel-injection 

systems and gasoline particulate filters (GPFs). Recent research by the Manufacturers of 

Emission Controls Association (MECA) and Environment Canada found that GPFs can bring 

GDI PM emissions down to levels in line with, or below, those of a typical port fuel injection 

engine. 

Moreover, CARB estimates that the “expected trend is for new GDI vehicles to move towards 

spray-guided GDI engines” and therefore, “compliance with the proposed [LEV III] PM 

standards is not expected to impose a cost increase to vehicle manufacturers’ (138). 
Tier 3 Summary and Analysis of Comments

4-35

EPA and CARB test results, combined with the evidence that gasoline particulate filters are 

capable of reducing GDI engine PM emissions in line with conventional gasoline engines, 

indicate that a 1 mg/mi PM standard is technically feasible by 2025. Therefore, we urge the 

Agency to finalize the more protective standard that would reduce the health burden on all 

Americans. 

EPA has Ample Time to Finalize a Testing Method for a 1 mg/mi PM Standard. The Agency 

states in the preamble that it is not considering a 1 mg/mi standard because of the need for 

“continuing PM measurement method development.” While we agree with EPA that additional 

research and development is needed to reliably measure a 1 mg/mi PM standard, there is ample 

lead-time for such development, and the Agency should not delay the technically feasible, more 

health-protective 1 mg/mi standard for this reason. 

The current method for measuring vehicle and engine PM emissions is determining the mass of 

the PM emissions. In the past, this approach was quite effective because of the large amounts of 

PM emitted by most vehicles. However, as diesel and gasoline vehicles standards become more 

protective, accurately measuring the PM mass becomes more difficult. Over the years, EPA has 

continued to make improvements to its PM mass test methods. These improvements have been 

reflected most recently in the heavy-duty GHG final rule in 2011 and this Tier 3 proposal for 

measuring the proposed 3 mg/mi PM standard. At the same time, a consortium of government 

and industry representatives are currently conducting further research on how to best measure 

PM emissions of 1 mg/mi and lower, including further improvements to PM mass test methods 

as well as new solid particle counting methods, like those used in Europe. California’s LEV III 

rulemaking documents have an extensive description of the advancements made to both 

procedures as of 2012, and indicate that significant progress has already been made in 

developing accurate and reliable measurement techniques for a 1 mg/mi standard. In addition, 

more current data and information about advancements in test procedures were presented at 

recent conferences, including the SAE Congress and Coordinating Research Council Real World 

Emissions Workshop. It is clear that EPA, CARB, and other government and industry members 

are well on their way to developing a reliable test method for more protective standards. And 

with an additional decade before the 1 mg/mi standards would take effect, the Agency has more 

than sufficient time to finalize the most effective and appropriate test method and procedure. 

EDF strongly urges the Agency to finalize the technically feasible PM standard of 1 mg/mi 

beginning in 2025. 

Ferrari

Ferrari considers the proposed...PM standards feasible in 2021 MY. We therefore support this 

aspect of EPA’s proposed rule. 

International Council on Clean Transportation (ICCT)

The ICCT recommends that EPA harmonize with both the CARB 1 mg/mile particulate mass 

standard starting with 2025 and the European particulate number standards. Currently, both 

requirements are hindered by the lack of measurement precision, but continuing research into 

particulate measurement should resolve these issues in the future. 
Chapter 4: Proposed Vehicle Emissions Program

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The FTP supports the proposed FTP particulate standards. These would largely harmonize 

EPA’s requirements with CARB’s. 

One key difference between the Tier 3 proposal and the LEV III rule is that under LEV III, 

automakers must meet a tailpipe emission standard of 1 mg/mi beginning in 2025. Instead, the 

Tier 3 proposal extends only to model year 2023, citing concerns expressed in the CA LEV III 

rulemaking with regard to the state of PM measurement capability to enable testing and 

compliance with a 1 mg/mi standard.. The ICCT strongly recommends that EPA harmonize with 

the LEV III particulate standards beginning in 2025. This will allow plenty of time to develop 

more accurate particulate measurement methods. 

A notable omission from the proposed particulate standards is a particle number limit standard, 

similar to already adopted requirements in Europe. Although the proposal cites the 2010 US EPA 

Integrated Risk Assessment for Particulate Matter, which highlights evidence of a causal 

association between PN exposure and adverse health impacts, the document notes a desire for 

further research to find more robust associations between PN exposure and health impacts. The 

ICCT strongly encourages EPA to investigate harmonization with the European particulate 

number standards in the future. California is likely to pursue particle number measurement 

methods to ensure compliance with 1 mg/mi, which carries the possibility of a transition to a 

particle number limit in future rulemakings. 

Manufacturers of Emission Controls Association (MECA)

MECA strongly supported and agreed with ARB’s decision to include a 1 mg/mile particle 

matter standard for light-duty vehicles over the FTP test cycle in their LEV III requirements. In 

the Tier 3 proposal, EPA proposed only to harmonize with the LEV III 3 mg/mile FTP PM 

standard and not propose a 1 mg/mile FTP PM standard. The 2012 decision by the European 

Commission to establish a particle number emission standard for light-duty vehicles powered by 

gasoline direct injection (GDI) engines as a part of their upcoming Euro 6 light-duty emission 

standards provides a more stringent particle emission limit for these GDI vehicles in the same 

time frame as the Tier 3/LEV III 3 mg/mile PM standard (proposed phase-in for the Tier 3, 3 

mg/mile PM standard starts in 2017 and is fully phased-in with the 2021 model year; 

implementation of the Euro 6 GDI particle number limit of 6 X 1011 particles/km [equivalent to 

the Euro 5 light-duty diesel particle number limit], measured using the European PMP particle 

measurement protocol, begins in September 2017; see: 

ec.europa.eu/enterprise/sectors/automotive/documents/directives/motor-vehicles/index_en.htm). 

This European light-duty GDI particle number limit will cause auto manufacturers to introduce 

cleaner technologies, such as advanced fuel injection systems and/or gasoline particulate filters, 

to comply with the European Euro 6 GDI particle number limit. Auto manufacturers are already 

working to bring forward early introductions of these ultra-low PM, Euro 6-compliant gasoline 

engines to the European market in the coming 12 to 18 months (European member states are 

permitted to introduce tax incentives for early introductions of Euro 6 vehicles prior to the first 

implementation dates of September 2014 for new models and September 2015 for all passenger 

car models). Nearly all auto manufacturers that sell into the European market are working with 

MECA members on potential applications of particulate filters on gasoline direct injection 

vehicles. 
Tier 3 Summary and Analysis of Comments

4-37

Gasoline particulate filters (GPFs) are based on the same, wall-flow ceramic filters that have 

been successfully applied on millions of light-duty and heavy-duty diesel vehicles in Europe and 

the U.S. for more than 10 years. The performance and application of these gasoline particulate 

filters has been highlighted in a number of recent technical publications in both the U.S. and 

Europe (e.g., SAE paper nos. 2010-01-0365, 2011-01-0814, and 2013-01-0836; SAE paper no. 

2013-01-0527 authored by Environment Canada and MECA). Like diesel particulate filters, 

gasoline particulate filters are capable of reducing particle emissions by more than 85% over a 

wide range of particle sizes, including high capture efficiencies for ultra-fine particulates. The 

application of a GPF on a four-cylinder gasoline direct injection vehicle is expected to cost 

approximately $100-120 (see ICCT’s GPF cost estimate available here: 

www.theicct.org/estimated-cost-gasoline-particulate-filters), making this emission control 

technology a cost-effective solution for reducing particulate emissions from future gasoline 

vehicles. When these filters are properly designed, the impact of a GPF installation on the 

backpressure and fuel-efficiency of the vehicle is expected to be minimal. 

EPA needs to make sure that these same ultra-low PM, Euro 6 GDI engine/emission 

technologies are also utilized in the U.S. To that end, MECA believes that it is important for 

EPA, at a minimum, to harmonize with ARB’s LEV III, 1 mg/mile light-duty vehicle PM FTP 

standard to maximize the public health benefits associated with reducing public exposure to 

particulate emissions from future light-duty vehicles. Some consideration should also be given to 

aligning with the European Euro 5/Euro 6 diesel/GDI particle number limit, especially if EPA 

and ARB believe that there are measurement issues with a 1 mg/mile PM standard. Based on 

information presented by ARB at the 2013 CRC On-Road Vehicle Emissions Workshop held in 

San Diego in April 2013 and presented to MECA in May 2013, ARB believes that there is a 

pathway to measuring PM emissions at levels below 1 mg/mile. ARB has published a revised 

PM mass measurement protocol that is part of their pathway to measuring very low PM mass 

levels from the exhaust of a vehicle (see ARB test method MLD 145 available at: 

www.arb.ca.gov/testmeth/slb/exhaust.htm). Ford researchers have also developed a correlation 

between particle number measurements and particle mass that can provide an alternative 

pathway to measuring very low PM mass levels (see M. Matti Mariq and Ning Xu, Aerosol 

Science 35 (2004), pp. 1251-1274). ARB adopted their 1 mg/mile PM standard to provide 

additional public health protection to exposure to particulate emissions from vehicle emissions 

and EPA needs to follow California’s lead in harmonizing with this very tight PM standard. EPA 

and ARB need to continue to work together and reach agreement on measurement protocols that 

are acceptable for use with a 1 mg/mile FTP PM standard. [EPA-HQ-OAR-2011-0135-4675-A2, 

p. 4] Finally, MECA would like to reiterate our strong support for EPA harmonizing with 

ARB’s LEV III 1 mg/mile FTP PM standard. In July 2013 MECA released a new report on 

ultrafine particulate (UFP) emissions entitled, “Ultrafine Particulate Matter and the Benefits of 

Reducing Particle Numbers in the United States.” The report summarizes the current 

understanding of the potential adverse health impacts of UFPs; outlines the various control 

strategies and technologies that can be used to meet current and upcoming U.S. EPA and 

California ARB emission standards (including LEV III and EPA’s proposed Tier 3 standards); 

and documents the success story of using diesel particulate filters (DPFs) to meet and exceed 

U.S. and European emission standards. Notably, the report highlights a correlation between 

particle number (PN) and PM that can be used in conjunction with PM-based health data to 

estimate the health benefits of reducing particle number emissions, and indicates that a PN 
Chapter 4: Proposed Vehicle Emissions Program

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measurement may offer a more robust unit for determining compliance at very low PM mass 

levels. In addition, the report quantifies the health benefits of the additional emission reductions 

that are realized when DPFs or gasoline particulate filters (GPFs) are used compared to only 

engine-based strategies. With respect to light-duty vehicles, the report echoes many of the 

comments made by MECA with respect to the expected dominant use of GDI engines in the U.S. 

because of their improved fuel economy versus port injected gasoline engines, the higher particle 

mass and number emissions of GDI engines relative to port injected engines, and the 

recommendation that EPA follow California’s lead in including a 1 mg/mile PM FTP limit in its 

final Tier 3 standards. Gasoline particulate filters are a cost effective emission control technology 

option for meeting a 1 mg/mile FTP PM standard, and GPFs are expected to be introduced in 

Europe in the near future on some GDI models to meet the Euro 6 GDI PN limit of 6 X 1011 

particles/km. As discussed in this report, compliance at the 1 mg/mile PM level provides 

significant additional health benefits beyond the benefits included by EPA in their Tier 3 

proposal. The full MECA report on ultrafine particulates is available on MECA’s public website, 

www.meca.org, under Resources >> Reports. It is important for the United States to continue to 

set the bar on light-duty vehicle emission standards in order to encourage the development and 

use of best available control technologies for light-duty vehicles. EPA has a long history of 

setting technology-forcing vehicle standards based on the public health benefits they provide and 

this leadership needs to continue with respect to light-duty vehicle particle emission standards. 

In addition, MECA asks EPA to harmonize with ARB’s 1 mg/mile FTP PM standard and to set 

tighter PM limits for the US06 test cycle. 

Natural Resources Defense Council (NRDC)

EPA should establish a process to tighten particulate matter standards and incorporate particulate 

matter number into future standards. 

EPA’s proposed particulate matter (PM) Federal Test Procedure (FTP) standard of 3 mg/mi is 

less health-protective than a 1 mg/mi standard, which the California Air Resources Board 

(CARB) recently adopted. EPA did not adopt a 1 mg/mi standard because the agency believes 

that equipment that can reliably and consistently measure PM levels at and below the standard 

needs further development. However, because CARB has set a 1 mg/mi standard such equipment 

will exist by at least model year 2025. 

EPA should establish a process with CARB to assess the development of needed measurement 

technologies. If the joint agency assessment shows that sufficient measurement technologies are 

feasible, EPA should tighten the PM FTP standard to be at least as stringent as California’s with 

regard to standard levels and phase-in schedules. 

EPA should also evaluate the use of particle number as an additional basis for future PM 

standards, especially to set standards that will reduce ultrafine particle pollution. As history has 

shown with PM10 and then PM2.5 studies, attention to smaller and smaller particles has been 

critical to protecting human health. Particle number measurements may serve to bolster 

verification of controls of very low masses of fine particles (1-3 micrometers) but also become 

the basis for control of ultrafine particles (<1 micrometer). 
Tier 3 Summary and Analysis of Comments

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EPA acknowledges the potential significant health threat from ultrafines, stating that the 

agency’s Integrated Science Assessment for Particulate Matter “concludes that there is 

suggestive evidence of a causal relationship between short-term exposures and cardiovascular 

effects, such as changes in heart rhythm and blood vessel function. It also concludes that there is 

suggestive evidence of association between short-term exposure to ultrafine particles and 

respiratory effects. Data are inadequate to draw conclusions regarding the health effects 

associated with long-term exposure to ultrafine particles”. 

In its review of measurement and control technologies for tighter standards targeting PM2.5, 

EPA should also be evaluating methods to count and control ultrafine particles in future 

standards. 

Northeast States for Coordinated Air Use Management (NESCAUM)

NESCAUM strongly supports the proposed PM standard of 3 mg/mi for all light-duty vehicles, 

light-duty trucks, and medium-duty passenger vehicles for all model years through 2024. 

However, we feel that the standard should be phased down to 1 mg/mi from 2025 to 2028, 

consistent with the requirements of the California LEV III program. We note that encouraging 

progress is being made with respect to reliability of advanced PM measurement techniques, and 

we share CARB’s view that lead time for the 1 mg/mi phase-in is sufficient for appropriate 

measurement techniques to be perfected and validated. We urge EPA to fully harmonize its PM 

standards with CARB’s and to work with CARB to monitor and support continued progress in 

the development of PM measurement techniques. 

Sierra Club, Clean Air Watch, Respiratory Health Association

Fine particulate matter is recognized as extremely hazardous to health, causing lung disease and 

contributing to premature death. The proposed standards seek to reduce emissions of particulate 

matter by proposing a FTP PM certification standard of 3 mg/mi for all model years. The 

proposed SFTP PM certification standard is much higher, either 10 mg/mi or 20 mg/mi, 

depending on the vehicle. 

It is important to note that as part of their Low Emission Vehicle III (LEV 3) standards, the 

California Air Resources Board is proposing lower certification standards and will be phasing in 

a 1 mg/mi FTP standard beginning in MY 2025. 

We urge EPA to coordinate with CARB to determine how to measure ultra-fine particles and to 

consider harmonizing PM standards with those set by CARB in LEV 3. 

Union of Concerned Scientists (UCS)

Particulate Matter Emissions Standard: EPA should harmonize with the California Air Resources 

Board’s (CARB’s) Low Emission Vehicle III (LEV III) standard for particulate matter 

emissions. 

Particulate matter (PM) can travel deep into the lungs and harm human health. Many scientific 

studies have linked exposure to PM with respiratory ailments, chronic bronchitis, asthma attacks, 
Chapter 4: Proposed Vehicle Emissions Program

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heart attacks and premature death, particularly within sensitive populations. Much progress has 

been made in the last decade to limit PM emissions, but more must be done. 

The Union of Concerned Scientists supported CARB’s decision to issue a 1 mg/mile standard for 

light duty vehicles in its Low Emission Vehicle III (LEV III) program and urges EPA to set the 

most stringent PM exhaust emission standard possible as part of this rulemaking. This can most 

easily be accomplished by working with CARB on its development of measurement protocols in 

order to harmonize the Tier 3 program with LEV III. 

Additionally, EPA should strongly consider the inclusion of a particulate matter number limit in 

addition to the PM mass limit for exhaust emissions. The European Commission has recently 

adopted particulate matter number limits in order to address technology adoption that has 

resulted in low PM mass but high PM numbers due to an increase in the ultrafine (<100 nm) PM 

emissions. Adopting a PM number limit (in coordination with CARB) will decrease harmful 

emissions and also result in a standard that is easier to measure. A well-crafted PM number limit 

will ensure the continued protection of public health by limiting exposure to particulate 

emissions and driving advancements in vehicle and emission control technologies. 

Our Response:

Most commenters were generally supportive of the proposed 3 mg/mi FTP PM standard. 

CARB commented that they agree with EPA that these standards are readily achievable with no 

additional technology or hardware. In addition, several commenters, including CARB and 

several NGOs and auto industry suppliers, supported a more stringent standard of 1 mg/mi, 

which the California LEV III program phases in beginning in MY 2025. Some commenters

agree with EPA that additional research and development is needed to reliably measure a 1 

mg/mi PM standard, but believe that there is ample lead time for such development. Another 

commented that, currently, both a 1 mg/mi US06 standard and a potential particle number (PN) 

requirement are hindered by the lack of measurement precision, but they believe that continuing 

research into particulate measurement should resolve these issues in the future. After careful 

consideration of these comments and information available at this time, we continue to believe 

that the PM standards that we are finalizing for the federal Tier 3 program are the most stringent 

technically feasible standards within the implementation timeframe of this rule. (See Chapter

1.5.1 of the RIA describing EPA testing and PM emissions results.) 

We will continue to work closely with CARB in this area. Specifically, our agencies will 

continue our parallel evaluations of how improved gravimetric PM measurement methods can 

reduce PM mass measurement variability at very low PM levels and how this relates to the 

evolving technological capabilities of automakers to reach very low PM levels with sufficient 

compliance margins. Also, as suggested by several commenters, EPA will continue to follow 

research on the association between particle number (PN) and health effects and into the accurate 

measurement of PN. Based on our future findings, we will determine whether any future action 

is appropriate. 

PM emissions over the FTP are generally attributed to cold-start operation, when PM 

formation from combustion of the fuel is facilitated by the operating conditions, including a cold 
Tier 3 Summary and Analysis of Comments

4-41

combustion chamber and fuel enrichment. During cold-start operation, PM control is less 

effective, especially the oxidation by the catalytic converter of semi-volatile organic compounds 

from the lubricating oil. We believe that for vehicles that are not already at the Tier 3 levels, the 

new standards can be achieved with improvements to the fuel controls during the cold start, 

without the need for any new technology or hardware. We also expect that manufacturers will 

pay close attention to maintaining low PM emissions during the implementation of newer 

technologies like gasoline direct injection (GDI) and turbocharged engines. Improvements in 

cold-start exhaust catalyst performance for NMOG+NOx control will also reduce emissions of 

semi-volatile organic PM. For these reasons, cold start PM levels are relatively independent of 

vehicle application and therefore we are finalizing a single FTP PM standard for all light-duty 

vehicles, as proposed. 

The Alliance and Global Automakers support fleet-average standards for PM, instead of 

the proposed per-vehicle standards. We do not believe that fleet average standards are 

appropriate in the case of FTP (and SFTP/US06 PM) because the purpose of the form and level 

of the standards (i.e., per-vehicle versus fleet-average) is different than that of the NMOG+NOx 

standards. For the NMOG+NOx standards, we designed the declining standards to require 

increasing technological progress and gradually improving emissions. For the PM standards, 

many or most manufacturers are already meeting the 3 mg/mi standard with well-performing 

vehicles, and our intent is to bring all other vehicles to the same PM performance. An averaging 

system in this context would not be appropriate, and possibly counterproductive, since fleet 

averaging could allow some or all of the higher-emitting current vehicles to remain at those 

unnecessarily high levels. For these reasons, we are finalizing the per-vehicle form of the FTP 

PM standards.

CARB commented that we should require that a manufacturer that certifies its vehicles to 

the proposed alternative phase-in schedule still meet the requirement that 100 percent of those 

vehicles meet the applicable PM standards in the 2021 model year. The proposed Tier 3 

alternative phase-in schedule includes MY 2021 as the final year when a manufacturer could 

have the flexibility of not meeting the 100 percent target if they outperform the targets in 

MY2017 through 2020. However, we believe that including MY2021 in the alternative phase-in 

schedule provides a reasonable amount of time with which to achieve compliance. We do not 

believe that the duration of the phase-in will negatively impact the PM emission reductions of 

the overall program, because it will require manufacturers to exceed the obligations that would 

have otherwise applied under the primary phase-in in an earlier model year. We are requiring 

that manufacturers meet the 100 percent compliance requirement in MY2022.

4.1.2.6. Specific Comments on US06 PM Standards

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)
Chapter 4: Proposed Vehicle Emissions Program

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The red text shows the discrepancy between the EPA Tier 3 and the ARB LEV III regulations. 

We appreciate that EPA recognizes this disconnect between the regulations and allows 

manufacturers to count vehicles in the 6,000-8,500 pounds GVWR weight class toward 

compliance with the phase-in percentage (i.e., numerator only) in MY 2017 (we would note what 

appears to be a typo in §86-1811-17(b)(6)(i)). However, this would not benefit manufacturers 

with a small volume of vehicles in the weight class. To harmonize with LEV III, we recommend 

adding an option for manufacturers to comply with the MY 2017 phase in by producing 10 

percent of their 0-8,500 pounds GVWR fleet to the revised PM Standard. 

Recommendation: We recommend the following changes (including a correction to the typo 

mentioned above) to §86-1811-17(b)(6)(i): 

‘Tier 3 FTP standard for PM must also meet the Tier 3 US06 standard for PM. In model year 

2017, the phase-in requirement does not applyies only for to vehicles at or below above 6,000 

pounds GVWR; however, if you certify these vehicles to the Tier 3 PM standards in the model 

year 2017, you may count those projected U.S. sales toward your calculation for meeting the 

phase-in percentage for that year (numerator only). Alternatively, you may comply in the model 

year 2017 meeting the FTP and the US06 PM standards with 10 percent of your projected 

nationwide sales of all vehicles (including those greater than 6,000 pounds GVWR).’

The NPRM proposes to adopt new US06 PM standards to control PM emissions under the high 

speeds and loads encountered on the US06 cycle. The standards proposed harmonize with the 

LEV III US06 PM standards of 10 mg/mile for vehicles <6,000 pounds GVWR, and 20 mg/mile 

for vehicles >6,000 pounds GVWR. In §IV(A)(4)(b) of the Preamble to the Tier 3 NPRM, EPA 

asks for comment on the proposed Tier 3 US06 PM standards, including whether EPA should 

adopt a standard of 10 mg/mile for all vehicles (both less than and greater than 6,000 pounds 

GVWR). 

First, we would note that light-duty vehicles and light-duty trucks are a very small fraction of 

PM emissions, accounting for less than two percent of total PM10 emissions and less than four 

percent of PM2.5 emissions. The other 98 and 96 percent of PM emissions, respectively, come 

from sources such as cooking, farming operations, construction and demolition, etc. 

The US06 PM Standard is an entirely new test for which the industry and the agencies are still 

gathering and analyzing the emissions data. Further complicating the standards are the likely 

introduction of new technologies to meet the GHG standards. Given this, we are concerned with 

the technical feasibility of achieving even the proposed SFTP US06 PM standard of 10 mg/mile 

for passenger cars and trucks under 6,000 pounds GVWR and 20 mg/mile for light-duty trucks 

over 6,000 pounds GVWR. In particular, technologies needed to meet the GHG requirements 

may conflict with the US06 PM standards. Future low-powered/downsized technologies and 

range extenders needed to meet the GHG requirements, for example, may not be able to comply

with the proposed PM standards. 

Another point of concern is that the PM standards are flat standards that all vehicles must meet, 

as compared to fleet average standards that are proposed for NMOG+NOx compliance. Thus the 

risk that a particular type of technology would be precluded by the PM standards is increased 
Tier 3 Summary and Analysis of Comments

4-43

because such technology cannot be certified to a higher bin and offset by a different technology 

certified to a lower bin. 

Moreover, requiring full-size pickups and SUVs that make up the over 6,000 pounds GVWR 

category to meet the same flat standard that smaller and lighter vehicles in the under 6,000 

pounds GVWR category must meet is effectively making the full-size pickups and SUVs meet a 

more stringent standard, given the higher engine throughput associated with these larger, heavier 

vehicles. 

It is also worth noting that the PM standards begin at a time when manufacturers enter the eighth 

year of the most stringent GHG standards in history, when the number of ZEVs and PHEVs 

jumps considerably in California and the Section 177 states, and while reducing exhaust 

emissions by 75 percent on both the FTP and SFTP and phasing in zero evaporative emission 

standards on all vehicles. 

Recommendation: Taking all of this into consideration, industry does not oppose adopting the 

proposed US06 PM standards that will harmonize the LEV III and Tier 3 standards. However, 

we oppose adoption of 10 mg/mile PM standard on the US06 for all light-duty trucks over 6,000 

pounds GVWR. We are concerned that such standards are not feasible given the technological 

changes necessary to meet all of the other emission requirements manufacturers must meet in the 

exact same timeframe. Moreover, such standards are not warranted. 

American Lung Association

We believe the Supplemental FTP PM emissions standards are not sufficiently aggressive and 

are, in reality, a non-standard. EPA has proposed a Supplemental FTP PM emissions standard of 

10 mg/mile which would allow far more PM emissions than existing vehicles currently emit. 

According to a memorandum describing EPA’s own testing, no vehicles either above or below 

6,000 pounds gross vehicle weight rating emitted more than 3.5 mg/mile and most were well 

below that level. We urge EPA to set the tightest feasible Supplemental FTP PM emissions 

standards, which would be no greater than 4 mg/mile. 

California Air Resources Board (CARB)

Comment 3 - Set lower PM standards Over the Supplemental Federal Test Procedure — US06 

Cycle: The proposed Tier 3 program includes US06 PM standards of 10 mg/mi for lighter 

vehicles and 20 mg/mi for heavier vehicles. Based on recent PM emission data generated by both 

CARB and U.S. EPA test programs, CARB believes that a more stringent US06 PM standard of 

4 mg/mi applicable to both vehicle categories is feasible. The following is a summary of these 

test programs as well as CARB’s rationale for the recommendation. 

Prior to California’s LEV Ill rulemaking, eight California LEV II-certified light-duty vehicles, 

which included five gasoline direct injection vehicles and three port fuel injection vehicles, were 

tested for PM emissions over the US06 cycle in CARB’s Haagen-Smit laboratory. Measured PM 

emissions from seven out of eight vehicles were below 3 mg/mi, including all five gasoline direct 

injection vehicles. A gasoline medium-duty passenger vehicle (gross vehicle weight rating 
Chapter 4: Proposed Vehicle Emissions Program

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between 8,501-10,000 Ibs) with an odometer reading of approximately 50,000 miles was also 

tested and achieved a US06 PM emission value of 0.8 mg/mi, comparable to those measured 

from the lightduty test vehicles. One particular light-duty test vehicle had PM emissions in 

excess of 3 mg/mi, but CARB suspects that because the vehicle was not designed or certified to a 

stringent US06 PM standard, the calibration strategy may not have been optimized for PM 

control over the US06 and further refinement to the calibration would likely address the issue 

including minimizing any enrichment events that directionally increase emissions. 

Recently, U.S. EPA shared PM emission data from its full useful life program with CARB. The 

primary objective of the full useful life program was to establish the feasibility of Tier 3 PM 

standards at vehicle full useful life and investigate the contribution of lubricating oil to PM 

emissions in Tier 2 vehicles. More than two dozen passenger cars and light-duty trucks were 

tested for PM emissions on the FTP and US06 cycles. Initial results showed high PM emissions 

in excess of 40 mg/mi from some of the vehicles over the US06 cycle. U.S. EPA later 

determined that silicone contamination from the use of silicone exhaust transfer tubes in the 

emission sampling system was a major contributor to the measured PM mass emissions, 

especially on test cycles that generate high exhaust temperatures such as the US06 cycle. As a 

result, U.S. EPA re-tested a dozen vehicles and the new data show that all twelve vehicles, 

including a suspected oil burner, emit at levels less than 4 mg/mi PM on the US06’ cycle. 

In response to U.S. EPA’s recent US06 testing and the discovery of the silicone contamination 

issue, CARB has initiated a test program to further investigate PM emissions on the US06 cycle 

and determine the feasibility of a more stringent standard: The test program aims to gather US06 

PM emission data on both current and future engine technologies, such as port fuel injection, 

gasoline direct injection, turbocharging, and engine downsizing, and the test vehicles are being 

selected accordingly. While the test program is on-going and vehicles are still being tested, thus 

far, US06 PM data have been collected for eight port fuel injection vehicles, including one lightduty truck and two gasoline direct injection vehicles. PM emissions over the US06 cycle from 

seven out of the ten vehicles were measured below 1 mg/mi while nine out of ten were measured 

below 4 mg/mi. The one vehicle that had PM emissions above 4 mg/mi also showed FTP 

emissions that exceeded the LEV II FTP PM standard, so it is likely that the vehicle was not 

operating within design specifications at the time of testing. 

While the findings of the above test programs clearly show that current LEV II vehicles which 

are not subject to PM standards under the LEV II SFTP program, are capable of complying with 

a 4 mg/mi US06 PM standard, there have been some concerns regarding future technologies, 

such as advanced gasoline direct injection and turbocharged, downsized engines. While these 

future technologies are expected increase cylinder pressures and temperatures and possibly the 

need for additional engine temperature control, CARB still believes the 4 mg/mi US06 PM 

standard is feasible. This is because affected Tier 3 vehicles will be equipped with improved PM 

control technologies needed to comply with the 3 mg/mi PM standard on the FTP (in lieu of the 

10 mg/mi PM standard that LEV II vehicles are certified to) and because additional calibration 

opportunities will exist as even today’s LEV II vehicles, which are calibrated without PM control 

considerations over the US06 cycle, generally have emission levels below 4 mg/mi with 

compliance margin. 
Tier 3 Summary and Analysis of Comments

4-45

In summary, while CARB will continue to collect US06 PM emission data on future 

technologies, CARB believes the data currently available sufficiently supports a more stringent 

standard and recommends that U.S. EPA adopt a US06 PM standard of 4 mg/mi in the Tier 3 

program. Additionally, should U.S. EPA adopt a more stringent standard in the final proposal, 

CARB recommends that the corresponding in-use standards also be lowered in accordance with 

any changes to the certification standards. 

Comment 4 — Optional Phase-In Formula for FTP and US06 PM Standards: U.S. EPA is 

proposing to phase-in Tier 3 FTP and US06 PM emission standards beginning with the 2017 

model year with 100 percent compliance required in the 2021 model year. U.S. EPA has also 

proposed an optional alternative phase-in schedule that manufacturers may use to comply with 

the Tier 3 PM emission standards for these model years. This alternative phase-in schedule is 

based on a mathematical equation that provides credits for vehicles certified to the Tier 3 PM 

standards based on the year in which they are certified. Accordingly, vehicles certified to Tier 3 

PM standards in earlier years would be worth more than those certified in later years. This 

alternative phase-in schedule is similar to one CARB adopted for vehicles meeting the LEV III 

PM standards. However, while the LEV Ill regulations explicitly state that 100 percent 

compliance is required at the end of the phase-in period, the proposed Tier 3 regulations do not. 

We believe that in order to maintain the emission benefits of the Tier 3 program, it is necessary 

to add language to the Tier 3 rule to clarify that a manufacturer that certifies its vehicles to this 

alternative phase-in schedule must still meet the requirement that 100 percent of those vehicles 

meet the applicable PM standards in the 2021 model year. 

[See CARB’s public comment document EPA-HQ-OAR-2011-0135-4919-A1, received by the 

docket on October 23, 2013, for two graphics: CARB Light-Duty SFTP Program (PFI Vehicles) 

and CARB Light-Duty SFTP Program (GDI Vehicles)]

Environmental Defense Fund (EDF)

EPA Should Adopt Most Protective US06 PM Standard – Not Based on Vehicle Weight: EPA 

seeks comment on the use of vehicle weight to establish separate US06 PM standards for cars 

and trucks.143 EDF asks the Agency to adopt one protective US06 PM standard for all vehicles 

subject to the Tier 3 program, regardless of weight. [EPA-HQ-OAR-2011-0135-4355-A1, p. 27]

EPA is proposing a US06 PM standard of 10 mg/mi for vehicles at or below 6,000 lbs GVWR 

and a standard of 20 mg/mi for vehicles over 6,000 lbs GVWR. EDF believes both of these 

standards are too lenient and the Agency should adopt a single, more protective standard for all 

vehicles subject to Tier 3. As EPA states in the preamble, “today’s heavier vehicles are already 

achieving PM emission levels well below our proposed 20 mg/mi standard and are 

approximately equivalent to the performance of lighter vehicles.” Indeed, EPA’s data presented 

in the RIA show that all of the vehicles tested, both above and below 6,000 lbs, achieved a US06 

PM emissions result of less than 4 mg/mi. And as illustrated in EPA’s Figure below, similar 

emissions rates were recorded for both light and heavy vehicles, indicating that heavier vehicles 

are capable of meeting the same US06 PM requirements as the lighter vehicles. EPA’s test 

results also indicate that not only can all vehicles, regardless of weight, meet the same standard, 

but that standard can and should be set well below the 10 mg/mi standard proposed by EPA for 
Chapter 4: Proposed Vehicle Emissions Program

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vehicles under 6,000 lbs GVWR. We recommend that EPA finalize a US06 PM standard for all 

vehicles subject to the Tier 3 program of no greater than 4 mg/mi.

Ferrari

Ferrari considers the proposed PM standards feasible in 2021 MY. We therefore support this 

aspect of EPA’s proposed rule. 

Ford Motor Company (Ford)

Consistent with the CA LEV III program, EPA has proposed two separate US06 particulate 

matter (PM) standards for light-duty vehicles: 10 mg/mi for vehicles less than 6,000 pounds 

GVWR, and 20 mg/mi for vehicles over 6,000 pounds GVWR. EPA has asked for comment on 

these standards and also whether a single, 10 mg/mi standard applied to all light-duty vehicle 

(LDV) classes would be more appropriate. Ford agrees with the Alliance comments on this issue 

and strongly opposes the application of a 10 mg/mi standard to vehicles over 6,000 pounds. 

Unlike PM generation on the Federal Test Procedure (FTP) which is typically dominated by the 

“cold-start” portion of the cycle–PM on the US06 is more closely related to the work the vehicle 

is required to perform over the cycle, which naturally increases with vehicle mass. Requiring 

heaver vehicles to meet the same PM limits as lighter vehicles would, in effect, increase the 

stringency of the PM standards for these vehicles at a time when automakers must introduce new 

technologies to meet challenging GHG standards. This increased stringency would be 

disproportionally applied to full-line manufacturers. The higher 20 mg/mi standard will help 

ensure that similar fuel economy / greenhouse gas advances can be applied to both lighter and 

heavier vehicles. US06 PM emissions are also affected by several factors related to the high 

exhaust temperatures characteristic of this drive cycle, including: 1) the need for catalyst 

protection, 2) potential desulfurization of the catalyst, and 3) storage/release artifacts from the 

exhaust and sampling systems. As vehicle size increases, so does the thermal energy in the 

exhaust. Above 6,000 pounds GVWR, this leads to quicker and more extensive heating of the 

catalyst and exhaust system during the US06 cycle that exacerbates these issues relative to 

lighter vehicles. 

Recommendation: Ford recommends that EPA adopt the light-duty US06 PM standards as 

proposed in the Tier 3 NRPM, which specifies a 20 mg/mi standard for LDVs above 6,000 lbs 

GVWR. 

International Council on Clean Transportation (ICCT)

As cold starts have a relatively small impact on particulate emissions, the same times two factor 

found for SFTP NMHC+NOx emissions should also be applied to particulate emissions. This 

means that the SFTP PM standard should be set at no more than 6 mg/mi. 

Further, there is no reason why light-duty vehicles over 6,000 GVWR should be held to less 

stringent particulate standards. This violates the premise established with the Tier 2 emission 

standards that all light-duty vehicles should be held to the same emission standards. It is 
Tier 3 Summary and Analysis of Comments

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especially important that GVWR not be used to discriminate between different standards, as 

GVWR is easily gamed. 

The problem is far worse for particulate matter. As the proposed SFTP particulate standard is 

3.3 times larger for light vehicles and 6.7 times larger for heavy duties -- heavier vehicles than

the FTP particulate standard.

Supplemental comments from ICCT:

The International Council on Clean Transportation (hereafter, “ICCT”) is submitting 

supplemental comments specifically on SFTP PM (particulate matter) standards. Our primary 

comments were submitted to the docket with our letter of July 1, 2013 and the information in that 

submission will not be repeated here. 

In our initial submission, the ICCT discussed the reasons why the proposed SFTP standards are 

too lenient and will not be effective. Setting the SFTP standards properly is especially important 

for diesel engines, as diesel emission control hardware requirements are largely set by the high 

load conditions on the SFTP. The ICCT recommended that the SFTP particulate standards be set 

at no more than 6 mg/mi. 

We are submitting additional comments on SFTP PM standards in response to the recent release 

of test data on US06 PM2.5 emissions by CARB.1 CARB recently tested 11 light-duty vehicles 

and trucks over the US06 and measured PM emissions. Results are presented in Figure 1 and the 

vehicle descriptions are in Table 1.

Seven of the eleven vehicles tested had PM emissions much less than 2 mg/mile. The Camry and 

the Explorer had PM emissions between 2 and 4 mg/mile. Only the Optima and the Juke 

exceeded 4 mg/mile. 

Both the Juke and the Optima had GDI (gasoline direct fuel injection) engines. The literature has 

suggested that GDI engines with poor combustion design and wall-guided fuel injection could 

have higher PM emissions. However, the literature has also suggested that GDI engines with 

good design and spray-guided fuel injection could have low PM emissions. This is supported by 

the test results on the Ford Fusion, which also has GDI and has PM emissions of just over 1 

mg/mile. 

In addition, the Juke failed particulate standards on the FTP. This means that this vehicle may 

not have been operating properly or has a poorly designed GDI system. In any case, the fact that 

this vehicle was out of compliance means that the data should not be used when setting the SFTP 

PM standards. 

While only two light duty trucks were tested, their emissions were also reasonably low, 

suggesting that light duty truck standards should be set at the same level as light duty vehicle 

standards. Further, there is no reason why light-duty vehicles over 6,000 GVWR should be held 

to less stringent particulate standards. This violates the premise established with the Tier 2 

emission standards that all light-duty vehicles should be held to the same emission standards. It 
Chapter 4: Proposed Vehicle Emissions Program

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is especially important that GVWR not be used to discriminate between different standards, as 

GVWR is easily gamed. 

Finally, it is extremely important to note that these PM emissions were measured in vehicles with 

existing emission controls. The proposed reductions in FTP PM emissions will require better 

combustion chamber and fuel injection designs, resulting in lower SFTP PM emissions as well. 

In summary, the recent CARB test data completely supports ICCT’s recommendation in our 

initial comments, that the SFTP PM standards should be set at no more than 6 mi/mile. In fact, 

the test data suggests that even 6 mg/mile would be too lenient and too easy to meet. 

Manufacturers of Emission Controls Association (MECA)

With respect to the proposed PM limits for the supplemental FTP test cycles, EPA acknowledged 

that their Tier 3 proposal is flawed by a dataset that included contamination with respect to the 

PM analyses that were done on Tier 2-compliant vehicles. ARB shared with MECA in late May 

2013 some of the revised, corrected Tier 2/LEV II US06 test cycle results. These data support a 

much tighter PM standard for the US06 test cycle than proposed by EPA for Tier 3. MECA 

understands that ARB intends to propose that EPA set a Tier 3 US06 PM limit of approximately 

4 mg/mile for all light-duty vehicles (as opposed to the proposed Tier 3 US06 PM limits that 

depend on vehicle weight) based on the testing they are expected to complete before July 1, 

2013. MECA is supportive of ARB’s Tier 3 comments on this subject and asks that EPA (and 

ARB) set the tightest, feasible US06 PM standard in their final Tier 3 regulation. 

National Association of Clean Air Agencies (NACAA)

US06 PM Standards — For the Supplemental Federal Test Procedure EPA has proposed that the 

standards for PM be met based on the US06 test, which represents aggressive highway driving, 

since the greatest concern regarding PM formation and sensitivity of engine controls is due to 

high-speed, high-load driving conditions. In particular, the agency has proposed a US06 PM 

standard of 10 milligrams per mile (mg/mi) for vehicles at or below 6,000 pounds gross vehicle 

weight rating (GVWR) and a standard of 20 mg/mi for heavier light-duty vehicles, to be phased 

in over a five-year period beginning in 2017. However, given EPA data showing that 

manufacturers appear to be controlling PM emissions from heavier light-duty vehicles over 

severe duty cycles, EPA requests comments on whether it should adopt a common US06 

standard of 10 mg/mi for all light-duty vehicles. NACAA has reviewed EPA US06 PM 

emissions test data provided in a March 1, 2013, agency memorandum available in the Tier 3 

rulemaking docket (4). According to the test data shown in Figure 8 (on final US06 PM emission 

results) of that memorandum, it is clear that US06 PM emission results for vehicles under and 

over 6,000 pounds GVRW are far below 10 mg/mi. In fact, no vehicle tested is over 4 mg/mi and 

most are substantially lower. Given the significance for air quality and public health of reducing 

PM emissions, NACAA recommends that EPA adopt US06 PM standards below 10 mg/mi for 

all affected light-duty vehicles — under and over 6,000 pounds GVWR — as supported by the 

agency’s test data. 

Union of Concerned Scientists (UCS)
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Millions of Americans breathe cleaner air as a result of our nation’s clean air laws but serious 

challenges remain. More than 1 in 3 Americans still live in areas where air pollutant levels 

exceed at least one of the health-based National Ambient Air Quality Standards. Passenger 

vehicles remain the second largest emitters of nitrogen oxides (NOx) and volatile organic 

compounds (VOCs) in the U.S. – the primary pollutants that form smog. These vehicles also 

emit more than half of all carbon monoxide pollution and contribute to particulate matter 

emissions. It is therefore essential that the Tier 3 standards for both PM and NMOG+ NOx be 

sufficiently stringent as to provide quantifiable and real reductions in harmful emissions. 

We urge EPA to consider levels for the SFTP... PM... that are sufficiently stringent to ensure 

that they are suitably protective of human health and the environment. 

Supplemental Federal Test Procedure: EPA should revisit the... particulate matter (PM) exhaust 

emission requirements to ensure that the emission requirements of this test procedure are suitably 

protective of human health and the environment. 

The problem is similar for PM. The SFTP PM standard is more than three times higher than the 

PM FTP standard in 2023 for light duty vehicles and more than six times higher for vehicles with 

a gross vehicle weight rating of more than 6,000 pounds. As CARB explains in its comments 

(10), there were flaws in the data collected during EPA’s useful life testing due to silicon 

contamination resulting in higher PM emissions. Retesting of some of these vehicles, as well as 

additional testing undertaken CARB supports the setting of more a stringent PM standard for the 

US06 test cycle than currently under consideration. 

Our Response:

Comments from stakeholders representing states, including CARB, and several NGOs 

urged EPA to finalize more stringent US06 PM standards than those proposed, in all cases 

advocating for standards below 10 mg/mi for the entire light-duty fleet and in some cases 

advocating for standards below 6 mg/mi. Conversely, auto industry commenters generally 

supported the proposed standards (10 mg/mi and 20 mg/mi for lighter and heavier light duty 

vehicles, respectively. We have concluded that the body of recent data clearly shows that the 

long-term 6 mg/mi US06 PM standard that we are finalizing, is the appropriate level to prevent 

any significant “backsliding” in US06 PM emissions as new vehicles and technologies enter the 

fleet. At the same time, the 6 mg/mi standard provides a reasonable compliance margin -- about 

50% above the average levels of current vehicles, which are averaging about 3 to 4 mg/mi. A 

long-term standard numerically lower than 6 mg/mi would run counter to our intent to bring the 

emissions performance of all vehicles to that already being demonstrated by many vehicles in the 

current light-duty fleet. We believe the long-term US06 PM standard we are finalizing is 

appropriate based on all of the information available at this time and will not hinder introduction 

of new technologies manufacturers may choose for compliance with the other Tier 3 standards or 

other rules. 

The short-term, less-stringent US06 standard of 10 mg/mi (applicable in MYs 2017 and 

2018) responds to automaker concerns about uncertainties stemming from simultaneous 

regulatory requirements and rapidly evolving exhaust and engine technologies in the coming 
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4-50

years. We recognize that vehicle control technologies for both criteria and GHG emissions are 

evolving and will continue to do so, including an expected expansion of gasoline direct injection 

(GDI) technologies (see Section IV.A.5.c of the preamble and the RIA). Also, the transition to 

lower sulfur in-use gasoline required by this rule may create temporary additional challenges in 

consistently achieving lower US06 PM emissions (see Section IV.A.6 of the preamble and in the 

RIA). We believe that most manufacturers will implement similar if not identical emission 

control strategies to comply (or, more often, to continue to comply) with both the 10 mg/mi and 

the 6 mg/mi standards. In so doing, we expect them to use the temporary additional compliance 

margin provided by the 10 mg/mi standard to reduce uncertainties about potential variability in 

performance (in use and, in particular, later in vehicle life) during the early years of developing 

and commercializing their control technologies. 

The 10 mg/mi standard will expire after MY 2018, and the long-term standard of 6 mg/mi 

will take effect. As the implementation of the program continues, we believe a limited degree of 

relief for testing of in-use vehicles is appropriate. Manufacturers commented that because of the 

industry’s general lack of experience with stringent PM standards, especially as the newlydesigned vehicles age, less stringent standards for in-use testing would reduce near-term 

concerns about performance variability early in the program. We agree, and we are finalizing a 

separate standard of 10 mg/mi for in-use vehicle testing for the intermediate years of the 

program, MYs 2019 through MY 2023. This standard is numerically lower than the proposed inuse standards – again because of the availability of improved US06 test data as described above 

– but the purpose of providing an in-use standard remains the same. The in-use standard, in 

conjunction with the short-term 10 mg/mi standard, represents a longer duration of relief than we 

had proposed, again based on comments from the industry about their compliance concerns with 

new US06 standards. For MY 2024 and later, there will be no separate in-use standard and all 

vehicles will need to meet the long-term standard at certification and in use. 

EPA proposed that different US06 PM standards apply to lighter and heavier vehicles. 

The US06 PM test data discussed above also makes clear that the US06 PM performance of 

current vehicles is not closely related to vehicle weight, although the earlier data had indicated 

that this might be the case. Several commenters urged EPA to finalize a single standard for 

vehicles above and below 6,000 lbs GVWR based on the newer data. At the same time, auto 

manufacturers generally supported the proposed vehicle weight distinction, asserting a higher 

degree of uncertainty about the emission performance of their larger vehicles, especially in the 

early years of the program and in light of simultaneous technology challenges. The data clearly 

show that larger vehicles today are generally achieving US06 PM levels very similar to smaller 

vehicles, and well below the proposed standards. We are not finalizing separate US06 standards 

for heavier and lighter vehicles because separate standards are unwarranted based on a review of 

the data. However, we believe that the short-term 10 mg/mi standard, as well as the temporary 

in-use vehicle testing standard, will significantly reduce manufacturer compliance uncertainties 

in the early years of the program for all vehicles, as discussed above. 

As with the FTP PM standards, manufacturers will comply with the US06 PM standards 

with the same increasing minimum percentage of their vehicles. Also, in response to 

manufacturer concerns about the transition to Tier 3, and as with the FTP PM phase-in, we are 

providing the option for a manufacturer to choose to certify 10 percent of its total light-duty 
Tier 3 Summary and Analysis of Comments

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vehicle sales in MY 2017 to the new US06 PM standards, including light-duty vehicles over 

6,000 lbs GVWR.

As discussed in Section IV.A.2.c of the preamble, for LDVs and LDTs more than 6,000 

lbs GVWR and MDPVs, EPA is also providing an alternative phase-in of the US06 PM 

standards

The primary PM percent phase-in schedule for MY 2017 requires 20 percent of vehicles 

6,000 lbs. or less GVWR to comply with the new PM standards. In review of the comments 

regarding the PM phase-in requirements for MY2017, we agree with the commenters that the 

option we proposed may not by itself always apply equitably to manufacturers of different fleet 

mixes. In response to the suggestions, in addition to the primary PM phase-in we are finalizing 

the option that a manufacturer may comply in MY 2017 by meeting the FTP and the US06 PM 

standards with 10 percent of its projected nationwide sales of all vehicles (including those greater 

than 6,000 pounds GVWR). This approach is harmonized with the LEV III PM requirements in 

MY 2017. 

As in their comments on FTP PM standards discussed above, CARB commented that we 

should require that a manufacturer that certifies its vehicles to the proposed alternative phase-in 

schedule still meet the requirement that 100 percent of those vehicles meet the applicable PM 

standards in the 2021 model year. See the response in Chapter 4.1.2.5 of this document. 

Regarding the Alliance/Global comment about per-vehicle vs. fleet average standards for 

PM, see our response in Chapter 4.1.2.5 of this Summary and Analysis of Comments document.

4.1. LD Exhaust Standards

4.1.3. Start Date and Phase-In Schedules and Lead Time

4.1.3.1. Need to Maintain 2017-18 Start Dates

What Commenters Said:

Boulder County Board of Commissioners and Boulder County Board of Health 

Therefore, it is imperative that the federal government take action by December 31, 2013, to 

adopt Tier 3 so it can be implemented with the 2017 model year of vehicles. If not, an entire year 

of benefits will be lost, resulting in serious and adverse impact on human health and welfare. 

Children’s Environmental Health Network (CEHN)

EPA should eliminate the one-year delay of fleet average NMOG+NOx FTP standards phase-in 

for vehicles with GVWR above 6,000 lbs. 

Motor & Equipment Manufacturers Association (MEMA)
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The EPA’s proposal is mindful of other regulatory frameworks and compliance regimes. Efforts 

to harmonize Tier 3 vehicle emission requirements nationwide and to choreograph the timing of 

Tier 3 implementation with the final rules for greenhouse gas (GHG) emissions and corporate 

average fuel economy (CAFE) standards for light-duty vehicles are critical for interconnected 

and highly complex vehicle manufacturing supply chains. Also, EPA’s integrated systems 

approach to vehicles and fuels, combined with the alignment to other parallel regulations, is 

practical and cost-effective. Companies and government entities alike will benefit from the 

resulting outcomes, such as streamlined costs for R&D and production and reduced burden for 

multiple, overlapping testing and compliance protocols. Since the timing of this rule is critical, it 

is important that EPA not delay its completion. If delayed, the benefits of synchronizing the 

timing of the GHG emissions, CAFE standards, and other programs will be lost and may 

negatively impact the states in achieving their respective air quality goals.

MEMA urges EPA to fully consider the public comments, particularly from the vehicle 

manufacturers. In addition, EPA must continue to collaborate with states, like California, and 

other stakeholders to avoid divergent policy pathways and competing regulatory regimes. 

MEMA recommends that the Agency promulgate a final rule by end of 2013 in order to match 

with other regulatory requirements standards affecting MY 2017 vehicles. 

Manufacturers of Emission Controls Association (MECA)

[MECA] ... urges EPA to finalize these proposals by the end of this year. 

Our Response:

As proposed and as discussed in Section IV.A.2.a of the Preamble, the declining fleetaverage NMOG+NOX FTP standards will begin in MY 2017 for light-duty vehicles and lightduty trucks with a GVWR up to and including 6,000 lbs and in MY 2018 for light-duty vehicles 

and light-duty trucks with a GVWR greater than 6,000 lbs and MDPVs. The standards apply to 

the heavier vehicles a year later to facilitate the transition to a 50-state program for all 

manufacturers. During this transition period, there will be two fleet-average NMOG+NOX

standards for each model year, one for LDVs and LDT1s and one for all other LDTs (LDT2s, 

LDT3s, and LDT4s) and for MDPVs that decline essentially linearly from MY 2017 through 

MY 2025. At that point, the two fleet-average standards converge and stabilize for all later 

model years at the same level, 30 mg/mi, which is identical to the LEV III final fleet average.

While the rule is be finalized in 2014 deadline we have maintained the requirement that 

implementation of the Tier 3 standards start in MY 2017. This planned program start retains the 

benefits synchronizing the phase-in of the Tier 3 rule with other related programs.

4.1.3.2. Statutory Concerns About Lead Time for Heavier LD Vehicles and Issues 

With Alternative Phase-In Schedules

What Commenters Said:
Tier 3 Summary and Analysis of Comments

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Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

In several places throughout the regulations, EPA skirts the plain language of the CAA by 

offering two alternatives – one that does not comply with the CAA lead time provisions but 

offers a reasonable requirement, and another that provides the required lead time but is so 

stringent that no reasonable company would ever choose it. The CAA does not authorize this 

approach, nor is EPA following Congress’ clear intent and direction. Moreover, complying with 

the plain language of the CAA would achieve the same level of emissions reduction. While we 

applaud and support EPA’s desire to harmonize with California as expeditiously as possible, it is 

not necessary to violate the CAA in the process. 

The CAA clearly requires EPA to provide four years of lead time for changes to emission 

standards for heavy-duty vehicles, which are defined in CAA § 202(b)(3)(C) as those vehicles 

manufactured primarily for use on public roads that have a gross vehicle weight rating (GVWR) 

of more than 6,000 pounds.(2) Specifically, CAA § 202(a)(3)(C) states, “Any standard 

promulgated or revised under this paragraph and applicable to classes or categories of heavyduty vehicles or engines shall apply for a period of no less than 3 model years beginning no 

earlier than the model year commencing 4 years after such revised standard is promulgated.” (3) 

EPA proposes both a primary path and an alternative path for complying with the FTP and SFTP 

NMOG+NOx standards:

Primary Path – Fleet Average: Under this option, both FTP and SFTP NMOG+NOx standards 

are phased in using a fleet average requirement. The manufacturer can certify vehicles to any of 

a number of specified emission bins, but for each model year, the sales-weighted average 

emissions must meet a fleet average standard that decreases from MY 2017 to MY 2025 for 

vehicles less than 6,000 pounds GVWR, and from MY 2018 to MY 2025 for vehicles over 6,000 

pounds GVWR. 

Alternative Phase-In: Under this option, Tier 3 FTP and SFTP standards under the primary 

option apply for vehicles under 6,000 pounds GVWR in MYs 2017 and 2018, but do not apply 

for over 6,000 pound GVWR vehicles until MY 2019. Starting in MY 2019, 40 percent of all 

vehicles (both less than and greater than 6,000 pounds GVWR) must meet the final FTP and 

SFTP standards; in MY 2020, 70 percent of vehicles must meet the final standards; and in MY 

2021– a full four model years ahead of the primary phase-in option – 100 percent of a 

manufacturer’s fleet must meet the final Tier 3 standards. 

Assuming EPA issues a Tier 3 final rule in late 2013, as planned, MY 2014 already would have 

begun. Therefore, the CAA requires that the regulations applicable to heavy-duty vehicles take 

effect no earlier than the MY 2019 (four years after the MY 2014 would be MY 2018, and the 

next MY would be 2019). Thus, EPA’s proposed primary path for compliance with the FTP and 

SFTP NMOG+NOx Phase-In, which would require manufacturers of heavy-duty vehicles to 

begin complying with the more stringent Tier 3 standards in MY 2018, violates the lead time and 

stability requirement in CAA § 202(a)(3)(C). 
Chapter 4: Proposed Vehicle Emissions Program

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Although the alternative compliance path phase-in for NMOG+NOx does meet the lead time 

requirement, it would require manufacturers to fully comply with the more stringent standards 

four years earlier, imposing significantly more stringent requirements on the manufacturers’

fleet. This presents manufacturers with a Hobson’s choice: either 1) give up the right to four 

years of lead time under the CAA, or 2) assert the right to four years of lead time under the CAA, 

and get punished with more stringent standards as a result. The alternative compliance path is so 

burdensome that no reasonable manufacturer would choose this option; all manufacturers would 

essentially be forced into excusing EPA’s violation of the CAA and complying with the primary 

path. 

The lead time limits that the CAA imposes on EPA were never intended to be circumvented by 

regulatory ultimatums of this nature. The CAA envisions that EPA will promulgate standards 

taking into consideration all of the relevant factors and limits set forth in §202(a). Congress did 

not intend to set up a process under which EPA could offer illusory options with the intent of 

extracting lead time concessions from manufacturers. 

When a regulatory scheme is so heavily weighted or creates significant economic incentives such 

that only one of the options is reasonable, that option becomes a mandate and is no longer truly 

an option. The Supreme Court has acknowledged the possibility that “acute, albeit indirect, 

economic effects” of a state law could effectively restrict choices to the point that the law, while 

not directly preempted, could result in a de facto mandate that was preempted.4 Similarly, the 

U.S. District Court for the Southern District of New York held that the court had to examine the 

effect of the New York City law to first determine whether incentives for the purchase of hybrid 

taxis created a de facto mandate to purchase hybrids in order to decide whether the rules were 

preempted by the federal fuel economy requirements in the Energy Policy and Conservation Act 

(EPCA).5 Also in the vehicle context, the U.S. District Court for the Eastern District of 

California concluded that while other options existed for compliance with California’s 2002 ZEV 

amendments, they were not viable alternatives to producing advanced gasoline hybrids, the cost 

of which made likely irreparable injury supporting the auto manufacturer’s request for a 

preliminary injunction against the ZEV requirement.6 These cases make it clear that the courts 

look with disfavor upon regulatory “alternatives” that are designed to drive the regulated 

community in a particular direction. Here, the accelerated phase-in under the alternative 

compliance path would be so stringent that it would effectively eliminate it as an option, 

resulting in a de facto requirement to comply with the primary path, which is prohibited by the 

CAA. 

In this case, there is a very clear statutory directive at issue. CAA §202(a)(3)(C) unambiguously 

requires four years of lead time for heavy-duty vehicles. This prohibits EPA from finalizing the 

primary compliance path as proposed. Providing an alternative compliance path that meets the 

statutory requirements does not, and cannot, remedy the fact that the primary compliance path 

violates the statute. 

There is a relatively simple solution to this issue that meets EPA’s objectives while maintaining 

compliance with the CAA. EPA can follow the lead time requirement of the CAA and begin the 

phase-in requirement in MY 2019 for vehicles over 6,000 pounds GVWR at the currently 

proposed fleet average emissions levels. In other words, the phase-in in MY 2019 would begin at 
Tier 3 Summary and Analysis of Comments

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the level that would otherwise be in place under the currently- proposed primary path.7 Such a 

rule would comply with the CAA, fleet emissions would be at an identical level starting in MY 

2019, and there would be no meaningful environmental impact due to beginning the phase-in one 

year later. 

Recommendation: For vehicles more than 6,000 pounds GVWR, the Alliance and Global 

Automakers recommend that Tier 3 fleet average requirements for both FTP and SFTP begin in 

MY 2019 at the currently proposed MY 2019 value. This approach is in full compliance with the 

CAA, completely harmonizes with LEV III in MY 2019, and achieves virtually the same level of 

emission reduction as the “primary path” proposed by EPA. 

2 42 U.S.C § 7521(b)(3)(C).

3 42 U.S.C. §7521(a)(3)(C) (emphasis added). 

4 New York State Conference of Blue Cross & Blue Shield Plans v. Travelers Insurance Co., 514 U.S. 

645, 668 (1995).

5 Metropolitan Taxicab Board of Trade v. Bloomberg, 633 F.Supp. 2d 83, 96 (S.D.N.Y. June 22, 2009).

6 Central Valley Chrysler Plymouth v. California Air Resources Board, 2002 U.S. Dist. LEXIS 20403 at 

*15-16 (June 11, 2002). 

7 If EPA does not release the final rule by the end of 2013, then an additional year of delay for vehicles 

greater than 6,000 pounds GVWR is required, starting in MY 2020 rather than the 2019 MY. 

Chrysler Group LLC

The NMOG+NOx fleet average requirements for vehicles over 6,000 pounds GVWR should 

begin in the 2019 MY at the currently proposed 2019 MY fleet average emission level and 

compliance should end with MY 2025. 

Clean Air Act Requirements: Lead-Time for Vehicles More than 6,000 Pounds GVWR and 

Useful Life Requirements – In several places in the proposed rule, EPA seeks to circumvent 

plain limits on its authority in the CAA by offering automakers two compliance alternatives –

one that does not follow the CAA requirements but offers a reasonable compliance option, and 

one that applies the required statutory protections but imposes compliance conditions that are so 

stringent that no reasonable company would ever choose it. The CAA does not authorize this 

“poison pill” approach, under which companies are essentially forced to waive their statutory 

protections under the CAA to avoid an unreasonably burdensome compliance alternative. This is 

particularly so where the burdens imposed with the option to retain the statutory protection bear 

no rational relation to the statutory protection in question. In short, EPA’s dual-path approach, as 

described below, effectively and impermissibly eviscerates the statutory protections for industry 

that Congress intended to provide. Chrysler believes that EPA does not have the authority to 

create overt workarounds to clear statutory requirements and limitations. 

It is instructive that EPA previously failed in an attempt to circumvent the requirements of the 

CAA by proposing to adopt a similar favorable versus non-favorable dual-path approach. In 

Virginia v. EPA, (24) the D.C. Circuit firmly rejected a regulatory scheme strikingly akin to the 

proposals here: in the Virginia case, EPA promulgated a rule in 1995 that was intended to reduce 

ozone pollution in the northeastern United States by requiring states in that region essentially to 

adopt California’s vehicle emission program. However, Section 202(b)(3)(C) of the CAA 

prohibited EPA from adopting more stringent emission standards for new motor vehicles until 
Chapter 4: Proposed Vehicle Emissions Program

4-56

2004, providing that “the numerical emission standards . . . shall not be modified by the 

Administrator . . . for any model year before the model year 2004” (25). In order to overcome 

this explicit statutory limitation, EPA offered states in the region a choice: (1) adopt a vehicle 

emission program that would achieve emission reductions from new motor vehicles in the 

amount that would be achieved by California’s Low Emission Vehicle program; or (2) develop 

an acceptable “Substitute Program” that would reduce ozone precursors anywhere from 3.5 to 

6.5 times more than would the California program (26). However, as even EPA acknowledged, 

the Substitute Program was so burdensome that it was not a realistic alternative; in the words of 

the D.C. Circuit, “EPA’s alternative [was] no alternative at all, and, “only a very foolish state 

would see EPA’s offer to accept [the alternative compliance option] as a real alternative”).”

The D.C. Circuit held that EPA’s regulatory scheme, which effectively forced states to adopt 

California’s vehicle emission program in contravention of the CAA, was unlawful. In vacating 

the rule, the D.C. Circuit flatly rejected EPA’s position that because the states had an alternative 

to adopting the California motor vehicle standards, EPA itself was not imposing more stringent 

emission standards for new motor vehicles. In so holding, the Court stated: Here Congress’s 

policy and preference is loud and clear. It “is the intent of Congress that” EPA not modify the 

“numerical emission standards” for “any model year before . . . 2004.” 42 U.S.C. § 

7521(b)(1)(C). EPA therefore may not require, mandate, order, or impose conditions demanding 

that any state enact particular motor vehicle emission standards, even if those standards are 

identical to California’s. The time will come when EPA can make its case for tougher emission 

limitations on motor vehicles. But that time is years from now and, under section 202, the case 

must be made to Congress. 

Likewise, here, EPA has proposed alternative compliance paths in the proposed rule that are “no 

alternative[s] at all,” effectively forcing manufacturers to waive their statutory protections. As 

the D.C. Circuit held in Virginia v. EPA, such a regulatory scheme is prohibited by the CAA. 

Two specific examples of this impermissible regulatory structure are addressed below: (1) the 

proposed phase-in requirements for heavy-duty vehicles for compliance with the Tier 3 standards 

for NMOG+NOx; and (2) the useful life durability requirements for vehicles less than 6,000 

pounds gross vehicle weight rating (GVWR). 

24 - 108 F.3d 1397 (D.C. Cir. 1997), modified on other grounds, 116 F.3d 499 (D.C. Cir. 1997).

25 - 42 U.S.C. § 7521(b)(3)(C).

26 - 108 F.3d at 1403.

NMOG+NOx Phase-In Requirements for Heavy-Duty Vehicles: The CAA requires EPA to 

provide manufacturers of heavy-duty vehicles, defined as vehicles in excess of 6,000 pounds 

GVWR, (29) with four years of lead time (and a three-year period of “stability” with no changes 

to the standards), to comply with new automobile emission standards. Specifically, Section 

202(a)(3)(C) of the CAA, 42 U.S.C. § 7521(a)(3)(C), states: “Any standard promulgated or 

revised under this paragraph and applicable to classes or categories of heavy-duty vehicles or 

engines shall apply for a period of no less than 3 model years beginning no earlier than the model 

year commencing 4 years after such revised standard is promulgated.” (emphasis added). This 

statutory requirement is intended to ensure that manufacturers of heavy-duty vehicles are 
Tier 3 Summary and Analysis of Comments

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afforded sufficient lead time and stability to recoup their investments in new technology required 

to comply with more stringent standards (30). 

In the proposed rule, EPA attempts to thwart this statutory requirement by proposing two phasein alternatives for complying with the significantly more stringent Tier 3 NMOG+NOx tailpipe 

emissions standards. Under the more favorable primary compliance option, manufacturers must 

meet a fleet average standard that is phased-in between Model Years 2018 and 2025 for vehicles 

over 6,000 pounds GVWR, but which contravenes the CAA’s explicit four-year lead time 

requirement. Under the less favorable alternative compliance option, manufacturers must phase 

in 40 percent of their vehicles to the more stringent Tier 3 NMOG+NOx standards beginning in 

Model Year 2019, which comports with the statutory four-year lead time requirement, but adds 

the significant burden that all of the manufacturer’s vehicles must meet the final standards by 

Model Year 2021 — a full four model years ahead of the primary phase-in option (31). 

Assuming EPA issues a Tier 3 final rule in late 2013, as planned, Model Year 2014 already 

would have begun. Therefore, the CAA requires that the Tier 3 standards applicable to heavyduty vehicles take effect no earlier than Model Year 2019 (i.e. four model years after the revised 

standards are promulgated per Section 202(a)(3)(C), that is, commencing with the 2015 Model 

Year). EPA’s proposed primary compliance option, however, would require manufacturers of 

heavy-duty vehicles to begin complying with the stringent Tier 3 standards in 2018 (i.e., only 

three model years after the revised standards are promulgated), and therefore would contravene 

the lead time requirement in Section 202(a)(3)(C) of the CAA. Conversely, although EPA’s 

alternative compliance option does meet the statutory four-year lead time requirement, it 

unreasonably imposes unduly and significantly more burdensome compliance requirements than 

the primary compliance option, and does not present manufacturers with a realistic choice. 

Moreover, these undue burdens are not rationally related to the four-year lead time requirement 

and thus are clearly designed as a punitive stick to force manufacturers to “choose” the non-CAA 

compliant primary option with only three years of lead time. 

As described in greater detail in the comments provided by the Alliance of Automobile 

Manufacturers and Association of Global Automakers, (32) the alternative compliance option, 

which complies with the four-year lead time requirement but requires manufacturers to certify all 

of their vehicles to the Tier 3 standards a full four model years sooner than the primary phase-in 

option, is so burdensome that no reasonable manufacturer would ever choose it; all 

manufacturers would essentially be forced into selecting the primary phase-in option and turning 

a blind eye to EPA’s blatant violation of the CAA’s lead time requirements for heavy-duty 

vehicles. When a regulatory scheme is so heavily weighted or creates significant economic 

incentives such that only one of the options is reasonable, that option becomes a mandate and is 

no longer truly an option. Providing a significantly more burdensome alternative compliance 

path that meets the statutory requirements does not, and cannot, remedy the fact that the primary 

compliance path violates the statute. 

This dual-path approach that EPA proposes would violate the CAA for an additional reason, as 

well. Under Section 202(a)(3)(A)(i) of the CAA, EPA is required to promulgate standards 

“which reflect the greatest degree of emission reduction achievable through the application of 

technology which the Administrator determines will be available for the model year to which 
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such standards apply, giving appropriate consideration to cost, energy, and safety factors 

associated with the application of such technology” (33). Thus, the CAA implicitly requires EPA 

to select the single standard that reflects the greatest degree of emission reduction achievable. 

Here, it simply cannot be the case that both the primary compliance option (which begins in 

Model Year 2018 and requires full compliance with the more stringent standards by 2025) and 

the alternative compliance option (which begins in Model Year 2019 and requires full 

compliance with the more stringent standards by 2021) reflect the greatest degree of emission 

reduction achievable taking into account cost, energy, and safety. Rather, if the three-year phasein under the alternative compliance option is in fact achievable considering the specified factors, 

then the primary compliance path, which affords manufacturers seven years to meet the more 

stringent standards, cannot be reconciled with the CAA requirement that EPA promulgate 

standards reflecting the greatest degree of emission reduction achievable. The more likely 

explanation, however, is that the primary compliance option reflects the greatest degree of 

emission reduction that EPA believes is truly appropriate, whereas the alternative compliance 

option is intentionally so burdensome—and therefore far beyond reflecting the greatest degree of 

emissions reduction achievable—that manufacturers will be forced to waive their statutory 

protections and choose the primary path. This attempt to circumvent the statutory protections 

embodied in the CAA cannot be reconciled with the plain provisions of the Act. 

Further, Chrysler objects to the requirement that if a manufacturer chooses the alternative 

compliance path for any of its vehicles, all of its vehicles, including light-duty vehicles and those 

heavy-duty vehicles for which the manufacturer is willing to comply with three years lead time, 

must nevertheless meet the final Tier 3 NMOG+NOx standards by 2021 (instead of 2025 under 

the primary compliance option). This regulatory scheme, which sweeps in a manufacturer’s 

entire fleet if the manufacturer chooses to pursue the alternative compliance option for even just 

a single vehicle model, cannot be characterized as an incentive to forego the four-year lead time 

requirement; rather, it is a penalty imposed on manufacturers that refuse to forego their statutory 

protections. There is no rational basis for penalizing a manufacturer’s entire vehicle fleet simply 

because the manufacturer chooses to exercise its statutory right to four years of lead time for one 

heavy-duty vehicle model. Plainly, any emissions benefits of earlier compliance would accrue 

for those models of vehicles for which the manufacturer might choose earlier compliance. But 

precluding that choice and imposing more stringent standards even for those models that might 

comply early, just because a different model or models cannot comply early, has no 

environmental rationale except to penalize the choice of later compliance for the other models. 

That design is arbitrary, unreasonable, and unlawful (34). 

Recommendation: Chrysler recommends that, for vehicles over 6,000 pounds GVWR, the Tier 3 

fleet average requirements for FTP and SFTP NMOG+NOx begin in MY 2019 at the currently 

proposed Model Year 2019 fleet average emissions levels (under the primary compliance option) 

and require full compliance only at Model Year 2025. This approach is in full compliance with 

the CAA, completely harmonizes with LEV III in MY 2019, and will achieve the same level of 

emission reduction as the proposed rule. 

29 - See 42 U.S.C. § 7521(a)(3)(C). A “heavy-duty vehicle” is a “truck, bus, or other vehicle 

manufactured primarily for use on the public streets, roads, and highways . . . which has a gross vehicle 

weight . . . in excess of six thousand pounds.” 42 U.S.C. § 7521(3)(C).
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30 - See, e.g., Natural Res. Def. Council v. Thomas, 805 F.2d 410, 433 (D.C. Cir. 1986) (noting that the 

four-year lead time requirement “was enacted for the benefit of the manufacturers, to allow time for them 

to design and develop engines in compliance with newly promulgated standards”) (citing H.Rep. No. 294, 

95th Cong., 1st Sess. 274–75 (1977) (discussing “abundant lead time”), reprinted in 4 Leg. Hist. 2741–42, 

J.A. at 19–20).

31 - EPA proposes to adopt a similar dual-path approach for “heavy-duty vehicles” as defined by EPA at 

40 CFR §86.1803-01 (i.e., vehicles greater than 8,500 pounds GVWR but less than or equal to 14,000 

pounds GVWR). See 78 Fed. Reg. at 29,875-29,877. Under the proposed primary compliance option, 

manufacturers must meet a declining fleet average standard for NMOG+NOx beginning in Model Year 

2018, in contravention of the CAA’s explicit four-year lead time requirement. Alternatively, 

manufacturers can choose to comply beginning in Model Year 2019, which comports with the four-year 

lead time requirement, but then are subject to a percent-of-vehicles phase-in approach rather than a 

declining fleet average. Again, EPA’s “poison pill” approach cannot be reconciled with the CAA. 

Accordingly, Chrysler recommends that EPA start the declining fleet average in Model Year 2019, 

consistent with the CAA’s four-year lead time requirement.

32 - Alliance/Global Comments, at 4.

33 - 42 U.S.C. § 7521(a)(3)(A)(i),

Our Response:

The Alliance of Automobile Manufacturers (Alliance), and Association of Global 

Automakers (Global) and Chrysler LLC commented on the alternative phase-in proposed for 

vehicles over 6000 lbs GVWR. These comments questioned whether the proposed structure of 

and restrictions on the use of the alternative phase-ins were so onerous as to unduly restrict a 

manufacturer from choosing the alternative phase-ins and their lead time and stability provisions 

as set forth in the Clean Air Act. The commenters criticized the proposed requirement that a 

manufacturer using the alternative phase-ins apply the alternative schedules to its entire lightduty fleet, both below and above 6,000 lbs GVWR. EPA had proposed this provision to 

minimize the complexity of complying with the alternative phase-in if a manufacturer’s heavier 

and lighter light-duty vehicles had different compliance structures. 

In considering these comments, EPA also considered that during the development of the 

Tier 3 program and in their comments, the same auto industry commenters consistently urged 

EPA to design the Tier 3 program to harmonize with the California LEV III standards as closely 

and as early as possible. As discussed in detail in Section IV.A of the preamble, extensive data 

that EPA has generated or received continue to support the conclusion that the primary fleetaverage standards provide a compliance path that is feasible across the industry and that closely 

harmonizes with LEV III. EPA believes that we have reasonably resolved these somewhat 

competing concerns – early harmonization vs. additional lead time – by finalizing the primary 

declining fleet average standards as proposed while also finalizing revised alternative phase-in 

compliance schedules (see preamble Section IV.A.2.c). In response to the comments, we have 

revised the alternative phase-in schedules to reduce their associated burden for manufacturers, 

while still maintaining environmental benefits that are equivalent to the primary program. We 

also include provisions in the percent-of-sales phase-in alternatives that allow manufacturers to 

exclude vehicle models that begin their 2019 model year production early in 2018, in order to 

provide four years of lead time.
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Specifically, we have removed from the alternative phase-in provisions the requirement 

that a manufacturer apply the alternative schedules to its entire light-duty fleet including vehicles 

below 6,000 lbs GVWR. For the practical functioning of the program, the final rule requires that 

any manufacturer choosing to use the alternative phase-in apply all four alternative phase-in 

schedules to its entire light-duty fleet above 6,000 lbs GVWR. We believe that the alternative 

phase-ins allow manufacturers to comply with emission standards in a time frame that is clearly 

feasible and fully compliant with the CAA requirements for lead time and regulatory stability. 

To the extent that manufacturers choose to use them, the alternative would result in overall 

emission reductions essentially identical to those of the primary program. 

As explained in the preamble, the alternative phase-in schedules would begin to apply to 

each vehicle for either MY 2019 or MY 2020, depending on exactly when the manufacturer 

begins production of the vehicle. (See Section 86.1811-17(b)(8)(i) for how we implement this 

provision.) For models that begin MY 2019 production after the fourth anniversary of the 

signing of the final rule, the alternative phase-in would provide four full years of lead time and 

would first apply for MY 2019. The phase-in obligation would be calculated based only on 

those vehicles beginning production after the fourth anniversary date. For models beginning 

production before that date, the alternative phase-in would first apply for MY 2020, and the 

phase-in percentage for MY 2020 would be based on the manufacturer’s entire fleet of heavier 

light-duty vehicles. Based on historical certification patterns, few models begin production 

before mid-calendar-year, so we expect that the vast majority of MY 2019 vehicles will begin 

production after the 4-year anniversary and thus the alternative phase-ins, if chosen, will 

typically apply beginning in MY 2019. 

At the time of certification for MY 2018, a manufacturer must declare whether it intends 

to apply the alternative phase-in schedules to its heavier light-duty vehicles. A manufacturer 

choosing the alternative phase-ins would be committed to this phase-in approach for the duration 

of the phase-ins, and could not later choose the fleet-average approach for NMOG+NOX

standards. For all vehicles below 6,000 lbs GVWR, the primary program will apply, beginning 

in MY 2017. For a manufacture’s vehicles subject to the alternative phase-ins, there would be no 

new tailpipe emissions requirements beyond the Tier 2 program until the beginning of the 

alternative phase-in schedules; that is, MY 2019 or 2020, as explained above.

As discussed above, a manufacturer choosing the alternative phase-in approach for its 

heavier light-duty vehicles would be required to use all four phase-ins together. The next 

paragraphs explain how each of the alternative phase-ins requires an increasing percent of the 

manufacturer’s sales to comply with the alternative standards. Thus, until the end of the phaseins, some percent of a manufacturer’s affected vehicles will meet the new standard and the 

remainder of that year’s sales will not yet comply with Tier 3. For the practical functioning of 

the program, a manufacturer choosing the alternative phase-ins would be required to comply 

with exactly the same segment of their fleet in each model year for all four alternative phase-ins. 

For example, a manufacturer that complies with the 70 percent MY 2020 requirement for the 

FTP NMOG+NOX standard with a segment of its vehicle fleet must meet the 70 percent MY 

2020 requirement for the FTP PM standard with the same set of vehicles.

 
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For the FTP and SFTP NMOG+NOX alternative phase-in schedules, once the phase-in is 

complete for a segment of a manufacturer’s fleet, the standards continue for that set of vehicles 

through MY 2024, after which the full Tier 3 program applies regardless of the phase-in strategy. 

Thus, the fleet-average standards that decline through MY 2024 do not apply for these vehicles.

 

Although manufacturers would implement all four alternative phase-in schedules 

together, as discussed above, each alternative phase-in has unique characteristics. The following 

paragraphs explain the unique provisions of each. 

Alternative Phase-In Schedule for the FTP NMOG+NOX Standard

Instead of the primary FTP NMOG+ NOX declining fleet average standards, a 

manufacturer choosing the alternative phase-ins would comply with a stable fleet average FTP 

NMOG+NOX standard of 30 mg/mi that would apply to an increasing percentage of a 

manufacturer’s combined sales of LDVs and LDTs above 6,000 lbs GVWR and MDPVs. This 

percent phase-in would match the percentages in the primary PM percent phase-in schedule, as 

discussed above – specifically, 40 percent of MY 2019 heavier light-duty vehicles (excluding 

those vehicles with production beginning before the 4-year anniversary), 70 percent of all of its 

heavier light-duty vehicles in MY 2020, and 100 percent compliance in MY 2021 and later 

model years. 

Alternative Phase-In Schedule for the FTP PM Standard

Instead of the primary FTP PM percent phase-in schedule, a manufacturer choosing the 

alternative phase-ins would postpone the beginning of its FTP PM phase-in for its LDVs and 

LDTs above 6,000 lbs GVWR and MDPVs until MY 2019 or 2020 (depending on the dates 

production begins for its vehicle models, as discussed above). The manufacturer would then 

comply with the 3 mg/mi per-vehicle FTP PM standard (and the 6 mg/mi in-use standard) on an 

increasing percentage of these vehicles, following the 40-70-100 percentage phase-in of the 

primary PM program -- specifically, 40 percent of MY 2019 heavier light-duty vehicles 

(excluding those vehicles with production beginning before the 4-year anniversary), 70 percent 

of all of its heavier light-duty vehicles in MY 2020, and 100 percent compliance in MY 2021 and 

later model years. 

Alternative Phase-In Schedule for the SFTP NMOG+NOX Standard

As with the other alternative phase-ins, instead of the primary SFTP NMOG+ NOX

declining fleet average standards, a manufacturer choosing the alternative phase-ins would 

comply with a stable fleet average SFTP NMOG+NOX standard of 50 mg/mi that would apply to 

an increasing percentage of a manufacturer’s combined sales of LDVs and LDTs above 6000 lbs 

GVWR and MDPVs. This percent phase-in again would match the percentages in the primary 

PM percent phase-in schedule, as discussed above – specifically, 40 percent of MY 2019 heavier 

light-duty vehicles (excluding those vehicles with production beginning before the 4-year 

anniversary), 70 percent of all of its heavier light-duty vehicles in MY 2020, and 100 percent 

compliance in MY 2021 and later model years.

Alternative Phase-In Schedule for the US06 PM Standard
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Finally, instead of the primary US06 PM percent phase-in schedule, a manufacturer 

choosing the alternative phase-ins would postpone the beginning of the US06 phase-in for its 

LDVs and LDTs above 6,000 lbs GVWR and MDPVs until MY 2019 or 2020 (depending on the 

dates production begins for its vehicle models, as discussed above). The manufacturer would 

then comply with the 10 mg/mi US06 PM standard for 40 percent of MY 2019 heavier light-duty 

vehicles (excluding those vehicles with production beginning before the 4-year anniversary), 70 

percent of all of its heavier light-duty vehicles in MY 2020, with 100 percent compliance in MY 

2021, and then 100 percent compliance with the 6 mg/mi standard in MY 2022 and later model 

years.

With regard to Chrysler’s comments in paragraph “31” above concerning HD vehicles, reference 

Chapter 4.2.1 of this Summary and Analysis of Comments document.

4.1.4. Feasibility

What Commenters Said:

Emissions Control Technology Association (ECTA):

We agree with EPA’s conclusion that the emissions reduction requirements in the proposed rule 

are technically achievable, and the pathways illustrated represent cost-effective solutions to meet 

these reductions. 

The technology choices are numerous. Many technologies are on some vehicles already, and can 

readily be applied to others. Examples include hydrocarbon adsorbers (Ford SAE 2013-01-1297, 

Nissan SAE2008-01-0449, SAE2009-01-1076), high cell density substrates (only a few 900-csi 

applications), secondary air (Umicore SAE 2012-01-1245), and advanced thermal management 

strategies. 

International Council on Clean Transportation (ICCT)

The feasibility of the proposed Tier 3 standards has already been demonstrated by the numerous 

vehicles that already meet the California LEV III standards and Tier 2 bin 2 standards. The two 

keys to low emissions are precise air/fuel control and rapid catalyst light-off. Since the Tier 2 

standards were adopted there have been major improvements in both of these areas, making 

compliance with the proposed Tier 3 requirements easier. 

Manufacturers of Emission Controls Association (MECA)

MECA agrees with EPA staff’s assessment that achieving the proposed Tier 3 

exhaust...emission standards and associated emission reductions are both technically feasible 

and cost-effective. 

This fact is clearly demonstrated by the more than two million SULEV- and PZEV-compliant 

light-duty vehicles that have been sold in the U.S. market since these near-zero emission, 
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gasoline vehicles were first introduced more than ten years ago. This technology base of 

advanced three-way catalysts, exhaust hydrocarbon adsorber materials, high cell density 

substrates, emission system thermal management strategies, secondary air injection systems, 

advanced carbon canisters, advanced low fuel permeation materials, and air intake hydrocarbon 

adsorber materials that have already been commercialized for a variety of PZEV gasoline vehicle 

applications can be extended and further optimized to allow all light-duty ...gasoline vehicles to 

achieve the exhaust ...emission reductions needed to comply with the Tier 3 vehicle emission 

proposals put forward by EPA. On the exhaust side, Tier 3/LEV III emission technologies 

(including advanced three-way catalysts, advanced high cell density substrates, and hydrocarbon 

adsorber catalysts) are highlighted in a new MECA report entitled: “LEV III and Tier 3 Exhaust 

Emission Control Technologies for Light-Duty Gasoline Vehicles” (available on MECA’s 

website, www.meca.org, under Resources >> Reports). A recent SAE paper (SAE paper no. 

2011-01-0301) demonstrates how advanced three-way catalysts utilizing high cell density 

substrates can be combined to achieve Tier 3, Bin 20 or Bin 30, exhaust emission levels on a 

four-cylinder, light-duty gasoline vehicle. A 2013 SAE paper (SAE paper no. 2013-01-1297) 

provides insights into recent improvements in performance and durability of hydrocarbon 

adsorber catalysts. These latest generation hydrocarbon adsorber catalysts show improved coldstart hydrocarbon emission reductions with reduced precious metal content compared to earlier 

generations of hydrocarbon adsorber catalysts. Hydrocarbon adsorber catalysts are available to 

assist in difficult Tier 3 applications, such as larger weight trucks and SUVs.

In addition, advanced diesel emission control technologies, including diesel particulate filters 

(DPFs), lean NOx adsorber catalysts, and selective catalytic reduction (SCR) catalysts, will be 

combined with future, advanced diesel engines to allow light-duty diesel vehicles to achieve the 

proposed Tier 3 emission limits, including EPA’s proposed Tier 3, Bin 30 exhaust standards. 

MECA agrees with EPA’s projections that future hydrocarbon adsorber catalyst applications will 

be targeted at larger light-duty vehicles. MECA believes that any Tier 3 applications of 

hydrocarbon adsorber catalysts will rely on “passive” hydrocarbon adsorber approaches that 

combine a hydrocarbon adsorber function with a three-way catalyst function on the same 

substrate (typically in a layered coating architecture in an underfloor converter location), rather 

than “active” hydrocarbon adsorber designs that utilize some type of an exhaust valve to direct 

the exhaust through a hydrocarbon adsorber material during cold-start. Passive hydrocarbon 

adsorber catalysts can provide effective cold-start hydrocarbon emission reductions at a 

significant cost advantage versus active hydrocarbon adsorber system designs. MECA also 

believes that manufacturers will have the opportunity to optimize emission system designs with 

advanced powertrains as they move forward with their future light-duty vehicle greenhouse gas 

compliance strategies. Strategies such as engine downsizing, vehicle weight reductions, and 

improved engine combustion technologies will help to off-set emission system cost increases for 

future Tier 3 compliance. 

In summary, there are significant opportunities to reduce both criteria pollutant and greenhouse 

gas emissions from the transportation sector through the design of fuel-efficient powertrains that 

include advanced exhaust emission controls for meeting even the most stringent criteria pollutant 

standards that are included in EPA’s proposed Tier 3 program. MECA believes that advanced 
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emission control systems have a critically important role in future policies that aim to reduce 

mobile source criteria pollutant and greenhouse gas emissions. 

MECA believes that advanced emission control systems have a critically important role in future 

policies that aim to reduce mobile source criteria pollutant and greenhouse gas emissions, and we 

strongly supports EPA’s Tier 3 emission proposal.

Pennsylvania Department of Environmental Protection (DEP)

DEP supports EPA’s proposed Tier 3 emission standards for vehicles. The proposed standards 

would be met by vehicle manufacturers beginning in model year 2017 and phasing in through 

later model years. Vehicles sold in states such as Pennsylvania that have adopted light-duty 

vehicle emission standards promulgated by California Air Resources Board (CARB) will be 

meeting the same standards for model year 2015 and later vehicles. States that adopted CARB 

light-duty vehicle standards comprise nearly 50 percent of the national market for these vehicles. 

Technological developments in the automotive field that have already occurred or that are in the 

developmental pipeline as a result of CARB and EPA efforts will allow automobile 

manufacturers to effectively meet these more stringent standards for NOx, VOC, and PM2.5 by 

the year 2021. 

Sierra Club

The Draft RIA provides sufficient evidence that the proposed Tier 3 standards are 

technologically feasible for a range of existing vehicles. Already, manufacturers are 

implementing technologies that reduce NMOG + NOx emissions under more challenging 

circumstances such as during cold starts, and it is anticipated that manufacturers can make 

necessary technology improvements to comply with the Tier 3 standard. 

EPA also demonstrates feasibility of meeting the proposed rule’s PM exhaust emissions 

reductions; some fleets already are achieving Tier 3 level reductions, and there are a number of 

available controls and practices, such as reduced oil consumption, which will allow future fleets 

to meet the proposed standards. 

State of Utah

The bulk of pollutants from most of today’s vehicles are emitted during cold starts—ignition and 

the first few miles of driving before conventional catalytic converters warm up enough to be 

effective—and during fueling. The Tier 3 standards would address these issues by requiring that 

by 2017 new vehicles have larger catalytic converters to better remove NOx, hydrocarbons, and 

carbon monoxide; heat pumps that warm the catalytic converter almost immediately upon 

ignition to avoid an initial rush of emissions after a cold start.... These low-emission vehicle 

technologies are in use today in California and other countries and have a proven record of 

results. 

Our Response:
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All commenters that commented on the technological feasibility of the proposed Tier 3 

standards pointed to the current or near-term availability of technological pathways to 

compliance with all or most of these standards. For the FTP and SFTP NMOG+NOx standards 

and the FTP PM standard, no commenters expressed significant concern about the feasibility of 

the proposed levels (although some argued for even more stringent standards, as addressed in 

Chapter 4.1.2 above). In the proposal, we concluded that all of the Tier 3 emissions standards 

are technologically feasible in the time frame of the program. The technical conclusions we 

reached at that time have been further reinforced by information we received in the public 

comments or has otherwise become available and placed in the docket for this rulemaking. After 

considering the comments received and with additional supporting information in Chapter 1 of 

the RIA, we continue to conclude that the Tier 3 standards are feasible and reasonable, 

considering lead-time provided and expected compliance costs. 

See Section IV.A.5 of the preamble and Chapter 1 of the RIA for more detailed 

discussions of the feasibility of the Tier 3 light-duty vehicle standards.

4.1.4.3. Impact of Gasoline Sulfur on Feasibility of the Vehicle Tailpipe Standards

EPA Tier 2 In-Use Sulfur Test Program

What Commenters Said:

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

The EPA in-use fleet test examined sulfur effects at two levels (5 and 28 ppm) and had a number 

of questionable test practices including using an unrealistic base fuel (0% ethanol, high 

aromatics, very low olefins at essentially 0 vol%, and high T50); requiring mild operation before 

testing; test cycle; vehicle history and data analysis. 

A more recent EPA study was conducted beginning in 2009 to understand gasoline sulfur effects 

on the in-use Tier 2 fleet (7). For this EPA effort (hereinafter termed the “In-use sulfur study”), 

in-use MY 2007-2009 vehicles from the state of Michigan were evaluated for sulfur reversibility, 

instantaneous, and mileage accumulated effects at 28 ppm and 5 ppm sulfur. The fuel used for 

these experiments contained 0 vol% ethanol and was doped with dibutyl disulfide to increase 

sulfur content from 5 to 28 ppm. This test fuel is not representative of in-use fuels due to its low 

ethanol content, high aromatics, very low olefins at essentially 0 vol%, and high T50. While this 

study was not designed to evaluate fuel effects other than sulfur, the temperature of the exhaust, 

emissions species present, and potential catalyst effects are not representative of real world 

driving conditions. The sulfur history of the vehicles /catalysts is also unclear. 

Vehicle operation prior to the testing process is also an area of concern. The civilian or NVFEL 

drivers were instructed to “avoid hard accelerations and high speeds in an effort to preserve the 

“as-received” state of the catalyst”. This instruction contradicts the overall objectives of this 

program and biased the “as-received” state of the catalyst. 
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The report of the EPA In-Use sulfur study contains a significant amount of statistical analysis, 

however interestingly, raw data trends are largely absent from the body of the document. In 

review of the raw data provided in the appendix, it is clear that there are issues concerning the 

drive cycle chosen to evaluate sulfur effects. The pre-and post-catalyst clean out emissions on 28 

ppm sulfur fuel show varying trends where, in some cases, the emissions levels post catalyst 

clean out were higher than the pre-catalyst clean out. The drive cycles chosen for both the 

catalyst clean-out and mileage accumulation are also only one set of potential driving conditions 

and typically would not be seen in-use. Previous studies have shown that sulfur 

accumulation/reversibility is sensitive to driving cycle. 

EPA constructed models of emissions versus mileage for each vehicle, as shown in Figure 7-7 of 

the In-Use Study report. Some models seem to track the data very well, while others do a poor 

job. However, EPA did not provide any descriptive statistics for the model, but a number of the 

vehicles (e.g., 0046 and 0178) seem to have particularly poor fit. EPA recognizes this (page 45) 

and attributes it to the “variability in the emissions testing.” However, this also calls into 

question the parameters that EPA has assumed to be important with respect to fuel sulfur impacts 

on emissions. 

A primary issue with EPA’s statistical analysis of the data from the In-Use sulfur study is that 

the individual vehicles were treated as random variables. If this is true, a subset of the total 

vehicle population would be expected to have the same responses as the entire population. 

However, EPA did not present an analysis of whether the different fleets had an impact on the 

analysis. This should have been done to determine whether EPA’s assumption that “vehicle” is a 

random variable is valid. This is of key importance because EPA used different sets of vehicles 

to analyze different emission effects. For instance, the clean-out effect at 28 ppm sulfur was 

measured on a fleet of 81 vehicles, and the clean out effect at 5 ppm sulfur was measured with a 

fleet of 23 vehicles, which were a subset of the larger fleet. 

If the vehicles were truly random variables as EPA assumed, then the responses of the individual 

models would not be expected to be different, and each vehicle would be treated the same as any 

other vehicle. However, EPA reported most of the results according to vehicle model, suggesting 

that EPA itself doesn’t believe in the random variable assumption. See, for example, Figures 7-2 

and 7-5 of the In-Use Study—these plots, as well as plots in Appendix E, suggest that there are 

major differences in how different vehicle models responded to the sulfur clean-out cycle with 

28 ppm sulfur fuel. The statistical analysis that EPA conducted did not account for the possibility 

that the variability of responses within models to fuel differences could be very different from 

the variability between models. This is important statistical information and can help sharpen the 

analysis. Treating cars as random variables is a good assumption when one sample of each model 

is tested; however, when multiple samples of each model are tested, this assumption may not be 

valid. In any case, this assumption should have been tested by EPA on the large 81-vehicle fleet 

that tested 5 samples of most models. 

EPA made a mid-test change to the procedure for mileage accumulation (from multiple dyno 

FTP runs to on-road mileage accumulation); however there was no evaluation of the significance 

of this change to the resulting emissions effects. In addition, the report references that between 

and within vehicle, variances were significant. An influence analysis should have been 
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completed, such as was done in the EPAct study, on all emissions to show potential biases due to 

specific vehicle types, including a sensitivity case removing those vehicles having significant 

influence to the overall conclusions in the report. This was completed only for Bag 2 NOx. Also, 

due to the vehicle variances, a number of statistical models were applied to the data which would 

not converge. The final structure chosen was done such that “due to limited available options, we 

acknowledge that there might be some limitations inherent in the assumption of constant distance 

between two measurements” (assumes regularly spaced time intervals for all vehicles which is 

not the case when emissions were measured at different mileage accumulation rates). 

Finally, a large number of emissions concentration measurements taken from Bags 2 and 3 were 

either lower or similar to the measured background concentrations. The percent differences 

which are referenced in these cases represent a very small magnitude, which may have errors 

associated with the analyzers’ capability. The report does not indicate the measurement error at 

levels below the analyzer calibration points for NOx in Bag 2 and does not mention the 

calibration points or error for other low emitting species. 

EPA presented the results from the data analysis of the In-Use Study in terms of percentages. 

While this is a typical outcome of statistical analysis using the log transformation of emission 

data, it can distort the apparent impacts of lowering gasoline sulfur content. Because mass 

emission levels in Bag 1 of the FTP are substantially larger than emissions from Bag 2 and Bag 3, 

even small percentage differences in Bag 1 may be similar in size to very large percentage 

differences in Bag 2 and Bag 3 when mass emission rates are considered. 

Marathon Petroleum Company LP (MPC)

The in-use fleet test examined sulfur effects at two levels (5 and 28 ppm) and had a number of

questionable test practices including using an unrealistic base fuel (0% ethanol, high aromatics, 

very low olefins at essentially 0 vol%, and high T50); requiring mild operation before testing; 

test cycle; vehicle history and data analysis. 

Manufacturers of Emission Controls Association (MECA)

EPA has released a thorough and well-designed sulfur effects study on 81 in-use Tier 2 lightduty gasoline vehicles that clearly showed significant reductions in criteria pollutants in 

comparing emissions performance on gasoline with 28 ppm sulfur versus 5 ppm sulfur. Work 

published in a 2011 SAE technical paper (SAE paper no. 2011-01-0300) shows similar, 

significant emission benefits on a 2009 model year PZEV vehicle operated with 3 ppm sulfur 

gasoline versus 33 ppm sulfur gasoline. In this gasoline sulfur effects study, on a 2009 PZEV 

passenger car, the results clearly show that the underfloor converter used on the close-coupled + 

underfloor PZEV catalytic converter system was susceptible to sulfur-related performance 

degradation due to its cooler operating temperatures during the FTP test cycle using a 33 ppm 

sulfur-containing gasoline. The loss in NOx performance of this underfloor PZEV converter in 

successive FTP tests could be recovered to some extent, or avoided to a large degree, by either 

purging stored sulfur off the underfloor converter with the use of a higher speed and load test 

cycle (i.e., the US06 test cycle) sandwiched between FTP tests, or using a gasoline with 

significantly lower sulfur levels (i.e., a 3 ppm sulfur-containing gasoline).
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As Mr. Grundler stated, EPA has released a thorough and well-designed sulfur effect study on 81 

in-use Tier 3 light duty gasoline vehicles that clearly show significant reductions in criteria 

pollutants in comparing emission performance on gasoline with 28 ppm sulfur versus five ppm 

sulfur.

Our Response: 

The American Petroleum Institute (API), MPC and the Manufacturers of Emissions 

Controls Association (MECA) all commented on EPA’s analysis of the effects of gasoline sulfur 

on in-use light-duty vehicle emissions. One of the comments received was with respect to the 

fuel used in our in-use sulfur analysis and the interaction various fuel properties could have on 

the overall emissions. There has been little or no published data in the literature pertaining to the 

interaction of sulfur with other fuel properties such as aromatics or ethanol content. Given this 

fact, we chose to conduct our study using Tier 2 (non-ethanol) certification fuel as a base. The 

extent to which ethanol might raise or lower exhaust (and catalyst) temperatures faster after cold 

start or reduce or increase the sulfur poisoning impacts on cold-start emissions to some extent is 

not known and API does not provide substantive data on that issue. There is also a propensity 

for ethanol to lean-out transients and open-loop operation that would also tend to increase NOx 

and lower NMOG emissions. There does not appear to be a clear theoretical basis to assume a 

bias in NMOG+NOx emissions results that would result solely from the use of a non-ethanol test 

fuel when assessing sulfur impacts on exhaust emissions, or that using test fuel with ethanol 

would have substantially changed the program’s overall conclusions. 

API also commented on the drive cycle used in our analysis of gasoline sulfur. The 

objective of the instructions to the vehicle transport driver with respect to hard acceleration and 

high speed driving was to limit the opportunity for the state of catalyst sulfur loading to change 

appreciably (up or down) from how it was when the vehicle was acquired from the owner. This 

does not indicate that we intended or continued to drive the vehicle in a manner that would result 

in a change in the state of the catalyst. The transport driving in question covered relatively short 

distances from the owner’s location to the test facility, and may have involved rural, city and/or 

highway driving. Aggressive and high speed driving was avoided because it is known to change 

the state of the catalyst. 

The drive cycles chosen to evaluate sulfur effects represent the types of driving that 

manufacturers must perform in their certification testing and will need to protect for during inuse emissions performance evaluations of their certified vehicles. No single cycle represents all 

“typical” driving. We agree that both sulfur accumulation and reversibility are sensitive to 

driving cycles; however this study was not designed to evaluate cycles but instead to establish 

the potential for sulfur to degrade emission performance that compromises a vehicle’s ability to 

meet emission standards, particularly the new stringent Tier 3 levels.

With respect to the comment on model predictions and the vehicle parameters included in 

the model, the intent of the study was to assess the aggregate behavior of a representative sample 

of the Tier 2 fleet. While we agree that many catalyst and engine operation parameters interact 

with sulfur to influence emissions and could be studied as part of an engineering analysis, 

attempting to account for all of them across the test fleet would be very complex and 
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unnecessary for our purpose of assessing the impacts across a broad cross section of vehicles. In 

terms of the accuracy of the mixed model, overall, the model predictions were in good agreement 

with the data. Although there were some instances where the model overestimated the effect of 

sulfur and some instances where the model underestimated the effect of sulfur, we believe that 

the variability in predictions does not meaningfully affect the overall conclusions, since the 

model predictions were not biased toward a single direction. Furthermore, the study was 

designed to examine the effect of sulfur on in-use emissions from the fleet, rather than from 

individual vehicles.

With respect to the treatment of vehicles as random variables, the mixed model accounts 

for correlation in the data through the inclusion of random effects and modeling of the 

covariance structure. The random effects represent parameters that are allowed to vary over 

vehicles reflecting the natural heterogeneity in the vehicle fleet. In the draft report, the analyses 

modeled each vehicle family as the random effect for the mixed model examining the effect of 

clean-out, since multiple vehicles were tested for each make and model. For the mixed models 

examining the effect of clean-out at 5 ppm and the effect of sulfur level, the analysis modeled the 

individual vehicle as the random effects. However, since the draft report, additional vehicles 

were tested and included in the analyses. Therefore, in the final report, the assumptions for the 

mixed model have been modified to model vehicle family as the random effect for all three 

datasets. By assuming each individual vehicle family as a random effect, we assumed the 

presence of substantial between-vehicle family variability, based on the results from the 

likelihood ratio test assessing the significance of the variation between vehicle families. In 

addition, consistent with the change in the assumption of random effect, the data plots in the final 

report are presented in terms of vehicle models. The method of treating vehicles as random 

effects in order to properly model the covariance structure has been utilized in a similar study 

examining the effects of fuel properties, including sulfur, on emissions.3 Furthermore, the 

external peer-reviewers provided support by stating that “the statistical modeling approach seems 

appropriate” considering the study design, and the structure and limitations of the emissions 

dataset, since the approach accommodates missing data, irregularly spaced measurements, and 

within-vehicle effects.4 In the final report, we also performed additional sensitivity analyses to 

examine the extent to which the results of the analysis are affected by the vehicles in the dataset.

With respect to the comment regarding the variability of responses within and between 

models, as discussed in other responses to comments, in order to account for both the within- and 

between-vehicle model variability, in addition to modeling a covariance structure, each vehicle 

family was treated as a random effect in the final analyses for all three datasets which included 

the test results of multiple samples from each vehicle model.

Regarding API’s comment that “EPA made a mid-test change to the procedure for 

mileage accumulation,” the additional on-road mileage accumulation was necessary to fully re-

 

3 Chapter 6 of the Regulatory Impact Analysis for the Control of Hazardous Air Pollutants from Mobile Sources 

Final Rule, EPA 420-R-07-002, February 2007, last accessed on the Internet on 12/04/2013 at the following URL: 

http://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P1004LNN.PDF.

4

Four Peer Reviews in Support of the Tier 3 Rulemaking: Fuel Sulfur Effects Analysis draft report . U.S. 

Environmental Protection Agency, Washington, D.C. Documents available at 

http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=240145.
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load the catalyst to a level that represents relatively mild in-use driving. The test results with 

mileage accumulation constituted a part of the “sulfur level effect” dataset assessing the impact 

of high and low sulfur fuel on emissions starting with an “unloaded” catalyst. We evaluated the 

impact of mileage accumulation by including the ‘mileage’ term as well as the ‘sulfur level’ and 

‘mileage’ interaction terms in our statistical modeling. The mixed model results showed that the 

interaction term was not statistically significant, suggesting that the rate of sulfur loading does 

not vary by accumulated mileages after the clean-out between high and low fuel sulfur levels. 

The peer-reviewers supported our statistical modeling by stating that “overall, the methodology 

for determining the in-use sulfur effect for models with and without the sulfur and mileage 

interaction term appears to be sound.”5

To evaluate the robustness of the statistical analyses assessing the overall in-use 

emissions reduction between operation on high and low sulfur fuel, a series of sensitivity 

analyses were performed to assess the impacts on study results of measurements from influential 

vehicles for all pollutants, as documented in detail in the report.6 The sensitivity analyses 

showed that the magnitude and the statistical significance of the results were not impacted and 

thus demonstrated that the results are statistically robust.

When modeling the covariance structure, the first-order autoregressive structure was 

selected. Although we acknowledged in the report that the spatial covariance structure did not 

converge, we demonstrated that the selected first-order autoregressive structure is superior to the 

compound symmetry matrix. Furthermore, as stated in the report, we expect the estimates of 

fixed effects (i.e., the differences in mean emissions between high and low sulfur fuel) to be the 

same for different covariance structures, differing only in the standard errors of these estimates. 

The peer-reviewers also supported our methodology by stating that “the autoregressive 

covariance structure is appropriate.”7

Regarding emissions concentration measurements taken from Bags 2 and 3, manufacturer 

specifications for analyzer performance are given in Appendix C of the test program report. 

However, these are relatively general and do not provide the level of detail that is useful to 

address the issue of error introduced by very low measurements. To address the increased level 

of (relative) uncertainty in very low measurements, we performed the sensitivity analyses 

discussed in Section 7.3 of the report. These exercises suggested that the overall results of the 

program changed very little when very low-emitting vehicles or zero-emission observations were 

removed from the dataset. 

With respect to the comment on the presentation of the results from in-use sulfur program 

in terms of percentages, as the commenter points out, it is a widely accepted method for analysis 

of log-transformed data. In addition, since the statistical analyses were performed on FTP 

 

5 The Presidential Memorandum is found at: http://www.whitehouse.gov/the-press-office/presidentialmemorandum-regarding-fuel-efficiency-standards.

6 The Effects of Ultra-Low Sulfur Gasoline on Emissions from Tier 2 Vehicles in the In-Use Fleet, EPA-420-R-14-

002.

7 The Presidential Memorandum is found at: http://www.whitehouse.gov/the-press-office/presidentialmemorandum-regarding-fuel-efficiency-standards.
Tier 3 Summary and Analysis of Comments

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composites, as well as each bag results, we do not believe that the effect of fuel sulfur on 

emissions is distorted in any way.

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

A second study used by EPA to support its 10 ppm sulfur proposal was the “MSAT (Mobile 

Source Air Toxics) Study”, conducted in 2005 with several automakers to examine the effects of 

sulfur and other fuel properties on nine Tier 2 vehicles. It is interesting to note that this study has 

not appeared in literature reviews of fuel effects on emissions including one of the most 

comprehensive reports, Coordinating Research Council (CRC) Report E-84 “Review of Prior 

Studies of Fuel Effects on Vehicle Emissions” published in August 2008. Several of the 

participating MSAT Study automakers are also members of CRC. 

The fuel set used in this study was limited and not well designed. It relied upon a base fuel to 

which butane, benzene, and sulfur were sequentially added to produce the three main test fuels. 

Sulfur levels were 6 ppm for the base fuel and 32 ppm for the sulfur-doped 

base+butane+benzene fuel. 

The 2005 MSAT study utilized Tier 2 vehicles and examined sulfur effects (6 versus 32 ppm) 

with an unrealistic sulfur loading cycle for the 32 ppm fuel (3 hour cruise at 35 mph). 

The Tier 3 Draft Regulatory Impact Analysis (DRIA) provides the following short discussion of 

the MSAT Study: “In 2005 EPA and several automakers jointly conducted a program that 

examined the effects of sulfur and other gasoline properties, benzene, and volatility on emissions 

from a fleet of nine Tier 2 compliant vehicles, the “MSAT (Mobile Source Air Toxics) Study. 

Reductions for FTP-weighted emissions for the sulfur changes in this program were 33 percent 

for NOx, 11 percent for THC, 17 percent for CO, and 32 percent for methane. Given the prep 

procedures related to catalyst clean-out and loading, these results may represent a “best case” 

scenario that magnifies what would be expected under more typical driving conditions. 

Nonetheless, these data suggested the effect of sulfur loading was reversible for Tier 2 vehicles, 

and that there were likely to be significant emission reductions possible with further reductions 

in gasoline sulfur level.” 

Having reviewed the publicly available documentation on the above program, we find the details 

to be very limited. The vehicles are noted to be from model years 2004-2007 meeting the Tier 2 

Bin 5 or Bin 8 emissions standards. At this point, without a list of vehicles tested, we have no 

knowledge of the range of technologies tested, but given the model year information, this 

suggests that manufacturers provided some pre-production vehicles for this 2005 test program. In 

addition, these vehicles would likely not meet Tier 3 emission levels based on their Tier 2 Bin 

designations. 

EPA indicates that “Given the prep procedures related to catalyst clean-out and loading, these 

results may represent a “best case” scenario that magnifies what would be expected under more 

typical driving conditions”, but the prep test procedure for sulfur loading is unrealistic as defined 

in the MSAT RIA “Where a sulfur loading prep was indicated, a 3-hour 35 mph cruise was 
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conducted immediately before the final drain and fill. The purpose of this prep procedure was to 

equilibrate the catalyst with higher sulfur fuel, simulating conservatively the conditions that 

might occur in typical suburban driving” (5). No data were presented to indicate equilibration of 

emissions before or after the sulfur clean-out and loading procedures. 

Further expanding on the above point, an independent review of the MSAT study noted that the 

use of different preconditioning cycles between the tests on the high and low sulfur fuels “...will 

impact sulfur loading, and this makes the conclusions with respect to sulfur impact highly 

questionable”. 

Without individual vehicle data we are constrained in our ability to provide informed comment 

neither on the statistical analysis of this program nor on the impact of individual vehicles on the 

overall fleet response. However, we note that EPA recognized the limited nature of this work in 

its closing comments on the test program as described in Chapter 6 of the RIA for the MSAT2 

rulemaking: “Clearly the data from this scoping study indicate that there may be benefits to 

future fuel controls, though in many cases the size of the test program was not sufficient to 

determine effects with statistical confidence. At this time, EPA is hoping to conduct a more 

comprehensive fuel effects test program, as directed by the Energy Policy Act of 2005, “in 

cooperation with stakeholders and other interested parties, to generate new data over the next 

several years. We expect that work will produce updated emissions models, as well as sufficient 

data to make decisions about future fuels programs.” 

Marathon Petroleum Company LP (MPC)

-The 2005 MSAT study utilized Tier 2 vehicles and examined sulfur effects (6 versus 32 ppm) 

with an unrealistic sulfur loading cycle for the 32 ppm fuel (3 hour cruise at 35 mph) 

Our Response:

The MSAT study was published by EPA as part of the MSAT2 rulemaking package. It 

was not published separately within peer reviewed literature although it was subject to public 

comment as part of MSAT2. Regarding the fuel set used in the study, this “one-dimensional” 

fuel design was reasonable given the scope of the study. The fuel effect most relevant to Tier 3, 

that of sulfur, was produced by adding a tiny amount of doping agent to the fuel that resulted in a 

negligible change to the other fuel properties. Thus an A-B comparison between the doped and 

undoped fuels provides a good assessment of emission impacts of sulfur.

With respect to other comments regarding the MSAT Study, EPA would like to clarify 

that the MSAT study was merely a scoping program intended to confirm the magnitude of 

certain fuel effects (benzene) and examine the potential range of certain others (sulfur) using Tier 

2 vehicles. The program is mentioned in Sections III.A.2 and IV.A.6 of the preamble as 

corroborating evidence of sulfur effects of significant magnitude, though the actual percentage of 

the effects from the MSAT study were not used for inventory or benefits calculations (e.g., in the 

MOVES model) within the Tier 3 Rule. The need for a larger vehicle fleet and a more 

representative mileage accumulation approach was discussed in the background of the EPA In-
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Use Sulfur Study, which has served as the primary source of EPA’s data on in-use impacts of 

gasoline sulfur under the Tier 3 program.

EPAct/V2/E-89 Study

What Commenters Said:

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

The EPAct/V2/E-89 program did not look at sulfur effects (sulfur at 25 ppm). Instead, EPA 

determined Tier 2 vehicle-fuel effects for 5 fuel properties: aromatics, ethanol content, RVP, T50 

and T90. To determine sulfur effects, EPA then used a separate program (in-use fleet test) to 

adjust for fuel sulfur sensitivity. 

The EPAct/V2/E-89 gasoline fuel effects study resulted in a new fuel/emissions equation for 

intended use in MOVES. This comprehensive assessment evaluated independent fuel effects on 

fifteen MY2008 vehicles meeting Tier2 Bin5 standards. A statistically optimal study design was 

developed to represent 5 fuel properties: aromatics, ethanol content, RVP, T50 and T90. These 

properties were selected based on previous studies as having potential exhaust emissions 

impacts. It is acknowledged that “sulfur also affects emissions but due to its impact on vehicle 

catalyst, it is necessary to assess the effects of sulfur separately from those of other fuel 

properties.” 

While the EPAct assessment is a detailed document on the experimental design, test procedure 

development, and fuel effects summary, a key missing component is the reduction in sulfur as 

proposed in this rulemaking. All test fuels, which were evaluated within the EPAct test program

contained sulfur levels of 25 +/-5 ppm, thus the robust fuel effects equation that was developed 

based on statistical analysis of the study data has no sensitivity to sulfur. 

Fuel effects, as developed by EPA from the EPAct data, differ in some cases from published 

studies; 

The EPAct Program vehicle test fleet is not representative of the in-use vehicle fleet; 

The EPAct Program was not large enough to provide the data needed to resolve non-linear fuel 

effects;

EPA’s statistical analysis of the EPAct Program data does not address application of results to 

in-use conditions; 

Very low emission values observed from some vehicles create problems with the statistical 

analysis;

Mathematical relationships relating fuel properties to emissions of some pollutants are too 

complex and the quadratic form used by EPA is not optimal; and

The specific mathematical form chosen by EPA is not clearly superior to alternatives that 

provide significantly different effects when tested on commercial fuels projected by EPA for 

2030. [EPA-HQ-OAR-2011-0135-4276-A2.pdf, p. 19]
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Marathon Petroleum Company LP (MPC)

The EPAct/V2/E-89 program did not look at sulfur effects (sulfur at 25 ppm). Instead, EPA 

determined Tier 2 vehicle-fuel effects for 5 fuel properties: aromatics, ethanol content, RVP, T50 

and T90. To determine sulfur effects, EPA then used a separate program (in-use fleet test) to 

adjust for fuel sulfur sensitivity 

Our Response:

While effects of fuel sulfur levels were not evaluated in the EPAct program, the large Inuse sulfur test program specifically addressed fuel sulfur effects on similar Tier 2 vehicle models 

and included many cleaner and “Tier 3 like” vehicles. This dual approach was adopted because it 

is not feasible to assess the effects of sulfur and other properties simultaneously, as the complex 

behavior of sulfur can be expected to confound the effects of other properties during the course 

of a study. Accordingly, the In-use sulfur test program was designed to examine the effects of 

sulfur including the storage and release behavior of the catalyst. Accounting for this behavior 

requires a different study design than that used to assess the non-sulfur properties. For example, 

in studying sulfur effects, it is critical to account for driving history and to apply specific 

preconditioning procedures that differ from those applicable to other fuel effects. 

With respect to the comment that “fuel effects ... differ in some cases from published 

studies,” it is not surprising that EPAct results differ from those in other studies. Emissions are 

sensitive to many details of how fuels are blended and how testing is conducted. In addition, 

calibration strategies implemented differently by different vehicle manufacturers can cause 

significant differences in fuel effects across vehicles. Invariably, studies are published based on 

a wide variety of designs and procedures. The EPAct program used a large and representative 

test fleet (15 high-sales vehicles) along with fuel blending and vehicle testing conducted by 

experts to produce the highest quality data possible. More details on program design and data 

analysis are available in the EPAct/V2/E-89 program reports available at 

http://www.epa.gov/otaq/models/moves/epact.htm.

To address this comment in its original context, we make reference to the technical 

analysis underlying it, appended to the API comments as Attachment 13.8

On this topic, the subsection begins with reference to a summary of results in a recent 

literature review (CRC E-84).9The overall approach in the E-84 report is to treat each fuel 

property piecemeal, rather than in an integrated fashion. For example, in the chapter covering 

“Aromatics and Benzene,” test fuels and emissions differences are presented in terms of 

differences in aromatics levels, and interpreted as though attributable to aromatics differences. 

Similarly, in the chapter on “Vapor Pressure” effects, emissions differences in cited results are 

discussed primarily solely in terms of RVP, with minimal reference to other fuel effects. In 

addition, for all studies cited, results appear to be presented in terms of cycle aggregates, in 

 

8

Sierra Research, Inc. Assessment of the Emission Benefits of the U.S. EPA’s Proposed Tier 3 Motor Vehicle 

Emission and Fuel Standards. SR2013-06-01. Sacramento, CA. June 23, 2013.

9 Hochhauser, A.M. Review of Prior Studies of Fuel Effects on Vehicle Emissions. CRC E-84. Coordinating 

Research Council, Alpharetta, Georgia. August, 2008.
Tier 3 Summary and Analysis of Comments

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which start and running emissions are averaged. This approach complicates simple comparisons 

to the models derived from EPAct, which evaluated cold-start and hot-running emissions 

separately, but did not attempt to combine or aggregate them. 

To a large degree, the comparisons to previous studies show a basic misunderstanding of 

what the EPAct model coefficients represent. As emphasized in the EPAct report, a model 

coefficient for a given property, e.g., “aromatics,” does not represent “the effect of aromatics on 

emissions,” but rather the effect of varying aromatics on emissions if the remaining four 

properties were held constant. In reading Attachment 13, it appears that in most cases, the 

comparisons listed are made by comparing single EPAct model coefficients to percent 

differences obtained by averaging results across sets of fuel blends. However, in such “wholeblend” results, differences observed reflect changes in all properties of the fuels, not only the 

single property under consideration. 

These considerations complicate attempts to make simplistic comparisons between 

EPAct model coefficients and the averaged results of most fuels studies, which involve 

measurements of small numbers of vehicles on sets of fuels in which selected properties are 

modified, but without the intensive experimental design incorporated into programs such as 

EPAct or the Auto/Oil study.

Nonetheless, despite these caveats, the studies summarized in E-84 appear broadly 

consistent with EPAct in terms of aromatics effects on HC and CO. The chapter covering 

aromatics effects for gasoline cites approximately 14 studies reporting HC or CO results, varying 

greatly in scope and design, of which over half reported that reducing aromatics reduced HC and 

CO (or both), with the remainder reporting mixed results or no effects. For the studies reporting 

effects, these findings are generally consistent with the EPAct coefficients for aromatics, if we 

assume that the cycle aggregates reported are dominated by cold-start emissions, for which the 

EPAct aromatics coefficients are positive (i.e., reducing aromatics reduces emissions and vice 

versa).

With respect to NOx, results are mixed. We disagree, however, with the conclusion that 

the results obtained in EPAct are uniformly inconsistent with previous results. At the outset, it is 

important to note that the three sets of analogous models produced prior to EPAct, namely, the 

Complex model, the ARB predictive model, and the EPA predictive model, all have positive 

main-effects aromatics coefficients for NOx. 

In addition, in contrast to most studies, the design for the EPAct study is well balanced 

between the two aromatics levels studied and the levels of the four remaining properties. When 

the results are averaged by vehicle and by fuel properties, the results suggest a notable increase 

in NOx for most vehicles, as shown in the figures below. For example, in Figure 1, which shows 

cold-start (Bag 1) NOx results averaged by vehicle and aromatics level, 13 of 15 vehicles show 

higher NOx at the higher aromatics level, with the remaining two vehicles showing no obvious 

change. This effect is also clearly visible when the results are averaged by the two aromatics 

levels and the levels of any of the four remaining fuel properties. Results are similar but not 

identical for hot-running (Bag 2) results shown in Figure 2. For running emissions, behavior by 

vehicle is more complex, with six of the vehicles showing a decline or no change by aromatics 
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level, but with the remaining vehicles showing increases. While this set of results suggests an 

increase in NOx on average, it also shows variability in vehicle responses, which may be 

attributable in some degree to measurement or random error, or also to differences in vehicle 

design, calibration or emission-control strategies. 

Figure 1. Cold-start NOx results for the EPAct Phase-3 Program, averaged by Aromatics 

Level (vol.%) and by Vehicle.
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Figure 2. Hot-Running NOx results for the EPAct Phase-3 Program, averaged by 

Aromatics Level (vol.%) and by Vehicle.

Attachment 13 also notes that according to the studies cited in E-84, reducing RVP generally 

reduced HC emissions (i.e., NMHC), whereas the EPAct models suggest the opposite effect, i.e., 

the main-effects RVP coefficients are negative for both start and running emissions. We hold 

that the coefficients for the HC and CO models are consistent with each other, and with 

engineering judgment. However, in this context it is important to reemphasize that the 

coefficient represents a change in emissions associated with a fuel property, if all others are held 

constant.

The negative RVP coefficient for start emissions suggests that, other fuel properties held 

constant, a less volatile fuel burns less efficiently under start conditions, resulting in emission of 

more partially burned and unburned HC, hence elevated HC emissions. The negative coefficient 

for running emissions may appear less intuitive at first glance, unless we recall that increasing 

RVP while holding the remaining properties constant would require addition of heavier 

components to prevent shifts in T50 and T90. The predicted increase in emissions would be 

associated with a change in RVP, but probably attributable to the changes in other properties.
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While keeping this caveat in mind, however, if concurrent changes in RVP and T50 are 

viewed jointly, the fact that the EPAct coefficients for RVP and T50 are opposite in sign is also 

internally consistent and easily understood. The interpretation is that heavier, less volatile fuels 

(T50 increasing, RVP decreasing) tend to burn less cleanly than lighter, more volatile fuels (T50 

decreasing, RVP increasing).

Attachment 13 notes the “mixed effects” for CO, i.e., that the linear coefficients for T50 

are negative for cold-start emissions but positive for hot-running emissions. For start emissions, 

the negative coefficient for T50 is consistent with the positive coefficient for HC, meaning that 

because heavier fuels emit more unburned and partially burned hydrocarbons, they emit less CO. 

However, during hot running operation, the situation is somewhat different. Under stabilized 

conditions, heavier fuels burn somewhat less efficiently, but unlike start conditions, this reduced 

efficiency manifests through increases in both HC and CO.

Commenting on previous fuel-effects models, Attachment 13 notes that the linear effect 

HC coefficient for RVP is positive for the Complex and Predictive models, and negative for the 

EPAct models. This may be explained by differences in technology between the Tier-0 and Tier1 vehicles underlying the Complex and Predictive models, and the Tier 2 vehicles underlying the 

EPAct models. For example, improvements in air/fuel ratio control during fuel tank evaporative 

canister purge, as well as the relative contributions of cold-start versus warmed-up operating 

modes to test cycle composite results, could cause a shift in the primary impact of fuel volatility 

on exhaust HC emissions. 

Finally, with respect to particulate emissions, Attachment 13 notes that “It has been well 

established that adding oxygenates to diesel fuel generally reduces PM emissions, which makes 

the finding that oxygenates increase PM in gasoline vehicles interesting...” (page 36). This 

conclusion reflects a misinterpretation of the EPAct coefficients, as mentioned above. The fact 

that the linear coefficients for ethanol for the PM models are positive does not imply that the 

model suggests that “oxygenates increase PM in gasoline vehicles.” What the coefficients do 

mean is that if ethanol is blended into gasoline with the four remaining properties held constant, 

the increase in ethanol concentration by itself would be associated with an increase in PM. 

Changes in the other fuel parameters that result from addition of ethanol also have to be taken 

into consideration when assessing the potential impacts on PM. Furthermore, the model does not 

necessarily show that the increase in ethanol causes the increase in PM. The impacts on PM may 

be due to interactions of ethanol with other fuel properties or components. 

With respect to the comment that the EPAct Program was not large enough to provide the 

data needed to resolve non-linear fuel effects, the commenter’s Attachment 13 notes that “... 

aggregated datasets are not necessarily superior to a single well-designed dataset ...” and that 

“... it is very difficult to resolve a large number of non-linear fuel terms in a single program 

design... . Given the limited number of fuels in the EPAct study, ... it is not clear that nonlinear effects can be properly resolved. ...”
Tier 3 Summary and Analysis of Comments

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We agree with the first comment and disagree strongly with the second and third. On the 

contrary, we argue that for analyses of fuel effects, which tend to be tightly correlated, use of a 

single coherent dataset reflecting a well-designed experiment is superior to meta-analyses 

involving the combination of multiple datasets embodying differing designs (or no design). One 

reason for preferring a single experimental dataset is that it allows the incorporation of vehicle as 

a “blocking variable.” A dataset including measurements for all fuels on each vehicle, in effect 

replicating the experiment on each vehicle, allows variability due to vehicle differences to be 

isolated from the fuel effects of interest. This feature is a major advantage, as the vast majority 

of variability in any such dataset is contributed by vehicles, rather than by fuels. 

The third comment is simply an unsubstantiated assertion. The EPAct design was 

produced by a competent and experienced statistician with lengthy experience working in the 

field of automotive and fuel emissions. The fuel set was accordingly designed using state-of-theart methods to allow characterization of two quadratic terms and four interaction terms. Granted, 

as the use of classic factorials in estimation of fuel effects is not practical, the generation of an 

optimal design required that these six effects be specified in advance, based on prior knowledge 

of fuel effects. While it is not necessarily impossible to estimate additional effects not included 

in the design, doing so requires caution. For this reason, we elected to retain models including 

only subsets of the 11 terms included in the original design. Aside from other considerations, we 

believe these two reasons are sufficient to rely on a single well-designed experiment to estimate 

fuel effects. In addition, an independent peer review of the draft analysis report did not raise any 

significant concerns with the methods used to produce the final models.10

With respect to the comment that EPA’s statistical analysis of the EPAct Program data 

does not address application of results to in-use conditions, the statistical analysis for EPAct 

focused on producing the most robust findings possible from the test program itself. We 

consider the assertion in Attachment 13 that “important questions about the applicability of the 

results to the modeling of in-use vehicle emissions ... are not discussed ... include[ing] the 

overall representativeness of the database to in-use vehicles and fuels...” to be unfounded. 

During the design of the project, the vehicle sample was specifically and carefully designed to 

cover the majority of vehicle sales for Tier-2 vehicles at the time (MY2008). In addition, the 

fuel set was designed to span the fuel properties of 95% of summer fuels on the market, based on 

current AAM fuel survey results.

With respect to the comment that “very low emission values observed from some 

vehicles create problems with the statistical analysis”, it would be more correct to say that 

“censored” or “missing” measurements created issues in analysis, and that vehicles with “very 

low” measurements were more likely to have values censored by limitations in the measurement 

techniques. The issue of censored measurements and discussion of dilution and background 

contamination as causal factors is thoroughly discussed in the project report. In addition, the 

issue of censoring was addressed in analysis through the application of widely-accepted standard 

 

10 Four Peer Reviews Supporting Tier3: EPAct Analysis Draft Report. U.S. Environmental Protection Agency, 

Washington, D.C. Related documents are available at 

http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=240069.
Chapter 4: Proposed Vehicle Emissions Program

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techniques, methods that were deemed appropriate by the peer reviewers.11 Results from this 

program have advanced our knowledge base of best practices related to measurement.

API also commented that “mathematical relationships relating fuel properties to 

emissions of some pollutants are too complex and the quadratic form used by EPA is not 

optimal” and that “the specific mathematical form chosen by EPA is not clearly superior to 

alternatives...”. The text in Attachment 13 (page 44) notes that some EPAct models are more 

complex than others. If we take “more complex” to mean “more terms” it is clear that the 

observation is correct but the commenter gives no indication of how we can know when a model 

is “too complex.” As we make clear in the project report, the model-fitting process was 

conducted so as to develop reduced models that contained no more terms than necessary to 

achieve the best possible fit to the data, that is, were as simple as possible. An outcome of this 

process was that models for hydrocarbons contained more terms than those for NOx and PM. 

We have no technical basis on which to question this result. We can note, however, that on the 

same page, Attachment 13 cites the recommendation of the DOE/NREL report that “the 

complete fuels model” be used. As the complete (i.e., full) models contain all possible terms, this 

citation appears to contradict the comment that the reduced models used are “too complex.”

Under this heading, Attachment 13 also takes issue with the inclusion of quadratic terms 

in the EPAct models, citing this form as “not optimal.” On this point, we note that first, linear 

models with the inclusion of quadratic terms have been used in development of predictive 

models to date, including the Complex and Predictive models. Second, for EPAct, the 

experimental design of the fuel set was based on a specified model including quadratic terms for 

ethanol and T50. The design was reviewed by several fuel and emissions experts from the 

automotive and petroleum industries, who did not raise similar questions about the proposed 

model structure during the design phase. Third, it is improbable that given limitations in time and 

budget, a sufficient number of experimental test points could have been included (and the 

required fuels blended) to fit a more complex deterministic form, even had such a form been 

proposed. Fourth, given the empirical, rather than theoretical approach to study design, it is not 

clear that a more complex deterministic form would have given better results. 

Finally, we can add that due to the application of hierarchy in model fitting, quadratic (or 

interaction) terms are included only when the associated linear terms are also included. So, the 

relevant unit to consider is not the quadratic term in isolation, but the linear and quadratic terms 

taken together. The actual shape described by these two terms depends on their signs and the 

sizes of the coefficients relative to each other. The second-order term is included only when it 

improves fit and is necessary to describe curvature in the data where it is apparent.

Other Studies on Gasoline Sulfur Effects on Emissions

What Commenters Said:

 

11 Sierra Research, Inc. Assessment of the Emission Benefits of the U.S. EPA’s Proposed Tier 3 Motor Vehicle 

Emission and Fuel Standards. SR2013-06-01. Sacramento, CA. June 23, 2013.
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American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

EPA relies either on older vehicle studies designed to address different issues at the time or on 

data generated from vehicles tested on fuels containing sulfur levels outside of the 10 to 30 ppm 

range. For this proposal, the Agency makes numerous inaccurate assumptions and data 

interpolations that are well outside the scope of those earlier studies. Furthermore, EPA makes 

several assertions without supporting data. 

EPA tested very few “Tier 3 – like” vehicles and did not distinguish between the sulfur effects 

for these vehicles and those for older technology vehicles. 

The “Umicore” study used only one PZEV vehicle and the gasoline sulfur (3 versus 33 ppm) 

effects on emissions were confounded by changes in other fuel properties. 

One study, the “Umicore” study, looks at a single PZEV vehicle (2009 Chevrolet Malibu) 

operating on two fuels – a CARB Phase II Cert fuel at 33 ppm sulfur and a “zero-sulfur” EEELube certification fuel with 3 ppm sulfur. To infer any differences in NOx emissions between 10 

ppm and 30 ppm sulfur fuels from this work is beyond our capability, unless we assume linearity 

in NOx response to fuel sulfur levels. Confounding any NOx results from this limited sulfur 

study are the underlying base fuel properties that although not noted by the authors, we believe 

are different and therefore significantly impact the emissions results. Specifically, we believe 

there to be differences in distillation properties, chemical composition and oxygenates. The 

standard industry practice is to use sulfur dopants to avoid underlying base fuel changes 

impacting the emissions. We would also note that results from testing two fuels on a single 

vehicle do not provide much guidance on the potential impact of the proposed Tier 3 emissions 

regulations. In particular, the “Umicore” paper did not provide a statistical analysis to show 

whether the measurements made on the single vehicle tested were (a) statistically significant 

and/or (b) broadly characteristic of the underlying technology represented. These concerns as 

well as others regarding the Umicore study are further detailed in comments submitted by API to 

EPA Administrator Lisa P. Jackson on November 11, 2011 and available in the Docket for this 

proposed rule. 

EPA proceeds to provide additional support for the “insight” into the fuel sulfur impacts on “Tier 

3 like” vehicles by reviewing the data from the “Umicore” study (a single PZEV vehicle) which 

we’ve already discussed above. Thus it would appear that EPA lacks data on Tier 3 emission 

level vehicles at the sulfur levels of interest, namely between 10 ppm and 30 ppm, to fully 

understand and comment on the appropriate and necessary fuel sulfur levels to allow compliance 

with the Tier 3 emissions requirements. Proceeding to a formal decision without providing the 

underlying supporting data prevents informed public comment, is a departure from accepted 

scientific rigor and ultimately is a violation of the Administrative Procedures Act. 

There are many published studies evaluating the impacts of extremely low sulfur levels on 

vehicles, although, with the notable exception of the Umicore Study, these studies generally 

tested vehicles with emission levels higher than the proposed Tier 3 exhaust standard. Of all of 
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the available studies, the RIA and the In-Use sulfur study report address only two—MSAT and 

Umicore. EPA fails to explain why other available data were not included in its analysis, and the 

Agency clearly should have performed the most comprehensive analysis possible. It also needs 

to be stressed that even the two studies selected by EPA do not support the conclusions of EPA’s 

In-Use sulfur study or the proposed 10 ppm sulfur limit. As noted by the review conducted by 

Sierra Research, had EPA conducted a more robust analysis of sulfur effects using all of the 

existing data on late-model, low-emission vehicles, it would have likely observed significantly 

lower responses for pollutants such as NOx and HC than those seen in the EPA In-Use Study. 

MECA relies heavily on an SAE paper authored by Ball, Clark and Moser (Umicore) in 

attempting to rebut our argument that there are sulfur-insensitive automotive technologies 

available today that could be used to facilitate compliance with the proposed Tier 3 emissions 

standards without the need to reduce average gasoline sulfur content to 10 ppm. This SAE paper 

had reported measurements of the FTP NOx emissions response of a 2009 model year Chevy 

Malibu PZEV to test gasolines with sulfur contents of 3 ppm and 33 ppm.

In reply to MECA, we reiterate concerns which API and AFPM had raised in a critique of the 

Umicore SAE paper provided in our June 28, 2013 written comments on the Tier 3 NPRM and 

also in an earlier November 11, 2011 API response to the AAM proposal to cap gasoline sulfur 

content at 10 ppm. Specifically:

• The SAE paper fails to note the differences in the underlying properties of the base fuel used 

and how this may confound the results. Specifically, when comparing a CARB Phase II 

certification fuel (33 ppm sulfur) with a EEE-Lube certification gasoline fuel (“zero sulfur”), 

differences in distillation properties, chemical composition and oxygenates can impact emissions 

results. The standard industry practice is to use sulfur dopants to avoid underlying base fuel 

changes impacting the emissions.

• Results from testing two fuels on a single vehicle do not provide much guidance on the 

potential impact of fuel sulfur levels on the fleet of future Tier 3 vehicles. In particular, the 

Umicore paper did not provide a statistical analysis to show whether the measurements made on 

the single vehicle tested were (a) statistically significant and/or (b) broadly characteristic of the 

underlying technology represented.

Marathon Petroleum Company LP (MPC)

-There were very few ‘Tier 3 – like’ vehicles tested and EPA did not separate out the effects for 

these vehicles from older technology vehicles 

-The ‘Umicore’ study used only one PZEV vehicle and the sulfur effects (3 versus 33 ppm) were 

confounded by other base fuel property changes 

Manufacturers of Emission Controls Association (MECA)

Numerous published studies have documented fuel sulfur-related deactivation of three-way 

catalysts that are the primary exhaust emission control technology used on light-duty and 

medium-duty gasoline vehicles. The negative impacts of gasoline fuel sulfur content on catalytic 
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emission controls are highlighted in a newly revised MECA report: “The Impact of Gasoline 

Fuel Sulfur on Catalytic Emission Control Systems” (available on MECA’s website, 

www.meca.org, under Resources >> Reports).

EPA has released a thorough and well-designed sulfur effects study on 81 in-use Tier 2 lightduty gasoline vehicles that clearly showed significant reductions in criteria pollutants in 

comparing emissions performance on gasoline with 28 ppm sulfur versus 5 ppm sulfur. Work 

published in a 2011 SAE technical paper (SAE paper no. 2011-01-0300) shows similar, 

significant emission benefits on a 2009 model year PZEV vehicle operated with 3 ppm sulfur 

gasoline versus 33 ppm sulfur gasoline. In this gasoline sulfur effects study, on a 2009 PZEV 

passenger car, the results clearly show that the underfloor converter used on the close-coupled + 

underfloor PZEV catalytic converter system was susceptible to sulfur-related performance 

degradation due to its cooler operating temperatures during the FTP test cycle using a 33 ppm 

sulfur-containing gasoline. The loss in NOx performance of this underfloor PZEV converter in 

successive FTP tests could be recovered to some extent, or avoided to a large degree, by either 

purging stored sulfur off the underfloor converter with the use of a higher speed and load test 

cycle (i.e., the US06 test cycle) sandwiched between FTP tests, or using a gasoline with 

significantly lower sulfur levels (i.e., a 3 ppm sulfur-containing gasoline).

In a MECA study published in a 2007 SAE paper (SAE paper no. 2007-01-1261), an advanced 

three-way catalyst system installed on a large 2006 V8-powered SUV showed clear evidence of 

sulfur deactivation in successive FTP testing with aged catalysts using 17 ppm sulfur gasoline. 

FTP emissions for this full-size SUV started at the proposed Tier 3, Bin 50 levels and increased 

to slightly above proposed Bin 70 levels by the third FTP test, an emissions increase of more 

than 80% over three FTP tests. Sulfur deactivation of three-way catalysts negatively impacts the 

active precious metal catalysts, oxygen storage materials, and other activity promoters found in 

these sophisticated catalysts. The coverage and negative impacts of sulfur poisons on a three-way 

catalyst depends, in part, on the temperature history of the catalytic converter(s) found on the 

vehicle. Fuel sulfur deactivation of three-way catalyst is most apparent at lower exhaust 

temperatures (e.g., catalyst temperatures of less than about 500 degrees C). Sulfur deactivation of 

catalysts can be reversed to some degree by exposing catalysts to higher exhaust temperatures. 

Exhaust temperatures are expected to cool in the future as manufacturers reduce vehicle waste 

heat to meet future vehicle fuel efficiency/greenhouse gas standards. These cooler catalytic 

converter operating temperatures cause catalysts to accumulate higher amounts of sulfur poisons 

with today’s gasoline sulfur levels, resulting in higher emission levels of pollutants at the 

tailpipe, including ozone-forming exhaust pollutants like hydrocarbons and NOx. Ultra-low 

gasoline sulfur levels of 10 ppm on average are needed to ensure that manufacturers will be able 

to meet the proposed Tier 3, Bin 30 fleet average emission standards over their 150,000-mile 

useful life for the full range of light-duty vehicles that consumers wish to buy and manufacturers 

want to produce.

Work authored by Umicore in a 2011 Society of Automotive Engineers Technical Paper shows 

similar significant emission benefits on a 2000 model year PZEV vehicle, operated with three 

ppm sulfur gasoline versus 33 ppm sulfur gasoline. In a MECA study published in a 2007 SAE 

paper, an advanced three-way catalyst system installed on a large V-8 powered SUV showed 

clear evidence of sulfur deactivation and successive FTP testing with aged catalysts using 17 
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ppm sulfur gasoline. FTP emissions for this full-size SUV started at the proposed Tier 3, Bin 50 

levels, and increased to slightly above proposed Bin 70 levels by the third FTP test, and 

emissions increased more than 80 percent over three FTP tests. Sulfur deactivation of three-way 

catalysts negatively impacts the active precious metal catalysts, oxygen storage materials, and 

other activity promoters found in these sophisticated catalysts. The coverage and negative 

impacts of sulfur poisons on three-way catalysts depends in part on the temperature history of the 

catalytic converters found on the vehicle. Exhaust temperatures are expected to cool in the 

future as manufacturers reduce vehicle waste heat to meet future vehicle fuel efficiency and 

greenhouse gas standards.

Our Response:

EPA evaluated every applicable previous study regarding gasoline sulfur impacts on 

exhaust emissions known to us and we concluded that they were predominantly studies of preTier 2/LEV I vehicles with a very limited sample of LEV II or later vehicles. We determined that 

the extensive EPA in-use sulfur study, which for the FRM has been supplemented with 

additional vehicles representing “Tier-3-like” emissions levels, is the largest and most 

representative data set of newer and cleaner vehicles albeit still dominated by current Tier 2 and 

LEV II vehicles. In response to API comments that the in-use study did not represent future 

vehicles not yet in production, EPA and a large manufacturer, Ford Motor Company, performed 

sulfur testing on Tier 3 prototype vehicles representing the high volume and challenging LDT3/4 

light duty trucks designed to meet the cleanest Tier 3 emission levels that have not previously 

been included in any previous studies. Further, in response to API criticism of the original 

Umicore study fuel differences, we repeated the Umicore study using the exact same vehicle 

with a common base fuel at two sulfur levels, eliminating any doubt that the effects observed 

were from anything other than gasoline sulfur. The increase in NOx emissions with increased 

gasoline sulfur was approximately double that found in the original Ball/Umicore study. 

Additional testing was also performed on other “Tier 3 like” vehicles with similar results. The 

results can be found in the Preamble IV.A.6.d and RIA chapter 1sulfur feasibility discussions. 

Based on the new testing performed by EPA and data provided by Ford Motor Company on 

“Tier-3-like” low emission vehicles at full useful life and meeting Bin 50 emissions or lower, the 

percentage change in NMOG+NOx when going from 30 ppm S to 10 ppm S is much larger than 

the overall results we reported from the In-Use Sulfur study in the NPRM. We agree entirely 

with MECA’s comments and the papers and report cited by MECA are also referenced and cited 

within the RIA and within Preamble IV.A.6. 

We disagree that the extensive in-use sulfur study supplemented with cleaner Tier 2 

vehicles, the repeat of the Umicore study on a high volume passenger vehicle and the testing of 

Tier 3 prototype vehicles does not properly support our analysis of the impact of sulfur levels 

above 10 ppm. In fact, we believe that sulfur levels above 10 ppm on future vehicles designed to 

meet the new GHG standards may result in a larger negative impact as these more efficient 

vehicles will have less opportunity to prevent sulfur accumulation in the catalyst. Such an 

assessment of light-duty vehicles subject to the 2017-2025 GHG standards is also supported by 

comments from Alliance and Global Automakers, Honda and MECA.
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Data from SGS provided by API also shows an emissions benefit for reducing gasoline 

sulfur although the SGS testing alone is insufficient to determine feasibility of compliance with 

the Bin 30 fleet-average exhaust emission standards. Testing by SGS was conducted entirely on 

smaller mid-size and compact light-duty vehicles. More than one-half of light-duty vehicle sales 

in the U.S. are for light-duty trucks. The procedures used by SGS for rapid thermal aging of the 

catalysts also did not follow standardized EPA procedures or current industry practices and thus 

the exhaust emissions tests are not representative of full-useful-life emissions on the tested 

vehicles.12 The comments of the Alliance and Global Automakers regarding the difficulty of 

bringing light-trucks into compliance with Tier 3 exhaust emission standards in the absence of 

further gasoline sulfur control were in complete agreement with EPA’s engineering assessment 

within the draft RIA and the final Tier 3 RIA. Neither API, AFPM, nor MPC cited or provided 

any data on gasoline sulfur impacts on the full range of vehicles, including light-duty trucks, 

subject to the Tier 3 program and the Tier 3 Bin 30 fleet average exhaust emissions standard.

Sulfur Reversibility

What Commenters Said:

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM) and Marathon Petroleum Company LP (MPC)

Sulfur’s impact on catalysts is reversible, delaying rule implementation will not prevent vehicles 

from meeting the Tier 3 standards throughout their useful life. 

As explained above, January 1, 2017 implementation of the 10 ppm gasoline sulfur requirement 

is not necessary to enable vehicles to meet the NMOG + NOx standards. But, even if it is true as 

EPA claims that sulfur will negatively impact catalyst performance on such vehicles, that does 

not justify the January 1, 2017 implementation date, because the effect of sulfur on catalysts is 

reversible. A new study (described in detail in Section II.B of these comments) demonstrates that 

exposure to gasoline fuels containing sulfur levels of 80 ppm sulfur has no lasting impact on the 

performance of exhaust emission control systems on modern vehicles operated on 10 ppm sulfur 

gasoline. 

Our Response:

The observations from the In-use Sulfur study were that sulfur contamination is largely 

reversible on the Tier 2 vehicles included in the study. However, in order to reverse the sulfur 

contamination, a catalyst clean-out procedure involving very aggressive and high speed drive

cycles that push catalysts to thermal limits and sometimes into thermal protection modes were 

required. Excessive and unnecessary thermal cycling of the catalyst can cause premature 

deterioration. While a clean-out cycle largely returns the catalyst to a state of reduced emissions 

levels, subsequent mileage accumulation on the higher sulfur fuel will return the system to a 

contaminated state with elevated emission levels largely negating the emission reduction benefits 

 

12 For further details regarding SGS’s rapid thermal aging of exhaust catalysts, see the responses to “Current Tier 2 

Vehicles Can Comply with Tier 3 Standards Using Tier 2 Fuels” later in this sub-section.
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of the Tier 3 program. Further, some vehicles’ emission levels after the cleanout were still 

elevated on the high sulfur fuel compared with the emission levels following a clean-out with 

low sulfur fuel. Thus, while reversibility may lessen the total negative effects of higher sulfur 

fuel, it does not eliminate them. Vehicles will still run with elevated emissions until such time as 

the vehicle encounters the very aggressive and high speed driving that would facilitate sulfur 

removal from the catalyst. Depending on the driving habits of particular drivers, that type of 

cycle may occur only rarely or never. Further, even after clean-out some vehicles experience 

higher emission levels, and of course once the vehicle begins driving normally the emissions 

would again begin to rise. Moreover, as emissions are increased for vehicles in use as well as 

new vehicles, implementation of the 10 ppm requirement on January 1, 2017 will have 

immediate results in terms of reduced emissions. EPA does not have data on sulfur reversibility 

for vehicles in full compliance with the Tier 3 standards and post-2017 GHG standards. The 

Tier 3 standards include additional provisions that impact the ability to use commanded 

enrichment that previously facilitated sulfur removal during aggressive driving (see discussion of 

commanded enrichment in Preamble IV.A.6). The GHG standards are generally expected to 

reduce exhaust temperatures during in-use operation as vehicles become more efficient, resulting 

in increased sulfur contamination of active catalyst surfaces (see discussion in Preamble IV.A.6 

and response to comments regarding Gasoline Sulfur and GHG/Fuel Economy later in this subsection).

We discuss the implications of reversibility on lead time for sulfur reductions in Chapter 

5.1.1.3 of this document.

Gasoline Sulfur and Sulfur-tolerant Cold Start Emissions Control

What Commenters Said:

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

Sierra Research (10) recently conducted a comprehensive evaluation of the EPA’s technical 

justification for the proposed Tier 3 regulation as embodied in the emissions inventory estimates, 

air quality modeling, emission control and vehicle technology assessments, and related studies 

contained in the DRIA and in the public docket. A copy of the Sierra Research (hereinafter 

referenced as Sierra) study is attached, in its entirety, to these comments in Attachment No. 13 

In its review of EPA’s DRIA, Sierra noted a range of technologies available to the automakers 

that could be used to comply with the proposed rule, most of which would improve efficiency 

even in the absence of any sulfur changes (Draft RIA, p. 1-28). These include the following: 

- Increasing cell density;

- Using higher PGM loadings;

- Optimizing air fuel ratio control; and

- Limiting the amplitude of air fuel ratio excursions. 

EPA, however, did not assess the actual need for additional reductions in gasoline sulfur content 

in light of the emission control technology it expects automakers to deploy can be highlighted in 
Tier 3 Summary and Analysis of Comments

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more detail using data from Chapter 1.4.1.4 of the DRIA. This section deals with EPA’s 

assessment of technology improvements required for large light-duty trucks, which EPA notes 

“will be the most challenging light-duty vehicles to bring into compliance....” 

Figure 1-6 of the DRIA shows a number of technologies that EPA expects to be deployed in 

order to comply with the Tier 3 exhaust standard. EPA did not explicitly discuss the sulfur 

sensitivity of these technologies. However, based on the brief descriptions provided, it is 

reasonable to assume that the following technologies shown in Figure 1-6 will have little or no 

sensitivity to sulfur:

- Hydrocarbon adsorbers;

- Reduction in the thermal mass of catalyst substrates and exhaust system piping; and

- Secondary air injection 

EPA notes that “90% of NMOG emissions occur during the first 50 seconds after cold start,” and 

that “about 60% of the NOx emissions occur in these early seconds”. The three technologies 

listed above are designed to reduce or eliminate emissions that occur during the early period of 

operation, when the engine is cold and the catalyst has not yet reached operating temperature. If 

these technologies are employed to provide the bulk of the reduction necessary, then clearly the 

need for sulfur reduction is lessened. Unfortunately, it appears EPA did not consider or even 

discuss this possibility. These listed technologies are exclusive of changes in engine design that 

EPA expects could and would be made to achieve compliance, and which are also not sensitive 

to gasoline sulfur levels. 

Figure 2 [of EPA-HQ-OAR-2011-0135-4276] shows that if manufacturers could completely 

eliminate cold-start emissions, the current level of catalyst technology would allow compliance 

with the Tier 3 standards. Furthermore, given that cold-start emissions and cold-start emission 

control technologies are not likely to be very sulfur sensitive, little or no reduction in gasoline 

sulfur content should be required to achieve compliance. While it is unlikely to be able to 

eliminate this source of emissions fully, the table clearly shows that warmed-up emissions are 

already at a level that is compatible with the standard, which again calls into question the need 

for additional reduction in gasoline sulfur content and EPA’s arbitrary selection of the proposed 

10 ppm limit. Regardless, it is clear that EPA should have identified the possible emission 

control steps that are sulfur sensitive and those that are not sulfur sensitive, and evaluated 

whether 10 ppm sulfur was necessary and cost effective. 

MECA completely misses the point which API and AFPM were attempting to make with respect 

to the use of emission control technologies with lower sulfur sensitivity to reduce cold-start 

emissions in order to comply with the proposed Tier 3 standards. MECA asserts that API and 

AFPM “...assume that the use of three cold start emission control technologies [hydrocarbon 

adsorbers, reduced thermal mass substrates and exhaust piping, and secondary air injection] 

...could be used to completely eliminate cold-start emissions with today’s gasoline sulfur 

levels.” This assertion takes the API and AFPM comments completely out of context. If one 

were to read our comments in their entirety, one would note that we never stated that these three 

technologies had zero sulfur sensitivity, nor did we assume that they would be used to 

completely eliminate cold start emissions with today’s gasoline sulfur levels. Rather, we noted 

that cold-start technologies “are not likely to be very sulfur sensitive” and that “...if 
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manufacturers could completely eliminate cold-start emissions, the current level of catalyst 

technology would allow compliance with the Tier 3 standards” primarily because “warmed-up 

emissions are already at a level that is compatible with the standard.” A full rendition of our 

comments on this point follows (from p. 20 of our detailed comment submittal):

“The three technologies listed above are designed to reduce or eliminate emissions that occur 

during the early period of operation, when the engine is cold and the catalyst has not yet reached 

operating temperature. If these technologies are employed to provide the bulk of the reduction 

necessary, then clearly the need for sulfur reduction is lessened. Unfortunately, it appears EPA 

did not consider or even discuss this possibility. These listed technologies are exclusive of 

changes in engine design that EPA expects could and would be made to achieve compliance, and 

which are also not sensitive to gasoline sulfur levels.

Figure 2 shows that if manufacturers could completely eliminate cold-start emissions, the current 

level of catalyst technology would allow compliance with the Tier 3 standards. Furthermore, 

given that cold-start emissions and cold-start emission control technologies are not likely to be 

very sulfur sensitive, little or no reduction in gasoline sulfur content should be required to 

achieve compliance. While it is unlikely to be able to eliminate this source of emissions fully, the 

table clearly shows that warmed-up emissions are already at a level that is compatible with the 

standard, which again calls into question the need for additional reduction in gasoline sulfur 

content and EPA’s arbitrary selection of the proposed 10 ppm limit. Regardless, it is clear that 

EPA should have identified the possible emission control steps that are sulfur sensitive and those 

that are not sulfur sensitive, and evaluated whether 10 ppm sulfur was necessary and cost 

effective.”

Manufacturers of Emission Controls Association (MECA)

With respect to the need for a 10 ppm average sulfur gasoline standard, MECA has had the 

opportunity to review written Tier 3 comments submitted by the American Petroleum Institute 

(API) and the American Fuel & Petrochemical Manufacturers (AFPM). In these comments API 

and AFPM argue that EPA did not adequately justify the need for a 10 ppm average sulfur 

standard for gasoline in EPA’s Tier 3 proposal (API & AFPM Tier 3 comments dated June 28, 

2013). In their discussion of the technical need for lower gasoline sulfur levels, API and AFPM 

refer to three emission control technologies that target cold-start emissions on gasoline light-duty 

vehicles and that EPA noted in their Tier 3 Draft Regulatory Impact Analysis (DRIA) as 

technologies they expect to be deployed in order to comply with proposed Tier 3 exhaust 

standards. These three cold-start emission control technologies are hydrocarbon adsorbers, 

reduced thermal mass catalyst substrates and exhaust piping, and secondary air injection. API & 

AFPM make the statement in their comments that based on the description of these technologies 

provided by EPA in their DRIA, it is reasonable to assume that these technologies have little or 

no sensitivity to fuel sulfur levels. Using this assumption of no fuel sulfur sensitivity, API and 

AFPM then go onto to assume that these sulfur insensitive cold-start technologies could be used 

to completely eliminate cold-start emissions with today’s gasoline fuel sulfur levels. They then 

go on to show that with zero cold-start emissions of NMOG and NOx, typical warmed-up 

emissions are already at a level on light duty vehicles that would allow proposed Tier 3 

emissions of 30 mg/mile NMOG+NOx to be achieved with a 50% compliance margin without 
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4-89

the need for a lower gasoline sulfur level (Figure 2 in the detailed comments section of the API 

& AFPM, June 28, 2013 Tier 3 comments). 

This analysis of a Tier 3 compliance pathway that utilizes sulfur insensitive cold-start 

technologies is severely flawed in its initial assumption that cold-start technologies like 

hydrocarbon adsorbers, low thermal mass catalyst substrates/exhaust components, and secondary 

air injection are not sensitive to fuel sulfur levels. Each of these cold-start technologies still relies 

on a precious metal-based catalyst to oxidize hydrocarbons or reduce NOx, and these precious 

metal-based catalysts have well known sensitivities to fuel sulfur levels. Hydrocarbon adsorbers 

utilize zeolite-based materials to adsorb exhaust hydrocarbon constituents under relatively cold 

exhaust conditions and then release these stored hydrocarbon species at elevated exhaust 

temperatures. Once an adsorber releases these hydrocarbons back into the exhaust gas, a precious 

metal-based catalyst is required to oxidize these hydrocarbon species. The adsorber primarily 

functions as a temporary hydrocarbon “sponge” that provides time for the catalyst to heat-up and 

“activate” the catalytic oxidation reaction. The catalyst must “light-off” or activate to oxidize 

hydrocarbons during the cold-start portion of the emissions test cycle. There is an extensive body 

of literature that clearly shows that precious metal-based catalyst hydrocarbon light-off 

characteristics are negatively impacted by fuel sulfur levels. As sulfur accumulates on the active 

catalyst surface, the hydrocarbon light-off temperature increases. Hydrocarbon adsorber 

effectiveness in reducing cold-start hydrocarbon emissions is tied to the catalyst hydrocarbon 

light-off properties which, in turn, are impacted by fuel sulfur levels.

In a similar manner, cold-start technologies like low thermal mass substrates and secondary air 

injection help to accelerate the heat-up of the active catalyst but the catalyst is still the agent that 

facilitates the chemical reactions of hydrocarbon oxidation and reduction of NOx. Just as in the 

case of hydrocarbon adsorbers, the catalyst still needs to be activated or lit-off for the oxidation 

and reduction reactions to occur. Low thermal mass substrates or exhaust piping 3 and secondary 

air injection only impact the catalyst heat-up process. The catalyst still needs to accomplish the 

oxidation and reduction reactions and the catalyst activity/light-off temperature is impacted by 

fuel sulfur levels. An example of this sulfur dependence is found in SAE paper number 2013-01-

0300 (authored by Ball and Moser) that reports on the sulfur sensitivity of FTP NOx emissions 

using a 2009 model year Chevy Malibu PZEV vehicle. This Malibu PZEV vehicle utilizes 

secondary air injection and high cell density, low thermal mass substrates. Figure 11 of this 

paper summarizes the NOx FTP emission performance results for each portion of the test cycle: 

Bag 1 (cold-start), Bag 2 (warmed-up performance), and Bag 3 (hot start performance). For tests 

run with a 33 ppm sulfur gasoline, NOx emissions for each phase of the test cycle, including the 

cold-start portion of the test increased with each subsequent FTP test run with the vehicle (a total 

of three FTP tests run successively). Cold-start NOx emissions increased from 6.6 g/mi to 8.7 

g/mi to 9.2 g/mi over three FTP tests using 33 ppm sulfur gasoline – a 39% increase in NOx 

cold-start emissions for the third FTP test compared to the first FTP test. The use of secondary 

air and low thermal mass substrates did not make this vehicle insensitive to cold-start sulfur 

poisoning. In this case sulfur is accumulating on the available active catalyst surfaces and 

negatively impacting the catalysts’ cold-start NOx performance (and the catalysts’ NOx 

performance in the other two phases of the test cycle). Triplicate FTP tests run on this same 

PZEV vehicle using a 3 ppm sulfur gasoline did not show any negative Nox emission trends in 

the cold-start phase or any other phase of the test cycle. The negative impacts of sulfur on NOx 
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performance observed with the 33 ppm sulfur gasoline where also largely erased by running 

higher speed US06 test cycles between each FTP test. In this case, the higher speed operation of 

the vehicle between FTP testing creates higher catalyst temperatures that can purge sulfur that 

accumulates on the active catalysts during the cooler FTP test cycle.

MECA is unaware of any cold-start emission control technology that is not impacted by fuel 

sulfur levels since ultimately the cold-start emission performance is tied to the precious metalcontaining three-way catalyst performance. API’s and AFPM’s premise that cold-start emissions 

can be zeroed out by a sulfur insensitive technology has no basis in fact. As indicated in our 

earlier comments, MECA agrees with EPA’s assessment that a critically important element to 

ensuring that future gasoline vehicles will be able to comply with EPA’s proposed Tier 3 

emission limits is EPA’s proposed reduction of gasoline fuel sulfur levels to a 10 ppm national 

average starting in 2017. Numerous published studies have documented fuel sulfur-related 

deactivation of three-way catalysts that are the primary exhaust emission control technology used 

on light-duty and medium-duty gasoline vehicles. The negative impacts of gasoline fuel sulfur 

content on catalytic emission controls are highlighted in a newly revised MECA report: “The 

Impact of Gasoline Fuel Sulfur on Catalytic Emission Control Systems” (available on MECA’s 

public website, www.meca.org, under Resources >> Reports). This MECA gasoline fuel sulfur 

report includes the Toyota 2000 SAE paper reference that showed strong sulfur sensitivity on the 

emissions performance of a prototype SULEV vehicle that employed a close-coupled three-way 

catalyst and an underfloor converter that utilized a combination three-way catalyst plus 

hydrocarbon adsorber design. In their published test results both hydrocarbon and NOx FTP 

emissions increased significantly when the gasoline fuel sulfur level was increased from 8 ppm 

to 33 ppm (additional large increases in hydrocarbon and NOx FTP emissions were observed 

when the fuel sulfur level was increased to 150 ppm). The reference for this Toyota paper is SAE 

paper number 2000-01-2019. API and AFPM note in their comments that EPA neglected to 

include a reference for this work in their Tier 3 proposal.

Our Response:

EPA agrees with the comments submitted by MECA regarding cold-start emissions. 

EPA disagrees with the comments submitted by API and AFPM. The technologies listed by API 

and AFPM are not as suggested immune to the sulfur penalty. Thus, use of higher sulfur fuel in 

combination with these technologies will reduce their ability to control cold-start emissions. API 

and AFPM also ignore the engineering limitations within their analysis. For example, substrate 

cell density is limited by backpressure constraints. The amplitude of air/fuel ratio excursions is 

limited by control systems, feedback sensors and the design of the fuel injection system. The 

technologies described in the RIA to address cold start emissions also will not eliminate cold 

start emissions and largely do not reduce engine out emission levels. They are generally 

designed to allow the usage of the catalyst sooner following the cold start by increasing the 

catalyst temperature to more optimal levels earlier in the operation of the engine. As stated in 

MECA’s supplemental comments, all of these technologies ultimately rely on catalytic activity 

and thus all have performance that is negatively impacted by gasoline sulfur. It is important to 

note that the effect of sulfur is specifically on the catalyst’s ability to perform necessary 

functions at almost all temperatures including cold starts therefore the effect of sulfur will still be 

present during cold start even for these specific technologies. It is also well documented within 
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the literature cited in the preamble and RIA that gasoline sulfur directly increases PGM catalyst 

light-off temperatures (temperature at which the catalysts can effectively oxidize hydrocarbons 

and CO and reduce NOx). Additionally, the hydrocarbon adsorber ultimately also uses the 

catalyst when the hydrocarbons are later released into the catalyst therefore sulfur will ultimately 

also impact the effectiveness of this technology. Furthermore, hydrocarbon adsorbers do not 

contribute to reduction of cold-start NOx emissions and one of the technologies in the API and 

AFPM list, secondary air injection, can increase cold-start NOx emissions since lean excursions 

during air injection can result in an OSC oxidation state that is detrimental to NOx reduction 

reactions over the exhaust catalysts.

Finally, in order to meet the stringent Tier 3 NMOG+NOx standards, manufacturers will 

need to employ every available technology in some applications. To eliminate or reduce the 

effectiveness of a single technology, such as the exhaust catalyst, would result in the inability of 

certain vehicles to meet the standards.

Current Tier 2 Vehicles Can Comply with Tier 3 Standards Using Tier 2 Fuels

What Commenters Said:

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

In Table 1-1 of the Tier 3 DRIA, EPA demonstrates that lower gasoline sulfur levels are not 

necessary for compliance with the full useful life NMOG+NOx standard as the Tier 2 

certification fuel sulfur levels can vary from 15 to 80 ppm and yet there are a number of 2009 

model year vehicles that were already certified below the final 2025 standard of 30 mg/mi. 

Tables 1-1 and 1-2 demonstrate that there are a range of domestic and foreign vehicles sizes and 

types that already meet the 2022 NMOG+NOx standards by being below 50 mg/mi. 

EPA indicates that a number of 2009 MY Tier 2 vehicles easily meet the 2025 NMOG+NOx 

target of 30 mg/mi even when running on current cert fuel (15-80 ppm sulfur). 

As we’ve already shown, EPA’s own data indicate current vehicles can comply with the Tier 3 

standards even when using Tier 2 fuels. 

Marathon Petroleum Company LP (MPC)

EPA indicates that a number of 2009 MY Tier 2 vehicles easily meet the 2025 NMOG+NOx 

target of 30 mg/mi even when running on current cert fuel (15-80 ppm sulfur) 

Our Response:

The assessment in Table 1-1 of the Tier 3 DRIA simply reported our finding that a 

limited set of vehicle models are able to certify to the Tier 3 standards while operating on Tier 2 
Chapter 4: Proposed Vehicle Emissions Program

4-92

or LEV II certification fuels conceivably with sulfur levels above 10 ppm . While the allowed 

range of sulfur in current certification fuel can vary, we believe that typical certification fuel is 

blended at sulfur levels well below the current 30 ppm average. However, it cannot be 

concluded that all vehicles can achieve these low levels or meet the fleet average of 30 mg/mi 

with any sulfur level above 10 ppm. In fact, while certification emission levels seeming to 

comply with Tier 3 standards may be observed with some manufacturer’s current Tier 2 test 

vehicles, these vehicle models would be subject to in-use testing where they would be required to 

meet full useful life standards. If they experience fuel sulfur levels above what was considered 

when they were originally designed, they would likely no longer meet applicable Tier 3 

standards. In fact, due to the risk of Tier 3 vehicles encountering higher sulfur level fuels 

particularly during the transition of in-use fuel to 10 ppm average, we have implemented a 

provision to allow manufacturers to perform a sulfur cleanout procedure for in-use testing similar 

to the temporary Tier 2 cleanout provision. 

API, AFPM and MPC commented that “EPA indicates that a number of 2009 MY Tier 2 

vehicles easily meet the 2025 NMOG+NOx target of 30 mg/mi even when running on current 

cert fuel (15-80 ppm sulfur).” Detailed comments from API and AFPM mention that 7 of 81 

vehicles in EPA Tier Sulfur Test Program met the Tier 3 Bin 30 mg/mi standard on higher sulfur 

gasoline. Tier 3 Bin 30 emissions of 30 mg/mi NMOG+NOx represent full useful life emissions 

at 150,000 miles. Upon reviewing data from the test program, EPA identified 6 individual 

vehicles (not 7) with NMOG+NOx test results below 30 mg/mi. The test results were from only 

2 vehicle families – 2007 Honda Odyssey and 2008 Ford Focus. Emissions results of the 

vehicles tested from these two vehicle families are summarized in the table below:

Make Model

Model 

Year Vehicle ID

Accumulated 

Mileage

Average 

NMOG + 

NOx

(mg/mi)

NMOG+ 

NOx 

95% CI

(mg/mi)*

Tier 2

Certification

Bin

Tier 2 

NMOG

Standard @

120,000 

miles

Tier 2 NOx 

Standard @ 

120,000 

miles

Equivalent 

FTP 

NMOG+NOx 

@ 120,000 

miles

Honda Odyssey 2007

M503ASD0122S 35,553 32 ±3 4 70 40 110

Honda Odyssey 2007

M503ASD0187S 37,693 33 ±13 4 70 40 110

Honda Odyssey 2007

M503ASD0194L 35,742 37 ±7 4 70 40 110

Honda Odyssey 2007

M503ASD0122S 34,149 32 ±5 4 70 40 110

Honda Odyssey 2007

M503ASD0255S 36,434 28 ±3 4 70 40 110

Ford Focus 2008

N513ASD0174S 24,864 18 ±8 3 55 30 85

Ford Focus 2008

N513ASD0035L/M 35,067 21 ±17 3 55 30 85

Ford Focus 2008

N513ASD0089S 21,607 18 ±11 3 55 30 85

Ford Focus 2008

N513ASD0178L/M 27,737 15 ±4 3 55 30 85

Ford Focus 2008

N513ASD0221S 24,917 20 ±6 3 55 30 85

*95 % confidence interval based upon a 2-sided student’s t-test.

Note that none of the tested vehicles within these two vehicle families approach the 

120,000 mile or 150,000 mile full useful life of the of the Tier 3 Bin 30 exhaust emissions 

standards or the 120,000 mile full useful life of the Tier 2 emissions standards to which these 

vehicles were certified. The accumulated mileages represent approximately 18-32% of a
Tier 3 Summary and Analysis of Comments

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120,000 mile full useful life or approximately 15-25% of a 150,000 mile full useful life and thus 

none of the vehicles tested “easily meet the 2025 NMOG+NOx target of 30 mg/mi” unless the 

full useful life mileage requirements of either the Tier 3 or the previous Tier 2 standards are 

completely ignored. The comments appear to infer that emissions degradation that occurs over 

the last two-thirds to three-fourths of a vehicle’s life should be ignored or are negligible. The 

comments also imply that the approximately 50% Tier 2 compliance margins previously used by 

auto manufacturers to ensure emissions compliance that take into consideration production 

variations among vehicles and compliance with IUVP can be ignored within an analysis of 

whether a particular vehicle is reasonably expected to comply with the Tier 2 Bin 30 exhaust 

emissions standards. 

While exhaust emissions testing at accumulated mileages between 20,000 miles and 

38,000 miles are often useful for comparing emissions differences due to fuel changes or 

changes in emission control hardware, emissions at such relatively low mileage are not 

representative of the full useful life exhaust emissions to which these vehicles are certified. 

Of the five 2007 Honda Odyssey vehicles tested, only one vehicle had average 

NMOG+NOx emissions lower than 30 mg/mi (28 ± 3 mg/mi). The remaining vehicles had 

average NMOG+NOx emissions above 30 mg/mi. Even if this individual vehicle could 

demonstrate NMOG+NOx exhaust emissions at this level at 150,000 miles instead of 36,434 

miles, there would still be insufficient compliance margin for a manufacturer to demonstrate 

compliance with the standard. All of the other four, nearly identical 2007 Honda Odysseys 

tested had average NMOG+NOx emissions over 30 mg/mi even with limited mileage 

accumulation (approximately 34,000 to 38,000 miles). This family of vehicles was originally 

certified to Tier 2 Bin 4 emissions of 70 mg/mi NMOG and 40 mg/mi NOx (combined 

equivalent NMOG+NOx of 110 mg/mi) at a full useful life of 120,000 miles. The average 

NMOG+NOx emissions of 28 to 37 mg/mi for these vehicles compared with the level of the 

standards to which they are certified does not represent over-compliance with the Tier 2 Bin 4 

emissions standards to which this vehicle family was certified. The test results represent typical 

emissions for Tier 2 Bin 4 vehicles of this type when considering the vehicles’ relatively lowmileage and the Tier 2 full useful life exhaust emissions standards to which they were originally 

certified. Emissions at relatively low mileage are not representative of full useful life exhaust 

emissions because they do not account for the deterioration of exhaust catalysts and other 

emission control systems as the vehicle continues to accumulate mileage up to the regulatory full 

useful life. Even if the emissions results were from tests closer the end of useful life, emissions 

at approximately 30 mg/mi do not represent exhaust emissions consistent with a vehicle 

complying with Bin 30 since there would be insufficient compliance margin for the manufacturer 

to ensure in-use compliance with Tier 3 exhaust emissions standards even assuming a smaller 

20-40% compliance margin. 

Of the five 2008 Ford Focus vehicles tested, all five vehicles had average emissions that 

were below 30 mg/mi, although the result was not statistically different from 30 mg/mi at a 95% 

confidence level for one of the vehicles (N513ASD-0035L/M). Vehicle mileage ranged from 

just over 21,000 miles to just over 35,000 miles. This family of vehicles was originally certified 

to Tier 2 Bin 3 emissions of 55 mg/mi NMOG and 30 mg/mi NOx (combined equivalent 

NMOG+NOx of 85 mg/mi) at a full useful life of 120,000 miles. The test results represent 
Chapter 4: Proposed Vehicle Emissions Program

4-94

reasonably typical emissions for Tier 2 Bin 3 vehicles of this type when considering the vehicles’

relatively low-mileage and the Tier 2 full useful life exhaust emissions standards to which they 

are certified. As with the Honda Odyssey emissions results, the average NMOG+NOx emissions 

reported for the 2008 Ford Focus are not representative of exhaust emissions that would need to 

be achieved in order for a manufacturer to comply with Tier 3 Bin 30 full useful life exhaust 

emissions standards.

API and AFPM also cited emissions data from six additional Tier 2 vehicles tested by 

SGS to further assert that current vehicles could comply with the Tier 3 standards even when 

using Tier 2 fuels.13 EPA does not believe the data to be representative of the full-useful-life 

emissions of future Tier 3 vehicles for the following reasons:

1. The vehicles selected for testing by SGS were not representative of the broad range of 

vehicles that will need to comply with Tier 3. All of the vehicles chosen were mid-size 

or compact automobiles with 4-cylinder engines and no attempt was made to choose 

high-volume vehicles or to sales-weight the selection of vehicles. No light trucks were 

tested even though light-trucks represent more than 50% of vehicle sales.

2. The rapid thermal aging cycle used to simulate mileage accumulation and the parameters 

selected for the aging cycle appear to have been arbitrarily chosen and did not achieve 

exhaust catalyst aging conditions that would allow emissions testing representative of 

full-useful-life emissions for the tested vehicles. 

All of the vehicles tested were relatively low-mileage, with accumulated mileage of 

between 5,000 miles and 11,000. SGS relied upon rapid thermal aging of exhaust system 

components using the RAT-A cycle for 225 hours with a catalyst inlet temperature of 825 +/- 20 

°C for all vehicles to achieve conditions that they indicated would represent full-useful-life 

emissions. Catalyst aging by SGS was not conducted using the EPA Standard Bench Cycle 

(SBC) catalyst durability procedure (Title 40 CFR § 86.1823–08 "Durability demonstration 

procedures for exhaust emissions") or using an alternative, demonstrated equivalent catalyst 

aging procedure. The single catalyst inlet aging temperature selected for all of the vehicles’

exhaust systems does not appear to be representative of an aging temperature that would be 

representative for these vehicles during operation over the EPA Standard Road Cycle as required 

by 40 CFR § 86.1823–08. The vehicles tested by SGS ranged from a PFI 1.8L 140 bhp 

naturally-aspirated vehicle to a midsize, turbocharged, GDI 2.4L 200 bhp vehicle. It would be 

extremely unlikely that a single, identical catalyst-inlet aging temperature and identical 

cumulative aging time would be appropriate for rapid thermal aging across all six vehicle models 

or that such aging would also achieve the same equivalent cumulative mileage for all six 

vehicles. Data shown in figure 18 of the SGS report clearly showed remarkably different closedcoupled catalyst bed temperatures between the vehicles tested by SGS, further indicating that a 

single bench-aging temperature was very likely not appropriate for all of the vehicles. It is 

impossible to determine how the 225-hour cumulative aging time was arrived at or how it was 

 

13 Vertin, K., Reek, A. “Reversibility of Gasoline Sulfur Effects on Exhaust Emissions From Late Model Vehicles.” 

API Contract No. 2012-106409, June 20, 2013. 
Tier 3 Summary and Analysis of Comments

4-95

determined to be equivalent to 120,000 to 150,000 miles for all of the vehicles tested since the 

cumulative hours do not appear to have been determined using the Bench Aging Time equation 

from 40 CFR § 86.1823–08 and the rationale behind the choice of aging parameters was not 

reported by SGS. SGS stated in their report to API that "Manufacturers have developed 

proprietary catalyst aging tests based on RAT-A to correlate the test results with real-world 

experience. For this study, it was not feasible to use proprietary aging cycles for each of the 

vehicle systems." This statement by SGS did not demonstrate a full understanding of currently 

acceptable rapid thermal catalyst aging procedures. Manufacturers can only use proprietary 

catalyst aging cycles for which they have demonstrated equivalence to the standardized EPA 

SBC procedures (see 40 CFR 86.1823–08). It would have been entirely feasible for SGS to 

simply use the EPA SBC procedures with vehicle-specific aging times and temperatures to 

achieve an equivalent of 150,000 miles of driving and thus it is not clear why the RAT-A 

procedure was chosen for catalyst aging or if the cycle, cycle times and catalyst inlet 

temperatures were at all appropriate for aging exhaust system hardware to near full useful life 

equivalent mileage for each of the vehicles tested.

Moreover, as the comments show, the vast number of vehicles in the EPA test program 

did not meet the Tier 3 standards. As EPA discusses elsewhere, the required reductions are of a 

magnitude that for the standards to be met across the regulated fleet, EPA expects manufacturers 

to employ advances in technology in all of the relevant areas of emissions control – reducing 

engine-out emissions, reducing the time to reach catalyst light-off temperatures, improving 

exhaust catalyst durability at 120,000 or 150,000 miles and improving efficiency of fully 

warmed up exhaust catalysts. All of these areas of emissions control need to be improved, and 

gasoline sulfur reduction to a 10 ppm average is a critical part of achieving Tier 3 levels through 

these emissions control technology improvements. The use of 10 ppm average sulfur fuel is an 

essential part of achieving Tier 3 levels while applying an array of advancements in emissions 

control technology to the regulated fleet. The testing of Tier 2 and Tier 3 type technology 

vehicles, as well as other information, shows that sulfur has a very large impact on the 

effectiveness of the control technologies expected to be used in Tier 3 vehicles. Without the 

reduction in sulfur to a 10 ppm average, the major technology improvements projected under 

Tier 3 would only result in a limited portion of the emissions reductions needed to achieve Tier 3 

levels. 

Gasoline Sulfur and PM Emissions

What Commenters Said:

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

For this proposal, the Agency makes numerous inaccurate assumptions and data interpolations 

that are well outside the scope of those earlier studies. Furthermore, EPA makes several 

assertions without supporting data. For example, EPA offers no test data that compares PM 

emissions from 10 ppm and 30 ppm sulfur fuels and instead just relies on light-duty vehicle 
Chapter 4: Proposed Vehicle Emissions Program

4-96

emissions measurements on a 7 ppm sulfur test fuel to support an assertion that the proposed PM 

standards are feasible. Detailed analysis and critique of the scientific shortcoming in EPA’s 

analysis are provided in our specific comments. 

EPA offers no test data that compares PM emissions from 10 ppm and 30 ppm sulfur fuels and 

instead just relies on light-duty vehicle emissions measurements on a 7 ppm sulfur test fuel to 

support an assertion that the proposed PM standards are feasible. 

We see no justification for EPA’s comment that “FTP PM emissions increased with CO2 

emissions for the PFI vehicles”. 

When reviewing PM feasibility, EPA notes “Sulfur and nitrogen compounds are emitted 

primarily as gaseous species (SO2, NO and NO2). Sulfate compounds can be a significant 

contributor to PM emissions from stratified lean-burn gasoline engines and diesel engines, 

particularly under conditions where PGM-containing exhaust catalysts used for control of 

gaseous and PM emissions oxidize a large fraction of the SO2 emissions to sulfate (primarily 

sulfuric acid). Sulfate compounds do not significantly contribute to PM emissions from sparkignition engines operated at near stoichiometric air-fuel ratios due to insufficient availability of 

oxygen in the exhaust for oxidation of SO2 over PGM catalysts.” Given that we see little 

penetration of stratified lean-burn gasoline engines and diesel fuel sulfur is not under discussion 

for this Tier 3 rulemaking, it is not surprising that EPA offers no test data in the PM feasibility 

section comparing PM emissions from 10 ppm and 30 ppm sulfur fuels and instead just rely on 

data from a 7 ppm sulfur test fuel to support emissions compliance. 

Marathon Petroleum Company LP (MPC)

EPA offers no test data in the PM feasibility section comparing PM emissions from 10 ppm and 

30 ppm sulfur fuels and instead just rely on data from a 7 ppm sulfur test fuel to support 

emissions compliance.

EPA indicate that sulfate compounds can be a significant contributor to PM emissions from 

stratified lean-burn gasoline engines and diesel engines but does not support this with any data. 

We see no justification for EPA’s comment that “FTP PM emissions increased with CO2 

emissions for the PFI vehicles”.

Our Response:

The purpose of the PM test program on Tier 2 light-duty vehicles was to demonstrate the 

feasibility of Tier 3 PM emission standards using Tier 2 vehicles at full useful life. The purpose 

was not to investigate the effect of fuel sulfur level on Tier 2 light-duty PM emissions. Sulfate 

emissions were measured from the Tier 2 light-duty study. The largest sulfate emissions 

measured in the study were 0.13 mg/mile on the FTP cycle, and 0.32 mg/mile on the US06 cycle. 

The average sulfate emissions across vehicles were only .021 mg/mile on the FTP cycle, and 

0.077 mg/mile on the US06 cycle. 
Tier 3 Summary and Analysis of Comments

4-97

Measurements from the Kansas City Light-Duty Vehicle Emissions Study tested in-use 

light-duty gasoline vehicles with much higher fuel sulfur content, and found that the sulfate 

contribution to the PM emissions was still relatively minor for light-duty gasoline vehicles. The 

sulfate emissions constituted less than 1% of PM start emissions, and less than 10% of running 

emissions14. As such, even if the fuel sulfur content was increased to 30 ppm in the Tier 2 lightduty PM emission study, the increase in PM emissions is expected to be relatively minor, and 

would not impact the demonstration of feasibility of achieving the proposed Tier 3 PM 

standards. 

The comment from API regarding FTP PM emissions in relation to CO2 emissions from 

PFI vehicles originated from text describing a preliminary graph of the results from the test 

program. The text in question does not accurately describe the data. However, the text was only 

observational in nature, and was inconsequential relative to the purpose of the associated 

Figures, which was to show the technological feasibility of the proposed PM standards. In 

response, we have removed the text in question regarding a CO2/PM relationship from the 

figures in the final RIA.

Regarding Marathon’s comment of there being no supporting data to indicate that sulfate 

compounds can be a significant contributor to PM emissions from stratified lean-burn gasoline 

engines and diesel engines, it should be very clear that all lean NOx catalytic reduction systems 

with sufficient activity to meet Tier 3 with either lean-burn gasoline or diesel vehicles (e.g., 

compact urea SCR systems, NOx adsorption catalysts and variations/combinations of these 

systems) all rely heavily on Pt/Pd oxidation catalysts as key system components. As a petroleum 

refiner, Marathon should be well aware of the oxidation reactions that form sulfate from SO2 

over Pt/Pd catalysts under net oxidizing conditions. These reactions and subsequent hydration 

and formation of sulfate particulate are concisely summarized within the text by Heck et al. and 

also by numerous other sources.15

Evaluation of Emissions at Gasoline Sulfur Levels of 10 ppm and 30 ppm 

What Commenters Said:

Marathon Petroleum Company LP (MPC)

EPA utilized very few studies none of which looked at sulfur effects over the range of 10 to 30 

ppm.

 

14 Sonntag, D. B., R. W. Baldauf, C. A. Yanca, C. R. Fulper C. R. Particulate Matter Speciation 

Profiles for Light-Duty Gasoline Vehicles in the United States. J. Air & Waste Manag. Assoc. 

Published online December 13, 2013. DOI: 10.1080/10962247.2013.870096.

15 Heck, R.M., Farrauto, R.J., Gulati, S.T. Equation # 8.2 and surrounding text. “Catalytic Air Pollution Control –

Commercial Technology, 2nd Edition.” John Wiley and Sons, Inc., 2002.
Chapter 4: Proposed Vehicle Emissions Program

4-98

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

EPA relies on very few studies to support its proposal to lower the average annual sulfur 

standard for gasoline below the current level of 30 ppm. None of these studies evaluate vehicle 

emission control system response to changes in gasoline sulfur content either between or within 

the range defined by the proposed level of 10 ppm S and the current standard (30 ppm S). As 

such, EPA can only conjecture on what is necessary to meet the proposed Tier 3 emissions 

standards. 

In developing the 10 ppm gasoline sulfur average, EPA relied on very few studies to support 

their position, none of which look at the linearity of sulfur effects between 10 and 30 ppm to 

understand vehicle emission system response over the range of interest. 

EPA proceeds to provide additional support for the “insight” into the fuel sulfur impacts on “Tier 

3 like” vehicles by reviewing the data from the “Umicore” study (a single PZEV vehicle) which 

we’ve already discussed above. Thus it would appear that EPA lacks data on Tier 3 emission 

level vehicles at the sulfur levels of interest, namely between 10 ppm and 30 ppm, to fully 

understand and comment on the appropriate and necessary fuel sulfur levels to allow compliance 

with the Tier 3 emissions requirements. Proceeding to a formal decision without providing the 

underlying supporting data prevents informed public comment, is a departure from accepted 

scientific rigor and ultimately is a violation of the Administrative Procedures Act.

Even after all the above data have been discussed, EPA indicated in Chapter 1.2.3.4 of the DRIA 

that “A gasoline sulfur standard of 10 ppm also represents the highest level of gasoline fuel 

sulfur that will allow compliance with a national fleet average of 30 mg/mi NMOG+NOx.” 

Nowhere has EPA even tested levels above 10 ppm sulfur other than the Tier 2 baseline 

comparison at the current average sulfur level of 30 ppm. This is a serious deficiency in the 

overall technical justification for the 10 ppm sulfur level. 

Pennsylvania Department of Environmental Protection (DEP )

Neither the proposed rule nor the regulatory impact analysis adequately explains how emission 

reductions were estimated. The proposed rule mentions that studies were performed that 

examined emission reductions occurring in vehicles when 3 ppm, 5 ppm, and 6 ppm sulfur 

gasoline are used, but not 10 ppm sulfur gasoline. How did the EPA determine what reductions 

would occur at 10 ppm sulfur? Regarding catalytic converter operation, the proposed rule states 

that reactions ‘ ... can be blocked by sulfur blinding and may be responsible for observation of 

reduced NOx activity over [palladium] Pd/ceria catalysts even with exposure to fairly low levels 

of sulfur (equivalent to 15 ppm in gasoline)’ (78 FR 29864). EPA also indicates that Pd catalysts 

will be important to meeting Tier 3 standards. Emissions in vehicles at 6 ppm sulfur gasoline are 

low according to the studies mentioned, but at 15 ppm sulfur reactions that reduce NOx are 

blocked, which indicates that the catalysts’ efficiency may be responding non-linearly to sulfur 

levels in gasoline. Did EPA consider that catalyst operation may not be nearly as efficient at 10 

ppm sulfur in gasoline as it is at 3 ppm, 5 ppm, or 6 ppm? DEP cannot discern from the 
Tier 3 Summary and Analysis of Comments

4-99

explanations given in the proposed rule how the control efficiency of the catalyst using 10 ppm 

sulfur gasoline was derived. This is very important because the monetized health benefits are 

directly calculated using the estimated emissions reductions. 

Our Response:

There have been a number of published studies of the effects of gasoline sulfur levels on 

NMOG and NOx emissions, particularly those for Tier 2/LEV II and cleaner emission control 

technologies. Although limited, most of the cited studies included testing of fuel sulfur levels 

that cross the range of 10 ppm to 30 ppm fuel sulfur and thus provide important insight into the 

emissions impacts of reducing gasoline sulfur levels from a national average of 30 ppm sulfur 

under Tier 2 to an average of 10 ppm sulfur under Tier 3 (Takei et al, 2000; Ball et al., 2011; 

EPA 420-R-07-002, 2007; EPA 420-R-13-002, 2013). At the time of the NPRM, these were the 

most recently available studies on effects of gasoline sulfur on exhaust emissions. After the 

NPRM, EPA reviewed additional, supplemental studies and data submissions and cites this 

information within Preamble IV.A.6 of the Tier 3 final rule. This includes a contract report from 

SGS Environmental testing submitted by API as part of its Tier 3 comments (Vertin and Reek, 

2013), an updated, peer-reviewed EPA report on emissions impacts of gasoline sulfur on highsales-volume Tier 2 vehicles (EPA 420-R-14-002, 2014), data from EPA’s repeat testing of the 

previously tested (Ball et al., 2011) PZEV Chevrolet Malibu, data from EPA’s developmental 

Tier 3 Bin 30 Chevrolet Silverado testing and supplemental data submitted by Ford Motor 

Company on a Tier 3 Bin 50 Ford Explorer. This data is summarized within the RIA and 

Preamble IV.A.6. All of the data was analyzed to characterize emissions changes when reducing 

average gasoline sulfur from 30 ppm S to 10 ppm S. Most of the additional data generated by 

EPA or submitted to EPA by industry focused on emissions from low-emitting Tier 2 (bins 3 and 

lower) or developmental prototype Tier 3 vehicles.

EPA has drawn from all of the analyses identified above to determine that the 

relationship between changes in gasoline sulfur content and NOx, HC, NMHC and NMOG 

emissions is typically linear. The linearity of sulfur impacts on NOx, NMHC and NMOG 

emissions is supported by past studies with multiple fuel sulfur levels all of which compare 

gasoline with differing sulfur levels that are below approximately 100 ppm (e.g., CRC E-60 and 

2001 AAM/AIAM programs as well as comments submitted to this rulemaking by MECA cited 

within Preamble IV.A.6). As stated within Preamble IV.A.6, the relative linearity of the effect of 

gasoline sulfur level on NMOG and NOx emissions allows exhaust emissions results generated 

within EPA and other studies of gasoline sulfur at levels immediately above or below either 10 

ppm or 30 ppm to be normalized to either 10 ppm sulfur or to 30 ppm sulfur. This allowed EPA 

to evaluate vehicle emission control system response to changes in gasoline sulfur content 

adjacent to or within the range defined by the Tier 3 Standard of 10 ppm S and the current 

standard (30 ppm S) for the data cited within Preamble IV.A.6 and the RIA.

EPA Citation of Toyota Technical Paper on Fuel Property Requirements for Advanced 

Technology Engines

What Commenters Said:
Chapter 4: Proposed Vehicle Emissions Program

4-100

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

To provide additional support for the proposed change in fuel sulfur levels, EPA comments on 

the impact of sulfur on “Tier 3 like” vehicles. In the first instance, EPA indicates that “Emissions 

of vehicles certified to the SULEV standard of the California LEV II program, or the equivalent 

Tier 2 Bin 2 standards, can provide some insight into the impact of fuel sulfur on vehicles at the 

very low proposed Tier 3 emissions levels. Vehicle testing by Toyota of LEV I, LEV II, ULEV 

and prototype SULEV vehicles showed larger percentage increases in NOx and HC emissions 

for SULEV vehicles as gasoline sulfur increased from 8 ppm to 30 ppm, as compared to other 

LEV vehicles they tested.” EPA does not include a reference for this work nor does it appear at 

first glance to be in the docket (searching the 600+ docket titles for Toyota). Given the lack of 

reference and supporting information, we cannot evaluate, provide informed comment, nor 

accept the Toyota program outcomes mentioned to support fuel sulfur effects on proposed Tier 3 

emission level vehicles. 

EPA references test data from Toyota to support their position but do not provide any details or 

the reference material.

Marathon Petroleum Company LP (MPC)

EPA references test data from Toyota to support their position but do not provide any details or 

the reference material.

Manufacturers of Emission Controls Association (MECA)

The negative impacts of gasoline fuel sulfur content on catalytic emission controls are 

highlighted in a newly revised MECA report: “The Impact of Gasoline Fuel Sulfur on Catalytic 

Emission Control Systems” (available on MECA’s public website, www.meca.org, under 

Resources >> Reports). This MECA gasoline fuel sulfur report includes the Toyota 2000 SAE 

paper reference that showed strong sulfur sensitivity on the emissions performance of a 

prototype SULEV vehicle that employed a close-coupled three-way catalyst and an underfloor 

converter that utilized a combination three-way catalyst plus hydrocarbon adsorber design. In 

their published test results both hydrocarbon and NOx FTP emissions increased significantly 

when the gasoline fuel sulfur level was increased from 8 ppm to 33 ppm (additional large 

increases in hydrocarbon and Nox FTP emissions were observed when the fuel sulfur level was 

increased to 150 ppm). The reference for this Toyota paper is SAE paper number 2000-01-2019. 

API and AFPM note in their comments that EPA neglected to include a reference for this work 

in their Tier 3 proposal.

Our Response:
Tier 3 Summary and Analysis of Comments

4-101

The specific citations were included within the Preamble to the Proposed Rule, 

specifically, preamble citation footnote numbers 229 and 230

16

: 

229 Takei, Y., Kungasa, Y., Okada, M., Tanaka, T. Fujimoto, Y. (2000). Fuel Property 

Requirement for Advanced Technology Engines. SAE Technical Paper 2000–01–2019.

230 Takei, Y., Kungasa, Y., Okada, M., Tanaka, T. Fujimoto, Y. (2001). ‘‘Fuel 

Properties for advanced engines.’’ Automotive Engineering International 109 12, 117–

120.

A search containing search terms for the primary author, “Takei”, would also have yielded the 

specific citations in question.

Gasoline Sulfur and Lean-burn Gasoline Spark-ignition Engines 

What Commenters Said:

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

EPA asserts that sulfate compounds can be a significant contributor to PM emissions from 

stratified lean-burn gasoline engines and diesel engines with no supporting data on technology 

deployment(s) . .

Lean burn gasoline direct injection (GDI) engine technology is specifically identified in the auto 

industry white paper referenced by EPA in the NPRM as demonstrating the need for 10 ppm 

sulfur in the United States. However, as we have noted in previous comments on the white paper 

(included as Attachment No. 3), the penetration of this technology into the market place in areas 

such as Japan and Europe (where gasoline sulfur is capped by regulation at 10 ppm) has been 

limited and is not expected to grow. Instead, it is expected that the automakers will rely on other, 

more cost-effective technologies which will not require the highly sulfur sensitive and costly 

exhaust aftertreatment devices needed with lean-burn engines. In the US, it is expected that the 

maximum potential share for lean-burn engines will reach ~3% between 2015 and 2020 and 

decline thereafter as observed in Japan and Europe, according to research by The Martec Group 

(Executive Summary is provided as Attachment No . 8). 

This issue was addressed at length in Section I.A. EPA boldly asserts that reducing gasoline 

sulfur levels to 10 ppm will enable newer technologies that could improve fuel economy. 78 

Federal Register 29820. EPA claims this benefit in a single sentence in the proposed rule 

concerning lean-burn engines without any rationale or justification whatsoever. Similarly, the 

draft RIA contains exactly one sentence regarding lean-burn engines with no supporting data or 

evidence. DRIA at 1-31. This cannot be taken seriously as a justification for the proposed 

reduction of sulfur to 10 ppm. If EPA does seriously intend for this to be a justification for the 

rule, EPA should re-issue the proposal providing its rationale and data for such an assertion so 

 

16 U.S. Federal Register, Vol. 78, No. 98, Tuesday, May 21, 2013, Proposed Rules, footnotes at the bottom of page 

29862.
Chapter 4: Proposed Vehicle Emissions Program

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that it can be properly evaluated and commented upon by the public, as required by section 

307(d) of the Clean Air Act. 

In any event, there is no basis to claim that lean-burn technology is likely to expand in the U.S. 

and that lowering gasoline sulfur will enable such expansion. In other regions of the world where 

such technology has been introduced, the automobile manufacturers have indeed been scaling 

back its use, not expanding its use. 

The American Petroleum Institute (API) recently became aware that the Manufacturers of 

Emission Controls Association (MECA) submitted “supplemental” comments to the EPA Tier 3 

Rulemaking Docket that were critical of comments which we had filed jointly with the American 

Fuel and Petrochemical Manufacturers (AFPM) on June 28, 2013 concerning the Tier 3 Notice 

of Proposed Rulemaking (NPRM). Specifically, MECA stated that the intent of its submittal 

was:

“...to provide additional information and comments on four important topics: 1) the importance 

of 10 ppm average sulfur gasoline to meeting proposed Tier 3 emission limits; 2) the synergy 

between ultra-low sulfur gasoline and the introduction of cost effective, lean-burn, gasoline 

direct injection technology with improved fuel consumption; 3) costs associated with Tier 3 

compliance on gasoline light-duty vehicles; and 4) harmonization with ARB’s 1 mg/mile LEV 

III PM standard.”

In this submittal, MECA attempts to rebut the API/AFPM written comments concerning: (a) 

EPA’s inadequate justification of a technical need for a 10 ppm gasoline S standard, and (b) the 

future market penetration prospects for lean-burn GDI technology in the US light-duty vehicle 

fleet. 

The supplemental comments from MECA are based upon very limited data that have not been 

independently validated and that were generated using test fuels with potentially confounded 

properties. In addition, MECA’s outlook for lean-burn GDI technology in the US ignores the 

real-world experience of this technology in the European and Japanese markets where 10 ppm 

gasoline sulfur regulations have been in place. Our detailed response regarding each of these 

topics is further elucidated below.

MECA asserts that lean NOx adsorber catalysts are the preferred strategy for reducing NOx on 

lean GDI light-duty engines and claims that 10 ppm sulfur gasoline is necessary for the use of 

this technology in the U.S. However, MECA does not explain why lean-burn GDI technology 

failed to enter the European and Japanese markets in significant volumes after these two regions 

adopted 10 ppm gasoline sulfur standards. (i.e., market penetration of lean-burn GDI peaked at 

~2% and has since been declining.) MECA also alludes to two European OEMs who want to 

introduce this technology into the US market. Given the relatively low US gasoline light-duty 

vehicle market penetration by European OEMs, combined with the relatively high incremental 

cost of this technology, MECA’s comments do not contradict an analysis performed by the 

Martec Group which estimates that the market opportunity for lean-burn GDI is limited to at 

most ~3% by 2020.
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We further note that the Agency agreed with Martec’s evaluation of lean-burn GDI technology in 

its regulatory impact assessment conducted for the final rulemaking, “2017 and Later Model 

Year Light-Duty Vehicle Greenhouse Gas Emissions and Corporate Average Fuel Economy 

Standards.” Specifically, the EPA did not use lean-burn GDI in the vehicle technology packages 

that were evaluated for that rulemaking as it was found less cost effective than other available 

technologies. In short, the Agency agreed with API’s comments on this issue.

Marathon Petroleum Company LP (MPC)

In any event, there is no basis to claim that lean-burn technology is likely to expand in the U.S. 

and that lowering gasoline sulfur will enable such expansion. In other regions of the world where 

such technology has been introduced, the automobile manufacturers have indeed been scaling 

back its use, not expanding its use. 

Manufacturers of Emission Controls Association (MECA)

API and AFPM in their Tier 3 comments are also negative concerning the future application of 

lean burn, gasoline direct injection engine technology in the U.S. to comply with future EPA 

greenhouse gas/fuel economy standards. Their comments indicate that the market share for leanburn engines in the U.S. will reach only about 3% between 2015 and 2020 and decline thereafter 

(based on research done by The Martec Group). The auto industry has generally expressed 

significant interest in lean GDI engines in comments made at both Tier 3 public hearings held in 

Philadelphia and Chicago in April 2013. This auto industry interest is specific to the potential for 

lean GDI engines to deliver up to 20% improvements in fuel consumption relative to 

stoichiometric GDI engines (which in turn have lower fuel consumption than port fuel injection 

gasoline engines). A recent analysis of EPA’s estimates of costs to meet their future light-duty 

2017-2025 greenhouse gas emission standards by Dr. Timothy Johnson of Corning, Inc. (see 

SAE Int. J. Engines 6(2):2013, doi:10.4271/2013-01-0538) indicates that CO2 reductions will 

cost about $100/% CO2 reduced in the 2020-2025 timeframe. According to recent Ricardo 

estimates, lean GDI engine technology can deliver about 20% lower fuel consumption at a cost 

of about $30/% CO2 reduced. This relatively attractive cost for reducing CO2 emissions relative 

to EPA’s estimates for costs to reduce CO2 emissions in the 2020-2025 timeframe should drive 

auto industry interest and adoption of lean GDI engines to meet future U.S. greenhouse gas 

standards. 

As MECA and the auto industry have both pointed out in public comments, a 10 ppm sulfur 

average gasoline standard is an important enabler for allowing lean GDI engines to meet 

proposed Tier 3 emission limits and deliver cost effective CO2 reductions. In our previous Tier 3 

comments, MECA noted that lean NOx adsorber catalysts are the preferred strategy for reducing 

NOx on lean GDI light-duty engines and NOx adsorber catalysts have known strong sensitivities 

to gasoline fuel sulfur levels (see for example Toyota’s SAE paper number 2000-01-2019 

referred to previously). At least two European auto manufacturers offer lean GDI vehicles that 

utilize lean NOx adsorber catalysts for NOx control in Europe and the current gasoline sulfur 

levels present in the U.S. market prevent these manufacturers from offering these lean GDI 

vehicles in the U.S. market. Emission control manufacturers are working with their automotive 
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customers to make lean NOx adsorber catalysts more effective and less costly (as shown in the 

recent SAE paper number 2013-01-1299, referenced in MECA’s earlier Tier 3 comments), but 

lower sulfur gasoline is necessary to make lean GDI a viable future option in the U.S. market. 

Without 10 ppm sulfur gasoline, manufacturers will be forced to use more costly approaches for 

reducing CO2 emissions from future light-duty vehicles.

In addition to the need for a 10 ppm national average sulfur limit on gasoline for compliance 

with EPA’s proposed Tier 3 emission standards, the availability of ultra-low sulfur gasoline will 

also open up opportunities for vehicle manufacturers to develop and commercialize lean gasoline 

engines that can provide improved fuel economy benefits relative to stoichiometric gasoline 

engines. A number of manufacturers are offering lean gasoline engine options in Europe and are 

interested in using this lean combustion approach to meet more stringent, future U.S. fuel 

economy/greenhouse gas emission standards. Lean gasoline engines will require the use of a lean 

NOx emission control technology to comply with proposed Tier 3 emission standards. Lean NOx 

adsorber catalysts are being used in Europe (where the gasoline sulfur cap is 10 ppm) on lean 

gasoline engines to reduce NOx emissions from these lean engines. Lean NOx adsorber catalyst 

performance is significantly impacted by gasoline fuel sulfur levels – the NOx adsorber function 

of these catalysts also strongly adsorb sulfur constituents present in the exhaust. Ultra-low sulfur 

gasoline is an important enabler for maximizing the performance of lean NOx adsorber catalysts, 

minimizing the duration and frequency of NOx adsorber desulfation events, and maximizing the 

potential fuel economy benefits of lean engine operation. A recent SAE publication (SAE paper 

no. 2013-01-1299) describes recent efforts to optimize the performance and desulfation 

characteristics of lean NOx adsorber catalysts that are targeted for a light-duty lean gasoline 

engine application. A national 10 ppm gasoline sulfur average requirement will provide 

manufacturers with the opportunity to use lean gasoline engine technology as an option for 

meeting future U.S. fuel efficiency/greenhouse gas standards. 

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

OEMs need a low sulfur content of fuel in order to introduce advanced lean burn gasoline direct 

injection (GDI LB) engines that will enable better fuel system efficiency. LB engine technology 

requires the use of highly efficient Lean NOx Absorbers or Traps (LNT) because of the 

technology’s inherent higher “engine out” NOx rates. The LNT is more sensitive to gasoline 

sulfur poisoning than conventional automotive three way catalysts because of its specific catalyst 

chemistry which binds more strongly with the sulfur. As little as a few parts per million of fuel 

sulfur will start to bind to the catalyst active sites and require high temperature (~500-600 C), 

fuel enriched regeneration events to restore the LNT efficiency. If fuel sulfur is not near zero, 

then more energy is needed to regenerate the catalyst than may be conserved by the lean burn 

technology itself, jeopardizing its cost effectiveness. 

Some groups have asserted that EPA has not identified any automotive technologies that would 

benefit from lower sulfur gasoline and that will be utilized to comply with CAFE/GHG standards 

and Tier 3 standards. This assertion is false. The lower sulfur fuel will allow for improved 

technology crucial for meeting the new criteria pollutant standards. For example, the use of GDI 

technologies is referenced by EPA in the MY 2017 rule technical support document, which 
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notes: “EPA and NHTSA’s current assessment is that the availability of ultra-low sulfur (ULS 

less than 15 ppm sulfur) gasoline is a key technical requirement for lean burn GDI engines to 

meet EPA’s Tier 2 NOx emission standards”. 10 ppm sulfur will result in increased used of 

optimized GDI and similar technologies in gasoline engines, as it has done for diesel engines. 

While we recognize that despite 10 ppm sulfur cap standards, adoption levels of complete 

GDI/LB technology in Europe and Japan have been low to date, some components of the 

technologies have been widely used. The full suite of technologies has not been adopted simply 

because emission limits have been less stringent than Tier 3, and therefore not all of the pollution 

control equipment is required. Because Tier 3 will require more stringent reductions in criteria 

emissions, past GDI/LB adoption in Europe and Japan is not predictive of the developing U.S. 

response. 

Mercedes-Benz USA, LLC on behalf of Daimler AG

The 10 ppm retail average and 20 ppm refinery gate/25 ppm retail caps are necessary to optimize 

fuel efficiency and maintain the function of advanced engine and exhaust aftertreatment 

technologies. In 2006, Mercedes-Benz first capitalized on Ultra low sulfur gasoline and the 

concomitant fuel consumption that resulted when it introduced in the EU, the CLS 350CGI 

which is equipped with stratified lean burn combustion. Depending on the driving mode, engine 

speed and load, gains in fuel efficiency can range between 5-15% as compared to conventional 

stoichiometric combustion. Fuel efficiency gains and CO2 reductions of this magnitude, required 

by the GHG mandate and enabled by lean burn combustion, illustrate the importance of this 

technology and the need for universal availability of low sulfur gasoline in the US to the 

Mercedes-Benz GHG Compliance Plan. 

While it is possible to dislodge the embedded sulfur through various mechanisms which raise the 

exhaust gas temperature sufficiently to ‘burn off’ such deposits, in practice, it is far more 

difficult to burn off sulfur deposits given the nature of emerging, higher-efficiency combustion 

technologies which extract more energy from the fuel resulting in lower operating temperatures 

of exhaust devices. These ‘sulfur burn off’ events are required to maintain pollutant conversion 

efficiency of exhaust aftertreatment devices, but they come with a substantial fuel economy 

penalty. When market fuel sulfur concentrations exceed 20 ppm, fuel efficiency gains can be 

completely negated in the effort to maintain regulated emission control function. 

Lean burn combustion among those technologies necessary to accomplish a nearly 50 percent 

reduction in greenhouse gas emissions requires low sulfur gasoline for peak efficiency. Fuel 

efficiency gains in CO2 reductions of this magnitude required by the greenhouse gas mandate are 

enabled by lean burn combustion, illustrate the importance of this technology and the universal 

availability of low sulfur gasoline in the U.S. to the Daimler Greenhouse Gas Compliance Plan. 

Our Response:

There are two primary rationales for reducing gasoline sulfur to an average of 10 ppm As 

discussed in the preamble and elsewhere in this document. The first is to provide an immediate 

reduction in emissions from the existing Tier 2 fleet. The second is to enable compliance with 
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the Tier 3 Bin 30 fleet-average emissions standard, with the assumption that the majority of 

light-duty vehicles would use stoichiometric-combustion, spark-ignition gasoline engines. 

Although both the oil and the automotive industry commented on lean-burn technology and low 

sulfur gasoline, we did not rely on the broader commercialization of lean-burn engine technology 

as a potential pathway to compliance with the Tier 3 standards, and we do not address in this rule 

the impact of fuel sulfur on the performance of vehicles with this technology.

Gasoline Sulfur and GHG/Fuel Economy

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

Sulfur Reductions Facilitate More Fuel Efficient Vehicle Technology. As engine efficiency 

increases, more work is extracted from the fuel during the combustion process and less energy is 

rejected as “waste” heat to the cooling system and in the exhaust system. Certain technologies 

such as lean burn combustion and turbocharged induction, promote cooler exhaust temperatures 

as compared to naturally aspirated induction and stoichiometric combustion. Such cooler exhaust 

gas temperatures both facilitate sulfur deposition and inhibit its removal during periodic “burn 

off” cycles. These events are required to maintain conversion efficiency of exhaust after 

treatment devices and come at a substantial fuel economy penalty. In the extreme, depending on 

the sulfur level present in the fuel, fuel efficiency gains can be completely negated in the effort to 

maintain emission control function. 

Some groups have asserted that EPA has not identified any automotive technologies that would 

benefit from lower sulfur gasoline and that will be utilized to comply with CAFE/GHG standards 

and Tier 3 standards (54). This assertion is false. The lower sulfur fuel will allow for improved 

technology crucial for meeting the new criteria pollutant standards. For example, the use of GDI 

technologies is referenced by EPA in the MY 2017 rule technical support document, which 

notes: “EPA and NHTSA’s current assessment is that the availability of ultra-low sulfur (ULS 

less than 15 ppm sulfur) gasoline is a key technical requirement for lean burn GDI engines to 

meet EPA’s Tier 2 NOx emission standards”. 10 ppm sulfur will result in increased used of 

optimized GDI and similar technologies in gasoline engines, as it has done for diesel engines. 

American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

EPA has failed to demonstrate that reducing gasoline sulfur levels to 10 ppm is necessary to 

enable newer technologies that EPA claims could improve fuel economy 

Marathon Petroleum Company LP (MPC)

EPA has entirely failed to demonstrate that reducing gasoline sulfur levels to 10 ppm is 

necessary to enable newer technologies that EPA claims could improve fuel economy
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This issue was addressed at length in Section II.A. EPA boldly asserts that reducing gasoline 

sulfur levels to 10 ppm will enable newer technologies that could improve fuel economy. 78 

Federal Register 29820. EPA claims this benefit in a single sentence in the proposed rule 

concerning lean-burn engines without any rationale or justification whatsoever. Similarly, the 

draft RIA contains exactly one sentence regarding lean-burn engines with no supporting data or 

evidence. DRIA at 1-31. This cannot be taken seriously as a justification for the proposed 

reduction of sulfur to 10 ppm. If EPA does seriously intend for this to be a justification for the 

rule, EPA should re-issue the proposal providing its rationale and data for such an assertion so 

that it can be properly evaluated and commented upon by the public, as required by section 

307(d) of the Clean Air Act. 

American Honda Motor Co., Inc.

It should also be noted that the Tier 3 standards have an important relationship with other 

recently finalized vehicle regulations, the model year 2017-2025 fuel economy and vehicle 

greenhouse gas standards. As a result of the latter set of standards, numerous efforts are now 

underway to improve the thermal efficiency of advanced internal combustion engines. These 

efforts are successfully reducing waste heat, delivering more energy to the wheels. Yet because 

catalysts use wasted engine heat to reach operating temperatures, cooler engines mean lower 

catalyst operating temperatures. These catalysts are more prone to being poisoned by sulfur in 

the fuel. Countermeasures to ensure aftertreatment operability in a sulfur-rich environment 

would require burning unnecessary excess fuel, eroding mpg and putting additional greenhouse 

gas emissions into the atmosphere – exactly the opposite of the intended fuel economy and 

greenhouse gas regulations. 

Manufacturers of Emission Controls Association (MECA)

Sulfur deactivation of three-way catalysts negatively impacts the active precious metal catalysts, 

oxygen storage materials, and other activity promoters found in these sophisticated catalysts. 

The coverage and negative impacts of sulfur poisons on three-way catalysts depends in part on 

the temperature history of the catalytic converters found on the vehicle. Exhaust temperatures 

are expected to cool in the future as manufacturers reduce vehicle waste heat to meet future 

vehicle fuel efficiency and greenhouse gas standards. These cooler converter operating 

temperatures cause catalysts to accumulate higher amounts of sulfur poisons with today’s 

gasoline sulfur levels, resulting in higher emission levels of pollutants like hydrocarbons and 

NOx. 

Mercedes-Benz USA, LLC on behalf of Daimler AG

As engine efficiency increases, more work is extracted from the fuel during the combustion 

process and less energy is rejected as ‘waste’ heat in the cooling system and in the exhaust 

stream. Certain technologies especially lean burn combustion and turbocharged induction, 

promote cooler exhaust gas temperatures as compared to naturally aspirated induction and 

stoichiometric combustion. Such cooler exhaust gas temperatures facilitate sulfur deposition. 

During the combustion process, sulfur, in various compound forms, is present in the exhaust 

stream and is readily deposited on the surface of exhaust aftertreatment devices including 
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oxidation and reduction catalysts as well as NOx adsorption components. It is on these surfaces 

that precious metals are placed by design to provide the conversion sites for the chemical 

reaction which converts pollutants to harmless gases. This surface contamination with sulfur 

reduces the conversion efficiency of exhaust aftertreatment components. In fact, even low levels 

of sulfur impede the function of these devices especially if previously subjected to higher sulfur 

fuels. However, the cooler exhaust gas temperatures brought about through increased efficiency 

associated with lean burn and other advanced technologies also inhibit sulfur removal during 

periodic ‘burn off’ cycles. 

Our Response:

EPA generally agrees with the comments by Alliance, Global Automakers, MECA, and 

Mercedes-Benz regarding the reduction in exhaust temperatures of stoichiometric-combustion 

engines as part of GHG emissions compliance and disagrees with the statements by API and 

MPC, based on the analysis in preamble Section IV.A.6 and RIA Chapter 1. As described in 

preamble Section IV.A.6, EPA agrees that as engine efficiency is improved via reductions in 

pumping losses, friction and other means, the general trend will be towards lower exhaust 

temperatures that can both increase sulfur adsorption onto active catalytic surfaces and make 

removal of sulfur from those surfaces more difficult. 

Comments on GHG, CAFE, and CO2 emissions are beyond of the scope of the Tier 3 

rulemaking.

4.1.5. LD Exhaust Standards: Other Issues

4.1.5.1. Early Credits/Early Tier 3 Compliance

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

EPA has proposed a mechanism that would allow for the generation of early credits from two 

model years prior to the beginning of the Tier 3 standards. There are, however, certain aspects of 

the proposal that are unclear. Additionally, manufacturers’ efforts to earn early credits can be 

frustrated because of the differences in the bin structure between the Tier 2 program and the LEV 

III/Tier 3 programs. 

Rather than dividing the fleet between vehicles over and under 6,000 pounds GVWR, EPA could 

simply combine the < 8,500 pounds GVWR emission credits federally and compare those to the 

CA+177 State pooled emission credits (appropriately scaled to a nationwide sales). This would 

simplify the calculations. 

While the language of the preamble and proposed regulation make it clear that the cap is to be

computed based upon the ratio of nationwide (50-state) sales to California-only sales, the 

language related for the computation of the potential early credits is less clear. For the latter, it is 
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not clear whether the language was intended to indicate whether this computation should be 

based upon nationwide sales or whether it should be based upon only the sales of the “federal” 

fleet (i.e., excluding the CA+177 State fleet (i.e., 37-state sales)). EPA staff have subsequently 

verbally clarified that the intent is to base this early credit computation only upon the federal 

fleet excluding CA+177 States (or 37-state sales). This expectation should be clarified in the 

final rule, since it is needed to implement the early credits in just a few years and clarification in 

the final rule would avoid EPA being required to later issue a separate guidance document or 

technical amendment. 

Additionally, the proposal was to compute the “cap” by multiplying California credits by 50-

state sales divided by California sales. However, given that the California LEV III regulations 

allow the option (which most, if not all, manufacturers are expected to use) to base compliance 

upon the pooled CA+177 State fleets, EPA should revise the cap computation to specify CA+177 

State credits multiplied by 50-state sales divided by CA+177 State sales. 

For the possible but unlikely case that a manufacturer may not choose to use the CA+177 State 

pooling option, the EPA proposed cap based upon the ratio of 50-state to California only sales 

could work. However, for consistency it would be best to also have such manufacturers do the 

computation on a CA+177 State basis. In this case, the manufacturer could sum all of the credits 

from the separate fleets to create a CA+177 State total and then apply the ratio based upon total 

sales in the combined states. 

Allow LEV III/Tier 3 Bins in MYs 2015-2017. Due to the differences in the Tier 2 and LEV 

III/Tier 3 bin structure, some manufacturers could find it difficult to earn early credits unless 

they created unique vehicle designs and/or calibrations solely for the purposes of earning early 

credits. The result could be that they would need to sell a fleet mix that would end up having 

lower fleet average emissions than their respective California/177 State fleets. However, we 

think it should be reasonable to earn early Federal credits for selling vehicles that are cleaner 

than required under the Tier 2 program and which would already be designed and sold for 

compliance with the California program applicable to MYs 2015 and 2016. 

For example, a number of manufacturers would expect to comply with the required LEV III fleet 

averages for MYs 2015 and 2016 by selling a fleet mix containing a significant fraction of 

ULEVs (i.e., Bin 125) averaged with SULEV-PZEVs (i.e., Bin30). However, there is no Bin 125 

or equivalent bin available under the Tier 2 program. This means California ULEVs would either 

have to certify to Bin 4 or 5 under the Tier 2 program. If certified to Bin 5 (equivalent to 160 

mg/mi on an NMOG+NOx basis), they would not earn any early credit. If certified to Bin 4 

(equivalent to 110 mg/mi), the vehicles would have to be designed for lower emissions than 

required by the California program. It would be inefficient to have to design unique vehicles for 

this purpose, plus it would be challenging (and perhaps even infeasible) to do so given the short 

available lead time and the need to comply with the separate 0.04 mg/mi NOx standard 

associated with Bin 4. 

We understand, however, that EPA does not intend to reopen the Tier 2 program, but we still 

believe it is possible for EPA to provide early credits for interim Tier 3 vehicles certified in MYs 

2015-2017. The conditions for certification should be the same as available in the California 
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program (i.e., E0 and 120K useful life, although a manufacturer should not be precluded from 

using E10 or E15 and/or a useful life of 150K if they had a reason to do so) If such conditions 

are acceptable in MY 2017 there should be no reason for not allowing certification to these 

conditions prior to MY 2017. 

EPA should make all of the LEV III/Tier 3 bins below Bin 160 available for the purposes of 

earning early Federal credits as interim Tier 3 vehicles. This would allow manufacturers who 

choose to use bins such as Bins70, 50, 30 or 20 on an NMOG+NOx basis to earn early credits in 

the Federal program if they sold these same vehicles nationally. Again, the California 

certification conditions would apply (i.e., E10 and 150K useful life for Bin 70 and below unless 

it was a carryover SULEV meeting special conditions in California that would allow continued 

use of E0 and/or 120K useful life). 

Allowing certification to these NMOG+NOx LEV III/Tier 3 bins raises a question as to how 

such vehicles should be incorporated into the Tier 2 fleet averaging program which is based only 

upon NOx levels. The simplest solution would be to exclude these vehicles from the Tier 2 fleet 

average NOx computation. Since the above proposal would not include use of the LEV III/Tier 3 

bin160, all of the bins involved would have more stringent equivalent NOx emissions than the 

required Tier 2 fleet average level. 

Tier 2 Vehicles Tested on California E10: Finally, §86.113-04(a)(2)(ii) allows manufacturers to 

“certify 50-state vehicles based upon testing used to meet California’s LEV III standards” in MY 

2015 and later. However, paragraph §86.113-04(a)(2)(ii)(E) states that “such vehicles are 

considered to be Tier 2 vehicles for EPA certification; however, manufacturers must exclude 

them from the fleet-average NOx calculation in subpart S of this part.” On the surface, this 

proposal sounds similar to the option discussed above where vehicles that would actually be 

certified to LEV III/Tier 3 NMOG+NOx bins and then would be excluded from the Tier 2 fleet 

average. However, this provision applies to a totally different situation. 

This provision applies to the case where a manufacturer would be certifying Federal vehicles to a 

Tier 2 bin using E10 test data that was used for certification of the same vehicle in the California 

LEV III program. This would allow the manufacturer the ability to avoid a second test on 

Federal E0 just to demonstrate compliance with a less stringent Tier 2 bin. 

But EPA’s proposal to exclude such a vehicle from the Tier 2 NOx average would be 

counterproductive. This would prevent a manufacturer from being able to earn Tier 2 credits for 

vehicle being certified to Tier 2 bins 2, 3, and 4 simply because they chose the option to use the 

California test data to demonstrate compliance. Hence, if the manufacturer needed those credits 

to offset other vehicles certified to available Tier 2 bins above bin5, they would have to retest 

this vehicle on Federal E0. This defeats the purpose of allowing the use of California E10 test 

fuel in the first place. 

Also note that the above situation should only apply to vehicles that were certified in California 

to bins70 and below since in the affected MYs it is only these bins where California requires the 

use of E10. Vehicles in bin125 and 160 would still be allowed to certify on California phase 2 

E0, which EPA has historically accepted for Tier 2 certification purposes. Hence there would be 
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no relaxation of stringency in Tier 2 compliance if vehicles tested on California E10 where 

allowed to be counted in the Tier 2 fleet average. These would be vehicles designed for 

compliance with California bin70 or below but which would be certified in higher available Tier 

2 bins (i.e., most likely bin 3 or 4). 

The provision in §86.113-04(a)(2)(ii)(E) should be deleted as it defeats the whole purpose of 

having the (2)(ii) in the first place. 

Recommendation: EPA should consider simply comparing the sum of the 0-6,000 pound GVWR 

and 6-8,500 pound GVWR credits to the cap at the end of MY 2017. Also, EPA should revise 

the language on the computation of the early credit cap to be based upon the CA+177 State credit 

total and total sales rather than be based only upon only California credits and sales. Given the 

complexity of this issue, EPA should consider providing an example in the preamble to the final 

rule. 

To facilitate the ability to earn early credits, EPA should allow early certification to all of the 

LEV III/Tier3 bins below Bin160 under the same conditions that would be available in the 

California program for MYs 2015 and 2016. Such vehicles could be excluded from the Tier 2 

NOx fleet average to avoid issues with the fact that these vehicles would not have a separate 

NOx standard. 

Additionally, the provision in §86.113-04(a)(2)(ii)(E) should be deleted. 

American Honda Motor Co., Inc.

Another important aspect related to the harmonization of the Tier 3 and LEV III programs is the 

treatment of Tier 3 early credits. Honda strongly urges EPA to allow not just federally-certified 

Tier 2 vehicles, but interim Tier 3 vehicles, to generate early credits (calculated against the Tier 2 

standard) in model years 2015 and 2016. Doing so would accelerate nationwide adoption of 

cleaner emissions control technology prior to the formal introduction of Tier 3, improve 

automakers’ flexibility in meeting the standards in the early years of the Tier 3 program, and 

ease the transition toward more stringent standards as the program fully phases in. 

As EPA is aware, many automakers – including Honda – produce models certified to ULEV125 

in California (and Section 177 states), and certified to Tier 2 bin 5 (or Bin 160) federally. Given 

the short lead time, we believe it is not practicable to certify these models to the Tier 2 Bin 4 

(Bin 110) level in model years 2015 and 2016 while still maintaining a sufficient margin to 

ensure compliance across a mass-produced line. We do, however, believe there would be 

sufficient compliance margin to meet interim Tier 3 (Bin 125) levels, and that those models 

could thus see an accelerated nationwide deployment strategy at the cleaner Bin 125 level. For 

the purpose of generating early Tier 3 credits during the 2015 and 2016 model years, we see no 

sound reason for treating interim Tier 3 models differently than models certified to formal Tier 2 

bins. 

It is our understanding from conversations between EPA and OEM trade associations that the 

agency does not intend to reopen the Tier 2 standards; Honda understands the technical rationale 
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for that position, such as the lack of a separate NOx standard at the Bin 125 level. Barring 

changes to Tier 2 levels, we believe that an equitable, alternative resolution to this early credit 

issue is to allow early credits for interim Tier 3 vehicles, which could comply with Tier 3 using 

E15 or with LEV III using E10 and the accompanying 150,000-mile full useful life, and we urge 

the agency to do so. (We would further request that the agency, for clarification purposes, 

articulate whether interim Tier 3 vehicles earning early credits could use E0 and 120,000-mile 

full useful life, as those values are also consistent with the Tier 3 phase-in provisions.) 

The agency notes in the proposed rule that the early credit program is designed to accomplish 

three goals: 

(1) Encourage manufacturers to produce a cleaner federal fleet earlier than otherwise required; 

(2) provide needed flexibility to the manufacturers to facilitate the “step down” from the current 

Tier 2 Bin 5 fleet average required in MY 2016 to the LEV III-based declining fleet average in 

MY 2017; and (3) create a Tier 3 program that is equivalent in stringency to the LEV III program 

such that manufacturers will be able to produce a 50-state fleet at the earliest opportunity. 

Honda believes that allowing interim Tier 3 vehicles to generate early credits will improve the 

agency’s ability to obtain its stated early credit-related objectives, accelerating a 50-state 

deployment strategy, and bringing cleaner vehicles to market sooner than would otherwise occur. 

BMW of North America, LLC

CARB’s LEV III program allows the option to use combined NMOG+NOx for LEV II vehicles 

included in a manufacturer’s fleet average. The proposed Tier 3 language addresses the inclusion 

of the so called interim Tier 3 vehicles; however, allowing a combined NMOG+NOx standard is 

not entirely clear in the proposed language. BMW kindly requests clarification of the language 

such that MY 2015 and 2016 Tier 2 vehicles may certify to the combined NMOG+NOx 

standard. 

General Motors LLC (GM)

For the exhaust FTP NMOG+NOx fleet average, we support EPA’s innovative approach of 

allowing early credits and then capping them entering the 2018 model year in proportion to 

credits a manufacturer has in its California credit bank (or, as requested in the Alliance/Global 

comments, California + 177 State pooled credit bank). We believe this approach will address 

EPA’s three goals stated in the preamble: 1) encourage a cleaner Federal fleet earlier than 

required; 2) give manufacturers needed flexibility to go from Tier 2 to LEV III/Tier 3; and 3) 

make Tier 3 equivalent in stringency to LEV III to facilitate a 50-state fleet.

Under 86.113-04(a)(2) of the NPRM, EPA is suggesting a method for manufacturers to obtain 

nationwide certifications prior to the introduction of Tier 3. Essentially EPA will accept LEV III 

certifications as early as model year 2015, as long as the specified requirements are met. GM 

appreciates EPA’s allowance for manufacturers to execute nationwide applications; it’s a 

manpower savings and a reduction in complexity and is consistent with the goal of transitioning 

to a harmonized national program. The only concern GM has with the proposal is under 
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paragraph (ii)(B), which states: (B) The manufacturer must also use this E10 fuel for fuel 

economy measurements, with any appropriate corrections related to ethanol content in the fuel.

[EPA-HQ-OAR-2011-0135-4288-A1, pp.9-10] (ii)(B).

Our Response:

Several auto industry commenters suggested additional provisions to facilitate earlier 

harmonization between Tier 3 and LEV III and streamlining of development and certification of 

vehicle models. Specifically, these commenters requested the ability to have vehicles certified to 

the Tier 3 standards in MYs 2015 and 2016. They commented that this would allow them to 

develop, certify and sell a vehicle model for all 50 states, reducing the complexity of potentially 

different federal and California requirements in MYs 2015 and 2016. Additionally, auto industry 

commenters noted that the Tier 3 program provides more flexibility in the certification bin 

structure compared with the existing Tier 2 program, providing them additional opportunities to 

generate early credits.

We are finalizing a provision to allow manufacturers to certify to Tier 3 standards starting 

in MY 2015 as “Early Tier 3” vehicles. Manufacturers will have the option to certify their 

vehicle models to meet the Tier 3 emission requirements, including requirements for test fuel and 

useful life, in MY 2015 and 2016, and MY 2017 for vehicles over 6000 lbs. GVWR, for all 

LDVs, LDTs, and MDPVs, which otherwise would be required to begin in MY 2017 under the 

primary program. As an example, a manufacturer choosing to certify a vehicle as Early Tier 3 

can bring the same vehicle models certified to LEV III standards in MY 2015 or 2016 into the 

Early Tier 3 program by meeting all the same requirements under the primary Tier 3 schedule. 

There would not be a Tier 3 fleet average requirement for FTP or SFTP NMOG+NOx in MY 

2015 or 2016 (and 2017 for vehicles over 6,000 lbs GVWR) if all the same vehicle models 

certified to LEV III are also certified as the Early Tier 3 vehicles meeting the same LEV III 

emission standards and also the Tier 3 additional requirements (high altitude, and cold CO and 

hydrocarbons). These Early Tier 3 vehicles would replace any Tier 2 offering of the vehicle 

model consistent with the LEV III offering replacing the LEV II models. If a manufacturer 

chooses to certify only a portion of their LEV III vehicle models as Early Tier 3 vehicles in a 

given MY, they will be required to meet the LEV III fleet average requirements in that MY for 

those models certified as Early Tier 3 vehicles. 

The same carry-over provisions that begin in MY 2017 will also apply in MY 2015 and 2016. 

This includes the ability to carryover Tier 2 test results using Tier 2 fuel into the Tier 3 Bins 

above Bin 70. 

The early credit program we are finalizing includes several distinct provisions. The first 

provision allows manufacturers to generate early Tier 3 credits against the current Tier 2 Bin 5 

requirement in MYs 2015 and 2016 for vehicles under 6,000 lbs GVWR and MYs 2016 and 

2017 for vehicles greater than 6,000 lbs GVWR. We proposed and are finalizing a provision 

limiting the application of the early Tier 3 credits to the following conditions:

Early Tier 3 credits generated as described above could be used without limitation in 

MY 2017 on the portion of the fleet entering the Tier 3 program in that MY.
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Early credits generated from all vehicles in the light-duty program in MY2015 

through MY 2017 used for compliance in MY 2018 and beyond will be capped at an 

amount equal to the lesser of the manufacturer’s federal credits as calculated above or 

the manufacturer’s LEV III credits scaled up by the ratio of 50-state sales to 

California and LEV III required states sales. This limitation accounts for the fact that 

some LEV III credits may have begun to expire and will no longer be eligible as a 

basis for Tier 3 early credits.

By capping the available federal Tier 3 early credits, we believe that the two programs, 

LEV III and Tier 3 will be at parity in terms of relative stringency starting in MY 2018. In 

addition, because the number of Tier 3 early credits that can be used is based on the number of 

LEV III credits that the manufacturer has generated, there may be additional motivation for 

manufacturers to over-perform in California during the initial model years, accelerating emission 

reduction benefits.

The provision in §86.113-04(a)(2)(ii)(E) was deleted as suggested because the provisions 

we are finalizing provide for both Tier 2 and early Tier 3 in MY 2015, 2016 and 2017 

certification paths eliminating the issue of the LEV III combined NMOG+NOx standards not 

matching the Tier 2 independent NMOG and NOx requirements.

4.1.5.2. Credit Life and ABT

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

Credit Life (FR29868): We support the 5-year credit life and harmonization of this provision 

with California. We support the ABT program, which maintains program stringency while also 

providing flexibility. We also support harmonization of the credit life between EPA and 

California. 

Hyundai Motor Group

We also appreciate flexibilities included in the proposal, such as the ability to average across the 

fleet for most pollutants. Additionally, we support the averaging banking and trading provisions, 

which allow companies to obtain or sell emissions credits with other manufacturers, and the 

carry forward and back of credits, which are helpful flexibilities.

New York State Department of Environmental Conservation

Tier 2 vehicle emissions credits should not carry over to Tier 3. EPA proposes to prevent the use 

of existing Tier 2 credit balances to meet Tier 3 requirements. EPA also proposes to cap the use 

of early credits to comply with Tier 3. New York fully supports these provisions, which will 

expedite harmonization with LEV III and ensure that compliant vehicles are actually produced in 

the early years of the program. 
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The averaging, banking, and trading program is an important means of providing vehicle 

manufacturers with compliance flexibility. To that end we support credit carry forward and carry 

back provisions identical to those used in the LEV III program. 

Pennsylvania Department of Environmental Protection (DEP)

DEP supports flexibility for automobile manufacturers...through averaging, banking, trading 

programs, or other mechanisms. 

Our Response:

We did not receive adverse comments on our proposed design of the ABT program. We 

are finalizing these provisions as proposed, with one exception. Based on conversations with 

representatives of the auto industry, we determined that, with certain restrictions, Tier 3 credit 

life can be temporarily extended in a way that would address uncertainties about the middle 

years of the program, with no adverse impacts on the overall emission reductions of the program. 

Specifically, we are finalizing a credit life of 8 years for credits generated in MYs 2017-2022 for 

the FTP and SFTP NMOG+NOX fleet average standards. For the heavier light-duty vehicles, 

the 8-year credit life begins for credits generated in MY 2018. (Note that, as proposed, credits 

generated under the Early Tier 3 Credit provision (preamble Section IV.A.7.a) are limited to 5-

year life, and are not affected by the longer credit life provision.)

For credits generated in MYs 2023-2025, the credit life declines by one year of credit life 

annually, with credit life stabilizing at 5 years for credits generated in MYs 2025 and later. That 

is, credits generated in MY 2023 have a 7-year life, in MY 2024 a 6-year life, and in MY 2025 

and later a 5-year life. However, while credits can be generated, banked, and used internally for 

the extended time periods, credits cannot be traded to other manufacturers after 5 years.

4.1.5.3. Useful Life for Cold CO and Cold NMHC Standards

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

Cold CO and NMHC Useful Life: The preamble of the Tier 3 regulation states, “We are not 

proposing new emission requirements for any vehicle or fuel over the cold temperatures test 

cycles (i.e., the 20 °F cold CO and NMHC tests)’. We understand this language to mean that in 

addition to the exhaust emission standards for the cold CO and cold NMHC tests, there would 

not be any change in the useful life for cold CO and cold NMHC. The current useful life is 5 

years or 50,000 miles for cold CO and for cold NMHC is 10 years or 120,000 miles for LDV and 

LLDT and 11 years or 120,000 miles for HLDT and MDPV. The proposed regulations, however, 

do not carry over the language that specifies the current useful life for these standards. Based on 

the preamble language, it is not EPA’s intent to extend the useful life of the cold CO emission 
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test to 10 years or 120,000 miles (or 15 years/150,000 miles) under Tier 3, and therefore, the 

cold CO useful life language from §86.1805-12(d) should be added to the new section, 

§86.1805-17, to clarify the useful life for cold CO. Likewise, based on the preamble language, 

we believe that it is EPA’s intent to retain the cold NMHC standards at the current useful life 

requirements and would not apply the voluntary 15 years/150,000 miles standards for cold 

NMHC even if the vehicle is certified to 15 years/150,000 miles for the FTP and SFTP 

standards.

Thus, EPA should also add clarifying language to §86.1805-17 that cold NMHC useful life is not 

impacted. 

Recommendation: EPA should add the following language to §86.1805-17: 

“(f) Where cold CO standards are applicable, the useful life requirement for compliance with the 

cold CO standard only, is 5 years or 50,000 miles, whichever occurs first. 

(g) Where cold NMHC standards are applicable, the useful life requirement for compliance with 

the cold NMHC standard, only, is 10 years or 120,000 miles, whichever occurs first for LDV and 

LLDT, and 11 years or 120,000 miles, whichever occurs first for HLDT and MDPV.” 

Our Response: 

The useful life requirements for cold CO and cold NMHC standards are unchanged for 

Tier 3 and will remain the same as under the Tier 2 program. EPA has modified the language in 

§86.1805-17 to clarify the useful life requirements for cold CO and cold NMHC standards in a 

way that is equivalent to the commenter’s suggested language.

4.1.5.4. Enrichment Limitation

What Commenters Said:

California Air Resources Board (CARB)

Comment 1 - SFTP Enrichment Limitation Requirement 

CARB supports U.S. EPA’s Tier 3 proposal to reduce the tolerance of additional enrichment 

from six to four percent of the air to fuel ratio of Lean Best Torque. CARB believes the reduced 

tolerance is appropriate and feasible due to the improved fuel control utilized by today’s 

vehicles. CARB intends to propose alignment with this proposal once the Tier 3 program is 

finalized. 

Ford Motor Company (Ford)

Enrichment Limitation for Spark-Ignition Engines

EPA has proposed a new Lean Best Torque (LBT) definition, tolerance, and fixed spark mapping 

procedure designed to limit excessive in-use enrichment. Ford has several major concerns with 

this proposal: (1) there is no universally accepted “textbook” definition of LBT, (2) there is no 
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standardized engine mapping procedure to measure LBT, and (3) LBT can vary significantly 

depending on engine technology and the reference test fuel. For these reasons, we recommend 

that EPA carry over existing Tier 2 regulatory language (or adopt the LEV III LBT 

requirements) and establish a joint government / industry committee to determine a universally

accepted SAE LBT mapping procedure. This would help to ensure consistent, repeatable results, 

and enable an unambiguous interpretation of LBT between EPA and manufacturers even as 

engine and vehicle technologies evolve over time. 

Recommendation: Ford recommends that EPA retain the Tier 2 LBT requirements, or 

alternatively, adopt the LEV III requirements, until a universally accepted LBT definition and 

mapping process can be established by SAE. 

Our Response: 

The requirement to not exceed LBT +6% when SFTP standards were first adopted was 

based on variation in fuel and emission control hardware at that time. More stringent emission 

standards that have occurred since that time have resulted in reduced part variability that allows 

us to reduce the 6% tolerance to 4%. The LBT definition included in the FRM is to provide 

clarity regarding expected enrichment amounts and eliminate the risk that enrichment may 

interact with the control of ignition timing. Without this clarification, enrichment limitations can 

be interpreted differently and result in excessive emissions. The FRM allows for alternative 

definitions of LBT with approval if the finalized definition does not properly achieve the 

enrichment limitation goals of a unique technology.

4.1.5.5. AECD Requirements

What Commenters Said:

General Motors LLC (GM)

Expansion of AECD Requirements: EPA is proposing adding three additional requirements 

under paragraph (11) of 86.144-01: “Information requirements: Application for certification and 

submittal of information upon request.” 

(i) For any AECD uniquely used at high altitudes, EPA may request engineering emission data to 

quantify any emission impact and validity of the AECD.

(ii) For any AECD uniquely used on multi-fuel vehicles when operated on fuels other than 

gasoline, EPA may request engineering emission data to quantify any emission impact and 

validity of the AECD.

(iii) For Tier 3 vehicles with spark-ignition engines, describe how AECDs are designed to 

comply with the requirements of §86.1811-17(d). Identify which components need protection 

through enrichment strategies; describe the temperature limitations for those components; and 

describe how the enrichment strategy corresponds to those temperature limitations. We may also 

require manufacturers to submit this information for certification related to Tier 2 vehicles. 
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While the first two proposed requirements are within the scope of EPA’s current AECD 

regulations (“EPA may request additional data”), the third requirement (11)(iii) is an expansion 

of the current AECD required submissions. GM is opposed to this additional work for several 

reasons. This adds additional burden on manufacturers to produce this detail for every 

submission to EPA. This also falls under the same logic as the first two proposed additions –

EPA already has the authority to ask for this information from manufacturers as needed. Our 

biggest concern is the precedent this sets going forward for on-road spark-ignited applications. 

Today, the heavy duty diesel engine applications require a highly burdensome and detailed 

AECD submission. The work necessary to complete our heavy duty diesel engine AECD’s is 

easily a factor of 10 times the man-hours to complete compared to a similar on-road sparkignited application. Even with all the detail submitted for the heavy duty diesel engine 

applications, it’s often that EPA will ask for further clarification/detail. Our concern is the given 

proposal in the Tier 3 NPRM under 86.144-01 (11)(iii) is the beginning of a continual expansion 

of AECD submissions for light-duty that is unnecessary considering EPA already has the 

authority to ask for the given information. To place the whole industry in a position of spending 

the manpower to provide that information up front for every application is unnecessary and 

burdensome. 

Our Response: 

EPA currently has the authority to request additional data or information regarding any 

AECD to determine the validity of its use and to determine the impact on emissions. This 

information is something manufacturers should already have available as part of the certification 

process they perform in order to justify any AECD. The requirement that we are finalizing to 

report information that should be readily available to the manufacturer will add minimal 

additional work and allow the agency to better determine if industry-wide guidelines are being 

followed.

4.1.5.6. Carryover of Small Volume Test Group Data

What Commenters Said:

BMW of North America, LLC

To reduce the financial burden for small volume models and test groups, we propose allowing 

small volume test groups in the fleet to carryover certifying to Tier 2 standard and test fuel 

through MY 2021. 

Our Response: 

To reduce the burden of testing in the first years of the Tier 3 program, EPA has provided 

a mechanism that largely allows carryover of Tier 2 test data into the Tier 3 program through 

MY 2019 for exhaust and MY2021 for evaporative emissions. Consistent with LEV III, the new 

E10 test fuel will be required for all vehicle exhaust emission certification for MY 2020 and 
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later. Further delay of the Tier 3 program beyond the allowed provisions would restrict the 

opportunity for a harmonized program with LEV III, an important goal of the Tier 3 program.

4.1.5.7. DOR and Extended Warranty Credits

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

DOR Credit (FR29873): We support continuation of the DOR technology credit. 

Extended Warranty Credit (FR29873): We support the optional credit opportunity of 5 mg/mi for 

extending the vehicle’s warranty to 150,000 miles but do not believe that EPA needs to adopt 

California’s 4 percent recall provision in conjunction with this optional credit. 

Our Response: 

There were no adverse comments about either the DOR or Extended Warranty 

opportunities. We are finalizing these provisions as proposed, including no changes to the EPA 

recall provisions. 

4.1.5.8. Compliance Demonstration

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

The Alliance and Global Automakers share the goal of one national program that would allow a 

vehicle to be tested once, certified once and sold everywhere. Automaker and agency resources 

are limited, and it is critical that compliance efforts not be duplicated. To this end, we appreciate 

that the proposed Tier 3 regulations base fleet average emission requirements on nationwide 

vehicle sales rather than on non-Section 177 State sales. Given the current level of fleet average 

emissions, this is a reasonable flexibility that significantly reduces the resources needed to track 

and manage separate fleets. Similarly, LEV III allows manufacturers to comply with fleet 

average emission requirements based on sales in California and the Section 177 states. We intend 

to request that ARB modify the LEV III regulations to allow compliance on a nationwide basis 

consistent with Tier 3. 
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Compliance Demonstration Based on National Sales (FR29873): We support harmonization 

between EPA and California, including the goal of a single fleet, tested once, certified once and 

sold in all 50-states. Additional comments are provided in the written comment. 

National Automobile Dealers Association (NADA)

Harmonized Emissions Mandates, Lead Time, Durability and Other Technical Standards: Last 

year, the California Air Resources Board (CARB) finalized its Low Emission Vehicle (LEV) III 

regulations. In order to minimize compliance costs and maximize compliance flexibilities, EPA’s 

final Tier 3 regulations should encourage if not mandate that CARB harmonize with the federal 

scheme. Among other things, this means that fleet average emissions compliance should be 

based on a manufacturer’s nationwide sales. 

Our Response:

We received no adverse comments on our proposal to base fleet-average sales on a 

manufacturer’s nationwide sales, and we are finalizing this provision.

4.1.5.9. Aftermarket Catalysts

What Commenters Said:

Ozone Transport Commission (OTC)

California’s vehicle program includes updated aftermarket part rules that require catalytic 

converters to meet a 50,000 mile warranty and rely on a mass based standard, among other traits 

as outlined in OTC’s “Recommended Revisions to the Federal Aftermarket Catalytic Converter 

(FACC) Program.” EPA’s Tier 3 regulatory proposal does not include such an update to the 

FACC program. Without updating its policy, EPA would be allowing use of replacement 

converters that will not guarantee emission reductions as long as the original converters. To 

ensure emission reductions occur when catalysts fall outside of the warranty period, the final 

Tier 3 regulation should include a more stringent aftermarket catalytic converter policy as 

recommended previously by OTC. 

Our Response:

We did not propose and are not finalizing aftermarket catalyst requirements as suggested 

by the commenter. If EPA decides to pursue such a program, it will be through a separate public 

rulemaking process.

4.1.5.10. Treatment of FFVs

What Commenters Said:
Tier 3 Summary and Analysis of Comments

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Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

Flex-Fuel Vehicle (FFV) SFTP Certification Requirements – Testing on Gasoline and E85: The 

Tier 3 NPRM contains a new requirement that FFVs be tested using the SFTP on both gasoline 

and E85 (i.e., 85% ethanol). FFVs operating on gasoline almost always have higher SFTP 

emissions than when operating on E85. Consequently, to reduce what is a very burdensome test, 

current EPA Tier 2 and ARB LEV III regulations only require manufacturers to test FFVs using 

gasoline. Today’s new vehicles are already extraordinarily clean. Although we recognize the 

need for and support further emission reductions, automakers simply do not have the resources to 

pour into unnecessary tests such as those suggested in this portion of the NPRM. 

If EPA is concerned that FFV SFTP emissions would be higher if tested using E85 rather than 

gasoline, it could require that manufacturers test on the fuel that will result in worst-case 

emissions (based on the manufacturer’s good engineering judgment). This would satisfy EPA’s 

desire to ensure the vehicle would meet standards even when using the worst-case fuel. 

Finally, if EPA is unwilling to eliminate unnecessary tests and accept either of the above 

recommendations, it should at least allow manufacturers to substitute FTP emissions for SC03 

emissions. The SC03 test is particularly burdensome, and FTP emissions will be higher than 

SC03 emissions; allowing the substitution of FTP emissions instead of conducting SC03 testing 

would result in a worst-case condition. In fact, for these reasons, both EPA and ARB allow 

vehicles >8,500 pounds GVWR to substitute FTP emissions for SC03. 

Recommendation: EPA should eliminate the new requirement for manufacturers to conduct 

SFTP certification testing on E85. Instead, it should harmonize the Tier 3 and LEV III 

regulations specifying that SFTP testing of FFVs should be conducted using gasoline only. 

Alternatively, EPA could require manufacturers to certify over the SFTP on gasoline and then 

the manufacturer would attest that the vehicle will comply with the SFTP standards if operated 

on E85.

Regardless, for E85 testing, EPA should allow manufacturers to substitute FTP emissions for 

SC03 emissions. For in-use compliance testing, the manufacturer should have the option of 

running the actual SC03 rather than using FTP data for any test group.

California Air Resources Board (CARB)

SFTP Test Requirements for Fuel-Flexible Vehicles: CARB supports U.S. EPA’s Tier 3 proposal 

to require fuel-flexible vehicles to certify to SFTP standards using both gasoline fuel and the 

highest ethanol content fuel that a. given vehicle is designed to operate on. CARB believes this 

proposed requirement would ensure that emissions are controlled with all possible fuel blends 

and will propose inclusion of this provision in the LEV III program once the Tier 3 program is 

finalized. 

Renewable Fuels Association (RFA)
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In an effort to make Federal standards more consistent with California’s LEV III program, EPA 

is proposing new light-duty vehicle exhaust standards for NMOG, NOx and PM, as well as new 

evaporative emissions standards. Vehicle manufacturers have expressed serious concerns about 

the inability to certify emissions of FFVs under California’s LEVIII standards when those 

vehicles are operating on flex fuel. At issue is the fact that control of NMOG emissions during 

cold start conditions is more difficult on flex fuel due to the fuel’s volatility characteristics. Thus, 

when operating on flex fuel, NMOG emissions from FFVs tend to exceed NMOG standards 

before the catalyst is warmed up. The inability to certify FFVs under the California LEVIII 

program has resulted in greatly restricted sales of FFVs in the state. 

As EPA itself has acknowledged, the increased availability of FFVs is paramount to the 

successful implementation of the RFS. Thus, we encourage EPA to carefully consider how 

certification of emissions from FFVs should be handled. 

Our Response:

Because of the physical and chemical differences in how emissions are generated and 

controlled between vehicles operating on different blends of gasoline and ethanol, manufacturers 

of vehicles designed for high-percentage blends of ethanol (usually called Flexible Fuel 

Vehicles, or FFVs) may face unique compliance challenges under the Tier 3 program. 

Historically, under the Tier 2 program, FFVs have only been required to meet all Tier 2 emission 

standards, FTP and SFTP, while operating on gasoline (E0); when operating on the alternative 

fuel (generally this means a blend that is nominally 85 percent ethanol, or E85), they have only 

been required to meet the FTP emission standards. 

However, E85 use may rise considerably in the future as ethanol use increases in 

response to the Renewable Fuels Standards (RFS). Thus, as the Tier 3 program is implemented, 

it is increasingly important that FFVs maintain their emission performance when operating on 

E85 across different operating conditions.

We believe that at standard test conditions, requiring manufacturers to meet the Tier 3 

standards on any blend of gasoline and ethanol will not be significantly more challenging 

technologically than compliance on lower ethanol blends, including the E10 Tier 3 test fuel we 

are adopting. We are thus finalizing, as proposed, the requirement that in addition to complying 

with the Tier 3 requirements when operating on Tier 3 test fuel, FFVs also comply with both the 

FTP and the SFTP emission standards when operating on E85. This includes the requirement to 

meet emission standards for both Tier 3 test fuel and E85 for the FTP, highway test, and SFTP 

emission standards at standard test temperatures (i.e., 68 °F to 86 °F). Since FFVs can operate 

on any blend of gasoline and ethanol (up to a nominal 85 percent ethanol), the emission 

requirements apply to operation at all levels of the alternative fuel that can be achieved with 

commercially available fuels. However, for exhaust emission compliance demonstration 

purposes, we will test on Tier 3 test fuel and on fuel with the highest available ethanol content. 

Also, because gasoline and E85 have very different emission profiles, we are not allowing 

attestation of compliance on E85. 
Tier 3 Summary and Analysis of Comments

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To reduce the potential increase in test burden, EPA is (as recommended by the Alliance 

and Global) finalizing the provision to allow manufacturers to substitute FTP emissions for 

SC03emissions when submitting test data for certification to the SFTP composite standard for 

FFVs operating on E85. Manufacturers are still required to meet the SFTP standards if the SC03 

test cycle is used for the composite calculation. 

4.1.5.11. Applicability of FTP NMOG+NOx Standards to Highway Fuel Economy 

Testing

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

We support the proposed highway NMOG+NOx standards harmonized with California LEV III 

standards. 

Our Response:

We did not receive adverse comment on this proposed provision and we are finalizing it as 

proposed.

4.1.5.12. Preconditioning for Catalyst Desulfurization

What Commenters Said:

California Air Resources Board (CARB)

In response to reduced fuel sulfur levels in California and federal commercial gasoline, use of a 

sulfur purge preconditioning to reduce catalyst sulfur deposits prior to IUVP emission testing 

was disallowed by both CARB and U.S. EPA beginning in 2007. These purge procedures, which 

consist of high speed driving cycles not normally experienced as typical driving patterns, are 

designed to reduce sulfur and carbon deposits in the catalytic converter. Decreasing carbon build 

deposition in the exhaust system may have a positive impact on emissions but because carbon 

deposits are a result of real world driving conditions and fuel use, use of a sulfur purge procedure 

may produce a false representation of true in-use emissions. Nonetheless, the NPRM proposes to 

allow for conducting a sulfur purge cycle over the US06 test cycle for those manufacturers 

requiring a sulfur preconditioning test. 

Comment 2 - In-Use Verification Program Sulfur Purge Procedure for Sulfur Preconditioning. 

As noted above, sulfur content of federal commercial fuel has been significantly reduced and, 

based on past IUVP test data, manufacturers have not been allowed to perform sulfur purge 

cycles since 2007 and have not experienced any test vehicles failing to meet the exhaust 

emission standards that were attributed to high sulfur deposits. CARB believes running 
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additional sulfur cleanout procedures is unnecessary and should not be included as part of the 

IUVP or any in-use confirmatory test program. 

Ford Motor Company (Ford)

In-Use Preconditioning: While Ford agrees with the need for controls and specifications for 

IUVP preconditioning on light-duty vehicles and MDPVs, EPA’s proposed modifications to this 

process places additional restrictions on a manufacturer’s ability to mitigate sulfur contamination 

on in-use vehicles due to exposure to high-sulfur market fuel. These new restrictions come at a 

time when new, more stringent SFTP and PM requirements must be met and high sulfur fuel 

(>>10 ppm) will still be widely available. Also, this proposal does not provide the option to 

conduct a sulfur purge cycle for any emission constituent other than NMOG + NOx on the FTP 

or HFET cycle. Ford believes that sulfur contamination also poses significant risks for CO and 

PM, on the FTP cycle, and NMOG +NOx, CO, and PM on the SFTP.

Additionally, the Tier 3 IUVP preconditioning proposal requires an in-tank fuel sulfur 

assessment before allowing additional preconditioning cycles. Since most contract and OEM labs 

do not have in-house fuel sulfur measurement capabilities, fuel samples must be sent to off-site 

laboratories for testing, which could result in impractically long delays for IUVP retests on 

customer vehicles. 

Finally, because sulfur contamination on gasoline catalysts is a cumulative effect, a spot check of 

the fuel in the customer’s tank just prior to an IUVP test captures at best the last 0-400 miles of 

operation, and is insufficient to ensure that a vehicle has not been impacted by exposure to highsulfur fuel. 

Recommendation: In light of these issues, Ford proposes that EPA carry over existing Tier 2 

IUVP protocol, eliminate the fuel sulfur check requirement, and include new, forward-looking 

IUVP retest provisions for NMOG+NOx, CO, PM, and N2O with new E1x test fuel on all IUVP 

test cycles . Additionally, for IUVP FTP and SFTP PM measurements, we request that EPA 

allow OEM’s to use good engineering judgment to optionally average multiple tests to determine 

PM compliance thru 2025MY. 

General Motors LLC (GM)

Preconditioning for In-Use Testing: 86.1845-04 (a)(3) outlines provisions on how to address 

potential residual effects of sulfur contamination on in-use vehicle testing. While we’re grateful 

EPA recognizes the impact of sulfur poisoning on in-use vehicles, these provisions either do not 

adequately address the sulfur poisoning or are impractical to implement. 

EPA goes into great detail about the impact of sulfur poisoning on in-use vehicles in section 

(IV)(A)(6)(a) of the NPRM, and in sections (IV)(A)(6)(b) through (c), EPA discusses the effects, 

impacts and controls regarding emission standards on vehicles impacted by sulfur. The 

information provided by EPA is very compelling and obvious – sulfur does impact in-use 

vehicles negatively and can prevent manufacturers from meeting standards. EPA also 

demonstrates that, while not completely effective, preconditioning vehicles to properly burn off 
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some (not all) of the sulfur poisoning effects can significantly improve catalyst performance. 

Without a preconditioning step, EPA states that “Any degradation in catalyst performance due to 

gasoline sulfur would reduce or eliminate the margin necessary to ensure in-use compliance with 

the proposed Tier 3 emissions standards.” 

With this in mind, GM does not understand the resistance of EPA to allow preconditioning of inuse vehicles prior to formal in-use testing. Granted EPA is proposing that manufacturers could 

take a fuel sample of the as-received candidate vehicle and use that as potential evidence that 

retesting is applicable, but this raises several questions. What if the sample is lost? What if the 

sample is mislabeled? Do we really want to add the burden of in-use testing by handling a very 

volatile and hazardous liquid? By no means is this fuel sample conclusive of the vehicle’s sulfur 

poisoning level. The customer could have easily poisoned the catalyst on previous fuel, and now 

have a tank of low sulfur fuel. 

Moreover, there are numerous practical issues associated with EPA’s proposed approach. For 

example, taking a fuel sample of every vehicle that is brought in for in-use testing would add 

time and cost to an in-use test program. 

The final concern is that sulfur levels in the U.S. will be phased down over multiple years, while 

this requirement takes effect with the final rule. This means field fuel will continue to have high 

sulfur levels in the market. Even when low sulfur levels have been fully phased-in, how can we 

be sure that a given refinery hasn’t had a “spill” and released fuel with high levels of sulfur? 

When vehicles are to meet the stringent Tier 3 standards, any degradation such as sulfur 

poisoning can have significant effects. 

We believe EPA wants “real world” testing results, but manufacturers should not be held to 

comply based on factors they cannot control (i.e., high sulfur fuels). As for real world testing 

results – that’s a different scope than manufacturer in-use testing for compliance. In-use 

compliance testing should be conducted in a technically sound, repeatable and accurate manner 

similar to the original certification process, and manufacturers should not be held accountable for 

factors beyond their control. 

GM proposes allowing manufacturers to conduct either on-road or lab preconditioning of in-use 

vehicles. Not only will this help mitigate the effects of sulfur poisoning, it will also allow 

manufacturers to check for any other unforeseen issues with an as-received customer vehicle 

(e.g., mechanical soundness, operating properly, etc.). 

Volkswagen Group of America, Inc.

Tier 3 proposes to limit the OEM ability to use fuel enrichment in calibration. This restriction 

effectively increases the stringency of Tier 3 because it is now harder to clean the sulfur off the 

catalyst. If EPA is unwilling to mandate a 10 ppm cap in market fuel sulfur, OEMs must 

continue to be allowed to condition the sulfur off the catalyst prior to any In-Use exhaust testing. 

The market fuel will be high enough in sulfur to poison the catalyst. Two US06 cycles on the 

proper cert fuel will be required to overcome the market fuel and its effects. Vehicles should not 

be punished because they are operating in an environment of suboptimal fuels. EPA’s own data 
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shows the need for this preconditioning. Mirroring the sulfur purge cycles that EPA used before 

conducting its sulfur studies, purge cycles are needed for In-Use compliance on high sulfur 

market fuel. With credits and the high proposed allowable pump sulfur levels, two USO6 cycles 

are necessary to remove the catalyst poisoning sulfur. This should be the procedure implemented 

without any monitoring of the fuel in the tank of the vehicle or other burdensome requirements. 

Mercedes-Benz USA, LLC on behalf of Daimler AG

Mercedes-Benz requests that the EPA also include in its final Tier 3 rulemaking, a pre-test 

catalyst conditioning procedure to be performed prior to in-use vehicle testing, which design is 

mutually agreed upon by Mercedes-Benz and the EPA, in order to minimize the magnitude and 

frequency of ‘sulfur burn off’ cycles required in normal operation. This will provide real-world 

benefit to the consumer in optimized fuel economy and reduced GHG emissions. 

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

The Tier 3 rulemaking is the correct place to set the near-term standards for sulfur and also 

create a roadmap of how the agency will further reduce sulfur in the coming years. EPA should 

specify that catalyst burnoff cycles are allowed for Tier 3 In-Use Testing. 

Our Response:

Based on our findings from the In-use Sulfur Test program, we firmly believe that in 

order for Tier 3 vehicles to perform at their designed emission levels, they will need to operate 

in-use on fuels at sulfur levels that average 10 ppm or less. However, during the transition from 

30 ppm average sulfur levels and the possibility of higher sulfur levels that could be encountered 

due to the Tier 3 fuel 95 ppm sulfur cap extending past the transition, vehicles emission

performance could be adversely impacted which would be demonstrated during IUVP emission 

testing. To address this issue, we are including a provision that allows manufacturers to retest a 

vehicle if it has failed the initial “as received” tests during IUVP emission testing. The provision 

allows for a limited and reasonable sulfur clean-out based on Tier 2 experiences, and an 

additional requirement to provide potential proof of high sulfur exposure, typically from a fuel 

sample of “as received” vehicle fuel. 

We do not believe allowing sulfur related preconditioning, either EPA prescribed or 

manufacturer determined procedures prior to “as received” testing is appropriate as it may distort 

the “real world” emission performance evaluation related to sulfur or other vehicle factors. This 

initial “as received” emission performance information is critical to evaluating the emission 

performance of the vehicle on design intent fuel and additionally to determine if in-use sulfur 

levels are supporting expected emission reductions. We acknowledge that the requirement to 

provide evidence that the vehicle has operated on elevated fuel sulfur levels potentially adds an 

additional step in the IUVP process, however we believe it is important to attribute any emission 

increases or failures to the proper root cause so that we may determine if future actions are 

required, including tighter control of in-use fuels.
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4.1.5.13. Cold-Start Emissions; Start-Stop as Potential Tier 3 Technology

What Commenters Said:

Private Citizen

Going forward, there were a couple of things I had concerns with. A lot of the car companies 

don’t seem to be interested in dealing with the pollution before a catalytic converter warms up, 

the so-called open loop phase. And I’m wondering if that could be included in some of your 

thinking. Perhaps something could be included where an auto maker might get credit for a start 

and stop system whereby if someone is at a drive-thru, instead of polluting, the car would just 

stop automatically, and thereby wouldn’t pollute, and perhaps could get credit if they didn’t 

completely meet some of these other tough standards.

Our Response:

The Tier 3 standards, particularly the NMOG+NOx standards, require manufacturers to 

pay careful attention to cold-start emissions and design their control systems to address 

emissions prior to catalyst light-off. Regarding start-stop technology, the impact of these 

systems on CO2 emissions can be significant, but NMOG+NOx and PM emissions that are the 

focus of the Tier 3 program are less impacted by reducing idle operation and will be accounted 

for in the Federal Test Procedure.

4.1.5.14. Cold Durability Testing

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

Cold Testing Requirements for Emissions Durability Vehicle: For emission data vehicle (EDV) 

selection, Tier 2 currently requires that manufacturers select the vehicle expected to emit the 

highest CO emissions at 20°F on candidate in-use vehicles from the test vehicles selected. The 

proposed Tier 3 regulations add another test based on the worst-case cold NMHC in §86.1828-

01(g). EPA recognizes that the expected worst-case cold CO vehicle could be the same as the 

expected worst-case cold NMHC vehicle, and only testing on one vehicle would be required. 

However, we see little benefit, but significant cost, to potentially testing two separate vehicles 

based on different criteria pollutants. The 75°F FTP and SFTP tests are based on a more general 

“worst-case tailpipe emissions’ (11). We believe this is appropriate for 20°F testing as well. The 

recommendation below parallels the SFTP and FTP language in §86.1828-01(a). 

Recommendation: We recommend deleting proposed new paragraph §86.1828-01(g), and 

instead modifying §86.1828-01(c) as follows: 
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(c) Cold CO 20 degrees F testing. For cold temperature CO 20 degrees F exhaust emission 

compliance for each durability group, the vehicle expected to emit the highest CO emissions at 

20 degrees F be worst-case for exhaust emission compliance on candidate in-use vehicles shall 

be selected from the test vehicles selected in accordance with paragraph (a) of this section. 

Our Response:

We do not believe this modification is appropriate for evaluating worst case candidates 

and are finalizing these provisions as proposed. We do not believe that this change will 

necessarily require the added burden of separate testing for each of the emission requirements 

however it is clear to us that the relationship between CO and NMHC is not as clear as other 

worst case emission determinations and involves a variety of factors. These factors may include 

design difference that asymmetrically impact one emission and not the other (e.g. battery size 

and cranking system impacts NMHC but not CO). Additionally, the relative compliance margin 

and approach to these two requirements are very different with Cold CO standard as a fixed cap 

with typically large compliance margins and cold NMHC as an FEL possibly requiring 

manufacturers to test different vehicles.

4.1.5.15. Diesel Bench Aging

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

Due to the lack of diesel bench aging, certification of diesel vehicles under Tier 2 is resource and 

time intensive as a result of maintaining and testing early prototype vehicles for 120,000 miles. 

A regulatory provision for diesel bench aging approval is requested to support the incremental 

durability work associated with 150,000 mile standards under Tier 3. The Alliance and Global 

Automakers recognize that before individual manufacturers can obtain approval for diesel bench 

aging, the EPA will need the industry to develop and submit a publically available bench aging 

procedure that the agency approves. A comprehensive industry group has been formed to 

develop this procedure and work with the EPA to create a mutually agreeable bench aging 

procedure for diesel components. Since the industry has now accepted the responsibility for 

developing the required procedure, the Alliance and Global Automakers respectfully request that 

the EPA insert language into the Tier 3 regulation that specifically allows diesel bench aging 

pending approval of the industry developed bench aging procedure. Allowing diesel bench aging 

in the Tier 3 regulation, avoids the need for an additional rulemaking, streamlining the process 

for diesel bench aging approval, and saving time and resources in the future. 

Mercedes-Benz USA, LLC on behalf of Daimler AG

A bench aging durability procedure should be allowed for diesel-fueled vehicles as it is allowed 

for other light-duty vehicles, light-duty trucks, and medium-duty passenger vehicles. Under the 

current Tier 2 provisions, certification of diesel vehicles is both time- and resource-intensive due 
Tier 3 Summary and Analysis of Comments

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to the lack of diesel bench aging. In order to achieve the necessary mileage without bench aging, 

early prototype vehicles must be maintained and tested for 120,000 miles, resulting in additional 

costs and testing time. These costs would only be higher for a useful life of 150,000 miles under 

the Tier 3 provisions. As noted in the comments submitted by the Alliance of Automobile 

Manufacturers, which we support, a comprehensive industry group has already been formed to 

develop information regarding the feasibility of the standard certification test procedure. 

In the Tier 3 Proposed Rule, EPA references the existing exhaust emission bench aging 

durability programs allowed under 40 C.F.R § 86.1823-08 and the evaporative bench aging 

durability programs allowed under the provisions of 40 C.F.R § 86.1824-08. 78 Fed. Reg. at 

29,908. Allowing diesel bench aging would simply be an expansion of existing programs, 

tailored as appropriate to diesel-fueled vehicles and similarly requiring the use of good 

engineering judgment in the design of the bench aging program. 

Since the introduction of EU5 standards in the European Union (‘EU’) in 2009, the EU reviewed 

and fully adopted the EPA bench aging procedures for gasoline light-duty vehicles. This process 

allowed maintaining of separate EU standards but coordination of the EU and U.S. procedures. 

The EU, with a larger diesel share, also adopted a diesel bench aging procedure which has been 

used by manufacturers and confirmed by the EU since 2009. Moreover, from the development of 

the new world harmonized light-duty test procedure (‘WLTP’), where EPA is also a member, 

real world driving data of U.S. citizens are certainly demonstrated as being comparable to EU 

driving patterns. Accordingly, the EU diesel bench procedure has proven it is able to demonstrate 

real world aging of aftertreatment systems under U.S. real world driving conditions, as is the 

case for the gasoline procedure. EPA’s inclusion of similar provisions would be consistent with 

past EU practice and would help implement this Administration’s global harmonization initiative 

as evidenced by the Transatlantic Trade and Investment Partnership. Development testing of 

U.S. diesel engines to U.S. standards using EU bench aging protocol shows that diesel bench 

aging is an effective way of ensuring compliance efficiently. 

For all of these reasons, diesel bench aging should be allowed under the Tier 3 regulatory 

provisions. If EPA has any concerns regarding issuance of a bench aging approval in the final 

Tier 3 rule, subject to manufacturer guidance in accordance with existing bench aging regulatory 

requirements, EPA should immediately initiate a supplemental notice or direct final rulemaking 

to allow diesel bench aging, the completion of which should be timed to coincide with the 

finalization of the Tier 3 provisions. 

Volkswagen Group of America, Inc.

Diesel bench aging is necessary for streamlining resource-intensive activities. OEMs need a 

procedure that is well developed with a collective of manufacturers. Tier 3 needs to allow 

options like these for the future. VWGoA specifically requests that Diesel bench aging be 

included in the Final Tier 3 rule. We understand that EPA needs an Industry supported and 

publically vetted procedure. A group of more than 8 OEMs have agreed to work together to 

create a logical, useful bench aging procedure. With the increase to 150k miles full useful life, 

demonstrating emissions durability using on-road procedures is too expensive and cumbersome. 

Currently Diesel vehicle families are not equivalent to gasoline families and require a full, 

separate demonstration. In the future, compliance to GHG and Fuel Economy rules may mean a 
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larger portion of our fleet may include Diesel options, and creating a streamlined approach to 

bench aging components will be necessary. 

Our Response:

Although EPA appreciates the industry interest in a diesel bench aging protocol, in the 

absence of an industry-consensus approach, we do not believe it would be appropriate to take 

action as a part of the Tier 3 rule. EPA will monitor industry progress in this area and consider 

action at an appropriate future time. 

4.1.5.16. Diesel Emissions Fluid Refill Intervals 

What Commenters Said:

Volkswagen Group of America, Inc.

Diesel Emissions Fluid (DEF) is the primary method of controlling diesel emissions and marks 

the first time the driver is integral to the function of the vehicle emission controls. In VW Group 

vehicles the driver receives multiple escalating warnings including preventing vehicle start for 

not keeping the fluid reservoir at proper levels. A recent Heavy Duty study in California (1) 

shows that vehicles (drivers) are filling up the tanks, and when they don’t, the inducements are 

working. Mandating a large mileage interval between fills results in a large fluid capacity and 

adds unnecessary weight to the vehicle. Current regulations tie the oil change interval to the DEF 

refill interval; decoupling DEF fill from oil change interval allows more compliance options and 

easier packaging of smaller systems. The stringency of Tier 3 will require more DEF 

consumption. This means that the storage tanks will either have to increase in capacity or we 

must needlessly shorten oil change interval, and thus require the customer to change their oil 

more often. Allowing a shorter refill interval will help optimize vehicle design for the multitude 

of functional objectives. VW views this as a critical issue, as it risks not being able to give the 

driver the best ownership experience. We do understand that this is not directly included in the 

Tier 3 NPRM, but feels that it can be included in the Final Rule. [EPA-HQ-OAR-2011-0135-

4299-A1, main comment pp. 1-2]

Our Response:

As noted by the commenter, this comment is not within the scope of the Tier 3 rule.

However, EPA plans to finalize a separate rule to address this issue. On June 8, 2012, EPA 

proposed a rule to codify SCR maintenance (77 FR 34149). The EPA is close to finalizing that 

rule and addressing all comments received, including comments about the connection between 

Tier 3 compliance and DEF tank sizes, as well as comments about de-linking DEF refill intervals 

from oil change intervals.

4.1.5.17. Manufacturer In-Use Verification Testing (IUVP) Requirements regarding PM
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What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

In-Use Verification Program (IUVP) PM Testing at Low Mileage: We do not believe low 

mileage IUVP PM testing is an efficient or effective use of resources. If there are going to be 

compliance problems, it is either going to be with fundamental vehicle calibrations where 

compliance can be demonstrated as sufficient during certification testing or it is going to be due 

to a high mileage deterioration issue, which would not show up during low mileage IUVP testing 

anyway. However, EPA has said it wants to see low mileage IUVP data for PM to be assured 

inadequate designs (calibrations) did not make it past certification especially given the newness 

and stringency of the proposed PM standards. 

We appreciate that EPA has attempted to reduce the burden of IUVP PM testing by proposing 

that automakers only be required to test roughly half of all IUVP test vehicles for PM, and we 

support this approach. However, given the substantial burdens of PM testing, we have two 

significant concerns with the proposed low-mileage PM IUVP testing requirements. One is the 

excessive burden of having to perpetuate low mileage PM testing after manufacturers have 

demonstrated that certain fundamental vehicle designs will perform well below the standards 

based upon certification and initial low mileage in-use testing. The other -- and more immediate -

- concern is the near term cost and lead time issues with converting IUVP testing facilities so 

quickly after doing a major conversion of development testing facilities and virtually all 

certification testing facilities. 

While we do not agree that low mileage PM testing will be cost-effective, if EPA is going to 

insist on low mileage in-use testing for an initial screening purpose, it does not seem that regular 

low mileage IUVP testing needs to be perpetuated. The current IUVP regulations allow the 

agency the discretion to reduce IUVP testing as a manufacturer has demonstrated good in-use 

performance. However, for non-PM IUVP testing, manufacturers have demonstrated excellent 

in-use compliance now for over 10 years of IUVP testing, and the agency has never exercised 

authority to reduce testing burdens despite industry requests. Hence, without more specific test

burden reduction criteria being built into the regulations, we would have to assume the same 

thing would occur with PM testing, whereby the agency would never move to reduce burdens, 

even after a number of years of demonstrated good in-use performance even at low mileage. 

The Agency should be able to conclude that a general design approach (i.e., a given generic fuel 

injection/engine design approach) assures compliance at low mileage based upon certification 

testing followed by fairly limited low mileage IUVP confirmation. One specific design approach 

where low mileage IUVP testing will certainly result in limited benefits is gasoline PFI vehicles. 

In fact, almost all reported data indicates that the gasoline PFI vehicles have remained well 

below the 3 mg/mi standards, and historically EPA has waived all testing for these vehicles. 

Adding testing oversight that will occur in certification alone should be sufficient for these 

vehicles. The very few concerns that have been noted with PFI vehicles have been associated 

with higher mileage deterioration, such as potentially with oil consumption, which would not be 
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seen during low mileage IUVP tests. Hence, low mileage testing should be completely waived 

for PFI vehicles. 

Additionally, other fundamental design approaches should be able to forgo additional low 

mileage PM testing after they have gone through a single round of low mileage IUVP testing 

without there being any indication of a problem (i.e., if initial IUVP testing validates what was 

observed in certification testing). At the very least, a test group that is certified based upon 

carryover data and which has been validated once in low mileage IUVP testing should not be 

subject to additional low mileage testing as long as carryover continues. Language should be 

included in the regulations that would allow the manufacturer to request a waiver of the IUVP 

low mileage PM testing for test groups that it can demonstrate use essentially the same fuel 

injection, engine design, and PM control characteristics as another test group which has 

undergone successful low mileage IUVP testing once. Actually, we recommend that similar 

language be included in IUVP that would similarly allow reduction of low mileage IUVP testing 

for all other pollutants as well. But it is most important for PM testing given the added burdens 

and added risks of voided tests associated with the much more challenging PM test procedures. 

Furthermore, the IUVP low mileage requirement follows so quickly after the beginning of the 

Tier 3 program that manufacturers will have to begin conversion of IUVP testing facilities before 

they have even completed the substantial phase in of new testing facilities needed for 

development and certification. Given the standards phase in with only 10 to 20% of a 

manufacturer’s fleet needed to comply in MY 2017, we acknowledge that there will not be many 

tests groups that will be subject to low mileage IUVP testing at the end of that first one or two 

compliance years. However, even with only a few tests being needed, the test facility 

modifications to accommodate PM testing will have to be in constructed. Many manufacturers 

perform IUVP testing at physically different locations than where development or certification 

testing is performed. Hence, the “few” initial low mileage test groups cannot be easily tested 

using the new facilities that would have just been put into place for certification testing. To 

minimize the burdens associated with converting so many facilities at nearly the same time, we 

ask that EPA grant extra lead time for establishing IUVP testing capabilities by waiving the low 

mileage PM testing requirement for the first two model years as the PM standards phase in. 

High mileage IUVP testing would be retained as proposed, so minimization of low mileage 

testing would not let manufacturers escape ultimate recall liability. Hence, manufacturers cannot 

afford to be careless or try to game their way through certification and minimal low mileage 

testing. Additionally, if low mileage testing were waived for the first two years of the program, 

the test groups that would be waived would not totally escape testing prior to high mileage 

testing, since many such test groups would likely be carry-over groups for the next couple years 

(i.e., many of these would end up being tested under subsequent model year low mileage testing 

requirements). 

Recommendation: We recommend that EPA include language in the low mileage IUVP 

regulations that would minimize the need to perpetuate low mileage PM testing for vehicles that 

have demonstrated good performance via certification and initial low mileage testing. 

Specifically we recommend: 

• Completely waiving of the requirement for low mileage testing of gasoline PFI vehicles. 
Tier 3 Summary and Analysis of Comments

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• Waiving testing of carryover test groups that demonstrated compliance in their first model year 

of low mileage testing. We specifically recommend this test reduction for low mileage PM IUVP 

tests but suggest that it would be equally important and appropriate for low-mileage IUVP 

testing of other criteria emission pollutants. 

• Including a provision where a manufacturer may request the waiver of low mileage testing for 

test groups having similar PM reduction design characteristics as other test groups that have 

undergone successful low mileage testing. 

Additionally, EPA should delay the applicability of low mileage IUVP PM testing requirement 

until after the first two model years of the PM standards phase-in. 

Our Response:

As noted by the commenter, EPA proposed and is finalizing a provision to significantly 

reduce the burden of IUVP testing PM measurement by requiring roughly half of all IUVP test 

vehicles measure PM emissions. We believe that it is important to closely monitor the PM 

emissions from the future Tier 3 vehicles given the importance of PM emissions reductions to 

the Tier 3 program and the associated health benefits. The requirements that we are finalizing 

for low mileage testing are reasonable and necessary to provide an early opportunity to ensure 

that PM levels observed at certification are consistent with in-use performance. As described in 

the comment, the current IUVP regulations allow the agency the discretion to reduce IUVP 

testing as a manufacturer has demonstrated good in-use performance. 

While we observed a general trend of certain mature technologies (i.e. gasoline PFI) 

performing better than others in our feasibility study, we believe 

that the changes in vehicle designs in response to items such as GHG/FE standards and customer 

preferences will not guarantee that future vehicle designs will maintain the same PM 

emission performance regardless of technology maturity. We feel that enough changes can 

occur year to year such as in the emission controls and 

calibrations to justify the reasonable and limited low mileage PM testing finalized for Tier 3. 

Additionally, manufacturers have not provided sufficient evidence in certification or in-use that 

the levels of the new PM standards, particularly for SFTP US06, are consistently being 

demonstrated by any technology, including the mature technologies discussed in their comments. 

In other words, statements regarding the relative maturity of technology and its associated PM 

performance are based solely on the limited data made public by EPA and CARB and 

commenters did not provide a single piece of low mileage test data on any technology that would 

conclude additional reductions in PM measurement are justified, particularly for the SFTP US06 

test cycle 

We reject the notion that manufacturers require more time to prepare emission 

measurement testing facilities for the already reduced amount of PM testing that will be required. 

In fact, the phase-in of the Tier 3 PM standards is structured in recognition of the issue of testing 

facilities availability and associated burden in the early years as discussed in the preamble and 

less concern about feasibility since manufacturers have the ability to select the vehicles and 

technologies in which they have the most confidence in the early years.
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4.2 Tailpipe Emissions Standards for Heavy Duty Vehicles

4.2.1. HDV Program Lead Time

What Commenters Said:

Truck and Engine Manufacturers Association (EMA):

Leadtime, Stability and Technical Feasibility:

As established by the Clean Air Act, any mobile source emission standards adopted by EPA for 

on-highway engines and vehicles above 6,000 lbs. GVWR must be technologically feasible and 

may be implemented, among other things, only if the requisite leadtime and period of stability 

are provided to manufacturers.

CAA Section 202(a) requires, among other things, that emission standards for heavy-duty 

engines must be technologically feasible:

[S]tandards must reflect the greatest degree of emission reduction achievable through the 

application of technology ... determine[d to] be available for the model year to which such 

standards apply, giving appropriate consideration to cost, energy, and safety factors associated 

with the application of such technology.

CAA Section 202(a)(3); 42 U.S.C. §7521. See Motor & Equip. Mfrs. Ass’n v. EPA, 627 F.2d 

1095, 1111 (D.C. Cir. 1979) (consistency with the CAA requires standards to be 

“technologically feasible”). EPA has failed to justify the technological feasibility of many of the 

proposed requirements, specifically those relating to the lack of interim in-use and high-altitude 

standards for medium- and heavy-duty vehicles and engines.

Engine manufacturers also need sufficient time to develop technology that is feasible and 

practical. Section 202(a) of the CAA specifically requires EPA to provide sufficient leadtime 

and an adequate period of stability for any standards affecting new on-highway engines and 

vehicles above 6,000 lbs. GVWR:

Any standard promulgated or revised under this paragraph and applicable to classes or categories 

of heavy-duty vehicles or engines shall apply for a period of no less than 3 model years 

beginning no earlier than the model year commencing 4 years after such revised standard is 

promulgated.

In other words, any new emission standards may go into effect only four or more full model 

years after the year in which they were promulgated. And, all new or previously-adopted 

standards must stay in effect for at least three full model years before EPA may establish another 

applicable standard.

For vehicles and engines over 6,000 lbs. GVWR, which are subject to those leadtime and 

stability requirements, EPA has proposed both “primary” and “alternative” paths to compliance: 
Tier 3 Summary and Analysis of Comments

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one path that phases in fleet average standards (which become more stringent in successive 

model years) over a period of several years and an alternative path that requires a percentage of a 

manufacturer’s product to be phased in to far more stringent emission standards along a much 

more aggressive timetable. The standards and phase-ins for the categories of vehicles and 

engines above and below 8,500 lbs. GVWR are different, but each category has similar 

“primary” and “alternative” paths.

In both categories (above and below 8,500 lbs. GVWR), the “primary” path fails to provide four 

full model years’ leadtime and three years of stability. Meanwhile, while the “alternative” path 

meets minimum leadtime and stability requirements, the “alternative” path standards are not 

technologically feasible. EPA has provided manufacturers with a “choice” that is effectively no 

choice at all: manufacturers must choose one of two alternatives, neither of which meets the 

statutory requirements of the CAA.

The comments of the Alliance outline in greater detail the issues and impacts associated with 

EPA’s failure to provide four full model years’ leadtime for those categories of vehicles under 

8,500 lbs. GVWR. For vehicles and engines in the 8,501-14,000 lbs. GVWR range (“HeavyDuty Vehicles”), EPA has proposed declining fleet average standards that begin in 2018 through 

2022, with an “alternative” phase-in percent of sales requirement that begins in 2019 for “any 

manufacturer who prefers a stable standard and four full years of lead time, as specified in the 

[CAA].” (78 Fed. Reg. at 29876; emphasis added.) EPA’s failure to provide sufficient leadtime 

and stability in those proposed declining fleet average standards is not a matter of “preference” 

but a matter of law – as established in the CAA. And, while standards that begin in 2019 

technically would provide the legally-required four model years’ leadtime (assuming the 

Proposed Tier 3 Standards are finalized before the end of 2013), EPA has failed to demonstrate 

that the proposed standards of the “alternative path” are technically feasible for Heavy-Duty 

Vehicles.

For example, in support of its decision to exclude interim in-use standards for vehicles over 

8,500 lbs. GVWR, EPA only used data generated from two medium-duty vehicles which were 

not aged to 150,000 miles full useful life and were not representative of the vehicles that will be 

needed to meet new, stringent GHG standards for heavy-duty vehicles. EPA also referred to 

light-duty vehicles with powertrains similar to their heavy-duty counterparts as support for the 

lack of interim in-use standards. Yet, in apparently relying on such light-duty data, EPA did not 

account for the additional technical challenges associated with meeting the proposed standards at 

adjusted loaded vehicle weight (ALVW). As EPA has noted in the preamble to the Proposed 

Rule, emissions from Heavy-Duty Vehicles are tested with loaded vehicles to ensure the 

emissions are controlled when such vehicles are performing their core function: hauling heavy 

loads. (78 Fed. Reg. at 29874.) Heavily-loaded vehicles have different emission characteristics 

from vehicles under light load. Thus, light-duty vehicles not tested at ALVW cannot and should 

not be relied on for demonstrating the technological feasibility of standards applied to heavier 

vehicles at ALVW.

EPA must meet its obligations to propose and finalize regulations that it can demonstrate are 

both technologically feasible and provide the necessary leadtime and period of stability required 
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by the CAA. EPA has not done so with either the primary or alternative standards for vehicles 

greater than 6,000 lbs. GVWR. 

Chrysler Group LLC:

NMOG+NOx Phase-In Requirements for Heavy-Duty Vehicles:

The CAA requires EPA to provide manufacturers of heavy-duty vehicles, defined as vehicles in 

excess of 6,000 pounds GVWR, (29) with four years of lead time (and a three-year period of 

“stability” with no changes to the standards), to comply with new automobile emission 

standards. Specifically, Section 202(a)(3)(C) of the CAA, 42 U.S.C. § 7521(a)(3)(C), states: 

“Any standard promulgated or revised under this paragraph and applicable to classes or 

categories of heavy-duty vehicles or engines shall apply for a period of no less than 3 model 

years beginning no earlier than the model year commencing 4 years after such revised standard is 

promulgated.” (emphasis added). This statutory requirement is intended to ensure that 

manufacturers of heavy-duty vehicles are afforded sufficient lead time and stability to recoup 

their investments in new technology required to comply with more stringent standards. 

In the proposed rule, EPA attempts to thwart this statutory requirement by proposing two phasein alternatives for complying with the significantly more stringent Tier 3 NMOG+NOx tailpipe 

emissions standards. Under the more favorable primary compliance option, manufacturers must 

meet a fleet average standard that is phased-in between Model Years 2018 and 2025 for vehicles 

over 6,000 pounds GVWR, but which contravenes the CAA’s explicit four-year lead time 

requirement. Under the less favorable alternative compliance option, manufacturers must phase 

in 40 percent of their vehicles to the more stringent Tier 3 NMOG+NOx standards beginning in 

Model Year 2019, which comports with the statutory four-year lead time requirement, but adds 

the significant burden that all of the manufacturer’s vehicles must meet the final standards by 

Model Year 2021 — a full four model years ahead of the primary phase-in option.

Footnote: EPA proposes to adopt a similar dual-path approach for “heavy-duty vehicles” 

as defined by EPA at 40 CFR §86.1803-01 (i.e., vehicles greater than 8,500 pounds 

GVWR but less than or equal to 14,000 pounds GVWR). See 78 Fed. Reg. at 29,875-

29,877. Under the proposed primary compliance option, manufacturers must meet a 

declining fleet average standard for NMOG+NOx beginning in Model Year 2018, in 

contravention of the CAA’s explicit four-year lead time requirement. Alternatively, 

manufacturers can choose to comply beginning in Model Year 2019, which comports 

with the four-year lead time requirement, but then are subject to a percent-of-vehicles 

phase-in approach rather than a declining fleet average. Again, EPA’s “poison pill” 

approach cannot be reconciled with the CAA. Accordingly, Chrysler recommends that 

EPA start the declining fleet average in Model Year 2019, consistent with the CAA’s 

four-year lead time requirement.

Assuming EPA issues a Tier 3 final rule in late 2013, as planned, Model Year 2014 already 

would have begun. Therefore, the CAA requires that the Tier 3 standards applicable to heavyduty vehicles take effect no earlier than Model Year 2019 (i.e. four model years after the revised 

standards are promulgated per Section 202(a)(3)(C), that is, commencing with the 2015 Model 

Year). EPA’s proposed primary compliance option, however, would require manufacturers of 
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heavy-duty vehicles to begin complying with the stringent Tier 3 standards in 2018 (i.e., only 

three model years after the revised standards are promulgated), and therefore would contravene 

the lead time requirement in Section 202(a)(3)(C) of the CAA. Conversely, although EPA’s 

alternative compliance option does meet the statutory four-year lead time requirement, it 

unreasonably imposes unduly and significantly more burdensome compliance requirements than 

the primary compliance option, and does not present manufacturers with a realistic choice. 

Moreover, these undue burdens are not rationally related to the four-year lead time requirement 

and thus are clearly designed as a punitive stick to force manufacturers to “choose” the non-CAA 

compliant primary option with only three years of lead time.

As described in greater detail in the comments provided by the Alliance of Automobile 

Manufacturers and Association of Global Automakers, the alternative compliance option, which 

complies with the four-year lead time requirement but requires manufacturers to certify all of 

their vehicles to the Tier 3 standards a full four model years sooner than the primary phase-in 

option, is so burdensome that no reasonable manufacturer would ever choose it; all 

manufacturers would essentially be forced into selecting the primary phase-in option and turning 

a blind eye to EPA’s blatant violation of the CAA’s lead time requirements for heavy-duty 

vehicles. When a regulatory scheme is so heavily weighted or creates significant economic 

incentives such that only one of the options is reasonable, that option becomes a mandate and is 

no longer truly an option. Providing a significantly more burdensome alternative compliance 

path that meets the statutory requirements does not, and cannot, remedy the fact that the primary 

compliance path violates the statute.

This dual-path approach that EPA proposes would violate the CAA for an additional reason, as 

well. Under Section 202(a)(3)(A)(i) of the CAA, EPA is required to promulgate standards 

“which reflect the greatest degree of emission reduction achievable through the application of 

technology which the Administrator determines will be available for the model year to which 

such standards apply, giving appropriate consideration to cost, energy, and safety factors

associated with the application of such technology”. Thus, the CAA implicitly requires EPA to 

select the single standard that reflects the greatest degree of emission reduction achievable. 

Here, it simply cannot be the case that both the primary compliance option (which begins in 

Model Year 2018 and requires full compliance with the more stringent standards by 2025) and 

the alternative compliance option (which begins in Model Year 2019 and requires full 

compliance with the more stringent standards by 2021) reflect the greatest degree of emission 

reduction achievable taking into account cost, energy, and safety. Rather, if the three-year 

phase-in under the alternative compliance option is in fact achievable considering the specified 

factors, then the primary compliance path, which affords manufacturers seven years to meet the 

more stringent standards, cannot be reconciled with the CAA requirement that EPA promulgate 

standards reflecting the greatest degree of emission reduction achievable. The more likely

explanation, however, is that the primary compliance option reflects the greatest degree of 

emission reduction that EPA believes is truly appropriate, whereas the alternative compliance 

option is intentionally so burdensome—and therefore far beyond reflecting the greatest degree of 

emissions reduction achievable—that manufacturers will be forced to waive their statutory 

protections and choose the primary path. This attempt to circumvent the statutory protections 

embodied in the CAA cannot be reconciled with the plain provisions of the Act.
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Further, Chrysler objects to the requirement that if a manufacturer chooses the alternative 

compliance path for any of its vehicles, all of its vehicles, including light-duty vehicles and those 

heavy-duty vehicles for which the manufacturer is willing to comply with three years lead time, 

must nevertheless meet the final Tier 3 NMOG+NOx standards by 2021 (instead of 2025 under 

the primary compliance option). This regulatory scheme, which sweeps in a manufacturer’s 

entire fleet if the manufacturer chooses to pursue the alternative compliance option for even just 

a single vehicle model, cannot be characterized as an incentive to forego the four-year lead time 

requirement; rather, it is a penalty imposed on manufacturers that refuse to forego their statutory 

protections. There is no rational basis for penalizing a manufacturer’s entire vehicle fleet simply 

because the manufacturer chooses to exercise its statutory right to four years of lead time for one 

heavy-duty vehicle model. Plainly, any emissions benefits of earlier compliance would accrue 

for those models of vehicles for which the manufacturer might choose earlier compliance. But 

precluding that choice and imposing more stringent standards even for those models that might 

comply early, just because a different model or models cannot comply early, has no 

environmental rationale except to penalize the choice of later compliance for the other models. 

That design is arbitrary, unreasonable, and unlawful.

Recommendation: Chrysler recommends that, for vehicles over 6,000 pounds GVWR, the Tier 3 

fleet average requirements for FTP and SFTP NMOG+NOx begin in MY 2019 at the currently 

proposed Model Year 2019 fleet average emissions levels (under the primary compliance option) 

and require full compliance only at Model Year 2025. This approach is in full compliance with 

the CAA, completely harmonizes with LEV III in MY 2019, and will achieve the same level of 

emission reduction as the proposed rule. 

Our Response:

Chrysler commented on Clean Air Act requirements for lead time and stability for 

vehicles over 6000 lbs GVWR. Excerpts from these comments pertaining to vehicles over 8500 

lbs GVWR are addressed here. Those dealing with vehicles 6000-8500 lbs GVWR are 

addressed in Chapter 4.1.1.

Comments we received on the proposed HDV standards did not specifically address our 

analysis of their technical feasibility. The Manufacturers of Emission Controls Association 

(MECA) outlined diesel and gasoline-engine technologies that they expect will be used to 

achieve the Tier 3 standards cost-effectively, generally consistent with our RIA. These 

comments are discussed in Chapter 4.1.4. Vehicle and engine industry commenters argued that 

the case we made for feasibility relied too heavily on extending light-duty truck test data, 

supplemented by testing of only two HDVs, neither of which were fully aged or representative of 

future vehicles designed to meet our new GHG standards. However, these comments did not 

question the feasibility, durability, implementability, or effectiveness of the technologies we 

identified, or their ability to achieve the proposed standards. Instead, the focus of these 

comments was on statutory provisions for lead time and stability, and on how relaxed standards 

for in-use testing and testing at high altitudes would help to implement the standards within the 

allotted lead time. These issues, including changes we are making in response to the comments, 

are addressed in Sections IV.B.2.c, IV.B.6.a, and IV.B.6.f, of the preamble to this final rule. 

Related additional discussion can be found in Chapters 4.2.4 and 4.2.6.1 below.
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Contrary to the assertions of these commenters, HDV manufacturers clearly have a 

choice between the primary LEV III-harmonized phase-in and the alternative percent-of-sales 

phase-in. As discussed in the preambles to the proposed and final rules, we are providing for the 

LEV III-harmonized phase-in to allow manufacturers to more easily market the same HDV 

models in all 50 states. We are also providing for the alternative percent-of-sales phase-in so 

that manufacturers may choose to benefit from four years of lead time and three years of stability 

as specified in CAA section 202(a)(3)(C). That a commenter might view one alternative as 

“more favorable” and the other “less favorable” does not mean that a manufacturer does not have 

a choice of phase-in alternatives under the Tier 3 program. 

As acknowledged by the commenters, the alternative phase-in clearly meets statutory 

lead time and stability requirements, but commenters argue that the alternative phase-in of the 

Tier 3 HDV standards is not technologically feasible. Commenters who disagreed with our 

assessment of the feasibility of the alternative phase-in for HDV manufacturers did not explain 

the reasons for their disagreement, beyond referring to similar comments they had on the 

analogous light-duty (above 6000 lbs GVWR) alternative phase-in. However, the proposed 

light-duty alternative differs from the one we proposed for HDVs, and the elements in it that 

were found objectionable by the manufacturers are not present in the HDV alternative. The 

HDV alternative does not impose “unduly and significantly more burdensome compliance 

requirements than the primary compliance option”, and we see no reason to conclude that it does 

not present manufacturers with a realistic choice.

Commenters objected that the proposed percent-of-sales alternative has not been shown 

by EPA to be feasible, or in fact is infeasible because it mandates the early phase-in of lowemitting vehicles certified to the final standards. In fact, the percent-of-sales phase-in is no more 

stringent than the LEV III-harmonized phase-in, so a manufacturer meeting the percent-of-sales 

alternative would not have any more difficulty meeting the stringency levels than a manufacturer 

using the other approach. EPA chose the phase-in percentages in the percent-of-sales alternative 

to result in a fleet average NMOG+NOx level that is equal to the LEV III-harmonized standards. 

For example, a manufacturer choosing the percent-of-sales approach must demonstrate 

(including through use of credits) that 60% of its MY2019 Class 3 fleet meets the final Tier 3 

NMOG+NOx standard of 247 mg/mi; the remaining 40% may be certified to pre-Tier 3 NMHC 

and NOx standards adding up to 630 mg/mi. On average this Class 3 fleet attains (40%)x(630) + 

(60%)x(247) = 400 mg/mi, which is the fleet average standard in this year under the LEV IIIharmonized alternative.

In response to the comments about EPA’s assessment of feasibility for the percent-ofsales alternative standards, the feasibility analysis provided in the Final RIA, which expressly 

addresses the LEV III-harmonized phase-in, serves to demonstrate the feasibility of both 

alternatives. Contrary to commenters’ contentions, neither alternative mandates the early phasein of low-emitting vehicles certified to the final standards, due to the existence of identical 

averaging, banking, and trading (ABT) provisions in both alternatives. In fact, with ABT, every 

manufacturer can produce the same mix of vehicles in any model year to comply with either 

HDV phase-in alternative, with the exception that MY 2018 is a voluntary phase-in year under 
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the alternative phase-in and a required year under the LEV III-harmonized phase-in. By no 

means are manufacturers forced to make only vehicles certified to the final standards.

Some comments seem to assert that the percent-of-sales construct for the alternative was 

chosen by EPA to make this alternative so stringent (by forcing some vehicles to meet final 

standards four years early) that no reasonable company would use it. This is incorrect, both in 

regard to its actual effect (discussed above), and in regard to our intent. Rather, the percent-ofsales construct for the alternative was proposed and is being adopted to provide manufacturers 

with a phase-in alternative that explicitly meets the applicable Clean Air Act stability 

requirement, consistent with the commenter’s legal statements.

We are making one change to the percent-of-sales alternative, necessitated by the fact 

that this final rule is being signed in 2014, not 2013 as envisioned in the proposal. HDV models 

for which the 2019 model year begins before the fourth anniversary of the signature date of this

final rule may be excluded from the Tier 3 fleet average compliance calculations and all other 

Tier 3 requirements. These excluded vehicles would instead need to comply with the applicable 

pre-Tier 3 standards and requirements for the entire production of these models throughout the 

2019 MY. This limited allowance ensures that the alternative meets EPA’s obligation for four 

years of lead time under the Clean Air Act. It is similar to a phase-in alternative we provided in 

the light-duty vehicle Tier 2 rule (see 65 FR 6747, February 10, 2000).

4.2.2. HDV FTP Exhaust Standards

What Commenters Said:

Truck and Engine Manufacturers Association (EMA):

Chassis-Dynamometer-Certified Heavy-Duty Vehicle NOx Standards: 

The current NOx standards for heavy-duty, chassis-certified vehicles are 0.2 g/mile and 0.4 

g/mile for Class 2b and Class 3 vehicles, respectively. Under the Proposed Tier 3 Standards, 

EPA is proposing two interim bins, one for Class 2b and one for Class 3, both of which are 

intended to be “carry-over bins” for existing Tier 2 vehicles. This would allow manufacturers to 

continue certifying vehicles that are designed to meet the current standards without any 

modifications. However, as proposed, the NOx standards for these “interim bins” are expressed 

as three significant digits (0.200 g/mile and 0.400 g/mile for Class 2b and Class 3, respectively). 

Such a change represents a significant increase in the stringency of the standards due to the 

applicable rounding rules. Having three significant digits (instead of one) means that existing 

vehicles would be subject to significantly more stringent NOx standards, which is not consistent 

with the intent of creating “interim bins.”

EMA believes that this proposed change in significant digits was unintentional on EPA’s part. 

Either way, EPA should not change the number of significant digits for the NOx standard in the 

“interim bins” for chassis dynamometer certified heavy-duty vehicles. Rather, the Agency 

should – indeed, must – retain the NOx standard at 0.2 g/mile and 0.4 g/mile for Class 2b and 
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Class 3 interim bins, respectively. Otherwise, EPA’s proposed standards are inconsistent with its 

expressed intent – which EMA supports – to allow “carryover” bins. 

Chassis-Dynamometer-Certified Heavy-Duty Vehicle PM Standards:

The current PM standard for heavy-duty, chassis-certified vehicles is 0.02 g/mile for both Class 

2b and Class 3 vehicles. Under the Proposed Tier 3 Standards, EPA is proposing two interim 

bins, one for Class 2b and one for Class 3, both of which are intended to be “carry-over bins” for 

existing Tier 2 vehicles. This would allow manufacturers to continue certifying vehicles that are 

designed to meet the current standards without any modifications. However, as proposed (Table 

5 of 86.1816-18), the PM standards for these “interim bins” do not match the values in 86.1816-

08. Instead of 0.02 g/mile, the PM standards for the two bins in each class are listed as 0.012 

g/mile. Such a change represents a significant increase in the stringency of the standard due to 

both the lower value and to the inclusion of three significant digits. The lower numeric value 

and the three significant digits (instead of two) means that existing vehicles would be subject to 

significantly more stringent PM standards, which is not consistent with the intent of creating 

“interim bins.”

EMA believes that this proposed change was unintentional on EPA’s part. Either way, EPA 

should not change the numeric level or the number of significant digits for the PM standard in 

the “interim bins” for chassis dynamometer certified heavy-duty vehicles. Rather, the Agency 

should – indeed, must – retain the PM standards at 0.02 g/mile for both Class 2b and Class 3 

interim bins. Otherwise, EPA’s proposed standards are inconsistent with its expressed intent –

which EMA supports – to allow “carryover” bins. 

[EMA recommends that EPA undertake the following:]

- Correct the number of significant digits in the NOx standards for chassis-certified heavy-duty 

vehicles to maintain the standards at 0.2 g/mi and 0.4 g/mi for Class 2b and Class 3 vehicles, 

respectively 

- Correct the numeric value and the number of significant digits in the PM standard for chassiscertified heavy-duty vehicles to maintain the standard at 0.02 g/mi for Class 2b and Class 3 

vehicles 

Our Response:

We agree with EMA’s comments regarding the numerical levels of the NOx and PM 

standards for the interim bins. We have corrected the PM standard accordingly in the 

regulations. In response to another comment (made by EMA and others—see Chapter 4.2.2.1), 

we have combined the NMOG and NOx standards for these interim bins, with an additional 

requirement capping the NOx level in certification testing. This capped level is specified in the 

regulation with a single significant digit, as suggested by EMA. This, along with the flexibility 

for NOx emissions provided under a combined NMOG+NOx standard, effectively addresses the 

EMA comments regarding NOx.

What Commenters Said:
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California Air Resources Board (CARB):

Medium Duty Vehicle Fleet Average Requirement: Unlike the LEV III program that requires 

manufactures to certify a defined percentage of their medium-duty vehicle’s to increasingly 

stringent emission standards, the proposed Tier 3 program imposes a fleet average emission 

requirement for this class of vehicles. Staff has determined that, while different in structure, the 

LEV III and proposed Tier 3 emission requirements for medium-duty vehicles are identical. 

Accordingly, to provide manufacturers with additional flexibility, CARB will propose an 

identical fleet average option for compliance in the LEV III program. 

Our Response:

We support CARB’s intent to propose an identical declining fleet average standard 

option.

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global Automakers):

The following list areas from the NPRM preamble for which EPA has requested comment on 

exhaust emission related items. This includes comments and recommendations on items that are 

not addressed in our main comment letter.

HDVs (FR29874): [EPA] request[s] comment on the usefulness of creating additional bins 

between Bin 0 and the next lowest bin in each vehicle class, as a means of encouraging clean 

technologies and adding flexibility. We see no need for additional bins beyond the bins needed 

to harmonize with the California program.

HDVs (FR29876): [EPA] request[s] comment on extending the voluntary compliance 

opportunity to the 2015 model year. Extending voluntary compliance to 2015 as proposed by 

EPA provides no meaningful assistance to manufacturers as they transition to Tier 3. Instead, 

EPA should pattern its HDV early credit provisions after those proposed for light-duty.

HDVs (FR29878): EPA requests comment on this proposed optional [PM] phase-in mechanism. 

We support the optional phase-in mechanism. 

Our Response:

We acknowledge the comments from the Alliance and Global Automakers regarding 

additional bins, 2015 voluntary compliance, and the proposed optional PM phase-in mechanism, 

and are not making changes to the associated final Tier 3 program provisions from what we 

proposed. We are finalizing the proposed optional PM phase-in mechanism for which the 

commenters expressed support. See Chapter 4.2.5 of this Summary and Analysis of Comments 

document for further discussion of comments on early credits.
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4.2.2.1. Combined NMOG + NOx Standards for High Bins

What Commenters Said:

Truck and Engine Manufacturers Association (EMA):

Bin Standards: EPA has proposed separate NMOG and NOx standards for the two highest bins 

in both the 8,501-10,000 lbs. GVWR range and the 10,001-14,000 lbs. GVWR range of vehicles 

and engines. EPA states that its proposal is “equivalent” to California’s LEV II program. EPA

also proposes that those “interim Tier 3” bins be available only through model year 2021. (78 

Fed. Reg. at 29875.)

EPA’s proposal is not “equivalent” to the LEV II program nor does it harmonize with California 

for the two highest bins in both the 8,501-10,000 lbs. GVWR range and the 10,001- 14,000 lbs. 

GVWR range of vehicles and engines. Under California’s requirements for the transition from 

LEV II to LEV III standards, manufacturers may choose whether to certify such vehicles and 

engines to separate NMOG and NOx or combined NMOG+NOx standards at the same levels as 

EPA has proposed for the two highest bins in Classes 2b and 3 (395 (LEV) and 340 (ULEV) for 

Class 2b; 630 (LEV) and 570 (ULEV) for Class 3). Moreover, the California LEV III 

regulations allow manufacturers to certify to those combined NMOG+NOx standards for as long 

as manufacturers are able to do so while still meeting the fleet-wide phase-in requirements. 

Manufacturers certifying to those combined standards also will meet combined OBDII 

thresholds as part of certification.

Meanwhile, EPA also is proposing to adopt ARB’s OBDII regulations. Even though ARB’s 

OBDII threshold for NMOG+NOx will be combined, manufacturers certifying products in those 

bins will not be able to certify to a combined standard or OBDII threshold, eliminating the 

possibility of certification to a 50-state vehicle.

EPA should provide manufacturers with the same option to certify to combined NMOG+NOx 

standards for all bins in the 8,501-14,000 lbs. GVWR range and should allow such option 

beyond the 2021 model year. Manufacturers who have done the development and testing 

necessary to certify such vehicles to the ARB combined standards will have done so also with 

the expectation that EPA would align its standards to assure harmonization nationwide. EPA’s 

Proposed Rule would force certification to separate NMOG and NOx standards for those bins 

and undermine manufacturers’ ability to certify a 50-state vehicle. Such a result would be 

contrary to EPA’s stated goal in the Proposed Rule.

Consistent with its intent to align the EPA program with the ARB standards generally, and to 

support harmonization where technically feasible and reasonable, EPA should allow 

manufacturers the option to certify to combined NMOG+NOx standards for the “interim” bins 

for as long as manufacturers are able to do so. 
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Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global Automakers):

HDVs (FR29875): [EPA proposes] that vehicles in the interim bins meet separate NMOG and 

NOX standards, as indicated in Table IV-13, rather than combined NMOG+NOX standards... 

[EPA requests] comment on this issue and the proposed approach to addressing it.

We support combined NMOG+NOx for the interim HDV bins, consistent with the California 

program and all other Tier 3 bins. 

Our Response:

Industry commenters objected to both the proposed sunsetting of the interim bins and the 

proposed separate NOx and NMOG standards for these bins, arguing that they overly restrict 

manufacturer flexibility and work against harmonization with LEV III. However, commenters 

did not address EPA’s concern expressed in the NPRM regarding increased NOx emissions at 

the interim bin levels.

After considering the comments, we believe a modified approach to the interim bins can 

at least partly address the industry concerns regarding harmonization while still precluding 

backsliding on NOx levels. We are finalizing the interim bins with combined NMOG+NOx 

standards as requested by the commenters, but are adopting a restriction on deteriorationadjusted NOx levels in certification testing, to the levels allowed under the current standards in 

40 CFR 86.1816-08. These are 0.2 and 0.4 g/mi for Class 2b and Class 3, respectively. This 

restriction will not apply to vehicles in use, and does not impose a parallel NMOG restriction.

Given our continuing concerns about NOx increases that would be allowed by the combined 

standards at the interim bin levels, we believe that this approach and the associated certification 

burden are reasonable, noting that manufacturers already must obtain NOx test results in 

certifying to an NMOG+NOx standard, and the differing NOx and NMOG deterioration 

mechanisms will likely dictate that they be considered separately in obtaining deteriorated 

NMOG+NOx levels for certification.

We believe that making the interim bins available indefinitely would run counter to their 

limited purpose as an aid to making the transition to Tier 3 emissions levels. Making these bins 

permanent would, we believe, necessitate that they take on other key elements of the Tier 3 

program such as longer useful life, SFTP compliance, and the use of Tier 3 certification fuel.

These requirements in turn would negate the usefulness of these bins in helping to carry over 

some pre-Tier 3 vehicle designs during the transition years in which the declining fleet average 

standard levels are high enough to accommodate their continued sale. By MY 2022, the fleetwide standard will be stringent enough to effectively eliminate the ability of manufacturers to use 

interim bins while meeting the declining fleet average standard levels. We are therefore 

adopting the sunsetting of the interim bins as proposed, making them available only through MY 

2021.

4.2.3. HDV SFTP Exhaust Standards
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What Commenters Said:

California Air Resources Board (CARB):

Linking of Medium-Duty Vehicle FTP and SFTP Emission Standards: CARB supports the 

proposal to require medium-duty vehicles certifying to a Tier 3 ultralow- emission vehicle or 

super-ultra-low-emission vehicle FTP-equivalent emission category to certify to the equivalent 

SFTP emission category as well. CARB believes this requirement is appropriate because the 

SFTP emission standards were designed to be met using the same hardware required to meet the 

FTP emission standards. Accordingly, CARB intends to propose alignment with this proposal 

once the Tier 3 program is finalized. 

International Council on Clean Transportation (ICCT):

ICCT fully supports extending the supplemental FTP requirements to complete vehicles between 

8,500 and 14,000, which were previously exempt. 

Our Response:

We support CARB’s intent to propose alignment with our requirement linking SFTP and 

FTP compliance.

4.2.4. HDV In-Use Standards

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global Automakers):

Interim In-Use Standards: For the > 8,500 pounds GVWR vehicles and for the SFTP standards 

for LDVs, the proposed Tier 3 regulations do not contain the interim in-use standards that were 

adopted in LEV III. Interim in-use standards do not change the certification value, and therefore 

should not have any environmental impacts. However, manufacturers must certify much bigger 

vehicles to much lower standards across the board at the same time they’re introducing new 

GHG reduction technologies. For example, HDVs 8,500 – 10,000 pounds GVWR currently 

meet standards in the range of 340 mg/mile NMOG+NOx, but vehicles will need to meet 

standards that are half that as Tier 3 and LEV III phase in. The same is true for vehicles 10,000 

– 14,000 pounds GVWR where the standards are currently about 560 mg/mile but will have to 

meet standards almost half that under Tier 3. While these standards appear numerically higher 

than the LDV standards, they are comparable in terms of stringency and emission control 

hardware required given that they apply to larger vehicles that are tested under much heavier 

loads including at adjusted loaded weight (ALW) instead of loaded vehicle weight (LVW).
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The manufacturers do not have extensive in-use experience at these levels for these larger 

vehicles and could face substantial jeopardy as the standards are adopted across a large segment 

of their fleet. Interim in-use standards, which have historically been granted, simply reduce this 

jeopardy and allow manufacturers to gain in-use data and experience with new, more stringent 

requirements.

Similarly, interim in-use standards are appropriate for SFTP for both the MDV and LDV classes. 

For the first time ever, the SFTP standards will apply at a 150,000 mile useful life. And the 

required levels will be far lower than current standard levels. These two factors, coupled with 

the rapid introduction of new technologies driven by the GHG and fuel economy requirements, 

justify the need for interim in-use SFTP standards to help manufacturers manage their in-use 

compliance risk.

Recommendation: We recommend EPA continue the historic practice of allowing interim in-use 

standards by harmonizing with the LEV III interim in-use standards for the HDV FTP and SFTP 

requirements and the LDV SFTP requirements. 

Heavy Duty Vehicle FTP, SFTP, Altitude and PM Interim In-use Standards:

We propose that EPA align with the CA LEV III program by adopting the same interim in-use 

provisions for the FTP, SFTP and PM that are provided in LEV III. These interim standards are 

necessary to mitigate the risks (both known and unknown) as manufacturers phase in to the new 

lower standards, a task which is complicated by: (1) rollout of new GHG-enabling engine 

technologies; (2) first-time application of SFTP standards to HDVs; (3) new test cycle (LA-92); 

(4) new PM test procedures (Part 1066); and (5) differences between federal and CA market fuel 

quality (i.e., sulfur).

In support of its decision to exclude the LEV III interim in-use provisions from the Tier 3 

program, EPA used data generated from only two vehicles. These vehicles were not aged to 

150,000 mile full useful life, and were not representative of the vehicles that will be needed to 

meet new stringent HDV GHG standards. EPA also referenced vehicle data taken from the 

existing light-duty fleet to support the view that interim standards were not needed. The selected 

vehicles had powertrains similar to their heavy-duty counterparts; however, these LDVs were not 

run at adjusted loaded vehicle weight (ALVW) and cannot be properly used to make this 

determination.

Recommendation: We recommend: (1) Harmonizing with LEV III by adopting the interim in-use 

standards for vehicles >6,000 pounds GVWR for both FTP and SFTP. 

California Air Resources Board (CARB):

SFTP Medium-Duty Vehicle Interim In-Use Emission Standards: CARB supports U.S. EPA’s 

proposal to not include interim in-use emission standards for NMOG+NOx and PM in the 

medium-duty vehicle SFTP program. CARB agrees that the technologies required for SFTP 

compliance are well-established and sufficient lead time is provided such that in-use interim 

emission standards, which are typically reserved for new technologies are not needed. 
Tier 3 Summary and Analysis of Comments

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Accordingly, CARB intends to propose alignment with this proposal once the Tier 3 program is 

finalized. 

Ford Motor Company (Ford):

HDV Interim In-Use Standards: In the Tier 3 NPRM, EPA did not adopt the LEV III interim inuse provisions for vehicles in the 8,500-14,000 pound weight classes. Ford believes that EPA’s 

reluctance to harmonize with this aspect of the LEV III program is due, at least in part, to a lack 

of data supporting the need for such provisions. Interim standards are typically intended to 

provide a temporary mechanism for manufacturers to handle the known challenges and 

unforeseen difficulties associated with the implementation of new, more stringent requirements. 

Since manufacturers cannot be expected to supply data to substantiate all such future concerns 

(the relevant vehicles and/or technologies often do not yet exist or have not yet been realized in 

“hardware”), we believe that there is sufficient uncertainty in the proposed HDV program alone 

to justify the adoption of the interim standards finalized in the LEV III program. These 

uncertainties include an entirely new testing mode for heavy-duty vehicles (i.e. SFTP), new 

application of LA-92 test cycle, and the roll-out of new test procedures in Part 1066. These 

concerns are further intensified by the need to implement the new, innovative technologies and 

vehicle configurations that will be required to meet the challenging GHG standards in this same 

timeframe. It should also be noted that the case for interim standards is particularly strong in 

regards to PM, not only because of the unique PM challenges for heavier vehicles detailed in the 

preceding section, but also because EPA has proposed a new PM test procedure in Part 1066.

Recommendation: Ford proposes that EPA adopt the FTP and SFTP interim in-use standards 

(including PM) that were finalized in California’s LEV III MDV program.

General Motors LLC (GM):

Another important area for harmonization relates to in-use compliance. In-use compliance is the

biggest technical hurdle for manufacturers, and also the greatest risk to manufacturers due to all 

of the factors that can impact in-use emission testing results. To help manage this in-use 

compliance risk during the transitional years, the LEV III regulations provide interim in-use 

standards. The Tier 3 regulations adopt some but not all of the LEV III interim in-use standards, 

and as detailed in the Alliance/Global comments, GM requests that EPA adopt all the types of 

interim in-use standards adopted in LEV III to ensure harmonization. 

Truck and Engine Manufacturers Association (EMA):

Interim In-Use Standards: For vehicles above 8,500 lbs. GVWR, the Proposed Tier 3 Standards 

do not include the interim in-use standards that were adopted in the ARB LEV III program. EPA 

should continue the historic practice of allowing interim in-use standards by harmonizing with 

the LEV III interim in-use standards for the Heavy-Duty Vehicle FTP and SFTP requirements.

The interim standards are necessary to address challenges (both known and unknown) that 

manufacturers will face as they phase products in to the new, more-stringent Tier 3 standards. 

As manufacturers design, research, test, and produce Tier 3-compliant vehicles and engines that 
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are commercially viable for introduction into the market, manufacturers also must address the 

following challenges: (1) rollout of new GHG-enabling engine technologies; (2) the first-time 

application of SFTP standards to Heavy-Duty Vehicles (and at 150,000-mile useful life); (3) a 

new test cycle (LA-92); (4) new PM test procedures; and (5) differences between federal and 

California market fuel quality (i.e., sulfur). Without interim in-use standards, manufacturers face 

greater risk that they will not be able to produce fully-compliant vehicles and engines or meet 

customer demands for robust and reliable product.

The Proposed Rule would require manufacturers to certify much larger vehicles to much lower 

standards across the board at the same time they are introducing new GHG reduction 

technologies. For example, Heavy-Duty Vehicles 8,501-10,000 lbs. GVWR currently meet 

standards in the range of 340 mg/mile NMOG+NOx, but such vehicles will need to meet 

standards that are half that as Tier 3 and LEV III phase in. The same is true for vehicles 10,001–

14,000 lbs. GVWR, where the standards currently are about 560 mg/mile but will be reduced to 

half that under Tier 3.

EPA has failed to demonstrate that its proposal to exclude interim in-use standards for HeavyDuty Vehicles above 8,500 lbs. GVWR is technologically feasible. In support of its proposal to 

exclude the LEV III interim in-use provisions from the Tier 3 program for vehicles over 8,500 

lbs. GVWR, EPA used data generated from only two medium-duty vehicles which were not aged 

to 150,000 miles full useful life and were not representative of the vehicles that will be needed to 

meet new, stringent GHG standards for heavy-duty vehicles. In addition, EPA referred to lightduty vehicles with powertrains similar to their heavy-duty counterparts as support for the lack of 

interim in-use standards. Yet, as discussed above, in apparently relying on such light-duty data, 

EPA did not account for the additional technical challenges associated with meeting the 

proposed standards for vehicles and engines over 8,500 lbs. GVWR at ALVW.

Heavy-Duty Vehicles are designed to do work. Manufacturers must design engines used in such 

“work-capable” vehicles with characteristics that allow the vehicle to do the work of hauling or 

towing when such work is required. The design aspects of work vehicles impose laws of physics 

and thermodynamics which result in work-capable vehicles having different emission 

characteristics than light-duty vehicles. As a result, heavy-duty vehicles must be compliant 

under much heavier loads than their light-duty counterparts. Light-duty vehicles cannot and 

should not be relied on for demonstrating the technological feasibility of standards applied to 

heavier vehicles at ALVW. As a result, EPA has failed to show that excluding interim in-use 

standards is technologically feasible for manufacturers.

Manufacturers do not have extensive in-use compliance experience at the proposed standard 

levels for larger, heavier-duty vehicles and could face significant challenges. Any time there is a 

substantial change in regulatory requirements, as standards are adopted across a large segment of 

their fleets, manufacturers not only must meet compliance obstacles but also address customer 

concerns as new products and new technologies are introduced into the market. Interim in-use 

standards, which have historically been allowed, reduce the potential compliance risks and 

impediments to customer acceptance and permit manufacturers to use in-use data and experience 

with the new, more stringent requirements to make any adjustments necessary to assure 

compliance with the fully-implemented final standards. 
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In order to make its program practical and implementable, EPA should align with the California 

LEV III program by adopting the same interim in-use provisions for the FTP, SFTP and PM 

standards as are provided in LEV III.

- Include interim in-use FTP, SFTP, and SFTP PM standards for vehicles above 8,500 lbs. 

GVWR 

Our Response:

After considering the comments we have concluded that relaxed interim in-use standards 

are appropriate for HDVs, both for FTP and SFTP testing. The comments we received from 

CARB, offered in the spirit of fostering harmonization, do not provide new technical information 

in support of going forward with our proposal not to set interim in-use standards. We are 

adopting HDV in-use standards levels that are identical to those adopted for LEV III. We 

consider these levels reasonable, in line with relaxed in-use standards adopted in past programs, 

and helpful toward harmonization.

We are not applying interim in-use NMOG+NOx standards to the interim (two highest) 

bins for the FTP standards, because these bins are intended for carry-over of existing designs, 

and there should be little uncertainty over their in-use emissions performance. Interim bin 

vehicles certified to the Tier 3 PM standards shall, however, be subject to the relaxed in-use PM 

standards in the same way as for HDVs in other bins. Bin 0 standards are driven by specific 

zero-emissions technologies for which in-use margins would not be appropriate, and so we are 

not setting in-use standards for Bin 0. We are also adopting the general approach taken in LEV 

III of making these interim standards available during the phase-in period (model years 2016-

2022) for the first two model years that a test group is newly certified to a Tier 3 NMOG+NOx 

or PM standard.

4.2.5. HDV Emissions Averaging, Banking, and Trading Program

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global Automakers):

Early Opt-in vs. Early Credits:

Historically, agencies have provided a mechanism to earn early credits in order to facilitate the 

transition into more stringent fleet average requirements and to safeguard against unforeseen 

circumstances that could cause a deficit situation. Although the proposed HDV program allows 

manufactures to opt-in to the program early, this is not equivalent to providing early credits. The 

early opt-in option is also more stringent than the LEV III program, which will allow for 

carryover of LEV II credits into the LEV III phase-in. Given the short lead time, extending this 

opt-in period to the MY 2015 would not provide significant additional flexibility to 

manufacturers.
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Recommendation: We propose that EPA align the HDV credit provisions with the light-duty 

program by allowing early credits to be generated in MYs 2016 and 2017 vs. a Bin 395/630 

average. National HDV credits could then be proportionally capped at the CA level in MY 2018. 

VEC vs. Fleet average:

EPA is proposing a fleet-average based compliance for HDVs. This is different than ARB’s 

approach in LEV III, which uses Vehicle Equivalent Credits (VEC) to determine compliance. 

Adoption of these incongruent approaches for compliance demonstration and reporting would 

prevent the harmonization of LEV III and Tier 3 for HDVs, even though the stringency of the 

EPA and California standards are equivalent. Since the stringency is equivalent, manufacturers 

have no preference for the method. ARB staff have indicated that ARB would consider allowing 

optional compliance with the EPA fleet average. Although this would have the effect of 

harmonizing the requirements, ARB is not currently in rulemaking and cannot consider 

providing this option until after EPA finalizes Tier 3.

Recommendation: Since EPA is in rulemaking, we recommend that EPA provide an option for 

manufacturers to comply using California’s VEC system. After EPA finalizes Tier 3 and ARB 

adopts the optional compliance with the fleet average approach in Tier 3 (assuming ARB does 

so), manufacturers would not object to EPA eliminating the California VEC option. 

Our Response:

Industry commenters argued that EPA should align the HDV credit provisions with the 

light-duty program by allowing early Tier 3 credits to be generated in MYs 2016 and 2017, 

calculated relative to the highest Class 2b and Class 3 bin NMOG+NOx levels (395 and 630 

mg/mi, respectively), and capped at a level proportional to the California level in MY 2018.

However, these highest bin levels correspond to those of the existing HDV standards for NMHC 

and NOx, and are significantly higher than the MY 2016 and 2017 LEV III levels. Thus vehicles 

designed to just meet the LEV III standards in these years could generate a large preliminary 

number of credits under the industry’s Tier 3 early credits proposal, credits they would not earn 

in LEV III, thereby potentially thwarting the harmonization of the two programs, undermining 

the stringency and benefits of Tier 3, and bringing into question whether the standards should be 

revised to meet the requirements of Clean Air Act section 202(a)(3)(A).

We considered whether truncating that credit bank for each manufacturer in 2018 such 

that it is proportional to their LEV III balance, combined with additional restrictions on trading 

and banking, would address these concerns and restore a harmonized credit status in that year.

However, such an approach would constitute an unnecessarily complex and uncertain pathway to 

the same result as that achieved under EPA’s early opt-in provisions. We are also not we 

providing for the conversion of pre-Tier 3 HDV credits for use in Tier 3, as we believe that by 

providing an early Tier 3 opt-in program for HDVs, capable of generating credits for two model 

years before the mandatory standards take effect (even longer under the alternative percent-ofsales phase-in approach), we are giving ample opportunity for the manufacturers to accumulate 

early credits. HDV manufacturers are currently certifying their vehicles to existing standards 

without generating or using NOx or NMHC credits, and the levels we set for Tier 3 standards are 
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not based on any assumption of credit transfers into Tier 3. Allowing such transfers would also 

introduce new complexities in dealing with the conversion of NOx and NMHC credits into 

NMOG+NOx credits.

Manufacturers commented that the proposed fleet average compliance approach is 

incongruous with California’s LEV III method based on vehicle equivalent credits (VECs).

Although stating that they do not have a preference for the method (since the stringency is 

equivalent), they recommended that EPA foster harmonization by providing a compliance option 

based on VECs. We believe that such an option would add unnecessary complexity to the Tier 3 

program, and is made even more unnecessary by the intent expressed in CARB’s written 

comments to propose a fleet average option for LEV III that is identical to EPA’s approach.

4.2.6. Other HDV Provisions

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global Automakers):

Chassis vs. Dyno Cert:

We request that EPA align with LEV III and allow the option to choose chassis or dyno 

certification for complete diesel engines 10,000-14,000 lbs. GVWR (Class 3). Without this 

option, manufacturer’s may be required to dual certify vehicle models that include variants both 

under and over 14,000 pounds. 

International Council on Clean Transportation (ICCT):

The ICCT supports maintaining fuel-neutral criteria emissions standards for heavy-duty vehicles. 

We also fully support extending chassis-based emission requirements to all complete vehicles up 

to 14,000 gross vehicle weight. 

It is ICCT’s position that technology-neutral performance standards are critical in any 

transportation policy, especially one that involves multiple and alternative fuels that can all be 

utilized as part of meeting emissions and energy objectives. Thus, we are supportive of 

maintaining fuel neutral criteria emissions standards for heavy-duty vehicles.

The ICCT fully supports extending chassis-based emission requirements to all complete vehicles 

up to 14,000 gross vehicle weight. The trend since the first standards were adopted in the 1970s 

has been to increase the GVW of pickup and other light trucks above the threshold for light-duty 

emission standards. This has especially been a problem for diesel engines in pickup trucks, 

which are only sold above 8,500 GVW in order to avoid the light-duty emission standards. 

Extending the threshold to 14,000 GVW will ensure emission standards are applied appropriately 

to all complete vehicles. 

Truck and Engine Manufacturers Association (EMA):
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Chassis- and Engine-Dynamometer Certification of Complete Vehicles:

EPA has proposed to “codify” the practice of most, if not all, manufacturers that currently 

chassis-certify their Heavy-Duty Vehicles by requiring all diesel-fueled complete vehicles to be 

chassis-certified under the Proposed Rule. Furthermore, although incomplete Heavy-Duty 

Vehicles are not required to be chassis-certified, EPA has requested comment on requiring 

chassis certification of Class 2 incomplete vehicles as is required under the California Air 

Resources Board’s (“ARB”) LEV III program for vehicles up to 10,000 lbs. GVWR.

EMA and its members oppose mandatory chassis-certification for any class of engines or 

vehicles over 8,500 lbs. GVWR. Even if manufacturers have more frequently chosen to certify 

such vehicles on the chassis test, EPA should not remove the flexibility manufacturers currently 

have with respect to certification of diesel-fueled complete vehicles. Rather, EPA should 

finalize a rule that allows engine manufacturers the continued option to choose either chassisdynamometer or engine-dynamometer certification for both complete and incomplete 

engines/vehicles over 8,500 lbs. GVWR. Maintaining the option allows manufacturers 

continued flexibility in certification decisions, thereby minimizing unnecessary costs and 

certification burdens.

EMA recognizes that its recommendation for optional chassis-certification for complete vehicles 

is one area where we are not recommending harmonization with ARB, which mandates chassisdynamometer certification for complete vehicles with GVWRs between 8,501 and 10,000 lbs. 

GVWR. Such lack of harmonization in this area is appropriate, however, as it provides 

manufacturers greater compliance flexibility without adverse emissions impact.

If EPA nevertheless proceeds with mandatory chassis-certification, EPA, at a minimum, should 

align with ARB’s LEV III Rule and allow manufacturers the option of engine or chassis 

dynamometer certification for complete vehicles with GVWRs between 10,001 and 14,000 lbs. 

or the engines used in them. 

- Allow engine manufacturers the continued option to choose either chassis dynamometer or 

engine-dynamometer certification for both complete and incomplete vehicles between 8,501 lbs. 

and 14,000 lbs. GVWR.

- Adopt the recommended high-altitude standards for heavy-duty vehicles.

- Engage in further review of optional chassis- or engine-dynamometer certification for gasolineor diesel-fueled vehicles over 14,000 lbs. GVWR. 

Our Response:

Industry commenters opposed mandatory chassis certification for complete diesel 

vehicles, especially for vehicles in Class 3. ICCT supported it. It is difficult to assess the degree 

to which a desire to avoid light-duty regulations has driven a shift in the diesel market toward 

heavy-duty pickups as asserted by ICCT. Nevertheless, although sensitive to the issues raised by 

the manufacturers, we remain concerned that the fleet average standard program we are 

finalizing would not work well if a major fleet component, such as complete Class 3 diesel 

trucks, can be left in or taken out of the fleet calculation based on what each manufacturer 
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considers to be most advantageous. We believe the resulting competitive issues and 

uncertainties would be problematic, given the wide variance in gasoline/diesel HDV sales among 

the manufacturers, our provision for averaging across each manufacturer’s entire Class 2b/3 

fleet, and the overwhelming preponderance of diesels in the Class 3 market. It would also create 

uncertainties in the Tier 3 environmental benefits, given the pronounced difference between 

these Tier 3 standards and the heavy-duty diesel engine standards we set 13 years ago, which we 

expect to remain in effect for the foreseeable future.

As a result, we are finalizing the proposed requirement for chassis certification of 

complete (but not incomplete) diesel Class 2b/Class 3 HDVs, except that we are providing that 

manufacturers of complete diesel Class 3 HDVs may, instead of certifying these vehicles, install 

diesel engines that are engine-certified in any model year that the engine family has less than half 

of its sales being installed in such complete Class 3 vehicles. This provision is intended to help 

address manufacturers’ concern about dual certification, while at the same time ensuring a 

coherent fleetwide standards regimen in this vehicle class. It also better harmonizes with 

California’s LEV III program which does not mandate chassis certification for diesel Class 3 

vehicles. By only allowing for engine-certified vehicles when they use engines primarily 

produced for other purposes, we believe this approach adequately guards against potential 

abuse. In the case of complete diesel Class 3 HDVs produced by a company other than the 

engine certifier, the responsibility for ensuring the sales limit is not exceeded remains with the 

vehicle manufacturer, who will need to coordinate with the engine supplier.

4.2.6.1. High Altitude Standards

What Commenters Said:

Truck and Engine Manufacturers Association (EMA):

High-Altitude Standards:

EPA requires high-altitude testing for Heavy-Duty Vehicles (8,501-14,000 lbs. GVWR). While 

EPA provides high-altitude testing relief in the Tier 3 Rule (relative to low-altitude standards) for 

light-duty vehicles, EPA does not provide similar relief for Heavy-Duty Vehicles. (78 Fed. Reg. 

29870, Table IV-9.) Separate high-altitude standards such as those provided in the light-duty 

Tier 3 program also are needed for HDVs, which must test at ALVW even at high altitude. 

EMA recommends that EPA adopt separate high-altitude standards for Heavy-Duty Vehicles in

the same proportion as it provides for LDVs. The table below (marked “Table IV- 13B” to 

indicate its proposed placement in the Preamble) [The table can be found on p. 8 of Docket 

number EPA-HQ-OAR-2011-0135-4314-A1] shows the high-altitude FTP Standards 

recommended by EMA. Consistent with the proposed relief for light-duty vehicles, no 

adjustment is made for the interim bins.

EMA has recommended high-altitude standards for Class 2b Bin 250 and for Class 3 Bin 400 

that are higher than the high-altitude standard for Class 2b Bin 340 and for Class 3 bin 570, 

respectively. The explanation for this apparent anomaly is that the useful life for the non-interim 
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bins is higher (150,000 miles) than it is for the interim bins (120,000 miles), thus requiring 

higher standards for the immediately lower bins.

Ford Motor Company (Ford):

HDV High-Altitude Provisions:

In the proposed rule, EPA acknowledged that fundamental physical challenges exist at high 

altitude that typically results in higher emissions during cold starts. EPA accordingly proposed 

altitude relief, but only for light-duty vehicles. Heavy duty vehicles have similar, if not greater, 

challenges at high altitude. These vehicles are designed to operate under load and trailer tow 

conditions, and as a result the emissions systems are located further downstream from the 

exhaust manifold relative to a light duty vehicle, further delaying catalyst light-off. To provide 

manufacturers with sufficient compliance margin, we propose that EPA provide altitude relief 

for the most stringent HDV bins.

Ford proposes that EPA also provide the following high-altitude standards for HDVs:

[Specific proposed high-altitude standards for HDVs follow.] 

 

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global Automakers):

Separate altitude standards such as those provided in the light-duty Tier 3 program are also 

needed for HDVs, which must test at ALVW even at high altitude.

We recommend: Adopting separate high-altitude standards for vehicles >6,000 pounds GVWR 

in the same proportion as LDV. 

Our Response:

Manufacturers argued in their comments that the reasons EPA cited in proposing relief at 

high altitudes for light-duty vehicles apply for HDVs as well, and requested that relaxed 

NMOG+NOx standards be adopted in the more stringent bins for testing of HDVs at high 

altitudes. Ford argued that the challenges could be even greater for HDVs because they are 

designed to operate at high altitudes with heavy payloads and towed trailers, and this may 

necessitate the locating of emissions systems farther from exhaust manifolds, thereby increasing 

catalyst lightoff delays.

Although we agree to a certain extent about the performance of gasoline-fueled HDVs at 

high altitudes and their similarity to LDVs, the comments did not alter our view that the 

compliance margins provided in the HDV FTP bin standards compared to what the control 

technologies can achieve, and the freedom manufacturers have to shift to the more stringent bins 

gradually as the program phases in, are adequate to account for these effects at altitude. The 

manufacturers provided no data to counter this view.

We note that our adoption of relaxed interim in-use standards for vehicles in these bins 

will be directionally helpful to address any remaining concerns by manufacturers regarding 
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emissions at altitude (preamble Section IV.B.6.a). This is because testing at high altitudes is 

often not required for certification (typically manufacturers use an engineering analysis instead), 

and thus the relaxed in-use standards will help to facilitate Tier 3 implementation for any HDV 

designs in which in-use problems at high altitudes surface in the initial model years.

4.2.6.2. Vehicles Over 14,000 Lbs.

What Commenters Said:

Truck and Engine Manufacturers Association (EMA):

Optional Certification for Vehicles Over 14,000 Pounds GVWR:

Currently, heavy-duty gasoline vehicles (HDGVs) above 14,000 lbs. GVWR (or the engines 

used in them) have the option of certifying on either an engine dynamometer or chassis 

dynamometer to demonstrate compliance with GHG requirements. As EPA notes in the 

Preamble, manufacturers choosing the chassis dynamometer option to certify a family of 

HDGVs for GHGs must use the engine dynamometer test to certify to g/hp-hr standards for all 

other emissions. (78 Fed. Reg. at 29883.) EPA requests comment on extending this HDGV 

option for the demonstration of compliance with criteria pollutant requirements.

In addition, heavy-duty diesel vehicles (HDDVs) above 14,000 lbs GVWR (or the engines used 

in them) currently must certify on an engine dynamometer to demonstrate compliance for both 

criteria pollutant and GHG requirements. EPA requests comment on whether to provide the 

option to certify on either an engine dynamometer or chassis dynamometer to demonstrate 

compliance with criteria pollutant and GHG requirements to HDDVs (or the engines used in 

them).

While EMA generally supports compliance options that provide flexibility to manufacturers in 

meeting regulatory requirements, there are still significant unknowns regarding EPA’s intent in 

possibly offering the options. EMA recommends that EPA engage heavy-duty engine and 

vehicle manufacturers in a thorough review of the issues and their potential impacts. That has

not yet been done. In addition, we will continue to review EPA’s request for comment and will 

strive to provide EPA supplemental comments. 

Cummins Inc.:

Optional Chassis Certification for Vehicles above 14,000 Pounds GVWR:

The existing heavy-duty greenhouse gas (GHG) regulations allow manufacturers to certify 

heavy-duty gasoline vehicles (both complete and cab-complete) on either the engine 

dynamometer or chassis dynamometer to demonstrate compliance with GHG requirements. 

However such vehicles must be certified on an engine dynamometer for all other emissions 

standards (g/hp-hr). EPA requests comment on allowing a manufacturer to certify a heavy-duty 

gasoline vehicle (HDGV) for all emissions standards using chassis dynamometer procedures. 
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In addition, engines for heavy-duty diesel vehicles (HDDVs) above 14,000 lbs GVWR currently 

must certify on an engine dynamometer to demonstrate compliance for both criteria pollutant and 

GHG requirements. EPA requests comment on whether to provide the option to certify on either 

the engine dynamometer or chassis dynamometer to demonstrate compliance with criteria 

pollutant and GHG requirements for engines for HDDVs. 

Cummins does not support an option of chassis certification for GHG or criteria emission 

standards for vehicles above 14,000 lbs GVWR. Cummins urges EPA not to finalize these 

options.

In the NPRM, EPA has not provided any regulatory language or discussed this option in detail in 

the Preamble. It is not clear how such an option would work and what the limits are relative to 

vehicle size. For example, EPA has not specified whether such an option would be limited to 

Class 4 vehicles only or if it would extend to even bigger vehicles. In absence of such details, it 

is impossible for Cummins or any entity for that matter to consider the implications of these 

provisions.

For vehicles above 14,000 lbs GVWR, EPA already has a robust regulatory framework for both 

GHG and criteria emissions based on engine dynamometer test procedures. The engine 

dynamometer test cycles (e.g. FTP) are appropriate for such vehicles, and EPA would need to 

study the applicability of chassis dynamometer test cycles if the Agency wants to move forward 

with consideration of these options.

Under the current GHG rule, HDGVs above 14,000 lbs can certify to chassis standards based on 

a ‘complete sister vehicle’ concept. Vehicles above 14,000 lbs (e.g. Class 4-6 vehicles) are 

typically engineered and marketed to meet vocational requirements. Many of the vehicles in this 

class are not sold as complete, ready to be placed into service, vehicles. The common sales path 

to the end-user is through a specialty body or utility function builder. While the vehicle OEM 

can communicate parameters such as aerodynamic design standards to which the finish builders 

must comply, the finish body may exceed the frontal projection and/or may affect air flow quite 

differently than on a complete pickup truck or even on the bare “cab-complete” vehicle. Hence 

it may not be appropriate to use coastdown and test weight information of a complete sister 

vehicle (in Class 2b/3) for chassis certification of vehicles above 14,000 lbs GVWR.

EPA also requested comments on whether manufacturers of such vehicles that are certified to a 

Final Tier 3 bin should be allowed to exclude them from the fleet average NMOG+NOX 

calculation. Cummins does not support this provision. Excluding these vehicles from fleet 

average calculations could potentially lead to unintended consequences. For example, a 

manufacturer could increase GVWR of their heavier Class 3 vehicles to just above the threshold 

(e.g., 14,001 lbs GVWR) and then exclude them from fleet average calculations.

Recommendation: Cummins urges EPA not to finalize these proposed options for chassis 

certification for vehicles above 14,000 lbs GVWR or exclusion of these vehicles from fleet 

averaging. If EPA wants to consider these options, Cummins would work with the Agency and 

other heavy-duty engine and vehicle manufacturers to engage in a complete review of the issues 

and potential impacts of such a rule.
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Our Response:

Cummins and EMA responded to our request for comment on optionally extending 

chassis-based certification to vehicles over 14,000 lbs. Both commenters felt that a more 

thorough review of the issues and potential impacts involved needs to occur before EPA takes 

action on this matter. We agree and are not making this change in this rule.

4.3. Evaporative and Refueling Emission Standard Comments

See 78 FR 29884-29899, May 21, 2013 for full detail on the proposal

4.3.1. Tier 3 Evaporative Emission Standards

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Evaporative Emissions 2017 Phase in Requirement:

The Tier 3, LEV III, and PZEV zero evaporative emissions standards are identical. The phase-in 

is also identical in all but MY 2017. For MY 2017, California does not require a specific 

percentage of a manufacturer’s fleet meet the LEV III evaporative emissions standards. Instead, 

MY 2017 vehicles in California that generate PZEV credits are required to certify to the zero 

evaporative emission standard. The proposed Tier 3 regulations allow two options for 

compliance in MY 2017. The first option requires a manufacturer to meet the Tier 3 evaporative 

emissions standard on 40 percent of its fleet less than 6,000 pounds GVWR. The second option 

requires the manufacturer to make the PZEV evap systems available nationwide (i.e., for all 

California PZEVs, the evaporative emissions control system would need to be sold nationwide). 

The Tier 3, LEV III, and PZEV evaporative emissions standards require manufacturers to make 

significant hardware changes to the vehicle. These hardware changes trickle down throughout 

the manufacturers’ development, testing, certification, and supply chain and require substantial 

lead time to avoid very costly disruptions. While the Tier 3 proposal would have provided 

sufficient lead time had Tier 3 been finalized in late 2011 (i.e., the 2012 MY), meeting those 

same requirements when manufacturers have lost two years of lead time would be very costly 

and disruptive. In addition to the early leak emission standard option described above, the option 

to make PZEVs available nationwide isn’t necessarily as clear as it could be. We understand that 

this option would require that if a manufacturer made a single vehicle model with three option 

packages (4-cylinder, 6-cylinder, and hybrid) but only the hybrid was a PZEV, then the 

manufacturer would need to make the evaporative system on the hybrid available nationwide. 

The manufacturer would not have to meet Tier 3 evap (or PZEV evap) on the 4-cylinder and 6-

cylinder vehicles nor restrict sales of those vehicles. However, the regulatory requirements in 

§86-1813-17 could be read to require the manufacturer to produce Tier 3 evap in all three 

vehicles, which we understand is not EPA’s intent. Furthermore, we believe EPA’s ultimate 

intent with this provision is that manufacturers choosing this option produce about the same

proportion of zero evaporative emission vehicles in the non-Section 177 states as they produce in 
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the Section 177 states without being subject to sales mix differences between the two regions 

which are beyond the manufacturer’s control. We recommend language below to clarify this 

option.

We recommend revising §86-1813-17(g)(3) as follows:

(3) You may disregard the percentage phase-in specified in paragraph (a)(5) of this section for 

2017 if you choose 50-state certification for all your vehicles meeting the LEV III PZEV 

evaporative standards in 2017. Under this option, you may not produce a higher-emitting version 

of those vehicle models for sale outside of California or the section 177 states. For example, if a 

manufacturer produces Model X in four configurations (4-cylinder (50-State non-PZEV), 6-

cylinder (50-State non-PZEV), hybrid (CA PZEV), and hybrid (Federal, non-PZEV), then you 

could comply with the 2017 model year requirement by putting the CA-PZEV evap system on 

the hybrid (Federal, non-PZEV) vehicle; you would not have to make changes to the 4-cylinder 

or 6-cylinder vehicles. Such vehicles may be certified using carryover data under the California 

program; however, they may generate or use emission credits only if they are certified to meet 

the emission standards of paragraph (a)(2) of this section. Vehicles that comply under this 

paragraph (g)(3) may not generate allowances under paragraph (g)(1) of this section, regardless 

of the calculated percentage of compliant vehicles in model year 2017. Furthermore, you will be

deemed in compliance if the fraction of 2017 MY vehicles with LEV III PZEV evaporative 

systems sold in the non-Section 177 states is within three percent of the fraction of 2017 MY 

vehicles you sold in California.’

Our Response:

This option was proposed to permit the manufacturers to simply extend their current 

SULEV or PZEV Zero Evap offerings nationwide as a basis for providing the non section 177 

states the same emission reduction benefits as would occur in California and the section 177 

states. One of several benefits of using the PZEV zero evap only option was that there would be 

no end of model year accounting required at the Federal level for the 2017 model year. EPA 

recognizes that the fleet mix in each state is not identical and that in phase-in programs such as in 

Tier 3 (or LEV III) there could be very minor year-to-year differences in the number of Tier 3 

compliant vehicles in any given state. Thus, we see no need for setting the three percent 

requirement suggested by the commenter.

Central to this option is the principle that any PZEV zero evap model (e.g., fuel 

system/powertrain configuration) offered for sale in California and/or any of the section 177 

states must be offered for sale nationwide. This does not preclude a manufacturer from offering 

different fuel system/power train configurations of the same base model for sale nationwide but 

only if they are offered for sale in California and the section 177 states. Stated differently, to 

qualify for this option in the 2017 model year, a manufacturer must offer all fuel system/power 

train /configurations/evaporative control system configurations of a base model it sells in 

California and the section 177 states in the non-section 177 states also. 

High-Altitude testing-FTTP and 3-Day (FR29892)
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What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA indicates the following regarding high altitude 3-day evap.: “We are proposing to keep that 

requirement but to allow for an adjustment of 5°F in the temperatures related to the running loss 

test within the 3-day test cycle. Thus, the applicable fuel and ambient temperatures at §86.134-96 

(f) and (g) would 90±5 °F instead of 95±5 °F for high altitude testing.”

We recommend EPA clarify that all temperature values within the Fuel Tank Temperature 

Profile (established for sea level testing) will be adjusted down by 5°F for high altitude testing. 

Additionally, the hot soak and diurnal temperatures should be adjusted down by 5 °F for high 

altitude testing.

To help reduce the testing burden on industry, we recommend eliminating the high-altitude 3-day 

requirement. The 3-Day test includes higher temperature inputs that are not typically 

encountered at high altitude.

In fact, to further reduce testing burden on industry, we would support removing the 3-Day 

requirement at sea-level as well. 

Our Response:

We agree with the commenter regarding the technical rationale for a 5F° downward 

adjustment in the fuel tank temperature profile for testing at altitude. This has merit because of 

the nature of the evaporative process for 7.8 RVP fuel at the higher tank temperature and lower 

atmospheric pressure a as compared to sea level. The 5°F downward adjustment in the sea level 

fuel tank temperature profiles for high altitude testing is still representative for high altitude and 

control will still occur using the control systems/technical approaches designed for low altitude 

operations. This argument does not apply to the temperature cycle used for the diurnal test 

because temperatures of 96°F or more are encountered in high altitude areas in the ozone 

season17 and manufacturers provided no information supporting changes to these test elements at 

altitude or sea level. Therefore, we are not eliminating the three day test or adjusting test 

temperatures at low or high altitude.

Organization: American Honda Motor Co., Inc.

High Altitude Evaporative Emission Standards:

Under the Tier 3 rule, EPA allows vehicles certified to LEV III to be carried over into Tier 3. 

However, LEV III does not specify high altitude standards. Tier 3 sets less stringent 

standards/requirements for high altitude conditions, due to many, well-understood reasons (e.g. 

lower atmospheric pressure on vapor generation rates, canister loading and purge dynamics, etc). 

In §86.113-04(a)(2)(ii)(C), EPA states that LEV III vehicles must also meet “standards at high-

 

17 See for example, http://coolweather.net/statetemperature/colorado_temperature.htm.
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altitude conditions.” Honda believes this requirement is too stringent, and inconsistent with 

EPA’s intention to relax high altitude obligations. Vehicles that certify to LEV III standards 

should be allowed to meet the relaxed high altitude EVAP standards of Tier 3. 

Our Response: 

We concur with the commenters view regarding hot soak plus diurnal evaporative 

emission standards for high altitude. The intent of this provision is for any LEV III or PZEV 

zero evap carryover vehicles to meet the Tier 3 high altitude standards if it is to be sold outside 

of California. For PZEV zero evap carryover the manufacturers can use Tier 2 or Tier 3 fuel to 

meet the Tier 3 high altitude standards through the 2019 model year. For vehicles meeting the 

LEVIII option 1 or option 2 standards in the 2015 model year and using carryover for future 

model years they can use Tier 2 or Tier 3 fuel to meet the Tier 3 high altitude standards. For new 

Tier 3, LEV III option 1 or option 2 certifications in the 2016 and later model years they must 

use Tier 3 test fuel for the Tier 3 high altitude standards.

What Commenters Said:

Organization: Aston Martin Lagonda Ltd

For evap capability AML recognizes the reasons for EPA wanting to keep all three tests and even 

adding a leak test; however the 3 day test still allows point source running loss testing to be 

accepted rather than full enclosed chamber measurement. In this respect I would propose that 

SVMs certify only using the ORVR test and the 2 day test. The ORVR test effectively drives 

canister capacity requirements. The 2 day test is the best method for validating purge capability 

(backed up with the bleed test) and for driving a diurnal capable system design. The 3 day test 

does not add anything to the validation of an evap system design and in fact with point source 

running loss measurement the 3 day test with its extended diurnal does not prove system 

capability any further than the 2 day test but does incur significant testing burden and cost for 

SVMs. Additionally Aston Martin acknowledges and approves of the removal of the need for the 

leak test at time of certification. 

Our Response: 

The leak test and standard apply at time of certification and in-use, but can be met by 

attestation at time of certification. EPA does not concur with the commenter with regard to the 

three day evaporative emissions test. The commenter’s technical assertions are often but not 

consistently true. For example, for an ORVR system with a mechanical seal, canister volume and 

working capacity may be driven by the three day test. The same is the case for sealed fuel tanks 

used on some hybrid vehicles and for any non-integrated evaporative and refueling system 

canister approaches. Also, it should be noted that another commenter encouraged EPA to 

consider diurnal emissions control for more than three days, not less.

What Commenters Said:
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Organization: California Air Resources Board (CARB)

Evaporative canister bleed test standard in-use requirement:

CARB supports U.S. EPA’s proposal to implement an in-use requirement for the bleed test 

standard. This in-use requirement would ensure that canister performance is maintained as 

vehicles age. Accordingly, CARB intends to propose alignment with this proposal once the Tier 

3 program is finalized. 

Our Response: 

We acknowledge CARB’s support and intention to propose revisions to align with EPA’s 

canister bleed test standard and in-use requirements. 

4.3.2. Program Structure and Implementation Flexibilities

What Commenters Said:

Organization: Volkswagen Group of America, Inc.

VWGoA would also like to request that the Family Emission Limits (FEL) for evap Tier 3 be set 

at a value much lower than the currently proposed 25 mg. This large increment does not provide 

the needed flexibility to ensure success on a fleet wide level. VW requests an FEL of 5 mg. 

Our Response: 

EPA understands that a lower or unfixed increment for the FEL for the hot soak plus 

diurnal standard would potentially lead to greater credits or smaller debits. However, we believe 

the increment we proposed is appropriate. Setting a smaller increment creates the potential for 

false credits which could occur by shaving the compliance margin or by taking credit for the 

decay in non-fuel hydrocarbon emissions which occurs over time on real world vehicles. 

A 25 mg increment means there will be a compliance margin of zero to 24 mg relative to 

the FEL depending on the measured emission level. This is up to 8 percent of the level of the 

standard of 300 mg for LDVs/LDT1s, which we believe is not an overly high percentage. In 

2013 VWGoA certified with compliance margins of 20-80 percent relative to the MSAT 

standards, and the differences between the measured levels and the certified levels were very 

small ranging from zero to 20 percent. The 25 mg increment generally results in a compliance 

margin larger than that for a 5 mg increment, but this is reasonable since, for example, in 2013 

all of VWGoA’s evaporative families certified with a compliance margin of 20 percent or more 

of the standard.18 Finally, it should be noted that participation in ABT is voluntary. 

 

1818 Passavant, G. (February, 2014). “Volkswagen Group of America Evaporative Emissions Certification Data for 

the 2013 Model Year”. Memorandum to the docket.
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What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Cert (FR29887):

Beginning in the 2017 MY, all new evaporative/refueling emission family certifications would 

have to meet the proposed EPA Tier 3 certification requirements for both test procedure and 

certification test fuel for evaporative and refueling emission standards. This statement should 

apply for all new evaporative/refueling certification testing for families certified to the Tier 3 

requirements, not all new evaporative/refueling testing. This requirement should not apply to 

evaporative/refueling families certified to the Tier 2 requirements. 

Our Response: 

EPA concurs with the comment. As specified in the preamble, Tier 3 evaporative and 

refueling test procedures and certification test fuel apply to vehicles brought into the Tier 3 

evaporative emission program. As discussed in the preamble, these requirements vary depending 

on the program option and the applicable standards. They do not apply to vehicles still meeting 

Tier 2 evaporative emission requirements.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA asked for comment on a third option that would require that a manufacturer meet the Tier 3 

evaporative emissions standard on 20 percent of its fleet less than 6,000 pounds GVWR and also 

meet the leak check standard on those vehicles. We support this option and appreciate that EPA 

understands our concerns. We agree that manufacturers could meet the leak check standard on 20 

percent of their MY 2017 fleet; however, since these are independent requirements, there is no 

reason that manufacturers need to overlap the vehicles meeting Tier 3 evaporative emission 

standards with vehicles meeting the leak check standard.

Recommendation:

1. We recommend adding the following as new paragraph §86-1813-17(g)(2).

“(2) For 2017 model year only, you may reduce the percentage phase-in specified in paragraph 

(a)(5) of this section to 20 percent of projected vehicle sales of vehicles at or below 6,000 pounds 

GVWR, if you also certify 20 percent of your vehicles at or below 6,000 pounds GVWR to the 

Tier 3 leak emission standard in paragraph (a)(4) of this section. Also, if you certify vehicles 

above 6,000 pounds GVWR to the Tier 3 evaporative emissions standard in model year 2017, 

you may count projected U.S. sales of those vehicles toward your calculation for meeting the 20 

percent Tier 3 evaporative emissions phase-in requirement in 2017 (numerator only).” 

What Commenters Said:
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Organization: General Motors LLC (GM)

For phasing in the evaporative emission standards, we support a 20% requirement in 2017 

coupled with an alternative phase-in approach starting in 2017 to facilitate the ramp-up to 

national volumes while maintaining equivalent stringency with the California LEV III program. 

This is detailed further below.

Evaporative Emission Phase-in

EPA asked for comment on the Tier 3 evaporative emission phase-in schedule options. One of 

the phase-in options listed would require OEMs to meet the Tier 3 evaporative emissions 

standards in the 2017 model year for 20% of their fleet for passenger cars and LDTs < 6,000 lbs. 

GVWR. These vehicles would also have to comply with the leak check standard. Phase-in 

schedules greater than the 20% option are problematic due to insufficient lead-time and zero 

evaporative system component supplier constraints. Therefore, GM supports a 20% requirement 

in the 2017 model year. 

The evaporative emission phase-in rate is especially aggressive, and the combination of a 20% 

requirement in 2017 along with the allowance of an alternative phase-in approach beginning in 

2017 will provide needed flexibility for expanding zero evaporative system technology 

throughout the U.S. 

Our Response:

The 20/20 option for the 2017 model year is included in the final rule. The number of 

vehicles needed to meet the 20 percent value is based on multiplying 0.2 times the passenger car 

and light truck sales < 6,000 lbs GVWR for the non-section 177 states and excluding California. 

Compliance with this value can be from any vehicle category covered by the Tier 3 program. 

Under the 20/20 program the manufacturer must meet or exceed each of the two values: 20 

percent Tier 3 evaporative hot soak plus diurnal and 20 percent leak standard. These standards 

may be net on the same or different vehicles. Manufacturers utilizing this option will have to 

demonstrate that they meet the 20 percent requirement based on actual sales after the end of the 

2017 model year. There is no flexibility to under comply with one percentage but offset by over 

complying with the other. These vehicles must also meet the 0.020” evaporative system leak 

monitoring requirement which also takes effect in the 2017 model year.

4.3.3. Alternative Phase-in Percentage Approach

What Commenters Said:

Organization: General Motors LLC (GM)

In addition, GM supports the allowance of an alternative phase-in approach, starting in 2017 

model year, which allows flexibility from model year to model year in the phase-in percentage as 
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long as the manufacturer achieves a minimum number of phase-in points equivalent to the 

baseline phase-in percentage.

The evaporative emission phase-in rate is especially aggressive, and the combination of a 20% 

requirement in 2017 along with the allowance of an alternative phase-in approach beginning in 

2017 will provide needed flexibility for expanding zero evaporative system technology 

throughout the U.S. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Alternative Phase-in Percentage Approach: EPA proposes that manufacturers may use an 

alternative phase-in approach that is equivalent to the normal percentage phase-in requirement 

measured over the course of the phase-in period but allows more flexibility between model 

years. Specifically, in lieu of meeting the 60/60/80/80/100% phase-in requirement over MYs 

2018-2022, EPA proposes allowing a manufacturer to meet a phase-in that adds up to a value of 

1040 or greater using the formula 5 x 2018MY% + 4 x 2019MY% + 3 x 2020MY% + 2 x 

2021MY% + 1 x 2022MY%. In addition to providing manufacturers added flexibility between 

model years, this approach also provides an incentive to over-achieve relative to the normal 

percentage phase-in requirement in the early years of the phase-in. We support the availability of 

this alternative phase-in approach. 

EPA also asks for comment on whether this alternative phase-in approach should include the 

2017 model year, based on a 2017 percentage requirement of either 40% or 20%. We support 

including MY 2017 in the alternative phase-in approach based on a MY 2017 requirement of 

20%. As EPA notes in the preamble, the above equation would be modified as follows to 

accommodate this change: 6 x 2017MY% + 5 x 2018MY% + 4 x 2019MY% + 3 x 2020MY% + 

2 x 2021MY% + 1 x 2022MY% must be greater than or equal to 1160. We believe this 

alternative phase-in approach would give auto manufacturers the flexibility they need to ramp-up 

Tier 3 evaporative emission systems to a nationwide level across 100% of their models by MY 

2022. 

Recommendation: We support inclusion of an alternate phase-in, as well as an alternate phase-in 

that includes MY 2017. 

Our Response: 

EPA is incorporating an alternative phase-in scheme which includes the 2017 model year. 

As stated by the commenter, we proposed the alternative phase-in percentage approach and are 

finalizing it including the option to include the 2017 model year for the 20 percent option. 

However, for the 20 percent option in 2017 under the alternative phase-in scheme, the vehicles 

must meet the hot soak plus diurnal, leak standard, and the OBD 0.020” evaporative system leak 

monitoring requirements. Over compliance with the 20 percent hot soak plus diurnal requirement 

could earn “points” toward the required total in the alternative phase-in scheme.
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EPA is also including the 40 percent of passenger cars and light trucks < 6000 lbs 

GVWR option in the alternative phase-in percentage approach if a manufacturer elects that 

option for the 2017 model year. In either the 20 or 40 percent options, compliant vehicles can be 

from any class covered by the Tier 3 evaporative emission standards, but the number of vehicles 

is based on the percentage (i.e., 20% or 40%) of passenger cars and light trucks < 6000 lbs 

GVWR excluding sales in California and the section 177 states.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

End of year validation for non-ABT (FR29887):

EPA indicates the following requirement regarding the Tier 3 Evap. Phase-in: “At the end of the 

model year they would be expected to show that the percentages were met and if not they would 

either use additional allowances or bring more vehicle families into the calculation.”

EPA indicates that the end of year validation with actual production volumes is necessary 

because they allow for fleet averaging.

We recommend EPA clarify that end of year validation with actual production volumes is not 

required if the manufacturer does not participate in the evaporative emissions ABT program (i.e., 

the manufacturer does not utilize FELs or credits/allowances). 

Our Response: 

We do not concur with the commenter. The end of year validation with actual production 

volumes is required to demonstrate that the required sales percentages were met. This is true 

whether or not the manufacturer participated in ABT during the phase-in.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Final Tier 3 Cert (FR29871): “...100 percent of vehicles would need to meet the all Tier 3 

requirements and would be considered ‘Final Tier 3’ vehicles.”

We assume this is in reference to “Final Tier 3” exhaust and not final Tier 3 evap, which will not 

be at 100% until 2022. 

Our Response: 
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The commenter’s interpretation of the NPRM preamble text is correct. “Final Tier 3” has 

no meaning in the regulatory context for evaporative emissions, but the preamble text here was 

referring to the exhaust emission standard program requirements. Evaporative emissions 

requirements are fully phased-in in the 2022 model year.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Credit Trading (FR29889):

Credit trading should be allowed between OEMs. Credit trading between OEMs will not reduce 

the overall stringency of the Tier 3 program. 

Our Response: 

We agree with the commenter and have included credit trading between manufacturers in 

the final program.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

LEV 3 Option 2 (FR29885, FR29886, et.al): Vehicles certified to evaporative emission LEV 3 

option 1 provisions are accepted as compliant to the Tier 3 requirements and are included in the 

percentage calculations. Vehicles certified to the LEV 3 option 2 provisions should be included 

as well. 

Our Response: 

We agree with the commenter that vehicles certified to the LEV 3 option 2 provisions are 

considered compliant and have clarified the description in the preamble (see Section IV.C.1.d) to 

the final rule of the Tier 3 evaporative emissions requirements for vehicles in various categories. 

4.3.4. Technological Feasibility

What Commenters Said:

Organization: Michigan Department of Environmental Quality (MDEQ)

The MDEQ, Air Quality Division supports the more stringent evaporative, leak and refueling 

emissions standards, as well as the new test procedures described in the proposed rule. Control 

of these significant sources of volatile organic compounds, particulate matter, and toxic air 

contaminants have been demonstrated to be cost effective and attainable. California appears to 
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have already implemented a program with many similar requirements, showing that the limits 

can be met. 

Organization: Manufacturers of Emission Controls Association (MECA)

MECA agrees with EPA staff’s assessment that achieving the proposed Tier 3 exhaust and 

evaporative emission standards and associated emission reductions are both technically feasible 

and cost-effective.

Advanced evaporative emission technologies (including advanced carbon canisters and air intake 

hydrocarbon adsorbers) that are available to meet Tier 3/LEV III evaporative emission standards 

for light-duty or medium-duty gasoline or flex-fuel vehicles are discussed in the MECA report: 

“Evaporative Emission Control Technologies for Light-Duty Gasoline Vehicles” (available on 

MECA’s website, www.meca.org, under Resources >> Reports). MECA worked closely with 

ARB in developing the LEV III canister bleed emission testing protocol (also included in EPA’s 

Tier 3 proposal) that provides a cost-effective means of defining the bleed emission performance 

characteristics of carbon canisters used on light-duty or medium-duty gasoline vehicles. 

Including this canister bleed emission test procedure in the Tier 3/LEV III requirements ensures 

that vehicle manufacturers have to meet a minimum canister performance level in complying 

with the “zero” evaporative standards that California first put in place for PZEV-certified 

vehicles. As on the exhaust side, the millions of PZEV-certified vehicles operating on U.S. 

highways today form a solid evaporative technology base that can be extended to all future Tier 

3/LEV III light-duty and medium-duty vehicles. 

Our Response: 

EPA agrees with the commenters. The canister bleed standard helps to ensure that vehicle 

evaporative emissions are near zero. As discussed in Chapter 1 of the RIA there are many 

technology approaches which could be used to reduce evaporative emissions and there are over 

50 models certified to PZEV zero evap requirements for the 2013 model year. 

What Commenters Said:

Organization: Ferrari

Ferrari considers the proposed evaporative emission and PM standards feasible in 2021 MY. We 

therefore support this aspect of EPA’s proposed rule. 

Organization: Northeast States for Coordinated Air Use Management (NESCAUM)

I’d like to quickly mention two other provisions that would contribute to improved air quality 

and reduce public exposure to toxic contaminants in gasoline: reducing evaporative emissions to 

near zero levels from all affected vehicles as is currently the case with hundreds of thousands of 

California certified vehicles on the road in the northeast.
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Organization: Sierra Club

Further, EPA demonstrates that there are a number of technologies in use today that can be 

integrated into motor vehicles to fully comply with the proposed Tier 3 evaporative emissions 

standards. 

Our Response: 

We acknowledge the support of the commenters for this aspect of the proposal.

4.3.5. Evaporative Emission Requirements for Heavy-duty Vehicles (HDV) Requirements

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Chassis-Certified HDV Evaporative Emission Test Procedures: For chassis certified HDV 

evaporative emission test procedures, industry recommends that EPA reference the light-duty 

evaporative emissions test procedures and remove the HDV test procedures from the heavy-duty 

subpart. This would simplify and streamline the regulations and prevent possible inconsistencies 

between the light- and heavy-duty subparts. 

Our Response: 

EPA concurs with this suggestion and we are revising the regulatory text to reference the 

light-duty evaporative emissions test procedures and removing the HDV test procedures from the 

heavy-duty subpart. It will also help to facilitate the introduction of ORVR for HDGVs over 

10,000 lbs GVWR.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

HDGV Cert (FR29895): OEMs should be allowed to certify HDGV >14K GVWR to Tier 3 

(voluntarily) and get credits (allowances). OEMs should also be allowed to optionally group 

>14K HDGV with 10 – 14K GVWR vehicles for certification. 

Our Response: 

In the NPRM EPA asked for comment on allowing voluntary certification to Tier 3 

standards for HDGV>14,000 lbs GVWR if we did not adopt specific requirements. Tier 3 

includes revised evaporative standards for these vehicles, as discussed in the preamble and 
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further in Chapter 4.4 of this summary and analysis of comments, so the comment on that point 

is moot. We agree that HDGVs >14,000 lbs GVWR can be included with those between 10,000 

and 14,000 lbs GVWR for certification purposes, such as in optional chassis tests, but they must 

meet all requirements related to vehicles less than 14,000 lbs GVWR vehicles such as the leak 

standard and OBD requirements.

4.3.6. HDGV Certification Flexibility

What Commenters Said:

Organization: Truck and Engine Manufacturers Association (EMA)

Use of Engineering Analysis for Vehicles Above 14,000 Pounds GVWR:

EPA is proposing to permit manufacturers to demonstrate compliance to evaporative emission 

standards using engineering analysis in lieu of direct testing and supplying test results for 

vehicles above 14,000 lbs. GVWR. (78 Fed. Reg. at 29895; proposed 40 CFR 1037.103(c), 78 

Fed. Reg. at 30098.) This is an important change from the current allowance, which starts for 

vehicles with GVWR above 26,000 lbs. In its proposal, EPA points out that this is the same cut 

point allowed by ARB and would allow one certification method. EPA requests comments on 

this proposal. 

If EPA determines not to exclude HDGVs over 14,000 lbs. GVWR from the evaporative 

emission requirements (see above discussion), then EMA supports this proposal. As EPA points 

out, the proposed change would provide consistency with ARB, and would allow one test 

method, which is of paramount importance to EMA and its members. In addition, few facilities 

exist to test evaporative emissions for those large vehicles. As a result, such an allowance would 

provide needed compliance demonstration flexibility. EMA recommends that EPA add the words 

“above 14,000 lbs. GVWR” after the first use of the word “vehicle” in the opening sentence of 

paragraph 1037.103(c) to more clearly communicate that engineering analysis is available for 

vehicles starting with GVWRs above 14,000 lbs. 

- To the extent evaporative standards are in place for vehicles over 14,000 lbs GVWR, allow the 

use of engineering analysis in place of test data for evaporative emissions compliance 

Our Response: 

EPA acknowledges the conditional support of the commenter and is incorporating the 

proposed change to 40 CFR 1037.103(c) in the final rule.

What Commenters Said:

Organization: California Air Resources Board (CARB)
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Comment 7 - Evaporative certification method for heavy-duty vehicles over, 14,000 lbs. Gross 

Vehicle Weight Rating: The NPRM requests comment on a proposal to modify existing 

certification requirements for heavy-duty vehicles over 14,000 lbs. gross vehicle weight rating so 

that evaporative certifications would rely solely on design parameters and engineering analysis 

instead of emissions testing. LEV III test procedures require engineering analysis and data to 

certify vehicles in this weight category for evaporative emissions, but do not specifically 

preclude emission testing as U.S. EPA is suggesting. Because some auto manufacturers may 

prefer to do actual testing, CARB recommends that Tier 3 include actual testing as a means of 

meeting the evaporative emission requirement. Nonetheless, CARB anticipates providing 

reciprocity to federal evaporative emission certification for these vehicles once Tier 3 is 

finalized. 

Organization: Truck and Engine Manufacturers Association (EMA)

Further Reliance on Design Parameters and Engineering Analysis:

EPA also requests comments on taking an additional step to rely on design and engineering 

analysis. (78 Fed. Reg. at 29895.) Under this approach, manufacturers would be allowed to 

demonstrate that the design of their purge strategy, canister capacity, and overall control system 

would control emissions to the same degree as similar (or comparable) Class 2b or Class 3 

vehicles that meet emission standards when tested over the established measurement procedures. 

This additional compliance demonstration flexibility – specifically, being able to reference 

evaporative emission control strategies used on similar or comparable Class 2b or Class 3 

vehicles to demonstrate compliance with a performance-based standard – clearly is needed for 

large vehicles. Accordingly, EMA supports EPA taking such additional steps. It should be noted, 

however, that EMA’s support of this proposal should not be taken in any way as diminution of 

EMA’s support for performance-based emission standards, of which EMA has been a long-time 

advocate. 

- Provide additional compliance flexibility through the use of design analysis for evaporative 

system compliance to a performance standard 

Our Response: 

EPA agrees with CARB. Testing using designated test procedures and test fuels should 

not be precluded as a means to show compliance with the emission standards. . However, For 

HDGVs over 14, 000 lbs GVWR, certification based on comparison of design parameters and 

engineering analysis relative to certified configurations is permissible. Of course, the results of 

any application for certification are subject to EPA approval.

With regard to EMA’s comments, EPA solicited comment on the idea of a design- based 

certification approach for HDGVs over 14,000 lbs GVWR. EPA acknowledges the conditional 

support of this commenter, but has decided to not to finalize such a provision. We believe the 

use of engineering analysis and data from other HDGVs as prescribed in 40 CFR 86.1037(c) 

provides an equivalent flexibility for certification without precluding the use of testing for 

determining compliance.
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What Commenters Said:

Organization: Truck and Engine Manufacturers Association (EMA)

More Descriptive Provisions Related to Using Engineering Analysis: EPA proposes to add more 

descriptive provisions relating to the use of engineering analysis to demonstrate compliance with 

evaporative and refueling emissions standards. (78 Fed. Reg. at 29895 and 30098; proposed 40 

CFR 1037.103(c)). The more descriptive language, and the addition of an example related to 

evaporative emissions from certain fuel system components that is set forth in the regulatory 

language, provide manufacturers helpful guidance as to EPA’s expectations. EMA recommends 

that the proposed language be finalized. 

- Adopt the proposed descriptive provisions related to the use of engineering analysis to 

demonstrate compliance with evaporative and refueling emissions standards.

Our Response: 

EPA acknowledges the support of the commenter and is finalizing the proposed 

language.

What Commenters Said:

Organization: California Air Resources Board (CARB)

Comment 10 - Evaporative option to use design based certification on gaseous-fueled vehicles: 

Subsequent to adopting evaporative emission standards for gaseous-fueled vehicles, U.S. EPA 

developed designed-based certification procedures for other sources (i.e., for marine vessels 

pursuant to 40 Code of Federal Regulation (CFR) 1060.240). These designed-based certification 

procedures would minimize or eliminate certification emission testing. The NPRM requests 

comment on changing the certification requirements for gaseous-fueled vehicles to a designbased approach, which U.S. EPA contends would allow for a simpler assessment when certifying 

these vehicles. CARB does not support this approach and believes that testing vehicles is still the 

most effective way to ensure system integrity and evaporative emission control. Whole vehicle 

testing also ensures that the evaporative system as installed in the vehicle, rather than its 

individual components, is properly evaluated such that the evaporative emission targets are met. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

CNG/LPG Design Based Cert (FR29907): Industry supports a design based certification 

approach for gaseous fueled vehicles. The evaporative emissions from metallic high pressure 

gaseous fuel systems are very low. 
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Our Response: 

EPA agrees that whole vehicle testing is preferable and would not preclude 

manufacturers from doing so. The test procedures and standards in the CFR still apply to these 

vehicles and could be used by EPA even with this flexibility for design-based certification 

approaches. With regard to gaseous fueled vehicles we do not think that requiring emission 

testing using current test procedures is necessary and meeting design standards is sufficient to 

conclude that the vehicles are meeting emission standards. The fuel storage system designs for 

these vehicles are greatly different than for gasoline-fueled vehicles and they do not use the same 

emission control strategies as used on a gasoline-fueled vehicle. The test procedures are not as 

well suited to evaluate their performance since some aspects of the test procedure are intended to 

evaluate the characteristics and performance of control system approaches which are not used on 

gaseous fueled vehicles.

4.3.7. Evaporative Emission Requirements for FFVs

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

FFV Test Fuel (FR29884): Footnote 277 indicates that splash blended fuel should be used for 

FFV evap testing for Tier 3 certification. To simplify the regulations and reduce the number of 

required test fuels Tier 2 and Tier 3 certified FFVs should be allowed to optionally conduct evap 

testing with the new Tier 3 test fuel. Data carryover on splash blended Tier 2 test fuel should be 

allowed for FFVs certified to Tier 2 regulations. 

Organization: General Motors LLC (GM)

Additionally, the use of splash blended 10 psi test fuel for flex-fuel vehicle (FFV) evaporative 

emission testing, as proposed by EPA, represents an evaporative emission stringency increase for 

FFVs complying with the Tier 3 requirements. This would serve as a roadblock for 

manufacturers to designing and offering FFVs and would also undermine the harmonization with 

California’s LEV III program.

GM recommends that EPA adopt a 9 psi Tier 3 test fuel, and that this same fuel be used for both 

conventional and FFV evaporative emission testing. This would facilitate the timely adoption of 

the Tier 3 regulations and preserve the harmonization with CARB and the LEV III regulations. 

Our Response: 

We have considered the comments on the appropriate test fuel for FFV evaporative 

emission testing, taking into account the vapor pressure of Tier 3 E10 test fuel. EPA has decided 

to use the same evaporative emissions test fuel for conventional vehicles and FFVs. This would

provide harmonization with LEV III and Tier 3 evaporative emission requirements for these 
Tier 3 Summary and Analysis of Comments

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vehicles. More detail on our approach to certification fuel for evaporative and refueling 

emissions testing for FFVs can be found in Section IV.C.5 of the preamble. For our response to 

comments on test fuel for non-FFV evaporative emissions testing, see Chapters 4.5.1 and 4.5.2 

of this Summary and Analysis of comments.

4.3.8. Test Procedures

Vehicle Preconditioning before the Hot Soak plus Diurnal SHED Test 

What Commenters Said:

Organization: Volkswagen Group of America, Inc.

Among the exclusive brands in the Volkswagen group are a group of vehicles that are treated 

exceptionally by developers and owners. These exotic vehicles are still subject to the some 

emission standards regardless of the production volume expected. Therefore these vehicles are 

rare and require special handling to account for vehicle background emissions that may not 

decay us in other models. VW requests exceptions for specialty vehicles in the evap vehicle 

preparation sections of Tier 3. Tires may have to be conditioned even after 12 months, as well as 

the vehicles themselves. A chassis may be several years old with current fuel system components 

removed and installed. This process may contaminate areas of the vehicle that are only ‘cleaned’

by baking off residual hydrocarbon. This should be allowed for all of Tier 3, and requires 

modification to section 1066.814(e). 

Our Response: 

EPA agrees that there are some unique vehicle models that may require special handling 

in vehicle preparation prior to evaporative emission SHED testing for certification. This may be 

the case for specialty vehicles such as when a chassis used in one year’s certification is 

“reconditioned” for re-use in a subsequent year’s certification. In these circumstances, a 

manufacturer may seek EPA pre-approval for revised vehicle preconditioning measures. 

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Baking tires and to remove contamination (FR29898)

EPA indicates that no preconditioning shall be permitted for any vehicle aged twelve months 

from the date of manufacture.

We recommend EPA revise this limitation to address the following contingencies:
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1) If a manufacturer determines that a vehicle with >12 months has been contaminated (e.g., fuel 

spill, refrigerant leak, washer fluid leak, etc) then baking shall be allowed to clean up the 

contamination; 

Our Response: 

We do not agree with the commenter’s request. Spot cleaning of confirmed spills or leaks 

may be requested and approved on a case-by-case basis before evaporative emission testing of 

the vehicle. However, baking of the entire vehicle would create the potential for the removal of 

non-fuel hydrocarbons from the test vehicle which should otherwise be accounted for in the 

vehicle emission certification level.

2) If a manufacturer needs to install tires with less than 12 months from date of manufacture (as 

indicated by the tire manufacture date on tire sidewall) on a >12 month vehicle, baking of the 

tires alone shall be permitted prior to installation on the vehicle. 

Our Response: 

EPA generally concurs with this comment, but this allowance must be requested and 

approved on a case-by-case basis before evaporative emission testing of the vehicle.

What Commenters Said:

Organization: California Air Resources Board (CARB)

Comment 6 - Evaporative emission testing spare tire removal allowance: The proposed Tier 3 

regulatory language (§1066.814) contains an allowance to remove the spare tire during 

evaporative emission testing. This provision conflicts with the text in the NPRM that only allows 

exchanging the vehicle’s spare tire with one that has been aged. CARB supports the proposed 

allowance to exchange the spare tire with an aged one, but does not agree with allowing spare 

tire removal. Such an allowance would reduce the stringency of the whole vehicle emission 

standards, which already account for background emissions, including those from the spare tire. 

Our Response: 

EPA concurs with this comment. The final rule provides that the spare tire may be 

exchanged for a used tire or baked but not removed. This is because non-fuel hydrocarbon 

emissions related to the spare tire were considered when the Tier 3 hot soak plus diurnal 

evaporative emission standards were developed.

SHED FID Ethanol Adjustment Factor

What Commenters Said:
Tier 3 Summary and Analysis of Comments

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Organization: Volkswagen Group of America, Inc.

1. The direct measurement of criteria pollutants has been widely regarded as the technical 

pathway of choice in complying with regulations. Therefore, regulating the use of a FID factor 

instead of allowing direct measurement is alarmingly contrary to this philosophy. Allowing the 

use of photo acoustic or impinger methods, used to measure precisely the amount of alcohols in 

the SHED, provides a robust, direct measurement of fuel-based evaporative emissions. Providing 

a FID factor, which may be arbitrary, also will effectively increase the stringency of the 

standards. Manufacturers will have to account for this factor in their design criteria to minimize 

the confirmatory and In-Use testing risk of the Agency’s desire to use a FID factor. CARB 

provides an optional factor, 1.08, which is clearly not harmonized with EPA. Analysis of real 

vehicle data shows this factor to be smaller than this number. VW requests that a test program be 

developed and executed prior to any factor being introduced in the regulation. This program 

would examine this factor using several OEM and Agency labs, as well as vehicles of differing 

technologies. We look forward to further discussions in this area. 

Organization: General Motors LLC (GM)

2. Evaporative Emission Testing Ethanol Adjustment Factor

In the Tier 3 NPRM, EPA proposes the use of a 10% mass adjustment factor to account for 

alcohol based emissions during evaporative emission SHED testing. In the current proposal, EPA 

specifies the use of a flame ionization detection analyzer coupled with the use of the adjustment 

factor as the only viable option to account for alcohol emissions. GM believes that the 10% 

adjustment factor is far greater than the true magnitude of alcohol based emissions. OEMs 

should be afforded the opportunity to utilize analyzers (i.e., photo acoustic) that measure the 

alcohol contribution during certification and in-use evaporative emission SHED testing. 

Furthermore, GM believes that certification confirmatory and in-use evaporative emission SHED 

testing should be conducted using the same test methodology that was used for the initial 

certification testing. Regarding an adjustment factor, while GM supports the availability of a 

factor as an option, it should be based on a more accurate assessment of the impact of alcohol 

emissions on total evaporative emissions. Therefore, GM recommends that EPA specify the 

actual measurement of alcohol emissions as the baseline for evaporative emission testing, and 

allow use of an adjustment factor as an option. However, EPA should review the available 

industry data to determine a more representative adjustment factor value. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

3. Ethanol Adjustment Factor – Photoacoustic or Impinger

Total hydrocarbon evaporative emissions are measured in a SHED using a flame ionization 

detector (FID). To measure ethanol evaporative emissions, a photo acoustic analyzer (e.g., 

INNOVATM) or a midget impinger sampler with gas chromatograph analysis (hereafter, 

impinger) may be implemented. The FID is less responsive to ethanol emissions than to gasoline 

emissions, requiring that a “response factor” be determined for ethanol. To correctly measure 
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total evaporative emissions with a fuel that contains ethanol, the photo acoustic or impinger 

methods are required to measure the ethanol evaporative emissions independently, and then 

subtract the ethanol contribution from the FID measurement (with the ethanol response factor 

applied). Finally, the FID measurement, after correction for ethanol response, is added to the 

photo acoustic or impinger measurement for ethanol to determine the total evaporative 

emissions.

In the preamble to the Tier 3 NPRM, EPA proposes to use an ethanol adjustment factor of 1.10 

for evaporative emission testing conducted using the proposed E15 certification fuel. 

Manufacturers would use a FID and multiply the measured results by 1.10 to obtain the 

certification or in-use value. EPA admits that the 1.10 ethanol adjustment factor is based on 

worst-case E15 data. The LEV III regulations allow manufacturers to measure actual emissions 

using impingers or photo acoustic analyzers, or an adjustment factor of 1.08 (based on the LEV 

III E10 test fuel).

We would also note that our data suggest that the ethanol adjustment factor should be 

significantly lower than the proposed 1.10 for E15 or 1.08 for E10. Moreover, the factor is likely 

to change based on the test being conducted. Industry data suggest that for the two- and threeday diurnal tests the adjustment factor should be about 1.03; and no adjustment is necessary for 

the other tests (spit back, BETP, ORVR, and running loss). (See attached Ford FFV Evap and 

ORVR Ethanol Adjustment Data)

The proposed Tier 3 regulations state that the adjustment factor would apply to all evaporative 

emission tests – hot soak plus diurnal, refueling, canister bleed, and spit back.

For clarity, the ethanol adjustment factor should not be applied to the spit back emissions test 

since this is mass-based and does not use a FID. Additionally, the SHED ethanol adjustment 

should not be applied to the canister bleed emissions test procedure (BETP) for the reasons 

outlined in the LEV III rulemaking (see Section 12.9, “Hydrocarbon Mass Determination. There 

is no requirement to separately measure for alcohol emissions in this bleed emission test.”)

While the use of a FID would streamline the test procedures, the Tier 3 evaporative emissions 

standards are too stringent to design evaporative systems that provide headroom for both the 

standard and another 10 percent for the ethanol adjustment factor. Consequently, manufacturers 

need the option to test the actual emissions (using either a photo acoustic or impinger) rather than 

using a FID with an adjustment factor.

Recommendation: We recommend that EPA harmonize with ARB requirements allowing the 

measurement of actual emissions using photo acoustic or impingers for all emission 

measurements. If EPA wanted to streamline its own procedures, it could test using FIDs and an 

ethanol adjustment factor: vehicles that pass in this way would pass overall, but compliance 

failures would need to be verified by measuring actual emissions.

In addition, EPA and industry should collaborate to determine and adopt a more representative 

ethanol adjustment factor. 
Tier 3 Summary and Analysis of Comments

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IUVP & EtOH Adj (FR29899)

4. For IUVP testing use an ethanol adjustment factor. Industry is opposed to the use of the 

adjustment factor to account for alcohol during IUVP evaporative emission testing. EPA should 

provide the ability for manufacturers to determine OMHCE results for evap, running loss and 

ORVR using impingers or Innova in place of the 1.10 factor (as we do today for ethanol FFV 

programs which test evap, running loss and ORVR with ethanol based fuels). This allowance is 

necessary because of concerns that the 1.10 factor provided by EPA is too high. 

Our Response: 

The commenters generally acknowledge that a correction for the FID ethanol response is 

needed. EPA agrees with the commenters that they should have the option to measure and 

correct the FID measurement or use a fixed correction factor. However, to prevent arbitrary and 

inconsistent results by using the lower of the correction values on a test-by test basis, the final 

rule stipulates that all testing of any vehicle using the certification evaporative emissions data 

must be based on the approach used for certification testing. This applies to EPA confirmatory 

testing as well as all IUVP and IUCP testing. Also, if the data is approved for carry across for 

certification of other evaporative families or carryover for a subsequent model year’s 

certification the same rules regarding which method will be used to adjust the FID data will 

apply. The commenters also presented the view that EPA’s proposed 1.10 factor for E15 was too 

large based on their data. Although not conducting a test program as requested by VWGoA, 

EPA reviewed the data provided by the Alliance and Global in their comments and supplemental 

information provided by GM. Presuming the use of a test fuel with E10, EPA also reviewed the 

test data provided by CARB to support their adoption of the 1.08 value. Taking the information 

in the datasets together, we believe CARB’s 1.08 value to be conservative but reasonable for the 

intended purpose. Four of the fifteen values calculated by CARB were 1.07 or larger.19 The data 

provided by GM showed seven of twenty points were 1.07 or larger. All of the data provided by 

Ford was less than 1.07.20 The correction factor depends on the vehicle and FID response factor 

and to some degree the FID instrument used (analog or digital) which may explain some of the 

differences. 

Furthermore, EPA considered the manufacturers’ comments that the correction should 

only apply to the hot soak plus diurnal measurement. EPA agrees that the correction should 

apply to the hot soak and diurnal measurements and is not needed for the canister bleed, 

refueling, or spit back measurements. There was no data for the SHED rig test provided by the 

commenters and the running loss data showed some need for correction. Thus, to align with 

CARB, we are applying the requirement for measurement correction to the running loss and 

SHED rig test results, in addition to those from the hot soak and diurnal test. 

SHED Rig Test

 

19

20 Passavant, G. (2013, October). Manufacturer Data on Ethanol Measurements in the SHED. Memorandum to the 

docket.
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What Commenters Said:

Organization: Volkswagen Group of America, Inc.

Evaporative emissions rules are meant to control fuel-based emissions. The only way to truly 

measure fuel-based emissions without the non-fuel emissions confounding the result is to have a 

rig. Having a rig-based certification option will eliminate any tedious evap vehicle setup, such as 

vehicle background and tire conditioning. Methods can be developed to measure rig-type 

emissions In-Use, easing the Agency fears of complex and burdensome testing. VWGoA 

specifically requests EPA to continue to optionally accept the ARB PZEV rig procedure until 

2025MY. W/ also specifically requests a mid-term review of the Tier 3 evap regulations and 

procedures to be completed before the expiration of the rig option currently proposed for 2019. 

Our Response: We do not agree with the commenter. The major shortcoming of the rig test is 

that it cannot be conducted in any confirmatory testing or in IUVP testing without disassembling 

the fuel/evaporative system to remove it from the vehicle. There would be no way to ascertain 

the representativeness of the test results relative to what would have occurred when the 

fuel/evaporative control system was installed in the vehicle. In response to the request for more 

time to use the SHED rig test option, EPA has extended the time we will accept SHED rig tests 

results from California LEV III option 1 certifications through the 2021 model year.

Test conditions

What Commenters Said:

Organization: Revecorp Inc.

Second, the proposed rule leaves evaporative emissions testing temperatures the same and the 

proposed rule even is considering reducing the temperature for the 3-day running loss test. 

Revecorp believes that instead of reducing the upper temperature range limit, it should be 

increased to be more real-world. Ozone is a problem during high temperatures, so the propose 

rule should test vehicles under higher temperature conditions such as at least 100 degrees F. 

Revecorp recommends - All testing should be conducted using fuel which is more similar to 

industry average in-use fuel, evaporative emission tests should be conducted over a wider, higher 

temperature range.... As noted above, all of these changes and test requirements should be 

demonstrated at high altitude. 

Our Response: 

EPA is not removing the 3-day running loss test from the Federal requirements for either 

low or high-altitude testing conditions. EPA did not propose to increase the high end of the 

temperature cycle and does not believe it is appropriate to take such actions at this time in the 

absence of prior proposal.

 
Tier 3 Summary and Analysis of Comments

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Multi-day diurnals

What Commenters Said:

Organization: Revecorp Inc.

Third, if the proposed rule is to achieve larger evaporative emissions reductions, vehicles should 

be designed to capture evaporative emissions for more than two or three days.

Modeling studies such as those conducted by Sam Reddy (presented at the CRC conference in 

2011) indicate that significant evaporative emissions come from vehicles sitting for extended 

periods of time such as on new and used car lots for sale and at long term parking locations such 

as airports. Emissions from these conditions could be reduced significantly by designing 

evaporative emissions control systems to be able to contain more evaporative emissions. If 

testing was required to prove that evaporative canisters do not “break through” in less than four 

days, significant reductions in evaporative emissions could be gained. In addition, requiring 

manufacturers to perform the test out to five days and providing EPA hour by hour 

measurements of evaporative emissions (60 hour observations) would give EPA information 

about vehicles evaporative emission control system and expected in-use durability/performance. 

The cost to for vehicle manufacturers to make this change would be relatively small (increasing 

canister volume). Revecorp believes this is a better solution than the requirement to add a 

supplemental “scrubber” canister, and would achieve the same result or better – at a lower cost. 

Revecorp recommends - ... evaporative emissions test should be conducted for five days with 

hourly data provided to EPA and the standard being no breakthrough until after 48 hours. 

Our Response: 

Data available to EPA indicates that some Tier 2 vehicles emit fuel vapors after the third 

day of the diurnal. However, many went for several days beyond the 3-day period before 

emissions occurred21 The impact of these emissions on the inventory depends on the fraction of 

vehicles which are parked for more than three days, the diurnal temperature conditions when 

they are parked, the state of vapor load on the canister before it was parked, and the fuel vapor 

pressure. Canisters do not breakthrough to an uncontrolled level because diurnal natural back 

purge (20-25% efficiency per day) during cooling allows them to reach a steady-state condition. 

A larger canister volume with more total gasoline working capacity would help to reduce multiday diurnal emissions assuming it was well purged before the extended park. However, this is 

not as straightforward as it sounds because the current test procedure mandates that the canister 

be loaded to breakthrough before the evaporative emissions test sequence begins. Normally, 

purging a canister with a larger volume of carbon or carbon with higher butane working capacity 

carbon takes a greater air volume to purge an equivalent amount of vapor from the carbon. In 

some cases the additional purge air volume may not be readily available on small to mid size 

 

21 Lindner,J., Sabisch,M., Glinsky,G.,Stewart,J.,St.Denis,M.,Roeschen,J., (2013) Multi-Day Diurnal Testing, ERG 

Contract Report to US EPA.
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vehicles/engines. Conversely, a scrubber is a low working capacity carbon which loads easily 

and purges quickly. The activated carbon canister is at the heart of the vehicles 

evaporative/refueling control system and directly impacts compliance for the SHED rig, canister 

bleed, hot soak plus diurnal, refueling, and running loss standards. Accordingly, we are not 

lengthening the duration of the hot soak plus diurnal evaporative emissions tests in this rule. The 

EPA sets test procedures and performance standards to control these emissions. The use of a 

larger canister, a carbon with a greater working capacity, or a canister scrubber is a manufacturer 

decision based on consideration of cost, technology, and compliance issues. 

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

BETP-Fuel/temp profile (FR29896)

EPA indicates that they intend to incorporate the CARB BETP requirements by reference.

If they do so, then they need to add clarification which indicates that Federal fuels/temperatures 

can be used in place of the California fuels/temperatures identified in the CARB regulations. 

Our Response: 

EPA agrees with the commenter and is adding this provision to the regulatory text.

4.3.9. Certification Emission Test Fuels

What Commenters Said:

a. HDGV Test Fuel

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

HDGV Tier 3 Fuel (FR29895)

Industry supports the optional use of Tier 3 test fuel for HDGV testing. 

Our Response: 

EPA asked for comment on permitting the manufacturers to use Tier 3 test fuel for 

evaporative emissions testing if EPA did not adopt the proposed Tier 3 evaporative emision 

standards for HDGVs. EPA is adopting the Tier 3 evaporative emission standards for HDGVs so 
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the point is moot. HDGVs certifying to Tier 3 evaporative emission standards can use Tier 3 

certification fuel as early as the 2015 model year if they want to earn allowances.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

HDGV Tier 3 Cert Fuel (FR28985)

If HDGV evaporative emission or ORVR testing is conducted on Tier 3 fuel, should engine 

exhaust testing be required on the Tier 3 fuel? Evaporative and exhaust testing requirements 

should be independent in the Tier 3 regulations. Therefore, exhaust testing should not be required 

on the same fuel utilized for evaporative or ORVR testing. 

Our Response: 

Subsequent to the release of the NPRM and receipt of the comments, EPA met with 

manufacturers of engine-dynamometer certified heavy-duty gasoline engines and discussed their 

comments. These HDGV engines are not subject to revised exhaust emission standards in the 

Tier 3 rule. The manufacturers stated that procuring and storing Tier 2 fuel for exhaust emission 

testing for the relatively few HDGE test groups is not preferable long term, and they agreed that 

all HDGE test groups should meet the existing exhaust emission standards on Tier 3 fuel by the 

2022 model year. Based on the information EPA received from the manufacturers, the final rule 

provides that a requirement to use Tier 3 test fuel for exhaust emission testing can phase-in until 

the 2022 model year as deemed appropriate by the manufacturers. Also based on feedback from 

the manufacturers, the final rule provides that after the 2022 model year manufacturers can 

carryover certification on Tier 2 fuel for up to five percent of sales for atypical applications such 

a military vehicles.22 Further discussion of these issues appears in the preamble to the final rule.

4.3.10. Application of Evaporative Emission Standards to Fuels Other than Volatile Fuels

What Commenters Said:

Organization: Truck and Engine Manufacturers Association (EMA)

Application of Evaporative Requirements to Gaseous-Fueled Heavy-Duty Vehicles Above 

14,000 Pounds GVWR

 

22

 Passavant, G. (September, 2013).”EPA & Ford Meeting on Issues Related to Tier 3 NPRM”. Memorandum to the 

docket.
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a. EPA has proposed that Heavy-Duty Vehicles over 14,000 lbs. GVWR that run on volatile 

liquid fuel (such as gasoline or ethanol) or gaseous fuel (such as natural gas or liquid petroleum 

gas (“LPG”)) meet the evaporative emission standards of 86.008-10 through the 2017 model year 

(“MY”), and part 86.1813 requirements in MY2018 and beyond. EPA’s proposed requirements 

violate the CAA’s lead time and stability requirements by imposing new standards with less than 

four full model years’ lead time and at the same time other, already-promulgated, future 

standards are set to go into effect, including new GHG emissions requirements in 2017. 

b. EPA requests comment on “adjusting the regulations such that evaporative emissions 

standards apply only to volatile liquid fuels, which is the approach [EPA has] taken for nonroad 

applications (see, for example, 40 CFR 1060.801).” (78 Fed. Reg. at 29899) EMA supports such 

an approach and urges EPA to exclude heavy-duty vehicles that run on gaseous fuel from any 

evaporative emission requirements. 

c. Fuel systems for gaseous fuels such as natural gas (other than LNG) and LPG are not designed 

or intended to vent to the atmosphere and, therefore, do not need to, nor should they, be subject 

to evaporative standards. LNG systems are designed to vent to the atmosphere, but also are 

designed to be able to go substantial periods of time without the need to vent. Moreover, owners 

and operators of LNG-fueled vehicles have substantial incentives to minimize consumption of 

fuel – a very valuable commodity. For example, managers of fleets with LNG fueled vehicles 

monitor LNG fuel systems and vehicle duty cycles to ensure that no fuel is vented, in order to 

prevent fuel waste. 

EMA urges EPA to exclude heavy-duty vehicles that run on gaseous fuel from any evaporative 

emission requirements. At a minimum, EPA should conduct an appropriate cost-benefit analysis 

before including natural gas and LPG-fueled vehicles above 14,000 lbs. GVWR in evaporative 

emission standards.

EMA recognizes that its recommendation to exclude gaseous-fueled heavy-duty vehicles from 

evaporative emission requirements does not fully harmonize with ARB. If EPA were to conclude 

that such requirements were appropriate, EPA, at most, should apply evaporative emission 

requirements only to LPG-fueled vehicles, which is consistent with the current California 

requirements. 

Exclude all gaseous-fueled vehicles over 14,000 lbs. GVWR from evaporative emission 

requirements.

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Refueling Standards (FR29899)

EPA requests comment on using this rulemaking as the proper context for applying the refueling 

standards to vehicles powered by every kind of fuel.
Tier 3 Summary and Analysis of Comments

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We request comment on adjusting the regulations such that evaporative emission standards apply 

only to volatile liquid fuels, which is the approach we have taken for nonroad applications. 

The Alliance and Global Automakers agree with the EPA proposal to adjust the regulations such 

that evaporative emission standards apply only to volatile liquid fuels, as is the approach taken 

for non-road applications and has been an allowed approach under Tier 2 regulations. Excluding 

diesel fuel from the standards because it is nonvolatile and natural gas and liquefied petroleum 

gas because they are not liquid fuels at atmospheric pressure is the right approach and does not 

impact evaporative emission stringency and/or controls. 

Volatile Liquid Fuels (FR29899)

Industry agrees with EPA that evaporative emission certification should only be required for 

vehicles that operate on volatile liquid fuels. 

Organization: California Air Resources Board (CARB)

Comment 5 - Evaporative emission requirements for alternative fuels.

The NPRM requests comment on whether the evaporative emission requirements should be 

modified in Tier 3 so that the standards only apply to volatile liquid fuels, which would 

effectively remove evaporative emission requirements for liquefied petroleum gas and natural 

gas. CARB recommends that U.S. EPA retain the current applicability of the evaporative 

requirements by continuing to require that liquefied petroleum gas and liquefied natural gas 

vehicles certify to evaporative emission standards. CARB currently has an evaporative emission 

requirement for liquefied petroleum gas vehicles. Although existing California evaporative 

control regulations do not specifically include liquefied natural gas, we believe controlling 

evaporative emissions from liquefied natural gas systems is warranted and intend to pursue such 

action in the future. Having an evaporative emission requirement for these vehicles assures that 

system venting does not occur during normal diurnal conditions, and that other sources of 

evaporative emissions are controlled.

Our Response: 

EPA proposed that the Tier 3 evaporative emission standards apply to gaseous fueled 

heavy-duty vehicles. The existing evaporative emission standards apply to all HDVs as per 40 

CFR 86.008-10 and 1816-08 and the proposed standards are contained in 40 CFR 86.1813. EMA 

raised concern with regard to lead time. The final rule provides four model years of lead time for 

gaseous-fueled vehicles. The applicability of the Tier 3 evaporative emission requirements for 

any given gaseous-fueled heavy-duty vehicle evaporative family depends on when it begins 

production in the 2019 model year. If it begins MY 2019 production before the fourth 

anniversary of the signature date of the Tier 3 final rule, the Tier 3 evaporative emission 

requirements would defer to the 2020 model year. If it begins MY 2019 production on or after 

the date which is four years after the anniversary date of the signature of the Tier 3 final rule, 

then the Tier 3 requirements apply for the 2019 model year. In addition, due to the nature of the 

phase-in inherent in the evaporative emissions program, we expect that manufacturers with 
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diverse product lines will have the lead time necessary to meet the Tier 3 phase-in percentage 

requirements while at the same time deferring compliance with the evaporative emission 

requirements for gaseous-fueled vehicles until the 2020 model year or later when the percentage 

requirement is 80 percent. In this case they could choose to include these vehicles in the 

denominator of the percentage calculation in the applicable model year (either 2019 or 2020). 

Small manufacturers have until the 2022 model year to meet the Tier 3 evaporative emission 

standards.

Existing evaporative emission standards apply to all gaseous fueled vehicles including 

natural gas and liquified petroleum gas (LPG) (see 40 CFR 86.008-10 (b)) and 1816-08. EPA 

sought comment on applying the evaporative emission standards only to vehicles using volatile 

liquid fuels (a fuel that is liquid at atmospheric pressure and has a Reid Vapor Pressure higher 

than 2.0 pounds per square inch – gasoline. ethanol, and methanol), but we did not propose it 

explicitly. EPA has examined the comments and once again studied the fuel properties and fuel 

system characteristics for the vehicles covered by the existing evaporative emission 

requirements. Based on this review, we have decided not to change the applicability except to 

add that ethanol is covered as a volatile fuel. The requirements are technically feasible and 

appropriate for the technologies involved. The Tier 3 evaporative emission standards apply to all 

vehicles using volatile fuels (a volatile fuel is a volatile liquid fuel or any fuel that is a gas at 

atmospheric pressure -- gasoline, methanol, ethanol, natural gas, and LPG are volatile fuels). 

EPA has reviewed the evaporative emission requirements relative to the fundamental 

elements of the fuel system designs for these vehicles. Based on this review, we are not applying 

all the various evaporative and refueling requirements, only those that are appropriate given the 

technology. However, we are applying the standards to sealed systems as well as low pressure 

systems. Specifically, EPA has decided to continue not to include the 2-day evaporative emission 

standards and test procedures for gaseous-fueled vehicles. This is largely because these vehicles 

do not use carbon canisters to control evaporative emissions so canister purge does not come into 

consideration. Even though the commenters suggested that gaseous fueled vehicles should not 

be subject to standards due to the nature of their design, EPA believes the running loss and three 

3-day evaporative emissions tests are needed to ensure control of leaks which could arise in these 

sealed systems as a result of mirco cracks and poor connections. The behavior and practices of 

owners, operators, or fleet managers is not relevant to certification. While the test procedures for 

these standards would apply, EPA believes that meeting consensus standards will provide the 

appropriate control and is including regulatory provisions to permit manufacturers to certify 

based on related data, engineering analysis, and compliance with national consensus standards 

such as ANSI, NGV 1-2006. Assuming the use of these compliance flexibilities and elimination 

of the 2-day test, compliance costs should be minor. 

4.3.11. Refueling Emissions Control and ORVR

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)
Tier 3 Summary and Analysis of Comments

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ORVR on Alternate Fueled Vehicles (FR29899)

ORVR requirements should not apply to CNG, LPG, fuel cell or electric vehicles. 

Our Response: 

For LDVs, section 202(a)(6) requires that refueling standards apply to vehicles of all 

fuels. EPA has more discretion for light trucks and heavy-duty vehicles. Existing EPA 

regulations apply the refueling emission standards and related requirements to all complete 

vehicles up to 10,000 lbs GVWR. In the NPRM we asked for comment on the future application 

of the refueling standards to only volatile liquid fuels (a fuel that is liquid at atmospheric 

pressure and has a Reid Vapor Pressure higher than 2.0 pounds per square inch – gasoline. 

ethanol, and methanol) or applying them to all volatile fuels (a volatile fuel is a volatile liquid 

fuel or any fuel that is a gas at atmospheric pressure -- gasoline, methanol, ethanol, natural gas, 

and LPG are volatile fuels).

Based on comments and review of the fuel properties and fuel systems EPA is retaining 

most of its existing requirements and adding new requirements. First, as discussed further below, 

we will no longer require diesel-powered LDTs, MDPVs, or HDVs to certify to the refueling 

emission standard. Second, with regard other fuels (not gasoline) EPA is adding requirements 

for other volatile fueled vehicles (e.g., gaseous fueled) to meet the refueling emission standard. 

EPA agrees in principle that manufacturers and users have incentive to minimize fuel losses. 

However, we believe that the potential exists for vapor losses in such systems from micro leaks 

during the refueling event and during operation and that without including all volatile fuel 

vehicles in the requirement the potential exists for problems to be overlooked either during 

design or installation. Thus, for refueling emissions we have decided to maintain the program 

structure already applied to evaporative emissions and are applying refueling emission standards 

to all complete volatile fuel vehicles including LDTs, MDPVs, and HDVs. 

For LDTs up to and including 8,500 lbs GVWR not already covered by the refueling 

emission standard, the standard would apply to the vehicle when it meets the Tier 3 evaporative 

emission standards. Since control of evaporative and refueling emissions is technically linked, 

we are requiring that when an MDPV or complete HDV less than or equal to 14,000 lbs GVWR 

not already covered by the refueling emission standard meets the evaporative emission standards 

its also meets the refueling emission standard.23 As is the case for evaporative emissions for 

these alternative-fueled vehicles, the applicability of the Tier 3 refueling emission requirements 

for any given family would depend on when it begins production in the 2019 model year. If it 

begins production before the fourth anniversary of the signature date of the Tier 3 final rule, the 

Tier 3 evaporative emission requirements would defer to the 2020 model year. If it begins 

production on or after the date which is four years after the anniversary date of the signature of 

the Tier 3 final rule, then the Tier 3 requirements apply for the 2019 model year. The refueling 

and evaporative emission standard implementation schedule provisions are structured the same 

and vehicles in any evaporative family must meet the Tier 3 evaporative and refueling emission 

standards in the same model year.

 

23 (For vehicles over 8,500 lbs GVWR the Tier 3 refueling emission standards apply only to complete vehicles. See 

the discussion below regarding ORVR for incomplete HDGVs.
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However, due to the nature of the phase-in inherent in the evaporative emissions 

program, we expect that manufacturers with diverse product lines will have the lead time 

necessary to meet the Tier 3 phase-in percentage requirements while at the same time deferring 

compliance with the evaporative emission requirements for gaseous-fueled vehicles until the 

2020 model year or later when the percentage requirement is 80 percent. In this case they could 

choose to include these vehicles in the denominator of the percentage calculation in the 

applicable model year (either 2019 or 2020). 

For complete HDVs over 14,000 lbs GVWR, the refueling emission standard does not 

apply until the 2022 model year, even if the vehicle meets the evaporative emission standards in 

an earlier model year. Small manufacturers have until the 2022 model year to meet the Tier 3 

evaporative emission standards 

For both LPG and CNG the refueling test procedures and standards apply, but EPA will 

deem a system to be in compliance if they certify compliance with relevant national and 

international consensus standards (e.g., ANSI and ISO) related to fuel system and fuel system 

component integrity and the refueling connector.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

ORVR Incomplete Class 3 HDGVs (FR29824, FR29894, FR30051, FR30098)

EPA explains that Class 3 (10,001 – 14,000 lbs GVWR) HDGVs are further sub-categorized into 

complete and incomplete vehicles.

We recommend that EPA clarify that the new ORVR requirement is only applicable to complete 

vehicles, and excludes all incomplete vehicles >8.5K GVWR. 

HDGV Cert (FR29895)

ORVR requirements must exclude incomplete vehicles >8.5K GVWR. 

Our Response: 

EPA concurs with this comment and we are finalizing the new ORVR requirement only 

for complete class 3 heavy-duty vehicles, excluding all incomplete vehicles greater than 8500 lbs 

GVWR. EPA believes that ORVR controls are technically feasible for incomplete HDGVs, but 

at this point, the ORVR requirement applies only to complete HDGVs > 8,500 lbs GVWR 

because manufacturers have indicated to EPA that they would have to establish additional 

measures to ensure that the steps taken to complete the vehicle by the secondary manufacturer do 

not compromise the integrity and safety of the fuel/evaporative control system (including 
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ORVR) and that the ORVR system continues to perform properly with regard to emissions 

control. Incomplete vehicles certified to the ORVR requirements may earn ORVR or 

evaporative emission standard allowances. 

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

ORVR-Reducing gasoline waste on large tanks (FR29895)

For large tanks, the ORVR test generates 50 or more gallons of waste gasoline. Industry would 

like to work with EPA to develop methods to reduce this. We recommend adding the following 

(or words to this effect) to §86.1816-05:

“For vehicles with fuel tanks larger than 40 gallons, manufacturers may request alternative 

ORVR testing to reduce wasted fuel. The request should include data to indicate that testing is 

representative of in use refueling.” 

Our Response: 

EPA agrees that an alternative procedure should be available to address this concern. 

Most if not all gasoline fuel tanks over 40 gallons are found on HDGVs over 14,000 lbs GVWR. 

In response to this comment, we have included a test procedure approach for ORVR for vehicles 

over 14,000 lbs GVWR which will allow the use of a seal test as currently contained in the 

refueling emission test procedure regulations rather than the full SHED test. This gives 

manufacturers the opportunity to demonstrate that their test vehicles have the purge strategy and 

canister design (e.g., geometry, back pressure, and gasoline working capacity) based on 

engineering analysis and comparison to designs used on lighter-weight GVWR HDGVs which 

meet the refueling emission standards and have been certified rather than running the full 

refueling test procedure.

What Commenters Said:

Organization: Private Citizen

These comments were submitted as testimony at the Philadelphia, PA public hearing on April 24, 

2013. 

I was also concerned about some of the vapor and evaporation at gas pumps and whether that 

could be included in this, or whether in a separate rule. So I was thinking along the lines of 

cumulative that you could do, especially when it comes to congressional negotiations that happen 
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when something gets lowered. Perhaps an all-inclusive thing might get to our goal without 

focusing on one small area.

Our Response: 

In May of 2012, EPA finalized a rule to permit states which adopted Stage II vapor 

recovery requirements to remove such requirements if certain Clean Air Act requirements related 

to future compliance with the ozone NAAQSs are met.24 This was adopted because the 

Administrator deemed ORVR to be in widespread use and as provided under the Clean Air Act 

there was no need to continue redundant control (Stage II and ORVR) of refueling emissions 

after ORVR was in widespread use. The Tier 3 rule expands the ORVR requirement further by 

adding the requirement that all complete HDGVs over 10,000 lbs meet the refueling emission 

standards. Nonetheless, the analysis prepared by EPA in support of this decision recognized that 

full fleet turnover to ORVR would not occur for more than a decade. EPA expects many states to 

remove Stage II since the remaining available emission reductions are small relative to the costs 

of maintaining the systems. The hydrocarbon reductions from the Tier 3 will help to ensure that 

current and future plans for compliance with the ozone NAAQS are not impacted.

What Commenters Said:

Organization: California Air Resources Board (CARB)

Comment 9 - Refueling: Modifying the terms for exemption from the refueling requirement for 

diesel vehicles.

CARB does not support U.S. EPA’s proposal to withdraw the condition that the fuel tank 

temperature not exceed 130°F in order for a diesel vehicle to qualify for an exemption from the 

refueling emission requirement absent data showing there would be no emission impact. 

Accordingly, the NPRM should cite any studies supporting such an action. While less volatile 

than gasoline, diesel fuel will still generate vapors, especially under higher temperatures. If the 

original regulatory language is retained, it would likely act to encourage auto manufacturers to 

consider heat exposure when designing and locating the fuel tank, which would result in reduced 

refueling emissions. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

ORVR Diesel (FR29899)

If EPA agrees that diesel ORVR is not a concern (for the same reason diesel is not a concern for 

Evap.), EPA should exempt diesel vehicles from the ORVR requirement (i.e., eliminate the 

standard and requirement for an attestation). 

 

24 See EPA final rule, “Air Quality: Widespread Use for Onboard Refueling Vapor Recovery and Stage II Waiver”. 

77 FR 28772, May 16, 2012.
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Organization: Truck and Engine Manufacturers Association (EMA)

1. Application of Refueling Requirements to Diesel-Fueled Vehicles Above 10,000 Pounds 

GVWR 

EPA proposes in Section 86.1813-17(b)(1) to add a refueling requirement to diesel vehicles 

above 10,000 lbs. GVWR starting with model year 2018. EPA’s proposed requirement violates 

the CAA’s three-year period of stability by imposing new standards near the same time other, 

already-promulgated, future standards are set to go into effect, including new GHG emissions 

requirements in 2017, and also violates the CAA’s four-year lead time requirement. 

Moreover, such a requirement for diesel-fueled vehicles is unnecessary and unjustified. Diesel 

fuel is a non-volatile fuel, as EPA correctly points out in Section 1037.103(a)(2), and, for this 

reason, is excluded from evaporative emissions pursuant to Section 86.016-1(a)(4)(iii).

Furthermore, Section 202(a)(6) of the Clean Air Act, which EPA references to justify the 

application of refueling standards to diesel vehicles, specifically applies only to “new light-duty 

vehicles.” (78 Fed. Reg. at 29899.) As defined in the CAA, light-duty vehicles are those less than 

or equal to 6,000 lbs. GVWR. Thus, diesel-fueled vehicles greater than 6,000 lbs. GVWR are not 

required to be subject to refueling emission standards. 

EMA recommends that all diesel applications be excluded from refueling requirements. If EPA 

desires to expand refueling requirements to heavy-duty applications over 6,000 lbs. GVWR, the 

Agency must conduct a full assessment and rulemaking to demonstrate why such requirements 

should be expanded to diesel vehicles. As the Proposed Rule generally covers vehicles up to 

14,000 lbs. GVWR, in no case should any refueling standard be made applicable to diesel-fueled 

vehicles above 14,000 lbs. GVWR. 

- Exclude all diesel applications over 6,000 lbs. GVWR from refueling requirements 

Our Response: 

One commenter said that the requirement to include diesels above 6,000 lbs GVWR in 

the program was advisable and others indicated that it was unnecessary. In the NPRM, EPA 

indicated that even with turbulent mixing of the dispensed and tank fuel, the very low vapor 

pressure of diesel fuel (<0.05 psi) coupled with the vapor shrinkage conditions which would 

occur during the refueling test (cooler fuel dispensed into a warmer fuel in the tank which then 

condenses vapor in the headspace) make it very unlikely that a diesel vehicle could fail the 0.20 

g/gal refueling emission standard. This is reinforced by the simple chemical equilibrium 

calculations. Consider for example, Table 7.1.2 of AP-42 which indicates a vapor pressure of 

0.022 psi at 100°F for diesel fuel and by interpolation about 9.6 psi for a 9 RVP fuel. A 9 psi 

RVP gasoline fuel gives a refueling emission rate of about 5 grams per gallon. So, a simple 

calculation 5(0.022/9.6) = .011 g/gal. This is only about 6 percent of the standard. In the 

MOVES model used to support the Tier 3 rule we used a zero value for vapor displacement 

emissions. Based on these very low values, EPA is removing the requirement for diesel vehicles 
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to demonstrate or attest to compliance with the refueling emission standard, except for light-duty 

vehicles where it is required under the statute.

4.3.12. Other Comments and Issues

What Commenters Said:

Organization: California Air Resources Board (CARB)

Comment 8 - Evaporative emission testing reduced canister loading allowance for pressurized 

fuel systems:

The NPRM requests comment on allowing reduced canister loading for a pressurized system. 

This load procedure would be proposed by the auto manufacturer to reflect actual diurnal 

canister loading using the manufacturer’s specific technology. CARB is concerned that this 

would reduce the stringency of the test and may result in future vehicles that have inadequate 

ability to purge the canister. The current requirement to load a canister to breakthrough is a 

critical part of the evaporative emission test, which ensures that enough purge capability is 

designed into the vehicle to purge a full canister during an 11-mile FTP drive cycle. While 

CARB recognizes that certain engine technologies in the future will have reduced purge 

capabilities, there are already a number of strategies available today that could help compensate, 

such as heated purge, optimization of purge strategy to maximize use of available engine 

vacuum, and purge pumps. Accordingly, CARB recommends that the canister loading procedure 

remain as proposed. 

Our Response: 

The current load to breakthrough requirement for the canister ensures that purge is 

adequate to achieve control during in-use operation. Under this requirement, the manufacturers 

cannot over size the canister to be sure the test is passed without also providing for adequate 

purge to ensure good in-use performance. At least directionally, this requirement creates a 

disincentive to increase canister size or total working capacity as these situations often require 

more purge air volume to strip the same amount of fuel vapor from the activated carbon in the 

canister. EPA agrees that the possibility of lower purge volumes over the FTP might be 

compensated for by other technologies but this is not without a cost in dollars or weight. EPA 

did not propose a specific change and we received no auto industry comment in support of a 

modification. Thus, we are making no change to this requirement for the Tier 3 rule.

Evaporative Emissions Durability Test Fuel

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)
Tier 3 Summary and Analysis of Comments

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a. Durability Test Fuel: The Tier 2 certification test gasoline, Indolene, contains no ethanol, yet 

the regulations require the gasoline used for evaporative durability mileage accumulation contain 

the highest commercially available ethanol concentration allowed by federal law. We understand 

the historical need for this provision, since the market fuel and certification fuel contained 

significantly different ethanol content. EPA proposes new Tier 3 certification test gasoline 

requirements which would require either 15 percent (proposed) or 10 percent (industry 

recommended) ethanol. Since permeation evaporative emissions remain relatively consistent 

between E10 and E15, manufacturers should have the option to use either Tier 3 test fuel or fuel 

containing the highest commercially available ethanol concentration for mileage accumulation 

on evaporative durability programs.

Recommendation: We recommend EPA provide manufacturers the option to use either Tier 3 

test fuel or fuel containing the highest commercially available ethanol concentration for mileage 

accumulation on evaporative durability programs. This optional allowance could reduce the 

burden on manufacturers to maintain separate Tier 3 test fuel and mileage accumulation fuels 

without any negative environmental consequences. [EPA-HQ-OAR-2011-0135-4461-A1, p.28]

Evap Dura (FR29897):

Revisions to the durability test fuel are discussed. To reduce the number of required test fuels 

EPA should allow the optional use of Tier 3 test fuel for evap durability testing. Evap durability 

demonstration testing should not be required to address the differences between the current 

durability fuel and the Tier 3 test fuel. 

Evap Dura & Market Fuel (FR 29908):

To reduce the number of required test fuels EPA should allow the optional use of Tier 3 test fuel 

for evap durability testing. Evap durability demonstration testing should not be required to 

address the differences between the current durability fuel and the Tier 3 test fuel. 

Also, the language requiring the evap durability service accumulation test fuel to contain the 

highest concentration of ethanol commercially available in any state should be modified. The 

concentration of ethanol in the evap service accumulation test fuel should be specified to match 

the concentration of ethanol in the Tier 3 test fuel. 

Organization: Chrysler Group LLC

EPA should clarify the fuel requirement for evaporative emissions durability testing. The 

regulations, 40 C.F.R. § 86.1824-08(f), require that the fuel manufacturers select for service 

accumulation “contain[] ethanol in, at least, the highest concentration permissible in gasoline 

under federal law and that is commercially available in any state in the United States.” In the 

preamble to and record for the proposed rule, EPA has discussed its interpretation of those 

existing requirements, and particularly the meaning of “commercially available.” It is clear that 

E15, at 0.017 percent of the current market, should not be considered to be “commercially 

available” today. EPA should clarify more generally what “commercial availability” means by 

objective criteria that industry can readily understand. Therefore, as detailed above, evaporative 
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emissions durability fuel should represent that which is the predominate fuel in the market, i.e., 

E10. 

Recommendation: Chrysler recommends that EPA clarify the meaning of “commercially 

available” in the final rule and define it to mean the predominant fuel in the marketplace, 

consistent with our recommendation above, and, currently, E10. 

Our Response: 

EPA did not propose to change the regulations for evaporative emissions durability 

service accumulation fuel, which require such fuel to contain “ethanol in, at least, the highest 

concentration permissible in gasoline under federal law and that is commercially available in any 

state in the United States. Unless otherwise approved by the Administrator, the manufacturer 

must determine the appropriate ethanol concentration by selecting the highest legal concentration 

commercially available during the calendar year before the one in which the manufacturer begins 

its mileage accumulation.’’(See 40 CFR 86.1824-08(f)). While there are only minor permeation 

differences between E10 and E15 for the materials and systems evaluated we believe it is 

important that evaporative systems are designed to meet the emission standards over their full 

useful life. E15 is the highest ethanol concentration allowed in gasoline under federal law and 

this fuel is commercially available. We cannot predict with certainty whether the use of E15 will 

become more widespread in the future but with a 15 year useful life for many Tier 3 vehicles it is 

prudent that evaporative system components have the durability to perform well when this fuel is 

encountered. Most manufacturers use bench aging for their evaporative system components, so 

there should be less compliance burden. If E15 in-use fuel becomes progressively more 

available, we would expect that E15 service accumulation fuel would be used for whole vehicle 

evaporative durability programs.

Deterioration Factors

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Carryover Durability Data: Deterioration Factor (DF) determinations are very resource intensive, 

so we would like to use the DFs generated for Tier 2 (or LEV II) on Tier 3 vehicles. This should 

yield a higher DF than if manufacturers developed a new DF using Tier 3 vehicles, since both 

variation and deterioration tend to go down with emission standards (lower standards = lower 

DF). However, as proposed, the regulations would not allow a manufacturer to carry over a DF if 

the useful life test point exceeded the new emission standard (300 mg). Since the Tier 2 and LEV 

II evaporative standards were higher than the Tier 3 and LEV III evaporative emissions 

standards, this provision would prohibit the use of much of the manufacturers’ durability data.

It’s likely some of the vehicle full useful life tests will exceed the new standards. However, the 

purpose of the DF is to establish the change in emissions as the vehicle ages, and using the Tier 2 
Tier 3 Summary and Analysis of Comments

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data should be a conservative means of achieving this information. California recognized this 

temporary concern and allowed that carryover data from LEV II evaporative emissions 

certification would be capped at the LEV II evaporative emission standards. This is a transitional 

issue (and a conservative one), since manufacturers will begin conducting durability testing on 

the new Tier 3 evaporative emissions standards as the program phases in.

Recommendation: To prevent very expensive and unnecessary testing and harmonize with the 

California LEV III, we request that EPA cap carryover durability data evaporative emission at 

the Tier 2 evaporative emission standard limits. 

Additionally, evap durability carryover should be capped at LEV 2 evaporative emission 

standard levels. This would align the Tier 3 regulations with the LEV 3 regulations. 

Organization: Chrysler Group LLC

Additionally, evap durability carryover should be capped at LEV 2 evaporative emission 

standard levels. This would align the Tier 3 regulations with the LEV 3 regulations.

Our Response: 

EPA understands the premise of the request and agrees that in most cases an evaporative 

emissions DF based on Tier 2 technology would be likely to be numerically larger than an 

evaporative emissions DF based on Tier 3 technology. The allowance requested by the 

commenter, is often referred to as line crossing, is not prohibited in the EPA regulation. EPA 

regulations at §86.1824-01 permit manufacturers to develop their full-useful life deterioration 

factors for evaporative and refueling emission standards based on the use of good engineering 

judgment. These DFs are additive in nature, and when added to the “undeteriorated low mileage” 

test value the sum must be less than the applicable emission standard or FEL. Manufacturers 

usually certify such that this summed value falls below the emission standard or FEL enough to 

provide a margin for in-use compliance and to address variability and other uncertainty. 

Regulations (at §86.1824-08) require that evaporative emissions durability assessments must 

employ gasoline fuel for the entire mileage accumulation period which contains ethanol in, at 

least, the highest concentration permissible in gasoline under federal law and that is 

commercially available in any state in the United States (currently E15). Thus, EPA is 

permitting the use of this data but requires that: (1) the manufacturers use good engineering 

judgment in the testing used to develop their deterioration factors and the assessment and 

application of this data in developing deterioration factors, (2) the manufacturers use the 

evaporative/refueling emissions test fuel as required in the applicable regulations for Tier 3. The 

comment states that “It’s likely some of the vehicle full useful life tests will exceed the new 

standards.” Under current EPA provisions it is possible that the data used to develop the DF 

could have a measured emission point above the standard, but the addition of the deterioration 

factor to the low mileage test result must not result in an exceedance of the Tier 3 emission 

standard or the FEL (under ABT).

Miscellaneous
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What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

UL (FR30072):

Evap and exhaust useful life are associated in §86.1813-17(a)(5); however, they should be 

treated independently in the Tier 3 regulations as described in the preamble, page 29886 

Our Response: 

During the Tier 3 evaporative emission program phase-in years (2017-2022 model years), 

the exhaust and evaporative/refueling systems may have different useful life values if both 

systems are not yet meeting the Tier 3 evaporative emission standards. However, the effective 

operation of the engine and evaporative systems are interdependent and both need to operate 

effectively to get the required in-use performance. A different useful life for exhaust and 

evaporative system standards is counter to this important design premise.

What Commenters Said:

Organization: California Air Resources Board (CARB)

Comment 4 - Evaporative emission standards specifically for when an auxiliary (non-road) 

engine is installed in a motor vehicle.

CARB supports U.S. EPA’s proposal to extend evaporative emission requirements to auxiliary 

non-road engines installed on motor vehicles. This would provide additional control of 

evaporative emissions. Accordingly, CARB intends to propose alignment with this proposal once 

the Tier 3 program is finalized. 

Our Response: 

We acknowledge CARB’s supportive comments and plans to propose alignment on this 

requirement. The Tier 3 NPRM proposed that any vehicle with an installed auxiliary engine and 

fuel system must be tested in the SHED for hot soak and diurnal emissions with the fuel tank and 

fuel system installed. The tank should have a 40 percent fill of the appropriate fuel. If the 

propulsion engine and the auxiliary engine used the same fuel then they should be of the same 

specification. EPA is finalizing this requirement because emissions of these engines are part of 

the overall vehicle system. EPA expects that in many cases these engines will already have some 

form of evaporative controls as part of the nonroad program, but there is the potential that they 

will not be integrated into the vehicle correctly (e.g., placed near a heat source or there is 

insufficient purge) or the engine-based controls may not be sufficient to allow the vehicle as a 

whole to pass the Tier 3 emission evaporative standards. 
Tier 3 Summary and Analysis of Comments

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What Commenters Said:

Organization: Revecorp Inc.

The proposed regulation does not require sufficient in-use compliance testing.

Revecorp believes that in-use compliance testing for tailpipe and evaporative emissions must 

also be performed at high altitude. Proving compliance during certification does not prove that 

emissions control system designs are durable. For example, Revecorp’s firsthand experience 

working on various studies and reviewing the literature indicates that there are many common 

failures of evaporative emissions control systems in-use. These include:

Evaporative emissions purge valves sticking closed – This leads to a lack of purge of evaporative 

emissions, therefore the canister is overwhelmed and emissions escape through the vent.

Canisters are placed in bad locations – This leads the canisters to age prematurely and crack 

allowing emissions to escape to the environment as opposed to be drawn into the engine and 

burned.

Canisters with bad intake locations (such as at the top of the wheel well) – This leads to the 

canister ingesting dirt in-use and then the dirt deactivating the charcoal in the canister. This again 

leads to evaporative emissions escaping continuously from the canister. This condition was 

found in a pair of identical vehicles recruited in for CRC study E-91, indicating it was a design 

flaw which would only be found with in-use testing.

Revecorp’s interpretation of the proposed rule is that in-use verification program (IUVP) 

requirements are not being strengthened for tailpipe emissions testing and there are no IUVP 

requirements for evaporative emission testing at high altitude. As noted previously, if 

engineering demonstration is allowed and there is no IUVP requirement for evaporative emission 

control systems at altitude, manufacturer deficiencies will never be discovered. 

Revecorp recommends – Vehicle manufacturers should be required to prove in-use compliance 

for both tailpipe and evaporative emissions, at both sea level and at high altitude. 

Our Response: 

EPA does not agree with the commenter’s assertion regarding the need for IUVP at high 

altitude to assure system performance. As reflected in the commenter’s experience and our 

recently completed study on evaporative system diagnostic trouble codes (DTCs) from OBD 

systems interrogations in I/M programs, evaporative systems do not perform flawlessly. 

However, purge related codes were found in less than 0.5 percent of all vehicles which had the 

evaporative system OBD monitor ready when they entered the I/M lane.25 This is not to suggest 

 

25 Weatherby, M., Sabisch, M., Kishan, S. (February 2014) Analysis of Evaporative On-Board Diagnostic (OBD) 

Readiness and DTCs Using I/M Data.
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that purge valve failures are acceptable but to note that (1) they are not common and (2) OBD 

finds them without IUVP Overall this is a relatively low rate but reliability of the operation of 

the purge valve in use deserves further study and consideration. 

In the NPRM, we discussed the issue of failed canisters and laid out the idea that a 

malfunctioning canister (whether it is from “poisoning” or a blocked purge air valve) should be 

monitored as part of OBD. Manufacturers disagreed with EPA on the feasibility monitoring for 

canister failures, but EPA believes this is feasible. More information on the frequency of canister 

problems in use is needed before we consider adding an OBD requirement to address this 

potential concern. EPA is undertaking a study in response to this question. 

Furthermore, the commenter indicated that IUVP testing at high altitude would be useful 

in finding problems such as those related to the purge valve failures or non-functioning canisters. 

EPA notes that IUVP testing at any altitude would find problems if they occurred on the vehicle 

tested. Current pass rates for exhaust and evaporative emissions in IUVP exceed 90 percent. 

Specifically with regard to evaporative controls, the sample sizes are small and it is not clear that 

adding an IUVP requirement for SHED testing at high altitude would be of great benefit. 

What Commenters Said:

Organization: Revecorp Inc.

The proposed rule is not protective enough of the health of Americans living at high altitudes and 

population growth continues in these areas at a rate that exceeds the average for the US.

Although only approximately 5% of vehicles operate at “high altitude” (as the NPRM notes), the 

proposed TIER 3 rule is a national standard. This national standard must protect all human health 

- regardless of location or altitude. Revecorp is concerned that the proposed TIER 3 rule 

compromises on testing requirements by allowing for “engineering demonstration” of how 

evaporative emissions control systems will function at altitude, as opposed to requiring actual 

testing. This could lead to vehicles being produced which are not compliant. [EPA-HQ-OAR2011-0135-4816-A2 p. 2]

Evaporative emissions are especially difficult to control at high altitude and as EPA notes, they 

account for 30 to 40% of hydrocarbon emissions including toxics such as benzene. 

Unfortunately, evaporative emission control systems perform worse at high altitude due to 

reduced atmospheric pressure. In addition, newer technologies, which the vehicle manufacturers 

are just now gaining experience, are making it more difficult for these systems to function 

effectively. Gasoline direct injection (GDI) and variable valve timing (VVT) are becoming more 

popular due to fuel economy regulations. Unfortunately, both reduce pumping losses across the 

engine and therefore reduce the vacuum available to purge the evaporative emissions canister 

completely. Another detrimental trend for evaporative emissions control systems is that many 

manufacturers are downsizing vehicle engines to improve fuel economy and making up for the 

loss in performance by turbocharging. Turbocharging causes a loss of vacuum, so strategies to 

completely purge the canister are becoming more complex. The lower vacuum is a bigger 
Tier 3 Summary and Analysis of Comments

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problem at altitude. As a result of the lower barometric pressure, typical vacuum levels are 

reduced by 20% at 5,000 feet and more at even higher altitudes. Additionally, the lower fuel flow 

required to maintain stoichiometric air fuel ratio at high altitude areas severely limits purge 

options. Therefore, more sophisticated strategies need to be developed and should be physically 

tested and proven at altitude. In addition, high levels of dust and particulate matter exist at the 

semi-arid high altitude areas of the US. The high level of dust and particulate need to be 

accounted for in the design of the evaporative control system and again need to be physically 

verified as part of an in-use compliance program. 

At high altitude, all of the above problems become even more difficult to overcome due to the 

reduced atmospheric pressure. Allowing vehicle manufacturers to use “engineering 

demonstrations” (showing on paper how the systems “should” work at high altitude) to prove 

that new technologies will function at high altitudes could allow evaporative emissions control 

systems which do not function properly or are not durable to be put into production. If these 

systems are not designed properly, there is no in-use compliance testing for these vehicles to 

identify any deficiencies so vehicles could have high evaporative emissions for their lifetime.

The proposed rule also notes that the new canister bleed standard would not apply at high 

altitude. Due to the reduced atmospheric pressure, this test should be required to ensure the 

system is working properly. 

Revecorp recommends - All testing (tailpipe, evaporative and canister bleed test) should be 

required to be performed at high altitude to protect the health of all Americans, including those 

living at high altitudes. 

Our Response: 

EPA understands the basis for the commenter’s concern but does not agree with the 

conclusion. One can always propose that more testing is preferable, but this must be tempered 

against a reasonable expectation of the value added and the cost. In the case of evaporative 

emissions control EPA does not have information or data to indicate that specific high altitude 

testing requirements is needed. 

The key factors which govern compliance are vapor generation (ambient and fuel 

temperatures and RVP), canister load (vapor generation rates, canister architecture, and activated 

carbon characteristics), and purge (air mass and volume).The basic chemical and physical 

principles governing these three processes are well understood and have been modeled 

extensively. This understanding creates the basis by which engineering analysis of system 

designs and data at low altitude can be used to predict compliance with the standard at high 

altitude. More specifically, manufacturers understand and characterize how evaporative systems 

operate at low altitude and conduct tests to show compliance with the emissions standards. With 

knowledge of the system characteristics for the vehicle at low altitude, models, engineering 

analysis, and good engineering judgment can be used to predict how they would perform at high 

altitude where there may be different conditions. A good example is purge. Manufacturers know 

how much purge air volume is needed to prepare the canister for evaporative and refueling vapor 

loads and how much volume is generated on that vehicle as a function of available manifold 

vacuum pressure. If the calibration changes at altitude and this reduces the purge volume, 
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adjustments may be needed depending on compliance margins and other system design factors. 

Similarly, the working capacity of the activated carbon in the canister depends on the partial 

pressure of the evaporative emission constituents such as butane and pentane. The canister 

working capacity determined using low altitude testing methods may need to be adjusted to 

assure the same working capacity at high altitude due to the effect of the lower atmospheric 

pressure on the evaporative emission constituent partial pressures. 

This situation is simpler for exhaust emissions since the air/fuel ratio is governed by 

feedback controls from the oxygen sensor. Adjustments are made automatically by the onboard 

computer.

Nonetheless, in many cases manufacturers do some developmental testing at high altitude 

to confirm the relationship between system performance at low and high altitude. They then use 

those results as a basis for future analysis and extrapolation of high altitude performance based 

on low altitude system characteristics and calibrations.

4.4. Onboard Diagnostics (OBD) Comments

4.4.1. General OBD System Regulation Changes 

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global) 

1. Tier 3 contains a number of changes to the EPA OBD regulations. Namely, beginning in 2017, 

Tier 3 adopts all of the latest California OBD regulations and adds a requirement to monitor 

“distance since 0.02-inch evaporative monitor decision” and report that value to a scan tool. The 

adoption of ARB’s latest OBD regulations will include both rate-based monitoring and the 0.02-

inch evaporative emissions leak check monitor. We generally support the changes proposed. 

2. CARB is currently proposing some changes to its OBD program in response to the LEV III 

program exhaust emission standards. We request comment on incorporating these changes into 

this rule or other rules in the future. We support ongoing harmonization with the CARB OBD 

regulations, especially if CARB makes adjustments to lead time, phase-ins or stringency of 

provisions. If EPA adopts the California OBD regulations by reference, it will important for 

EPA to update the reference by regulation in a timely manner. For this rulemaking, EPA should 

adopt the latest version of the ARB OBD regulations (i.e., as amended 7-Aug-2012). 

3. EPA notes, ‘We also would generally expect to continue the current practice allowed by EPA 

regulations which is for EPA to accept CARB OBD certifications as satisfying EPA 

requirements provided that they include at least all of the requirements covered by the EPA 

regulations” [78 FR 29905]. We support that EPA continue the current practice to accept 

California OBD certification as satisfying EPA requirements, and this provision continues to be 

important to ensure OBD certification [EPA-HQ-OAR-2011-0135-4461-A5, p4]
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4. MY 2017 Implementation of California OBD Requirements 

EPA also plans to align its overall OBD regulations with those in California and has proposed 

the same MY 2017 start date for all other OBD requirements. The same concerns about applying 

OBD requirements in the initial year of the regulation for the Distance Since Evap Monitoring 

Decision and CA OBD Leak Detection Monitor at 0.02” apply for the overall requirements. For 

this reason, as well as for simplicity, we recommend the same phase-in for the overall OBD 

requirements, aligning with the phase-in for the evaporative emission standards to maintain a 

single, streamlined phase in for all OBD requirements. 

If EPA is unwilling to phase-in the overall California OBD requirements with the Tier 3 leak 

emissions and evaporative emissions standards, we recommend that EPA provide an option for 

manufacturers to phase in the requirements at a rate of 30/60/100% beginning in MY 2016– a 

year earlier than would otherwise be required – while still maintaining the 60/60/80/80/100 

starting in MY 2018 for the Distance Since Evap Monitoring Decision and CA OBD Leak 

Detection Monitor at 0.02”. EPA should also allow the OBD alternative phase-in (using the point 

system) for this option.

Recommendation: We recommend that EPA provide a phase-in for the overall California OBD 

requirements consistent with the phase-in for the other Tier 3 OBD requirements - Distance 

Since Evap Monitoring Decision and CA OBD Leak Detection Monitor at 0.02” – which we 

have recommended aligning with the corresponding leak emissions standards (60/60/80/80/100 

starting in MY 2018). 

Alternatively, EPA could offer a separate phase-in for the overall OBD requirements, not 

including the Distance Since Evap Monitoring Decision and CA OBD Leak Detection Monitor at 

0.02”, of 30/60/100% beginning in MY 2016. EPA should also allow the OBD alternative phasein (using the point system) for this option. 

Our Response:

EPA proposed to adopt, with a few adjustments, the CARB regulatory requirements 

related to OBD II (see California Code of Regulations (CCR) §1968.2 dated May 18, 2010). We 

received comment that since our NPRM was issued, CARB was completing an update of its 

OBD II regulations and that EPA should adopt these provisions in lieu of the May 18, 2010 

provisions. We have reviewed these updates and concur with the commenters, so we are 

adopting the provisions officially approved by CARBs Office of Administrative Law on July 31, 

2013, with certain adjustments and exceptions discussed in the preamble. As mentioned in the 

NPRM and supported by the commenters, EPA expects to continue to work closely with CARB 

on future OBD updates and to continue the current practice allowed by EPA regulations which is 

for EPA to accept CARB OBD certifications as satisfying EPA requirements provided that they 

include at least all of the requirements covered by the EPA regulations.

Several commenters requested a phase-in compliance approach in lieu of a fixed 

compliance date, but no specific justification was provided by the commenters and EPA could 

not establish a need for this accommodation since the most recent changes to CARB OBDII 
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regulations (2013) did not meaningfully affect provisions regarding vehicles under 14,000 lbs 

GVWR which have been in place since 2006. LDVs, LDTs, MDPVs and vehicles under 14,000 

lbs GVWR already comply with CARB OBDII requirements and use the CARB certification as 

the basis for EPA certification. However, EPA agrees that phase-ins may be appropriate in 

situations where there was an explicit Federal requirement that was less rigorous than the 

California OBDII requirement (e.g., 0.020” evaporative leak monitor) and when there is a new 

Federal requirement (e.g., Distance Since Evap Monitoring Decision). After considering the 

comments received, EPA is permitting a limited and minimal phase-in for the 0.020” leak

detection criterion for the OBD evaporative system monitoring requirement. We are permitting 

this phase-in, because a few vehicle models still only meet the 0.040” monitoring threshold in 

their Federal configuration and complying with the 0.020” CARB OBD II requirement entails 

validating performance in high altitude and cold weather regimes not seen in California. Thus, 

the 0.020” requirement would be new for those few models currently certified only to the EPA 

evaporative leak monitoring requirement. We are, therefore, implementing the following phasein provision for the 0.020” leak detection criterion for the OBD evaporative system monitoring 

requirement. First, if a vehicle model meets the 0.020”requirement in the 2016 model year it is 

not eligible for the phase-in provision. No backsliding is permitted. Second, for manufacturers 

with models not meeting the CARB OBDII evaporative system leak monitoring requirement in 

the 2016 MY(see CCR 1968.2(e)(4)), they will be permitted to delay product-wide compliance 

with the 0.020” leak provision of the evaporative system monitoring requirements until the 2018 

model year by engaging in a voluntary early phase-in. This phase-in would begin in the 2016 

model year and conclude in the 2018 model year at a 100 percent implementation rate. For 

example, a manufacturer could delay attaining 100 percent compliance with the OBD 

evaporative system leak monitoring requirement until the 2018 model year by complying in the 

2016 model year using a percentage which is at least as large as the delay for the 2017 model 

year (e.g., 40% in 2016 MY, 60% in 2017MY, and 100% in 2018MY). 

What Commenters Said:

Organization: California Air Resources Board (CARB)

Comment 1 - Version of OBD II Regulation Adopted:

Overall, CARB supports U.S. EPA’s incorporation of the OBD II regulation section 1968.2 into 

the federal requirements. However, CARB adopted additional changes to the 2010 version of the 

OBD II regulation that is referenced in the proposal. Specifically, CARB adopted changes which 

became operative on August 7, 2012. The 2012 amendments to the OBD II regulation are 

considered minor and include changes to the permanent fault code requirements and in-use 

monitor performance requirements to address issues related to hybrid vehicles (including plug-in 

hybrid electric vehicles), delays to the required start date for three minor diesel-related monitors, 

and an extension to the allowance for particulate matter filter monitors to exclude detection of 

specific failure modes. CARB recommends that U.S. EPA adopt the more recent version of the 

OBD II regulation to be more closely aligned with California. 

Our Response: 
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EPA agrees and is adopting the 2013 version of CARBs OBD II regulations (13 CCR 

1968.2), with certain adjustments and exceptions, as discussed in the preamble.

What Commenters Said:

Organization: Appalachian Mountain Club (AMC)

Overall we support these provisions including the adoption of the California Onboard Diagnostic 

System (OBD) requirements. 

Organization: Michigan Department of Environmental Quality (MDEQ)

The US EPA is proposing to update the OBD regulations to parallel the California Air Resource 

Board’s current requirements. This shows the requirements can be accomplished while 

simultaneously making it easier for car manufacturers to have fewer regulatory requirements to 

track and for which to adjust. 

Our Response: 

EPA agrees and is adopting the 2013 version of CARBs OBD II regulations (13 CCR 

1968.2), with certain adjustments and exceptions, as discussed in the preamble. We expect to 

continue the current practice allowed by EPA regulations which is for EPA to accept CARB 

OBD certifications as satisfying EPA requirements provided that they include at least all of the 

requirements covered by the EPA regulations.

4.4.2. Specific Revisions to EPA OBD Regulatory Requirements

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

1. We recommend several additional changes below. These changes will streamline the 

requirements and recognize that manufacturers begin at different levels of compliance with the 

regulations. 

Storing information in Non-Volatile RAM (NVRAM) and clearing codes:

As proposed, §86.1806-17 would require the vehicle to store the last evaporative leak check 

result, and the distance (in miles) since that result was determined. Further, the leak check results 

(both results and miles since determination) must be scan readable (i.e., readable with a generic 

scan tool). We agree with these changes, and the SAE J1979 committee is developing a PID to 

store the miles since determination. The regulation would also require that the leak check 

results and mileage since determination be retained in system memory even if codes are cleared 

or the vehicle battery is disconnected. This would require manufacturers to store the results and 
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mileage in NVRAM. Currently, vehicles only store permanent fault codes (i.e., when a monitor 

fails a component) in NVRAM. Expanding that memory is both costly and time consuming. We 

understand that the intent of this requirement is to be able to determine 1) if the monitor has 

made a pass/fail determination within the past 750 miles and 2) whether the determination was 

either “pass” or “fail.” The requirement to store this in NVRAM was designed to prevent a 

situation where a vehicle could pass the Leak Emissions Standard test by disconnecting the 

battery or clearing the OBD codes. We support this intent, but believe it can be accomplished 

much more efficiently. By simply resetting the “distance since determination” PID to maximum 

value (40,722 miles) when codes are cleared or the battery is disconnected, the PID would only 

reset to zero when an evaporative monitoring pass/fail decision is made. This would prevent a 

vehicle from passing the IUVP leak emissions standard test by simply disconnecting the battery 

or clearing codes, since the vehicle would not meet the requirements for determination within 

750 miles. Moreover, since the counter will only reset after the evap monitor has made a 

decision, and since the absence of a DTC will indicate that the monitor passed and the presence 

of a DTC will indicate it failed, there is no need to store the pass/fail decision in NVRAM. The 

SAE J1979 Committee is currently developing the requirements for the “Distance Traveled Since 

Evap Monitoring Decision” PID and will include the requirement to set the PID to maximum 

value when the codes are cleared or when the battery is disconnected, and only reset the counter 

to zero when the evaporative emissions monitor has made a pass/fail decision.

Recommendation: To implement this proposal, we recommend the following change to §86-

1806(b)(1):

(1) OBD systems must record in computer memory the result of the most recent successfully 

completed diagnostic check for a 0.020 inch leak The required data must be able to be used to 

determine records include the miles driven since the last check occurred, and-the pass/fail result, 

and if there has not been a completed check since the computer memory was last cleared (e.g.,

from a scan tool command or battery disconnect). The system may be designed to keep data only 

from the previous 750 miles of driving. The leak check results data must be reported in a 

standardized format consistent with other data required for the 080 system. scan readable, and 

must be retained in system memory even if codes are cleared or the vehicle loses battery power.’ 

Organization: California Air Resources Board (CARB)

Further, U.S. EPA is proposing vehicles support and report a new standardized data parameter 

that will be used to indicate the distance traveled since the OBD evaporative system leak monitor 

was last completed successfully, if the system passed or failed during the monitoring event, and 

to store this data in non-volatile memory such that it can survive battery disconnects and onboard computer memory clear events. This proposed requirement is intended to determine 

whether off-board leak detection testing needs to be performed on individual vehicles during the 

In-Use Verification Testing (IUVP) program. 

Concerning the proposal for a new standardized data parameter, CARB has worked with the 

SAE J1979 committee to develop an updated standard to achieve this. However, the draft SAE 

proposal created to meet the intent does not completely align with the U.S. EPA proposed 

regulatory language. Specifically, it does not provide for the data to be stored in non-volatile 

memory but instead has the value report a clear indication if the data has been erased and the 
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monitor has not successfully run since then. In this situation, it appears to CARB that this will 

satisfy the intent and provide a clear indication that the off-board leak test should be performed 

on such a vehicle selected for IUVP testing. Secondly, the draft parameter indicates the mileage 

since the last successful test completion but does not directly indicate whether it was a pass or 

fail decision. Instead, current fault code status must be used and the absence (or presence) of an 

evaporative system leak fault code will confirm whether the monitor last ran and passed (or 

failed, respectively). Again, CARB believes this will provide the necessary data for the intended 

use in IUVP testing. Accordingly, CARB recommends the proposed language be modified in the 

final proposal to eliminate the requirement that the new data be able to survive battery 

disconnects and computer memory clear events as well as remove the requirement that the new 

parameter directly report whether the last monitoring event was a pass or a fail. 

Our Response: 

We agree with the commenters. Since the manufacturers normally implement the OBD 

requirements using technical guidance from the consensus-based SAE J1979 standard we think it 

is important for our requirements to be compatible with that standard provided that it will meet 

the EPA objective and that it be done for the lowest possible cost. EPA received further input 

from commenters on this issue which slightly revised the suggested language in the comment. 

We are adopting provisions consistent with the input from commenters.26

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

MY 2017 Implementation of “Distance Since Evap Monitoring Decision” As currently written, 

the regulations require, beginning in MY 2017, 100 percent implementation of the OBD distance 

since evap monitoring decision. Implementing even a relatively straightforward requirement 

such as this one, across all vehicles adds burden – in this case, unnecessarily. We do not believe 

it was EPA’s intent to require a 100 percent phase-in of this requirement in MY 2017. Moreover, 

the leak emissions standard does not begin until MY 2018 and then phases in with the Tier 3 

evaporative emissions standards (60/60/80/80/100 percent starting in MY 2018), and the phase in 

for the two should be aligned.

Recommendation: We recommend the following change to §86-1806(b): ‘(b) The following 

additional provisions apply to vehicles that are also certified to the leak emissions standard of 

§86.1813-17(a)(4).’ 

Our Response: 

 

26 Passavant, G. (January, 2014). “Manufacturer Input on Distance Since Last Evaporative Monitoring Decision”. 

Memorandum to the docket.
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EPA concurs with this comment. The “Distance Since Evap Monitoring Decision” 

requirement will be phased in on vehicles as they meet the leak standard. This occurs over the 

2017-2022 or 2018-2022 model years depending on the compliance option used for the 2017 

model year.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

MY 2017 Implementation of California 0.02” Leak Detection Monitor:

The proposed regulation would also drop the option for federal vehicles to comply with an OBD 

leak detection monitor requirement of 0.04” and require all federal vehicles to comply with the 

current California OBD requirements, including the 0.02” evaporative leak detection monitor (in 

lieu of the federal 0.04” leak detection monitor) and rate based monitoring requirements (which 

are not included federally). As proposed, the 0.02” leak detection requirements would be 

required for each manufacturer’s full federal fleet in MY 2017. While several manufacturers 

comply with the California OBD requirements nationwide already, other manufacturers certify a 

large portion of their federal fleet to the federal OBD standards. Validating their entire federal 

fleet to the 0.02” leak detection monitor will involve significant resources and cannot be 

efficiently implemented in the time between the Tier 3 final rule and MY 2017. For example, the 

federal vehicles will need to be validated at high-altitude, a requirement that does not exist in the 

California program. Rather than a 100 percent requirement in MY 2017, we recommend EPA 

provide a phase-in period to allow these manufacturers to more efficiently manage limited 

resources needed to make this conversion. The Tier 3 program already involves a number of 

different phase-in provisions. Creating another phase-in that is not aligned with other provisions 

would add burden on both the manufacturers and the agency in the form of unnecessary new 

reporting and tracking compliance requirements. For simplicity, we recommend linking the 

phase-in of the 0.02” monitor requirement with the percentage phase-in steps that have already 

been proposed for the new evaporative and leak test emission standards. We recognize the 

agency might be reluctant to allow this long phase-in of the basic monitor requirement because 

there may be incremental air quality benefits associated directly with the change from the 0.04” 

to the 0.02” monitor requirement independent of the leak test standard and accompanying OBD 

changes (i.e., distance monitor, etc.). However, we believe there will be enough incentive for 

manufacturers to make this conversion as soon as possible that a separate, more rapid and more 

rigid phase in requirement will be unnecessary. Given that not all manufacturers are in this 

situation (i.e., significant use of the 0.04” option) and given there will be a strong incentive to 

move as quickly as possible to achieve a full national fleet of vehicles that can be sold anywhere 

in the U.S., it seems very unlikely that any manufacturer would take the fullest advantage of the 

phase-in schedule. Use of the 0.04” monitor would prevent a vehicle from becoming a “50-state” 

vehicle. Under the current Tier 2 regulations, there are multiple differences between the EPA and 

California requirements that might cause a manufacturer to opt for separate fleets. But given that 

EPA has worked to align the Tier 3 program as much as possible with the California LEV III 

program, in the future there will be fewer reasons for a manufacturer to opt for separate fleets, 

particularly if the only difference is the OBD leak monitor. Therefore, we don’t think EPA needs 

to add complexity to the program by creating another phase-in that is not aligned with other

aspects of the Tier 3 program.
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Recommendation: We recommend that EPA provide a phase-in for the CA OBD leak detection 

monitor requirements (0.02” detection) that aligns with the phase-in for the leak emissions 

standards (60/60/80/80/100 starting in MY 2018). 

Our Response:

There are very few manufacturers who are not already fully compliant with the 0.020” 

cumulative diameter threshold for leak diameter monitoring on all of its Federal models, even 

though the current Federal requirement is only for a 0.040” cumulative diameter threshold. The 

0.020” threshold has been in effect in California for over ten years. EPA sees no need for a full 

phase-in as requested, but sees the value in giving those manufacturers who are not yet fully 

compliant with the 0.020” threshold some flexibility to integrate the prove-out of their 

monitoring hardware and software with other field work. Therefore, we are providing a very 

limited phase-in flexibility wherein manufacturers may defer 100 percent compliance for their 

gasoline-powered vehicles less than or equal to 14,000 lbs GVWR until the 2018 model year by 

pulling ahead compliance to the 2016 model year for a percentage equal to or greater than that 

percentage that they wish to defer to the 2018 model year.

 

What Commenters Said:

Organization: California Air Resources Board (CARB)

Currently U.S. EPA accepts On-Board Diagnostics (OBD) systems certified to CARB’s OBD II 

regulation as systems also satisfying the federal OBD regulation. The NPRM proposes to codify 

this practice by adoption and incorporation by reference CARB’s OBD II regulation (title 13, 

California Code of Regulations, section 1968.2) as approved on June 17, 2010, effective starting 

in 2017 model year, except for the following provisions:

- sections 1968.2(a), (b), (k) are excluded 

- the tampering clause in section 1968.2(d)(1.4) is excluded

- the camshaft/crankshaft alignment monitoring requirement in section 1968.2(e)(15.2.1)(C) 

would only apply to vehicles with variable valve timing systems 

The proposal also includes a requirement for manufacturers to perform additional demonstration 

testing of the evaporative system monitor capability and to report additional standardized data 

through the OBD system that would identify how many miles since the evaporative system leak 

detection monitor last completed. 

Comment 2 - Camshaft/crankcase Alignment Monitoring Requirement:

The proposal includes a specific exclusion for the requirement in the CARB OBD II regulation 

section 1968.2(e)(15.2.1)(C) that OBD systems must be able to detect a misalignment between 

the crankshaft and camshaft. This is not a technology-forcing requirement and has been in place 

for many years in California-certified OBD II systems. CARB believes that a reduction in 

diagnostic capability and emission benefit would result due to the exclusion of 

camshaft/crankshaft alignment monitors on vehicles without variable valve timing systems, 

because alignment malfunctions can routinely occur in-use due to timing belts slipping or being 
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improperly installed during maintenance involving timing belt replacement. Therefore, CARB 

recommends that the proposed regulation language be changed by removing the specific section 

that limits camshaft/crankshaft alignment monitoring to only those vehicles equipped with 

variable valve timing systems. 

Our Response: 

This limitation is specifically included in the current EPA OBD requirements and EPA 

did not specifically propose to remove it. EPA did not receive input on this issue from any

manufacturer and we did not seek their input on CARB’s comment. Thus, while EPA believes 

CARB’s perspectives have merit, we are not in a position to remove this limitation without input 

from the manufacturers and others. It should be noted that the requirement will continue to 

apply to vehicles equipped with variable valve timing systems and these are expected to become 

more prevalent in response to the 2017-2025 model year GHG and fuel economy standards. 

What Commenters Said:

Organization: California Air Resources Board (CARB)

Comment 3 - Evaporative Leak System Monitor:

The NPRM proposes a requirement for manufacturers to phase-in a 0.020 inch leak detection 

monitor as CARB’s OBD II regulation has required since the 2002 model year. CARB supports 

this change to align detection capability nationwide. Further, most manufacturers already extend 

this capability nationwide by certifying a single system that meets CARB requirements. 

Our Response:

We agree with this commenter. The requirement is feasible and being met by almost all 

manufacturers. The requirement will apply to all 2017 and later model year gasoline-powered 

highway motor vehicles up to 14,000 lbs GVWR. The regulations provide a limited flexibility 

which will permit manufacturers to defer full compliance to the 2018 model year if they comply 

in the 2016 model year with a percentage equal to or greater than the percentage they defer from 

the 2017 model year to the 2018 model year.

What Commenters Said:

Organization: Ford Motor Company (Ford)

Adoption of CARB OBD Regulations: EPA has proposed to require that all Federal vehicles 

meet California’s On-board Diagnostic regulations by the 2017MY. Ford has two specific 

concerns with this proposal:

0.020” OBD Leak Monitor Detection Threshold – This proposal would require that all Federal 

vehicles adopt California’s 0.020” leak detection monitor threshold by the 2017MY. The existing 
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EPA requirement for leak detection is 0.040”, but under the Tier 3 proposal, 100% of a 

manufacturer’s fleet would be required to meet this more stringent requirement in 2017MY. 

Although most Ford vehicles have a leak detection monitor capable of meeting this new 

requirement, they have not been validated to the 0.020” threshold on a nation-wide basis. In 

order to accomplish robust leak detection to the more stringent standard nationally, additional 

validation and data collection must be performed that account for more varied environmental and 

market fuel conditions encountered in all 50 states (e.g., high-altitude, additional fuel 

formulations, etc.). Since OBD assessments are typically performed holistically as part of new 

program vehicle development, the processes and engineering resources are not in place to 

retroactively reassess existing systems to account for these new conditions. For these reasons, 

Ford proposes that EPA allow a phase-in for the 0.020” requirement of sufficient duration to 

allow migration to the new standard to be accomplished via new program development, which is 

typically on a three-year cycle. 

Recommendation: Ford proposes that EPA provide a phase-in for the new 0.020” OBD leak 

detection threshold that would allow Ford to utilize its existing, robust new program OBD 

validation processes and avoids the need to employ ad-hoc, off-program actions. Ford requests 

that such a phase-in start no earlier than 2016MY, and extends for at least three years. 

Our Response:

There are very few manufacturers who are not already fully compliant with the 0.020” 

cumulative diameter threshold for leak diameter monitoring on all of its Federal models, even 

though the current Federal requirement is only for a 0.040” cumulative diameter threshold. The 

0.020” threshold has been in effect in California for over ten years. EPA sees no need for a full 

phase-in as requested, but sees the value in giving those manufacturers who are not yet fully 

compliant with the 0.020” threshold some flexibility to integrate the prove-out of their 

monitoring hardware and software with other field work. Therefore, we are providing a very

limited phase-in flexibility wherein manufacturers may defer 100 percent compliance for their 

gasoline-powered vehicles less than or equal to 14,000 lbs GVWR until the 2018 model year by 

pulling ahead compliance to the 2016 model year for a percentage equal to or greater than that 

percentage that they wish to defer to the 2018 model year.

4.4.3. Provisions for Emergency Vehicles

What Commenters Said:

Organization: Ford Motor Company (Ford)

Emergency Vehicle Provisions:

The CARB OBD regulation required manufacturers to meet unique monitoring requirements to 

detect malfunctions causing an air/fuel ratio imbalance between cylinders. By the 2016 model 

year, all vehicles certified to the CARB OBD II requirements must meet the final Air/Fuel Ratio 

Imbalance Monitor (AFRIM) requirement final emissions threshold of 1.5 times the applicable 

standard. We believe there should be an exemption from the AFRIM threshold for emergency 
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vehicles. We will illustrate this comment with the example of Ford’s 2016 and later model year 

Police Interceptor package. In order to meet the 1.5 times the standard emissions threshold, the 

Police Interceptor would require an added underbody catalyst. This would result in performance 

degradation for the Police Interceptor, with a 0-100 MPH time increase that may not meet police 

agency expectations. As a result, CARB had agreed to provide Ford with an exemption from the 

AFRIM requirement on the Police Interceptor package using a provision in the California 

Vehicle Code that allows emergency vehicles to meet Federal emissions requirements:

27156.2 Notwithstanding any other provision of law, any publicly owned authorized emergency 

vehicle operated by a peace officer, as defined in Section 830 of the Penal Code, any authorized 

emergency vehicle, as defined in Section 165 and used for fighting fires or responding to 

emergency fire calls pursuant to paragraph (2) of subdivision (b) or pursuant to subdivision (c) or 

(d) of that section, and any publicly owned authorized emergency vehicle used by an emergency 

medical technician-paramedic, as defined in Section 1797.84 of the Health and Safety Code, is 

exempt from requirements imposed pursuant to California law and the regulations adopted 

pursuant thereto for motor vehicle pollution control devices.

Ford had planned to certify the 2017 and subsequent model year Police Interceptor without the 

AFRIM monitor since the Federal OBD requirements do not require this monitor. The vehicle 

could then be certified and sold in all 50 states. The Police Interceptor is being developed to meet 

all other Federal and California emissions and OBD requirements. However, EPA’s proposal to 

require CARB OBD II on all Federal vehicles by the 2017 model year would force the Police 

Interceptor to again have to meet the AFRIM requirement, and thus force those vehicles to be 

fitted with an underbody catalyst with the associated vehicle performance reduction for the sole 

purpose of keeping emissions below 1.5 times the standard just in case an unlikely cylinder 

imbalance malfunction were to occur. We do not think it was EPA’s intent to impose OBD 

requirements on Federal vehicles that CARB would not require on vehicles sold in California. 

Recommendation: With respect to the AFRIM issue specifically, Ford recommends that EPA 

provide an exemption from the CARB OBD II AFRIM requirement in 13 CCR 1968.2, 

paragraph (e)(6.2.1)(C) through at least the 2019 model year for emergency vehicles. This would 

allow Ford the sufficient lead time to implement the necessary design changes need to meet the 

CARB OBD II AFRIM requirement without needing to add hardware or other solutions that 

reduce vehicle performance levels. More generally, we encourage EPA to adopt language in the 

final Tier 3 rules to the effect that EPA will recognize and adopt, with respect to Federal 

vehicles, any OBD exemptions that CARB may allow for California vehicles. 

Our Response:

EPA has held follow-up discussions on this matter with Ford and CARB staff and has 

reviewed the technical data regarding the ability of the law enforcement vehicles to meet the 

AFRIM monitoring threshold requirements.27 Adding an underbody catalyst to these two vehicle 

configurations just to meet the AFRIM requirements adds cost and more importantly reduces 

performance needed in these types of vehicles. These two test groups (comprised of law 

 

27 Passavant, G, (January, 2014). Information Related to CARB AFRIM OBD Requirements for Emergency 

Vehicles. Memorandum to the docket.
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enforcement vehicles) are not required to meet the current AFRIM monitoring requirements and 

CARB does not intend to require it in the future. Since Ford expects to have compliant 

powertrains for these test groups by the 2020 model year and the only potential adverse 

environmental effect is failure to notify the user in the event of an AFRIM imbalance situation, 

EPA will defer this requirement for these vehicles through the 2019 model year. The final rule 

also incorporates broader provisions that address potential future OBD issues related to 

emergency vehicles.

4.4.4. Future Considerations

1. OBD Monitoring of the Performance of Canister Carbon

What Commenters Said:

Organization: Revecorp Inc.

Although tailpipe emissions are significant, Revecorp is most concerned with changes in the 

proposed rule related to the control of evaporative emissions. This is because evaporative 

emissions account for 30 to 40% of hydrocarbon emissions, including toxics such as benzene. 

Research conducted for EPA has shown that vehicles can have failures of the evaporative 

emissions control systems (such as deactivation of the canister substrate) that OBDII systems do 

not identify. This is in part because sensing of the activity of the canister carbon is not monitored 

by OBDII systems, so when it fails, it goes unnoticed. This can lead to vehicles with 

uncontrolled evaporative emissions for the life of the vehicle, which is not identified by the 

OBDII system (to notify the motorist to get the vehicle repaired) and not caught by in-use 

compliance testing because it is not required for evaporative emissions control systems (at least 

not at high altitude). 

On-board diagnostic systems should be strengthened to improve identification of in-use excess 

emissions.

As noted above, without a way to identify failures of the emissions control systems in-use, 

vehicles will have high emissions for their lifetimes. In one phase of a study conducted for EPA 

on in-use vehicle evaporative emissions (EPA contract #: EP-C-06080, the “Ken Caryl” phase of 

the study) 50% to 75% of the vehicles which were identified to have high evaporative emissions 

did not have the check engine light illuminated (the excess emissions were not identified by the 

OBDII system). This is in part because a major component of the evaporative emissions control 

system (the evaporative canister) is not checked by the OBDII system to ensure it is functioning 

properly. In some cases, canisters were damaged and evaporative gases were escaping into the 

environment. The canister of a vehicle is the single most important component of the evaporative 

emissions control system and should be monitored to ensure it is performing properly. 

Revecorp recommends – Monitoring of canister performance should be added to the OBDII 

requirements. 
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Our Response: 

EPA agrees that the canister performance is critical to the overall ability of the 

evaporative system to control vapor emissions. While it is easy to estimate the emissions 

increase which occurs if the canister partially or totally fails – and it is quite large- it is more 

difficult to determine the frequency and cause of such failures. Purge valve failures leading to 

saturated canisters are infrequent (~0.5% )28 based on an initial review of OBD data, but the 

frequency of saturated canisters related to other causes such as blocked air inlet purges and 

ingestion of liquid is unknown and is informed only by anecdotal information. EPA is now 

engaged in further study of this question to help determine the frequency of such occurrences 

and whether an OBD requirement is justified.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

OBD monitoring of the performance of the canister carbon is neither necessary nor practical. The 

OBD system currently verifies that the canister is in the system (large and small evaporative leak 

test) and that purge is working correctly. Also, if the system is designed properly so that there is 

no liquid water or fuel entering the canister, the carbon in modern canisters does not deteriorate 

during the life of the vehicle. Therefore, diagnosis of the canister carbon is unwarranted. 

Furthermore, diagnosis of the performance of the carbon would be extremely difficult. The 

potential diagnostic signals associated with vapor in the fuel today, e.g., (closed loop fueling 

feedback) have too much variation to make a reliable diagnostic. Even adding new hardware for 

diagnosis e.g., carbon bed temperature sensor, would not provide for a reliable diagnostic. 

Our Response: 

EPA disagrees with the assessment of the commenter with regard to the technical 

capability to monitor canister performance. If it is warranted, there are several sensing schemes 

which could be used to monitor the in-use performance of the canister itself. However, as 

mentioned above, more information on the frequency and causes of failures is needed, so we are 

not putting a requirement in place at this time.

What Commenters Said:

Organization: California Air Resources Board (CARB)

Comment 4 - Evaporative System Activated Carbon Canister Monitor and Purge Monitor:

 

28 Weatherby, M., Sabisch, M., Kishan, S. (2014) Analysis of Evaporative On-Board Diagnostic (OBD) Readiness 

and DTCs Using I/M Data.
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Though not officially part of U.S. EPA’s proposal, U.S. EPA seeks comments about a provision 

to require the OBD system to monitor the activated carbon canister, specifically for evidence of 

proper performance of the canister such as adequate adsorption and desorption of hydrocarbon 

vapors. U.S. EPA believes such performance could be sensed with existing hardware on the 

vehicle (e.g., looking for changes in canister carbon bed temperature or presence of vapor in the 

fuel going to, the intake manifold after a cold start or refueling event). CARB currently has no 

requirement for monitoring the canister performance but given the increasing importance of 

keeping evaporative emissions to a minimum, believes the idea merits further exploration and 

research before making any decisions on implementing any regulation changes. Important 

aspects that would likely need to be investigated include whether monitoring of the activated 

carbon canister can indeed be robustly done with the existing hardware on the vehicle. 

Our Response: EPA agrees that given the potential emissions impact, this issue merits further 

research and assessment. EPA believes that if monitoring is warranted, there are several sensing 

schemes which could be used to monitor the in-use performance of the canister itself. However, 

as mentioned above, more information on the frequency and causes of failures is needed before 

we propose a requirement. 

2. OBD Monitoring of Vacuum Pump or Other Assist Hardware 

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

If a vacuum pump or other hardware is utilized to assist canister purge, the current OBD 

regulations would require that this pump and associated hardware be monitored. 

Organization: California Air Resources Board (CARB)

Regarding devices used to assist purge flow, increased usage of such devices in the future is 

possible, so further investigation into monitoring of these devices is warranted. However, CARB 

believes the OBD regulation already covers monitoring of these devices to some extent, since 

they would be considered evaporative system components and consequently required to be 

monitored under comprehensive components requirements for proper function. 

Our Response: 

EPA appreciates these comments and will include such monitoring approaches in future 

certification reviews if a future system uses a vacuum pump or other hardware to assist canister 

purge.

3. Diagnose Sealed Fuel Systems Down to 0.010” or 0.015”

What Commenters Said:
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Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Industry is opposed to OBD detection of leaks smaller than 0.020” in sealed fuel systems. Fuel 

system leaks that are less than 0.020” are extremely difficult to detect and are even more difficult 

to repair. Attempting to detect leaks smaller than 0.020” would result in a high risk of false MILs 

and numerous vehicles that could not be repaired. Ultimately, this would undermine the public’s 

confidence in OBD performance. 

Organization: California Air Resources Board (CARB)

EPA also seeks comments about a provision regarding pressurized and sealed fuel tanks. Based 

on its observation of a trend towards fuel tanks with higher operating pressures or tanks sealed to 

the atmosphere during normal operation and data showing a leak in these systems will result in 

substantially higher emissions relative to traditional low pressure systems. U.S. EPA seeks 

comment on the feasibility and cost of requiring OBD leak detection monitors to detect a smaller 

diameter orifice on such systems - specifically, something in the magnitude of a 0.010 inch leak 

in lieu of a 0.020 inch leak anywhere in the evaporative system. This would apply to vehicles 

with a designed in-use operating pressure in excess of 0.36 psi (10 inches of water).

CARB currently has no such requirements but given the increasing importance of keeping 

evaporative emissions to a minimum, believes the ideas merit further exploration and research 

before making any decisions on implementing any regulation changes. Important aspects that 

would likely need to be investigated include the feasibility of the repair service community to 

efficiently diagnose and repair detected leaks with a smaller diameter.

Our Response:

EPA understands the concerns regarding detection and repair raised by the commenter. 

While there is limited data on emission rates as a function of cumulative orifice diameter, more 

information on the frequency of such leaks is needed before pursuing this requirement.

4. Vent Leaking Sealed Fuel Tank System to Canister

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA has requested comment about opening the vent valve on key off if a leak is detected in a 

sealed fuel system. This concept will not reduce the emissions from a leak because the flow 

through the canister is more restrictive than the flow out of the leak. Therefore, almost all of the 

vapor will go out the leak rather than into the canister. 

Organization: California Air Resources Board (CARB)
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For sealed tanks, U.S. EPA seeks comments on an added requirement that any valve that isolates 

the fuel tank vapor from the canister be defaulted to an open position at key off (allowing vapors 

to vent to the canister) if the OBD monitor detects a leak and illuminates the malfunction 

indicator light. Further, for pressurized systems, U.S. EPA is asking for comment on setting the 

evaporative system monitor threshold in the 0.010 inch to 0.015 inch range, specifically asking 

for the feasibility of this threshold, the effects of the vent valve open requirement on on-board 

refueling vapor recovery, and the reparability of leaks below 0.020 inch.

CARB currently has no such requirements but given the increasing importance of keeping 

evaporative emissions to a minimum, believes the ideas merit further exploration and research 

before making any decisions on implementing any regulation changes. Important aspects that 

would likely need to be investigated include the feasibility of the repair service community to 

efficiently diagnose and repair detected leaks with a smaller diameter. 

Our Response:

EPA did not make a specific proposal with regard to venting of higher pressure or sealed 

fuel tanks with leaks to the activated carbon canister. While sealed or higher pressure fuel tank 

system designs are not common today, the reduction of vacuum for purge air in some future 

engines/powertrains (e.g., hybrids) creates the possibility that manufacturers will turn designs of 

this nature to help reduce vapor loads to the canister and thus allow for lower purge volumes. 

Manufacturers should be cognizant of the issue raised by EPA in the NPRM and put emphasis on 

system durability. In coordination with CARB, EPA will continue to evaluate trends in fuel 

system operating pressures and potential design features leading to leaks.

4.4.5. Heavy-duty Vehicles

What Commenters Said:

Organization: Truck and Engine Manufacturers Association (EMA)

OBD Requirements as Applied to Hybrid Applications:

Current ARB and EPA OBD regulations include provisions requiring hybrid components and 

systems to be monitored under “comprehensive component monitoring” requirements. Those 

provisions pose a significant barrier to the introduction of hybrid system technology. In fact, the 

current OBD provisions will substantially limit the availability of hybrid vehicles nationwide. 

The use of hybrids in medium- and heavy-duty commercial applications is an emerging 

technology, and the market for that technology is very small relative to overall heavy-duty 

applications and to the light-duty passenger car industry. There are multiple medium- and heavyduty duty-cycles and applications where hybrids might be practical. Additional time is needed to 

develop and commercialize hybrid technologies for those applications, and even more time and 

resources are needed to develop proper diagnostics on hybrid components. As things stand, 

however, current OBD regulations will result in little or no use of hybrid applications in 

California, depriving the state (and any state that has opted in to California’s standards) of the 
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fuel efficiency and other benefits that hybrid technology has to offer. The same is true 

nationwide, as EPA’s existing hybrid OBD requirements for heavy heavy-duty vehicles and 

engines become fully implemented. Engine and vehicle manufacturers are continuing their 

efforts to assure that hybrid technology – an important GHG emission-reduction opportunity –

will be available throughout California and the remainder of the U.S. EPA should support those 

efforts by adopting (and, as necessary, amending) OBD regulations without hybrid component 

monitoring requirements. EPA should take additional time to assess whether a potential 

regulatory framework can be developed, with appropriate lead time, that assures the feasible, 

cost-effective and reasonable development of hybrid system and engine technologies and 

associated diagnostic strategies. 

Take additional time to assess the appropriate regulatory framework for cost effective and 

feasible development of hybrid technology and diagnostic strategies 

Our Response:

EPA acknowledges EMA’s comment opposing hybrid component monitoring 

requirements. However, no detail regarding the technology issues or problems or systems 

integration was provided in the comment. Follow-up discussion with EMA indicated that their 

major concern regarding OBD and hybrids was related to vehicles over 14,000 lbs GVWR.29

After confirming that the Tier 3 rulemaking does not address OBD requirements for vehicles 

over 14,000 lbs GVWR and that appropriate lead time would be provided for new heavy-duty 

vehicles equal to or less than 14,000 lbs GVWR, EMA was satisfied with the way EPA was 

implementing the OBD requirements for hybrids for vehicles equal to or less than 14,000 lbs 

GVWR. Thus, we are not deferring adoption of OBD requirements as part of the Tier 3 rule. As 

discussed below, the OBD provisions of the Tier 3 rule do not apply to vehicles/engines over 

14,000 lbs GVWR.

14,000 Pounds GVWR and Under:

EPA is proposing to update its OBD regulations to be consistent with ARB’s current OBD 

requirements (“OBDII”). (78 Fed. Reg. at 29903-29904.) For Heavy-Duty Vehicles (8,501-

14,000 GVWR), those requirements would begin in MY2018. Although adopting the OBDII 

regulations for MY2018 does not provide the four full model years’ lead-time required by the 

CAA, EMA recognizes that EPA already accepts certification with ARB OBDII requirements as 

satisfying EPA OBD requirements for vehicles 8,501-14,000 lbs. GVWR. As a result, EMA 

generally supports such alignment with ARB’s OBDII regulations, with the significant exception 

noted above. EPA should support manufacturers’ efforts to assure the cost-effective commercial 

use of hybrid technology by adopting the OBDII regulations without hybrid component 

monitoring requirements. If EPA were to adopt the OBDII provisions without removing such 

requirements, the successful commercialization of hybrid vehicles throughout the nation would 

be substantially impeded, if not thwarted altogether. 

Adopt the ARB’s OBDII regulations without requirements to monitor hybrid components 

 

29 Passavant, G. (February, 2014). “OBD for Hybrid HD Vehicles/Engines”. Memorandum to the docket.
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Our Response:

As discussed above and in the preamble, EPA proposed adoption of CARB 2010 OBD 

regulations and based on comments is adopting the version of the CARB OBD regulations 

completed in July 2013. With the exception of hybrids EMA did not oppose the 2018 model 

year implementation of OBD for HDVs equal to or less than 14,000 lbs GVWR. EMA’s 

comment concerning hybrid component monitoring is addressed above. As discussed in the 

preamble, to be consistent with the manner in which the Tier 3 exhaust emission standards are 

being implemented for the heavy-duty vehicles between 8,501 and 14,000 lbs GVWR, the OBD 

requirements will apply in MY 2019 based on the Job 1 (first production) date for the 

vehicle/engine model. If the vehicle/engine model Job 1 date is before the fourth anniversary 

date of the signature of the Tier 3 rule the Tier 3 requirements will be mandatory in the 2020 

model year, not the 2019 MY. If the Job 1 date is on or after the fourth anniversary of the 

signature date of the Tier 3 rule the OBD requirements will apply beginning in MY 2019. The 

Tier 3 OBD requirements will apply to all 8,501-14,000 lb HDVs beginning in MY 2020.

Over 14,000 Pounds GVWR:

In the preamble to the Proposed Rule, EPA indicates that the proposal to adopt the California 

OBD regulations also “includes heavy-duty vehicles above 14,000 lbs. GVWR, though these 

vehicles would not need to meet the new requirements related to leak testing” (78 Fed. Reg. 98, 

29919). Based on other language in the Proposed Rule, including footnote 313 of the preamble 

(which specifically states, “We are not proposing to change the [OBD] requirement for 

incompletes and vehicles with a GVWR above 14,000 lbs.”) (78 Fed. Reg. at 29904), EMA 

believes the reference on page 29919 of the Federal Register notice is a drafting error. EMA also 

believes the language is an error because EPA has not (1) conducted any technical analysis of 

applying ARB’s heavy-duty OBD regulations; (2) properly notified heavy-duty manufacturers of 

any such significant changes to the EPA heavy-duty OBD program; or (3) proposed any other 

changes in the rule that would require the application of California’s OBD regulations to vehicles 

and engines over 14,000 lbs. GVWR. EPA objects to the finalization of any portion of the 

Proposed Rule that would adopt ARB OBD regulations applicable to vehicles and engines over 

14,000 lbs. GVWR. EPA should clarify in the final rule that no changes to EPA’s on-board 

diagnostics requirements applicable to engines and vehicles over 14,000 lbs. GVWR are being 

proposed or made in conjunction with the Tier 3 Standards (other than OBDII regulations that 

may be applicable to optionally chassis-certified HDGVs). Without this vital clarification, the 

Proposed Rule will be subject to immediate challenge. 

State unequivocally in the final rule that no changes are being made to OBD requirements for 

engines or vehicles greater than 14,000 lbs. GVWR 

Our Response: 

The OBD provisions in this rulemaking do not apply to vehicles/engines over 14,000 lbs 

GVWR, except that the Tier 3 OBD regulations are applicable to optionally chassis-certified 

HDGVs.
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4.4.6. Other Issues

What Commenters Said:

Organization: VNG.CO

Reduced OBD Testing Requirements – Today: Current EPA rules allow alternative fuel 

conversion SVMs to meet much less stringent OBD requirements than OEMs certifying small 

volume test groups, with as few as four tests of major diagnostic monitors (including fuel trim 

lean & rich, catalyst deterioration, engine misfire, and oxygen sensor) instead of the many more 

typically required for OEM certification.15 As illustrated above, the NPC Future Transportation 

Fuels report notes that “certification, OBD, aftertreatment and calibration” are a significant 

source of per-vehicle incremental costs for current OEM NGV production. This is particularly 

the case for pickup trucks, where it is the single largest cost component at about $4,500 per 

vehicle, or nearly 40% of the total incremental cost.16 Harmonizing OEM small vehicle test 

group OBD testing procedures with the reduced OBD testing requirements for alternative fuel 

converters is consistent with the ‘level playing field’ provided in most other respects between 

these categories of vehicles, and represents a major opportunity to reduce NGV incremental costs 

for consumers without sacrificing the efficacy of the certification process.17 Reduced OBD 

Testing Requirements – Under Tier 3: The Tier 3 NPRM proposes that EPA “upgrade” its OBD 

regulations “to be consistent with the latest CARB regulations.” These CARB OBD 

requirements are similar to the EPA requirements for full OEM testing and have similarly been 

cited as “the most costly and time-consuming requirement in the certification process” for NGV 

aftermarket conversions in the California market.19 Compared to the streamlined EPA OBD 

testing requirements for SVM converters, which usually require a handful of demonstrations that 

can be reviewed in a week, the CARB process currently requires “more monitors to be adjusted, 

more tests for each of these monitors to be conducted, lots of documentation on the adjustments 

to monitors, and many more test results to be reported,” resulting in application packages of 200-

300 pages long that take CARB about 3 months to review.20 This adds considerable expense as 

well as time to the certification process, and this barrier to entry has limited the availability of 

NGV conversions in California. 

For this reason, CARB is working with stakeholders to develop less extensive OBD testing 

requirements for small-volume converters that will be aligned with EPA SVM requirements 

while still ensuring effective emissions performance. Similar to EPA’s rules for SVM converters, 

the new CARB rules would require as little as four demonstrations of OBD systems. 21 

Consistent with EPA’s judgment in allowing reduced OBD test requirements for converters, 

CARB notes that this reduced testing burden will still preserve emissions benefits of their 

emissions program. EPA should ensure that the Tier 3 rules incorporate these and other changes 

that CARB makes to streamline its own regulations. 

CARB’s proposed rule changes will significantly reduce barriers to entry in California; however, 

like the current EPA OBD rules, they apply only to aftermarket converters. In order to 

effectively harmonize these rules with existing EPA definitions as well as to provide a level 
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playing field between SVMs and OEM small-volume test groups, the Tier 3 rules should specify 

that any reduced aftermarket OBD requirements introduced by CARB will be applicable to OEM 

small-volume test groups as well as SVM converters up to the current 15,000 vehicle thresholds 

for each. 

Our Response: 

EPA met with the commenter in October 2013 to get a better understanding of the issues 

raised in their comments.30 EPA proposed that the new OBD provisions not apply to the small 

businesses and SVMs (as defined in the rule) until the 2022 model year. Provisions for OEM 

small volume test groups were not included. We understand the commenter’s view that OBD is 

potentially more costly for small volume test groups and could be a deterrent to a manufacturer 

decision to develop these configurations. EPA is willing to consider reduced OBD requirements 

for small volume test groups of OEMs (perhaps on a transitional or interim basis). However, 

EPA cannot before the fact commit to applying the changes under consideration in California.

Commenters’ footnotes:

15 Environmental Protection Agency. “Clean Alternative Fuel Vehicle and Engine Conversions Final 

Rule: Webinar for Conversion Manufacturers.” 27 April 2011. 

http://www.epa.gov/otaq/consumer/fuels/altfuels/conversions-fr-webinar.pdf 

16 National Petroleum Council. “Future Transportation Fuels: Natural Gas Analysis.” 28 May 2013. pp. 

53-58. http://www.npc.org/FTF-report-080112/Chapter_14-Natural_Gas-052813.pdf

17 Existing EPA regulations (40 CFR 86.1806–01) already afford flexibility in OBD testing requirements 

and allow EPA to reduce them if requested to do so by the applicant, particularly in the case of alternative 

fuel vehicles. EPA should encourage both SVM converters and OEMs certifying NGVs in small-volume 

test groups to request and utilize these reduced OBD requirements.

18 Environmental Protection Agency. “Control of Air Pollution From Motor Vehicles: Tier 3 Motor 

Vehicle Emission and Fuel Standards; Proposed Rule.” Federal Register, 21 May 2013, p. 29903.

19 Ward, Peter F, on behalf of Alternative Fuels Advocates LLC. Letter to Annette Hebert, Chief Mobile 

Source Operations Division, California Air Resources Board. 22 Feb 2013.

20 Carmichael, Tim, on behalf of California Natural Gas Vehicle Coalition. Letter to Annette Hebert, 

Chief Mobile Source Operations Division, California Air Resources Board. 8 Mar 2013.

21 California Air Resources Board. “Public Workshop: Proposed Amendments to the Alternative Fuel 

Conversion Certification Procedures for New and In-Use Vehicles and Engine.” 1 May 2013. 

http://www.arb.ca.gov/msprog/onroad/altfuelconv/5-1-2013_Alt%20Fuels%20Wkshp%20V8.pdf 

4.4.7 Requirements for Alternative Fuel Vehicle Converters

What Commenters Said:

Organization: National Propane Gas Association (NPGA) 

EPA is seeking changes to its regulations that address fuel specifications for gasoline and vehicle 

emission standards for certain types of vehicles. The changes would essentially harmonize 

EPA’s regulations with those of the California Air Resources Board’s (CARB) Low Emission 

 

30 Passavant, G. (October, 2013). EPA and VNG.CO Meeting on Tier 3 NPRM. Memorandum to the docket.
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Vehicle III (LEV III) program. Implementation would be phased-in over a period of time 

beginning from the year 2017 and running thru 2025.

From a broader perspective, NPGA disagrees with the basic premise that EPA should seek to 

harmonize its regulations with the CARB LEV III program. NPGA does agree with EPA’s stated 

intention of allowing manufacturers to be able to sell their product in all 50 states. However, 

NPGA argues that the reverse should occur, i.e. CARB should harmonize its regulations with the 

federal regulations.

CARB’s regulations are typically more stringent than EPA’s, and it’s unclear as to whether all of 

their changes over the years have met the level of administrative approval required by EPA. 

What is clear, though, is the higher costs to certify to CARB’s regulations, which have served as 

a major deterrent for alternative fuel converters to make a business case for participation in the 

California market. EPA has even acknowledged that there is a significant cost burden to comply 

with CARB’s OBD requirements, for example. As a result, can an economic justification be 

made (by CARB or EPA within this NPRM) for the emissions benefits lost due to this cost 

avoidance? 

NPGA believes there is no demonstrated benefit (costs or otherwise) to using CARB’s 

regulations over EPA’s regulations. CARB’s regulations pertaining to alternative fuels have not 

been updated since the 1990s. While NPGA understands they are working on changes to the 

regulations, those changes remain in development and have yet to be finalized. NPGA simply 

believes that EPA’s alternative fuel regulations are easier to manage from a cost/benefit 

perspective compared to CARB’s. 

In 2011, NPGA lauded EPA for promulgating a series of changes that streamlined the 

regulations for certifying alternative-fueled vehicles. This action was a culmination of years of 

effort on the part of both the alternative-fuel industry and EPA in recognition that such changes 

would increase the availability of clean-burning vehicles, and, thus, have the effect of reducing 

pollution. These changes have had an overall positive impact on the industry and 

environmentally, as well, since that time. 

NPGA would caution EPA to be mindful of changes to its emission regulations that would result 

in more conventional fueled vehicles put into operation than alternative fueled vehicles (as has 

occurred in California). Similarly, any changes put in place should not offset the gains in 

pollution reduction from EPA’s 2011 rulemaking that has resulted in more alternative-fueled 

vehicle certifications. 

Our Response:

EPA acknowledges the NGPA comment regarding the value and wisdom of harmonized 

programs and their view that CARB should harmonize with EPA. We are sensitive to this 

concern, but the overwhelming sense of the commenters was that an EPA Tier 3 program 

harmonized with the CARB LEV III program was superior to separate requirements whenever 

possible. EPA agrees with those commenters who supported a harmonized program to the 

greatest degree possible. However, there are a few places where the programs are not fully 
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harmonized and the OBD requirements for alternative fuel converters are one of these situations. 

The thrust of the commenters concerns related to OBD seemed to be that EPA was adopting 

CARBs requirements including those for OBD for alternative fuel converters. This is not the 

case. EPA adopted small alternative fuel converter provisions in 2011 and the converters will 

still be able to meet the OBD requirements using the provisions of 40 CFR 85 Subpart F. We are 

aware of the work ongoing at CARB, but it is not yet final.31 As CARB updates its OBD 

regulations in the future EPA will consider these changes and propose to adopt them, if 

appropriate.

4.5. Emissions Test Fuel (“Cert Fuel”)

4.5.1. Proposed Changes to Gasoline Emissions Test Fuel

4.5.1.1. Ethanol Content of Emissions Test Fuel

What Commenters Said:

Organization: Advanced Biofuels Association (ABFA)

ABFA is an advocate for “Technology Neutrality” throughout the regulatory system and believes 

that biofuels should be allowed to compete freely in the market. Most of the fuel and fuel 

additive regulatory system at US EPA Office of Transportation Air Quality (OTAQ) over the 

years has been written to address the market of the first generation biofuel, ethanol, which has 

been the only cost effective widely available biofuel. Ethanol has been and will continue to be a 

valuable commercial product for the nation’s fuel supply and energy independence. However, 

new biofuel molecules are beginning to enter the market for blending with gasoline. New 

biofuels under development by ABFA member companies and others provide multiple 

commercial and societal benefits such as high energy density, low RVP and improved emissions 

parameters. In addition, many of these fuels would not require any new infrastructure 

investments to reach the market and grow into a significant contributor to the nation’s energy 

independence. 

EPA requests comment on proposing to change the certification test fuel to E15 and supports this 

by stating that the requirements in the Renewable Fuel Standard (RFS-2) will reflect E15 as the 

fuel in the US marketplace in the next 10-15 years. (78 Federal Register 98, 29909). This 

statement is driving towards a specific molecule and is picking winners and losers in the 

marketplace. The RFS-2 requires that the US fuel supply contain 36 billion gallons of renewable 

fuel by 2022 which can be achieved by drop in molecules with more energy density. When the 

RFS-2 was created in 2007, fuel consumption in the US was rising, the NHSTA efficiency 

standards had not been promulgated, and the US government had great hope for the consumer 

acceptance of E85. Since 2007, fuel consumption in the US has decreased significantly and will 

continue to decrease based on CAFÉ standards and other factors. E85 consumption reached 38.6 

million gallons in 2011 and consumption has remained flat since then. This change to the EPA 

 

31 See http://www.arb.ca.gov/regact/2013/altfuel2013/altfuel2013.htm downloaded on February 19, 2014 for more 

information.
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certification test fuel will not achieve the RFS-2 requirements. US EPA creating a technology 

neutral position and allowing the marketplace to pick the winners is the correct approach. This is 

working today, through the higher RIN values driving the market to work with more energy 

dense fuel to fill the based D6 RIN pool. 

In addition, concern for the implications of this rule with respect to vehicle certification, ABFA’s 

concerns with proposed changes in the certification test fuel extend particularly to the use of this 

same fuel as the baseline for Part 79 fuel and fuel additive registration. 

EPA requests comment on a plan to allow the use of E10 as the certification test fuel with a 

transition scheme to E15 in the future. (78 Federal Register 98, 29910) would create confusion in 

the marketplace by changing the base fuel for Part 79 registration. Advanced biofuel companies 

are working to gain the data set to provide to US EPA to register their fuels for on road use. The 

change in base fuel will add extra costs, through further toxicity testing and research to comply 

with Tier I and Tier II requirements, without adding value to the companies or environmental 

benefits. The base fuel should remain a non additive fuel without oxygen to allow for the least 

regulatory burden for todays and future fuel/engine company complying with the US EPA 

regulatory requirements. 

Many companies have already invested significant sums in research and development, facility 

citing, engineering design, or equipment purchase. Of particular concern to ABFA is what signal 

granting a specific molecule for certification fuel will have on the RFS and would have on the 

plans to begin breaking ground on a number of advanced biofuels plants. Several ABFA member 

companies, including Dynamic Fuels, Neste Oil, KiOR, Gevo, Lanzatech, UOP, Solazyme and 

others have already made significant capital investments to build these production facilities that 

are up and running at a commercial scale today. Our regulations need to stay technology neutral 

to provide a marketplace that has not pre-picked the winners and losers. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Automakers support updating certification test fuels in Tier 3 regulations, as California did in its 

recent LEV III rulemaking. 

Automakers support updating and expanding Federal Certification Test Fuels (hereafter “test 

fuels”). We advocate that EPA’s final rule implement a Tier 3 E10 9 psi RVP test fuel as the 

gasoline test fuel (18) rather than an E15 test fuel. There are only about 20 U.S. retail outlets for 

E15 to date, and there are numerous other uncertainties affecting E15 fuel use. Trying to be 

“forward looking” by assuming significant national market penetration of E15 is too speculative 

a basis to require that E15 be the federal test fuel for 2017 and beyond. 

EPA should make the final Tier 3 gasoline test fuel E10 9 psi RVP. 

Organization: Mercedes-Benz USA, LLC on behalf of Daimler AG
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The primary factors which directly impact the Mercedes-Benz GHG Compliance Plan are sulfur 

content in market fuel, and ethanol content and octane level in certification and market fuel. 

Organization: American Coalition for Ethanol (ACE)

Ethanol content - We strongly support EPA’s proposal that emissions test fuel, which is also 

commonly referred to as ‘certification fuel,’ needs to be updated to account for the present-day 

reality that the most popular in-use fuel in the U.S. (E10) contains ethanol, and under the RFS, 

higher blends of ethanol, including but not limited to E15, will become the rule and not the 

exception. 

Indolene, the current certification fuel, is not and never has been useful in the practical sense 

because motorists never used it in vehicles. Updating the federal emission test fuel to better 

match today’s in-use fuel and to reflect the reality that the RFS will call for an ever-increasing 

level of ethanol in gasoline is the appropriate step to take. We strongly support E15 as the new 

certification fuel, and suggest that if a phased-in process is chosen, it be done in such a way that 

it provides incentives for manufacturers that chose to optimize for E15 at an earlier date. 

What is critical is that the certification fuel no longer act as an implicit impediment to higher 

ethanol blends. We expect ethanol blends to increase from E15 to even higher level blends to 

capture the economic value and clean air benefits associated with these higher-level blends. As a 

result, it is critical that EPA institute a certification fuel regimen that is easily adaptable to higher 

level blends. 

Organization: American Fuel & Petrochemical Manufacturers (AFPM)

The AFPM supports a new certification fuel. Indolene should be replaced with E10, not E15.

Almost all gasoline today is E10. It is speculative to expect that E15 will be the predominant 

fuel in 2017. The current certification fuel in California is E10, and one of the stated goals of 

this proposal is harmonization with California standards.

Organization: American Honda Motor Co., Inc.

Testing on E15:

EPA is proposing that E15 become the standard test fuel based upon, for example, anticipated 

market acceptance, the continued implementation of RFS, and the adoption of this standard by 

the retailing industry. While it is true that EPA has approved E15 for use in newer vehicles, this 

highly controversial decision has seen numerous detractors. Furthermore, the RFS could be 

implemented in any number of ways, including: a) a higher percentage of E85 in the market, 

combined with E10, or b) a higher percentage of drop-in biofuels in the market, combined with 

E10, and/or higher E85 sales. Test fuel should represent the market, not forecast the market. 

Additionally, Test fuel should be harmonized as much as possible with California – one of the 

overriding goals of the regulation. We believe it is premature and inappropriate to require as the 

test fuel a market fuel which is, for all intents and purposes, not in the market today. We 

recognize that E10 is the standard fuel in the market today, and believe it would be reasonable 

and appropriate to make E10 the standard fuel for Tier 3. We also recommend that EPA adopt an 
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approach to handle the period in which market fuels are in transition. For example, if and when 

E15 becomes more than 1/3rd (one-third) of all gasoline sales, then EPA will adjust the Tier 3 

rules and adopt the fuel with appropriate phase-in testing requirements. Perhaps EPA is overcorrecting for a previous, perceived error. E10 was a common market fuel available at the time 

of Tier 2, and yet E0 remained the test fuel. It is counter to EPA’s prior practice to require E15, 

an anticipated – but in no way certain – market fuel, to become its new, de facto standard. 

Organization: American Lung Association

Update Certification fuel to in-use fuel. In separate decisions announced in October of 2010 and 

January in 2011, EPA granted a waiver request to major manufacturers of ethanol to increase the 

allowable limit of ethanol in gasoline to 15 percent starting for vehicle model years 2001 and 

after. Although EPA has increased the permissible amount of ethanol in gasoline to 15 percent, 

this fuel is still not widely available in the marketplace. Most gasoline sold today contains up to 

10 percent ethanol by volume (E10). We believe that the certification fuel should match the fuel 

being sold in the market. Based on current gasoline sales, E10 should be the certification fuel. 

We urge EPA to adopt an approach that gives the agency the flexibility to update and match the 

certification fuel with the current market fuel without further rulemaking. Under such an 

approach, perhaps a triggering event such as the suggested 30 percent market share of gasoline 

sold with fifteen percent ethanol (E15), could prompt EPA to change the certification fuel. Two 

model years of lead time for such a switch should be sufficient time for the auto manufacturers to 

accommodate any such change. EPA should continue to have flexibility to make modifications to 

certification fuel specifications as appropriate. 

Organization: American Motorcyclist Association (AMA)

Changing the certification fuel to E15 or E30 is at odds with the 22 million motorcycles and allterrain vehicles currently in use, not to mention the legacy fleet of cars, boats, lawnmowers, 

generators and hundreds of millions of small engines in commerce today. None, of these vehicles 

and engines is designed to operate on fuel with more than 10 percent ethanol. 

Automobile and motorcycle manufacturers must certify that on-highway vehicles produced will 

meet applicable U.S . Environmental Protection Agency and National Highway Traffic Safety 

Administration emissions, fuel economy and safety requirements prior to selling vehicles. The 

fuel vehicles must use for this requirement is called the certification fuel. The current 

certification fuel is E0 - that is, fuel that has no ethanol content. 

The current certification fuel should not be changed to reflect ‘forward-looking’ assumptions 

about what ‘could become a major gasoline blend over the next 10-15 years,’ such as E15 or 

E30. These changes would be contrary to both the letter and spirit of the law. 

Currently, the risks of increasing E15 in the marketplace will negatively impact every American. 

Since the EPA used only one test to determine whether E15 is safe for vehicles before granting a 

waiver, the AMA urges the agency to allow for an independent scientific study of E15. We also 

request that motorcycles and ATVs be included in the study. 
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The AMA has expressed concerns about E15 being mistakenly used and damaging engines in 

motorcycles and ATVs, and about the continued availability of gasoline that has no ethanol, or 

gasoline with only a 10 percent blend, that is safe for use in motorcycles and ATVs. 

Organization: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

Certification Fuel Recommendations:

EPA proposes to change the ethanol content of the gasoline certification test fuel from 0% (E0) 

to 15% (E15) by volume. The certification fuel should be representative of a gasoline/ethanol 

blend that is currently prevalent in the market place; that fuel is one which contains 10% ethanol 

(E10) by volume. 

EPA does not state its legal basis for designating test fuels, and incorrectly asserts sweeping 

discretion under the statute. EPA makes the forward-looking prediction that the Renewable Fuels 

Standard will lead to an expansion of E15, despite the limited commercial availability of the fuel 

today. EPA needs to set certification fuel standards that reflect current driving conditions, and 

the Agency would be in violation of the Clean Air Act if it specifies an ethanol content above 

10% for gasoline certification fuel. 

Emissions certification fuel:

EPA proposes to change the gasoline test fuel for light-duty and heavy-duty vehicles from E0 

fuel to E15 fuel. 78 Fed. Reg. at 29825. EPA does not state its legal basis for designating test 

fuels, and instead asserts in a conclusory way that “we believe we have discretion under the 

statute to transition from E0 to E15 test fuel....” Id. at 29910. 

EPA presents essentially no factual basis for this proposed change to E15. According to EPA, 

“[i]n-use gasoline has changed considerably since EPA’s fuel specifications for emissions testing 

of light- and heavy-duty gasoline vehicles were last set and first revised.” Id. at 29908. EPA 

predicts that the second iteration of the federal renewable fuels standard program (“RFS2”) will 

lead to further changes in in-use fuel, including “expansion of the number of retailers that offer 

E15.” Id. In response to changes in in-use fuel that EPA alleges have already occurred, as well as 

“forward-looking” predictions about the ethanol and sulfur content of future in-use fuels, EPA 

proposes to update the gasoline test fuel provisions of 40 C.F.R. § 1065.710. Id. EPA proposes to 

make this change despite its admission that “E15 is only commercially available at a limited 

number of fuel retailers” at present. Id. at 29909. EPA’s prediction about increased E15 fuel 

availability in the future is premised on “instability in crude oil pricing and growing RFS2 

renewable fuel requirements.” Id. 

EPA seeks comment on its proposed approach of changing the test fuel from E0 to E15, 

including the “forward-looking nature” of this proposal. Id. at 29910. Additionally, EPA seeks 

comment on potential alternative approaches, including designation of E10 as the test fuel and 

later “transition[] to E15 as the market further transitions to E15 in use.” Id. 

EPA should specify E10 as the certification fuel. The CAA requires EPA “to insure that vehicles 

are tested under circumstances which reflect the actual current driving conditions under which 
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motor vehicles are used, including conditions relating to fuel, temperature, acceleration, and 

altitude.” CAA § 206(h). Accordingly, test fuels must “reflect current driving conditions.” Id. 

(emphasis added). 

In keeping with this clear statutory requirement, we agree with EPA that the certification fuel 

should be switched to an ethanol containing blend because ethanol blends are the most prevalent 

type of gasoline currently in the market place. However, we disagree with the proposed selection 

of E15. As was stated in the RIA, most gasoline in the United States contains 10% ethanol by 

volume. The certification fuel should represent the most common grade of fuel sold, which is 

E10. 

We disagree with EPA’s proposal to select a fuel that is “forward looking with respect to the 

maximum gasoline ethanol concentration Tier 3 vehicles could expect to encounter.” Id. This 

creates two fundamental legal problems. 

First, establishing a “forward looking” test fuel violates the statute because a “forward looking” 

fuel such as E15 does not accurately or reasonably reflect the “current” fuels used by affected 

vehicles. The plain language of the statute does not permit EPA to substitute the phrase “forward 

looking” for “current.” EPA’s own analysis shows that E10 is the most prevalent ethanol blend 

in the market today. Thus, E10 is the only ethanol blend that may be specified as a test fuel at 

this time. 

Second, even if the statute could be construed (arguendo) as authorizing EPA to set a “forward 

looking” test fuel, EPA has not put forward adequate factual justification to do so in this case. 

EPA’s proposed “forward looking” E15 test fuel is based on the assertion that E15 “could 

become a major gasoline blend over the next 10-15 years.” Id. at 29909. However, there are no 

data or analyses in the proposal or underlying record that support this prediction. Absent such 

factual support, adopting E15 as a test fuel would be arbitrary and capricious. 

Notably, even if the Agency attempted to assemble factual justification for a “forward looking” 

E15 test fuel, it could not do so. Given the lack of announced E15 compatible vehicles, 

automobile manufacturer warranty statements, lack of refueling infrastructure and the 15 to 18 

year timeframe to turn over the vehicle fleet, E10 will continue to reflect “current driving 

conditions” over the timeframe under consideration by EPA. 

In light of these problems, the only legally-viable course would be to select E10 as the 

certification fuel and transition to E15 if and when E15 become the most prevalent fuel in the 

market. We support a market review at some point in the future after 2017 to gauge E15 usage 

and growth projections. This review could coincide with the technology review for the CAFE 

standards. The certification fuel should not switch to E15 until it becomes the dominant fuel in 

the marketplace. 

Lastly, if EPA ultimately decides to switch to E15, that switch must be accomplished through 

notice and comment rulemaking. EPA suggests in the proposal that such a switch might be 

accomplished automatically in the future by establishing “a “trigger point” (e.g., 30 percent of 

gasoline is E15) in the Tier 3 final rule to prompt an automatic move to E15 after a certain period 
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of time, e.g., two or three years.” Id. at 29910. EPA alternatively suggests that it “could simply 

set a future date (e.g., 2020) with sufficient time for transitioning to E15 test fuel.” Id. Neither of 

these approaches is legally viable. 

Switching to E15 based on a 30% trigger would require a future factual determination that the 

30% trigger has been exceeded. Such a determination constitutes “factual data” that must be set 

out in a proposed rule before EPA may take a final action based on those data. CAA § 307(d)(3). 

Switching to E15 at a fixed point in the future based on a current prediction of when E15 will 

become the prevalent fuel is problematic because, as explained above, EPA has not set out 

sufficient data or analyses to justify a prediction as to when E15 might become the most 

prevalent gasoline. Thus, the only viable way to establish E15 as a test fuel is to do so through 

notice and comment rulemaking at the point when E15 become the prevalent ethanol blend in the 

market. 

EPA proposes to increase ethanol content from zero to 15 volume percent. EPA believes that this 

level is forward-looking with respect to the maximum gasoline ethanol content Tier 3 vehicles 

could expect to encounter. Concerns with vehicle fuel system compatibility still need to be 

addressed in advance of its introduction into commerce. This level of ethanol is also not aligned 

with CARB LEV III test fuel which is set at 10 volume percent. To ensure the most effective 

evaporative emissions control system for in-use operation we would suggest that EPA considers 

setting the ethanol content at 10 volume percent and then adjusting the RVP requirement of the 

certification fuel to account for the allowed 1 psi waiver. Only until vehicle manufacturers all 

warrant their vehicles for E15, and E15 represents a dominant portion of the overall market 

(including California) would it would be appropriate for EPA to consider shifting to an E15 

certification fuel while ensuring no loss of effectiveness of the emission control systems. 

EPA has failed to explain the legal basis for its test fuel proposal. EPA asserts that the primary 

legal authorities for the proposed rule are CAA §§ 202, 206, and 211. 78 Fed. Reg. at 29828-29. 

EPA rulemaking pursuant to these provisions is subject to the requirements of CAA § 307(d). 

See § 307(d)(1)(E), and (K). Pursuant to § 307(d)(3), EPA is required to include in the proposal 

the “statement of its basis and purpose” for the action, which must include “the major legal 

interpretations ... underlying the proposed rule.” 

Yet, EPA does not include any discussion in the proposal of the legal basis for the proposed test 

fuel provisions. For example, there is no explanation of what section or sections of the statute 

authorize it to designate a new test fuel. Similarly, there is no discussion of the scope and extent 

of the Agency’s authority to establish test fuels and specify particular parameters that such fuels 

must meet. The Agency simply asserts that “we believe we have discretion under the statute to 

transition from E0 to E15 test fuel.” 78 Fed. Reg. at 29910. 

Because EPA has not provided any explanation of the statutory authority on which it relies for 

the proposed test fuel provisions, API has no opportunity to comment on that key issue and any 

rule promulgated would be contrary to the Clean Air Act and unlawful. To try and resolve this 

problem, EPA must re-propose the rule to provide an opportunity to comment on the Agency’s 

legal basis for designating a new gasoline test fuel. 
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EPA has failed to consider fully the CAA § 211(f) implications of its test fuel proposal. Section 

211(f) limits the fuels and fuel additives that a manufacturer may lawfully “introduce into 

commerce, or [] increase the concentration in use of.” Pursuant to § 211(f)(1) and (2), only those 

fuels and fuel additives that are “substantially similar to any fuel or fuel additive utilized in the 

certification of any model year 1975, or subsequent model year, vehicle or engine under section 

[206 of the CAA]” may enter commerce for general use in light duty vehicles, or for use by any 

person in any motor vehicles, manufactured model year 1974 or later. (Emphasis added.) EPA 

may grant a § 211(f)(4) waiver from these commercial limitations if the requested waiver “will 

not cause or contribute to a failure of any emission control device or system (over the useful life 

of the motor vehicle, motor vehicle engine, nonroad engine or nonroad vehicle in which such 

device or system is used) to achieve compliance by the vehicle or engine with the emission 

standards with respect to which it has been certified under pursuant to sections [206 and 

213(a)].” 

As EPA explains in the preamble to the proposed rule, pursuant to § 211(f)(4), EPA granted a 

partial waiver for use of E15 by light-duty vehicles model year 2007 and later, and then extended 

the waiver to include model year 2001-2006 light-duty vehicles. 78 Fed. Reg. at 29909 n. 320 

(citing 75 Fed. Reg. 68094 (Nov. 4, 2010) and 76 Fed. Reg. 4662 (Jan. 26, 2011)); see also id. at 

29911. EPA also concluded at the time that E10 was not a certification fuel for purposes of 

determining whether mid-level blends could be put into commerce under the authority of § 

211(f)(1) (under a “substantially similar” determination) rather than pursuant to a waiver issued 

under § 211(f)(4). 75 Fed. Reg. at 68143. In issuing those partial waivers, EPA placed conditions 

designed to, among other things, minimize potential misfueling. EPA complemented those 

conditions through a later rule, known as the “E15 Misfueling Mitigation Measures Rule,” which 

included misfueling prohibition, fuel pump labeling, PTDs, and ongoing implementation survey 

requirements as a “direct and efficient way to further reduce the potential for misfueling and the 

emission increases that would result from misfueling.” 76 Fed. Reg. 44406, 44411 (July 25, 

2011) (emphasis added); see also 78 Fed. Reg. at 29911. EPA stated that these additional 

requirements were directed to “E15 that is introduced into commerce in accordance with the 

partial waivers” and thereby operated “collectively and in tandem with the partial waiver 

conditions [to] maximize the likelihood that E15 is used only in motor vehicles covered by the 

partial waivers and minimize the potential for emissions increases that might otherwise occur.” 

Id. (emphasis added). 

EPA proposes to establish E15 as a certification fuel for purposes of implementing the Tier 3 

standards. This raises two legal issues that EPA has failed to address in the proposal: (1) will 

establishing E15 as a certification fuel authorize E15 to be put into commerce pursuant to § 

211(f)(1); and (2) if so, what effect does this have on the previously-issued E15 partial waivers 

and corresponding misfueling mitigation rule? EPA’s failure to address these key questions 

violates its rulemaking obligations under § 307(d)(3) and renders the proposed rule arbitrary and 

capricious due to the Agency’s failure to identify and address key policy and legal implications 

of designating E15 as a certification rule. 

On the question of whether establishing E15 as a certification fuel authorizes E15 to be put into 

commerce pursuant to § 211(f)(1), language in the preamble seems to suggest that in EPA’s 

view, once EPA designates E15 as a test fuel under § 206, E15 could be introduced into 
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commerce only for the vehicle type(s) for which E15 were specifically authorized for use as a 

test fuel. For example, manufacturers could introduce into commerce E15 for use into heavyduty vehicles without a § 211(f)(4) waiver “[i]f . . . new heavy-duty gasoline vehicles or engines 

begin testing on E15 for certification.” 78 Fed. Reg. at 29911. Under this implied legal analysis, 

commenters are left to guess about many key aspects of this important issue. For example, does 

EPA believe this is how the statute must be interpreted? If not, what other interpretations did 

EPA consider and why were alternative interpretations rejected? 

For example, some might suggest that, under Section § 211(f)(1), if E15 were designated a new § 

206 test fuel, E15 could be introduced into commerce for use in any vehicle without a § 211(f)(4) 

waiver. This view might be supported by the assertion that Section 211(f)(1) does not appear to 

place any limitation on the vehicle types for which a fuel can be introduced into commerce once 

that fuel is designated as a test fuel under § 206. Therefore, assuming arguendo that E15 were 

designated as a test fuel only for light-duty vehicles, it could still be introduced into commerce as 

a fuel for use in any vehicle under § 211(f)(1). We would view such an approach as not 

authorized by the Clean Air Act and therefore unlawful, yet, EPA does not explain how the 

sweeping language of § 211(f)(1) can or should be construed as being as highly constrained as it 

appears to suggest. Thus, EPA’s treatment of this key issue falls far short of the Agency’s § 

307(d)(3) obligation to clearly set out “the major legal interpretations and policy considerations 

underlying the proposed rule.” 

As importantly, EPA also essentially failed to explore the obvious and important implications of 

introducing E15 into commerce under § 211(f)(1) with regard to the previously-issued E15 

partial waivers and misfueling mitigation rule. For example, if E15 may be put into commerce 

under § 211(f)(1), do the previously-issued E15 partial waivers continue to have relevance, 

meaning, or legal applicability? Would the waivers essentially be rendered moot (if E15 may be 

introduced into commerce under § 211(f)(1) by virtue of E15 becoming a certification fuel), and 

does EPA have authority to limit the types of engines/vehicles that may use E15, as it did under 

§ 211(f)(4) by issuing the so-called “partial waivers”? Similarly, does the misfueling mitigation 

rule have any force or effect, given that it was issued for purposes of facilitating implementation 

of the E15 partial waivers? If it does remain in effect, is the misfueling mitigation rule adequate 

given that it was designed to be implemented in conjunction with the misfueling mitigation 

measures required to be implemented as a condition of using the E15 partial waivers? These are 

just a few examples of the many important questions that arise by virtue of designating E15 as a 

certification fuel. 

We certainly reserve our ability to challenge each and every one of these issues and the most that 

EPA says on these important issues is in its discussion of the potential use of E15 in heavy-duty 

vehicles, where the Agency notes that the potential for misfueling in heavy-duty vehicles would 

be addressed in a future action. 78 Fed. Reg. at 29911. Thus, EPA’s treatment of this key issue 

falls far short of the Agency’s § 307(d)(3) obligation to clearly set out “the major legal 

interpretations and policy considerations underlying the proposed rule.” As a result, EPA must 

re-propose the rule and set forth a clear interpretation of §§ 206, 211(f)(1), and 211(f)(4). EPA 

must explain what effect the proposed rule would have on the E15 partial waivers and misfueling 

mitigation rule and propose provisions to fill any potential regulatory gaps that are created by 

designating E15 a certification fuel. And, EPA must also address the major policy considerations 
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that flow from these key legal issues. EPA’s proceeding with a final test fuel rule for E15 at this 

time would clearly be unlawful under the Clean Air Act. We seriously question whether E15 can 

be lawfully made a test fuel under current circumstances for the reasons we have stated but 

certainly the Agency must do a far more thorough job of legal analysis in a re-proposal before it 

could seriously propose E15 as a test fuel. 

The EPA should set a new certification fuel as E10, not E15. It will be likely the predominant 

fuel in the marketplace.

Also on the certifying in a higher octane and higher ethanol content fuel, EPA should not go 

ahead of the requisite research and collaboration necessary to set new fuel specifications. And 

I’m out of time, so thank you for doing ppms.

Organization: Appalachian Mountain Club (AMC)

EPA proposes to update the federal emission test fuel to better reflect real world fuel. We 

generally support this concept and believe EPA should replace Indolene with the currently 

available ethanol blend E10. Higher ethanol blends have yet to be widely used in the marketplace 

and can impact greenhouse gas and fuel economy standards. EPA should use one consistent test 

fuel and consider the impacts across all of these regulations. 

Organization: BMW of North America, LLC

Harmonization of certification fuel is particularly crucial as with the new standards and 

increasing product complexity and regulation stringency manufacturers have to bear increased 

test burden. The proposed Tier 3 standard requires a different certification fuel than the 

certification fuel adopted by CARB’s LEV III program. In the interest of a 50-state certification 

and to avoid double testing, BMW proposes that EPA adopt an E10 fuel as required by CARB 

and allow in-use testing with the harmonized fuel. 

Organization: BP Products North America Inc.

Establish E10 as Emissions Test Fuel– BP supports a change in EPA’s federal emissions test fuel 

from Indolene to a fuel representative of the predominant, in-use gasoline. Recognizing the huge 

uncertainties underlying E15’s potential market penetration and the predominance of E10 in the 

market today, BP recommends that EPA adopt E10 as the test fuel for the foreseeable future. 

If/when E15 were to become the predominant, in-use gasoline, then and only then, should EPA 

adopt E15 as the test fuel. 

Organization: California Air Resources Board (CARB)

CARB staff disagrees with U.S. EPA’s decision to propose 15 percent by volume ethanol 

gasoline (E15) as the Tier 3 certification test fuel. 

E15 is currently used in a handful of fueling stations nationwide and its further penetration into 

the marketplace is uncertain. Given the practical considerations inherent in providing a refueling 
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infrastructure for E15, it may not proliferate very rapidly into the marketplace. On the other 

hand, E10 has been tested thoroughly as a viable fuel for all vehicles currently on the road and, 

as a result, will likely be widely used for the foreseeable future. However, should E15 constitute 

a significant fraction of the federal commercial fuel market at some future date, it would be 

appropriate at that time for U.S. EPA to reconsider the composition of Tier 3 certification fuel. 

Organization: Chevron Products Company

We are opposed to the designation of E15 as a certification fuel given that it is not representative 

of the fuel in wide use in the market and it is not compatible with most of the vehicles in the 

existing fleet. 

The proposal to shift the certification fuel to E15 ignores the many difficulties in marketing 

E10+ blends to the existing vehicle fleet. CRC has produced compelling data that demonstrate 

the incompatibility of E15 with millions of 2001+ vehicles. In addition, E15 remains illegal in 

California and will remain so for the foreseeable future. It is not clear when, if ever, E15 will be 

a practical product option. The potential for E10 and its higher RVP to continue to be the 

predominant gasoline used by Tier 3 vehicles creates a disconnection between certification 

requirements and real in-use emissions. Therefore, a more prudent path for EPA would be to 

adopt an El 0 certification fuel at this time, deferring an El5 fuel until market conditions justify 

the change. 

Organization: Chrysler Group LLC

Gasoline Emissions Test Fuel:

- Regulations that specify a fuel for testing purposes should match the fuel predominantly sold in 

the U.S., which we believe should be at least 70% prevalent in the marketplace. 

- The certification test fuel for gasoline-fueled vehicles should be an E10, 9.0 psi RVP test fuel, 

rather than an E15 certification test fuel.

- The exhaust and evaporative durability test fuel should also be representative of the

predominate fuel in the market, which is E10. 

- EPA should adopt a mechanism to accurately determine the point in the future at which E15 

becomes 70% prevalent in the marketplace, building in appropriate lead time. 

Definition of Commercially Available Fuel and Resultant Federal Test Fuel Requirements:

Chrysler believes that test fuels should match the predominant fuel in the marketplace. Matching 

test fuel to marketplace fuel will ensure vehicles deliver the performance and environmental 

benefits in the real world as they were certified. Chrysler thus believes that test fuel used in 

certification testing and also in durability mileage accumulation should be representative of the 

predominant fuel in the market. This includes the ethanol content of the gasoline. 

Accordingly, Chrysler supports updated Tier 3 test fuel requirements for gasoline-fueled vehicles 

to match test fuel to fuel that is predominate in the marketplace, but objects, however, to EPA’s 

proposal to require use of 15 percent ethanol by volume (E15) as the test fuel for certification 

testing beginning Model Year 2017. Requiring use of E15 would conflict with the objective to 

match test fuel to in-use fuel, because E15 is not the predominate fuel in the market. In addition, 
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Chrysler is concerned that EPA has not defined the term “commercially available,” as used in the 

fuel requirements for evaporative emissions durability testing. This concern is broadened where 

EPA, in a similar context, uses the phrases “commercial gasoline that will be generally available 

through retail outlets”, and “national average in-use fuels” to describe fuels for exhaust or 

evaporative durability service accumulation. Further, EPA, in seeking comment on the 

appropriateness of the alternative test fuel provisions at 40 C.F.R. § 1065.701(c), which also 

refers to fuels that would be “readily available nationwide” and implies this to mean 

“commercially available.” Chrysler finds these terms add considerable uncertainty when 

determining appropriate certification and durability test fuel requirements, and proposes that 

EPA adopt a single definition to represent the predominate fuel in the market that would apply to 

all test fuels. 

To the degree EPA seeks to interpret E15 as (1) “commercially available”, (2) a “national 

average in-use fuel”, or (3) “readily available nationwide’, Chrysler believes that E15, which is 

not currently available to the vast majority of American vehicle owners, is neither “commercially 

available”, “national average in-use fuel”, nor “readily available nationwide”. In order for EPA 

to require that any specific fuel blend, such as E15, be used in certification testing or durability 

testing, that fuel blend must be representative of the predominate fuel in the market. 

As EPA acknowledges in the proposed rule, E15 fuel is not representative of the currently 

prevailing gasoline in the marketplace. Instead, E10 is the predominate gasoline in the market. 

Moreover, there is no basis to believe that E15 will displace E10 as the predominate market 

gasoline in the foreseeable future. Although Chrysler recognizes EPA’s attempts to be “forward

looking” in selecting an appropriate long-term test fuel, the Agency’s unsupported assumptions 

of significant market penetration of E15 are too speculative at this point to support specifying the 

use of E15 as the federal test fuel for Model Year 2017 and beyond. 

Chrysler believes that EPA should define one term to describe the fuel that is predominate in the 

marketplace and therefore appropriate for fuels used in regulatory testing. In general, the 

meaning of the term “commercially available” in a legal or regulatory context is highly 

dependent on the context in and purpose for which it is used. For example, an item might be 

considered “commercially available” in certain contexts—where the objective is simply to 

ensure that the product can be obtained—if it can be purchased from an online provider, even if 

there is only one such provider and even if such provider is located in a geographically distant 

location. In the context of EPA’s fuel requirements for durability testing, however, it makes little 

sense to define “commercially available” in this fashion. Rather, in the durability testing context, 

the term “commercially available” is intended to ensure that testing is representative of real 

world in-use conditions — i.e., to ensure that manufacturers are conducting durability testing 

with a type of fuel that is representative of fuel that is actually being used in the marketplace. 

This ensures that durability in testing is likely to assure durability of cars in actual use. 

Obviously, gasoline cannot be ordered on the Internet or from a distant location. Rather, the 

ability to obtain the fuel has to involve ready access nearby to the routes of cars throughout the 

country. 

EPA appears to agree with this interpretation of the term “commercially available” in the 

preamble to the proposed rule:
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First, under the alternative test fuels provisions in 40 C.F.R. § 1065.701(c), a manufacturer must 

show that its proposed alternative test fuel is “commercially available.” EPA states in the 

preamble to the proposed rule that, pursuant to this provision, manufacturers can “petition the 

Administrator for approval of a higher octane, higher ethanol content test fuel if they could 

demonstrate that such a fuel . . . would be readily available nationwide. . . .” In other words, in 

the preamble, EPA interprets the term “commercially available” in the alternative test fuel 

context — with the same goal of using a fuel representative of real world conditions — to mean 

“readily available nationwide.” Chrysler supports this interpretation. 

Second, EPA states in the preamble to the proposed rule regarding the requirement in 40 C.F.R. 

§ 86.1823-08(d) that manufacturers use fuel with the highest ethanol content “commercially 

available” for purposes of evaporative emissions durability testing (7). With respect to 

this requirement, EPA states that “as E15 in-use fuel becomes progressively more available, we 

would expect that E15 service accumulation fuel would be used for whole vehicle evaporative 

durability programs.” Again, EPA indicates that the term “commercially available” excludes 

fuels, such as E15, that are currently available only at select service stations in limited states.

Even with this interpretation that “commercially available” means “readily available 

nationwide,” Chrysler believes that EPA must also specify the threshold for which a fuel is 

“readily available nationwide” in order to ensure that the industry has a clear understanding of 

what is required. In that light, the Onboard Refueling Vapor Recovery (ORVR) rules may 

provide a useful analogy for determining when market conditions have changed such that E15 

fuel may be deemed “commercially available” or “readily available nationwide.” Under the 

Clean Air Act, EPA has authority to waive certain requirements of the Stage II vapor recovery 

program when EPA finds that ORVR systems are in “widespread use” in the highway vehicle 

fleet. Because Stage II vapor recovery systems on gasoline pumps and ORVR systems on 

highway vehicles perform the same function (i.e., capture ambient vapors emitted during 

refueling), the reasoning goes, there would be little environmental benefit gained by requiring 

Stage II vapor recovery systems on gasoline pumps if ORVR systems on highway vehicles are 

already in “widespread use.” On May 9, 2012, EPA determined that ORVR was in “widespread 

use” and therefore waived the requirement that certain current and former ozone nonattainment 

areas implement Stage II vapor recovery systems on gasoline pumps. In reaching this 

determination, EPA relied in part on its marketplace finding that “75 percent of gasoline will be 

dispensed to ORVR-equipped vehicles by April 2012.” Therefore, a “widespread use” threshold 

of 70% to express “commercial availability” or “readily available nationwide” appears to be a 

reasonable threshold to determine commercial availability of gasoline for the purpose of defining 

test fuels, and is consistent with our proposal to have such test fuels be the predominate fuel sold 

in the marketplace. 

E15, which is not available except at twenty service stations across the United States, is not 

representative of the predominant market fuel in the U.S., nor is it commercially available for 

virtually all cars in the United States today. It is unclear when EPA might consider E15 to 

become “commercially available” such that it must be used for service accumulation during 

durability testing. EPA should clarify that the term “commercially available” should mean 

“readily available nationwide,” consistent with EPA’s apparent interpretation of the term in the

preamble to the proposed rule, and thus representative of the predominant fuel in the 
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marketplace. Today, only approximately twenty of the more than 120,000 retail outlets in the 

United States, or 0.017%, offer E15 fuel (13). Even E85, which is generally still not considered 

to be widely available in the marketplace, is available at approximately 2,350 service stations, or 

one hundred times as many stations as E15 (14). In the context of evaporative testing 

requirements to test on “highest ethanol content commercially available”, E85 does not meet the 

test of availability. Not only is E15 not the prevailing market fuel, it should not be considered 

“commercially available,” since only a tiny fraction of motorists can get it. It is unreasonable to 

consider a fuel “commercially available” if that fuel is only available at select service stations in 

a limited number of states. Accordingly, it is inappropriate for EPA to specify E15 as the test 

fuel for purposes of any of the motor vehicle testing requirements. 

Recommendation: Chrysler recommends that EPA define the fuel requirements for certification 

and evaporative emissions durability testing to mean the predominant fuel in the market, which 

we believe should be at least 70% of the fuel sold in the U.S. marketplace. We also recommend 

that EPA adopt a mechanism to determine, based on objective criteria and sufficient lead time, 

the point in the future at which the predominate fuel in the marketplace reaches that threshold. 

EPA proposes to adopt an E15 certification test fuel requirement for gasoline-fueled vehicles 

(15). However, E15 is not representative of the predominate fuel in the marketplace, which is 

E10. In fact, E15 is not even “commercially available” to the vast majority of American vehicle 

owners. As such, it is unreasonable and inappropriate to specify E15 as the certification test fuel. 

Chrysler supports EPA’s goal of specifying test fuel that best matches gasoline that the American 

public’s vehicles actually use (16). Chrysler also supports EPA’s goal of continuing to monitor 

the relationship between test fuel and in-use fuel so that testing is undertaken with fuel that 

represents real-world conditions. E10 is the fuel that the American public’s vehicles use, because 

it is the predominate fuel in the market; as such, EPA should designate E10, not E15, as the 

proper certification test fuel. Further, matching the ethanol content of certification test fuel to 

fuel used in the real world is important because the combustion of higher ethanol content 

gasoline (for example, of E15 versus E10, and both as compared to Indolene) tends to decrease 

volatile organic compound (“VOC”) and carbon monoxide (“CO”) emissions, but tends to 

increase oxides of nitrogen (“NOX”) emissions (17). Accordingly, adopting a higher ethanol 

content gasoline for certification testing is not necessarily “conservative,” because increasing the 

ethanol content of gasoline affects pollutants differently. 

Organization: Consumers Union; Consumers Union (comment campaign)

While Consumers Union supports EPA’s intention to match the certification fuel with the fuel in 

the market, we recommend an alternative plan in case the market for E15 does not overcome the 

significant barriers to its development and materialize by 2017. Even if E10 continues to be the 

dominant fuel in the market, testing vehicles for fuel economy purposes at E15 would be more 

accurate than the current E0 certification fuel. Adjustment factors can always be used to account 

for predicted differences (as they are now). However, uniform adjustment factors after the fact 

are never as precise as using the market fuel to begin with; automakers that maximize efficiency 

for E15 may distort fuel economy expectations of consumers using E10 at the pump. Therefore, 
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we would recommend that E10 be the default fuel, unless E15 comes to dominate the market, at 

which point a reasonable lead time could be provided to switch the certification fuel again.

Organization: Countrymark; Small Business Refiners (SBRs)

Adoption of a 15 percent ethanol by volume (E15) certification test fuel for gasoline-fueled 

vehicles.

EPA recommends matching today’s in-use gasoline federal emission testing fuel standard by 

replacing ‘Indolene’ (E0) fuel with 15% ethanol blend (E15). Justification for the change is to 

better match today’s in-use gasoline. 

According to EIA data, only eight fueling stations across three states were selling E15 by the end 

of 2012. As a comparison, more than 159,000 fueling stations were in service at the end of 2012. 

EIA and DOE both believe that E15 penetration into the market is not likely to occur in 

significant volume. 

In addition, the change to E15 is not supported by the oil industry, automotive industry, or 

consumer groups such as AAA because E15 brings several new problems to the market place. A 

few significant problems are listed below: 

- A higher blending ratio of ethanol is more corrosive, potentially resulting in engine damage or 

a shorter engine and fuel system operating life. 

- Containment failures cause greater environmental damage because ethanol promotes mixing of 

gasoline and water; which would not readily occur without ethanol being present. 

- Ethanol cannot be transported via pipeline like other transportation fuels. Ethanol must be 

shipped by rail or truck; resulting in additional investments for unloading and storage capacity. 

- Transporting ethanol by rail or truck increases greenhouse gas emissions, reducing the claimed 

benefit of using renewable fuels. 

- Blending E15 instead of E10 reduces the amount of butane that can be blended into gasoline. 

This directly reduces the refinery’s profitability and restricts flexibility in our operations because 

we need to find another disposition for butane instead of blending with gasoline. 

Organization: Countrymark

CountryMark is not interested in producing E15 and recommend that the fuel standard be 

changed to a 10% (E10) blend of ethanol to represent today’s in-use gasoline based on fuel 

demand across the country. 

CountryMark started blending ethanol at ten percent long before being obligated under the RFS 

because it made economic sense. We have not sold CBOB (Conventional Blend stock for 

Oxygenate Blending) or RBOB (Reformulated Blend stock for Oxygenate Blending) to support 

E15 since it was approved as a fuel option. CountryMark is not planning to incorporate E15 as a 

major volume product into our portfolio of offerings to our customers. We do not see sufficient 

demand to justify changing operations at our refinery to meet E15 specifications. 

Organization: Small Business Refiners (SBRs)
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The SBRs are opposed to a requirement to produce E1S and recommend that the fuel standard be 

changed to a 10% (E10) blend of ethanol to represent today’s in-use gasoline based on fuel 

demand across the country. 

Organization: E.I. du Pont de Nemours and Company

Of particular interest to DuPont is EPA’s proposal to set E-15 as certification fuel. Renewable 

fuels have a bright future in the U.S. and the Tier 3 proposed rule includes a number of 

provisions that can support making renewable fuels more widely available and economically 

competitive. Expanding renewable fuels will ultimately drive reductions in air pollutants that are 

the target of the Tier 3 rule. 

Setting E-15 as certification fuel is also the baseline for evaluating the health effects of the fuel 

and associated fuel additives, a mandatory part of the Part 79 registration process. DuPont 

suggests that EPA recognize this in the final rule and address how this fact affects existing and 

future registrations. 

First, DuPont supports EPA’s proposal to set E-15 as emissions test fuel for light-duty cars and 

trucks as well as heavy-duty gasoline vehicles. EPA must create the requisite incentives for auto 

manufacturers to pursue advanced engine technologies. Setting E-15 as test fuel is a step in the 

right direction. 

EPA is requesting comment on alternative approaches to implementing E-15 as test fuel. Two of 

the options include requiring E-15 to be available on the market before transitioning to E-15 as 

test fuel. Instead, DuPont suggests that EPA set a specified future date for transitioning to E-15 

test fuel. This approach would ensure E-15 as test fuel providing certainty for fuel producers and 

auto manufacturers, and provide the requisite incentives to automakers to advance engine 

technologies. 

Organization: ExxonMobil

If the Agency decides to proceed with this rulemaking, we recommend that EPA: specifies E10 

as the new vehicle certification fuel. 

Organization: General Motors LLC (GM)

The basic foundation of today’s Federal Certification Test Fuels (hereafter “test fuels”) has been 

in place and relatively unchanged since 1975. GM supports updating and expanding the test fuel 

to be aligned with current predominate market fuel. We advocate that EPA’s final Tier 3 rule 

specify an E10 9 psi RVP test fuel gasoline rather than the proposed E15 test fuel that does not 

represent the market. There are only about 20 U.S. retail outlets selling E15 to date and most of 

these do not offer E15 during the summer. Because there are many uncertainties about the further 

expansion of E15, EPA’s “forward looking” approach assumes significant national market 

penetration of E15 that is too speculative for something as important as the Federal test fuel for 

2017 and beyond. 
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As mentioned above, transitioning to an E15 test fuel is too speculative for something as 

important as the Federal test fuel for 2017 and beyond. If there needs to be a provision to 

recognize E15 in the future, then GM suggests a two-step approach.

Organization: Private Citizen

However, I do not support the new proposal for E15 gasoline since this fuel has not yet been 

adequately tested on non-flex fuel gasoline engines, or proven safe for motorcycles or other 

small engines. Besides, we already have 10% ethanol (E10) which is enough to help reduce 

tailpipe emissions without creating excessive problems due to ethanol’s incompatibility with fuel 

system materials and designs in older vehicles. Ethanol-blend fuels reduce fuel economy (miles 

per gallon) due to lower energy content, and they often cause damage to fuel systems... doing 

this in the name of cleaner air just does not make sense to me. There’s got to be a better way to 

deal with the ethanol issue, and I urge you to please oppose the introduction of E15 without 

adequate testing. 

Organization: Growth Energy

Growth Energy Strongly Supports an E15 Certification Fuel. Growth Energy saw the need for 

additional market space for the higher biofuel volumes called for under the RFS and 

subsequently filed the Green Jobs waiver for E15 with the Agency in 2009. In January 2011, the 

Agency approved the waiver for 2001 and newer light duty vehicles. While the critics have done 

everything in their power to prevent higher ethanol blends in the marketplace, EPA has 

appropriately proposed that all 2017 and newer vehicles should be certified on E15 – clearly the 

fuel of the near future. Nearly the entire American vehicle fleet fuels on E10 today rather than 

E0. Now that EPA has approved E15 and the U.S. Supreme Court has denied cert on the critics’

lawsuits to prevent the implementation of the E15 waiver, it only makes sense that the 

automakers and the American public move forward with what EPA views as a major 

transportation gasoline blend in the near term. With the approach of the RFS blend wall, it only 

makes sense that we will begin to see more E15 in the marketplace. Additionally, more than 70 

percent of the vehicles on the road have been approved by EPA for use with E15 (model years 

2001 and newer), and two major automobile manufacturers, Ford and General Motors, are 

already warrantying their newer vehicles for E15 – GM for model years 2012 and 2013 and Ford 

for model year 2013 (Oil Price Information Service, October 2, 2012 “Ford and GM Okay E15 

Blends for Newer Vehicles”). 

Organization: INEOS Bio

EPA requests comment on various ways to transition the emissions test fuel, including: starting 

with a transition to E10 with a transition to E15 as that fuel becomes more widely available on 

the market; transitioning to E15 after a few years to allow time for this greater market 

availability or by setting a date certain by which the transition should be made to help drive E15 

market availability; or, allowing “vehicle manufacturers to request approval for an alternative 

certification fuel, such as a high-octane 30 percent ethanol by volume (E30) for vehicles they 

might design or optimize to use such a fuel” so that it may “help manufacturers that wish to raise 
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compression ratios to improve vehicle efficiency, as a step towards complying with the 2017 and 

later light-duty greenhouse gas and CAFE standards.” 

INEOS Bio commends EPA’s efforts to transition the certification test fuel for emissions from 

light duty cars and trucks and heavy duty gasoline vehicles (“the emissions test fuel”) to better 

reflect the current and future in-use fuel as it begins to contain greater volumes of biofuels 

resulting from the continued development and commercialization of biofuels and increased RFS 

volumes in the market. 

INEOS Bio believes that EPA should work to set the emissions test fuel to promote the highest 

achievable level of ethanol and octane in the U.S. fuel supply. Encouraging the highest 

achievable level of biofuels would help meet EPA’s overall goal in this rulemaking to address 

the impacts of motor vehicles and fuels on air quality and public health. (11) For instance, 

cellulosic ethanol from waste in comparison to gasoline contains no sulfur and has over 100% 

reduced GHGs. In addition, ethanol combusts without producing air toxics, which are the main 

source of particulate matter. Blending ethanol in gasoline also reduces the need for unhealthy 

detergent additives which are mandated to reduce the formation of engine deposits from gasoline 

that increase exhaust emissions and result in the loss of fuel economy and performance. These 

benefits of ethanol only rise with higher blends, so INEOS Bio encourages EPA to issue a final 

rule that would encourage and drive the highest achievable blend which we feel in this given 

market would be E15. 

Organization: International Council on Clean Transportation (ICCT)

While the ICCT supports using a more representative fuel for certification testing, E15 is not 

representative of in-use fuel. E15 can cause damage if it is used in small engines or in legacy 

vehicles. E15 is also specific to ethanol, which encourages the use of food feedstocks instead of 

more environmentally friendly feedstocks. Finally, E15 provides significant evaporate cooling, 

which manufacturers could exploit to generate higher fuel economy on the tests than the vehicles 

actually experience in use. The ICCT recommends that the test fuel use E10. 

The ICCT is concerned about the proposed revision to use E15 for the certification test fuel. 

While the ICCT supports using a more representative fuel for certification testing, E15 is not 

representative of in-use fuel. E10 is representative of current in-use fuels and should be used for 

emission and fuel economy testing. 

In addition to violating the principle of using representative fuels, the ICCT has a number of

serious concerns with E15: E15 can cause damage if it is used in small engines or in legacy 

vehicles; it is specific to ethanol (as opposed to drop-in biofuel pathways), which encourages the 

use of food feedstocks such as maize instead of more environmentally friendly feedstocks; and it 

provides significant evaporative cooling, which manufacturers could exploit to generate higher 

fuel economy on the tests than the vehicles would actually experience in use. 

The problems and potential damage if E15 is used in small engines and legacy vehicles has been 

well documented by Honda and other vehicle manufacturers and will not be repeated here. 

However, our concerns in this area are exacerbated by the lack of systems to provide proper fuel 
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and prevent misfueling in-use. For example, EPA has not proposed a system to separate the use 

of E15 for newer vehicles and E10 for older vehicles. A system where E15 is used for regular 

fuel and E10 for premium fuel would encourage misfueling of small engines and legacy vehicles,

as customers choose E15 just because it is cheaper. If E10 is used for regular fuel and E15 is 

used for premium fuel, this would discourage the use of E15 in vehicles that could safety use it 

and would make it impossible for older vehicles requiring premium to be refueled properly. 

Thus, for the refueling system to work properly, it appears that service stations must provide 

separate pumps for both E10 and E15 for both regular and premium. This is not likely to happen 

unless EPA requires it. Until EPA addresses the refueling situation with regulations, refueling 

will almost certainly be marked by confusion and misfueling. 

The ICCT is also concerned that E15 will encourage biofuels made from food crops, instead of 

advanced biofuels. It is not currently cost effective to make ethanol out of cellulose, thus simply 

increasing the ethanol blend wall is effectively a mandate for more food-based biofuels that can 

easily be turned into ethanol. Several pathways for producing advanced biofuel from feedstocks 

such as cellulose will likely be able to deliver drop-in fuels. As drop-in fuels have a higher value 

in the market than ethanol, it is also possible that cellulose can be more profitably turned into 

drop-in fuels. E15 would work against this by incentivizing ethanol, not drop-in fuels. Insofar as 

wider use of E15 supports increased use of maize and sugarcane ethanol rather than driving 

investment into advanced drop-in fuel pathways, the net result will be that E15 would tend to 

increase food prices (and hence worldwide food insecurity), decrease biodiversity due to land use 

change, create yet another roadblock for advanced, lower carbon, biofuels and deliver less 

carbon reductions than would be available from commercializing biofuels from cellulosic wastes 

and energy crops.

The ICCT’s third concern is specific to fuel economy testing. 15% ethanol content provides 

significant evaporative cooling in the cylinder. This would allow manufacturers to advance 

ignition timing or make other modifications to improve fuel economy on the test cycles—and 

which would not be likely to be achieved in-use. 

The advantages of even E10 were demonstrated in a test program to maximize engine power on a 

variety of fuels. Grassroots Motorsports (December 2012) tested a Mazda Miata on the following 

fuels, using a standalone computer to tune the vehicle for each fuel on a Dynapack dynamometer 

to make the most power: The charge cooling effect of E10 boosted performance on 93-octane 

fuel by about 1.5% and virtually matched the performance of 100 and 105-octane race gasoline. 

GRM couldn’t redesign the engine and they were only able to revise spark timing, camshaft 

timing, and air/fuel ratio at WOT. The higher charge cooling with E15 would allow 

manufacturers to do even more optimizing—and they could also optimize the design of the 

engine over all operation. 

It is important that the fuel used for certification and fuel economy testing be representative of 

in-use fuel. However, that fuel is currently E10, which is what should be used for EPA’s testing. 

E15 is not currently representative of in-use fuel and its use for EPA testing has several major 

problems, which should be avoided. 

Organization: Marathon Petroleum Company LP (MPC)
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EPA must also change the proposed certification fuel to a 10% ethanol blend with the 1 psi 

waiver that is more representative of current and future transportation gasoline.

EPA proposes to change the gasoline test fuel for light-duty and heavy-duty vehicles from E0 

fuel to E15 fuel. 78 Fed. Reg. at 29825. EPA does not state its legal basis for designating test 

fuels, and instead asserts in a conclusory way that “we believe we have discretion under the 

statute to transition from E0 to E15 test fuel....” Id. at 29910. 

EPA presents essentially no factual basis for this proposed change to E15. According to EPA, 

“[i]n-use gasoline has changed considerably since EPA’s fuel specifications for emissions testing 

of light- and heavy-duty gasoline vehicles were last set and first revised.” Id. at 29908. EPA 

predicts that the second iteration of the federal renewable fuels standard program (“RFS2”) will 

lead to further changes in in-use fuel, including “expansion of the number of retailers that offer 

E15.” Id. In response to changes in in-use fuel that EPA alleges have already occurred, as well as 

“forward-looking” predictions about the ethanol and sulfur content of future in-use fuels, EPA 

proposes to update the gasoline test fuel provisions of 40 C.F.R. § 1065.710. Id. EPA proposes to 

make this change despite its admission that “E15 is only commercially available at a limited 

number of fuel retailers” at present. Id. at 29909. EPA’s prediction about increased E15 fuel 

availability in the future is premised on “instability in crude oil pricing and growing RFS2 

renewable fuel requirements.” Id. 

EPA seeks comment on its proposed approach of changing the test fuel from E0 to E15, 

including the “forward-looking nature” of this proposal. Id. at 29910. Additionally, EPA seeks 

comment on potential alternative approaches, including designation of E10 as the test fuel and 

later “transition to E15 as the market further transitions to E15 in use.” Id. 

EPA should specify E10 as the certification fuel. The CAA requires EPA “to insure that vehicles 

are tested under circumstances which reflect the actual current driving conditions under which 

motor vehicles are used, including conditions relating to fuel, temperature, acceleration, and 

altitude.” CAA § 206(h). Accordingly, test fuels must “reflect current driving conditions.” Id. 

(emphasis added). 

In keeping with this clear statutory requirement, we agree with EPA that the certification fuel 

should be switched to an ethanol containing blend because ethanol blends are the most prevalent 

type of gasoline currently in the market place. However, we disagree with the proposed selection 

of E15. As was stated in the RIA, most gasoline in the United States contains 10% ethanol by 

volume. The certification fuel should represent the most common grade of fuel sold, which is 

E10. Likewise, the octane rating should coincide with the dominant grade which is 87 AKI 

regular unleaded. The only exception should be for engines that require premium unleaded fuel 

as stipulated in the vehicle owners’ manual. 

We disagree with EPA’s proposal to select a fuel that is “forward looking with respect to the 

maximum gasoline ethanol concentration Tier 3 vehicles could expect to encounter.” Id. This 

creates two fundamental legal problems. 
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First, establishing a “forward looking” test fuel violates the statute because a “forward looking” 

fuel such as E15 does not accurately or reasonably reflect the “current” fuels used by affected 

vehicles. The plain language of the statute does not permit EPA to substitute the phrase “forward 

looking” for “current”. EPA’s own analysis shows that E10 is the most prevalent ethanol blend 

in the market today. Thus, E10 is the only ethanol blend that may be specified as a test fuel at 

this time. 

Second, even if the statute could be construed (arguendo) as authorizing EPA to set a “forward 

looking” test fuel, EPA has not put forward adequate factual justification to do so in this case. 

EPA’s proposed “forward looking” E15 test fuel is based on the assertion that E15 “could 

become a major gasoline blend over the next 10-15 years.” Id. at 29909. However, there are no 

data or analyses in the proposal or underlying record that support this prediction. Absent such 

factual support, adopting E15 as a test fuel would be arbitrary and capricious. 

Notably, even if the Agency attempted to assemble factual justification for a “forward looking” 

E15 test fuel, it could not do so. Given the lack of announced E15 compatible vehicles, 

automobile manufacturer warranty statements, lack of refueling infrastructure and the 15 to 18 

year timeframe to turn over the vehicle fleet, E10 will continue to reflect “current driving 

conditions” over the timeframe under consideration by EPA. 

In light of these problems, the only legally-viable course would be to select E10 as the 

certification fuel and transition to E15 if and when E15 become the most prevalent fuel in the 

market. We support a market review at some point in the future after 2017 to gauge E15 usage 

and growth projections. This review could coincide with the technology review for the CAFE 

standards. The certification fuel should not switch to E15 until it becomes the dominant fuel in 

the marketplace. 

Lastly, if EPA ultimately decides to switch to E15, that switch must be accomplished through 

notice and comment rulemaking. EPA suggests in the proposal that such a switch might be

accomplished automatically in the future by establishing “a ‘‘trigger point’’ (e.g., 30 percent of 

gasoline is E15) in the Tier 3 final rule to prompt an automatic move to E15 after a certain period 

of time, e.g., two or three years.” Id. at 29910 EPA alternatively suggests that it “could simply 

set a future date (e.g., 2020) with sufficient time for transitioning to E15 test fuel.” Id. Neither of 

these approaches is legally viable. 

Switching to E15 based on a 30% trigger would require a future factual determination that the 

30% trigger has been exceeded. Such a determination constitutes “factual data” that must be set 

out in a proposed rule before EPA may take a final action based on those data. CAA § 307(d)(3). 

Switching to E15 at a fixed point in the future based on a current prediction of when E15 will 

become the prevalent fuel is problematic because, as explained above, EPA has not set out 

sufficient data or analyses to justify a prediction as to when E15 might become the most 

prevalent gasoline. Thus, the only viable way to establish E15 as a test fuel is to do so through 

notice and comment rulemaking at the point when and if E15 becomes the dominant ethanol 

blend in the market. 
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EPA proposes to increase ethanol content from zero to 15 volume percent. EPA believes that this 

level is forward-looking with respect to the maximum gasoline ethanol content Tier 3 vehicles 

could expect to encounter. Concerns with vehicle fuel system compatibility still need to be 

addressed in advance of its introduction into commerce. This level of ethanol is also not aligned 

with CARB LEV III test fuel which is set at 10 volume percent. To ensure the most effective 

evaporative emissions control system for in-use operation we would suggest that EPA considers 

setting the ethanol content at 10 volume percent and then adjusting the RVP requirement of the 

certification fuel to account for the allowed 1 psi waiver. Once the manufacturers all warrant 

their vehicles for E15, and E15 represents a dominant portion of the overall market (including 

California) then it would be appropriate for EPA to consider shifting to an E15 certification fuel 

while ensuring no loss of effectiveness of the emission control systems. 

Legal justification for new test fuel – EPA has failed to explain the legal basis for its test fuel 

proposal. EPA asserts that the primary legal authorities for the proposed rule are CAA §§ 202, 

206, and 211. 78 Fed. Reg. at 29828-29. EPA rulemaking pursuant to these provisions is subject 

to the requirements of CAA § 307(d). See § 307(d)(1)(E), and (K). Pursuant to § 307(d)(3), EPA 

is required to include in the proposal the “statement of its basis and purpose” for the action, 

which must include “the major legal interpretations ... underlying the proposed rule.” 

Yet, EPA does not include any discussion in the proposal of the legal basis for the proposed test 

fuel provisions. For example, there is no explanation of what section or sections of the statute 

authorize it to designate a new test fuel. Similarly, there is no discussion of the scope and extent 

of the Agency’s authority to establish test fuels and specify particular parameters that such fuels 

must meet. The Agency simply asserts that “we believe we have discretion under the statute to 

transition from E0 to E15 test fuel.” 78 Fed. Reg. at 29910. 

Because EPA has not provided any explanation of the statutory authority on which it relies for 

the proposed test fuel provisions, MPC has no opportunity to comment on that key issue and any 

rule promulgated would be contrary to the Clean Air Act and unlawful. To try to resolve this 

problem, EPA must re-propose the rule to provide an opportunity to comment on the Agency’s 

legal basis for designating a new gasoline test fuel. 

EPA has failed to consider fully the CAA § 211(f) implications of its test fuel proposal. Section 

211(f) limits the fuels and fuel additives that a manufacturer may lawfully “introduce into 

commerce, or [] increase the concentration in use of.” Pursuant to § 211(f)(1) and (2), only those 

fuels and fuel additives that are “substantially similar to any fuel or fuel additive utilized in the 

certification of any model year 1975, or subsequent model year, vehicle or engine under section 

[206 of the CAA]” may enter commerce for general use in light duty vehicles, or for use by any 

person in any motor vehicles, manufactured model year 1974 or later. (Emphasis added.) EPA 

may grant a § 211(f)(4) waiver from these commercial limitations if the requested waiver “will 

not cause or contribute to a failure of any emission control device or system (over the useful life 

of the motor vehicle, motor vehicle engine, nonroad engine or nonroad vehicle in which such 

device or system is used) to achieve compliance by the vehicle or engine with the emission 

standards with respect to which it has been certified under pursuant to sections [206 and 

213(a)].” 
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As EPA explains in the preamble to the proposed rule, pursuant to § 211(f)(4), EPA granted a 

partial waiver for use of E15 by light-duty vehicles model year 2007 and later, and then extended 

the waiver to include model year 2001-2006 light-duty vehicles. 78 Fed. Reg. at 29909 n. 320 

(citing 75 Fed. Reg. 68094 (Nov. 4, 2010) and 76 Fed. Reg. 4662 (Jan. 26, 2011)); see also id. at 

29911. EPA also concluded at the time that E10 was not a certification fuel for purposes of 

determining whether mid-level blends could be put into commerce under the authority of § 

211(f)(1) (under a “substantially similar” determination) rather than pursuant to a waiver issued 

under § 211(f)(4). 75 Fed. Reg. at 68143. In issuing those partial waivers, EPA placed conditions 

designed to, among other things, minimize potential misfueling. EPA complemented those 

conditions through a later rule, known as the “E15 Misfueling Mitigation Measures Rule,” which 

included misfueling prohibition, fuel pump labeling, PTDs, and ongoing implementation survey 

requirements as a “direct and efficient way to further reduce the potential for misfueling and the 

emission increases that would result from misfueling.” 76 Fed. Reg. 44406, 44411 (July 25, 

2011) (emphasis added); see also 78 Fed. Reg. at 29911. EPA stated that these additional 

requirements were directed to “E15 that is introduced into commerce in accordance with the 

partial waivers” and thereby operated “collectively and in tandem with the partial waiver 

conditions [to] maximize the likelihood that E15 is used only in motor vehicles covered by the 

partial waivers and minimize the potential for emissions increases that might otherwise occur.” 

Id. (emphasis added).

EPA proposes to establish E15 as a certification fuel for purposes of implementing the Tier 3 

standards. This raises two legal issues that EPA has failed to address in the proposal: (1) will 

establishing E15 as a certification fuel authorize E15 to be put into commerce pursuant to § 

211(f)(1); and (2) if so, what effect does this have on the previously-issued E15 partial waivers 

and corresponding misfueling mitigation rule? EPA’s failure to address these key questions 

violates its rulemaking obligations under § 307(d)(3) and renders the proposed rule arbitrary and 

capricious due to the Agency’s failure to identify and address key policy and legal implications 

of designating E15 as a certification rule. 

On the question of whether establishing E15 as a certification fuel authorizes E15 to be put into 

commerce pursuant to § 211(f)(1), language in the preamble seems to suggest that in EPA’s 

view, once EPA designates E15 as a test fuel under § 206, E15 could be introduced into 

commerce only for the vehicle type(s) for which E15 were specifically authorized for use as a 

test fuel. For example, manufacturers could introduce into commerce E15 for use into heavyduty vehicles without a § 211(f)(4) waiver “[i]f . . . new heavy-duty gasoline vehicles or engines 

begin testing on E15 for certification.” 78 Fed. Reg. at 29911. Under this implied legal analysis, 

commenters are left to guess about many key aspects of this important issue. For example, does 

EPA believe this is how the statute must be interpreted? If not, what other interpretations did 

EPA consider and why were alternative interpretations rejected? 

For example, some might suggest that, under Section § 211(f)(1), if E15 were designated a new § 

206 test fuel, E15 could be introduced into commerce for use in any vehicle without a § 211(f)(4) 

waiver. This view might be supported by the assertion that Section 211(f)(1) does not appear to 

place any limitation on the vehicle types for which a fuel can be introduced into commerce once 

that fuel is designated as a test fuel under § 206. Therefore, assuming arguendo that E15 were 

designated as a test fuel only for light-duty vehicles, it could still be introduced into commerce as 
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a fuel for use in any vehicle under § 211(f)(1). We would view such an approach as not 

authorized by the Clean Air Act and therefore unlawful, yet, EPA does not explain how the 

sweeping language of § 211(f)(1) can or should be construed as being as highly constrained as it 

appears to suggest. Thus, EPA’s treatment of this key issue falls far short of the Agency’s § 

307(d)(3) obligation to clearly set out “the major legal interpretations and policy considerations 

underlying the proposed rule.” 

As importantly, EPA also essentially failed to explore the obvious and important implications of 

introducing E15 into commerce under § 211(f)(1) with regard to the previously-issued E15 

partial waivers and misfueling mitigation rule. For example, if E15 may be put into commerce 

under § 211(f)(1), do the previously-issued E15 partial waivers continue to have relevance, 

meaning, or legal applicability? Would the waivers essentially be rendered moot (if E15 may be 

introduced into commerce under § 211(f)(1) by virtue of E15 becoming a certification fuel), and 

does EPA have authority to limit the types of engines/vehicles that may use E15, as it did under 

§ 211(f)(4) by issuing the so-called “partial waivers?” Similarly, does the misfueling mitigation 

rule have any force or effect, given that it was issued for purposes of facilitating implementation 

of the E15 partial waivers? If it does remain in effect, is the misfueling mitigation rule adequate 

given that it was designed to be implemented in conjunction with the misfueling mitigation 

measures required to be implemented as a condition of using the E15 partial waivers? These are 

just a few examples of the many important questions that arise by virtue of designating E15 as a 

certification fuel. 

We certainly reserve our ability to challenge each and every one of these issues and the most that 

EPA says on these important issues is in its discussion of the potential use of E15 in heavy-duty 

vehicles, where the Agency notes that the potential for misfueling in heavy-duty vehicles would 

be addressed in a future action. 78 Fed. Reg. at 29911. Thus, EPA’s treatment of this key issue 

falls far short of the Agency’s § 307(d)(3) obligation to clearly set out “the major legal 

interpretations and policy considerations underlying the proposed rule.” As a result, EPA must 

re-propose the rule and set forth a clear interpretation of §§ 206, 211(f)(1), and 211(f)(4). EPA 

must explain what effect the proposed rule would have on the E15 partial waivers and misfueling 

mitigation rule and propose provisions to fill any potential regulatory gaps that are created by 

designating E15 a certification fuel. And, EPA must also address the major policy considerations 

that flow from these key legal issues. EPA’s proceeding with a final test fuel rule for E15 at this 

time would clearly be unlawful under the Clean Air Act. We seriously question whether E15 can 

be lawfully made a test fuel under current circumstances for the reasons we have stated but 

certainly the Agency must do a far more thorough job of legal analysis in a re-proposal before it 

could seriously propose E15 as a test fuel. 

Organization: Maryland Department of the Environment

When reviewing the use of ethanol in the certification fuel, we would recommend that EPA, in 

the final rule, specify E10 as the test fuel. This recommendation is based on data at this time that 

shows that E15 is only a small segment of the U.S. fuels market, it currently is not use in 

Maryland, and it is questionable at this point if this fuel will see wide spread automotive use. In 

addition, in the past MDE has voiced its concern over the use of E15 based on its increased 

volatility which leads to increased ozone emissions particularly in the summer months. 
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Organization: American Energy Alliance (comment campaign) 

One overlooked part of this proposed rule is that it also changes the “vehicle certification fuel” to 

E15 (gasoline that is 15 percent ethanol). This is a stealthy way for EPA to get much more widespread adoption of E15 fuel at gas stations, a mandate that threatens engines and forces 

Americans to use a less efficient fuel. 

Organization: National Association of Clean Air Agencies (NACAA)

Use of Ethanol in Certification Fuel — NACAA supports the concept of ensuring that fuels used 

for certification purposes should more closely reflect real-world fuels. Given the prevalence of 

E10 (gasoline containing 10 percent ethanol by volume) in the marketplace, we encourage EPA 

to replace the currently used indolene with E10 as an emissions certification fuel. We are 

concerned that EPA has proposed to require that E15 be used as certification fuel. At this time, 

E15 is only a small segment of the U.S. fuels market and the prospect of it becoming a widely 

used automotive fuel in the future is questionable. Further, use of E15 in the existing vehicle 

fleet will have adverse impacts on vehicle emissions (e.g., aldehydes or NOx). Therefore, we 

recommend that in the final Tier 3 rule EPA specify E10 as a test fuel and continue to monitor 

the use of E15 in the marketplace. Should use of E15 become significant, the agency can then 

consider the pros and cons of revising test fuel specifications to include E15. 

Organization: National Association of Convenience Stores (NACS) and Society of 

Independent Gasoline Marketers of America (SIGMA)

The Proposal would make E15 the default test fuel for most non-flex-fuel vehicles (“FFVs”). At 

the present time, E10 is the predominant fuel in the market. It appears unlikely that E15 will gain 

significant market share in the immediate future. NACS and SIGMA do not oppose making E15 

the test fuel provided that vehicles certified on E15 do not experience significant deterioration in 

their performance when they run on E10. If such performance problems do occur, the Agency 

must consider delaying designating E15 as the default test fuel, and, instead, make E10 the test 

fuel until E15 is more widely available and utilized. 

By developing specifications for ethanol-based fuels, and requiring other potential fuels of the 

future to petition the Agency for approval as a test fuel, the Proposal could entrench ethanol’s 

current role in the fuel supply, and impose artificial impediments to new fuels coming to market. 

Certification Fuels:

The Proposal would update the specifications of the certification test fuel with which vehicles 

demonstrate compliance with emissions standards. For non-FFVs, the Proposal moves away 

from “Indolene” (“E0”) to an E15 test fuel. In addition, the Proposal would for the first time 

impose detailed specifications for the E85 emissions test fuel used for FFV certification. Finally, 

the Proposal would allow vehicle manufacturers to request approval for an alternative 

certification fuel for vehicles they might design or optimize for use on such a fuel. 

Non-FFVs:
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The Proposal designates E15 as the test fuel for most non-FFVs to demonstrate compliance with 

emissions standards. NACS and SIGMA members recognize and appreciate that the Agency is 

trying to be “forward-looking” in designating E15 as the test fuel. While E10 blends are 

relatively standard across the country, much higher percentages of ethanol—including E15—will 

need to be consumed to satisfy the RFS’s increasing consumption targets. If E15 is going to be 

the predominant fuel in the future, the market needs adequate notice so it can, among other 

things, adjust its infrastructure accordingly. 

Of course, the Proposal designates E15 as the default test fuel before that fuel has made any 

substantial inroads into the marketplace. At the present time, E10 is the predominant fuel, and 

there are few indications that this will change in the immediate future. The Proposal would 

nonetheless require vehicle manufactures to calibrate their vehicles to meet the proposed Tier 3 

standards on fuel containing 15 percent ethanol by volume. NACS and SIGMA do not oppose 

this provided that vehicles certified on E15 do not experience significant deterioration in their 

performance when they run on E10. If such performance problems do occur, the Agency must 

consider delaying designating E15 as the default test fuel, and, instead, make E10 the test fuel 

until E15 is more widely available and utilized. 

The retail market is not ready to accommodate sufficient volumes of higher fuel blends to satisfy 

the RFS requirements at the present time. From retailers’ perspective, a primary concern is 

infrastructure compatibility. By law, all equipment used to store motor fuel—including 

underground storage tanks (“USTs”) and dispensers (gas pumps) must be certified by a 

nationally recognized testing laboratory.4If a retailer fails to use appropriately certified 

equipment, that retailer may also be violating tank insurance policies, state tank fund program 

requirements, bank loan covenants, and other local regulations. In addition, the retailer could be 

found negligent per se based solely on the fact that his fuel dispensing equipment is not certified. 

Currently, there is essentially only one organization that certifies such equipment – Underwriters 

Laboratories (“UL”). 

Prior to 2010, UL had not listed a single dispenser as compatible with any fuel containing more 

than 10% ethanol. This means that any dispenser in the market prior to 2010 is not legally 

permitted to sell E15, E85, or anything else above 10% ethanol. As a practical matter, this means 

that a significant number of retailers wishing to sell blends >E10 must replace their dispensers, at 

an average cost of $20,000 per dispenser. For some retailers who operate specific models of 

dispensers, there are UL-approved retrofit kits now available for approximately $4,000, but the 

number of units that can utilize these kits is uncertain. Further, a substantial majority of UST 

systems may have to be replaced as well. Once a retailer begins to replace underground 

equipment, the cost can escalate rapidly and can easily exceed $100,000 per location. (Many of 

these units are manufactured to be compatible with high concentrations of ethanol, but are not 

listed as such by UL.) 

For a significant number of fuel retailers across the United States, these costs preclude them from 

upgrading their infrastructure. Unless Congress or the Agency develops a mechanism by which 

current equipment is permitted to store and dispense higher fuel blends lawfully, retailers will 

remain reluctant to market E15. That the RFS mandates will continue to escalate annually does 
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not change this fact. Designating E15 as the default test fuel for most motor vehicles on the road 

will also not change this fact. 

Further, and perhaps more importantly, until consumers indicate their desire to purchase E15, 

very few retailers will consider offering the new fuel even if their equipment is legally approved 

to do so. Since the approval of E15, there has been no discernible effort to generate consumer 

demand and encourage the availability of this product in the market. Quite the contrary, most 

information readily available to consumers discourages the use of E15. 

Therefore, if designating E15 as the default test fuel for non-FFVs could impair vehicles’ ability 

to run on E10, NACS and SIGMA urge the Agency to make E10 the default test fuel to better 

reflect market realities. This does not preclude the Agency from transitioning to E15 if legal and 

logistical barriers are removed. This could include a market review in the next several years and, 

if warranted, further regulatory action to implement the change from E10 to E15. 

Organization: National Automobile Dealers Association (NADA)

EPA should not approve E15 as a test fuel given its lack of presence in the marketplace and 

should not mandate a test fuel above 9 psi RVP. 

To enable Tier 3 tailpipe standard compliance, EPA should establish a 10 ppm gasoline sulfur 

average with a 25 ppm cap. To enable Tier 3 evaporative emissions compliance, a Reid Vapor 

Pressure (RVP) cap should be set at 9 psi for a maximum E10 gasohol test fuel. 

Organization: National Corn Growers Association (NCGA)

We are supportive of the EPA’s approach toward establishing E15 as the new certification fuel 

for 2017 and later non-flexible fueled light duty vehicles and the lower sulfur specifications for 

in-use gasoline. 

EPA has proposed changing the certification test fuel from one containing no ethanol to E15 

with a volatility of 9 psi and an AKI of 87. 

Separate from the Tier 3 rule, EPA approved the use of E15 in 2001 and later on-road motor 

vehicles (5). It would not make sense to certify new motor vehicles on E0, or even E10, when 

EPA has approved the use of E15 in these vehicles. Nearly all vehicles in the United States are 

currently fueled with E10, and the RFS volume requirements will increase the renewable fuel 

content in the United States beyond today’s levels. Therefore, it is important that the 2017 and 

later model year vehicle fleet be certified on the expected future ethanol content rather than the 

historic ethanol content. 

We believe E15 certification test fuel should be introduced for the 2017 vehicle model year as 

EPA has proposed. In view of the long history of ethanol use as E6, E10 and E85, the 

understanding of materials compatibility and engine and emission impacts of ethanol blends in 

the literature for 30 years, it seems that a phase-in schedule might not be required to design and 

calibrate for E15. EPA discussed potential delays in the introduction of E15 test fuel to allow 
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auto manufacturers to make calibration adjustments. While phase-in schedules or “trigger points” 

may be necessary and appropriate in some situations, we believe it would reduce complexity and 

improve market certainty to require the introduction of E15 test fuel for the 2017 model year as 

EPA has proposed. 

A specific model year requirement such as 2017 provides a 3-year lead time for vehicle design 

and calibration changes. This would also provide important certainty for fuel providers, 

marketers and distributors that a trigger point approach would not provide. Perhaps more 

importantly, implementation in the 2017 model year would eliminate the need for an interim E10 

test fuel and the related complexity and potential vehicle modifications associated with a second 

test fuel transition. 

Organization: National Marine Manufacturers Association (NMMA)

NMMA’s focus is on the EPA’s request for comment regarding changing the automotive and 

light duty truck certification fuel to E15, and perhaps higher, and its effect on boats and marine 

engines due to potential misfueling and continued availability of suitable fuel. 

The NMMA is not opposed to the use of ethanol as an additive in gasoline. Our members have 

been designing their engines and fuel systems to be compatible with E10 since the early 1980’s. 

Our very serious concern is that the 12.1 million recreational boats currently registered the 

United States, and those boats currently being manufactured, have not been designed to be 

compatible with gasoline that has ethanol content greater than 10%. Recreational marine fuel 

systems are not unique in this regard. The overwhelming majority of non-road engines, from 

chainsaws to weed trimmers to lawn mowers, operate similarly to recreational marine engines 

with open loop systems including a carburetor that is set at the factory and designed to be—and 

required by EPA to be—tamper proof. 

In addition to the well-documented physical evidence of ethanol’s damaging effects on marine 

and other non-road engines, NMMA’s concerns are also based on the physical properties of 

ethanol in gasoline. Gasoline is a mixture of many hydrocarbon compounds that consist mainly 

of hydrogen and carbon. Ethanol contains hydrogen and carbon, but it also contains oxygen. The 

exact air-fuel ratio needed for complete combustion is called the “stoichiometric air-to-fuel 

ratio.” This ratio is about 14.7 to 1 on a weight basis for gasoline that does not contain any 

ethanol. When more ethanol is added to gasoline, less air is required for complete combustion 

because oxygen is already contained in the ethanol. For example, for E10 the stoichiometric airto-fuel ratio is 14 to 14.1 pounds of air per pound of fuel. The stoichiometric air-to-fuel ratio for 

straight ethanol is 9 to 1, so as the proportion of ethanol in gasoline increases so must the air-tofuel ratio decrease. To deliver the required power for a given operating condition, engines are 

designed to consume enough air and fuel to generate the required energy. The marine engine is 

designed and calibrated to anticipate a specific fuel-to-air ratio and nothing different. Because 

ethanol blended fuels require more fuel for the same amount of air to achieve stoichiometric 

conditions, the fuel system must adapt by introducing more fuel. If additional fuel is not 

introduced to compensate for the ethanol, the resulting mixture has less fuel than needed and the 

engine experiences a condition known as “enleanment.” 
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Enleanment can lead to a variety of performance problems. For example, the combustion and 

exhaust gas temperatures will be higher, engine starting may be harder, and the engine speed 

control may become inaccurate. The increased combustion and gas temperatures resulting from 

lean operation can result in severe damage to pistons, head gaskets, catalysts and emission 

related components, which in turn may result in the failure of the engine and increased exhaust 

emissions. 

A series of engine evaluations conducted by Mercury Marine and Volvo Penta under direction of 

the Department of Energy (DOE) National Renewable Energy Laboratory (NREL) concluded 

that ethanol content in gasoline at 15% by volume will severely damage marine engines and 

cause them to exceed the EPA emission standards (1). There is no remedy for this engine 

damage and emission standard exceedances and it is not limited to recreational marine engines. 

These same issues apply to other product categories including outdoor power equipment, heavy 

duty engines, and snowmobiles. If E15 becomes the primary fuel in the US marketplace, 

misfueling will occur, EPA and California emission standards will be violated, engines will be 

damaged, and the American consumer will be stuck paying the bill for a misguided US 

government policy that needs to be corrected now. 

EPA requests comment on proposing to change the certification test fuel to E15 and supports this 

by stating that the requirements in the Renewable Fuel Standard (RFS-2) will result in E15 

becoming the predominant fuel in the US marketplace in the next 10¬15 years (78 Fed. Reg. at 

29,909.) The RFS-2 requires that the US fuel supply contain 36 billion gallons of renewable fuel 

by 2022. When the RFS-2 was created in 2007, fuel consumption in the US was rising, the 

NHSTA motor vehicle fuel efficiency standards had not been promulgated, and the US 

government had great hope for the consumer acceptance of E85. Since 2007, fuel consumption in 

the US has decreased significantly with expectations of its continued fall. E85 consumption 

reached a high of 38.6 million gallons in 2011 and consumption has remained flat since then. 

The E85 contribution to achieving the requirements in the RFS-2 is insignificant. 

E15 can never achieve the requirements of RFS-2. This proposed change to the EPA certification 

test fuel will not even come close to achieving the RFS-2 requirements. EPA would need to 

mandate E20, E25 or even E30 for all engines immediately to meet 36 billion gallons in nine 

years. Such action would not be logical or responsible. Thus, EPA is attempting to create a 

piecemeal approach to achieving a federal requirement that cannot be achieved without great 

cost to vehicle and engine owners. The RFS-2 is a broken government mandate that may have 

made sense in 2007, but does not work today. NMMA recommends that the certification fuel 

remain at E10 and that EPA formally request that Congress and the Administration amend the 

Renewable Fuel Standard to reflect America’s realistic motor fuel resources for 2013 and 

beyond. 

EPA also requests comment on a plan to allow the use of E10 as the certification test fuel with a 

transition scheme to E15 in the future (78 Fed. Reg. at 29,910). This would create far more 

confusion for consumers than an immediate mandate to E30. At this time, gasoline retailers that 

choose to sell E15 must clearly label the gasoline pump with the following specific language: 
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If E15 becomes the certification test fuel for automobiles and light trucks, it will soon be the 

primary fuel in the marketplace. Being the primary fuel in the marketplace, marine engine 

manufacturers will have to follow suit and design engines to operate on E15. However, their 

open loop engines require a fuel to air ratio for optimum combustion that is limited and far less 

able to tolerate variation in fuel oxygen content. In other words, an engine designed for 2.5% 

oxygen will not operate efficiently or meet the emission standards with a fuel containing 5% 

oxygen. 

NMMA is also concerned with consumer labeling. The current label (see above) clearly states 

that if the consumer uses E15 in any engine other than a 2001 and newer passenger vehicles, it is 

a violation of federal law. If E15 is the only available fuel in the marketplace, breaking this law 

seems inevitable. Is this violation of federal law a misdemeanor or a felony? When does the label 

come off; when does it stay on? When does it apply, when doesn’t it apply? NMMA is 

concerned that this proposal shows no consideration for the consumers who own the millions of 

lawn mowers, garden equipment, farm machinery, snowmobiles, and marine engines that will be 

damaged and no longer covered under manufacturer warranties. This automobile and light truck 

proposal will start the process of moving the nation’s fuel supply to E15 and destroying marine 

and other non-road engines in the process. 

Organization: Natural Resources Defense Council (NRDC)

The gasoline emissions test fuel should be modified to reflect typical fuel on the market, which is 

gasoline blended with 10 percent by volume of ethanol (E10). 

Gasoline Emissions Test Fuel Should be Modified to Reflect Typical Fuel on the Market (E10). 

NRDC agrees with EPA’s objective to make the emission test fuel closer to the fuel widely 

available in the market, and we support increasing the ethanol volume to 10 percent but not 15 

percent as proposed by EPA. Today the share of E15 in the gasoline market is small and the 

likely share during the implementation of the Tier 3 rule with model year 2017 and beyond is 

highly uncertain. It is conceivable that instead of reaching E15 as the majority fuel in the market, 

renewable drop-in fuels could have a significant market penetration. If drop-in fuels such as 

biobutanol capture a large share of the market, EPA would have to evaluate the need for 

subsequent changes in the test fuel to match the marketplace. 

EPA should establish a market penetration level above 10 percent for ethanol and/or drop-in 

fuels that would trigger a regulatory proceeding to establish new test fuel parameters. In 

establishing the trigger volume, EPA should consider the rate at which ethanol or other 

renewable fuel volumes are increasing in the market, the amount of time required to complete a 

rulemaking and the amount of time required for manufacturers to adopt the new fuel in their test 

procedures. The goal should be to set the trigger such that any changes to the test fuel could be 

adopted by the manufacturers when the new test fuel would be representative of the majority of 

the fuel on the market. 

Organization: New York State Department of Environmental Conservation
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We have long urged EPA to adopt emissions certification gasoline specifications that are 

representative of actual commercial gasoline. We are pleased with EPA’s steps in this direction. 

However, nearly all commercial gasoline contains nominally 10 volume percent ethanol (El 0). 

We urge EPA to adopt El 0 as the standard certification gasoline ethanol content, not the E 15 

standard proposed. 

Certification fuels should be comparable to commercial fuels. We have long urged EPA to 

change certification gasoline standards to more closely reflect commercial gasoline. Currently, 

the two have little in common. Current certification gasoline contains no ethanol, and regulations 

allow unrealistically low amounts of aromatics and olefins. 

The use of certification gasoline that reflects the properties of commercial gasoline rather than a 

‘super-clean’ certification gasoline provides additional assurance that the air quality benefits 

promised by Tier 3 are realized. We support EPA’s steps in this direction. 

10. Commercial gasoline overwhelmingly contains nominally 10 volume percent ethanol. This is 

the ethanol content that should be specified for certification gasoline. 

The Department opposes EPA’s proposal to require 15 volume percent ethanol in certification 

gasoline (E15). This is no more reflective of commercial gasoline than today’s requirement for 

zero ethanol. Allowing E15 in certification gasoline violates the principle of testing and 

certifying vehicles on a fuel that reflects the properties of commercial gasoline. E15 is not a 

significant commercial fuel now, and there is no assurance that E15 will become a significant 

commercial fuel in the future. 

Unless and until E15 becomes the dominant commercial gasoline blend, it should not be the 

certification gasoline blend. 

Organization: Northeast States for Coordinated Air Use Management (NESCAUM)

EPA should ensure that certification fuels accurately represent fuels used in the real world. In our 

view, the proposed requirement that certification fuel contain 15% ethanol by volume (E15) is 

inappropriate at this time. Given that this fuel represents a tiny fraction of the present-day fuels 

market in the U.S., that its future prospects as a mainstream automotive fuel are highly uncertain, 

and that its use in the existing fleet of vehicles will have non-trivial effects on vehicle emissions, 

we urge EPA to refrain from specifying E15 as a test fuel at this time. We suggest that EPA 

continue to monitor the use of ethanol as a blended transportation fuel. If and when E15 comes to 

represent a significant share of the national market, EPA should reassess its implications and the 

potential benefits and drawbacks to revising the test fuel specifications. 

Organization: Ozone Transport Commission (OTC)

In the past, EPA has relied upon multiple fuels that are not necessarily available at public 

gasoline dispensing facilities for use in testing vehicles to meet certification standards. OTC is 

encouraged by EPA’s decision to have one national real world test fuel. This will ensure that the 

cars on the road are indeed meeting the emission standards for which they were tested. However, 
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OTC suggests that EPA rely on current, rather than future, in-use fuel, in particular in regards to 

ethanol concentrations. Currently, E15 (15% ethanol) is available in only six states having only a 

small market share nationally due to concerns about its effects on automobiles and infrastructure 

at gasoline dispensing facilities. Furthermore, California requires E10 (10% ethanol) as a test 

fuel, which would lead to a discrepancy between vehicles tested to meet California vehicle 

standards and those tested to meet EPA standards. OTC calls on EPA to require E10 test fuel to 

maintain nationally harmonized testing standards, and only move to E15 at a point in when E15’s 

market share becomes the predominant fuel blend.

Organization: PBF Energy Inc.

PBF supports the EPA in the concept that the proposed vehicle emission test fuels should match 

the properties of fuels found typically in the market place. The EPA should revise the proposed 

rule to require that vehicle manufacturers certify emissions with E10 test fuel until such time as 

E15 is actually widely used by consumers as- opposed to a projected to be used by consumers. 

As an alternative, we recommend that the EPA defer to using the DOE/EIA projection of E15 

usage and timeline of prevalence as the inception date for allowing E15 to be used in new 

vehicle emission certification. 

Organization: Pennsylvania Department of Environmental Protection (DEP)

The EPA is correct to develop a certification test fuel for vehicles subject to Tier 3 standards that 

is more representative of the fuel that is used in the nation. DEP has urged EPA to change the 

certification fuels to represent a real-world fuel on other proposed rulemakings. DEP supports 

EPA moving to a fuel that is more representative of the fuel available to the nation’s motorists. 

In the future, EPA should make timely changes to the certification fuel as relevant changes occur 

to fuels available in the marketplace. 

The EPA should not use a certification test fuel that contains 15 volume percent ethanol before 

that fuel is in widespread use in the nation. DEP questions whether there is sufficient ethanol 

supply to meet the 15 volume percent threshold when Tier 3 goes into effect. The ethanol 

industry reports that 20 of 211 biofuel plants are currently idled and many more are not 

producing at capacity. If the current drought in the Midwest continues into the summer of 2013 

(which the National Oceanic and Atmospheric Administration predicts), some ethanol plants will 

likely be shut down permanently. Current annual biofuel production is at least 5 billion gallons 

per year short of demand predicted in the EPA’s proposed rule. The certification fuel should 

include 10 volume percent ethanol until over 50 percent of the fuel supplied to the nation’s 

motorists meets the 15 volume percent ethanol requirement. In addition, CARB will be using 10 

volume percent ethanol in their certification fuel. The federal fuel certification requirements 

should be harmonized with CARB’s requirements. Importantly, as previously stated, ethanol 

increases NOx emissions and the increase to 15 volume percent of ethanol in gasoline seems to 

be counter to the desire to achieve NOx reductions through the use of Tier 3 gasoline. 

Organization: Phillips 66 Company
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Certification fuel – We oppose E15 as the certification fuel. Phillips 66 does not support the 

proposed change in the certification test fuel to E15. The certification fuel should be reflective of 

the predominant fuel in the marketplace that the vehicle will be operated on. EPA states “if E15 

were not to enter the gasoline pool in significant quantities, it may be more appropriate to require 

that vehicles be calibrated for and tested on E10”. We believe that the certification fuel should be 

E10 and not E15. EPA asked for comment on an approach that would set the test fuel at E10 but 

potentially transition to E15 in the future, either through a review and rulemaking process or by 

some “trigger”. Should EPA determine in the future that another change in the certification fuel 

is warranted, we believe that EPA should go through a rulemaking process. We would not 

support an automatic “trigger” without opportunity to review and comment through a rulemaking 

process. 

Organization: POET, LLC

The Tier 3 Proposed Rule appropriately recognizes that ethanol blending is of central importance 

to our nation’s transportation fuel supply and accomplishing key environmental and energy 

security goals. To achieve these goals and maintain a robust domestic transportation fuel supply, 

it is critical that EPA design its regulations to facilitate the production, blending, and use of 

ethanol as a transportation fuel. 

Ethanol already provides about 10% of the fuel for our nation’s cars and trucks. Indeed, most 

fuel available today contains 10% ethanol in every gallon distributed at the pump. EPA has 

recently approved blends of 15% ethanol (E15) for over 230 million vehicles on the road today 

(those that are model year 2001 and later). Additionally, over 14 million flexible-fueled vehicles 

(FFVs) are on the road that can run on gasoline and blends containing up to 85% ethanol.

Ethanol is also inherently less toxic than petroleum fuels. Clean-burning ethanol is essentially 

comprised of alcohol with a small amount of denaturant to render it unsuitable for drinking. 

Ethanol use enables key air emission reductions of particulate matter, benzene, sulfur, and other 

toxic constituents as compared to gasoline. In fact, ethanol itself contains no benzene, generally 

no sulfur, and overall has significantly lower air emissions than gasoline on a toxicity-weighted 

basis. 

The continued use of E10 and the increased use of E15 are critical to our nation’s energy supply 

and environmental goals. 

To summarize, POET strongly supports two key certification fuel provisions in the Proposed 

Rule. In particular, POET supports both the ‘E15’ base certification fuel, as well as an optional 

E30 certification fuel. It is also imperative that RVP limits must not be a barrier to the use of 

higher ethanol blends. 

POET supports EPA’s proposed E15-based certification fuel. 

EPA proposes a new certification fuel that would be applicable to conventional gasoline 

vehicles, including those that run on ethanol blends up to E15. This new certification fuel is 

proposed to include an ethanol content of 15%. 
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POET strongly supports a new certification fuel based on an ethanol content of 15%. POET 

agrees with EPA that such a fuel is a ‘better match’ for fuels in use today (which generally have 

an ethanol content of at least 10%) than the current certification fuel that contains no ethanol. 

Moreover, such a certification fuel is appropriate considering the increased use of E15 over the 

next few years. EPA is correct in pursuing a ‘forward-looking E15 test fuel for light- and heavyduty gasoline vehicles,’ and an E15 certification fuel better reflects the near future. EPA notes 

that ‘In-use fuel is projected to continue to change with the implementation of the RFS2 

program’ including with ‘the expansion of the number of retailers that offer E15.’ POET agrees. 

The RFS2 obligations mandate increasing amounts of renewable fuel, the majority of which is 

likely to be ethanol. Furthermore, the percentage of gasoline use from vehicles on the road that 

are capable of using E15 (including model years 2001 and newer) is greater than 70% and is 

growing as new vehicles replace aging ones. 

An E15 certification fuel is preferable to an E10 certification fuel because an E10 certification 

fuel may become obsolete in the timeframe covered by this rulemaking. Moreover, EPA has 

sought to have vehicles tested with the highest available ethanol content that reflects actual 

driving conditions; for conventional ‘gasoline’ vehicles, this would be an ethanol content of 

15%. 

Moreover, without enabling E15 use, EPA would be frustrating the will of Congress in enacting 

the RFS, and EPA must adhere to regulatory requirements that it act to ‘ensure’ that RFS targets 

are met. Congress has mandated that EPA ‘promulgate regulations to ensure that gasoline’

contains the applicable volumes specified in the RFS. An E15 certification fuel is necessary for 

the RFS targets to be met in the short term, by allowing for the deployment of vehicles that can 

best make use of (are optimized for) this fuel. 

E15 should also become the prevalent fuel in the marketplace for compatible vehicles (model 

year 2001 and newer) given ethanol’s inherent economic advantages as a blendstock and octane 

enhancer.

Organization: Renewable Fuels Association (RFA)

RFA supports the proposal to establish E15 as the certification test fuel beginning in 2017. RFA 

supports EPA making much needed modifications to the certification fuel used by auto 

manufacturers in certifying all new vehicles. Significant changes in the composition of the in-use 

gasoline available to consumers have taken place since the initial new vehicle certification 

requirement circa 1974. 

RFA strongly supports moving to a certification fuel that contains the highest level of ethanol 

that is likely to be in broad commercial use in the next 5-10 years. In light of EPA’s recent 

approval of E15 for use in light-duty automobiles built in 2001 or later, and the recent 

introduction of E15 at retail gasoline stations in several states, we agree that E15 is the proper 

new certification fuel beginning in 2017. The agency should be mindful, however, that RFS2 

requirements and the increasing desire for higher octane fuels to maximize engine efficiency are 

likely to drive average ethanol content above 15% over the course of the next 10 years. 
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Looking at certification fuel another way, EPA could align the emissions certification fuel with 

the diurnal emissions test fuel containing ethanol in at least the highest concentration permissible 

in gasoline under federal law and that is commercially available. Further, EPA should include an 

incentive for auto manufacturers who phase in the certification of new vehicles with the new 

certification fuel ahead of the prescribed schedule for implementation. Early adoption of the new 

certification fuel will accelerate the capability of the national car pool with higher ethanol 

blended fuels. 

Organization: Shell Oil Products for Shell and Motiva

EPA Should Change the Vehicle Certification Fuel to E10. EPA is proposing to change the 

vehicle certification fuel to E15. We agree it is appropriate for EPA to change the vehicle 

certification fuel from the current E0, since over 90% of all gasoline in the United States is now 

blended with ethanol, but believe that EPA should change it to E10 rather than E15. As required 

by section 202(h) of the Clean Air Act, EPA’s regulations should require that the certification 

fuel reflect the fuel that is generally available in the market. Section 202(h) required EPA to 

update its regulations to ensure that “vehicles are tested under circumstances which reflect the 

actual current driving conditions under which motor vehicles are used, including conditions 

relating to fuel, temperature, acceleration, and altitude.” As this relates to fuel, it clearly calls for 

EPA to use E10, not E15 as the certification fuel. 

It is unlikely that E15 use will expand to the degree that EPA suggests in the proposal. EPA fails 

to consider that notwithstanding its approval of E15, the automobile manufacturers do not 

support E15 use in the current fleet and E15 is not compatible with the infrastructure at the 

majority of retail gasoline stations. Studies by the Coordinating Research Council also indicate 

that E15 can damage even 2001 and newer vehicles. 

Organization: Sierra Club, Clean Air Watch, Respiratory Health Association

As EPA notes in the proposed standards, in-use gasoline has changed significantly in previous 

decades. With the implementation of the Renewable Fuel Standard, most gasoline sold contains 

up to 10% ethanol by volume (E10). In the proposed rule, EPA proposes moving from Indolene 

to an E15 test fuel. Additionally, EPA is proposing to allow manufacturers to request approval 

for alternative certification fuel, such as E30. 

However, ethanol blends higher than E10 are not widely available in the market today. Though 

EPA recently increased the “blend wall” to E15, that fuel has not been widely adopted yet, and 

significant concerns have been raised about the effect of higher ethanol blends on older vehicles 

and small engines. By proposing E15 as a test fuel and blends such as E30 as an alternative test 

fuel, EPA is moving ahead of what is happening in the marketplace. 

Instead of proposing E15 as a certification fuel, EPA should instead adopt a certification fuel that 

is closer to real-world conditions, such as E10. It is critical that this test fuel requirement be 

harmonized with test fuel requirements for other vehicle standards, particularly light-duty 

greenhouse gas and fuel economy standards, as increased ethanol blends affect fuel economy. 
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Though test fuel conditions may need to be updated in the future, EPA should strive to match 

real-world fuel conditions. 

Organization: Truck and Engine Manufacturers Association (EMA)

EPA has proposed changing on-highway certification test fuel to E15 with a 9 psi RVP. (78 Fed. 

Reg. at 29825.) In addition, EPA requests comment on the potential to utilize E10 rather than the 

proposed E15 certification test fuel with a transition scheme to E15 at a future time. (78 Fed. 

Reg. at 29914.) Finally, EPA suggests that if it were to adopt an E10 certification test fuel, that 

fuel would have a maximum of 10 psi RVP rather than the 9 psi RVP maximum proposed for 

E15 certification test fuel. (78 Fed. Reg. at 29895.) 

EPA’s proposed changes in certification test fuel for heavy-duty vehicles up to 14,000 lbs. 

GVWR would constitute a substantial change from current certification test fuel requirements. 

EPA has not provided support in the Proposed Rule for any such change. EPA acknowledged in 

the Proposed Rule that its previous Tier 2 regulations do not apply to Heavy- Duty Vehicles 

(8,501-14,000 lbs. GVWR). Yet, EPA now has proposed that such vehicles be subject not only to 

more stringent emission standards, but also to a change in certification test fuel. In fact, EPA 

previously determined that E15 certification fuel would not be appropriate or acceptable for use 

in Heavy-Duty Vehicles (i.e., vehicles over 8,500 lbs. GVWR) (see reference below). To make 

such a change in certification test fuel for Heavy-Duty Vehicles, EPA must first fully review, 

analyze and make a new determination that E15 is acceptable for Heavy-Duty Vehicles, which it 

has failed to do. EMA does not support such a change. 

EMA also strongly objects to any attempt to create a transition scheme where products would be 

certified on E10 test fuel for the near term and transitioned to certification utilizing an E15 test 

fuel at an unspecified future date. In addition, EPA should not adjust the maximum RVP based 

on ethanol content, as such a change would have the effect of increasing the stringency of the 

new standards. 

EMA recognizes that current Heavy-Duty Vehicles are compatible with E10 marketplace fuels. 

As such, if EPA makes any change to certification test fuels for Heavy-Duty Vehicles, EPA, at 

most, should adopt E10 certification test fuel with a maximum of 9 psi RVP for Tier 3 HeavyDuty Vehicles and the engines used in them. 

Adopt E10 certification test fuel with a 9psi RVP for light-duty and medium-duty vehicles 

subject to the Proposed Rule, with future rulemakings to make similar changes to the test fuels 

for other heavy-duty and nonroad spark-ignition engines 

Organization: Union of Concerned Scientists (UCS)

EPA should adopt a certification fuel that accurately reflect the fuels used in the marketplace 

now and in the timeframe of the vehicles’ useful lifetime. The certification fuel should be chosen 

to accurately reflect the fuels used in the marketplace now and in the timeframe of the vehicles’

useful lifetime. Today the fuel most commonly in use is E10, so this is an appropriate choice for 

a certification fuel. But the fuel market is changing, and is expected to continue to change, and 
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EPA should ensure that the choice of certification fuel is, to the extent possible, technology 

neutral, and does not present a barrier to the use of the higher levels of biofuel called for in the 

Renewable Fuels Standard. Technical guidance from automakers, fuel producers and other 

experts will be required to assess the best course forward, and to determine the pros and cons of 

E15, E85, midlevel blends such as E30, or drop-in biofuels as a compliance pathway for the 

RFS. We are not in position at this point to judge the outcome of these considerations in detail. 

However, we urge that in performing this assessment EPA use realistic volume targets for the 

RFS, particularly in the timeframe from 2016 to 2022. We have provided comments in an RFS 

rulemaking explaining that the original RFS2 schedule targeting 36 billion gallons in 2022 is no 

longer realistic, because of the limited availability of cellulosic biofuels (11). More plausible 

timeframes for meeting the full 36 billion gallon target of the RFS are closer to 2030 than 2022, 

and because of this there is time for an orderly transition to higher biofuel blends as the 

cellulosic biofuel industry scales up. Any introduction of new fuel blends into commerce should 

be conducted in a manner that will protect consumers from inadvertently damaging their 

vehicles. 

Organization: United Steelworkers Union (USW)

One concern our union does have with the proposed rule is the EPA’s test fuel specification. 

EPA has indicated a desire to move from “Indolene” (E0) to an E15 test fuel. While updating the 

federal emissions test fuel to better match today’s in-use gasoline is an appropriate approach, 

specific issues regarding the “blend wall” and E15 still need to be addressed. USW would 

recommend that test fuels meet what is the predominant fuel available at fuel stations in the US. 

Our Response:

In the NPRM, EPA proposed that the gasoline emissions test fuel be changed from E0 to 

E15 as a forward-looking position based on indications following the 2011 E15 waiver decision 

that the market would move in that direction. Since the time when we developed the proposal, 

several relevant factors have led EPA to reconsider that position, including minimal proliferation 

on a national scale of stations offering E15. The most recent surveys of the market show that 

E10 now comprises nearly 100% of in-use gasoline, with very small amounts of E0 and E15 

being sold in limited areas where there is specific interest.32 Adopting an E15 test fuel would 

also complicate the regulatory streamlining goal of long-term harmonization of the Tier 3 vehicle 

emission regulations with California’s LEVIII program (which uses E10 for emissions testing).

We received comments supporting use of E10 as emissions test fuel from the automotive 

and oil industries, as well as states, NGOs, and private citizens citing the fact that this was most 

representative of current market conditions. Other stakeholders involved in fuel marketing and 

distribution cited significant infrastructure cost and liability concerns in making E15 widely 

available at existing stations. Some commenters expressed the concern that inclusion of ethanol 

in test fuel would indicate an improper EPA policy preference for ethanol over other biofuels. 

Ethanol industry commenters generally supported E15 certification fuel as proposed, but 

provided no specific timeline on which this blend level would become representative of in-use 

fuel. 

 

32 More detail on fuel survey data is available in Chapter 3 of the Regulatory Impact Analysis.
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Based on our review of the data and comments and under our authority in section 206 of 

the Clean Air Act, specifically including section 206(d), EPA has determined that E10 most 

appropriately reflects in-use gasoline around the country today and into the foreseeable future, 

and thus we are finalizing E10 as the ethanol blend level for gasoline emissions test fuel for Tier 

3 light-duty and heavy-duty gasoline vehicles. (Test fuel for motorcycles and nonroad engines is 

not changing at this time.) We are not at this time adopting any specific timeline or criteria for 

considering a gasoline emissions test fuel based on a higher-level ethanol blend. Instead we will 

continue to monitor the in-use gasoline supply, including the qualities of E15 in-use, and based 

on such review may initiate rulemaking action to revise the specifications for emissions test fuel. 

At this time it would not appear necessary to take further action to consider market triggers to 

transition automatically to E15 as an emissions test fuel as opposed to through a new rulemaking 

process. Rather than speculate about what in-use fuel qualities might be in the future, we prefer 

to see how E15 properties develop as it expands into the market.

Some commenters expressed concern about implications for future test programs, fuel 

waiver approvals, or Part 79 fuel registrations resulting from a change in test fuel properties. 

While we recognize these interactions may occur, we believe the change in emission test fuel is 

warranted to ensure that the certification process more appropriately reflects in-use conditions

Some comments included in this section also pertain to the RVP level of emission test 

fuel, a topic to which we respond in Chapter 4.5.1.2 of this document. 

Some comments included in this section also pertain to evaporative durability or service 

accumulation fuel, a topic to which we respond in Chapter 4.3 of this document. 

Some comments included in this section also pertain to allowances for alternative 

emission test fuel, a topic to which we respond in Chapter 4.5.1.5 of this document.

4.5.1.2. Emission Test Fuel RVP

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Automakers support updating certification test fuels in Tier 3 regulations, as California did in its 

recent LEV III rulemaking. EPA has asked for comment on adopting certification gasoline 

containing 10 percent ethanol with a 10 psi Reid Vapor Pressure (RVP). We have further 

discussion on the ethanol content in our fuels comments below; however, we cannot and do not 

support Tier 3 if EPA adopts a certification gasoline with an RVP of 10 psi. The proposed 

evaporative emission standards are already extremely challenging to meet across all the required 

vehicle sizes based on the 9 psi fuel proposed by EPA. An RVP of 10 psi would significantly 

increase the stringency of these standards, and we are not confident that the evaporative 

standards could be met with such fuel. Moreover, adopting a certification gasoline with an RVP 

of 10 psi would eliminate several years of work by the EPA, ARB, and automakers to harmonize 
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the Tier 3 and LEV III requirements and make them equal in stringency. While it might be 

possible to make test procedure changes for an equivalent stringency on the higher RVP, such 

changes would require years of additional work by EPA, ARB, and automakers and, even then, 

would be more likely to result in confusion and uncertainty than in equivalence. Automakers 

support a Tier 3 test fuel with 10 percent ethanol and RVP of 9 psi.

While EPA has used typical or average values for a number of the specific properties for the 

proposed Tier 3 test fuel, the Agency has made exceptions to its market representative approach 

for sulfur and RVP. In the case of sulfur, EPA is proposing more stringent market gasoline 

average sulfur limits, so the test fuel sulfur levels appropriately reflect this change. However, in 

the case of test fuel RVP, EPA is setting the level to reflect the maximum allowable content 

rather than representative market levels. Although 10 psi RVP fuels are in use in the market as a 

result of the statutory 1 pound waiver, a 9 psi RVP limit for both an E10 test fuel and 

summertime market gasoline is a better outcome for advanced vehicle technologies and for the 

environment, as detailed below. 

As noted above in Part I, the auto industry supports harmonization of Federal Tier 3 and 

California LEV III vehicle emission programs, to allow use of one test fuel and test regime to 

certify for both Tier 3 and LEV III purposes. Toward that end, while there are differences 

between these standards, we continue to support permanent mutual reciprocity to allow OEMS to 

use one test fuel and its related testing regime per test vehicle, either LEV III or Federal Tier 3, 

for purposes of both Federal and California certification. Such reciprocity is appropriate for all 

test fuels, not just gasoline. 

U.S. gasoline is now supplied as E10 in virtually all markets. The summer RVP for this fuel 

varies from 7 to 10 psi, depending on local regulations and marketers. California recently 

finalized new E10 7 psi RVP certification fuel (LEV III), based on the market fuel prevalent in 

California. As noted above, the Alliance and Global Automakers recommend that EPA set the 

Tier 3 test fuel ethanol level at 10% (E10), which represents over 90% of U.S. gasoline. 

Likewise, we deem it critical that EPA set the test fuel Reid Vapor Pressure (RVP) at no greater 

than 9 psi, which is toward the high end of the allowed range, but which appeared as the 75th 

percentile of the U.S. samples in the 2012 Alliance North American Fuels Survey (excluding 

California).

We understand that an E10 9 psi RVP cert fuel would be acceptable to California for purposes of 

mutual reciprocity certification. Transitioning to an E15 test fuel incorporates speculative 

assumptions that are not justified for the foreseeable future as a basis for such a critical 

regulatory decision. 

EPA cannot and should not try to compensate by imposing an RVP for the certification test fuel 

that results in more stringent emission tests for vehicles. This is not a legitimate replacement for 

fulfilling its duty under the Congressional mandate to regulate market fuel RVP. EPA should use 

9 psi RVP test fuel in a final Tier 3 rule, until it has had the opportunity to complete its 

evaluation of RVP regarding market fuel, and if necessary, then review RVP of test fuel. 
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Tier 3 Test Fuel Gasoline Should Be 9 psi RVP. Vapor pressure is the most important property 

for engine start-up performance. At higher ambient temperatures, the fuel can vaporize 

prematurely prior to reaching the injectors, disrupting the fuel flow to the engine and creating 

“vapor lock.” As defined in ASTM D4814, vapor lock conditions arise “if too much vapor is 

formed, the fuel flow to the engine can be decreased, resulting in loss of power, rough engine 

operation, or engine stoppage.” During cold ambient temperatures, fuels with vapor pressures 

that are too low can prevent the engine from starting at all or have poor warm-up performance. 

Thus, the vapor pressure and distillation profile of gasoline are controlled based on seasonal 

ambient temperatures so that fuel vaporizes easily (higher vapor pressure) in cold weather to 

assist in engine starting, and vaporizes less easily (lower vapor pressure) in warm weather to 

prevent vapor lock and reduce evaporative emissions.

ASTM D4814, Standard Specification for Automotive Spark-Ignition Engine Fuel, specifies for 

Class A fuel a 9 psi maximum for the continental U.S. during the summer low-VOC (Volatile 

Organic Compound) RVP blending season. The 10 psi market gasoline in some conventional 

markets is largely due to Congressional action. Enacted in part to increase the volume of 

renewable fuels in the U.S. marketplace, the Energy Policy Act of 2005 and the Energy 

Independence and Security Act of 2007 have greatly increased the penetration of E10 in the 

market. Under section 211(h) 4 of the CAA, these E10 blends are allowed an additional 1 psi of 

vapor pressure relative to conventional gasoline or other ethanol blends. 

EPA states in the NPRM (26): While the volatility (i.e., RVP) of CARB’s E10 test fuel is 7.0 psi 

to be representative of in-use gasoline in California during summer months, conventional E10 in 

the rest of the country is currently around 10 psi. Thus, should we finalize E10 instead of E15, in 

the absence of any standard to reduce the in-use RVP of E10 to 9.0 psi or lower, we would also 

have to consider raising the RVP of certification test fuel to 10 psi to reflect the RVP level of the 

current in-use fuel.

EPA should not raise the test fuel RVP to 10 psi. Inspection of the 2010-2012 Alliance of 

Automobile Manufacturers Summer fuel surveys for US States (excluding Alaska, Hawaii and 

California data) in Figure 1 [Figure 1 can be found on p. 55 of Docket number EPA-HQ-OAR2011-0135-4461-A1.pdf] show that the 50th percentile of samples is an 8 psi fuel while 10 psi is 

only found at the 95th percentile of samples. 9 psi would be approximately the 75th percentile of 

samples. Thus a 9 psi E10 fuel would be a realistic market fuel representation when considering 

an E10 certification fuel.

But for the one pound waiver, E10 would be 9 psi or lower, which it is in many parts of the 

country. As discussed further below, for both vehicle performance and environmental benefits, 

we advocate that EPA reduce market fuel RVP to 9 psi (including 8 psi with a 1 pound waiver to 

9 psi for E10). Therefore, it would be consistent to use a 9 psi test fuel. We disagree that there is 

any technical basis or policy reason for imposing a 10 psi test fuel. Requiring the use of a 10 psi 

test fuel would have the effect of making the Tier 3 evaporative emissions tests more stringent 

for vehicles than anticipated, more stringent than California, and would disrupt optimal 

harmonization efforts.

EPA should make the final Tier 3 gasoline test fuel E10 9 psi RVP. 
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HDGV and 10 PSI: Industry opposes 10 psi RVP test fuel for use in evaporative emission 

testing. The use of a 10 psi test fuel would impact the stringency of the evaporative emission 

standards and prevent a single national harmonized emissions program 

E10 & 10 PSI (FR29910): Industry opposes a 10 PSI test fuel. This impacts the stringency of the 

Tier 3 evap standards and does not harmonize with the ARB LEV III program. 

Organization: American Coalition for Ethanol (ACE)

Volatility/Reid Vapor Pressure (RVP) — EPA is proposing to change the Federal certification 

test fuel specification to a 9 RVP gasoline with 15% ethanol, and while we could support such a 

change, it again seems inconsistent with past practices and with EPA’s goal of having test fuel 

more accurately reflect the fuels available in the marketplace. The highest volume fuel in the 

U.S. is 10 lb. RVP E10. [EPA-HQ-OAR-2011-0135-4313-A2 p. 3]

Organization: American Lung Association

We believe that if the Reid Vapor Pressure (RVP) of E10 in current in-use fuel is 10 psi, then the 

certification fuel should also be 10 psi. 

Organization: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

The test fuel vapor pressure should be set at 10 psi dry vapor pressure to reflect the 1 psi waiver 

afforded to fuels containing 9% to 10% ethanol found in the Clean Air Act. 

Organization: California Air Resources Board (CARB)

RVP 10 fuel implications for evaporative emission testing: The NPRM requests comment for 

alternatively requiring E10 with Reid Vapor Pressure (RVP) of 10 psi rather than E15 with an 

RVP of 9 psi for certification emissions testing. Regardless of which fuel U.S. EPA finalizes for 

Tier 3, CARB strongly recommends that U.S. EPA maintain an equivalent level of stringency for 

evaporative emission testing with LEV III evaporative emission standards. If equivalency 

between Tier 3 and LEV III evaporative requirements is maintained, CARB intends to accept test 

data from vehicles tested using Tier 3 certification fuel and temperatures to meet the LEV III 

evaporative emission requirements. See also our more detailed comments on Tier 3 certification 

fuel on pages 21-22 of this document. 

Comment 1 — Gasoline Certification Test Fuel: CARB recommends that the U.S. EPA 

reconsider the use of E15 as the Tier 3 certification fuel. Instead, CARB recommends a 

certification fuel with 10 percent volume ethanol (E10) and a 9.0 pounds per square inch (psi) 

RVP. An E10 certification fuel would be consistent with the current federal commercial fuel. In 

addition, the 9.0 psi RVP would allow the Tier 3 program and California’s LEV III program to 

be consistent with the certification fuel reciprocity precedent set between the Tier 2 program and 

California’s LEV II program. The evaporative emission difference between U.S. EPA’s 9.0 psi 

RVP Tier 2 certification fuel and California’s LEV II 7.0 psi RVP certification fuel was offset by 
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U.S. EPA’s use of a lower diurnal temperature range. California’s LEV III certification fuel has 

approximately a 7.0 psi RVP and CARB staff recommends that U.S. EPA maintain a 9.0 psi 

RVP fuel such that the evaporative emission offsets between the California LEV III certification 

fuel and the Tier 3 certification fuel can be maintained. 

Organization: Chrysler Group LLC

The certification test fuel for gasoline-fueled vehicles should be an E10, 9.0 psi RVP test fuel, 

rather than an E15 certification test fuel. 

Reid Vapor Pressure of Certification Test Fuel: Chrysler recommends that EPA set the 

certification test fuel RVP at 9.0 psi rather than the 10.0 psi proposed by EPA for E10 fuel. RVP 

is a measure of the volatility of gasoline. Because gasoline evaporates more readily the higher 

the RVP, use of a higher RVP fuel for evaporative emissions testing imposes a more difficult 

compliance burden on automobile manufacturers (18). Indolene, the current certification test 

fuel, has an RVP of 9.0 psi. EPA proposes to retain this 9.0 psi RVP if E15 is adopted as the 

certification test fuel. However, EPA proposes to raise the RVP from 9.0 psi to 10.0 psi should it 

instead adopt E10 as the certification test fuel. EPA states that raising the RVP to 10.0 psi for 

E10 fuel is necessary in order to be representative of conventional E10 gasoline. [EPA-HQOAR-2011-0135-4326-A2, p. 7]

EPA’s reasoning that it is necessary to raise the RVP for E10 certification test fuel is flawed 

(21). Although it is true that conventional E10 gasoline can have an RVP of up to 10.0 psi during 

summertime months, it is not the case that E10 gasoline with an RVP of 10.0 psi is 

representative of in-use fuel. Rather, 9.0 psi fuel is most representative of in-use fuels. First, 

many states require use of reformulated gasoline, which has a lower RVP than conventional E10 

gasoline in the 7.0 to 8.0 psi range. In fact, according to EPA, reformulated gasoline is currently 

used in 17 states and the District of Columbia, and accounts for approximately 30 percent of 

gasoline sold in the United States (22). In addition, although conventional E10 gasoline can as a 

statutory matter have an RVP of up to 10.0 psi, some conventional E10 gasoline has an RVP that 

is lower than 10.0 psi. Thus, as explained in comments provided by the Alliance of Automobile 

Manufacturers, 9.0 psi fuel represents the 75th percentile RVP level of U.S. gasoline in 

summertime months based on samples collected as part of the 2012 Alliance North American 

Fuels Survey (excluding California, Alaska, and Hawaii, which have even lower RVP levels) 

(23). Accordingly, 9.0 psi fuel is actually more representative of in-use fuel than 10.0 psi fuel 

and thus is more appropriate for use as the certification test fuel. [EPA-HQ-OAR-2011-0135-

4326-A2, pp. 7-8]

Organization: Ford Motor Company (Ford)

EPA has proposed a new Tier 3 certification test fuel containing 15% ethanol (E15) with a Reid 

Vapor Pressure (RVP) of 9psi. While the percentage of ethanol in the proposed fuel does not 

match that of the 10% ethanol (E10) fuel adopted by California in LEV III, the proposed vapor 

pressure ensures equivalent stringency with respect to evaporative emissions when this fuel is 

used with the temperatures specified in EPA evaporative test procedures. However, in the NPRM 

EPA also explored the ramifications of instead proposing an E10 test fuel, indicating that such a 
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change could result in an RVP other than 9 psi. Ford strongly opposes any increase in the RVP 

of the test fuel since this would require either heavily modified test procedures or higher 

standards in order to maintain equivalent stringency to CA LEV III.

Recommendation: Ford recommends that EPA adopt a 9 psi test fuel to maintain equivalent 

stringency with CA LEV III and to ensure that the Tier 3 evaporative emissions standards are 

achievable. [EPA-HQ-OAR-2011-0135-4349-A2,p.3]

Organization: General Motors LLC (GM)

Although not proposed by EPA, throughout the Tier 3 NPRM, EPA discusses the possibility of a 

10 psi (pounds per square inch) Reid Vapor Pressure (RVP) test fuel for evaporative emission 

testing. GM is strongly opposed to the use of 10 psi test fuel for evaporative emission testing. 

GM has vast experience conducting evaporative emission testing with both CARB 7 psi and EPA 

9 psi test fuels. The Tier 3 regulations were intended to harmonize with the CARB LEV III 

regulations and to propagate zero evaporative emission vehicle technologies across the nation. 

GM vehicle designs are predicated on the understood equivalent performance between the EPA 

and CARB test procedures and test fuels. Moving to a 10 psi test fuel would decouple this basic 

design premise, destroy the reciprocity agreement between EPA and CARB and would represent 

a significant stringency increase for vehicles complying with the Tier 3 requirements. Simply 

put, Tier 3 would not be harmonized with LEV III, and the goal of a single national program 

would be undermined. 

While EPA has used typical or average values for a number of the specific properties to define 

their proposed test fuel, the Agency made exceptions to its market representative approach for 

sulfur and RVP. In the case of sulfur, EPA is proposing to impose more stringent market 

gasoline average sulfur limits, so the test fuel sulfur levels appropriately reflect this change. 

However, in the case of test fuel RVP, EPA is setting the level to reflect the maximum allowable 

rather than representative market levels. Although 10 psi RVP fuels are in use in the market as a 

result of the statutory 1 pound waiver, a 9 psi RVP limit for both an E10 test fuel and 

summertime market gasoline is a better approach for advanced vehicle technologies and for the 

environment, as detailed below. [EPA-HQ-OAR-2011-0135-4288-A1, p.11 ] 

U.S. gasoline is supplied with E10 in virtually all markets. The summer RVP for this fuel varies 

from 7 to 10 psi, depending on local regulations and markets. California recently finalized new 

E10 7 psi RVP certification fuel (LEV III) based on the market fuel prevalent in California. GM 

recommends that EPA set the Tier 3 test fuel ethanol level at 10% (E10) which represents over 

90% of U.S. gasoline. [EPA-HQ-OAR-2011-0135-4288-A1, p.12] 

Likewise, we deem it critical that EPA set the test fuel RVP at no greater than 9 psi, which is 

toward the high end of the allowed range, appearing in the 75th percentile of the U.S. samples in 

the 2012 Alliance North American Fuels Survey (excluding California).8 This is discussed 

further in Section XV. [EPA-HQ-OAR-2011-0135-4288-A1, p.12] 
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In conversations with members of CARB, an E10 9 psi RVP certification fuel would be 

acceptable to California for purposes of mutual reciprocity certification. [EPA-HQ-OAR-2011-

0135-4288-A1, p.12] 

Tier 3 Gasoline Certification Test Fuel Should Be 9 psi RVP: Vapor pressure of gasoline is the 

most important property for engine start-up performance. At higher ambient temperatures, the 

fuel can vaporize prematurely prior to reaching the injectors, disrupting the fuel flow to the 

engine and creating “vapor lock”. As defined in ASTM D4814, vapor lock conditions arise “if 

too much vapor is formed, the fuel flow to the engine can be decreased, resulting in loss of 

power, rough engine operation, or engine stoppage.” During cold ambient temperatures, fuels 

with vapor pressures that are too low can prevent the engine from starting at all or cause it to 

have poor warm-up performance. Thus, the vapor pressure and distillation profile of gasoline is 

controlled based on seasonal ambient temperatures so that fuel vaporizes easily (higher vapor 

pressure) in cold weather to assist in engine starting and vaporizes less easily (lower vapor 

pressure) in warm weather so as to prevent vapor lock and reduce evaporative emissions. [EPAHQ-OAR-2011-0135-4288-A1, p.15]

ASTM D4814, Standard Specification for Automotive Spark-Ignition Engine Fuel, specifies for 

Class A fuel a 9 psi maximum for the continental U.S. during the summer low-VOC (Volatile 

Organic Compound) RVP blending season. The 10 psi market gasoline that EPA sees in some 

conventional markets is largely due to Congressional action. Enacted, in part, to increase the 

volume of renewable fuels in the U.S. marketplace, the Energy Policy Act of 2005 and the 

Energy Independence and Security Act of 2007 have greatly increased the penetration of E10 in 

the market. Under section 211(h) 4 of the Clean Air Act, these E10 blends are allowed an 

additional 1 psi of vapor pressure relative to gasoline or other ethanol blends.[EPA-HQ-OAR2011-0135-4288-A1, p.15]

EPA states in the NPRM, “While the volatility (i.e., RVP) of CARB’s E10 test fuel is 7.0 psi to 

be representative of in-use gasoline in California during summer months, conventional E10 in 

the rest of the country is currently around 10 psi. Thus, should we finalize E10 instead of E15, in 

the absence of any standard to reduce the in-use RVP of E10 to 9.0 psi or lower, we would also 

have to consider raising the RVP of certification test fuel to 10 psi to reflect the RVP level of the 

current in-use fuel.” [EPA-HQ-OAR-2011-0135-4288-A1, p.15]

We disagree that there is any technical basis or policy reason for imposing a 10 psi test fuel. 

Requiring the use of a 10 psi test fuel would have the effect of making the Tier 3 evaporative 

emissions tests far more stringent for vehicles than anticipated, and far more stringent than 

California LEV III, completely undermining the harmonization efforts. Further, making 

certification fuel have a vapor pressure of 10 psi would have the effect of making this high vapor 

pressure summer gasoline permanent. [EPA-HQ-OAR-2011-0135-4288-A1, p.16]

EPA cannot and should not try to compensate for the widespread use of ethanol by imposing an

RVP for the certification test fuel that results in more stringent emission tests for vehicles. This 

is not a legitimate replacement for fulfilling its congressionally mandated duty to regulate market 

fuel RVP. EPA should use 9 psi RVP test fuel in the final Tier 3 rule. [EPA-HQ-OAR-2011-

0135-4288-A1, p.17]
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Inspection of the 2010-2012 Alliance of Automobile Manufacturers summer fuel surveys for 

U.S. States (excluding Alaska, Hawaii and California data) in Figure 1 show that the 50th 

percentile of samples is an 8 psi fuel while 10 psi is the 95th percentile of samples. 9 psi would 

be approximately the 75th percentile of samples. Thus, a 9 psi E10 fuel would be a realistic 

market fuel representation when considering an E10 certification fuel. [[See Docket Number 

EPA-HQ-OAR-2011-0135-4288-A1, p.16 for Figure 1.]]

Organization: Marathon Petroleum Company LP (MPC)

The test fuel vapor pressure should be set at 10 psi dry vapor pressure to reflect the 1 psi waiver 

afforded to fuels containing 9% to 10% ethanol found in the Clean Air Act.

Organization: Michigan Department of Environmental Quality (MDEQ)

The MDEQ, Air Quality Division is supportive of a change to the emission test fuel 

specifications to E-10 as long as this revision is accompanied by a Reid Vapor Pressure (RVP) of 

9.0 pounds per square inch (psi). As an ozone compliance strategy, many of the large 

metropolitan areas throughout the country are required to use reformulated gasoline or fuels with 

lower RVP limits than the 10.0 psi claimed to reflect fuels in conventional use. The test fuel 

should be reflective of what is widely used in the marketplace, especially large urban areas 

where there is high traffic volume. 

Organization: Mitsubishi Motors R&D America, Inc (MRDA)

EPA requested comments on a proposal for Federal E10, 10 psi RVP certification fuel. 

Additionally, Tier 3 evaporative emissions standards are proposed to align with LEV III 

standards. Though there are differences in the Federal and California test procedure temperature 

profiles to account for the climatic differences, proper specification of Federal and California 

certification fuels – specifically RVP – makes the results equivalent. It is commonly known that 

9 psi RVP ‘Federal’ fuel using Federal evaporative test procedures yields similar test results as 7 

psi RVP California fuel using California procedures. Therefore, the use of a 10 psi RVP federal 

certification fuel will no longer allow for harmonized evaporative emissions standards. Clearly, 

this issue is caused by the statutory one pound waiver that allows market availability of 10 psi 

RVP fuel as a temporary regulatory mechanism. Therefore, creating a long-term certification fuel 

should not be based on a temporary waiver. [EPA-HQ-OAR-2011-0135-4281-A1, p.2]

Mitsubishi Motors emphasizes that permanent reciprocity of certification test fuel with the LEV 

III program should not include a fuel with an RVP higher than 9 psi RVP. Federal certification 

fuel higher than 9 psi RVP would result in significant challenges in meeting the Tier 3 

evaporative emission standards. The lack of harmonization in this area leads to an increased 

development burden upon automotive manufacturers because they need to account for possible 

higher vehicle engineering costs, redundant-testing, and increased costs due to additional test 

fuel stock. We request that EPA focus on incorporating a permanent reciprocity regime with 

Federal E10, 9 psi RVP fuel and federal test procedures into the Tier 3 Final Rule in order to 

follow through on its goal to harmonize with LEV III. Doing so would follow the 
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Administration’s call for ‘smart regulations’ by eliminating areas of duplicative and unnecessary 

compliance requirements. [EPA-HQ-OAR-2011-0135-4281-A1, p.2]

EPA should not consider a federal certification test fuel higher than 9 psi RVP. [EPA-HQ-OAR2011-0135-4281-A1,p.2]

Organization: National Automobile Dealers Association (NADA)

EPA should not approve E15 as a test fuel given its lack of presence in the marketplace and 

should not mandate a test fuel above 9 psi RVP. 

To enable Tier 3 evaporative emissions compliance, a Reid Vapor Pressure (RVP) cap should be 

set at 9 psi for a maximum E10 gasohol test fuel. 

Organization: National Corn Growers Association (NCGA)

We concur with EPA’s proposed 9 psi vapor pressure specification for an E15 test fuel. The 

current vapor pressure specification for Tier 2 vehicles is also 9 psi. However, we recommend 

that in-use ethanol blends between E11-50 be allowed a 1 psi waiver, as applied to E10. Our 

rationale is further discussed within the In-Use Fuel section of these comments. We do not 

believe that a 1 psi waiver for E11-E50 necessitates a vapor pressure specification greater than 9 

psi for E15 certification fuel, any more than E10 (which has a 1 psi waiver) does for the current 

certification gasoline. Reformulated Gasoline (RFG) areas and non-RFG areas without a waiver 

currently have less than 9 psi fuel in the summer; vapor pressure greater than 9 psi only occurs in 

non-RFG areas with a waiver. EPA did not propose further volatility controls for in-use fuel as a 

part of the Tier 3 fuel requirements. If EPA were concerned about the emission increases of Tier 

3 (or even Tier 2) vehicles certified on 9 psi fuel and operated on 10 psi in the summer, it would 

have done so as a part of its fuel proposal. [EPA-HQ-OAR-2011-0135-4285-A1, p. 4]

EPA points out in the Tier 3 proposal that vapor generation in motor vehicles using 10 psi fuel in 

the summer is 25% higher than with 9 psi fuel. However, this does not mean that vehicle 

emissions are increased by 25% because modern vehicle evaporative emission control systems 

are designed to capture emissions for a 3-day park at high temperatures. The Tier 3 evaporative 

emission standards represent a very high level of evaporative emission control, whether the 

vehicles are operated on 9 psi fuels or in some areas of the country, 10 psi. [EPA-HQ-OAR2011-0135-4285-A1, p. 4]

Organization: National Marine Manufacturers Association (NMMA)

EPA requests comment regarding the option of allowing the use of CARB E10 certification test 

fuel through model year 2019 with a Reid Vapor Pressure (RVP) of 10 psi (78 Federal Register 

29895). EPA currently provides a 1 psi waiver for E10, but this waiver will not apply to E15. 

NMMA recommends that the 1 psi waiver also be eliminated for E10. EPA finalized a rule in 

2010 that requires boat builders to meet stringent new evaporative emission requirements. 

California is currently in the process of finalizing a rule. In order to meet these new emission 
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standards, marine engine manufacturers need a combination of new technology and a fuel with a 

minimum evaporation rate. [EPA-HQ-OAR-2011-0135-4294-A1, p. 4]

Organization: New York State Department of Environmental Conservation

Certification gasoline Dry Vapor Pressure Equivalent should reflect worst case commercial 

summer conventional gasoline. Currently certification gasoline has a nominal Reid Vapor 

Pressure (RVP) of 9 psi. EPA’s proposed certification gasoline standard has a nominal Dry 

Vapor Pressure Equivalent (DVPE) of 9 psi. These are the same except for a change in test 

method (and acronym). While a 9 psi standard is appropriate for E0 or E15 gasoline, it is not 

appropriate for a certification gasoline standard based on current commercial practice. 

In much of the country conventional summer gasoline DVPE is nominally 10 psi through a 

combination of Clean Air Act Section 211(h)(1)’s summer gasoline maximum RVP of 9 psi and 

the 1 psi waiver for E10 contained in Section 211(h)(4). As long as this remains the case, it is the 

worst case for evaporative emissions, and is what evaporative emission control systems should 

be designed for and certified on. 

Organization: Phillips 66 Company

The test fuel specifications for an E10 test fuel should align with the ASTM gasoline 

specification, D4814. EPA stated that they reviewed refinery test data as one input to set 

specifications for various test fuel properties. Currently, all conventional gasoline is tested and 

reported to EPA on a clear basis so would not include the effect of the blended ethanol that is 

added downstream. A few notes on selected properties: [EPA-HQ-OAR-2011-0135-4463-A1, p. 

7]

- Vapor pressure should be set at 10 psi which accounts for the 1 psi vapor pressure waiver 

allowed for E10 blends throughout most of the United States [EPA-HQ-OAR-2011-0135-4463-

A1, p. 7]

Organization: Revecorp Inc.

First, the proposed TIER 3 rule states that testing for evaporative emissions will be conducted on 

fuel which is lower RVP than the current certification fuel. Unfortunately, at a time which EPA 

is proposing decreasing the RVP of the certification fuel may, in-use vehicles are being exposed 

to higher RVP fuel. For example, it is possible that because E85 is being sold and more flexible 

fuel/E85 capable vehicles are in the fleet that a vehicle could end up with a high RVP fuel in the 

tank. For instance, if a motorist had than the certification fuel is a good possibility. For example, 

if an E85 vehicle is refueled with 19 gallons of E10 fuel when it had one gallon of E85 in the 

tank, the ethanol content of the resulting fuel would be 13.75%, near the highest RVP of any 

gasoline/ethanol blend, and with an RPV much higher than the new proposed certification fuel. 

Vehicle testing should be performed with fuel which is representative of the fuel which vehicles 

are expected to see under the most severe in-use conditions. 

Organization: Truck and Engine Manufacturers Association (EMA)
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Adopt E10 certification test fuel with a 9psi RVP for light-duty and medium-duty vehicles 

subject to the Proposed Rule, with future rulemakings to make similar changes to the test fuels 

for other heavy-duty and nonroad spark-ignition engines 

Organization: Volkswagen Group of America, Inc.

VW strongly supports capping both market fuel and testing fuel at 9 psi RVP. This allows 

current vehicles to operate their evaporative emissions controls more efficiently. An immediate 

real-world air quality benefit will be soon in non-attainment areas that typically see 10 psi RVP 

summertime fuels. A 10 psi RVP test fuel will unnecessarily increase the stringency of the Tier 3 

evap rule. Since CARB does not view a 10 RVP E10 test fuel as equivalent to their gasoline test 

fuel for LEVIII, a 10 RVP fuel walks further away from a harmonized National Program. 

Our Response:

In addition to our proposal to change the ethanol level of gasoline emission test fuel, we 

raised the question of which volatility level (or RVP) would be most appropriate. The Clean Air 

Act Section 211(h)(1) sets a national limit on summertime RVP in northern conventional 

gasoline areas of 9.0 psi to control ozone pollution. However, Congress included a waiver 

allowance in Section 211(h)(4) granting an additional 1 psi RVP to 10% ethanol blends, meaning 

that E10 could have an RVP of up to 10 psi in conventional gasoline areas unless specifically 

prohibited by state or local rules. (Under Section 211(h)(4), E15 is not covered by the waiver 

and thus is restricted to 9 psi nationwide.) 

Some commenters, including some automakers, recommended leaving the RVP of 

emissions test fuel at 9 psi for reasons including the fact that raising the specification to 10 psi 

would increase the stringency of the proposed evaporative emission standards significantly. We 

agree that the resulting increased vapor generation rates during the refueling test would increase 

emissions (by about 10 percent and during the hot soak, diurnal, canister bleed, and running loss 

tests by as much as 25 percent in total). While the likely increase in canister volume in response 

to higher certification fuel RVP would not be difficult for automakers to accommodate in most 

cases, there are additional uncertainties regarding cost and feasibility of strategies for removing 

the larger vapor loads from the canister during vehicle operation (vapor “purging”). Some 

vehicles have adequate engine vacuum available to accomplish the increased vapor purge, while 

others may require new or innovative approaches to increase purge volume or efficiency 

(discussed in more detail in preamble Section IV.C.3). 

Several other commenters, including some NGOs and environmental groups, supported 

setting certification gasoline RVP to 10 psi to be representative of the worst-case volatility 

vehicles may see in the market, making the test procedure more stringent than in the proposed 

program and likely bringing further evaporative emission reductions in-use. 

Raising the certification test fuel RVP to 10 psi would also impact the equivalency of 

CARB and EPA evaporative emission test procedures. EPA and CARB have maintained a 

reciprocity agreement regarding test fuel RVP and test temperatures for hot soak plus diurnal and 

running loss emissions since the mid 1990’s. (California requires the use of 7 psi RVP test fuel, 

which, in conjunction with higher test temperatures, produces equivalent results to the federal 
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test procedures using 9 psi fuel for purposes of evaporative control system design.) CARB has 

accepted ORVR emission test results using Federal test fuels and test temperatures since the 

1998 model year. If we were to adopt 10 psi test fuel, we would likely need to develop and 

adopt new test procedure adjustments in order to maintain the equivalency of CARB and EPA 

evaporative procedures (and allow reciprocal acceptance of test data generated under either 

agency’s program). 

A review of 2011 gasoline batch data submitted to EPA shows that just under half of 

summertime gasoline was conventional gasoline at 10 psi RVP. An additional third was 

reformulated gasoline at approximately 7 psi, with the remainder having intermediate RVPs 

under local volatility control programs. The volume-weighted average RVP of this data is 

approximately 8.7 psi. Thus, approximately half of summertime gasoline falls above 9 psi and 

half falls below, suggesting an emissions test gasoline with RVP of 9 psi aligns well with in-use 

fuel nationwide. In addition, virtually all of the areas that have elevated summertime ozone 

levels where excess evaporative VOC emissions would be of greatest concern already control inuse gasoline RVP to levels less than 9 psi. Furthermore, under CAA Section 211(a)(5), 

governors can request that the 1 psi waiver for E10 not apply in their state if it causes an 

emissions increase that contributes to air pollution. Any state exercising this authority would 

have in-use E10 RVP levels limited to 9 psi.

After considering these technical and policy issues in the context of the available data and 

comments received, we conclude that the most appropriate approach is to maintain the RVP at 9 

psi for Tier 3 emissions test fuel. 

Some comments included in this section also pertain to the ethanol level of emission test 

fuel, a topic to which we respond in Chapter 4.5.1.1 of this document. 

Some comments included in this section also pertain to the RVP of in-use gasoline, a 

topic to which we respond in Chapter 4.5.1.6 of this document. 

Some comments included in this section also pertain to properties of emission test fuel 

for flexible fuel vehicles (FFVs), a topic to which we respond in Chapter 4.5.2 of this document.

4.5.1.3. Test Fuel Octane

What Commenters Said:

Organization: American Coalition for Ethanol (ACE)

Octane — EPA recommends reducing test fuel octane to around 87 (R+M)/2, to be 

representative of in-use fuel, and plans to continue to allow manufacturers to test vehicles on 

premium-grade gasoline should vehicles require it. EPA also plans to continue to allow 

exceptions for lower-volatility fuel for high altitude testing. There has never been a requirement 

that manufacturers prove that premium would actually be used by the operator of a premiumonly vehicle if that certification method is chosen. The high-altitude exception has been offered 
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although most vehicles will rarely have that kind of fuel available and if ever operate at high 

altitude. The current test fuel is not available commercially in any gas stations. 

EPA asks whether there should be a maximum octane of gasoline used in certification. ACE 

conversely suggests that there should be a minimum octane for the base fuel, so that refiners 

cannot continue to control ethanol in the marketplace by simply creating lower-octane, lowerquality blendstocks or ‘BOBs’ each time ethanol percentage is increased. This refiner practice 

prevents automakers from using of ethanol’s higher octane to make cleaner vehicles. While EPA 

has been unfairly charged with ‘picking winners and losers’ through its rules, failing to maintain 

a minimum octane for base fuels would effectively allow the oil industry to ‘pick winners and 

losers,’ by allowing refiners to retain full control of octane offered by ethanol and other 

additives, by creating BOBs that swallow all of that octane value before it can reach vehicles and 

consumers. [EPA-HQ-OAR-2011-0135-4313-A2 p. 2-3]

EPA must maintain high standards for octane, especially because future GHG emissions 

reductions proposed by the Agency on automakers are very likely to lead to advanced vehicle 

technologies (turbocharging, downsizing, increasing compression ratios, etc) that require and 

indeed optimize on clean and high-octane qualities that fuel ethanol delivers. Failing to require 

higher octane or to protect minimum octane allows choices to be dictated by the petroleum 

industry. 

To update certification fuel with high-octane ethanol but propose to reduce - or even simply 

maintain - overall octane seems inconsistent. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Automakers support EPA’s proposed option for use of premium grade octane gasoline as test 

fuel, consistent with California LEV III. 

Organization: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

EPA proposes to change the measurement approach from RON to AKI and lower the octane 

requirement to be consistent with regular unleaded fuel at 87.0 (R+M)/2. EPA also proposes to 

allow manufacturers to test on a fuel with a minimum octane rating of 91 (R+M)/2 for those 

vehicles where operation on high-octane gasoline is required by the manufacturer. EPA is 

seeking comment on the need for limiting the maximum octane of gasoline used in the 

certification of premium-required engines and vehicles. As we will note in other comments, EPA 

needs to limit the range of certification fuels to those that are readily found in the marketplace. 

As such, a high-octane fuel specification should be limited to 91 (R+M)/2. While higher octane 

fuels exist in the marketplace, they are not available on a nation-wide basis and several 

significant regions offer 91 (R+M)/2 premium gasolines as the highest level available. These 

regions include California, Arizona and Nevada where a significant number of premium vehicles 

are sold by the manufacturers. Increasing the minimum octane of premium to satisfy these 

vehicles and support their certification would add significantly to the cost of this regulation. 
Tier 3 Summary and Analysis of Comments

4-269

Another related issue is the requirements that would need to be put on the vehicles to insure that 

only premium fuel is used in these vehicles. Will there be a requirement for special nozzles? Will 

the “Check Engine” light illuminate? This special accommodation makes no sense unless EPA 

has some way of insuring that this fuel is used in the field if it is required for emissions or other 

regulatory performance attributes (e.g., CAFE compliance). Finally, if a consumer fills a 

“premium” vehicle with regular, does that constitute misfueling? 

The octane level for high altitude test fuels is not mentioned in the text, but rather shown in 

Table IV-21, where EPA is proposing that the octane be set at 87.0 minimum (R+M)/2. Market 

fuels in high altitude regions currently meet an 85 minimum (R+M)/2; we question the need to 

raise the octane for the high altitude certification fuel if EPA is indeed looking “to better match 

today’s in-use fuel”. Again, increasing the minimum octane to satisfy these vehicles and support 

their high altitude certification would add significantly to the cost of this regulation. 

Organization: Biotechnology Industry Organization (BIO)

BIO urges EPA against lowering octane as it allows for higher biofuel content in the emissions 

test fuel in order to further help meet its air quality and public health goals, as well as to help 

incentivize automakers and help them meet their CAFE requirements for model vehicles 2017 

and beyond. Instead, BIO suggests EPA issue a final Tier 3 rule that maximizes investment in 

biofuels, while also encouraging the highest achievable level of octane in transportation fuel. 

Ethanol and other alcohol fuels including butanol, for instance, have higher octane ratings than 

neat fuel. Higher octane enables higher compression and more efficient combustion engines. It 

could actually boost fuel economy in future car models, according to a 2009 report by Sandia 

National Labs, if automakers concentrate on developing smaller engines with higher 

compression and turbocharging. For this reason, encouraging higher octane could help 

incentivize automakers to make cars that run on cleaner fuel. 

High octane blends including ethanol offer a means for auto manufacturers to meet higher 

mileage CAFE standards. In fact, during EPA’s recent public hearing on Tier 3, Mercedes Benz 

publically announced its support for the Tier 3 proposed emissions test fuel and urged adoption 

of higher blends including E25. And last year, the Alliance for Automobile manufacturers filed 

comments to EPA stressing the need to transition to higher blends. 

Organization: Chevron Products Company

Similar to CARB, EPA proposes to provide for both 87 and 91 anti-knock index (AKI) 

certification fuels. This provides a base certification fuel that more closely matches AKI of the 

currently predominant in-use fuel, while providing a mechanism for vehicle manufacturers to 

utilize the benefits of a higher octane fuel if they so choose. This plan provides a good balance 

between OEM flexibility and recognition of customer choice. However, the specification for the 

‘Premium’ certification fuel should include a maximum AKI limit in order to ensure certification 

on a similar octane to that which may be encountered in-use. 

Organization: Growth Energy
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Growth Energy also recognizes ethanol’s important octane contribution to the nation’s fuel 

supply. As it relates to the proposed E15 certification fuel, we feel that it is crucial that any 

additional octane achieved by adding ethanol should not be lost by making lower-octane gasoline 

blendstocks (CBOB and RBOB). As such, Growth Energy believes that a higher octane level 

certification fuel would be more reflective of in-use octane levels of E15 fuels. Specifically, we 

recommend a base octane level of 88.5 - 90 [(R+M)/2]. 

Organization: INEOS Bio

INEOS Bio urges EPA against lowering octane as it allows for higher biofuel content in the 

emissions test fuel in order to further help meet its air quality and public health goals, as well as 

to help incentivize automakers and help them meet their CAFÉ requirements for model vehicles 

2017 and beyond. Instead, INEOS Bio suggests EPA issue a final Tier 3 rule that encourages the 

highest achievable level of octane in transportation fuel. 

Ethanol has a high octane rating and is cleaner burning and more cost effective than the 

petroleum based octane equivalent. Higher octane enables higher compression and more efficient 

combustion engines. It could actually boost fuel economy in future car models, according to a 

2009 report by Sandia National Labs, if automakers concentrate on developing smaller engines 

with higher compression and turbocharging. For this reason, encouraging higher octane could 

help incentivize automakers to make cars that run on cleaner fuel. 

High octane blends of ethanol offer a means for auto manufacturers to meet higher mileage 

CAFÉ standards. In fact, during EPA’s recent public hearing on Tier 3, Mercedes Benz 

publically announced its support for the Tier 3 proposed emissions test fuel and urged adoption 

of higher blends including E25. And last year, the Alliance for Automobile manufacturers filed 

comments to EPA stressing the need to transition to higher blends. A higher octane Tier 3 fuel 

that includes >E15 is needed in order for these engines to meet the new CAFÉ standards for 

2017 and beyond. 

Organization: Marathon Petroleum Company LP (MPC)

EPA proposes to change the measurement approach from RON to AKI and lower the octane 

requirement to be consistent with regular unleaded fuel at 87.0 (R+M)/2. EPA also proposes to 

allow manufacturers to test on a fuel with a minimum octane rating of 91 (R+M)/2 for those 

vehicles where operation on high-octane gasoline is required by the manufacturer. EPA is 

seeking comment on the need for limiting the maximum octane of gasoline used in the 

certification of premium-required engines and vehicles. As we will note in other comments, EPA 

needs to limit the range of certification fuels to those that are readily found in the marketplace.

As such, a high-octane fuel specification should be limited to 91 (R+M)/2. While higher octane 

fuels exist in the marketplace, they are not available on a nation-wide basis and several 

significant regions offer 91 (R+M)/2 premium gasolines as the highest level available. These 

regions include California, Arizona and Nevada where a significant number of premium vehicles 

are sold by the manufacturers. Increasing the minimum octane of premium to satisfy these 

vehicles and support their certification would add significantly to the cost of this regulation. 

Another related issue is the requirements that would need to be put on the vehicles to insure that 
Tier 3 Summary and Analysis of Comments

4-271

only premium fuel is used in these vehicles. Will there be a requirement for special nozzles? Will 

the “Check Engine” light illuminate? This special accommodation makes no sense unless EPA 

has some way of insuring that this fuel is used in the field if it is required for emissions or other 

regulatory performance attributes (e.g. CAFE compliance). Finally, if a consumer fills a 

“premium” vehicle with regular, does that constitute misfueling? 

The octane level for high altitude test fuels is not mentioned in the text, but rather shown in 

Table IV-21, where EPA is proposing that the octane be set at 87.0 minimum (R+M)/2. Market 

fuels in high altitude regions are currently meeting an 85 minimum (R+M)/2 and so we question 

the need to raise the octane for the high altitude certification fuel if EPA is indeed looking “to 

better match today’s in-use fuel”. Again, increasing the minimum octane to satisfy these vehicles 

and support their high altitude certification would add significantly to the cost of this regulation.

Organization: National Automobile Dealers Association (NADA)

Lastly, a minimum 87 AKI octane rating should be specified. 

Organization: National Corn Growers Association (NCGA)

The second principle is that ethanol blends above E10 should be splash blended to increase 

octane above the level of 87 Anti-Knock Index (AKI). This will provide higher-octane fuels (not 

higher priced “premium” grade fuels) to be widely used by the motoring public and by the 

automakers in meeting the 2017 and Later Model Year Light-Duty Vehicle GHG and Corporate 

Average Fuel Economy (CAFE) Standards. 

Ethanol has a high octane value which has allowed gasoline refiners to supply gasoline 

blendstock for blending with ethanol at levels significantly below 87 AKI, typically 84, such that 

the finished gasoline meets the 87 octane minimum requirement. Virtually all E15 sold at retail 

today is made using the same 84 AKI octane base gasoline, resulting in a higher blended octane 

in the range of 88.5 to 90 AKI. EPA has proposed an 87 to 88.4 octane range for Tier 3 test fuel. 

We believe the E15 certification fuel octane should reflect the octane of retail E15, ensuing that 

the octane value of ethanol will continue to be used to raise the octane of finished gasoline above 

87 AKI. Our recommendation is that EPA establishes an octane range of 88.5 to 90 AKI for E15. 

This would also be consistent with an incremental improvement in fuel economy and GHG 

emission performance of modern vehicle electronic emission control systems to this increase in 

octane. 

Organization: POET, LLC

POET supports a base certification fuel octane level above 88.4. As part of proposing an updated 

certification fuel (based on E15), EPA proposes lowering the specified based gasoline octane to 

87.0-88.4 (R+M)/2 ‘to be representative of in-use fuel, i.e., regular-grade gasoline.’ (26) POET 

suggests that an octane of 88.5-90 (approximately 1.5 points higher) would more likely reflect 

in-use octane levels for an E15 certification fuel, and an even higher octane range may be 

appropriate. Indeed, as vehicle manufacturers move toward downsized and turbocharged 
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engines, octane levels of in-use fuels are likely to increase. As noted above, a recent MathPro 

refinery study found that increasing the fuel octane to 92 AKI from 88 AKI would result in 

significant cost savings.

Our Response:

Since more than 80% of the gasoline consumed in the U.S. is regular grade E10 gasoline 

with an AKI of approximately 87, we proposed changing the octane rating of emission test fuel 

to 87-88.4 AKI. This is also consistent with CARB’s LEV III gasoline test fuel specifications.[1]

Manufacturers can continue to use high-octane gasoline (with a minimum octane rating of 91 

AKI) for testing of premium-required[2] vehicles and engines as well as for testing unrelated to 

exhaust emissions. (Comments related to the expected AKI levels of E15 in-use are no longer 

relevant since we are finalizing E10 test fuel.) 

Regarding establishing an upper limit for the octane range of premium test fuel, we have 

decided to mirror CARB’s approach of no upper limit (California is an area where lower-octane 

premium fuels are likely to be found in-use). Further, manufacturers will design their premium 

fuel required vehicles for the minimum octane market premium fuel which as discussed by 

commenters is 91 AKI and any additional octane will not impact the emission performance of 

the vehicle. Because of this, we do not feel it is necessary to constrain the certification test fuel 

upper limit which would likely add additional cost to the certification test fuel. 

An 85 AKI test fuel was not specified for high altitude regular gasoline because modern 

spark ignition vehicles are designed and optimized for octane levels around the typical regular 

grade of 87 AKI, and this is typically stated in the owner’s manual. (In the case of mid-grade or 

premium-required vehicles, the higher octane specification is for all altitudes.) While these 

modern vehicles can compensate for octane levels less than the manufacturer’s design intent, this 

typically results in loss of performance and can cause an increase in GHG and other emissions. 

Thus, it did not seem necessary or prudent to specify an additional unique test fuel with lower 

octane specifications for emission testing at high altitude when manufacturers recommend or 

require a minimum of 87 AKI or higher for the majority of their modern vehicles. 

Some comments we received on the octane specification for emissions test fuel focused 

on the need for in-use fuels to have higher octane and/or ethanol content. Those commenters 

appear to have misunderstood the purpose of the change in emission test fuel specifications. 

EPA is using its Clean Air Act section 206 authority to establish requirements for emission 

certification testing, including specifications of the emissions test fuels with which vehicles 

demonstrate compliance with emissions standards, in order to better reflect the ethanol content 

and other properties of in-use fuels. While we are taking action to limit sulfur content in in-use 

gasoline under authority in Clean Air Act sections 211(c)(1) and (2), we did not propose other 

changes to in-use fuels. Any action related to changing the octane level of in-use gasoline is 

outside the scope of this rulemaking. 

 

[1] LEV III test procedures, including a description of test fuel, can be found at 13 CCR 1961.2.

[2] Premium-required defined at §1065.710(d).
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Some comments included in this section also pertain to the octane level of in-use fuel, a 

topic to which we respond in Chapter 4.5.1.6 of this document. 

4.5.1.4. Other Test Fuel Specifications

What Commenters Said:

Organization: American Coalition for Ethanol (ACE)

Aromatics — We support reductions in aromatics such as benzene and note that EPA 

acknowledges in the NPRM that has ethanol blending has increased due to the RFS, harmful 

levels of aromatics in gasoline have declined by nearly twenty percent over the last decade. E15 

and other high-level ethanol blends will continue to help reduce aromatics further. Further, there 

is a growing body of evidence that shows that mid-level ethanol blends (i.e., E30) result in even 

greater reductions in aromatics and resulting improvements in air quality and improved health 

for U.S. citizens. We know that the Urban Air Initiative is submitting a detailed set of comments 

on this particular point that deserve careful consideration by EPA. 

Organization: Growth Energy

With the addition of ethanol, it may also be necessary to lower aromatics, benzene and specific 

distillation temperature limits. ASTM Standard D4814 uses a T50 distillation temperature range 

of 150 – 190 degrees, while EPA proposed a T50 distillation temperature range of 170-190 

degrees. EPA should lower the lower end of the temperature range to be consistent with the 

ASTM standard. Growth Energy also agrees that additional ethanol use can, and should, lower 

total aromatics, and that should be reflected in the E15 certification fuel accordingly. 

Organization: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

In addition to ethanol content, EPA proposes to make changes to several other certification fuel 

characteristics. API and AFPM recommend consistency between certification fuel standards and 

the industry recognized standard for gasoline developed by ASTM International: ASTM D4814. 

API and AFPM provide detailed comments relating to certification fuel octane, distillation 

temperatures, sulfur, aromatics, olefins, aromatics distribution, and the test methods used by 

laboratories to determine these characteristics. 

The specifications of the test fuel should match up with the specifications set by ASTM in 

D4814. To match up to ASTM D4814 the following changes should be made: 

The T50 minimum distillation temperature should be 150 F for E10. The proposed T50 

temperature of 170 to 190 F is too high given the boiling point depression caused by the 

formation of an azeotrope between the hydrocarbons and the ethanol. Addition of the ethanol 

depresses the T50 point by 20 to 350 F. 
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EPA proposes to adjust the gasoline distillation temperatures to better reflect today’s in-use 

gasoline / E10. We question EPA’s approach to determining market fuel quality levels as they 

“relied heavily on the AAM North American Fuel Survey trends” which are limited in scope and 

confounded by lumping all fuel grades in to one analysis. EPA also used 2009 refinery 

compliance data to assist in setting specifications. Using more recent data, and to be consistent 

with ASTM specifications, we believe EPA should revisit the distillation properties with 

suggested T10 in the range of 110°F to 130°F and more importantly a relaxation of the minimum 

T50 to 150°F. 

EPA is proposing to lower the sulfur content of the test fuel to 8-11 ppm to be consistent with the 

proposed Tier 3 standards. We cover comments on acceptability in the technical justification 

section of these comments (section I.A). 

EPA is proposing to reduce the aromatics content to better match today’s in-use gasoline/E10. 

As stated before, EPA is using limited AAM data and historic refinery compliance data to 

support their conclusion on market fuel quality. In addition, Figure 3-4 in the RIA shows refinery 

batch data for olefin levels and not aromatics. Based on our own data analysis, average aromatics 

content for E10 blends during the past two summer seasons was 25 volume percent. 

Similar to aromatics, average olefin content for E10 blends during the past two summer seasons 

was 9 volume percent. 

EPA is proposing to include a distribution of aromatics in the certification fuel to ensure that it is 

more representative of in-use gasoline. We do not have recent data on composition distributions 

for aromatics in market fuel but would note the sum of the distributed aromatics maximum is less 

than the “Total Aromatic Hydrocarbons” maximum (24.4 versus 24.5). 

EPA proposes to update some of the gasoline test procedures which we encourage them to do, 

noting that some of the procedures may not be appropriate for E15 test fuels (e.g. D525 does not 

include E15). We also suggest EPA use the latest versions of the following tests: D2699, D2700, 

D5191, D86, D5453, D3237, D130, D381, and D512 as these all have 2012 releases. 

From an overall standpoint, we would recommend that EPA consider moving to an E10 regular 

unleaded certification fuel that adequately describes the current in-use fuel quality while also 

ensuring enough severity that Tier 3 emissions standards provide substantive emissions changes 

versus Tier 2. To that end we would suggest the following key certification fuel properties: 

Ethanol Content 9.8 to 10.2 volume %

Octane 87 to 88.4 (R+M)/2

DVPE 9.7 to 10.2 psi

T10 110°F to 130°F

T50 150°F to 170°F

T90 310°F to 330°F

FBP 380°F to 420°F

Aromatics 21.5 to 26.5 volume %

Olefins 6 to 12 volume %
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Finally, EPA should indicate that the certification test fuel properties should in no way be 

interpreted as limiting for in-use fuels. Rather the narrow range of fuel properties provides 

consistency for EPA and industry when evaluating results from standard emissions tests and 

other certification test programs. 

Organization: Chevron Products Company

The proposed specifications that define the distribution of aromatics in the certification fuel 

appear to be overdone. This level of detail will encourage certification fuel blenders to blend 

near-pure components rather than more typical refinery streams. EPA and others have identified 

examples of test programs in which fuel blends that used atypical refinery streams to blend test 

fuels produced atypical emissions results. The proposal should be dramatically simplified, at a 

minimum. 

Organization: Chrysler Group LLC

EPA should adopt low sulfur market, refiner and retailer gasoline fuel. 

Organization: Mercedes-Benz USA, LLC on behalf of Daimler AG

The primary factors which directly impact the Mercedes-Benz GHG Compliance Plan are sulfur 

content in market fuel, and ethanol content and octane level in certification and market fuel. 

Organization: INEOS Bio

We applaud the EPA for efforts in the Tier 3 proposal to reduce sulfur to 10ppm, change the 

emissions test fuel to E15 and encourage flexibility to allow for even higher blends, however 

there were indications that the EPA intended to address the issue of aromatics and higher 

minimum octane requirements, but this does not appear to be the case. As a cellulosic ethanol 

producer, INEOS Bio would like to further highlight the benefits of higher ethanol blends and 

how they can compliment and even improve upon the proposed Tier 3 requirements. 

Organization: Marathon Petroleum Company LP (MPC)

Test fuel specifications should be consistent with ASTM D4814. The specifications of the test 

fuel should match up with the specifications set by ASTM in D4814. To match up to ASTM 

D4814 the following changes should be made:

The T50 minimum distillation temperature should be 150 F for E10. The proposed T50 

temperature of 170 to 190 F is too high given the boiling point depression caused by the 

formation of an azeotrope between the hydrocarbons and the ethanol. Addition of the ethanol 

depresses the T50 point by 20 to 35 F. 
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EPA proposes to adjust the gasoline distillation temperatures to better reflect today’s in-use 

gasoline / E10. We question EPA’s approach to determining market fuel quality levels as they 

“relied heavily on the AAM North American Fuel Survey trends” which are limited in scope and 

confounded by lumping all fuel grades in to one analysis. EPA also used 2009 refinery 

compliance data to assist in setting specifications. Using more recent data, and to be consistent 

with ASTM specifications, we believe EPA should revisit the distillation properties with 

suggested T10 in the range of 110°F to 130°F and more importantly a relaxation of the minimum 

T50 to 150°F. 

EPA is proposing to lower the sulfur content of the test fuel to 8-11 ppm to be consistent with the 

proposed Tier 3 standards. We cover comments on acceptability in the technical justification 

section of these comments (section I.A). 

EPA is proposing to reduce the aromatics content to better match today’s in-use gasoline/E10. 

As stated before EPA is using limited AAM data and historic refinery compliance data to support 

their conclusion on market fuel quality. In addition, Figure 3-4 in the RIA shows refinery batch 

data for olefin levels and not aromatics. Based on our own data analysis, average aromatics 

content for E10 blends during the past two summer seasons was 25 volume percent. 

Similar to aromatics, average olefin content for E10 blends during the past two summer seasons 

was 9 volume percent. 

EPA is proposing to include a distribution of aromatics in the certification fuel to ensure that it is 

more representative of in-use gasoline. We do not have recent data on composition distributions 

for aromatics in market fuel but would note the sum of the distributed aromatics maximum is less 

than the “Total Aromatic Hydrocarbons” maximum (24.4 versus 24.5). 

EPA proposes to update some of the gasoline test procedures which we encourage them to do, 

noting that some of the procedures may not be appropriate for E15 test fuels (e.g. D525 does 

not include E15). We also suggest EPA use the latest versions of the following tests: D2699, 

D2700, D5191, D86, D5453, D3237, D130, D381, and D512 as these all have 2012 releases. 

From an overall standpoint, we would recommend that EPA consider moving to an E10 regular 

unleaded certification fuel that adequately describes the current in-use fuel quality while also 

ensuring enough severity that Tier 3 emissions standards provide substantive emissions changes 

versus Tier 2. To that end we would suggest the following key certification fuel properties:

Ethanol Content 9.8 to 10.2 volume %

Octane 87 to 88.4 (R+M)/2

DVPE 9.7 to 10.2 psi

T10 110°F to 130°F

T50 150°F to 170°F

T90 310°F to 330°F

FBP 380°F to 420°F

Aromatics 21.5 to 26.5 volume %

Olefins 6 to 12 volume %
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Finally, EPA should indicate that the certification test fuel properties should in no way be 

interpreted as limiting for in-use fuels. Rather the narrow range of fuel properties provides 

consistency for EPA and industry when evaluating results from standard emissions tests and 

other certification test programs. 

Organization: New York State Department of Environmental Conservation

In addition to setting the ethanol content of certification gasoline at 10 volume percent, EPA 

should specify a T50 range consistent with the norms reported on E10 batch reports. We note 

that, except for T50, the certification gasoline distillation curve proposed by EPA lines up quite 

well with data from New York’s 2011 and 2012 gasoline sampling program for summer 

conventional gasoline. 

Minimum requirements for certification gasoline aromatics and olefins content, and a realistic 

distribution of aromatics should be promulgated as proposed. 

Current federal certification gasoline standards have no minima for olefins and aromatics. This 

allows gasoline with unrealistically ‘clean’ properties to be used for vehicle certification and 

testing. The Department strongly supports EPA’s proposal to specify ranges (minimum and 

maximum) for aromatics and olefins that are based on actual gasoline production batch reports. 

Equally important is EPA’s proposal to require a realistic distribution of aromatics by carbon 

number. 

These changes will ensure that vehicle development, certification, and compliance testing is 

conducted on a fuel that reflects the composition of commercial gasoline. Although we can’t 

quantify emissions benefits, we expect that this will lead to more effective emissions control 

systems and real world air quality benefits. 

Organization: Phillips 66 Company

The test fuel specifications for an E10 test fuel should align with the ASTM gasoline 

specification, D4814. EPA stated that they reviewed refinery test data as one input to set 

specifications for various test fuel properties. Currently, all conventional gasoline is tested and 

reported to EPA on a clear basis so would not include the effect of the blended ethanol that is 

added downstream. A few notes on selected properties: 

The T50 minimum should be 150° F. T50 specifications for clear gasoline or subgrades is 170° F 

while the minimum specification for ethanol blended gasoline is 150° F, accounting for the 

boiling point depression experienced with ethanol blends. 

API and AFPM have included additional detailed comments on other properties based on more 

recent data and refining experience with gasoline blends, testing, and specifications. We support 

the comments offered by API and AFPM. 

Organization: POET, LLC
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POET also suggests that aromatics, benzene, and certain distillation temperature limits may 

warrant lowering from what EPA has proposed, to reflect a 15% ethanol content. For instance, 

EPA explains that ‘Additional ethanol blending to produce E15 is expected to result in even 

greater aromatics reductions.’ POET agrees that increased ethanol use, including via E15, can 

lower both total aromatics and benzene, and that lower certification fuel aromatics levels are 

appropriate. Both ethanol and aromatics are a source of octane, but ethanol provides a more costeffective and less toxic source of octane. 

Organization: Renewable Fuels Association (RFA)

Further, RFA suggests the EPA recognize the T50 temperature allowed for ethanol blended 

gasoline of 150°F in the ASTM International “Standard Specification for Gasoline for use in 

Spark Ignition engines.” RFA strongly recommends EPA align the certification fuels for nonroad engines as soon as possible with on road engine certification fuel. This ensures a uniform 

capability of spark ignition engines thereby streamlining the fuel options in the retail 

marketplace. 

Organization: National Automobile Dealers Association (NADA)

To enable Tier 3 tailpipe standard compliance, EPA should establish a 10 ppm gasoline sulfur 

average with a 25 ppm cap. To enable Tier 3 evaporative emissions compliance, a Reid Vapor 

Pressure (RVP) cap should be set at 9 psi for a maximum E10 gasohol test fuel. 

Our Response:

We are adjusting gasoline distillation temperatures to reflect in-use E10 gasoline to the 

extent practical. This includes adjustments to our proposed T10, T90 and FBP ranges based on 

review of updated Alliance of Automobile Manufacturer (AAM) fuel surveys and refinery batch 

data. Regarding T50, these data show a range of approximately 150°F to 220°F in in-use 

gasoline. Adopting a wide specification range for test fuel may have undesirable effects on 

consistency of results between facilities and over time. Therefore, we have chosen a range of 

190-210°F to represent both conventional and reformulated gasoline (as well as maintaining 

some overlap with CARB’s specification of 205-215°F). 

We are lowering the sulfur content of test fuel to 8-11 ppm to be consistent with the Tier 

3 in-use gasoline sulfur standards. Sulfur level has a significant effect on emissions so it is 

important to adjust the test fuel specification to match in-use fuel.

We are setting a benzene test fuel specification of 0.5-0.7 volume percent to represent inuse fuel under the MSAT2 regulations. The MSAT2 standards, which took effect January 1, 

2011, limit the gasoline pool to 0.62 volume percent benzene on average. 33 

We are lowering the range of aromatics content in the test fuel to better match today’s inuse E10 gasoline, and narrowing the range to limit variability of results. Data from recent 

gasoline batch data as well as AAM surveys support a specification of 22-26 volume percent. In 

 

33 72 FR 8434 (February 26, 2007).
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addition to total aromatics and benzene, the updated test fuel requirements place boundaries on 

the distribution of aromatics by carbon number (i.e., prescribed volume percent ranges for each 

of C7, C8, C9, and C10+ hydrocarbons). There is evidence that the heaviest aromatics in 

gasoline contribute disproportionately to PM emissions, so compliance with emission standards 

should be demonstrated on fuel with a composition representative of in-use gasoline. 

Some commenters raised concerns about specific ranges for distribution of aromatics 

resulting in use of pure compounds in test gasoline, which would not be representative of in-use 

fuels. On the contrary, historically, emissions test gasoline has often been found to have been 

produced using high proportions of single components (e.g., toluene, iso-octane), and therefore 

having additional targets for distribution of aromatics may actually increase the number of 

blending components required to meet the specification.

We are adjusting the olefins specification to a range of 4-10 volume percent to better 

match in-use E10 gasoline.

We are setting a range of 8-11 ppm sulfur in test fuel to mirror the expected in-use range 

after phase-in of the in-use sulfur standard of 10 ppm average. 

We are adding distillation residue, total content of oxygenates other than ethanol, copper 

corrosion, solvent-washed gum, and oxidation stability specifications to better control other 

performance properties of test fuel. These specifications are consistent with ASTM’s D4814 

gasoline specifications and CARB’s LEV III test fuel requirements.

We are updating some of the gasoline test methods previously specified in §86.113 with 

more appropriate, easier to use, or more precise test methods for ethanol-blended gasoline. Key 

changes include replacement of ASTM D323 with ASTM D5191 for measuring vapor pressure; 

replacement of ASTM D1319 with ASTM D5769 for measuring aromatics and benzene; and 

replacement of ASTM D1266 with three alternative ASTM test methods (D2622, D5453 or 

D7039) for measuring sulfur. The most current versions of these standards were specified where 

possible and appropriate. Additional response to comments on test methods can be found in 

Chapter 6.1.1.7 of this document.

Some commenters raised concerns about over-reliance on AAM fuel surveys, as well as 

lumping premium and regular grade fuel data together, when performing our analyses. We have 

generally performed parallel analyses using both refinery batch as well as AAM survey data 

where possible, and have focused on regular grade fuel where we believed that inclusion of 

premium would bias the results.

More information on data and analyses related to test fuel specifications can be found in 

Chapter 3 of the RIA.

4.5.1.5. Alternative Test Fuel Option / E30 

What Commenters Said:
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Organization: Advanced Biofuels USA (ABFUSA)

As part of the recently proposed Tier 3 motor vehicle fuel and emission regulations, EPA 

included a very forward looking idea that could bring higher octane, higher ethanol gasoline to 

the marketplace. 

However, Advanced Biofuels USA recommends the following changes to assure consumers get 

maximum fuel economy and climate change mitigation benefits from the EPA proposed higher 

octane, higher ethanol gasoline.

● Advance Biofuels USA fully supports EPA’s recognition of the importance of higher 

octane, higher ethanol (in the range of E30) gasoline as a cost-effective way to allow 

manufactures to maximize the efficiency of smaller, more efficient engines that utilize 

high combustion pressures to meet 2022 EPA CO2 vehicle emission standards. 

● To provide a smooth path to making this “higher octane, higher ethanol content gasoline” 

available nationwide EPA Tier 3 regulations should not require individual vehicle 

manufacturers to certify the availability of this fuel. Instead, EPA should use their 

authority under section 211 of the Clean Air Act to provide for the commercial 

availability of this “higher octane, higher ethanol content gasoline.” 

● In using the Clean Air Act authority to assure that “higher octane, higher ethanol content 

gasoline” is available nationwide EPA should implement a reasonable phase-in schedule 

tied to manufacturer production plans required to meet 2017 and later EPA GHG 

requirements. This schedule should be based on the “vehicles would not operate 

appropriately on other available fuels, and such a fuel would result in equivalent 

emissions performance,” information. 

● EPA should allow vehicle manufacturers that certify new vehicles with the “higher 

octane, higher ethanol content gasoline” to also certify that those vehicle are able to also 

operate on existing E10 or E15 fuels. These vehicles would be called “E30 capable.” 

● By building up the number of these “E30 capable” vehicles that could get the same 

mileage with a lower cost fuel, the demand for E30 would increase. This demand would 

create a nationwide E30 infrastructure that would then allow for the marketing of “E30 

Optimized” Vehicles designed to provide the fuel economy and GHG reductions 

necessary to meet 2022 CO2 reduction standards. 

● Since a higher proportion of lower cost ethanol is used to produce E30, the “higher 

octane, higher ethanol content gasoline” would probably not be priced above current 87 

octane E10 regular. Therefore, it should not be referred to as “premium” fuel in final 

regulations or for purposes of marketing but rather should be labeled differently. For 

example, “E30 capable/E30 optimized regular” fuel. 

● EPA should also provide flexibility in the Tier 3 regulations so that other renewable, 

negative GHG (as compared to petroleum) octane additives could be substituted for 30% 

ethanol when they are commercially available. In order to qualify, these additives should 

have to meet the applicable EPA regulations for fuel composition, aromatic content, and 

certification testing. This flexibility would promote competition in the biofuel 

marketplace that would result in the most sustainable low GHG solutions possible. 

By adopting a flexible, market-based Tier 3 higher octane, higher ethanol content gasoline 

program, EPA would send a clear Demand Certainty Signal to markets and fuel providers. This 
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clear signal will provide the currently missing certainty to the financial markets that will be 

needed to provide the capital for total-biomass ethanol and other advanced biofuel plants that 

will be needed to provide the “higher octane, higher ethanol content.” 

This clear market signal would be the most effective way to meet EPA’s stated goal to, “provide 

a market incentive to increase ethanol use beyond E10 and enhance the environmental 

performance of ethanol as a transportation fuel by using it to enable more fuel efficient engines.” 

EPA has the Authority under Section 211 of the Clean Air Act to Implement Nationwide 

Marketing of “Higher Octane, Higher Ethanol Content Gasoline”. 

As stated in this proposed rulemaking on pages 32-33, “We are proposing to adopt gasoline 

sulfur controls pursuant to our authority under section 211(c)(1) of the CAA. This section allows 

EPA to establish a fuel control if at least one of the following two criteria is met: (1) The 

emission products of the fuel cause or contribute to air pollution which may reasonably be 

anticipated to endanger public health or welfare; or (2) the emission products of the fuel will 

impair to a significant degree the performance of any emissions control device or system which 

is either in general use or which the Administrator finds has been developed to a point where in a 

reasonable time it will be in general use were the fuel control to be adopted.” Using the first 

criteria, the establishment of a higher fuel octane gasoline standard (fuel control) would reduce 

CO2 emissions from direct injection/turbocharged/high compression engines below what they 

would be with lower octane, lower ethanol content gasoline. This reduction in CO2 emissions, 

which have previously been determined by EPA to endanger public health and welfare as climate 

change inducing Greenhouse Gas (GHG) emissions, would come from two effects: 

1. These engines would run at higher efficiency with the higher octane fuel meaning less 

fuel/mile would be used resulting in less CO2 emissions/mile.

2. The increase from 10% to approximately 30% ethanol would decrease life-cycle 

GHG emissions when compared to the petroleum gasoline components it would 

replace. This decrease would become especially significant as proportion of total 

biomass (i.e. cellulosic) ethanol increases in accordance with the previously 

Congressional enacted Renewable Fuel Standard (RFS). 

It making this determination to require higher octane, higher ethanol content gasoline, it is also 

important to recognize that these interrelated engine design features (the Ford Ecoboost is an 

example) are being implemented for the sole purpose of meeting the 2022 EPA CO2/DOT mpg 

standards while also providing enough power to compensate for the extra weight requirements of 

DOT safety standards, and are not being introduced for high performance reasons. Therefore, 

engines using this integrated package of design features are as much emission control devices as 

the catalytic converters that caused EPA to issue lead elimination and sulfur reduction fuel 

control regulations to ensure lower HC, NOx, and CO emissions. 

Organization: Algenol Biofuels Inc.

Algenol appreciates EPA’s effort -- as it proposes to strengthen the Tier 3 Vehicle Emission and 

Fuel Standards-- to accomplish that objective in a way that maximizes the role which can be 
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played by biofuels blending. We believe EPA correctly seeks to implement the emissions 

reduction and biofuels blending programs in the most mutually reinforcing way. 

In particular, we wish to endorse and encourage the Agency’s proposal, in part IV.D. of the 

proposed Tier 3 rule, to allow vehicle manufacturers to specify an appropriate alternative test 

fuel, such as an E30 fuel, (a) for vehicles designed to be operated with higher octane, higher 

ethanol fuel,, optimized to run on an E30 or higher blend, (b) and/or for flex-fuel vehicles 

(FFVs). If properly constructed, this option will help to increase the demand for biofuels and 

facilitate their use by the driving public. We understand that Mercedes and other major auto 

manufacturers have expressed serious interest in this opportunity. 

Auto makers and the driving public could benefit from having such fuel available and used in 

designated vehicle models because it would enable the manufacturers to raise compression ratios 

and improve fuel efficiency in such vehicles as a step towards complying with 2017 and later 

greenhouse gas and CAFÉ fuel economy standards. The public would also benefit, economically 

and environmentally, from such an incentive for increased ethanol use, especially insofar as the 

ethanol involved is from a low-cost source such as Algenol. 

EPA proposes, in Part IV.D.1 of the proposed Tier 3 rule, to allow manufacturers to petition for 

use of such a mid-level blend in government-required emission certification tests for designated 

vehicles if the manufacturers demonstrate that (1) such fuel would be available nationwide, (2) 

such fuel would be used by operators of such vehicles, (3) the vehicles would not operate 

appropriately if other fuels were used, and (4) the fuel would result in equivalent (or better)

emissions performance to that attainable with other fuels. 

We believe that the first condition above is beyond what can realistically be expected for auto 

manufacturers to demonstrate. Instead, EPA needs to take regulatory action, under its existing 

statutory authorities, to mandate that the E30-type fuel be available in adequate quantities by a 

date certain. One precedent is EPA’s action in the 1970s to mandate the availability of unleaded 

gasoline to match the introduction of vehicle models with catalytic converters to prevent 

“poisoning” of those catalysts which greatly reduced automotive emissions below prior level. 

(The writer supervised that action while at the Agency.) 

We also urge that EPA give careful consideration to any reasonable requests that auto 

manufacturers may make regarding the 2d – 4

th Agency-proposed criteria listed above. The 3rd

and 4th criteria seem generally appropriate, depending on how they are actually interpreted and 

applied, but the second criterion – that drivers will use the fuel -- may need to be modified 

somewhat or at least applied with some flexibility. For example, this condition probably should 

not be construed to mean there is no conceivable way that some perverse drivers might not 

circumvent the intent of the program even though they would risk damaging the vehicle and 

possibly paying more for the inappropriate fuel they used. 

As a company that will be well along into commercial production of ethanol by the time an E30 

type option would go into effect, Algenol has a strong and legitimate interest in urging that the 

conditions for allowing use of E30 type fuels for vehicle testing be realistic to meet so that the 

statutory objective of expeditiously expanding use of ethanol can be meaningfully met. This 
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Algenol interest is consistent with the public interest which gave rise to the Congressional 

directive that EPA act to maximize biofuels use in vehicles insofar as this reasonably supports its 

other mandates such as minimizing vehicle emissions. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Recommendations concerning Optional Alternative Test Fuels. Vehicle manufacturers 

understand there could be a need for new test fuels in the future, such as higher octane, higher 

ethanol blends, depending on how market fuels develop and vehicle technology needs evolve. 

For example, there are potential benefits from such blends, assuming the octane grades of the 

underlying gasoline blend-stocks do not decline. Higher octane/higher ethanol content can 

improve vehicle efficiency and lower emissions. Automakers concur that EPA needs to replace 

the flawed existing regulations applicable to use of alternative test fuels [40 C.F.R. Sec. 

1065.701(c)], discussed further below. We look forward to working with the Agency and other 

stakeholders to develop better options for use of alternative test fuels. 

One pathway to improved vehicle efficiency and lower GHG emissions is to increase the engine 

compression ratio (CR). However, an increased compression ratio may result in the engine then 

requiring a fuel with a higher octane number (ON), a measure of the fuel’s resistance to autoignition that causes engine knock. Since ethanol has a higher ON than gasoline, a mid-level 

gasoline-ethanol blend (prepared by blending denatured ethanol into an E10) will have a higher 

octane number than the E10, allowing the engine to be designed with a higher CR. Ethanol’s 

high heat of vaporization, which produces an in-cylinder cooling effect, and its high octane 

number compared to that of gasoline, can increase engine efficiency. The resultant efficiency 

gains can also enable a downsizing of the engine to reduce weight, thereby further reducing fuel 

consumption and CO2 emissions. 

The Coordinating Research Council (CRC) conducted studies investigating the body of literature 

on the effects of fuel octane quality and ethanol on engine and vehicle fuel economy and 

emissions. Additionally, Ford conducted a study comparing the effects of E10, E20, and E30 on 

fuel economy and CO2 emissions from a turbocharged direct-injection engine. This engine was 

tested with CRs of 10:1 (current production) and 11.9:1. The selected E20 fuel operated in an 

engine with 11.9:1 CR gave similar knock performance to the E10 fuel operated in the same 

engine set to 10:1 CR. Similarly, the E30 fuel run at 11.9:1 CR resulted in knock performance 

equivalent to E20 at 10:1 CR. 

In a vehicle simulation study, the E20 at 11.9:1 CR provided a 5% reduction in CO2 emissions 

compared to the E10 at 10:1 CR, and the fuel economy (MPG) was about the same, even though 

the energy content of fuel was lower as the ethanol content was increased. To provide the desired 

high knock resistance, the higher-ethanol fuels should be formulated by using a blend-stock that 

retains the octane quality of the current blend-stock used for regular-grade E10.

While higher ethanol, higher octane fuels can be useful in all types of engines to varying degrees, 

they are of particular benefit to direct-injection (DI) engines. Ethanol has a much greater heat of 
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vaporization when compared to gasoline. Thus, in a port fuel injected (PFI) engine, the chemical 

octane rating increase can be realized, but since much of the fuel is inducted into the cylinder 

after it has vaporized, the cooling effect is not captured. In a DI engine, however, the fuel is 

introduced directly into the cylinder in liquid form and its vaporization in the cylinder results in a 

larger cooling effect compared to the PFI case, thereby reducing the octane number requirement 

of the engine. However, advanced design for either type of engine can benefit from higher octane 

fuels. 

EPA Should Replace Flawed Regulations Governing Use of Alternative Test Fuels. Automakers 

agree that alternative test fuel provisions in the current regulations at 40 C.F.R. §1065.701(c) are 

flawed and cannot work in practice. For dedicated vehicles, the regulation requires that the new 

fuels are commercially available in the marketplace, and it appears to presume the fuels would be 

widely available without any vehicles being available to use them, which underscores the 

unresolved “chicken and egg” dilemma. 

In addition, automakers would have to show that the vehicles will not run or be durable on 

standard test fuel. Alternatively, automakers could show that the vehicles would not meet 

emissions limits on standard test fuel, any of which would likely make them virtually unsellable. 

Finally, Sec. 701(c) does not address F Factors that would have to be determined for these 

alternative fuel types. Rather than imposing unrealistic regulatory pre-conditions, EPA needs to 

replace them. Were an OEM (Original Equipment Manufacturer) to petition to test using E15 test 

fuel under these provisions, meeting the criteria would be very challenging. Automakers would 

be happy to work with the Agency to develop a workable process and criteria for access to 

alternative test fuels. 

Approval of a fuel for certification test purposes does not change the CAA requirements that a 

new fuel be independently approved by EPA as substantially similar (or a waiver provided) with 

full notice and comment rulemaking before use as market fuel (other than for FFV use for up to 

E85). Likewise, mechanisms to avoid mis-fueling in vehicles or equipment not designed for a 

particular fuel use would also have to be addressed. 

EPA’s Approach to Use of Premium Octane Grade Test Fuel is Sound:

Automakers support consistent reliance on communications in the Vehicle Owner Manual 

regarding vehicle care and fueling recommendations, and terms of warranty protection. Owner 

Manuals requiring (as opposed to recommending) use of Premium Octane Grade fuel are the best 

means to determine which vehicles should be allowed to test on it. Also, EPA’s approach 

provides critical consistency with California’s requirements.

EPA is seeking comment on the need for limiting the maximum octane of gasoline used in the 

certification of premium-required engines and vehicles. Automakers agree that there is no need 

to limit the maximum octane of gasoline used in the certification of premium-required engines 

and vehicles. Doing so would be an obstacle to the development of highly efficient optimized 

vehicles.
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EPA should finalize its provision for testing on premium grade octane fuel as written. 

Organization: Clean Fuels Development Coalition (CFDC)

That notwithstanding, we respectfully draw your attention to several key points that warrant 

repeating. First is the issue of an E30 certification fuel and providing this option to automakers. 

Many have indicated their support for high octane fuels and recognize ethanol’s outstanding 

octane properties. For those automakers that choose to do so allowing them a pathway to E30 

certification is another key step in expanding ethanol markets. For those who find this an 

attractive option, a poison pill can easily be viewed as the requirement that automakers must 

demonstrate the commercial availability of such fuel. We believe that is unnecessary and quite 

impractical. The successful CAFÉ credits afforded to automakers for example in the production 

of flex-fuel vehicles, was achieved completely independent of fuel supplies and automakers 

responded to market developments and regulatory signals by making more FFVs available. We 

believe this would certainly be the case with E30 capable or optimized vehicles and if not 

corrected in this Rule would be a huge impediment to them. Similarly, infrastructure would 

follow as more of these vehicles were on the road. 

Organization: American Coalition for Ethanol (ACE)

Alternative Certification Fuel (such as high-octane E30):

To the contrary, EPA suggests auto manufacturers can chose to certify on higher ethanol blends 

only if they ‘could demonstrate that such a fuel would be used by the operator and would be 

readily available nationwide.’ ACE believes such a requirement gives control of fueling 

decisions to the oil industry, which has historically only allowed new blends of ethanol when 

they have been required to do so by law. Oil company contracts banned E10 when it came to the 

marketplace, effectively restricted E85 to only a small percentage of stations, and currently 

prevent branded stations from marketing E15. The oil industry would likely continue to limit 

E15 and place an outright ban on E30 if it believed it could keep car manufacturers from 

building cars that can run on those fuels that compete with their petroleum fuels. 

ACE appreciates that EPA proposes to allow automakers who wish to increase compression 

ratios and make other advanced technology improvements to engines in order to comply with the 

2017 and later GHG/CAFE standards, to specify an alternative high-octane test fuel such as E30. 

As such, we strongly recommend that EPA establish an E30 (or comparable midlevel blend of 

ethanol and gasoline) certification fuel for model year 2017 and beyond, with incentives offered 

to encourage automakers to make that conversion earlier. As mentioned earlier, ACE strongly 

objects to EPA’s suggestion that approval of such a certification fuel is contingent upon 

automakers’ demonstrating commercialization of the fuel. 

That suggested requirement is undoubtedly based on E85 history and the lack of E85 fueling 

stations. ACE believes that to be an inaccurate comparison. Automakers did not build E85 

vehicles. They built Flex-Fuel Vehicles. As such, since FFVs could also use unleaded gas or 

E10, station owners already had fueling infrastructure to provide fuel for FFVs. Buying new 

tanks, lines, and dispensers to offer fuel to vehicles a station could already serve only made sense 

at times of large price advantage, and later, when marketers learned how to use E85 and blender 
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pumps to recover some of the ethanol blending margin that refiners were taking through preblended E10. Had automakers built E85 vehicles, station owners would have had to decide 

whether to concede that market to competitors or offer E85 for a competitive edge. 

In an effort to set aside the infrastructure discussion, while ACE prefers a higher octane fuel with 

a minimum ethanol content requirement such as E30 for use as a certification fuel, as an 

alternative, we feel so strongly about ethanol’s octane value that we could support a transitional 

certification fuel that specifies only the octane of the fuel. Existing fuel infrastructure could be 

used to sell a 95 octane consumer fuel product, for example, so the burden of infrastructure 

development would not fall on ethanol. We believe other properties of ethanol will make octane 

from ethanol more attractive to automakers, and ACE believes in a truly competitive 

marketplace, ethanol’s low-cost will present profit opportunities for station owners that far 

outweigh costs to upgrade, while still allowing late adapting fuel stations an option for fueling 

new vehicles with high octane gasoline. 

In either case, it is imperative that automakers let fuel station owners and consumers know well 

in advance what kind of fuel — either by octane or by ethanol content, or both - they plan to use 

in the future, so that both have time to adjust for that fuel. 

A recent New York Times article1reports that an alternative certification fuel such as E30 enjoys 

widespread support from technical automotive experts. Mr. William H. Woebkenberg, senior 

engineer for fuels policy in the U.S. at Mercedes-Benz, says in that article than an E30 blend in 

an engine designed to use it would be attractive to consumers with ‘ridiculous power and good 

fuel economy,’ and that those car owners would seek out the fuel. 

As EPA balances the administration of Tier 3, CAFE-GHG, and the RFS; adoption of higher 

octane blends such as E30 will be critical to achieving the desired impact of each policy. As 

such, EPA should more directly facilitate higher octane blends like E30 by independently 

approving a cert fuel for these types of higher octane blends. 

Organization: California Air Resources Board (CARB)

CARB staff also supports the proposed requirements for midlevel ethanol blends, as well as 

promoting the power plant design advantages of an E30 blend. 

Organization: Chevron Products Company

Per the request for comment on the appropriateness of the alternative test fuel provisions at 

§1065.701(c), the regulatory language already in place appears to be adequate given that it: 1) 

requires EPA approval for the specifics of the test fuel; and 2) requires that there be evidence of 

commercial availability. The existing language presents no barriers to the certification of a 

higher octane, higher ethanol content test fuel and there is no need to more precisely specify the 

makeup of potential alternative fuels. The current language allows for innovation in vehicle and 

fuel technology. A more prescriptive approach which dictates the nature of such fuels would 

only create barriers to such innovation. It should be noted that the example of a higher octane, 
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higher ethanol fuel to be used in dedicated vehicles is in fact an alternative fuel rather than 

gasoline and should be treated as such. 

Organization: American Council on Renewable Energy (ACORE)

Furthermore, I believe there are several additional critical points that should be considered before

EPA finalizes Tier 3 regulations, and propose actions that should be taken as soon as possible. I 

make these proposals based on my experience as the Director of the Office Regional Operations 

at the Federal Energy Administration (FEA). There I learned the hard way that oil companies, 

during our national transportation fuels crises in the mid-1970s, illegally took action to gain 

corporate power and position at the expense of the American people. The FEA took many of the 

oil companies to court and won fines large enough to fund the energy offices in all 50 states for 

about two decades. During this critical period of fuel shortage, they were still able to boost 

profits, eliminate the lower levels of their competition (some independent fuel suppliers and most 

of the “mom and pops” that were involved in their own communities) to further concentrate their 

dominance of the transportation fuels market. 

From then on, I made a personal commitment to find an alternative to oil as the primary source 

of transportation fuels. With the help of EPA Administrator Russell Train and C. Boyden Gray, 

Council to Vice President Bush, I was able to help pioneer the ethanol industry starting in 1975 

and the biodiesel industry in 1980. 

It is critically important that the United States Congress and the Administration take into full 

consideration critical factors impacting America’s biofuels program. Congress should not be 

swayed by the powerful and widespread exaggerations berating ethanol orchestrated by the oil 

industry and their colleagues, who seek lower corn prices. The animal feeders and those formerly 

enjoying the benefits of subsidized corn through lower meat prices, at the taxpayers’ expense, 

want a return to the earlier lower corn prices that were below free market costs. This would lead 

to the U.S. being forced to return to price subsidies that would disrupt free market forces to the 

disadvantage of corn farmers worldwide; and, at the expense of the U.S. taxpayers. 

The ethanol industry has eliminated the need for corn subsidies in the U.S., resulting in free 

market prices worldwide for both corn and ethanol. This was due to the major contributions by 

the ethanol industry and the wisdom of the Congress and the Administration to terminate the 

VETEC that was subsidizing ethanol.

Additionally, this rhetoric, focused on discounting critical factors such as resource availability, 

technological and scientific advances, the U.S commitment to keep the world’s oil lanes open for 

commerce, true climate change factors, and the value of additional externalities, swayed the 

political process so that these factors are no longer principal determinants in establishing market 

share for various transportation fuels. These conditions have been overpowered by political clout 

influenced by misinformation and there are two very recent examples of this. The first is when 

Harley Davidson motorcycle riders circling the Capitol building and visiting congressional 

offices to persuade votes against E-15. EPA regulations do not allow the use of this fuel in

motorcycles, and motorcycles have easy access to ethanol free gasoline. The second entails 

restaurant associations demonstrating on the Hill and in the media against the RFS claiming that 
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corn-based ethanol leads to an increase in meat and dairy prices. It is well established that oil 

costs have a greater impact on these prices than the cost of corn, and the availability of distillers 

grains replacing a good percentage of the feed for animals is further offsetting in reducing the 

cost of meat. Then there is the issue that meat, particularly fatty meats, is losing popularity; 

already leading to less corn in some animal diets. These factors and other mentioned externalities 

including sustainability, climate change, short and long range economics, and job creation -- not 

misleading rhetoric must be used in the making process. One can assume the connection to the 

bikers and the restaurateurs to the oil industry are not hypothetical. 

The oil industry was using similar spin tactics almost a century ago to promote dangerous lead in 

gasoline to attain needed octane for advanced engines. They defeated cleaner-burning ethanol 

preferred by many, including Henry Ford. They were able to knowingly allow the introduction of 

lead into the blood of millions of Americans for almost a half century at enormous expense to 

human health, including very significant reductions in the IQs of kids living in traffic-congested 

cities until it was phased out and replaced by methyl tertiary butyl ether (MTBE). This chemical 

is a known ground water contaminant; again, large oil conglomerates restrained the use of 113 

octane ethanol while advancing that contaminant. When MTBE was phased out because of 

ground water contamination and other health problems, their preference shifted to aromatics for 

most of their octane, leaving it up to free market forces, the marketplace and legislation (the 

Renewable Fuel Standard—RFS) to incorporate ethanol into gasoline at the 10% level. The oil 

industry, the public, and the environment benefited from the RFS because of its lower financial 

cost as an octane enhancer and the other previously mentioned externalities. However, oil began 

to lose market share. About that time, EPA was considering authorization of the additional use of 

ethanol (E-15), and it was becoming apparent that the auto industry was looking into 93+ octane 

fuels to permit the transition to direct injected, high compression/turbo charged engines. The oil 

industry knew this combination could open the way for higher blends of ethanol and increasing 

numbers of flex-fuel vehicles (FFV) on the road, serviced by blender pumps. The market share 

for gasoline was being seriously threatened – totally unacceptable to the oil industry. 

They turned to their proven power base: money, political clout, and disinformation. Their 

decade-long campaign has been overwhelmingly successful throughout society, especially in the 

Congress that is well attuned to: public opinion and their support; successes of U.S. oil and gas 

production; reduced oil import dependence; and, of course, endless anti-ethanol rhetoric. This all 

leads to good news for fossil fuels and bad news for ethanol. 

Also, allow me to share with you my reaction to the President’s speech on climate change. 

Thankfully, he mentioned a commitment to biofuels, but without proposed action except for 

support for the Renewable Fuels Standard and biofuels in general. I believe he has a stronger 

commitment to ethanol, but was restrained by the threatening climate orchestrated by the oil 

industry and their compatriots. That is the key reason for my concern. The President of the 

United States, his key staff members, Congress, and the public have, for quite some time, been 

pressured by the oil industry and their colleagues influenced by the involved animal feeding 

industries. This powerful force has set the stage for their victory. Non corn-based biofuels in 

general still has good support. The corn-based ethanol industry had a strong support base while 

pulling the industry to today’s point of providing 10% of the gasoline mix while contributing 

billions of dollars annually to the nation’s economy. In recent years, however, it has essentially 
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lost most of its support across the board in a variety of ways. This is all good news for the fossil 

transportation fuels, and bad news for biofuels, particularly the pioneering corn-based ethanol. I 

believe President Obama would like to fix this inequity; but political and public conditions signal 

otherwise. However, EPA has the authority and the reasons to come to the support of the

President, the nation and the environment. 

Without EPA action, all of this signals a possible demise of the ethanol industry unless EPA 

embraces it’s legally imposed responsibilities, the compelling signals from the marketplace, and 

its mandate to protect the environment (including the consequences of climate change and public 

health). Comments by the Coalition/Urban Air Initiative (EFC/UAI) provide all the evidence 

needed for EPA to immediately move to correct “oversights” and delays in their actions over the 

past 35 years, since the forced phase-down of lead in gasoline. The agency should not be delayed 

further by current political and public opinion, nor mislead by a massive and prolonged antiethanol campaign. 

To further reinforce the EFC/UAI comments and my recommendation, attached is a copy of my 

article published in the Physicians for Social Responsibility: Environmental Health Policy 

Institute that reinforces my comments on the unacceptable negative health effects of excessive 

aromatics in gasoline. It also touches on the positive environmental benefits of corn and it 

conversion in a biofuels. 

EPA must carry out their responsibilities and opportunities under the law to protect public health, 

the environment, and the best interest of the nation. It should fully support the President’s 

commitment to biofuels and the essential need to reduce carbon emissions, and not continue to 

bow to the powerful influence of those committed to the continuation of oil’s dominance in the 

transportation sector. 

In summary, here are the benefits to the nation, using existing authorities, to reduce aromatic 

levels in gasoline, boost levels of renewable alcohols, incentivize the production of FFV, and 

encourage funding support at the state and federal levels for the inclusion of blender pumps at 

refueling stations: 

Reduce oil dependency 

Reduce gasoline prices 

Give drivers cleaner fuel options 

Reduce carbon emissions (Heavy carbon emissions in gasoline are 40% greater than diesel fuel 

due to the heavy carbon nature of ultra fine particulates (UFP)). This is in addition to the reduced 

carbon footprint of ethanol production and use, both of which are steadily improving. This is not 

the case with oil based gasoline that is not sustainable and whose carbon footprint will only rise 

as oil gets harder to obtain while getting heavier and dirtier 

Reduce health-related costs by tens of billions of dollars annually as verified by studies at 

Harvard and elsewhere and also highlighted in the EFC/UAI comments and my enclosed article.
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Permit the auto industries to transition up to 93 octane gasoline as a standard fuel thereby 

optimizing engine performance through direct injected and higher compression/turbocharged 

engines. (Many high-powered new cars use 93 octane fuels) 

Permit the attainment of CAFÉ standards by 2025 – 54.5 MPG 

Reduce greenhouse gas emissions and put America on the path to sustainability 

Provide drivers choices based on costs and desires in terms of sustainability and carbon 

footprints 

Catch up with Brazil in terms of the availability of FFV and fuel choices. See the chart on FFV 

growth in Brazil. 

Maintain the U.S. as a world leader in biofuels. If we are governed by the preferred policies of 

big oil, we could fall behind rapidly as indicated by the following: 

In France, Amyris and Total announced a successful demonstration flight at the Paris Air Show 

of its renewable jet fuel made from Amyris Biofene, and ultimately, from plant sugars. The 

Airbus A321 aircraft powered by two Snecma CFM56 jet engines flew from Toulouse to Paris 

with a blend of renewable jet fuel produced by Amyris and Total. This demonstration flight was 

in support of the French Initiative for Future Aviation Fuels, which seeks to produce and 

commercialize alternative, renewable, and sustainable aviation fuels in France in the coming 

years. 

We are now at a critical junction internationally and domestically in terms of the future of 

transportation fuels in the United States. EPA has the legal authority to take the positive actions 

outlined above. Doing so would ensure a bright future for the nation in respect to biofuels. If the 

EPA allows itself to be driven by the financial and political clout of non-renewable 

transportation fuel, biofuels will likely be seriously weakened in the U.S. This is an advantage 

the oil industry, Brazil, Europe, and other regions including China will gain. The EPA’s failure 

to adequately support FFVs and reductions in the authorized level of aromatics in gasoline has 

already placed us on the downhill slide. 

It is not to too late for the EPA to take the steps they are authorized to implement, and are 

morally compelled to do so. While updating of their pertinent models and the imputing of good 

and sensible data will fully justify the recommendations cited above, timing is critical. There is 

already fully enough data compelling EPA to act now, and they must do so in the best interest of 

the United States and world’s population, as well as the environment. 

America has made great strides in reducing emissions and improving the efficiency of our 

transportation system and technologies. But simply utilizing less petroleum, while essentially 

relying on it as the single transportation fuel source is not sufficient to meet the energy, 

economic and environmental security we need. What would happen if the Iranians decided to 

close down the Strait of Hormuz? Despite expanded oil production in our country, the price of 

oil, determined on the global market, would immediately jump to $150-200 per barrel, severely 
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impacting our economy. There are also many plausible terrorist and natural disaster scenarios 

that would produce a similar impact. 

Every barrel, every percentage of oil that we can displace as America’s primary fuel for 

transportation with clean, domestic biofuels mitigates against the potential negative impact of an 

oil price spike on our government, military, overall economy and individual consumers. 

Therefore, efforts to improve vehicle emissions and reduce sulfur content must include the 

utilization of greater amounts of clean, domestic biofuel. 

Higher amounts of biofuel in our gasoline have significant economic benefits. In 2011, an 

ethanol blend of 10% reduced gasoline prices by $1.09. At the same time, over 200 ethanol 

plants and refineries supported economic growth across America’s heartland. As a whole, the 

ethanol industry employs over 400,000 Americans across the country, especially in rural regions 

of the country, and is doing so during a time where many Americans need steady employment 

and good jobs. 

The economic benefits of incorporating higher amounts of ethanol into our gasoline are 

significant, but so are the positive environmental impacts at the local, regional and global level. 

Higher octane/ higher ethanol content gasoline will reduce the harmful air emissions that lead to 

an estimated 50,000 premature deaths a year. Ethanol is the cleanest and most affordable source 

of octane on the market today, displacing toxic aromatics such as benzene and toluene. In 

addition, ethanol reduces greenhouse gas emissions by 40-50% when compared directly to 

gasoline. 

Organization: A 2nd Opinion Inc.

As an informed consumer I am very concerned about the use of gasoline containing up to 15% 

ethanol (E15). My owner’s manuals approve the use of gasoline containing up to 10 percent 

ethanol (E10) and imply that if I use other fuels my warranties are not valid. I know the 

Environmental Protection Agency (EPA) thinks E15 will not harm cars produced since 2001. I 

also know that the Coordinating Research Council (CRC) has tested cars and fuel system 

components and concluded that millions of cars could have fuel system failures if they use E15. 

No one will know whether the EPA or the CRC is right for several years. But as a senior citizen 

consumer, I do not want to take the risk. Therefore I am proposing as a compromise, that you ask 

the Renewable Fuels Association (RFA) to administer a Federal Auto Repair Trust. Here is an 

outline of how it would work: 

Each ethanol producer/importer would volunteer to deposit one cent for every gallon of fuel

grade ethanol produced in or imported into the United States in the trust which RFA should 

volunteer to administer. 

Owners of gasoline powered vehicles that are not certified as flex fuel (E85) that experience fuel 

system failures after using E15 can recover their out of pocket repair costs from the trust. The 

trustee may use trust funds equal to %5 of the disbursed repair costs to cover administration 

costs. 
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Effective with the 2014 model year, all gasoline powered vehicles sold to U.S. consumers must 

be certified to perform on high ethanol content gasoline. 

Ten years after all gasoline powered new cars sold in the United States are required to be 

compatible with E15 or five years after the last claim was paid whichever is later, the RFA 

would be required to disburse the unused FART to the ethanol producers/importers who made 

the FART deposits. If EPA is right, the depositors get all their FART deposits back. If CRC is 

right each depositor would get a pro rata share of the residual FART. (Individual FART 

deposit*(Total FART deposits minus 105%FART costs)/Total FART deposits)) 

I selected the acronym to get your attention and to have a little fun. I hope it did brighten your 

day. But, I am serious about wanting environmental justice concerning these repair costs. The 

people should not pay for repairs to fuel system damage caused by the ethanol industry. Nor 

should the refining industry. The industry that profits from E15 should provide environmental 

justice and 0.15 cent’s per gallon gasoline is cheap. 

EPA should encourage RFA to jump on this opportunity as a good compromise. 

Organization: American Lung Association

EPA outlines a process whereby a manufacturer could design vehicles to operate on higher 

octane and higher ethanol content gasoline, i.e. E30 or higher. We support the approach that 

allows for a petition for certification on such fuels if demonstrated that such fuels will be readily 

available nationwide, will be used by the vehicle operators, vehicles would not operate 

appropriately on other available fuels, and such a fuel would result in equivalent emission 

performance. All confirmatory testing should be conducted on fuel that matches the certification 

fuel. 

Organization: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

EPA states that its goal is to reduce the number of certification fuels that manufacturers would 

need to use to test their vehicle fleet, and yet the Agency proposes to allow vehicle 

manufacturers to request approval for alternative certification fuels such as those which contain 

high ethanol content. EPA should not finalize rules allowing vehicle manufacturers to certify on 

various alternative blends, as it could have a significant impact on market dynamics, such as a 

proliferation of boutique fuels that do not fit with the existing fungible fuel system or service 

stations storage tank configurations. 

Proliferation of Test Fuels: Part of EPA’s goal in modifying the certification fuel for Tier 3 was 

to reduce the number of certification fuels manufacturers would need to use to test their vehicle 

fleet. This goal seems to be lost as EPA is proposing to “allow vehicle manufacturers to request 

approval for an alternative certification fuel such as a high-octane 30 percent ethanol by volume 

(E30) blend for vehicles they might design or optimize for use on such a fuel. This could help 

manufacturers that wish to raise compression ratios to improve vehicle efficiency, as a step 

toward complying with the 2017 and later light-duty greenhouse gas and CAFE standards (2017 
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LD GHG). This in turn could help provide a market incentive to increase ethanol use beyond 

E10 by overcoming the disincentive of lower fuel economy associated with increasing ethanol 

concentrations in fuel, and enhance the environmental performance of ethanol as a transportation 

fuel by using it to enable more fuel efficient engines.” Allowing each manufacturer the option to 

request approval of an alternative certification fuel could have significant impact on market 

dynamics. One can imagine a proliferation of boutique fuels necessary to support each individual 

manufacturer so that their vehicles can actually deliver the fuel efficiency as tested. This 

approach does not fit with the extensive, fungible fuel system that currently exists nor does it 

account for the limited fuel options available at service stations due to underground storage tank 

configuration and space availability. How does EPA expect to steward such a program and who 

would be responsible for determining the cost, well-to-wheel emissions, etc? One could image an 

engine that is optimized on an alternative certification fuel but would not deliver anywhere near 

the efficiency on in-use fuels so regarding alternative fuel availability, what would be the market 

threshold for EPA to consider allowing a manufacturer to use an alternative certification fuel? 

Organization: E.I. du Pont de Nemours and Company

The second provision that could encourage larger volumes of renewable fuels involves allowing 

vehicle manufacturers to request approval for an alternative certification fuel such as high-octane 

E-30. This provision would give vehicle manufacturers the requisite flexibility to improve 

vehicle efficiency for purposes of complying with 2017 and later CAFÉ standards. DuPont 

supports allowing vehicle manufacturers to request alternative certification fuels. This policy 

could promote higher octane fuels coming to market with lower cost as compared to their high 

octane petroleum fuel counterparts. High octane petroleum fuels are more expensive than 

gasoline with an 87 rating, but higher biofuel blends with higher octanes should cost less per 

gallon of regular gasoline. 

The Tier 3 rule objectives go hand in hand with CAFÉ standards and would create the flexibility 

that automobile manufacturers need to comply with both CAFÉ and the Tier 3 rule. The purpose 

of CAFÉ standards is to reduce energy consumption that will help address our country’s 

dependence on imported oil, save consumers money at the pump, and reduce emissions of 

greenhouse gases that contribute to global climate change. Higher ethanol blends will help make 

significant contributions to these objectives. 

Opponents of the Tier 3 rule have argued that “proposed fuel specifications should be based on 

sound science in order to accommodate vehicle technologies that automakers will commercialize 

in significant volumes within the same timeframe required of fuel providers.” They fault EPA for 

not identifying “automotive technologies that would be utilized to comply with increased CAFÉ 

standards or a Tier 3 standard that would benefit from lower sulfur gasoline.”

These arguments seek to solidify the current obstacles that prevent both higher blends of biofuels 

and advanced vehicle technologies. Without the availability of higher ethanol blends on the 

market, automobile manufacturers are hesitant to develop engines that can accept the fuel. 

Likewise, without advanced engines, market demand for advanced fuels is lacking. DuPont 

believes that the Tier 3 rule is an opportunity to make progress towards overcoming these 

obstacles.
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The second provision that could encourage larger volumes of renewable fuel involves allowing 

vehicle manufacturers to request approval for alternative certification fuel, such as E-30. And 

that would give vehicle manufacturers the requisite flexibility to improve vehicle efficiency for 

purpose of complying with the 2017 rules.

We support allowing vehicle manufacturers to request approval for alternative certification fuels, 

higher octane fuels, because ethanol cannot be used as an octane booster. High octane petroleum 

fuels are more expensive than gasoline with an 87 rating. But higher ethanol blends with higher 

octane should cost less per gallon than regular gasoline.

Organization: Biotechnology Industry Organization (BIO)

Biofuels and Their Supportive Policies Are Important to the U.S. Fuel Supply; The federal RFS, 

enacted in 2005 and updated in 2007, is an important tool in achieving the objectives of energy 

independence and pollution reduction. The RFS is the single most important federal policy 

driving investment and commercialization of conventional and advanced biofuels. Biofuel 

production under the RFS has already displaced nearly 10 percent of gasoline consumption and 

will account for more than 20 percent of U.S. transportation fuel by 2022. Biofuel production 

under the RFS reduced the need for imported oil by more than 462 million barrels in 2012. 

Investment in biofuels, largely spurred by the RFS, has led to the development of facilities like 

INEOS Bio’s in Vero Beach, Florida, and KiOR’s in Columbus, Mississippi, which represent 

several hundred million dollars of investment in the United States and are poised to begin 

production of the next generation of renewable fuel from non-food feedstocks this year. Dozens 

more advanced biofuel projects are planned or under construction, as highlighted in the attached 

Appendix I, illustrating the visible success the RFS has had in driving development of highly 

skilled, well-paying jobs in rural America. Biofuel production under the RFS has led to the 

employment of 380,000 Americans. And, 800,000 employment opportunities could be created by 

2022. 

BIO firmly believes that the limits to market access for biofuels commonly referred to 

collectively as the “blend wall” represent a series of barriers contrived by obligated parties to 

prevent biofuels from gaining access to the marketplace. Multiple avenues exist for blending 

additional volumes of biofuel into the nation’s fuel supply. For instance, as the proposed rule 

recognizes, E15 blends are approved and ready for use, and production of flex fuel vehicles 

continues to increase. These options, combined with the introduction of new “drop-in” fuel 

molecules, provide a suite of opportunities for the growth of the entire biofuels industry and RFS 

compliance. 

The main obstacle to this growth and compliance is the dilatory tactics of obligated parties to 

pursue the options available to them. Obligated parties have had over five years to begin 

establishing the infrastructure necessary to distribute RFS-mandated biofuel volumes, but have 

taken few steps to do so. EPA should therefore resist all efforts by obligated parties to postpone 

updating the U.S. certification fuel for emissions from light duty cars and trucks and heavy duty 

gasoline vehicles, or to reduce RFS obligations based on blend wall claims. Any concession by 
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EPA to accommodate these assertions regarding the blend wall will only serve to embolden 

obligated parties in their effort to resist compliance with the Clean Air Act. 

Instead, as it is able through the proposed rule and other administrative actions, the Agency 

should encourage the development of biofuels – and the engines and infrastructure to support 

them. This development can readily grow the supply of biofuels in the market and overcome the 

blend wall by allowing Renewable Identification Numbers (RINs) to truly reflect their market 

value. It will also help drive the market and encourage retailers to adopt new infrastructure as 

reflected in Appendix I. 

EPA should also seek to identify opportunities to grow biofuel markets, including for drop-in 

biofuels. Reconsideration of the gasoline base fuel would enable engine manufacturers to 

optimize beneficial characteristics of biofuels in engine design, while expedited approval of new 

molecules would provide obligated parties with additional options for compliance not subject to 

blending limitations.

BIO believes the final Tier 3 rule has the potential to continue the progress of the biofuels 

industry and help alleviate the “blend wall” as described above. BIO commends EPA’s efforts to 

transition the certification test fuel for emissions from light duty cars and trucks and heavy duty 

gasoline vehicles (“the emissions test fuel”) to better reflect the current and future in-use fuel as 

it begins to contain greater volumes of biofuels resulting from the continued development and 

commercialization of biofuels and increased RFS volumes in the market. 

BIO believes that EPA should work to finalize its Tier 3 rulemaking and set the emissions test 

fuel to encourage further investment and adoption of biofuels, including advanced drop-in 

biofuels, ethanol and other fuel molecules. Encouraging biofuels, including higher blends of 

ethanol and drop-in biofuels would help meet EPA’s overall goal in this rulemaking to address 

the impacts of motor vehicles and fuels on air quality and public health. For instance, advanced 

drop-in biofuels have the same molecular make-up of traditional petroleum-based fuels, but they 

contain little or no sulfur and have significantly reduced GHGs. In addition, ethanol combusts 

without producing air toxics, which are the main source of particulate matter. Blending ethanol 

in gasoline also reduces the need for unhealthy detergent additives which are mandated to reduce 

the formation of engine deposits from gasoline that increase exhaust emissions and result in the 

loss of fuel economy and performance. These benefits of biofuels only rise with higher blends. 

BIO encourages EPA to issue a final rule that maximizes investment and adoption of all biofuels, 

including higher blends and drop-ins. 

EPA requests comment on various ways to transition the emissions test fuel, including: starting 

with a transition to E10 with a transition to E15 as that fuel becomes more widely available on 

the market; transitioning to E15 after a few years to allow time for this greater market 

availability or by setting a date certain by which the transition should be made to help drive E15 

market availability; or, allowing “vehicle manufacturers to request approval for an alternative 

certification fuel, such as a high-octane 30 percent ethanol by volume (E30) for vehicles they 

might design or optimize to use such a fuel” so that it may “help manufacturers that wish to raise 

compression ratios to improve vehicle efficiency, as a step towards complying with the 2017 and 

later light-duty greenhouse gas and CAFE standards.” 
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As BIO describes above, we urge EPA to issue a final Tier 3 rule that maximizes investment and 

adoption of biofuels. We agree with EPA’s assertion that E10 is widely available and in use in 

today’s market, and that E15 and E85 are the most likely near term biofuels that have the 

potential to be widely available. We believe the final rule should allow for and encourage 

ongoing and greater use of E85 and E15, as well as the transition to higher blends of ethanol, and 

drop-in biofuels. 

To this end, BIO urges EPA to issue a final rule that recognizes that new biofuel molecules are 

beginning to enter the market for blending with gasoline in order to help achieve the goals of the 

RFS. As such, we urge EPA to ensure that any transition in the certification fuel not create 

unintended barriers and burdensome costs to companies working to register these new biofuel 

molecules under Part 79 fuel and fuel additive registration. 

As EPA suggests, one way to accomplish this goal may be to allow vehicle manufacturers to 

request approval for an alternative certification fuel such as a high-octane E30 blend for vehicles 

they might design or optimize for use on such a fuel. BIO is aligned with EPA’s assertion in the 

proposed rule that “[t]his could help manufacturers that wish to raise compression ratios to 

improve vehicle efficiency, as a step toward complying with the 2017 and later light-duty 

greenhouse gas and CAFE standards...[t]his in turn could help provide market incentive to 

increase ethanol use beyond E10 by overcoming the disincentive of lower fuel economy 

associated with increasing ethanol concentrations in fuel, and enhance the environmental 

performance of ethanol as a transportation fuel by using it to enable more fuel efficient engines.” 

Preliminary results from Oak Ridge National Laboratory and the University of Wisconsin 

suggest that moderate biofuel blends increase the benefits of the use of Reactivity Controlled 

Compression Ignition (15). Therefore in order to further help manufacturers develop engines 

which can utilize biofuels which deliver reductions in greenhouse gas emissions; BIO 

recommends EPA sets the “R-factor,” which may be considered as the efficiency with which the 

vehicle engine adapts to fuel variations, at a value of 1.0. By doing so, EPA will ensure the final 

rule does not discourage manufacturers from developing engines that can utilize new cleaner 

burning biofuels in order to achieve the overall goals of the proposed rule. 

BIO believes the final Tier 3 rule has the potential to compliment other transportation related 

policies, including the RFS, which promote the continued development, commercialization and 

use of biofuels. We commend EPA’s efforts to transition the emissions test fuel to help promote 

the goals of the RFS. BIO believes that EPA should work to set the emissions test fuel to 

maximize investment and adoption of all biofuels, including higher ethanol blends and drop-ins, 

while also maximizing the level of octane in the U.S. fuel supply. This action would help EPA 

meet one of its stated goals of this rulemaking to address the impacts of motor vehicles and fuels 

on air quality and public health. 

To this end, we believe the final rule should allow for and encourage ongoing and greater use of 

E85 and E15, as well as the transition to higher blends of ethanol and drop-in biofuels. 

BIO also supports EPA’s proposal to allow vehicle manufacturers to request approval for an 

alternative certification fuel such as a high-octane E30 blend for vehicles they might design or 
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optimize for use on such a fuel. As described above, we agree with EPA that this provision could 

help auto manufacturers meet their CAFE requirements. 

BIO and its members look forward to working with EPA and the affected parties of this 

rulemaking to ensure implementation of a final Tier 3 rule that promotes the continued 

development of the biofuels industry as expressed in these comments, while complimenting 

other transportation regulatory requirements, including under the RFS and CAFE. 

Organization: Energy Future Coalition and Urban Air Initiative

Together, we file these comments in response to EPA’s questions in the Proposed Rule about 

whether to approve “an alternative certification fuel such as a high-octane 30 percent ethanol by 

volume (E30) blend” to enable more efficient engine design. Our comments will show not only 

the advisability of approving a mid-level ethanol blend certification fuel, but also the need to 

facilitate its use in order to comply with EPA’s obligation to regulate mobile source air toxics 

(MSATs or “hazardous air pollutants”). We hope EPA will take advantage of this opportunity to 

usher in a new era of cleaner, higher-efficiency fuel, improving the lives of millions of American 

citizens and protecting both public health and the environment. 

The Proposed Rule will deliver substantial economic, health, and environmental benefits to the 

nation; however, it inadequately considers the opportunity to enlarge those benefits and save tens 

of billions of dollars annually by facilitating a gradual shift in the content of motor vehicle fuel 

for light-duty vehicles. A mid-level ethanol blend fuel, created by splash-blending ethanol with a 

gasoline blendstock that meets current standards, would maximize benefits to air quality and 

public health, automotive performance, and consumer costs: 

As another example, the Proposed Rule notes, “as the ethanol level increases, the volatility 

increase caused by blending ethanol with gasoline begins to decline, such that at E30 there is 

only about a 0.5-psi RVP increase.” Indeed, a recent study by a team from Ford Motor Company 

and AVL Powertrain Engineering, Inc. concluded that RVPs match that of base gasoline at 

ethanol concentrations of 30%. This has positive implications for the cost and ease of 

compliance with the Proposed Rule. 

- Automotive performance: As the Proposed Rule notes, the use of a 30% ethanol blend “could 

help manufacturers that wish to raise compression ratios to improve vehicle efficiency, as a step 

toward complying with the 2017 and later light-duty greenhouse gas and CAFE standards.” The 

Ford/AVL team reviewed 10 properties of ethanol blends and concluded that “a mid-level 

ethanol blend (greater than E20 and less than E40) appears to be attractive as a long-term future 

fuel for the US, especially if used in vehicles optimized for such a fuel.” Despite the lower 

energy content of ethanol, in an optimized vehicle with an E30 blend, vehicle fuel economy and 

range can be maintained. An E30 blend in an engine designed to use that fuel would have 

“ridiculous power and good fuel economy,” one senior automotive engineer said. 

- Consumer costs: Numerous economic analyses suggest that the replacement of gasoline with 

ethanol reduces the cost of gasoline. A recent study at Louisiana State University, for example, 

found that each additional billion gallons of ethanol reduces gasoline prices as much as $0.06 per 
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gallon. Considering U.S. ethanol production in 2010 was more than 13 billion gallons, this would 

suggest savings of up to $0.78 per gallon of gasoline. Since Americans consume more than 130 

billion gallons of gasoline annually, this amounts to more than $100 billion a year in savings. 

Increased ethanol use would further reduce gasoline consumption, increase those savings, and 

lessen the nation’s vulnerability to economic disruption due to fluctuations in oil prices. 

For all these reasons, we commend EPA for requesting comment on whether it should approve 

“an alternative certification fuel such as a high-octane 30 percent ethanol by volume (E30) blend 

for vehicles [automobile manufacturers] might design or optimize for use on such a fuel.” Our 

answer to this is an emphatic ‘yes.’ But in order to achieve this environmentally sound and 

technologically progressive result, EPA must remove certain hurdles erected by the current 

regulatory regime, described below in Part II. 

EPA Leadership Is Needed on Fuel Content for Certification and Consumer Use. In its Proposed 

Rule, EPA requests comment on whether the Agency should approve “an alternative certification 

fuel such as a high-octane 30 percent ethanol by volume (E30) blend for vehicles [automobile 

manufacturers] might design or optimize for use on such a fuel.” Our answer to this is an 

emphatic ‘yes.’ But in order to achieve this environmentally sound and technologically 

progressive result, EPA must remove certain hurdles erected by the current regulatory regime. 

Under current EPA regulations, automobile manufacturers must show that a fuel is 

“commercially available” before the Agency will approve it for emissions and fuel economy 

certification. In its proposed Tier 3 Rule, EPA states that the fuel must “be readily available 

nationwide” to meet this standard and that the onus is on automobile manufacturers to make this 

showing. However, EPA also asks for comment on whether this standard is appropriate. In the 

case of a new mid-level ethanol blend, we believe that this standard is not appropriate. 

Automobile manufacturers are not in a position to ensure that a fuel is available to consumers 

nationwide. The market will not produce and distribute a fuel until there are vehicles that run on 

it, and automobile manufacturers will not mass-produce vehicles optimized to run on a new fuel 

without assurance that these vehicles can be certified on that fuel, and that the fuel will be 

available to consumers. Moreover, Congress has prohibited the introduction of commercial fuel 

that is not already “substantially similar” to an existing certification fuel, so even if automobile 

manufacturers were capable of creating a market for a new fuel by themselves, they would not be 

allowed to do so until that fuel, or one like it, had already been approved as a certification fuel. 

The current regulatory regime thus imposes a catch-22 on the industry: The fuel necessary for 

the next generation of motor vehicle engines cannot be introduced into the market until it is 

approved as a certification fuel, and it cannot be approved as a certification fuel until it is 

available in the market. EPA should take the initiative to solve this collective action problem by 

(1) approving for new motor vehicle certification a high-octane, mid-level ethanol blend, subject 

to the environmentally relevant parameters discussed below, (2) ensuring that such fuel can be 

made commercially available, and (3) removing the regulatory disincentives that currently inhibit 

the development of efficient vehicles optimized or dedicated to operate on this fuel.

A market shift from current light-duty motor vehicle fuel to a mid-level ethanol blend would 

result in numerous benefits to the environment, to American drivers, and to the public at large. 

Increasing the ethanol content of fuel would reduce the United States’ dependence on foreign oil 
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and achieve corresponding benefits to national security. A mid-level ethanol blend would 

provide desirable gains in clean octane, enabling better engine performance and efficiency. 

Finally, and of primary significance for the purpose of these comments, adding ethanol to fuel 

would allow EPA to satisfy its statutory obligation to regulate air toxics in motor vehicle fuel by 

reducing aromatic hydrocarbons that naturally occur in gasoline and are added to motor vehicle

fuel as an octane enhancer. Reducing these harmful additives by adding octane-rich (and less 

expensive) ethanol would substantially reduce the environmental impact of fuel emissions with 

direct health benefits and lower pollution control costs to the public, especially in urban areas. 

EPA Should Approve a Splash-Blended Mid-level Ethanol Blend Certification Fuel. Requiring 

automobile manufacturers to demonstrate that a fuel is “commercially available” as a 

precondition to EPA’s approval of it as a certification fuel stifles technological progress and 

blocks environmental benefits, as described above. By seeking comment on this requirement, 

EPA opens the door to the kind of Agency leadership on air toxics that Congress contemplated in 

section 202(l). EPA should make the first move in this direction by approving a splash-blended 

mid-level ethanol blend as an optional certification fuel. In due course, EPA should require all 

new motor vehicles to be certified on this fuel and then phase down the aromatics content of fuel 

in response to its obligation to reduce MSATs. In other words, the Agency should over time 

make a mid-level ethanol blend the standard, rather than an alternative, certification fuel. 

It is important, however, to ensure that the quality of the gasoline portion of the fuel is not 

permitted to deteriorate before blending with ethanol, thereby reducing the environmental 

benefits of aromatics reduction. In its notice of proposed rulemaking, EPA asks for comment on 

whether the Agency needs “to specify more precisely the makeup of [a higher octane, higher 

ethanol content] fuel” in terms of “ethanol content, as well as other fuel parameters.” The 

answer is yes. Since ethanol contains only one molecule, with unvarying chemical properties, it 

is critical that, when regulating fuel blends for environmental purposes, EPA specify certain 

parameters of the gasoline “blendstock for oxygenated blending” or “BOB,” that is, the gasoline 

portion of the fuel to which ethanol will be added. This is crucial because the gasoline 

blendstock is the only portion of the fuel that has variable characteristics. 

As noted above, the components of motor vehicle fuel evaporate at different temperatures, and 

the components that evaporate at high temperatures have the worst environmental and health 

effects. 

Because ethanol, unlike gasoline blends, contains just one molecule, it has a single, relatively 

low, boiling point. Ethanol’s T50 is the same as its T90—78.4 degrees Celsius—this is the 

temperature at which every molecule of ethanol would evaporate at sea level. Standard gasoline, 

on the other hand, is capped at a T50 of 121 degrees Celsius and a T90 of 190 degrees Celsius by 

ASTM, a non-governmental standards-setting organization. (The ASTM limit is a ceiling, not a 

floor; refiners are free to create fuel blends with lower T90 values (and T50 values as low as 77 

degrees Celsius), and ethanol makes this possible.) In other words, standard gasoline contains 

much higher distillates than ethanol and is therefore more conducive to tailpipe pollution. Mixing 

ethanol directly with current blendstock for oxygenate blending (“splash blending”) reduces the 

distillation temperatures of the finished fuel proportionally, thereby reducing tailpipe pollution. 
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The Agency’s EPAct model, referred to in the proposed rule only with respect to CO2 emissions, 

purports to measure the effects of various fuel blends on many forms of pollution. However, 

EPAct does not model splash blending of ethanol with standard gasoline blendstock, but rather 

models what would happen if refiners were allowed to alter the gasoline portion of the fuel by 

adding dangerous levels of high-distillate aromatics before blending with ethanol. In other 

words, EPAct models the pollution effects of ethanol blends containing high-distillate gasoline 

formulations that are themselves not permitted to be sold as consumer fuel. 

In the real world, EPA should not allow refiners to make gasoline blendstocks more dangerous 

before mixing them with ethanol. If only the final fuel needs to maintain certain parameters such 

as octane and T50, T90, and endpoint distillation temperatures, refiners could make gasoline 

blendstocks dirtier and lower octane, thereby canceling out the performance and environmental 

benefits of ethanol. EPA should not permit this to happen. As the Agency noted with regard to 

E51-83, “only blendstocks (including butane and NGL) that meet [certain] specifications would 

ensure the final blend would always meet the standards.” We agree with the Agency that in 

blending ethanol into motor vehicle fuel, the use of previously approved blendstocks and 

“gasoline that has previously been demonstrated to comply with applicable EPA specifications . . 

. prevents inappropriate blending components from being used in the production” of the resulting 

ethanol blend. Maintaining current blendstock standards is also necessary to maximize the 

engine performance benefits of a mid-level ethanol blend. Thus, EPA should mandate that any 

mid-level ethanol blend approved for market and certification fuel be made up of (1) a certain 

percentage of ethanol by volume, and (2) a corresponding volume percentage of gasoline which 

itself meets all relevant EPA and ASTM standards. In other words, EPA should approve a 

“splash-blended” mid-level ethanol fuel. 

EPA Should Remove Regulatory Disincentives that Currently Impede the Production of Vehicles 

that Run on a Mid-Level Ethanol Blend. In the proposed rule, EPA requests comment on how the 

Agency might “provide an incentive for, or remove obstacles to, the development of highly 

efficient vehicles optimized for use on higher level ethanol blends.” EPA also requests comment 

on whether an adjustment is warranted in the compliance calculation for light-duty GHG 

standards. These two questions should be viewed through the same lens. EPA should remove 

current regulatory disincentives to the production of vehicles designed to run on a mid-level 

ethanol blend, while paving the way for a national transition to this fuel by incentivizing 

increased production of FFVs. These incentives can be achieved without relaxing GHG 

emissions standards, simply by allowing auto manufacturers to account for the life-cycle GHG 

benefits of ethanol in their GHG compliance calculation. 

In order to begin to phase in a cleaner, higher-ethanol fuel that significantly reduces air toxics 

and other dangerous pollutants, while at the same time helping manufacturers design more 

efficient engines to reduce GHG pollution, EPA should allow all vehicles capable of running on 

a mid-level ethanol blend (dedicated, optimized, or FFV) to be certified for purposes of GHG 

emissions and fuel economy on the new high-octane, mid-level ethanol blend. 

Organization: Volkswagen Group of America, Inc.

Other Fuel Properties 
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VW supports working with the Agencies on a higher octane/higher ethanol certification fuel that 

can be optionally used by the light duty fleet. Vehicles specifically designed for known fuels can 

take advantage of efficiencies available. VW sees value in ensuring the specially-designed 

vehicles have access to an analogous market fuel. EPA must then ensure that vehicles not 

designed for this fuel do not attempt to use it, i.e., gas station pump labeling must assist 

customers in choosing the proper fuel for their vehicle. VW supports a 9RVP E 15 and 9 RVP 

E30 created by splash blending the appropriate level of ethanol into gasoline. 

Organization: Ford Motor Company (Ford)

We also commend EPA on their forward-looking approach for future opportunities for increased 

vehicle efficiencies through the request for comments on a higher octane rated alternative 

certification fuel. Treating fuels and vehicles as a system is vitally important as fuel quality 

improvements are needed to enable the advance technologies that will be needed to meet 

requirements of the ONP as well as Tier 3. Thus, further modifications to the market fuel quality 

parameters (vapor pressure, elimination of the use of metallic additives, increased detergency 

requirements, increased octane rating for gasoline, and increased cetane rating for diesel) are 

necessary to allow for a complete integration of vehicles and fuels as a system. 

Alternative Certification Fuel: In the NPRM, EPA proposes to allow vehicle manufacturers to 

request approval for an alternative certification fuel such as a high-octane 30 percent ethanol by 

volume (E30) blend for vehicles designed or optimized for use on such a fuel. EPA requests 

comments on an alternative test fuel that is a “higher octane, higher ethanol content gasoline”. 

While we support the initiative for future collaboration between original equipment 

manufacturers (OEMs), government agencies and other stakeholders to maximize vehicle 

efficiency in tandem with use of renewable fuels, we believe that there is still further 

development needed on the higher ethanol/high octane certification fuel option. Additional 

information and recommendations concerning this proposal can be found in Part II (Fuels 

section) of this document. 

Recommendation: Ford strongly recommends that EPA pursue regulations and other measures to 

facilitate the introduction of higher octane rating market fuels, which offer the potential for the 

introduction of more efficient vehicles. Progress on this issue will be a key parameter for 

consideration in the “One National Program” mid-term evaluation process, as well as for all 

phases (current and future) of the medium and heavy-duty GHG and fuel economy standards. 

Alternative Certification Fuel Opportunity: As noted above, Ford supports the development and 

introduction of an intermediate level blend fuel (E16-E50), with a minimum octane rating of 91 

anti-knock index (AKI) that increases proportionally as ethanol is splash-blended on top of the 

base Tier 3 gasoline emission test fuel. The development of such a fuel would enable the first

steps to the development of a new generation of highly efficient internal combustion engine 

vehicles. We look forward to future collaboration with the EPA on this item. We recognize that a 

number of issues will need to be resolved in order to move this concept forward, but there is 

concurrence that it is important to work through the details to allow more efficient vehicles to be 

made available to American consumers. 
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In response to the request for comment, Ford provides the following observations and 

recommendations as outlined in the following section. Literature has shown that increased 

ethanol in gasoline paired appropriately with the resultant commensurate increase in octane 

rating of the final blend leads to future opportunities for increased engine efficiency and 

therefore, reduced GHG emissions. The addition of ethanol to gasoline blends has many 

potential benefits, which have been extensively studied10,11,12,13,14,15 (see Appendix A). 

Ethanol is a renewable fuel which displaces petroleum and has been shown to reduce wells-towheels CO2. Ethanol can be produced domestically, therefore offering the potential to support 

domestic energy goals. Advanced engine designs operating on ethanol (with increased octane 

rating) have a slightly higher thermal efficiency and produce fewer tank-to-wheels CO2 than 

engines operating on straight gasoline. If octane rating is allowed to increase with the added 

ethanol, there is opportunity to optimize the engine for further improvements in engine efficiency 

(see Appendix). In the U.S., the Energy Independence and Security Act of 2007 (EISA 2007) 

mandates 36 billion gallons of renewable fuels in use by 2022. Since starched-based ethanol is 

limited to 15 billion gallons in EISA 2007, excess ethanol has been exported to other fuel ethanol 

consuming countries. Ethanol has a lower vapor pressure than gasoline; however, the addition of 

ethanol at a concentration of about 10%-15% by volume increases the blended vapor pressure by 

approximately 1 psi. At levels above this range of ethanol, the vapor pressure of the resulting 

mixture begins to decrease. The decrease in vapor pressure allows for decreased evaporative 

emissions, however, too low vapor pressure can result in engine starting issues in colder 

climates. 

The higher octane number (109 Research Octane Number [RON] for ethanol versus today’s 

regular gasoline 91 RON) and higher heat of vaporization associated with gasoline-ethanol 

blends can improve engine efficiency through engine redesign and use of higher compression 

ratios. However, the oxygen content in ethanol can result in enleanment for engines with 

uncalibrated control modules due to the change in stoichiometric air/fuel ratio (A/F). For 

example, assuming E0 has a stoichiometric A/F of 14.6, this A/F then becomes 14 for E10, 9.9 

for E85 and 9.0 for E100. In addition, ethanol’s energy density is less than that of gasoline, with 

E100 having a net heating value (NHV) of 21 MJ per liter of fuel whereas gasoline has a NHV of 

33 MJ per liter of fuel. The difference in energy density results in reduced volumetric fuel 

economy of ethanol-gasoline blends versus pure gasoline in non-optimized engines. Even though 

ethanol’s higher octane rating can improve the thermal efficiency of the engine at knock limited 

operating conditions, the net result is degraded volumetric fuel economy and this is most 

pronounced in E85 blends, which has about 27% less energy per gallon than gasoline. 

However, increased octane rating from increased ethanol content has the potential to allow for 

fuel economy, performance and emissions improvements through more efficient engine designs. 

Raising the minimum octane rating requirement would allow manufacturers to design engines 

with greater thermal efficiency through higher compression ratios and/or smaller displacement 

turbo-charged engines. Current engines in the fleet could also benefit from the higher octane 

rating through more aggressive spark timing during certain driving conditions. High compression 

ratio engines are already found in Europe, where 95 RON fuel is typically available in contrast to 

the lower 87 AKI (approximately 91 RON) fuel that is most common in the US. The introduction 

of higher octane rated/intermediate level ethanol blend fuel would allow for a faster introduction 

of more efficient vehicle designs from Europe with lower CO2 emissions and increased 
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efficiency that are designed to operate on 95 RON (~91 AKI) market fuel without the need for 

significant design changes as for products destined for the U.S. market. 

Of course, there needs to be a long-term strategy for the introduction of such a fuel, and a 

number of phase-in issues must be addressed in the meantime. Protection grade fuel must remain 

available for those consumers with legacy products as the new alternative fuel is phased in. The 

current flexible-fuel vehicle (FFV) fleet can be used in the interim as the transition from lower 

(E10) to higher ethanol level blends occurs across the United States. The timing and details 

regarding the introduction of optimized vehicles dedicated to the use of the new fuel will need to 

be addressed as it becomes important to promote flexibility in this transitional timeframe. 

Considering the added complexity in the production of vehicles capable of greater than E10 or 

FFVs, continued incentives to build such vehicles will likely be necessary. EPA should consider 

an extension of the current FFV credit policy (F-factor) to allow credits to be generated for 

vehicles with the capability of operating with intermediate ethanol blend fuels. Considering the 

complexity and transitional nature of the entire scenario, such burden of proof with respect to 

fuel use should not be placed upon either the vehicle manufacturer or vehicle owner. 

Alternatively, such credits could be allocated based on national ethanol use beyond that which 

can be allocated to an E10 marketplace and then distributed to manufacturers based on sales 

volumes of capable vehicles. 

The inevitable quandary of sufficient fuel infrastructure must be also addressed. As observed in 

the literature cited in this document (see Appendix), sufficient nationwide availability of the 

next-generation blend must be assured as future fuels and engine technologies should progress 

synergistically, with a consistent, open dialogue between stakeholders and policymakers. 

The next-generation fuel must also be favorably valued by consumers in order to incentivize 

consistent use throughout the market. As stated above, FFVs offer an opportunity for current 

technology vehicles to bridge the gap until the new fuel is available in sufficient quantities 

throughout the market. Finally, to assist in the market introduction of the next-generation fuel to 

consumers, fuel certification must be addressed and aligned at a federal level. Ford recommends 

the use of market fuel specifications that are developed through ASTM working groups (ASTM 

D5798, ASTM D4806) as well as subsequent successful working groups. 

Recommendation: Ford strongly recommends that EPA pursue regulations and other measures to 

facilitate the introduction of higher octane rated market fuels, which offer the potential for the 

introduction of more efficient vehicles. Progress on this issue will be a key parameter for 

consideration in the “One National Program” mid-term evaluation process,16 as well as for all 

phases (current and future) of the medium and heavy-duty GHG and fuel economy standards. 

Organization: General Motors LLC (GM)

EPA Should Replace Flawed Regulations Governing Use of Alternative Test Fuels. GM agrees 

that alternative test fuel provisions in the current regulations at 40 CFR 1065.701(c) are flawed 

and cannot work in practice. For dedicated vehicles, the regulation requires that the new fuels be 

commercially available in the marketplace; in addition, the regulation appears to presume the 
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fuels would be widely available without any vehicles being available to use them, which 

underscores the unresolved “chicken and egg” dilemma. 

In addition, manufacturers would have to show that the vehicles will not run or be durable on 

standard test fuel. Alternatively, manufacturers could show that the vehicles would not meet 

emissions limits on standard test fuel (i.e., measured emissions would be “substantially 

unrepresentative”), all of which would likely make them practically unsellable. 

Were an OEM to petition to test using E15 test fuel under these provisions, meeting them would 

be very challenging. Rather than imposing unrealistic regulatory pre-conditions, EPA needs to 

replace them. GM would be happy to work with the agency to develop a workable process and 

criteria for access to alternative test fuels. 

Within the rulemaking, EPA puts forward the concept of producing “dedicated E30 vehicles or 

FFVs optimized to run on E30 or higher alcohol blends.” While there is no way to couple a FFV 

and an optimized vehicle together, GM supports the future of higher octane and higher ethanol 

content in order to provide a pathway to improved vehicle efficiency and lower GHG emissions. 

However, the use of an R-factor less than 1.0 discourages the voluntary use of any fuel with 

energy content less than that of the 1975 emissions certification fuel. 

Organization: Mercedes-Benz USA, LLC on behalf of Daimler AG

The synergy of increased efficiency, afforded by high octane and the reduced carbon intensity 

mid-blend ethanol can offer, along with gasoline direct-injection and other technologies, can 

provide remarkable reductions in CO2 output. Mercedes-Benz endorses the concept of a higher 

octane, mid-blend ethanol certification fuel such as E25, as suggested in the Tier 3 proposed 

rulemaking, and requests consideration of the aforementioned corporate annual CO2 burden 

reduction proposals.

Organization: National Corn Growers Association (NCGA)

The first principle is that the RFS volume of biofuels in the future should be met in order to 

preserve the 150 million metric tons of annual CO2 equivalent emission reductions attributed to 

the RFS 2 program by EPA. These emission reductions are directly dependent on the production 

of biofuels and not on the fuel economy of the light-duty on-road motor vehicle fleet. The 

volume of biofuels utilized is in turn dependent on having vehicles that are flexible-fuel capable 

and those certified on high octane mid-level blends plus a retailer infrastructure offering energycompetitive pricing. The Tier 3 proposal thus has a direct bearing on the availability of vehicles 

to implement the RFS. 

Further, we support the recognition that a high octane mid-level ethanol blend (MLEB) would 

help automakers achieve the 2017 and later GHG and CAFE standards. 

High Octane E30 Alternative Certification Test Fuel: EPA suggested the concept of producing 

“dedicated E30 vehicles or FFVs optimized to run on E30 or higher alcohol blends.” NCGA 

supports fuels with higher octane and higher ethanol amounts that provide a pathway to 
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improved vehicle efficiency and lower GHG emissions. It is important to establish the 

composition of a new fuel early to facilitate design and optimization. NCGA recommends two 

options for the base gasoline blendstock for oxygenate blending (BOB) and several options for 

ethanol content. For base gasoline or BOB, the options are conventional gasoline BOB or 

CBOB, an 88 research octane (RON) hydrocarbon that becomes regular E10 when blended with 

10 percent ethanol, and a high octane “premium” gasoline BOB or PBOB, a 91-93 RON 

hydrocarbon that becomes premium E10 when blended with 10% ethanol. Although EPA 

mentions 30 percent ethanol as a candidate blend, other ethanol blend rates such as E25 or E35 

may represent a more optimum blend for vehicle and engine design. 

NCGA does not believe that the alternative test fuel provisions at §1065.701(c) are practical 

since they assume that a new fuel would become widely available prior to the availability of 

vehicles designed to use it. Further, a specification for the new fuel is needed ahead of time as a 

guide for fuel providers and auto manufacturers. 

Were EPA to determine that some sort of “actual use” demonstration of the high octane high 

ethanol fuel is required, NCGA would look to recent EPA guidance on this subject. EPA, in its 

Draft Guidance for E85 Flexible Fuel Vehicle Weighting Factor for Model Year 2016-2019 

Vehicles, stated that the F-Factor (proportion of actual use) “...must be based on the projected 

use of the alternative fuel over the life of the ... vehicles.” If the determination of the amount of 

alternative fuel used requires the vehicles to reach full useful life first, then it is clear that EPA 

will have to offer guidance on what this F-Factor value would be because of the uncertainty of 

this value. 

EPA has the authority to ensure the availability of this new fuel formulation as the vehicles 

designed to use it become available if it believes such a fuel would enable meeting the 2017 and 

Later Model Year CAFE and GHG Emission regulation and the RFS regulation (8). Consistent 

with EPA’s expressed belief that improved engine efficiency and reduced GHG emissions would 

result from a high octane MLEB and engines designed for its use, we recommend that EPA 

consider requiring the nationwide availability of such a high octane fuel. 

Perhaps a more workable alternative would be to require a phase-in of all gasoline fueled light 

duty vehicles as FFVs beginning in 2017 (50% in 2017 and 100% in 2018). This approach would 

clearly communicate EPA’s support for the GHG reduction benefits of the RFS program, and 

would clear the way for FFVs to become the “bridge” to a new generation of vehicles designed 

and optimized to run on a higher octane MLEB. Requiring 2017 and later gasoline vehicles to be 

FFVs would remove any limits on ethanol usage, and would provide a clear incentive to service 

station owners to offer more gasoline/ethanol fuel choices through the use of blender pumps. 

One of the key impediments to additional biofuel use is the number of vehicles with flexible fuel 

capability to use blends above E15. With a current penetration of about 18 million vehicles, 

FFVs are still significantly less than 10% of the vehicle fleet. E85 is sold in approximately 3,000 

service stations, less than 10 percent of the 165,000 stations, not nearly enough to support 

increased ethanol consumption volumes under the RFS. It is our belief that if EPA required 2017 

and later vehicles to be certified as FFVs, automakers would more seriously consider petitioning 

EPA for a high octane MLEB. A preferred MLEB for both consumers and automakers would 

then likely emerge from this process. An FFV requirement would also eliminate any non-FFV 
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“misfueling” concerns with the 2017 and later fleet. Finally, requiring gasoline vehicles in 2017

and later model years to be FFVs would significantly enhance energy security in the United 

States by encouraging the use of renewable, domestically produced fuels. 

At least two major automakers have reported research programs evaluating advanced technology 

gasoline direct engines with high octane MLEBs.

Organization: Natural Resources Defense Council (NRDC)

Alternative, high-octane certification fuels must be sustainably produced and be the in-use fuel 

for vehicles certified on the fuel to receive greenhouse gas or fuel economy credits. 

Alternative, High-Octane Certification Fuels Must be Sustainably Produced and be the In-Use 

Fuel for Certified Vehicles to Receive GHG or Fuel Economy Credits. EPA proposes to allow 

automakers to certify vehicles on an alternative high-octane renewable-blend fuel. NRDC 

supports automaker efforts to reduce carbon pollution and increase fuel economy by optimizing 

their operation for clean fuels. However, an alternative, renewable certification fuel must be 

sustainably produced and available as the regular in-use fuel. NRDC opposes the adoption of 

E30 as a certification fuel in this rulemaking because today there is no clear timeline in which 

E30 made from sustainably-produced ethanol could be available on a national scale. Establishing 

a process to certify vehicles on E30 today would signal support for greater production of ethanol 

from food crops such as corn, which have significant environmental and economic risks. 

If a renewable, high-octane fuel can be produced on a large scale, it must be widely available. 

For an automaker to receive GHG emissions and fuel economy ratings based on the alternative 

certification fuel there must be certainty that the certified vehicle is being primarily operated on 

that fuel during use by the vehicle consumers. 

Organization: POET, LLC

EPA should finalize an optional E30 certification fuel, without unnecessary gating criteria. EPA 

proposes ‘to allow vehicle manufacturers to request approval for an alternative certification fuel 

such as a high-octane 30 percent ethanol by volume (E30) blend for vehicles they might design 

or optimize for use on such a fuel.’

An optional E30 certification fuel should be allowed and finalized as soon as possible. POET 

agrees with EPA that an E30 certification fuel ‘could help manufacturers that wish to raise 

compression ratios to improve vehicle efficiency, as a step toward complying with the 2017 and 

later light-duty greenhouse gas and CAFE standards,’ which ‘in turn could help provide a market 

incentive to increase ethanol use beyond E10 by overcoming the disincentive of lower fuel 

economy associated with increasing ethanol concentrations in fuel, and enhance the 

environmental performance of ethanol as a transportation fuel by using it to enable more fuel 

efficient engines.’
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An E30 certification fuel promotes the development of high-octane, clean-running vehicles that 

reduce toxic air pollutants and other health-based pollutants such as PM. The use of MLEBs also 

provides a clear pathway to meeting RFS mandates for biofuels use. 

However, EPA also references certain ‘gating’ criteria to be able to use an E30/MLEB 

certification fuel, including requirements to ‘[1] demonstrate that such a fuel would be used by 

the operator and would be readily available nationwide, [2] vehicles would not operate 

appropriately on other available fuels, and [3] such a fuel would result in equivalent emissions 

performance.’

Each of the three ‘gating criteria’ regarding the use of an E30/MLEB certification fuel is 

unnecessary and should be avoided. 

First, a mandate to demonstrate that ‘such a fuel would be used by the operator and would be 

readily available nationwide’ is unworkable, unnecessary, contrary to EPA’s treatment of other 

fuels and vehicles, and counter to EPA’s stated purpose of the Tier 3 rule. Practically, requiring 

that a fuel be ‘used by the operator’ is unworkable because an auto manufacturer cannot be 

expected to make a driver’s fueling choice for a vehicle that by design is intended to offer ‘fuel 

flexibility.’ Economics and preferences will dictate which available fuel a driver will select. 

Furthermore, this criterion is unnecessary because ethanol, and therefore gasoline blends 

containing ethanol, are less expensive and are projected to remain so for the foreseeable future 

according to the Energy Information Administration 2013 Annual Energy Outlook. So EPA 

should be comfortable that MLEBs will in fact be used in E30-optimized vehicles. 

A mandate that a fuel be ‘readily available nationwide’ is contrary to EPA’s treatment of other 

fuels and vehicles. For example, manufacturers are not required to demonstrate that ‘fuel’ for 

electric vehicles or fuel cell vehicles will be available nationwide to obtain certain benefits under 

EPA’s CAFE/light-duty vehicle rule. In fact, electric and fuel cell vehicles do not have a 

nationwide refueling availability. Just as automakers are not punished for the limited availability 

of electric and fuel cell vehicle ‘refueling’ stations, which is largely out of the automaker’s 

control, automakers should not be punished for pursuing vehicle technology that leads to lower 

emissions but similarly relies on the availability of fuel, which is provided by another party. 

Furthermore, a requirement that a fuel is ‘readily available nationwide’ is more punitive than, 

and inconsistent with, existing provisions for using an alternative certification fuel in existing 40 

CFR § 1065.701(c), which merely requires that the fuel in question must only be ‘commercially 

available.’ E10 is available nationwide, but gasoline refiners and producers have sought to limit 

the availability of E15 and higher-level ethanol blends. 

Additionally, a mandate that a fuel be ‘readily available nationwide’ is counter to EPA’s stated 

purpose of the Tier 3 rule. This requirement is counterproductive because it exacerbates the 

‘chicken-or-egg’ problem that alternative fuels already face: in order to successfully enter the 

marketplace, there must be both sufficient alternative fuel and vehicles available to use the fuel. 

EPA should do all that it can to promote and expand the use of MLEBs because they can 

effectively reduce particulate matter and other toxic air emissions covered by the Proposed Rule. 

Unnecessary gating criteria frustrate these emission reduction goals. 
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A gating criteria mandate to demonstrate that ‘vehicles would not operate appropriately on other 

available fuels’ is inappropriate as it would defeat the purpose of creating ‘flex-fuel’ vehicles. 

FFVs are specifically designed to be able to operate on multiple fuels. Gating criteria should not 

unnecessarily limit the flexibility that these vehicles are designed to provide. 

Finally, a gating criteria mandate that ‘such a fuel would result in equivalent emissions 

performance’ is unnecessary. EPA already requires that vehicles achieve specific emissions 

limits for pollutants (and some emission limits may be specifically tailored for individual fuel 

types while maintaining a high overall level of environmental protection). 

To address concerns regarding emissions on E30/MLEB-optimized vehicles when using ‘other 

available fuels’ and ‘equivalent emissions performance’ (i.e., gating criteria 2 and 3, above), an 

E30/MLEB-optimized vehicle could also be tested on the E15 certification fuel, for the purposes 

of demonstrating compliance with minimum emission standards. A similar approach is currently 

used for ‘E85’ flex-fuel vehicles where they are also currently tested on E0. 

If an E30/MLEB-optimized vehicle is not designed to be run on HLEBs, manufacturers should 

be allowed the option of using labeling to clarify that HLEBs should not be used in such 

vehicles. Such a labeling is similar to that used for ‘premium-only’ gasoline vehicles today, and 

should be sufficient to address any concerns regarding an E30 vehicle running on HLEBs. 

Two alternative certification fuels for FFVs should be available depending on what blend-range 

the FFV is optimized for. Within the Ethanol Fuel Family, a manufacturer should be able to use 

one certification fuel for vehicles designed to be run on HLEBs (E51-E85) and should be able to 

opt to use the E30 certification fuel for vehicles optimized for E30/MLEB blends. POET 

believes that these two certification fuels would be representative of in-use fuels for which 

MELB and HLEBs would be designed to operate and, pursuant to Clean Air Act Section 206, 

reflect ‘actual current driving conditions under which motor vehicles are used.’

Regarding vehicles optimized for E30/MLEBs, POET supports EPA’s proposal for an optional 

E30 certification fuel, as discussed above. POET believes that an E30 certification fuel would 

reflect actual, in-use fuels for which vehicles using MLEBs and the ‘actual current driving 

conditions under which motor vehicles are used’ pursuant to CAA Section 206. Furthermore, an 

E30 certification fuel would be ‘within the range of fuel mixtures’ that are ‘expected to be found 

in use.’

In fact, ethanol cost-effectively provides a high-octane, clean-burning fuel that is important for 

meeting recently-tightened corporate average fuel economy (CAFE) and greenhouse gas 

emissions standards promulgated by EPA. The Proposed Rule notes that MLEBs could ‘help 

manufacturers that wish to raise compression ratios to improve vehicle efficiency, as a step 

toward complying with the 2017 and later light-duty greenhouse gas and CAFE standards.’ 78 

Fed. Reg. at 29,825. 

Ethanol also provides other important energy security and economic benefits. Significant hikes 

in oil prices immediately preceded 10 of the last 11 U.S. recessions. Ethanol today makes up 
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approximately 10% of the gasoline market, expanding our fuel supply and adding diversity, 

which dampens the impact of fuel supply disruptions. Ethanol also supports over 365,000 U.S. 

jobs. 

Looking ahead, as more stringent emissions standards come into play, automakers will need 

higher-octane fuel to improve engine efficiency. Automobile engineers have found that ‘a midlevel ethanol blend (greater than E20 and less than E40) appears to be attractive as a long-term 

future fuel for the U.S., especially if used in vehicles optimized for such a fuel.’ Furthermore, 

according to a recent MathPro Refinery study, increasing the fuel octane to 92 AKI from 88 AKI 

would result in significant cost savings. Ethanol represents the most likely source for achieving 

the fuel mix needed. 

As noted above, ethanol costs less than gasoline and expands the available domestic fuel supply. 

Additionally, improving the fuel distribution infrastructure to accommodate higher ethanol 

blends is cost-efficient. A recent Stillwater Associates study estimates the cost of updating pump 

infrastructure nationwide to accommodate higher blends such as E30 at a range of 0.0024 cents 

per gallon to 0.0056 cents per gallon on a 15-year amortized basis. 

Organization: Governors’ Biofuels Coalition

Consequently, we commend the EPA for acknowledging the use higher-octane E30 blends. The 

Coalition, however, respectfully recommends that EPA make the following changes to its final 

Tier 3 rule:

EPA should indeed establish an E30 certification fuel for model year 2017 and beyond. In 

answer to the Agency’s questions about the “appropriateness” of the current rules concerning 

approval of new certification fuels, the burdens of commercializing such a fuel should not be 

placed on the automakers as the relevant rule currently requires, since they have no control over 

the fuel manufacturing or distribution system. Instead, EPA should follow the successful 1970s 

transition from leaded to unleaded gasoline. 

Organization: Growth Energy

Demonstration of Ethanol’s Emissions Benefits and Growth Energy’s Support of a Workable 

E30 Certification Fuel: We wholeheartedly agree with EPA’s assessment that the proposed 

standards “represent a ‘systems approach’ to reducing vehicle-related exhaust and evaporative 

emissions by addressing the vehicle and fuel as a system.” Growth Energy made substantive 

comments in this regard on the Agency’s proposed Greenhouse Gas Emissions and Corporate 

Average Fuel Economy Standards for 2017 and Later Model Year Light-Duty Vehicles aimed to 

aid the automakers as they design the next generation of vehicles to take advantage of ethanol’s 

octane and emissions properties, as well as a means to achieve the goals of the RFS. Numerous 

studies have shown that as our nation moves to smaller, higher-compression engines, higher 

octane fuels using ethanol will be required. These higher-octane fuels using ethanol should not 

be more expensive – like today’s premium. Later in these comments we present the results of a 

study that shows these fuels will likely be lower cost than today’s regular. EPA should insist that 
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refineries and fuel producers not reduce the quality of our nation’s fuel and potentially jeopardize 

the nation’s air quality. 

In particular, Growth Energy fully supports the use of E15 emission certification fuel and the 

introduction of a high octane, low-emission E30 certification fuel. We also have several concerns 

about some of the hurdles to the potential use of an E30 certification fuel. We also continue to 

stress the Agency’s importance to the deployment of higher ethanol blends into the marketplace 

in order to fulfill the goals of improving air quality, reduce greenhouse gas emissions as well as 

to achieve the RFS volumes. 

Growth Energy Supports a Workable, E30 Certification Fuel: Based on these findings, Growth 

Energy is very supportive of the Agency moving forward with an E30 certification fuel for 

emissions; however, we have significant concerns about some of the unnecessary hurdles that 

automakers would experience in order to use such a fuel based on EPA’s proposal. 

First, a requirement that the fuel be readily available nationwide is not workable. The distribution 

of fuels is largely dependent on some of ethanol’s fiercest critics in the oil industry that continue 

to stifle the growth of any blends of ethanol above 10 percent. EPA should not hold the 

automakers accountable for the oil industry’s effort to limit the availability of these fuels, and 

instead, should either allow the automakers to immediately certify their vehicles on E30 or 

otherwise require that it be made available nationwide. 

Secondly, as we have shown, midlevel ethanol blends make significant contributions to our 

nation’s air quality. As such, EPA should consider using its authority and weight to make E30 

and other midlevel ethanol blends more available in the marketplace and should not penalize 

automakers for making vehicles capable of using such fuels. By requiring automakers to 

“demonstrate that vehicles would not operate appropriately on other available fuels” would run 

completely counter to their already well-established FFV production and the intent of making a 

Flexible Fuel vehicle. 

Growth Energy is also concerned that the R-Factor of 0.6 in the current fuel economy equation 

could also prevent automakers from using an E30 certification fuel option because of its impact 

on the fuel economy standards. The current factor is based on the use of older engine technology 

using ethanol-free gasoline. Based on information contained in the docket for the proposal 

(Aaron Butler, “Analysis of the Effects of Changing Fuel Properties on the EPA Fuel Economy 

Equation and R-Factor”), a higher R-factor of 0.8 – 0.9 would be more accurate and may 

encourage automakers to use an E30 test fuel. 

Finally, while we believe it is essential to remove these hurdles in order for automakers to use 

E30 as a certification and in-use fuel; we do, however, want to offer the agency the benefit of the 

extensive work and research we have done to get an in-use high octane, low-emission fuel into 

the national marketplace. Growth Energy commissioned two studies to look at both the refining 

cost, and distribution costs of developing a 92 Anti-Knock Index (AKI), E30 gasoline. These 

studies found that an E30 high octane blend can be produced for less than the cost of current 

gasoline, and that the development of the infrastructure over time is very affordable. Specifically, 

a 92 AKI E30 can be produced for between $11.7 billion and $30.8 billion per year less than the 
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cost of current 88 AKI regular gasoline. Additionally, the costs to develop infrastructure at 

terminals and gas stations across the country ranged from $0.0024 to $0.0056 per gallon on a 15-

year amortized basis. The complete studies are attached and are briefly summarized here:

MathPro Refinery Study Shows E30 is Less Expensive Than Today’s Gasoline: The MathPro 

Refinery study [This study is can be found in Docket number EPA-HQ-OAR-2011-0135-4681-

A4.] employed a linear programming (LP) model of the U.S. refining sector to estimate the main 

economic effects in the U.S. refining sector (including changes in the refining costs of 

transportation fuel) and on consumers of future fuel standards requiring the use of 92 AKI 

gasoline in HiTech vehicles. The refinery LP model incorporates the molar concentration 

blending method to represent ethanol’s blending octane in the various ethanol/hydrocarbon BOB 

blends considered. This method produces estimates of the effective blending octane of ethanol in 

given ethanol/BOB blends that are functions of the molar fraction of ethanol in the blend, the 

octane of the BOB, and the octane of neat ethanol (109 RON/90 MON). After calibrating the 

refinery LP model to replicate reported operations of the U.S. refining sector in 2011, MathPro 

used the model to assess alternative assumptions on how the new fuel economy standards and 

increased ethanol use in the target years would affect the volume of U.S. gasoline exports in 

those years. They estimated the effects on refining economics and consumer costs of the various 

92 AKI ethanol blend options by comparing the estimated costs returned by the refinery model in 

the 92 AKI Study cases with those in the corresponding 88 AKI Reference cases. Finally, they 

developed estimates in this manner for each of two assumed ethanol price scenarios: Low 

ethanol price: energy parity (¢/K BTU) with the wholesale price of 88 AKI E10, and High 

ethanol price: volumetric parity (¢/gal) with the wholesale price of 88 AKI E10. MathPro 

determined that the impact on the cost of transportation fuel was that the 92 AKI gasoline would 

be between $11.7 billion per year (ethanol at volumetric parity) and $30.8 billion per year 

(ethanol at energy parity) less than the current AKI 88 regular gasoline. 

Stillwater Associates Marketing and Distribution Study Shows E30 Infrastructure is Very 

Affordable: Stillwater Associates examined the marketing and distribution costs of widespread 

distribution of E30 fuel to 2017 and later motor vehicles (and FFVs). Marketing and distribution 

costs consist of bulk transport of additional ethanol, modifications to terminals that store and 

blend ethanol with gasoline, and modifications to gasoline stations. Stillwater modeled three 

cases. In the first case, it was assumed that E30 would be blended at the terminal and delivered to 

the station. Both terminals and stations would incur costs because they are not currently capable 

of delivering E30 except for a limited number of Midwest localities. The cost of this case is 

estimated at $3.5 billion, an average of $37 thousand per participating service station 

or$.0024/gallon on a 15-year amortized basis. The second case recognizes that gasoline quality 

regulations could drive a different solution. This second case looked at a combination of terminal 

blending and service station blending. The case recognizes that in regions where Reid Vapor 

Pressure (RVP) is controlled by reformulated gasoline regulations or by State Implementation 

Plans, current gasoline can be blended with fuel ethanol through a “blender pump” at the service 

station to make E30 without requiring a special E30 blendstock. In the Conventional Gasoline 

areas where RVP is subject to the 1-psi waiver, the E30 would have to be blended with a 

separate gasoline blendstock at the distribution terminal and delivered to the gas station. The cost 

of the second case is estimated at $5.8 billion, an average of $62 thousand per participating 

service station or $.0040/gallon on a 15-year amortized basis. The third case examined the cost 
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of doing all the E30 blending at the service station through blender pumps and assumes the RVP 

regulatory issues for E30 have been addressed. This option provides the retailer with the greatest 

level of flexibility for offering different blend levels, but also has the highest cost. The estimated 

cost of this case is $8.1 billion, or $87,000 per participating station. Spread over the 15 year life 

of the equipment, the cost of the changes is estimated to be $0.0056 per gallon. 

Organization: INEOS Bio

INEOS Bio is helping develop new and innovative ways to help fuel America and the world; 

providing cleaner burning cellulosic ethanol that helps reduce greenhouse gas emissions and 

provide more sustainable sources of fuel and energy. Achieving our nation’s goals of less 

dependence of foreign sources of oil and cleaner fuels will require our economy to transition to 

sustainable energy resources and higher levels of energy efficiency. Toward this end, federal 

policy and regulations—including the proposed rule as well as the federal Renewable Fuel 

Standard (RFS) and EPA’s consistent support and implementation of that policy—play an 

important role in helping to drive the commercialization of these technologies. The importance 

of federal policy is particularly critical in the transportation fuel sector. The U.S. transportation 

system is overwhelmingly and unsustainably reliant on petroleum fuels. These traditional fuels 

are a large component of the U.S. greenhouse gas (GHG) emissions inventory and our 

overdependence on foreign sources of energy. Rapid transition to more alternative transportation 

fuels is essential to reducing GHG emissions and reducing U.S. reliance on foreign sources of 

energy. 

INEOS Bio also supports EPA’s proposal to allow vehicle manufacturers to request approval for 

an alternative certification fuel such as a high-octane E30 blend for vehicles they might design or 

optimize for use on such a fuel. INEOS Bio is aligned with EPA’s assertion in the proposed rule 

that “[t]his could help manufacturers that wish to raise compression ratios to improve vehicle 

efficiency, as a step toward complying with the 2017 and later light-duty greenhouse gas and 

CAFE standards. 

We commend EPA’s efforts to transition the emissions test fuel to better reflect the current and 

future in-use fuel as it begins to contain greater volumes of biofuels resulting from the continued 

development and commercialization of biofuels and increased RFS volumes in the market. 

INEOS Bio believes that EPA should work to set the emissions test fuel to promote the highest 

achievable level of ethanol and octane in the U.S. fuel supply and thus lower the maximum 

aromatics and lowest additive concentration (LAC) content in gasoline accordingly. This action 

would help EPA meet one of its stated goals of this rulemaking to address the impacts of motor 

vehicles and fuels on air quality and public health without increasing gasoline prices. To this 

end, we believe the final rule should allow for ongoing and greater use of E85 and E15, as well 

as the transition to higher blends of ethanol and advanced biofuels. 

INEOS Bio also supports EPA’s proposal to allow vehicle manufacturers to request approval for 

an alternative certification fuel such as a high-octane E30 blend for vehicles they might design or 

optimize for use on such a fuel. As described above, we agree with EPA that this provision could 

help auto manufacturers meet their CAFE requirements and further displace aromatics content in 

gasoline. The benefits of Tier 3 that include lower sulfur, aromatics reductions, combined with 
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higher octane and increased use of renewables are significant, and I urge you to work to finalize 

this standard as soon as possible and subsequently include them in any future joint proposals 

such as CAFÉ, and National Program standards. 

Organization: International Council on Clean Transportation (ICCT)

The draft proposal requested comments on the use of E30 in certification testing: ‘We are 

proposing to allow vehicle manufacturers to request approval for an alternative certification fuel 

such as a high-octane 30 percent ethanol by volume (E30) blend for vehicles they might design 

or optimize for use on such a fuel.’

The ICCT is supportive of all ways to increase efficiency. In particular, the ICCT would strongly 

support increasing the minimum required octane for all gasoline.

Despite this, the ICCT could support the E30 provision only if the vehicles actually used E30 the 

vast majority of the time in-use. However, this would create major infrastructure difficulties: 

how would the E30 infrastructure be developed in advance of offering E30-capable vehicles? It 

also has potentially troubling consequences related to food-based high-iLUC ethanol, as 

discussed above with respect to E15. 

An entirely new infrastructure would be needed for E30, which means a huge chicken-and-egg 

problem. Just like with E85, one way to attempt to solve this is to offer credits to E30 vehicles, 

whether or not they actually use E30 in-use. The ICCT is extremely concerned that this will 

become another loophole, with large credits against the CO2/CAFE standards granted and little 

use in the real world, reducing the benefits of the standards. Our concerns are magnified by the 

recent EPA Manufacturer Guidance Letter on E85 usage, which proposed to grant flexible-fueled 

vehicles a 20% E85 usage rate (F-factor), even though E85 usage in the real world has remained 

steady at 1.1% since 1998. 

Our infrastructure concerns are exacerbated by the fact that E30 has 10% lower energy content 

than gasoline. Certainly some of this can be recaptured with higher efficiency, but it won’t be a 

10% efficiency improvement. Thus, customers will be able to travel further on gasoline (or E10 

or E15) than with E30, unless the vehicle is designed so that it does not run well on E10 or E15. 

Which raises another concern with vehicles designed for E30. A recent SAE paper on the 

impacts of ethanol blends reviewed what happens when a vehicle designed for E30 is run on 87-

octane gasoline: 

‘With engine downsizing, the reduction in full load torque with regular grade 91 RON fuel will 

be proportional to the amount of downsizing, and can result in unacceptable vehicle performance 

attributes for aggressive levels of downsizing.’

This loss of performance on regular fuel just makes the chicken-and-egg problem worse. Engines 

that require E30 are going to be a tough sell in the market. 
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Given the infrastructure concerns, E30 must offer substantial efficiency benefits to justify the 

investment in a new infrastructure. Thus, the key question is: What is the efficiency benefit of 

running on E30 compared to alternative technologies? The Stein 2013 SAE paper concluded: 

‘From an engine standpoint, the primary motivation for increasing ethanol content is improved 

knock resistance’. However, high EGR rates also offer improved knock resistance. If E30 

basically duplicates the benefits of boosted-EGR, it is hard to see how creation of a new 

infrastructure can be justified. 

Given all of the above, E30 should only be allowed if the manufacturer can demonstrate that the 

vehicle will almost always be refueled with E30 in-use. Given the historical abuse of similar 

provisions, such as FFV credits and the recent proposal for 20% F-factor for FFVs, the ICCT is 

very concerned about the potential to also abuse this provision. 

The ICCT is also concerned about the revision to use E-15 for test fuel. This is acceptable for 

certification vehicles, but it appears the EPA is also proposing to use E-15 for fuel economy 

testing. Fifteen percent ethanol provides significant evaporative cooling in the cylinder, which 

would allow manufacturers to make modifications to improve fuel economy in the test cycles, 

but which would not necessarily be achieved end use.

Organization: Marathon Petroleum Company LP (MPC)

Proliferation of Test Fuels: Part of EPA’s goal in modifying the certification fuel for Tier 3 was 

to reduce the number of certification fuels manufacturers would need to use to test their vehicle 

fleet. This goal seems to be lost as EPA is proposing to “allow vehicle manufacturers to request 

approval for an alternative certification fuel such as a high-octane 30 percent ethanol by volume 

(E30) blend for vehicles they might design or optimize for use on such a fuel. This could help 

manufacturers that wish to raise compression ratios to improve vehicle efficiency, as a step 

toward complying with the 2017 and later light-duty greenhouse gas and CAFE standards (2017 

LD GHG). This in turn could help provide a market incentive to increase ethanol use beyond 

E10 by overcoming the disincentive of lower fuel economy associated with increasing ethanol 

concentrations in fuel, and enhance the environmental performance of ethanol as a transportation 

fuel by using it to enable more fuel efficient engines.” Allowing each manufacturer the option to 

request approval of an alternative certification fuel could have significant impact on market 

dynamics. One can imagine a proliferation of boutique fuels necessary to support each individual 

manufacturer so that their vehicles can actually deliver the fuel efficiency as tested. This 

approach does not fit with the extensive, fungible fuel system that currently exists nor does it 

account for the limited fuel options available at service stations due to underground storage tank 

configuration and space availability. How does EPA expect to steward such a program and who 

would be responsible for determining the cost, well-to-wheel emissions, etc? One could image an 

engine that is optimized on an alternative certification fuel but would not deliver anywhere near 

the efficiency on in-use fuels so regarding alternative fuel availability, what would be the market 

threshold for EPA to consider allowing a manufacturer to use an alternative certification fuel? 

Organization: National Association of Convenience Stores (NACS) and Society of 

Independent Gasoline Marketers of America (SIGMA)
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Neither stakeholders nor regulators can predict all future changes in gasoline vehicle 

technologies or in-use fuels. The proposal contains specific specifications for high-octane 

formulations, but specifies that these fuels would be ethanol-based, such as E30. Other highoctane fuel formulations would require different fuels to undergo a potentially lengthy and 

expensive petition process for approval as test fuels.6 The final rule should not pick winners and 

losers in this regard. Ethanol may be the octane of choice at present, but EPA should allow for 

and encourage new fuels to come to market rather than impose artificial impediments to 

innovation. 

Organization: National Marine Manufacturers Association (NMMA)

NMMA testified at the CARB Board hearing requesting that the board also allow for the use of 

an alternative California certified advanced biofuel, if available. 

EPA requests comment regarding an option that would allow vehicle manufacturers to certify 

using a 30 percent by volume ethanol blend (E30) in recognition that E85 has not met EPA’s 

expectations and to encourage light duty vehicle manufacturers’ efforts to continue to determine 

what might be the optimal ethanol content. Given the large difference in oxygen content between 

E10 and E30 this approach will only cause further confusion and misfueling of marine engines 

when E30 reaches the marketplace, as would appear to be inevitable based on EPA’s proposal. 

This bifurcated approach of allowing E10, E30 and E85 in the marketplace does nothing to 

address the root problems associated with ethanol-enhanced fuels: ethanol is not gasoline. 

Organization: Renewable Fuels Association (RFA)

We support the proposal allowing vehicle manufacturers to request approval for an alternative 

certification fuel. 

The RFS2 calls for the continuing increase of ethanol content in gasoline. RFA supports the 

continued oversight by EPA on upcoming vehicle and fuel technology (specifically, recent 

research that suggests increasing the ethanol content in gasoline commensurate with 

improvement in octane can provide a vast improvement in vehicle efficiency, fuel economy and 

emissions). The auto industry has requested the use of increased ethanol content with increased 

octane in an effort to achieve future requirements for the reduction of greenhouse gas emissions. 

(Auto Alliance letter dated October 2013.) Further, the RFA commissioned a study of future 

influences and importance of fuel octane on future engine developments by Ricardo. Auto 

manufacturers will continue to build vehicles reliant on liquid motor fuels that rely on newly 

developed engineering improvements to address converging regulatory requirements for 

reductions in greenhouse gas emissions and pollutants. Ricardo concludes that “during the next 

decade internal combustion engines will become significantly more efficient due to pressures 

from regulatory and consumer preference. Similarly, higher minimum fuel octane number will 

facilitate the engine technologies that will boost specific power and engine efficiency. Future 

powertrain solutions will have a natural thirst for higher octane fuels.” 

Extensive research is being completed by Original Equipment Manufacturers and others to 

further understand the benefits to increasing ethanol content in the current motor fuel pool. 
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The most significant benefit of higher ethanol blends is the boost to the fuel blend’s octane 

rating, nearly a 4 to 7 Research Octane Number increase from an additional 10 to 20% ethanol. 

A recent Ford Motor Company publication concludes “higher minimum octane ratings for 

regular-grade fuel would enable higher compression ratios in future vehicles and is an 

opportunity to provide greater engine efficiency and meet increasingly stringent fuel economy 

regulations and expectations. Additionally, the change could benefit all vehicles powered by 

spark-ignited engines, including PFI and DI engines, hybrid electric vehicles (HEVs), and plugin hybrid vehicles (PHEVs).” 

This newly developing evidence suggests that ethanol’s contribution to the octane level of the 

gasoline pool may only beginning to be realized; additional and greater benefits of using ethanol 

to increase gasoline’s octane provide benefit beyond optimum performance. 

However, we are concerned that EPA’s proposed criteria for acceptance of a petition for an 

alternative certification fuel may be unrealistic and could discourage automakers from pursuing 

such a petition. Specifically, the proposed conditions that an automaker must “...demonstrate 

that such a fuel would be used by the operator and would be readily available nationwide,” and 

that “...vehicles would not operate appropriately on other available fuels” may severely limit the 

automakers’ ability or desire to utilize the alternative certification fuel petition process. 

Organization: Mercedes-Benz USA, LLC on behalf of Daimler AG

Mercedes-Benz acknowledges the EPA’s request for comment on the incorporation of a higher 

octane, mid-blend certification fuel such as E25 as a key enabler for GHG reduction. Octane is 

the single most important property of gasoline when determining engine design. Higher octane 

fuels permit higher compression ratios which directly improve efficiency while downsizing 

engines also results in greater fuel efficiency. The optimized combination of those two actions 

with gasoline direct-injection provides remarkable gains in fuel economy but requires high 

octane market fuel - higher octane than is available today. Additionally, higher octane, 

traditionally provided through selective petroleum refining and blending, can be further 

increased through the addition of ethanol in blends between 20-25 percent by volume. This 

powerful fuel enjoys both reduced carbon intensity as well as the renewable aspects of ethanol. A 

vehicle equipped with a powertrain which is optimized for a high-octane, mid-blend ethanol fuel 

(hereafter referred to as ‘Tier 3 Fuel’) can simultaneously fulfill what the customer desires -

performance and economy, while reducing the environmental impact. Mercedes-Benz vehicle 

offerings include those with E25 capability in various global markets and could be introduced 

them to the US market if regulatory and commercial conditions warrant. However, in order to 

harmonize with global markets, ethanol blend levels should be limited to 25% v/v as the effort to 

perform engine development, validation and certification for blends greater than E25 is quite 

substantial and necessary to determine hardware compatibility. 

One aspect not reduced is the customer expectation of performance, even in the wake of 

regulations mandating improved fuel economy. Thus, another key enabler in reducing 

greenhouse gas contributions while maintaining performance is increased octane and gasoline.

Octane is the single most important property in gasoline when determining engine design.
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Higher octane fuels permit higher compression ratios which directly improve efficiency.

Downsizing engines also results in greater fuel efficiency.

The optimized combination of these two actions with gasoline direct injection provides 

remarkable gains in fuel economy, but requires high octane market fuel, higher octane than is 

available today. Additionally, higher octane traditionally provided through selective petroleum 

refining and blending can also be further increased through the addition of ethanol and blends 

greater than 20 percent by volume. This powerful fuel enjoys both reduced carbon intensity as 

well as the renewable aspects of ethanol.

A vehicle equipped with a power train, which is optimized for a high octane mid-blend ethanol 

fuel can simultaneously fulfill what the customer desires, performance and economy, while 

reducing the environmental impact. In fact, Mercedes-Benz vehicle offerings include those with 

E-25 capability in various global markets, and can introduce them in the U.S. if regulatory and 

commercial conditions warrant.

To summarize, the synergy of mid-blend ethanol and higher octane based fuel in the 

proposed rulemaking opens the door to far greater possibilities in greenhouse gas and criteria 

emission reduction. Mercedes-Benz fully supports these proposed changes in certification and 

market fuel,

Organization: American Motorcyclist Association (AMA)

In its Tier 3, rule, the EPA proposes to change the certification fuel to E15, with an allowance for 

manufacturers to petition the EPA for an E30 certification. This, proposal, if promulgated, will 

create an environment where this country will have a bifurcated fleet of engines requiring 

different types of fuel. 

Organization: Truck and Engine Manufacturers Association (EMA)

EPA requests comment regarding an option to certify Tier 3 on-highway vehicles using a 30 

percent volume ethanol blend (E30). (78 Fed. Reg. at 29938.) In many respects, a bifurcated 

certification test fuel option to certify engines/vehicles utilizing an ARB-aligned (E10) 

certification test fuel, or a new alternative E30 certification test fuel, could provide a viable 

strategy for both RFS-2 compliance and engine/vehicle compatibility on a long term basis. 

Existing light-duty flexible-fuel vehicles would provide a market for E30 fuels until such time as 

engines/vehicles designed specifically for E30 would be available in the marketplace. If a 

manufacturer of a gasoline-fueled nonroad, motorcycle, heavy-duty on-highway engine 

determined there was sufficient customer interest, unique E30-certified products could be 

developed and marketed utilizing the alternative E30 certification test fuel. 

EMA recommends that EPA work with industry to identify and implement the appropriate 

ethanol content for such an alternate certification test fuel. 

Our Response:
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We received a large number of comments regarding our statement that manufacturers 

under certain situations could utilize an existing regulatory provision, 40 CFR 1065.710(c), to 

petition the Administrator for approval of an alternative test fuel such as a higher octane, higher 

ethanol content gasoline. Many of these comments focused on whether it is appropriate for EPA 

to use its authority to encourage or require widespread availability and/or use of such alternative 

fuels (e.g., higher octane blends, E30, isobutanol, etc.) These commenters appear to have 

misunderstood the purpose of the change in emission test fuel specifications. EPA is using its 

Clean Air Act section 206 authority to establish requirements for emission certification testing, 

including specifications of the emissions test fuels with which vehicles demonstrate compliance 

with emissions standards, in order to better reflect the ethanol content and other properties of inuse fuels. While we are taking action to limit sulfur content in in-use gasoline under authority in 

Clean Air Act sections 211(c)(1) and (2), we did not propose other changes to in-use fuels. Any 

action related to increasing the ethanol level of in-use fuels is outside the scope of this 

rulemaking.

The alterative certification fuel provisions are intended to allow manufacturers to request 

approval from EPA to certify vehicles that they design, build, and market to run on fuels other 

than those for which we have established certification test fuel requirements. In the past, the 

Agency has approved alternative fuels such as natural gas in response to petitions under this 

provision.

4.5.1.6. Changes to In-Use Gasoline Other than Sulfur Content

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Benefits of Lower RVP: 

In the summer of 2011, EPA sponsored a testing program that was designed to monitor 

evaporative emissions, canister loading profiles, and breakthrough emissions from extended 

multiday diurnal testing using 9 and 10 psi RVP fuels on 9 vehicles. In the spring of 2012, the 

Alliance and Global Automakers sponsored follow-on testing on a subset of the original vehicles, 

using 7 psi RVP E10 fuel in order to provide a more comprehensive set of data. The results of 

the study were published in Effects of 7, 9, and 10 psi Vapor Pressure Fuels on Multi-Day 

Diurnal Evaporative Emissions of Tier 2 and LEV II Vehicles, © SAE paper 2013-01¬1057, 

which was presented at the 2013 SAE World Congress in Detroit, MI. The light-duty vehicles 

used in the testing program were either certified to Tier 2 federal standards or the current most 

stringent evaporative emission standard in the U.S. – California’s Low Emission Vehicle (LEV 

II) Partial Zero Emission Vehicle (PZEV) standard. The test procedure for both phases of the 

testing program consisted of continuous monitoring over 14 days, which is 11 to 12 days beyond 

normal testing procedures, of the federal diurnal cycle for evaporative emissions (72° F to 96°

F). Figure 2.
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For all five vehicles tested, the 7 psi RVP fuel resulted in the least amount of hydrocarbon slip 

emissions from the vehicle’s carbon canister over the 14-day period, relative to the 9 and 10 psi 

RVP fuels. The data show that the 7 psi RVP fuel resulted in the least amount of evaporative 

emissions, with the 9 psi RVP fuel resulting in more evaporative emissions relative to the 7 psi 

RVP, and the 10 psi RVP resulting in the most hydrocarbon slip emissions. This demonstrates 

that appropriate reductions in fuel vapor pressure lead to reduced evaporative emissions. 

Meeting the more stringent evaporative emissions standards of Tier 3 is made possible through 

coordination of the “fuels and vehicle as a system” -- as consistently emphasized in the Tier 3 

NPRM. The reduction in summertime market fuel vapor pressure could benefit the entire car 

park from day one. In the NPRM, the EPA notes that “attention is needed to insure better in-use 

performance of current evaporative emissions.” A reduction in market fuel summertime vapor 

pressure would reduce the evaporative emissions performance of in-use vehicles and address 

EPA’s concern. 

Tier 3 Summertime Market Gasoline RVP Cap should be 8 psi (9 psi for E10) (per Federal VOC 

Control Season):

This would result in a maximum 9 psi RVP E10 market fuel, including the statutory one pound 

waiver. The most effective method of controlling prospective evaporative emissions in 

conventional gasoline use areas would be to move promptly to lower the maximum allowable 

RVP to compensate for the 1 psi waiver, perhaps to 8 psi. When the statutory mandate for the 1 

psi ethanol waiver is added, the fuel would then become 9 psi, as it was before the introduction 

of ethanol. Similar to EPA’s proposed market sulfur standard, this would bring about an 

immediate reduction in summer light duty evaporative emissions without waiting for the fleet to 

turn over. In addition, there would be reductions in evaporative emissions from all gasoline 

powered equipment, further enhancing the benefits of this approach. 

10 psi RVP gasoline hinders States seeking to avoid backsliding out of attainment, or 

neighboring states trying to meet State Implementation Plans (SIPS) to reduce criteria pollutant 

emissions. 

9 psi RVP Market and Test Fuel is Important to Avoid Emission Backsliding: EPA has an 

overdue obligation under the Congressional mandate in §209 of EISA (and implemented in 

section 211(v) of the CAA) which requires EPA to complete an anti-backsliding study, and 

promulgate fuel regulations to implement appropriate mitigation measures, if needed, based upon 

that study. EPA should complete that study immediately and undertake its mitigation rulemaking 

to address market fuel RVP. 

Organization: American Coalition for Ethanol (ACE)

Along those same lines, ACE recommends immediately extending the 1 lb waiver to blends from 

E11 to E50), as each additional percentage above 10% ethanol lowers Reid vapor pressure below 

that of nearly all gasoline sold in the United States. Adding ethanol to E10 will lower its 

volatility, and much in the same way EPA has suggested its rules might allow biobutanol to be 

added under an ‘averaging’ policy, we believe a similar approach would allow ethanol to be 

added to E10 to create compliant fuels with between 11 and 50 percent ethanol. Rather than 
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singling out E15, E30, or any other higher ethanol blend and requiring it to meet higher standards 

than other fuels, we believe that rules should welcome blends that are cleaner than the current 

industry standard E10. 

Organization: National Marine Manufacturers Association (NMMA)

EPA requests comment regarding the option of allowing the use of CARB E10 certification test 

fuel through model year 2019 with a Reid Vapor Pressure (RVP) of 10 psi (78 Federal Register 

29895). EPA currently provides a 1 psi waiver for E10, but this waiver will not apply to E15. 

NMMA recommends that the 1 psi waiver also be eliminated for E10. EPA finalized a rule in 

2010 that requires boat builders to meet stringent new evaporative emission requirements. 

California is currently in the process of finalizing a rule. In order to meet these new emission 

standards, marine engine manufacturers need a combination of new technology and a fuel with a 

minimum evaporation rate. 

Organization: General Motors LLC (GM)

But for the one pound waiver, E10 would be 9 psi or lower, which it is in many parts of the 

country. As discussed further below, for both vehicle performance and environmental benefits, 

we advocate that EPA reduce market fuel E10 RVP to 9 psi (by making the vapor pressure 

standard at 8 psi, which, with the E10 one pound waiver, would make E10 9 psi). 

Tier 3 Certification Fuel RVP and Marketplace Fuel RVP Should both be 9 RVP during the 

Summer VOC Control Season. Benefits of Lower RVP: In the summer of 2011, the EPA 

sponsored a testing program that was designed to monitor evaporative emissions, canister 

loading profiles, and breakthrough emissions from extended multiday diurnal testing using 9 and 

10 psi RVP fuels on 9 vehicles. In the spring of 2012, the Alliance of Automobile Manufacturers 

and the Association of Global Automakers sponsored follow-on testing on a subset of the 

original vehicles, using 7 psi RVP E10 fuel in order to provide a more comprehensive set of data. 

The results of the study were published in Effects of 7, 9, and 10 psi Vapor Pressure Fuels on 

Multi-Day Diurnal Evaporative Emissions of Tier 2 and LEV II Vehicles, © SAE paper 2013-

01-1057, which was presented at the 2013 SAE World Congress in Detroit, MI. The light-duty 

vehicles used in the testing program were either certified to Tier 2 Federal standards or the 

current most stringent evaporative emission standard in the U.S. – California’s LEV II Partial 

Zero Emission Vehicle (PZEV) standard. 

For all five vehicles tested, the 7 psi RVP fuel resulted in the least amount of hydrocarbon slip 

emissions from the vehicle’s carbon canister over the 14-day period, with the 9 psi RVP fuel 

resulting in more evaporative emissions relative to the 7 psi RVP, and the 10 psi RVP resulting 

in the most hydrocarbon slip emissions. This demonstrates that appropriate reductions in fuel 

vapor pressure lead to reduced evaporative emissions. 

Meeting the more stringent evaporative emissions standards of Tier 3 is made possible through 

coordination of the “fuels and vehicle as a system” as consistently emphasized in the Tier 3 

NPRM. The reduction in summertime market fuel vapor pressure could benefit the entire car 

park from day one. In the NPRM, EPA notes that “attention is needed to insure better in-use 
Tier 3 Summary and Analysis of Comments

4-321

performance of current evaporative emissions.” A reduction in market fuel summertime vapor 

pressure would reduce the evaporative emissions of in-use vehicles and address EPA’s concern. 

Tier 3 Summertime Market Gasoline RVP Cap should be 8 psi (9 psi for E10): The most 

effective method of controlling prospective evaporative emissions in conventional gasoline use 

areas would be to move promptly to lower the maximum allowable RVP to compensate for the 1 

psi waiver, perhaps to 8 psi. When the statutory mandate for the 1 psi ethanol waiver is added, 

the fuel would then become 9 psi, as it was before the introduction of ethanol. Similar to EPA’s 

proposed market sulfur standard, this would bring about an immediate reduction in summer 

light-duty evaporative emissions without waiting for the fleet to turn over. In addition, there 

would be evaporative emissions reductions from all gasoline powered equipment, further 

enhancing the benefits of this approach. 

10 psi RVP gasoline hinders states seeking to avoid backsliding out of attainment, or 

neighboring states trying to meet State Implementation Plans (SIPS) to reduce criteria pollutant 

emissions. 

9 psi RVP Market and Test Fuel is Important to Avoid Emission Backsliding: EPA and the U.S. 

Congress are concerned about the air quality impacts of the higher RVP E10 blends that have 

swept across large portions of the nation. Under the Energy Policy Act of 2005, EPA is 

mandated to undertake a “backsliding analysis” consisting of the following components: draft 

analysis, final analysis, emissions model, and a permeation effects study including evaporative 

emissions. Not content with the direction contained within the 2005 Energy Policy Act, 

Congress, within the Energy Independence and Security Act of 2007, wrote a section, 209, 

entitled “anti-backsliding”. In this section, Congress again directed that “the Administrator shall 

complete a study to determine whether the renewable fuel volumes required by this section will 

adversely impact air quality as a result of changes in vehicle and engine emissions of air 

pollutants regulated under this Act.” Further, Congress directed that “Not later than 3 years after 

the date of enactment of this subsection, the Administrator shall— ‘(A) promulgate fuel 

regulations to implement appropriate measures to mitigate, to the greatest extent achievable, 

considering the results of the study under paragraph (1), any adverse impacts on air quality, as 

the result of the renewable volumes required by this section; or (B) make a determination that no 

such measures are necessary.’’’

EPA has a congressionally mandated duty to complete the anti-backsliding study and to 

promulgate fuel regulations to implement appropriate mitigation measures based upon that study. 

It is in that mitigation rulemaking that EPA should determine the appropriate RVP of gasoline 

(certification and market gasoline). To regulate certification fuel RVP in this Tier 3 rule puts the 

cart before the horse. Moreover, EPA is trying to fix a problem it sees with in-use gasoline RVP 

that Congress has instructed EPA to study and fix with fuel regulations under its RFS authority. 

GM does not believe that increasing certification fuel stringency for an evaporative emissions 

test that will phase in over the next seven years qualifies as “to the greatest extent achievable.” 

EPA must pursue the appropriate mitigation measures through a separate rulemaking that is 

informed by the results of its study. 

Organization: National Automobile Dealers Association (NADA)
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EPA should adopt a nationwide Tier 3 summertime market RVP cap of 8 psi for E0 and 9 psi for 

E10. In addition to enabling Tier 3 compliance, doing so result in evaporative emission reduction 

benefits for the in-use fleet. 

Organization: Ford Motor Company (Ford)

Market Fuel Vapor Pressure Must be Controlled Based on Seasonal Ambient

Temperatures: Vapor pressure is the most important property for engine start-up performance. At 

higher ambient temperatures, the fuel can vaporize prematurely prior to reaching the injectors, 

disrupting the fuel flow to the engine and creating “vapor lock”. As defined in ASTM D4814, 

vapor lock conditions arise “if too much vapor is formed, the fuel flow to the engine can be 

decreased, resulting in loss of power, rough engine operation, or engine stoppage.” During cold 

ambient temperatures, fuels with vapor pressures that are too low can prevent the engine from 

starting at all or have poor warm-up performance. Thus, the vapor pressure and distillation 

profile of gasoline must be controlled based on seasonal ambient temperatures so that fuel 

vaporizes easily (higher vapor pressure) in cold weather to assist in engine starting and vaporizes 

less easily (lower vapor pressure) in warm weather so as to prevent vapor lock and reduce 

evaporative emissions. Evaporative emissions of hydrocarbons from the fuel system can occur 

not only during vehicle operation, but while the vehicle is at rest during periods of increasing 

ambient temperatures. Numerous studies have shown that the vapor pressure has a profound 

effect on the amount of hydrocarbon evaporative emissions. 

Recommendation: Ford supports the reduction in market fuel vapor pressure as detailed in the 

Alliance comments. Ford supports an ambient temperature (seasonally) appropriate 8 psi (9 psi 

for E10 due to the 1psi waiver) vapor pressure maximum for market fuels. Likewise, Ford also 

supports a 9 psi maximum Tier 3 certification fuel. 

Organization: POET, LLC

RVP limits must not be a barrier to the use of higher ethanol blends. RVP is a measure of 

gasoline volatility that EPA regulates to address summer ozone (smog) issues. Under the 

statutory framework, CAA Section 211(h) mandates that EPA shall limit introducing ‘into 

commerce gasoline with a Reid Vapor Pressure in excess of 9.0 pounds per square inch (psi)’

and further limit RVP in certain nonattainment areas. 

Notably, the RVP provisions in CAA Section 211(h) only control ‘gasoline.’ Because E10 and 

E15 have been considered part of the gasoline family, these ethanol blends have been regulated 

by these provisions. However, ethanol alone doesn’t cause RVP issues, because ethanol itself has 

very low vapor pressure. Furthermore, EPA notes that as ‘the ethanol level increases, the 

volatility increase caused by blending ethanol with gasoline begins to decline.’

Because ethanol blended with gasoline to make E10 can have a RVP slightly above the 

regulatory limit, CAA Section 211(h)(4) provides a 1 psi RVP ‘ethanol waiver.’ In particular, 

section 211(h)(4) specifies that ‘For fuel blends containing gasoline and 10 percent denatured 

anhydrous ethanol, the Reid vapor pressure limitation under this subsection shall be one pound 

per square inch (psi) greater than the applicable Reid vapor pressure limitations.’
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Although ethanol blends greater than 10% generally have lower RVP than E10, such blends may 

nonetheless be slightly over the regulatory limit and thus merit the use of the 1 psi waiver. These 

ethanol blends over 10% are critical to ensure that the RFS standards are met, and they provide a 

host of environmental and energy-security benefits. It would be the height of poor policy design 

by EPA to bar cleaner fuels that nonetheless may slightly tick over an RVP threshold when a 

waiver is given to fuels with a higher RVP. 

If RVP issues are not otherwise addressed, then the current 1 psi waiver should be applied to all 

ethanol blends over E10 (i.e., E11 and above). 

Alternatively, the above statutory provisions in CAA Section 211(h)(4) granting the 1 psi waiver 

to ethanol blends should be read as only requiring a minimum 10% ethanol content. EPA 

wrongly rejected this approach whereby the ‘10 percent’ threshold should be construed as 

requiring ‘at least’ 10 percent ethanol. EPA reached this approach by indicating that its 

interpretation ‘harmonizes’ sections 211(h)(4) and 211(h)(5). Section 211(h)(5) requires EPA to 

not apply the 1 psi waiver on petition by the Governor of a State that the waiver will ‘increase 

emissions that contribute to air pollution in any area in the State.’

However, EPA’s bar on extending the E10 waiver to E15 is not compelled by the statutory 

language. EPA ignores that in subsections 211(h)(4) and 211(h)(5) the references to ‘fuel blends 

containing gasoline and 10 percent’ ethanol used in both can (and should) be interpreted to mean 

gasoline fuel blends containing at least 10% ethanol. Additionally, the statute here references 

‘blends’ in the plural, suggesting that an EPA interpretation focusing only on E10, while 

ignoring other blends with at least 10% ethanol, is improper. 

Furthermore, EPA’s bar on extending the E10 waiver to E15 is inconsistent with prior 

rulemakings, and Congress’ understanding of these prior rulemakings. Congress based the 1 psi 

waiver in section 211(h)(4), in part, on EPA’s 1987 rulemaking that established national 

volatility limits for gasoline but expressly allowed E10 to exceed the general RVP limits by 1 

psi. In EPA’s 1987 rulemaking, EPA established a minimum ethanol content ‘to assure that fuel 

containing only trace amounts of alcohol does not qualify’ for the waiver. Furthermore, EPA’s 1 

psi waiver prior to the 1991 amendments expressly applied to fuels containing ‘at least 9% 

ethanol.’

Additionally, EPA’s current approach is inconsistent with legislative history in enacting 

211(h)(4). In particular, Section 216 of House Bill 3030 (1990), which eventually merged with 

Senate Bill 1630 to amend the CAA, made clear the 1 psi waiver was applicable to ‘gasoline 

containing at least 10 percent ethanol.’

Additionally, EPA’s current approach bars the use of an environmentally preferable fuel (E15), 

because its improved RVP still merits use of the 1 psi waiver, which is illogical. 

Furthermore, EPA glosses over the fact that 211(h)(5) was enacted as part of the Energy Policy 

Act of 2005 whereby Congress set RFS targets that would mandate the greater use of ethanol 

blends. EPA’s barring the extension of the 1 psi waiver (1) conflicts with precedent, and (2) 

frustrates the flexibility to use different ethanol blends to meet RFS targets enacted in the same 
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EPAct 2005 legislation, and should be reversed. And EPA can do so by simply changing its 

statutory interpretation. 

Additionally, subsequent to EPA’s 2011 misguided interpretation, blend wall concerns that have 

arisen placing a premium on EPA allowing the increased distribution of E15 into commerce. 

Quite simply, EPA should change its interpretation and allow extension of the 1 psi waiver to 

blends that contain at least 10% ethanol, as the statute allows. By doing so, EPA would promote 

the distribution of E15 and MLEBs and help to ‘ensure’ that the mandated RFS volumes are met.

Organization: Renewable Fuels Association (RFA)

RFA believes EPA should provide equal RVP treatment for E10 and E15. EPA should be 

consistent in its treatment of RVP requirements for all ethanol blends up to 15% by volume. 

EPA’s initial decision to grant the 1 psi waiver to E10 blends was based on two fundamental 

findings: 1) that supplies of low-RVP gasoline blendstock for E10 blending were insufficient, 

and 2) that the increased volatility associated with the 1 psi waiver was more than offset by 

reduced carbon monoxide and exhaust hydrocarbon emissions from E10. Recent analyses have 

shown that the vapor pressure of E15 is lower than it is for E10. Further, there is evidence that 

E15 provides greater reductions in carbon monoxide and exhaust hydrocarbon emissions than 

E10. Currently there is insufficient low-RVP gasoline blendstock to accommodate E15 blending 

(i.e., without a 1 psi waiver). Thus, the same two findings that led EPA to issue the 1 psi waiver 

for E10 also apply to E15. As such, if the 1 psi waiver continues to apply to E10, there is no 

logical reason that it should not also be applied to E15. 

On the other hand EPA should consider eliminating the 1 psi waiver for E10 provided that RVP 

caps are administered consistently across all ethanol blend levels. That is, if EPA decides to 

discontinue the 1 psi waiver for E10, it should do so immediately so that E10 and E15 are being 

treated consistently in the marketplace with regard to RVP. This is a critical issue for the near 

term for E15 to expand in the marketplace. Discrepancies in the treatment of RVP limits for E10 

and E15 are impeding the introduction of E15. Consistent treatment of RVP requirements for 

ethanol blends up to E15 will reduce the potential for more “boutique fuels” and maximize 

flexibility for refiners and gasoline marketers. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

A national minimum octane number of 87 AKI without regard to altitude is needed as a Federal 

Tier 3 standard for regular gasoline 

A uniform, nationwide minimum octane grade of 87 AKI (Antiknock Index) is needed to support 

MY 2017 vehicle performance, fuel efficiency, and emission reductions. 85 AKI octane grade is 

no longer relevant for high altitude use, and lower octane can cause newer engines to perform 

poorly. For some time, all OEMS have designed and engineered vehicles to run on 87 AKI, and 

all recommend use of minimum 87 AKI for regular gasoline (without regard to altitude) in 

vehicle owner’s manuals. 
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Federal action is specifically needed to avoid a patchwork of State octane standards allowing for 

use of 85 octane grade gasoline, even in some locations that don’t qualify as high altitude, such 

as South Dakota where access to >85 AKI gasoline in the western part of the State became 

limited and problematic. EPA should prevent backsliding of octane levels in refinery BOB 

(blend stock for oxygenate blending) because it leads to sub-grade octane product, and in some 

areas also stimulates interest in use of metallic additives to boost octane, which are opposed by 

automakers (see below). 

The AKI (octane number of gasoline, also referred to as the octane grade or rating, is a measure 

of its antiknock performance, or resistance to engine knock (often called spark knock because it 

is affected by the spark timing of the engine, among other factors). It is based on an index taken 

from an average of two different test outcomes, the RON (Research Octane Number) and the 

MON (Motor Octane Number). The higher the AKI octane number, the greater the fuel’s 

resistance is to knock. Spark knock is an abnormal combustion event that creates an acoustic 

wave in the combustion chamber, causing a pinging sound. If the knock is severe enough, it can 

damage the engine. 

It is widely documented that a gasoline’s octane number rating and a vehicle’s performance are 

directly linked. 

The U.S. General Accounting Office (GAO) reported on the importance of consumers 

understanding the proper gasoline octane rating number to select for their vehicles. The GAO 

stated: “Consumers need to buy gasoline with an octane rating that matches their engines’ octane 

requirements. Buying gasoline with too little octane can cause engine knock, which can damage 

an engine, lower engine efficiency, reduce mileage, and increase emissions’.

Since the mid-1980s, U.S. vehicles have included computer controls to monitor combustion 

performance and mitigate auto-ignition (knock) by way of three mechanisms: retarding or 

delaying ignition timing, fuel enrichment to cool the in-cylinder end-gas environment, and, in the 

case of pressurized air induction equipped vehicles, reducing the level of boost or super-charging

in order to rapidly and momentarily reduce engine output. These mechanisms protect the engine 

from acute and potentially severe damage. However, they result in sub-optimal combustion, 

lower engine efficiency, and in the case of ignition timing delay, result in higher exhaust 

temperatures. Although the sophistication and speed of modern vehicle computer controls has 

increased greatly since the 1980s, these three primary mechanisms of knock control are still 

widely used. 

As vehicle manufacturers strive for increasingly efficient designs, the vehicle hardware and 

calibrations have been significantly upgraded, putting modern vehicles closer than ever to spark 

knock limited operation. For example, as a result of increased number of transmission gears, 

more frequent operation at lower engine speeds for a given vehicle speed puts the engine at a risk 

of low speed spark knock. Additionally, exhaust emission reduction catalysts are increasingly 

“close coupled” to the exhaust manifold to enable their early light-off and high oxidation 

efficiency; however, this makes them more susceptible to temperature spikes (thermal stresses) 

from auto-ignition events. And because vehicle sizes and therefore their masses remain relatively 

high while engine displacements are quickly dropping, the load factor under which an engine 
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operates is rapidly increasing. In total, today’s vehicles and their computer controls are 

constantly monitoring and optimizing to the available gasoline octane number in the vehicle’s 

fuel tank. 

The continued presence of 85 and 86 AKI octane grade gasoline, predominantly in the U.S.

Rocky Mountain States, is limiting vehicle efficiency and performance. 

U.S. automobiles have been designed for 87 AKI gasoline since the mid-1970’s, when the 

octane-enhancing organometallic additive tetra-ethyl lead was phased out. As a result of lead 

removal, the predominant gasoline octane number of Regular Unleaded was reduced from 91 / 

92 AKI to 87 AKI and engine compression ratios were reduced from 9.0 – 10.5: 1 to 7.5 – 8.5:1. 

By contrast, a review of 2012 Model U.S. Car and Light Truck Specifications and Prices from 

the Wards Auto group shows compression ratios have again risen substantially since the 1970’s 

to 10.5 – 11.5:1 for naturally aspirated engines, while the predominant U.S. Regular Unleaded 

gasoline octane rating remains at 87 AKI. [

Recent Vehicle Performance Testing using 85 AKI Gasoline [

NOTE: The information in this section of the comments is from an unpublished Alliance study; 

it is Alliance work product and protected under copyright. [

In early 2013, the Alliance completed the test portion of a study to measure the magnitude of 

performance effects of operating vehicles on lower octane rating gasoline than for which they 

were designed. For this study, two 2012 production vehicles were tested in the General Motors 

Milford Proving Grounds “variable altitude” emissions facilities during January and February, 

2013. The two vehicles are Regular Unleaded (87 AKI) calibrated vehicles and the tests were 

conducted using standard chassis dyno emissions test cycles at Sea Level (0 Ft). The emissions 

test cycles were chosen to be moderate to heavy customer driving, the LA92 and US06 cycles, 

respectively. During the emissions testing procedures, the vehicle’s speed was maintained within 

a precise window of operation by the trained driver by opening and closing the throttle (part 

throttle). 

The two octane ratings for the test fuels were 84.8 AKI and 87.8 AKI as reported on the fuel 

supplier’s Certificate of Analysis, and all other fuel composition properties were held very close 

to each other. Ideally, the AKI rating of the “87 AKI” fuel would have been closer to 87.0, but 

based on the very large differences in vehicle performance measured (as fuel economy and 

emissions), it is expected that this would have made only a marginal change in results. 

The vehicle performance data shown below [Table 4 can be found on p. 84 of Docket number 

EPA-HQ-OAR-2011-0135-4461-A1] is the percent difference in each parameter from operating 

the vehicles on 87 AKI gasoline compared to operating the vehicle on 85 AKI gasoline. The 

results for the two repeat US06 cycles were combined and then compared in an “A-B” (87 – 85) 

format. A vehicle data logger recorded the Engine Control Module (ECM) serial port 

information and no test drift is anticipated from these signals. While operating on the proper (i.e., 

owner’s manual specified) 87 AKI gasoline, the vehicles utilized less throttle, required less load 

on the engine, and less fuel enrichment, and where applicable, less boost pressure to maintain the 
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vehicle speed traces of the standardized emissions test cycles. [EPA-HQ-OAR-2011-0135-4461-

A1, pp. 83-84]

The vehicle emission and fuel economy effects can be seen below [Table 5 can be found on p. 85 

of Docket number EPA-HQ-OAR-2011-0135-4461-A1] and were analyzed in an “A-B-A” 

format (85-87-85) to account for any test drift from the catalyst response. Substantial 

improvements in fuel economy and emissions performance can be seen while operating on the 

proper 87 AKI gasoline during these controlled chassis dyno tests. 

Sales of 85 AKI gasoline represent less than 4 % by volume of the total U.S. gasoline 

production, but they have an impact on 100% of the vehicle fleet.

A recent study by the Coordinating Research Council (CRC) Performance Committee Octane 

Group has determined that it requires about 4 – 5 RON units to allow an increase of one (1) 

number in an engine’s compression ratio. Auto manufacturers must protect for the lowest octane 

in the market, because they cannot know in which U.S. State their vehicles will be sold and 

operated, so the presence of an 85 AKI gasoline represents about 0.4 – 0.5 compression ratio of 

inefficiency yet to be utilized. This is not to say that powertrain compression ratios would rise by 

0.4 -0.5 units if the U.S. had a national 87 AKI minimum limit, but rather there is an equivalent 

amount of efficiency gain still unrealized either in terms of higher compression ratios, less fuel 

enrichment, more optimal combustion phasing, or higher boost. Additionally, if 87 AKI was the 

national minimum market fuel standard, vehicles already on the road would operate a greater 

percentage of time without fuel enrichment. 

Prompt federal action is needed under Tier 3, to avoid a patchwork of State octane standards and 

proliferation of use of 85 AKI gasoline.

Currently, the most widely referenced gasoline specification in the U.S. is ASTM’s D4814, 

“Standard Specification for Automotive Spark-Ignition Engine Fuel.” ASTM does not specify 

mandatory octane minimum limits. Determination of the proper octane number to be sold in the 

marketplace is left to the discretion of the fuel marketers. Likewise, the NIST Handbook 130 

(Laws and Regulations) does specify the proper octane number naming convention at retail, but 

does not specify the actual octane number minimums. Because of this uncertainty, some States 

have adopted D4814, some have adopted Handbook 130, and some have written their own 

specification. For example, South Dakota currently has a “hybridized” octane standard. 

Historically, 87 AKI has been sold throughout the U.S. as Regular Unleaded except in Rocky 

Mountain States where a mix of 85 and 86 AKI is sold. Also, recently it has been reported that in 

certain regions of the country with an excess of hydrocarbons resulting from new fracking 

techniques, it has become profitable to truck in 85 and 86 AKI gasoline to lower elevation 

regions of the country. This is going backwards in terms of emissions, engine efficiency, and real 

fuel economy, for highly localized refinery and retail savings.

Furthermore, in the event that EPA does not set a national minimum 87 AKI octane market 

gasoline standard, gasoline with octane lower than that of federal emission test fuel is not 

“substantially similar” to the certification test fuel. By closely regulating the octane of emission 

test fuel, EPA has signaled that this is a critical fuel parameter. Under CAA §211(f) all gasoline 
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must be “substantially similar” to fuels used for certification. Such fuel should not be allowed to 

remain in the market place since new vehicles will be certified to a higher octane fuel (unless 

fuel producers can demonstrate such fuels will not cause or contribute to the failure of any 

vehicle/engine to meet emission standards, subject to notice and comment). 

In support of Tier 3 and other vehicle needs, EPA should promptly set a federal minimum 

standard mandating 87 AKI as the minimum octane grade for regular gasoline, without regard to 

altitude. 

Organization: Ford Motor Company (Ford)

Elimination of Sub-Regular (<87 AKI) Octane Grades: As stated above, the use of fuel with 

higher octane ratings will allow improved performance (increased efficiency) for newer vehicles 

with certain advanced technologies. However, the use of fuel with an antiknock or octane rating 

lower than the required amount may result in vehicle performance loss or engine damage. 

Engines equipped with knock sensors will compensate for the reduced octane rating by retarding 

spark timing, but this can result in increased fuel consumption and reduced power and may not 

completely prevent the engine from knocking. Although altitude and weather have been shown 

to affect a vehicle’s antiknock requirement for most pre-1984 vehicles, modern vehicles in 

today’s fleet require the same antiknock index as stated in their owner’s manual, regardless of 

ambient temperature or altitude. Despite this requirement, several western states with higher 

altitude areas in the U.S. continue to offer 85 AKI instead of 87 AKI for their “regular grade” 

market fuels, with the potential for expanded availability. This availability and any further spread 

of sub-regular grade market octane rating fuels amounts to “back-sliding” in market fuel quality 

and subsequently emissions inventory. This is in direct conflict with the agenda outlined in both 

the Tier 3 rules and the ONP rules, which will require increased fuel economy in tandem with 

decreased CO2 emissions. In order to meet the increasingly stringent requirements of the ONP, 

manufacturers will continue to implement a host of new technologies (cylinder deactivation, 

hybridization, continuously variable transmission, 9-speed transmissions, Atkinson engines, 

downsized turbocharged direct injection engines) that will require a commensurate increase in 

market fuel quality and market fuel octane ratings. EPA must recognize that gasoline octane has 

become a critical factor in the development and sale of vehicles with newer advanced 

technologies, and this issue needs to be addressed on a nationwide basis. As noted above, the 

typical octane rating of U.S. marketplace fuel needs to increase, and the sale of gasoline with 

sub-regular octane (less than 87AKI) needs to be eliminated nationwide. 

Recommendation: Ford supports the Alliance comments calling for a national minimum octane 

number of 87 AKI for regular grade gasoline, without regard to altitude. 

Organization: Mercedes-Benz USA, LLC on behalf of Daimler AG

The primary factors which directly impact the Mercedes-Benz GHG Compliance Plan are sulfur 

content in market fuel, and ethanol content and octane level in certification and market fuel. 

Organization: International Council on Clean Transportation (ICCT)
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What is really needed is higher octane for regular fuel, regardless of the ethanol content. For 

example, the Mazda had to reduce the compression ratio of the Skyactiv engine for the US 

market, compared with Europe. Also OEMs simply won’t try to sell a mass-market non-luxury 

vehicle that requires mid- or high-grade gasoline in the US. 

Unfortunately, when fuel providers added ethanol to gasoline in the past, the fuel providers took 

out the non-ethanol octane elements - so that, in practice, there has never been a gain in octane 

through increased ethanol blends. It is likely that E15 will be the same—we won’t actually get 

more octane. Rather than focus on ethanol requirements, the EPA should raise the minimum 

octane requirements for all gasoline. 

Organization: General Motors LLC (GM)

Gasoline Octane is Important for Emissions – Certification and Market Fuels: 

Octane rating of both marketplace gasoline and Tier 3 certification fuels is critical to vehicle 

performance, including their exhaust emissions. For this reason, GM specifies the octane 

requirement of every vehicle in the vehicle owner’s manual. GM fully supports the 

Alliance/Global comments on octane. 

Organization: National Marine Manufacturers Association (NMMA)

For the past three years, NMMA has been working with the US Department of Energy and 

Argonne National Laboratory to evaluate a better alternative to ethanol, both as an oxygenate 

and a biofuel. Our research and testing of isobutanol is a result of the problems associated with 

increased levels of ethanol being used as a fuel additive. Our research findings include: 

- Ethanol raises the Reid Vapor Pressure of gasoline, which at higher levels increases 

evaporative emissions. Meeting US EPA and CARB RVP standards for ethanol blends therefore 

requires refineries to perform additional processing. 

- Ethanol is corrosive and is typically shipped via railcar or truck versus less expensive pipelines. 

- Ethanol is splash blended at the end of the gasoline refining process, adding additional storage 

and labor cost. 

- Ethanol is hygroscopic, meaning it has an affinity for water. 

- Ethanol at 10% by volume contains approximately 2.5% oxygen. Increasing ethanol content in 

gasoline increases the oxygen level (referred to as enleanment) causing open loop engines to 

experience increased combustion temperatures. 

Rather than simply oppose all ethanol and biofuels, NMMA has dedicated considerable 

resources over the past three years to evaluate isobutanol in order to contribute meaningful data 

to steer future biofuels policy and ensure compatibility with millions of non-road engines and 

boats. 

Recreational marine engines and vessels represent a worst-case environment in which to validate 

the reliability and compatibility of advanced biofuels such as isobutanol due in part to the usage 

cycles of marine products, open-vented fuel systems, likelihood of introducing saltwater into fuel 

systems and open-loop engine operation. Successful demonstration of isobutanol-extended 

gasoline in the marine environment may ensure that engine emissions, engine and vessel 
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performance, engine durability and product safety (fuel system related) could be maintained for 

millions of small engines including recreational marine engines and vessels. Moreover, 

successful testing in a worst-case marine environment will allow for a more streamlined 

acceptance of advanced biofuels outside of on-road vehicles, potentially minimizing the effects 

of the current bifurcated fuel system. 

NMMA has conducted tests on a variety of marine engines and vessels using 16% isobutanol by 

volume, which has similar oxygen content to E10, without the other negative properties of 

ethanol identified above. The results of our documented and published research thus far indicate 

that isobutanol at 16% by volume yields very similar engine emissions, durability, power and 

performance as E10. 

This summer, NMMA is conducting tests with Argonne National Laboratory under the direction 

of the U.S. Department of Energy on a tri-fuel blend of 5% ethanol, 8% isobutanol and 87% 

gasoline to determine the effects on emissions, performance and overall fuel compatibility with 

recreational marine engines and vessels. Our preliminary analysis has shown that isobutanol acts 

to lower Reid Vapor Pressure, while also increasing the overall biofuel quantity in gasoline. 

NMMA strongly urges EPA and DOE to take a leadership role in appealing to Congress and the 

President to freeze ethanol at 10%, while neutral party technical evaluation are conducted to 

assess alternatives that can be introduced at a higher concentration without the negative effects of 

ethanol.

Commenter: Refinery Automation Institute, LLC

The EPA proposal lacks transparency and seems politically motivated, in that uses words to 

describe ‘implied’ changes in Aromatics, Olefins, Vapor Pressure, and Distillation temperatures. 

This promotes ‘back-door’ regulations by ‘selling’ and unambiguously implying ‘harmonization’ 

with California’s CARB RFG3 specs (Attachment II). The impact on costs is misleading in 

EPA’s Tier 3 proposal.

Our Response:

Some commenters suggested that the 1-psi RVP waiver be extended to all ethanol blend 

levels, or be eliminated altogether, either of which would create a more level playing field for 

higher ethanol blend s in the market. Some commenters expressed support for raising the 

minimum octane of in-use gasoline, or for limiting ethanol content and/or encouraging the use of 

other oxygenates (e.g., isobutanol). EPA is using its Clean Air Act section 206 authority to 

establish requirements for emission certification testing, including specifications of the emissions 

test fuels with which vehicles demonstrate compliance with emissions standards, in order to 

better reflect the ethanol content and other properties of in-use fuels. While we are taking action 

to limit the sulfur content of in-use gasoline under authority in Clean Air Act sections 211(c)(1) 

and (2), we did not propose other changes to in-use fuels. Any action related to other changes to 

in-use fuels is outside the scope of this rulemaking.
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Some commenters supported revoking the 1-psi waiver on the basis that large reductions 

in evaporative emissions would be expected in the in-use fleet, and that EPA should use 

authority given under Clean Air Act section 211(v) to accomplish this. The requirements of that 

section include completion of the anti-backsliding study, which is still underway. Once the study 

finalized, EPA will assess what, if any, regulatory action is warranted.

One commenter expressed concern regarding implied changes in fuel properties and 

harmonization with California. The commenter appears to be confusing EPA’s actions to adjust 

the properties of certification test fuel with potential changes to in-use fuel. The Tier 3 

rulemaking is only requiring changes to the sulfur level of in-use gasoline.

4.5.2. Proposed Flexible Fuel Vehicle Test Fuel

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Automakers agree with EPA that it is important that the fuel used to test FFVs reflect the 

composition of actual in-use E85 (30). ASTM has revised specification standard, ASTM D5798-

The most significant driver for the recent revisions to the ASTM E51-83 specifications has been 

the inability of terminals to blend E85 that met the requirements of the E85 specification using 

current gasoline and BOBs (Blend-stocks for Oxygenate Blending). After significant study, the 

ASTM task group decreased the minimum allowable ethanol percentage to 51% as the best way 

to enable E51-83 blends with compliant RVPs (Reid Vapor Pressure). 

There is currently little data available on actual E51-83 fuel composition in the field. Previous 

studies on E68-83 showed that much of the field fuel did not meet the ASTM requirements. 

These results drove the re-evaluation and revision of the specification mentioned above. Later 

this year, the National Renewable Energy Lab, in conjunction with the Coordinating Research 

Council, will survey field E51-83 quality. This is the first survey since the revisions were 

implemented to ASTM specification D-5798: Ethanol Fuel Blends for Flexible-Fuel Automotive 

Spark Ignition Engines. EPA should wait to finalize specifications until it can take into 

consideration the results of the NREL-CRC survey when they become available. 

EPA should implement our recommended specifications for E85, CNG and LPG detailed above. 

Organization: American Lung Association

For Flexible Fueled Vehicles (FFV) test fuel, we support an approach that includes the standard 

certification fuel, E10 until such time as EPA revises to E15 if market conditions warrant, as 

discussed above, with additional denatured fuel ethanol to meet the 80-83 volume percent. 

Organization: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)
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API and AFPM support EPA’s proposed approach for FFV test fuel. With regards to the 

Flexible Fuel Vehicle Test Fuel, we agree with EPA’s proposal to make the fuel by blending the 

gasoline emission test fuel base stock with higher levels of ethanol to produce the test fuel and 

trim the resulting fuel with normal butane to achieve the necessary vapor pressure. 

Organization: General Motors LLC (GM)

GM fully supports the Alliance/Global comments on both E85 and CNG/LPG certification fuels.

Organization: Growth Energy

Growth Energy Supports a Workable Flex Fuel Vehicle (FFV) Certification Fuel: EPA also 

proposed a specific “E85” test fuel with an ethanol concentration of E80-E83 that would be 

made by blending ethanol (either denatured fuel ethanol or neat ethanol) with the E15 test fuel. 

Growth Energy continues to believe that Flexible Fuel vehicles will be essential to use the higher 

ethanol blends needed to meet the future volumes of the RFS. As such, it only makes sense to 

develop a specific test fuel for FFVs. However, we do not think that the specifications are

representative of E85 found in marketplace, especially since ASTM has published its “Flexible 

Fuel” specification. 

Growth Energy would suggest that the RVP of the FFV certification fuel should be at 9 psi and 

the ethanol content should be somewhere in the range of 70-78 percent (E70 – E78). 

Organization: Marathon Petroleum Company LP (MPC)

With regards to the Flexible Fuel Vehicle Test Fuel, we agree with EPA’s proposal to make the 

fuel by blending the gasoline emission test fuel base stock with higher levels of ethanol to 

produce the test fuel and trim the resulting fuel with normal butane to achieve the necessary 

vapor pressure. 

Organization: National Association of Convenience Stores (NACS) and Society of 

Independent Gasoline Marketers of America (SIGMA)

The Proposal would make E80-83 the default test fuel for FFVs. While it necessary to develop 

regulatory specifications for E85 test fuel blends, the Proposed Rule does not account for the fact 

that certain jurisdictions contain caps on ethanol content in E85 below 80 percent. The final rule 

should accommodate fuels that will actually be in the market. 

NACS and SIGMA applaud the Agency for developing regulatory specifications for E85 test 

fuel blends. The lack of specifications up to this point has caused confusion and inconsistency in 

the market. There is concern, however, that the proposed specifications of 80-83 volume percent 

does not accommodate fuels that will actually be in the market. Indeed, ASTM specifications for 

E85 include a fuel containing between 51 – 83 volume percent ethanol5. In addition, different 

jurisdictions in the country contain various restrictions on ethanol content for E85 fuels. Some of 
Tier 3 Summary and Analysis of Comments

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these jurisdictions contain caps below 80 volume percent ethanol. As a practical matter, this 

means the Agency is proposing default test fuel that simply will not be utilized in these areas.

It is important that the final rule accommodates fuels that will actually be in the market. The 

revised ASTM definition for E85 enhances marketers’ ability to provide consumers with a fuel 

product that might be offered at a more attractive price and provide greater fuel efficiency than is 

currently being experienced with blends containing 80-83 volume percent. This flexibility 

should be encouraged. NACS and SIGMA would be happy to work with the Agency to develop 

a policy for accomplishing this objective in the final rule. 

Organization: National Corn Growers Association (NCGA)

And, while we are generally supportive of establishing new certification fuel requirements for 

FFVs, we are concerned that the proposed approach would inhibit future development of FFVs 

and the development of dedicated vehicles designed for the exclusive use of an high octane 

MLEB. Both FFVs and high octane utilizing vehicles are critical to ensuring that the 150 million 

metric tons of GHG emission reductions from the RFS volumes are attained. 

We support the development of specifications for FFV certification test fuel. As the RFS 

requirements ramp up beginning in 2015 and later, we believe the incentive will increase to 

produce more ethanol-containing fuels, and that E85 use in FFVs is likely to increase. Now that 

ASTM has published and refined its ASTM 5798 “Flex Fuel” specification, it is reasonable to 

provide a more complete and comprehensive specification for the FFV certification test fuel. 

EPA proposed the E85 ethanol test fuel concentration be limited to E80-E83 and that this could 

be achieved by blending ethanol into E15 test fuel utilizing denatured fuel ethanol or neat 

ethanol. EPA also indicated that the vapor pressure of the test fuel should be between 6.0 and 6.5 

psi. However, we are concerned that EPA’s specification of E85, at E80-E83 with a vapor 

pressure of 6.0 to 6.5 psi, could inhibit the development of FFVs meeting the lowest 

NMOG+NOx standard bins of the Tier 3 proposed rule. 

We recommend that EPA consider the unique challenges and additional costs of designing FFVs 

to comply with Tier 3 Bin 20, 30 and 50 standards, and not create FFV test fuel specifications 

that unnecessarily increase the stringency of the emission standards and discourage production of 

FFVs. We are aware that the U.S. Department of Energy National Renewable Energy Laboratory 

and the Coordinating Research Council are beginning another field survey of E85 to compare the 

fuel quality to the most recent ASTM D5798-13 specification (16). We recommend that EPA use 

information from this survey to select specifications for FFV test fuel from the data rather than 

selecting a specification such as E80-83. 

16 - CRC Project no. E-85-3, “E-85/E-85-2/E-85-3 National Surveys of E85/Flex Fuel Quality”, project 

description available at http://www.crcao.org/news/Mid%20Level%20Ethanol%20program/E-85-

3%20Summary.pdf.

Organization: New York State Department of Environmental Conservation
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Higher level ethanol blend fuels for use in Flexible-Fuel Vehicles need to be subject to sufficient 

regulation to ensure proper function of vehicle emission control systems. 

Current regulation of fuels (other than gasoline) for use in Flexible-Fuel Vehicles (FFVs) is 

inadequate. As EPA staff note in a memo to the docket for this rulemaking (2) the commercial 

fuel must be substantially similar to a heretofore unspecified certification fuel... 

We agree with EPA’s decision to promulgate standards for FFV test fuel, and believe that such 

standards are overdue. 

2 - Memo from Jeff Herzog, Assessment and Standards Division, to Docket EPA-HQ-OAR-2011-0135, 

dated April 8, 2013 (docket item number EPA-HQ-OAR-0135-0529).

Organization: POET, LLC

Similarly important is the increased use in FFVs of fuel blends that contain from 51-85% ethanol 

(referred to in these comments as high-level ethanol blends or HLEBs). 

Regarding an HLEB certification fuel, EPA proposes that the certification fuel ethanol content 

must be from 80 to 83 volume percent.’ (62) Under Clean Air Act Section 206, test fuels should 

reflect ‘actual current driving conditions under which motor vehicles are used.’ EPA should base 

an HLEB certification test fuel that is more likely to be representative of HLEBs on which FFVs 

are likely to run. (63) POET suggests that an appropriate FFV/HLEB certification fuel is likely to 

have a % ethanol content in the 70s. 

Otherwise, POET supports the Proposed Rule discussion of HLEB certification fuel logistics 

with regard to how the test fuel is prepared for a particular blend level. In particular, EPA notes 

that ‘Rather than specify ranges for the other fuel parameters as we have done for gasoline test 

fuel ... we are proposing that the FFV test fuel would be defined based on the results from 

blending the proposed E15 standard gasoline test fuel with ethanol.’ (64) The Proposed Rule 

would also allow the use of butane to trim RVP. In the alternative, BOB and undenatured ethanol 

could be used to prepare the test fuel. (65) POET approves of this approach. 

62 - Id. at 29,912.

63 - By comparison, 40 CFR 86.113-94(d) provides specifications for methanol fuels for flexible fuel 

vehicles and states ‘Mixtures of petroleum and methanol fuels used for exhaust and evaporative emission 

testing and service accumulation for flexible fuel vehicles shall consist of the appropriate petroleum fuels 

... and a methanol fuel representative of the fuel expected to be found in use ... and shall be within the 

range of fuel mixtures for which the vehicle was designed.’ (emphasis added). By the same logic, the 

ethanol fuel family could have two certification fuels, and those certification fuels need only be 

representative of the range of ethanol blends ‘within a range’ of mixtures ‘expected to be found in use.’

64 - Id. at 29,912.

65 - Id.

Organization: Renewable Fuels Association (RFA)

EPA’s proposed certification fuel for flexible fuel vehicles may discourage FFV production due 

to potential difficulty in meeting NMOG+NOx standard bin levels. 
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Our Response:

As discussed in Section IV.F.3 of the preamble to the final rule, EPA is finalizing 

specifications for the fuel used in flexible fuel vehicles (FFV) emissions testing including 

certification testing (see Section IV.F.3. of the preamble to the Tier 3 final rule). Establishing 

these specifications for FFV test fuel will resolve confusion and inconsistency among FFV 

manufacturers in carrying out their certification and other testing requirements and help to ensure 

that FFV emissions are appropriately controlled over the range of in-use fuels.

The base fuel stock used to formulate FFV emissions test fuel must comply with the 

specifications for the standard E10 emissions test fuel as described in Sections IV.F.1 and IV.F.2 

of the preamble to the Tier 3 final rule. This practice avoids the need to specify the ranges for a 

number of fuel parameters as we have done for gasoline test fuel and helps to minimize the 

number of test fuels that a vehicle manufacturer must store. Denatured fuel ethanol (DFE) that 

meets the specifications in the Tier 3 final rule must be blended into this base fuel stock to attain 

an ethanol content of 80 to 83 volume percent in the finished test fuel. Commercial grade 

normal butane can be added as a volatility trimmer to meet a 6.0 to 6.5 psi RVP specification for 

the finished test fuel.34

As an alternative to the use of DFE to formulate FFV test fuel, neat (undenatured) fuel 

grade ethanol can be used. As an alternative to using a finished E10 standard gasoline test fuel 

to produce FFV test fuel, the gasoline blendstock used by the fuel provider to produce a 

compliant E10 test fuel can also be used to produce the FFV test fuel. This would allow ethanol 

to be blended only once to produce FFV test fuel. In such cases, a sample of the subject gasoline 

blendstock must be tested after the addition of ethanol to produce a finished standard E10 

gasoline test fuel to demonstrate that the blend meets all of the requirements for standard 

gasoline test fuel. 

Substantial publicly available literature exists to demonstrate that the ethanol content of 

fuel used in FFVs has a significant effect on vehicle emissions. The effect of ethanol content on 

FFV emissions becomes more pronounced with increasing ethanol concentration. The current 

ASTM specification for E85 provides that the ethanol content of E85 may vary from 51 to 83 

volume percent depending on climactic conditions. 35 Consistent with our long standing policy 

regarding the emissions testing of FFVs, FFVs must comply with all applicable emissions 

control requirements for each consumed fuel or blend of fuel. This policy ensures vehicles are 

designed and calibrated for emissions performance across the full range of potential in-use fuel 

formulations. To ensure that FFV certification testing adequately accounts for in-use emissions 

performance, we are finalizing the ethanol content of FFV emissions test fuel at 81-83 volume 

percent as proposed. Exhaust emissions testing conducted using a fuel containing 81-83 volume 

percent ethanol will provide results that represent the effect of ethanol on FFV emissions 

performance when this effect is most pronounced. The complimentary emissions certification 

testing for FFVs on E10 will ensure that the effect on FFV emissions from the full range of 

potential in-use ethanol concentrations is represented. Although certain local jurisdictions may 

 

34 The specifications for commercial grade butane are contained in 40 CFR 80.82.

35 ASTM International D5798-13, “Standard Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive 

Spark-Ignition Engines”. 
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limit the ethanol content of FFV fuel to below the maximum 83 volume prevent set by ASTM, 

EPA must set test fuel specifications to ensure adequate emissions control performance 

throughout the U.S., including areas that do not have such additional limitations. Given the need 

to ensure that FFV emissions certification testing is representative of the full range of potential 

in-use ethanol blends, it would be inappropriate to set the required ethanol concentration for FFV 

emissions test fuel based on typical in-use levels as suggested by some of the commenters. 

Similarly, we are setting the RVP of FFV emissions test fuel to assure emissions 

performance over the range of in-use fuels. When ethanol and gasoline are blended to produce 

high level ethanol blends, the RVP can be and often is very low. As a result, ASTM included a 

minimum RVP for E51-83 of 5.5 psi. Given that low volatility fuels can make the control of 

cold start emissions more challenging, we are finalizing the RVP of FFV emissions test to be 

near the minimum RVP that will be encountered in-use. The 6.0 to 6.5 RVP specification will 

help to ensure that FFVs are designed and calibrated to maintain their exhaust emissions 

performance across the range of in-use fuels. A 9 RVP specification of FFV emissions test fuel, 

as suggested by some commenters, would not provide assurance of exhaust emissions 

performance with lower RVP fuels that are present in-use. We are also finalizing separate RVP 

specifications for the test fuel used for FFV evaporative and refueling emissions testing as 

discussed in Sections IV.C. and IV.F. of the Tier 3 final rule preamble.

The levels of other fuel parameters for FFV test fuel are determined by the levels of these 

parameters present in the gasoline blendstock used as diluted by the addition of ethanol.36 

Therefore, we believe that requiring that the levels of these other fuel parameters present in FFV 

emissions test fuel be determined by the dilution of the levels present in gasoline emissions test 

fuel appropriately reflects their potential effect on emissions performance. Given the 

considerations discussed above in determining the FFV emissions test fuel specifications, we do 

not believe that there would be a substantial benefit in waiting for the completion of the E51-83 

fuel quality survey currently underway to finalize FFV test fuel specifications.

As discussed in Section V.H. of the Tier 3 final rule, although we sought comment on inuse standards for E51-83 fuel for use in FFVs, we are not finalizing such standards at this time. 

To the extent future implementation of in-use fuel standards for E51-83 might impact in-use 

E51-83 quality, we may revisit the need to amend the FFV test fuel specifications finalized in the 

Tier 3 FRM.

With respect to the comment on the development of vehicles that are designed to operate 

on high octane fuels, mid-level ethanol blend fuels, EPA allows manufacturers to request 

approval certify on alternative certification fuels. Responses to comments on this topic are 

discussed in more detail in Chapter 4.5.1.5 of this Summary and Analysis of Comments 

document. 

 

36 Additional ethanol may either be added to the E10 emissions test fuel or to the gasoline blendstock used to 

formulate a compliant E10 emissions test fuel to meet the 80-83 volume percent ethanol specification that we are 

finalizing for FFV emissions test fuel.
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4.5.3. Implementation Schedule

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA/California Mutual Reciprocity Should be Made Permanent – to Assure The Automaker 

Option to Certify on Either the LEV III or the Tier 3 Test Fuel/Test Regime. EPA and California 

each should extend permanent reciprocity (mutual acceptance) of either LEV III test fuel/testing 

or Tier 3 test fuel/testing for purposes of both LEV III and Tier 3 certifications. EPA should not 

require use of Federal test fuel/test procedures after MY 2019 (28) for Tier 3 certification, as 

proposed. This is critical to facilitate OEM use of one fuel/one testing regime per vehicle model, 

a longstanding goal for harmonization between LEV III and Tier 3 standards toward One 

National Standard. The purpose of the arbitrary date cutoff in the proposal is not clear. 

For in-use compliance purposes, the same fuel (LEV III or Tier 3) selected for certification 

should also be used for in-use testing. 

Broadening future Federal Test Fuel options for OEMs should not negate reciprocity with 

California, or the option to use either LEV III test fuel/test regime or Tier 3 test fuel/tests for 

both California and Federal certification. 

(If no permanent reciprocity) EPA should accept carry-over certifications on LEV III 

certification gasoline beyond MY 2019 

ARB cannot amend the LEV III regulations until after EPA finalizes Tier 3. Thus, there will be a 

significant period (at least a year or two) of uncertainty where each agency has different 

certification gasoline requirements. 

The proposed Tier 3 regulations allow manufacturers to use LEV III certification gasoline only 

through the 2019 model year (MY). Beginning in the 2020 MY, all vehicles must be certified 

using Tier 3 certification gasoline and carryover of emissions data is not allowed. (See §86.113-

07, Fuel Specifications). If there is no permanent reciprocity, despite our strong support of that, 

then EPA should allow carryover of emissions data after 2019 MY. Manufacturers tend to

carryover emissions data for several years. 

Without an extension, this could result in manufacturers retesting and recertifying vehicles for no 

other reason than to change the certification gasoline. For example, a 2016 MY vehicle certified 

to LEV III standards on LEV III gasoline might be required to recertify on Tier 3 gasoline, rather 

than carry over the LEV III certification data through the 2020 or even 2021 MY until a redesign 

requires a new certification. This would be an unnecessary waste of resources and we do not 

believe this is EPA’s intent.

Consequently, we recommend that EPA allow carryover of certification data using LEV III 

gasoline through at least 2022. Assuming there is no reciprocity, new certifications beginning in 
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2020 could be required to certify on Tier 3 gasoline and Tier 3 evaporative emissions standards. 

This will provide sufficient time for ARB to amend its regulations to accept Tier 3 gasoline and 

test procedures. In the event ARB chose not to amend their regulations, EPA, ARB, and industry 

could develop an alternative that would prevent unnecessary testing.

There should be permanent reciprocity between California LEV III and Tier 3 so that automakers 

can test one time on one test fuel to certify for both LEV III and Tier 3, as originally envisioned 

toward One National Program. 

28 - 78 Fed. Reg. 29908 at 29869 (May 21, 2013).

Organization: California Air Resources Board (CARB)

Additionally, CARB recommends reciprocity with California’s gasoline certification fuel beyond 

2020 and throughout the lifetime of the Tier 3 program. CARB offers the following comments in 

support of our recommendation in an effort to further harmonize certification fuel program 

requirements of the two agencies. 

As proposed, Tier 3 provides reciprocity for certification fuel between the LEV III and Tier 3 

programs until model year 2020, at which time U.S. EPA will only recognize emission 

certification on federal certification fuel. Traditionally, the two agencies have granted reciprocity 

for certification fuel when demonstrating emission compliance, thus providing a degree of 

compliance flexibility to vehicle manufacturers without impacting the emission benefits of the 

California or federal programs. CARB believes this should continue to hold true whether Tier 3 

certification fuel is E15 as currently proposed or E10 (see our previous comment though on the 

impact of an RVP of 10 on reciprocity concerns for evaporative emission testing) and strongly 

recommends continuing the practice of providing reciprocity for certification fuel in the Tier 3 

program beyond 2020 and throughout the lifetime of the Tier 3 program.

Organization: Chrysler Group LLC

Chrysler supports EPA’s proposal to allow as an option certification using ARB test procedures, 

which include E10 fuel at 7.0 psi RVP, but believes that this option should be available 

permanently (past Model Year 2019). Notwithstanding this option, Chrysler believes that the 

primary certification test fuel, using federal test procedures, should be E10 fuel at 9.0 psi RVP. 

Recommendation: Chrysler recommends that EPA adopt an E10, 9.0 psi RVP certification test 

fuel requirement, which is representative of real-world in-use conditions. Chrysler further 

recommends that EPA extend the option of using E10 fuel at 7.0 psi and ARB test procedures to 

be permanent (past Model Year 2019), at least until EPA and California can agree on a 

harmonized test fuel with a methodology for designating a certification fuel that is the 

predominate fuel in the marketplace. 

Organization: General Motors LLC (GM)
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GM supports the harmonization of Federal Tier 3 and California LEV III vehicle emission 

programs. While there are some differences in requirements, we continue to support permanent 

mutual reciprocity that allows OEMs to use one test fuel and its related testing regime per test 

vehicle, either LEV III or Tier 3, for purposes of both Federal and California certification. 

Reciprocity with CARB’s LEV III regulation should be applicable to all aspects of EPA’s Tier 3 

rulemaking: all test fuels, evaporative requirements, exhaust requirements, etc. 

Tier 3 and LEV III – Full Reciprocity should be made Permanent: Full and permanent 

reciprocity assures OEMs the option to certify to either Tier 3 or LEV III regulations (all 

aspects). Reciprocity is an essential compliance flexibility that minimizes duplication of 

emissions compliance efforts and minimizes development costs and workloads, without risking 

increase in vehicle emissions. 

We encourage and need EPA and California to extend permanent reciprocity (mutual 

acceptance) of either LEV III test fuel/testing or Tier 3 test fuel/testing. There shouldn’t be a 

requirement to use Federal test fuel/test procedures after MY 2019 for Tier 3 certification, as 

proposed. This is critical to facilitate OEM use of one fuel/one testing regime per vehicle model, 

a longstanding goal for harmonization between LEV III and Tier 3 standards toward “one 

national standard”. The purpose of the arbitrary date cutoff in the proposal is not clear. 

If permanent reciprocity is not possible, EPA should accept carry-over certifications on LEV III 

certification gasoline beyond MY 2019:

CARB cannot amend the LEV III regulations until after EPA finalizes Tier 3. Thus, there will be 

a significant period (at least a year or two) of uncertainty where each agency has different 

certification gasoline requirements. 

The proposed Tier 3 regulations allow manufacturers to use LEV III certification gasoline only 

through MY 2019. Beginning in MY 2020, all vehicles must be certified using Tier 3 

certification gasoline and carryover of emissions data is not allowed. (See 40 CFR 86.113-07, 

Fuel Specifications). If there is no permanent reciprocity, despite our strong support, then EPA 

should allow carryover of emissions data after MY 2019. Manufacturers tend to carryover 

emissions data for several years. Without an extension, this could result in manufacturers 

retesting and recertifying vehicles for no other reason than to change the certification gasoline. 

For example, a MY 2016 vehicle certified to LEV III standards on LEV III gasoline might be 

required to recertify on Tier 3 gasoline, rather than carry over the LEV III certification data 

through MY 2020 or even 2021 until a redesign requires a new certification. This would be an 

unnecessary waste of resources and we do not believe this is EPA’s intent. Consequently, we 

recommend that EPA allow carryover of certification data using LEV III gasoline through at 

least MY 2022. 

Organization: Mitsubishi Motors R&D America, Inc (MRDA)

In the current Tier 2 program, certification test fuel is Indolene (E0). The proposed Tier 3 

program introduces an ethanol-based certification fuel, i.e. E15 with a 9 psi RVP (Reid Vapor 

Pressure), while California’s LEV III program includes a California E10 certification test fuel 
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with a 7 psi RVP. In order to avoid duplicative certification testing and to support the production 

of 50-state vehicle fleets, we request that the Tier 3 Final Rule include permanent reciprocity of 

certification test fuel with California’s LEV III program. Specifically, we request that EPA 

permanently allow the optional use of LEV III certification gasoline and LEV III evaporative 

emissions test procedures as equivalent to federal certification fuel and evaporative emissions 

test procedures. This would allow OEMs the option of performing either procedure with its 

appropriate certification fuel to satisfy the regulatory requirement of BOTH agencies. 

-Toward EPA’s goal to harmonize with LEV III, we ask that EPA permanently allow the 

optional use of LEV III certification test fuel (E10, 7 psi RVP) and LEV III evaporative 

emissions test procedures, or Federal certification test fuel (E10, 9 psi RVP) and federal test 

procedures.

Our Response:

We recognize that test fuels are an important element of a national program. Vehicle 

manufacturers have emphasized in their comments the desire to reduce their test burdens by 

producing one vehicle that is tested on a single test procedure and on a single test fuel and that 

meets both California and federal requirements. Although we have been able to reasonably align 

the Tier 3 program with the LEV III program in most key respects, we recognize that the Tier 3 

and LEV III test fuels are different, and that some differences may still exist in emissions 

performance between vehicles tested on the two fuels. The largest difference between the two 

fuels is the Reid Vapor Pressure (RVP), and other differences in distillation properties and 

aromatic levels also exist (largely related to differences in actual in-use fuel nationally and in 

California). We are finalizing as proposed the requirement that manufacturers certify vehicles on 

the new Tier 3 E10 test fuels37 beginning with the first model year that a vehicle model is 

certified to the FTP NMOG+NOX Bin 70 or lower.38 (The heavy duty and evaporative and 

evaporative provisions are detailed in preamble Section IV.F.) This requirement may apply as 

early as MY 2017 for vehicles up to 6000 lbs GVWR and MY 2018 for vehicles greater than 

6000 lbs GVWR.39 This requirement also applies to vehicles certified at Bin 70 and lower that 

are brought into the Tier 3 program under the Early Tier 3 option described in preamble Section

IV.A.7.b, with the exception of the specific provision allowing the use of LEV III fuels discussed 

below. Beginning in MY 2020, all gasoline-fueled models will need to certify on the Tier 3 test 

fuels for all exhaust emission requirements, regardless of their certification bin.40 As discussed 

in preamble Section IV.A.7.c, manufacturers must also meet the 150,000 mile useful life 

requirements for NMOG+NOX standards for these same vehicles as they are certified to Bin 70 

and lower. 

During the transition period from Tier 2 fuel to the new Tier 3 and LEV III E10 fuels, 

manufacturers have indicated that they face a substantial workload challenge of developing and 

 

37 This includes fuels used for cold temperature and high altitude testing and durability requirements. See preamble 

Section IV.F. 

38 The lower Bins are Bin 0, Bin 20, Bin 30 and Bin 50.

39 Vehicles above 6000 lb GVWR choosing the alternative phase-in schedules described in preamble section 

IV.A.2.c generally would begin using the Tier 3 test fuels for MY2019. 

40 Diesel-fueled and alternative-fueled vehicles will continue to be tested on the fuels used under the Tier 2 program 

except for E85 fueled vehicles, for which we are finalizing new test fuel specifications (see preamble Section IV.F). 
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certifying each vehicle model to the two new fuels simultaneously. We recognize this 

transitional challenge and are including an additional option. We are finalizing as proposed an 

option that vehicles certified in MYs 2015 through 2019 to California LEV III standards using 

California LEV III E10 certification test fuels and test procedures can be used for certifying to 

EPA Tier 2 or Tier 3 exhaust emission standards, including PM. A manufacturer may submit 

LEV III test data on vehicles tested using the new LEV III E10 fuels for Tier 2 or Tier 3 

certifications. Consistent with existing Tier 2 policy, EPA may test vehicles certified to Tier 2 

standards using LEV III test results on Tier 2 fuel for confirmatory or in-use exhaust testing. For 

vehicles certified in MY 2017 through 2019 to Tier 3 standards using LEV III E10 fuels, EPA 

will only use LEV III E10 fuels for confirmatory and in-use testing (except for high altitude or 

cold CO and hydrocarbons testing, as described below). Vehicles certified to the provisions of 

Early Tier 3 (preamble Section IV.A.7.b) will be treated the same as Tier 3 vehicles certified in 

MY 2017. For example, for MY 2015 and 2016, EPA will consider Early Tier 3 vehicles to be 

part of the Tier 3 program for purposes of fuel-related testing obligations. We will not accept test 

results using LEV II fuels for Tier 3 vehicle certification, including Early Tier 3 certifications, 

with the exception of the PZEV exhaust carry-over provision described below. 

California does not have fuel specifications for high altitude testing or cold CO and 

hydrocarbon testing. For this reason, we are finalizing that for vehicles that manufacturers 

choose to certify using LEV III fuel and test procedures, manufacturers must use programspecific federal test fuels to comply with these federal-only requirements (i.e. Tier 2 vehicles will 

use Tier 2 fuel and Tier 3 vehicles will use Tier 3 fuel). Similarly, high altitude and cold CO and 

hydrocarbon confirmatory and in-use testing for these vehicles will be performed on the federal 

fuel that the manufacturer is required to use at certification as specified above regardless of 

whether LEV III or federal fuel is used for other testing. 

We proposed the requirement that after MY 2019, all Tier 3 certification, confirmatory 

and in-use emission testing be required to use only the proposed Tier 3 E15 test fuel because it 

was believed to be a worst case fuel for emissions. Because we are finalizing Tier 3 E10 test 

fuels which are very similar as explained above to LEV III E10 test fuels, and not considered a 

worst case fuel, we are not finalizing the requirement for all testing to be performed on Tier 3 

E10 test fuel. Instead, for certifications after MY 2019, EPA will continue to allow LEV III test 

results to be submitted for certification to Tier 3 standards, consistent with protocol under the 

Tier 2 program. However, if a manufacturer chooses to submit certification results for 

compliance with Tier 3 standards using the LEV III test fuel, then for confirmatory and in-use 

testing we will hold vehicles to the Tier 3 standards while using the Tier 3 fuel in addition to the 

LEV III test fuel; we will not allow new or carry-over certifications using LEV II or Tier 2 

certification test fuels after MY 2019. CARB has indicated that they will accept Tier 3 test data 

(on federal certification test fuels) to obtain a California certificate as early as MY 2015. In this 

manner manufacturers should be able to avoid compliance testing on more than one fuel, since 

vehicles certified to Interim or Final Tier 3 status using federal certification test fuels could also 

obtain LEV III certification.
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Auto industry commenters noted that the LEV III program provides an allowance for 

manufacturers to carry over PZEV-certified vehicle exhaust data41 from the LEV II program into 

LEV III compliance in MY 2015 through MY 2019. Thus, CARB allows these PZEV vehicles 

to use emission testing results using LEV II fuel (i.e. California Phase II test fuel) to meet the 

LEV III obligations. The commenters suggested that EPA allow manufacturers to carry over 

such PZEV 150,000 mile useful life exhaust emission data to meet the Tier 3 standards. We 

agree that this approach is appropriate during the transition, and we are finalizing this provision 

for MY 2015 through MY 2019, including allowing Early Tier 3 compliance at the Bin 30 level 

as a combined NMOG + NOX standard. EPA will hold vehicles certified using this provision to 

the Tier 3 emission requirements when they are tested on the LEV II fuel for confirmatory and 

in-use. Compliance testing of these vehicles for all other Tier 3 obligations (i.e., high-altitude 

testing and Cold CO and hydrocarbons testing) must be performed using Tier 3 fuel, and these 

vehicles will be required to meet the Tier 3 standards for Bin 30.

4.5.4. Potential Implications on CAFE Standards, GHG Standards, and Fuel Economy 

Labels

See 78 FR 29912-29913, May 21, 2013 for full details.

4.5.4.1. Need for Adjustment to GHG, CAFE, and Fuel Economy Labeling Program 

Calculations

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Maintain Consistency with CAFE and Gas Guzzler Regulations: While Tier 3 is predominantly a 

criteria emissions regulation, proposed changes to the energy content (percent ethanol) of the 

certification test fuel and proposed requirements to test on four wheel drive dynamometers 

(dynos) significantly impact vehicle fuel economy. The changes proposed by EPA are not 

consistent with statutory law, the regulatory history and intent of the CAFE and GHG programs, 

or the 2017-2025 greenhouse gas and fuel economy agreements signed by EPA, NHTSA, 

California, and many automobile manufacturers governing the calculation and stringency of fuel 

economy values for CAFE and gas guzzler tax purposes. The Energy Policy and Conservation 

Act (EPCA) specifies that EPA determine the manufacturer’s CAFE value for passenger 

automobiles using the “same procedures for passenger automobiles the Administrator used for 

model year 1975...or procedures that give comparable results.” Section 503(d) of EPCA 

prohibits EPA from changing the stringency of the CAFE standards through test procedure 

changes. We therefore request that EPA comply as soon as possible with its legal obligation to 

issue fuel economy test procedure adjustments. 

 

41 California’s PZEV exhaust standards are the same as their SULEV standards and the Tier 3 Bin 30, and are 

certified to a 150,000 mile useful life. 
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EPA’s proposed changes to dyno requirements and to the ethanol content of test fuel would 

directly impact the measurement of fuel economy, which is used for CAFE reporting, for fuel 

economy labels and the Gas Guzzler Tax and for compliance with the two GHG rules. Industry 

recommends that EPA reconsider these proposals and instead adopt industry’s suggested 

modifications below in order to avoid introducing significant and costly changes to the fuel 

economy procedures. 

Organization: BMW of North America, LLC

Furthermore, BMW urges EPA to adjust the fuel economy test procedures for Corporate Average 

Fuel Economy (CAFE) in order to account for the substitution of E0 with E10. If not adjusted, 

fuel economy testing with E10 would result in a more stringent CAFE standard. 

Organization: Volvo Car Group

Emissions and GHG require the same test procedures and certification fuels. Thus, it is not only 

emissions that are becoming more stringent but also the GHG/CAFE indirectly through enhanced 

requirements regarding testing. 

Organization: Mitsubishi Motors R&D America, Inc (MRDA)

EPA needs to modify the fuel economy equations to account for the introduction of an ethanolcontaining certification fuel; therefore, we request the following: EPA must establish new fuel 

economy and CREE equations for ethanol certification fuels in the Tier 3 rulemaking. An Rfactor of 1 in the fuel economy and CREE equations is considered appropriate based on industry 

analysis.

Organization: National Automobile Dealers Association (NADA)

Clearly, engineering and technology resources necessary to meet Tier 3 compliance will directly 

compete with those necessary to meet GHG reduction mandates. Given EPA’s recognition of the 

need for a mid-term review process to assess critical assumptions associated with it’s MY 2017-

25 GHG mandates, the agency should recognize similarly the importance of revisiting critical 

assumptions associated with its Tier 3 regulations. In addition, the apparent benefits that 

appropriate fuel designs (i.e., low-sulfur content) offer for GHG reduction strategies should in 

the context of the mid-term review and otherwise. 

NADA concurs with suggestions made in the joint comments of the Alliance of Automobile 

Manufacturers and the Association of Global Automakers regarding the need to avoid 

introducing unnecessary, significant, and costly changes to fuel economy procedures that could 

negatively impact fuel economy rating, fuel economy labeling, and CAFE requirements. 

Organization: Advanced Biofuels USA (ABFUSA)
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In order to provide equality in EPA fuel economy calculations for higher octane, higher ethanol 

fuels, the “R” fuel energy content factor should be set at “1.” This change is necessary since EPA 

has previously recognized that the engine technology used to set the “R” in the 1970s has 

reached levels of efficiency not envisioned at the time and as a result the factor does not 

represent the current reality. 

Organization: American Coalition for Ethanol (ACE)

While discussion of the ‘R-factor’ is not technically part of this rulemaking, ACE agrees that the 

current fuel economy ‘equation’ unfairly punishes ethanol blends based on old data, primarily 

due to an out-dated ‘R-factor.’ EPA correctly notes that change in fuel economy is not directly 

proportional to change in energy content of the test fuel, and mentions that manufacturers have 

suggested that a higher R value may be warranted. ACE believes more current and accurate data 

has been available for some time, and supports EPA’s continued investigation into the issue, and 

looks forward to that hurdle being removed in the near future.

Organization: Clean Fuels Development Coalition (CFDC)

There are other impediments to widespread commercialization of higher octane ethanol fuels and 

one is the “R” factor noted in the NPRM and what appears to be a failure to recognize increased 

efficiencies since the original “R” factor formulas were established. 

Our Response:

EPA agrees with the commenters that action is needed to assess and potentially address 

the impact of changing test fuel on compliance with GHG, CAFE, and fuel economy labeling 

program requirements. We further agree that the adjustments should be such that the stringency 

of these programs is not affected. The preamble to the final rule discusses our future plans to 

obtain the data for future action in these areas. Note that at this time EPA is not adopting any 

new testing requirements for 4WD dynamometers.

4.5.4.2 Test Procedure Adjustments

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Applicable Law Requires Test Procedure Adjustments (TPAs): The Tier 3 NPRM proposes 

lower octane ethanol containing test fuel and dyno requirements which impact CO2, fuel 

economy, and the measurement of fuel economy for labeling, CAFE, the Gas Guzzler Tax, 

GHG, and medium-duty chassis cert compliance. EPA did not address the changes to measured 

fuel economy that will be caused by the proposed changes to test fuel and dyno requirements in 

the Tier 3 NPRM, nor the costs and benefits of the proposals. Instead, EPA’s supporting analyses 

simply alluded to a “future action” which would address these impacts. Deferring consideration 
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of fuel economy impacts from test procedure changes runs counter to EPA’s own rules (50 Fed. 

Reg. 27183, 1985) that require EPA to issue test procedure adjustments at the same time that it 

promulgates final regulations incorporating the test fuel and dyno changes. In addition to 

statutory and regulatory requirements, EPA must adhere to the commitments entered into 

between the agencies and manufacturers for achieving the 2012-2016 and 2017-2025 GHG rules. 

The Alliance and Global Automakers request that EPA comply as soon as possible with its legal 

obligation to issue fuel economy test procedure adjustments.

Whenever EPA modifies the test procedures for measuring fuel economy, it is required by law to 

give adjustments for measured fuel economy to compensate for the changes. 49 U.S.C. Chapter 

329 sets forth the statutory provisions relating to CAFE. The test procedures to be used for 

calculating CAFE are addressed in 49 U.S.C. §32904(c), which reads in relevant part as follows: 

“The Administrator shall measure fuel economy for each model and calculate average fuel 

economy for a manufacturer under testing and calculation procedures prescribed by the 

Administrator. However ... the Administrator shall use the same procedures for passenger 

automobiles the administrator used for model year 1975 (weighted 55 percent urban cycle and 45 

percent highway cycle), or procedures that give comparable results.” Will not 

The requirement for "procedures that give comparable results" indicates that when EPA 

promulgates changes to the test procedures that have an impact on the CAFE results for 

manufacturers, the method of calculating CAFE should be modified so that the results are 

comparable to those that would have been obtained in the absence of any change to the test 

procedures. Such modifications are commonly referred to as TPAs. This section imposes a 

"comparability" requirement on EPA: EPA must issue adjustment factors upon changing 

emissions or fuel economy test procedures so that measured fuel economy is comparable to 

results obtained using the 1975 test procedure. Attached as Appendix 7 is a discussion of the 

statutory and other requirements for EPA to issue TPAs for the test fuel and dyno requirement

changes being proposed in the Tier 3 rule. 

Organization: Mitsubishi Motors R&D America, Inc (MRDA)

Fuel Economy and CREE Equations: With the introduction of an ethanol-containing certification 

fuel in the Tier 3 NPRM, there will be implications upon vehicles’ fuel economy due to the 

lower energy content of ethanol-containing fuels. Under the Energy Policy and Conservation Act 

(EPCA), EPA must ensure that fuel economy test procedures for passenger cars produce results 

comparable to the 1975 fuel economy test procedures. The 1975 test procedures are based on the 

use of EC) certification test fuel. A change in the ethanol content in the certification test fuel will 

result in changes to fuel economy calculations, and therefore an adjustment factor is necessary to 

produce comparable results to the 1975 test procedures. The current R-factor of 0.6 was 

established using an EO certification test fuel. Changing the certification test fuel to an ethanolcontaining fuel severely impacts the calculation for fuel economy, and therefore requires an 

adjustment to the R-factor. 

Fuel Economy/CREE Equations: EPA must establish new fuel economy and CREE equations, 

with an R factor of 1 for ethanol-containing certification fuels in the Tier 3 rulemaking.
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Organization: National Corn Growers Association (NCGA)

Fuel economy testing originated in 1975 using the FTP-75 procedure and a pure hydrocarbon 

certification fuel with a specific gravity of 0.739 and a carbon weight fraction of 0.866. EPA is 

required to provide average fuel economy adjustments for test procedure changes that would 

cause a vehicle to achieve fuel economy results different from those that would be achieved 

under the 1975 test procedure. Changes in test fuel energy content qualify as a test procedure 

change that requires an adjustment. 

EPA has proposed new certification fuels containing ethanol with slightly lower net heating 

values on a per gallon basis. A simple way to adjust for energy content for vehicles not designed 

and optimized to use a mid-level blend high octane fuel is to use a ratio of the volumetric energy 

content of the new test fuel to that of the 1975 test fuel. EPA has proposed this approach in the 

past (10, 11). However, 30 years ago when EPA originally corrected for fuel changes, vehicle 

technology did not fully compensate for fuel energy changes. EPA modified the approach by 

adding the “R-Factor” which may be considered as the efficiency with which the vehicle engine 

adapts to fuel energy variations. A factor of 0.6 was derived from data gathered from vehicles 

from the 1970s and early 1980s. An R-Factor less than 1 implies the vehicle is less efficient on 

fuels with higher energy content than the 1975 test fuel and more efficient on fuels with lower 

energy content than the 1975 test fuel. 

EPA first applied the equation containing the R-Factor of 0.6 to a test fuel with oxygenates, 

California Phase 2 gasoline, in 1995 (12). In applying the 0.6 R-Factor EPA acknowledged 

“Data indicate that this [corrected] mpg value is partially corrected for the difference in fuel 

properties between Phase 2 test fuel and the 1975 EPA test fuel.”(13) The R-Factor of 0.6 was 

derived from vehicles that are now over 30 years old and nearly 20 years ago EPA acknowledged 

that the 0.6 value did not fully compensate for the fuel energy change and needed to be revised. 

Nonetheless, the factor of 0.6 is still in use today. 

Recent test data indicate a somewhat higher R-Factor than 0.6. The Auto-Oil test program on 

1989 model year vehicles (14) determined an R-Factor value of approximately 0.93. More 

recently, The U.S. Department of Energy published its own analysis indicating values ranging 

from 0.92 to 1.03 (15). For virtually all vehicles evaluated, the 95% confidence intervals shown 

include the 1.0 value that EPA initially proposed in 1976. The authors noted that: “Additionally, 

there is uncertainty present in the ASTM results for heating value, carbon weight fraction, and 

specific gravity that have not been included in the confidence intervals. Inclusion of these 

uncertainties would increase the confidence intervals.” Of course, in all these tests, the vehicles 

tested were not designed for a higher octane mid-level blend. 

We request that EPA review the R-Factor and determine whether the use of the value of 0.6 

would be an impediment to automakers to petitioning EPA for the use of a MLEB as a 

certification fuel and revise the R factor as necessary. 

Commenter footnotes

10 Impact of Gasoline Characteristics on Fuel Economy and its Measurements, 76-10 JLB. 

11 Corrections for Variations in Test Fuel Properties, EPA-AA-SDSB-84-3. 

12 EPA “Dear Manufacturer” Letter CD-95-09. 

13 Ibid. 
Tier 3 Summary and Analysis of Comments

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14 A. Hochhauser et al., “Fuel Composition Effects on Automotive Fuel Economy-Auto/Oil Air Quality 

Improvement Research Program,” SAE paper 930138, SAE International, March 1993. 

15 S. Sluder and B. H. West, (2013) Preliminary Examination of Ethanol Fuel Effects on EPA’s R-factor for Vehicle 

Fuel Economy; http://info.ornl.gov/sites/publications/Files/Pub42819.pdf, (2013). 

Our Response:

EPA has reviewed the text of the main comments from the Alliance and Global 

Automakers as well as appendix 7. EPA acknowledges that changes in testing and calculation 

procedures prescribed by the Administrator should give comparable test results to those used for 

the 1975 model year for passenger automobiles. In the NPRM we expressed our commitment to 

the principle that test procedure adjustments related to the change in test fuel properties will not 

affect the stringency of CAFE requirements for passenger automobiles and other vehicle classes 

covered by the CAFE requirements. EPA understands the need to make these adjustments in a 

timely manner and the manufacturers’ perspective that EPA should implement the new 

requirements for criteria pollutant emission testing, CAFE, and GHG at the same time. 

However, in the NPRM we deferred action on adopting a new R factor and other potential 

related adjustments because we did not have the requisite data on the new test fuel (E10) and the 

current test fuel (E0) on Tier 3 technology vehicles. Without the requisite data we could not be 

certain that the principles outlined in Appendix 7 would be followed. By requiring CAFE and 

GHG testing on Indolene or E0, the interim requirements established in the FRM assure that the 

stringency for the CAFE and GHG standards are not affected. This approach will also help to 

ensure that the data needed to make the test procedure adjustments based E0 and E10 emission 

test data on Tier 3 technology vehicles is available in a timely manner.

4.5.4.3. R-Factor Value

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

In addition, EPA proposes to change the definition of gasoline test fuels to include E10 and E15 

test fuels, but EPA does not propose to change the fuel economy equation used for CAFE to 

compensate for the change in volumetric energy content on Tier 3 compliant vehicles. EPA is 

obligated to release a new fuel economy equation for ethanol containing test fuels within the Tier 

3 Final Rule, and data supports that the R factor should be set to 1.0. Changing the fuel economy 

equation would be consistent with statutory law and the regulatory history governing the 

calculation of fuel economy values for CAFE and gas guzzler tax purposes. [EPA-HQ-OAR2011-0135-4461-A1, pp. 93-94]

EPA proposes to change the test fuel used by manufacturers to test vehicles for criteria emissions 

and GHG and Fuel economy from the current “Indolene” test fuel containing no ethanol to a test 

fuel with ethanol added. EPA proposes E15 for the ethanol level; elsewhere in these comments, 

the Alliance and Global Automakers discuss specific recommendations regarding the correct test 
Chapter 4: Proposed Vehicle Emissions Program

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fuel, level of ethanol, and Reid Vapor Pressure (RVP). The following discussion focuses on 

implementing required TPAs for ethanol containing fuel.

Data Supports R Factor = 1.0: A factor used to represent the response of a vehicle’s fuel 

economy to changes in the fuel’s ethanol content as measured by the fuel’s energy content is the 

“R Factor.” In a separate memorandum to the docket88 EPA concludes that an appropriate range 

for the R-factor for ethanol containing fuels is 0.8-0.9. This conclusion was based on an 

examination of the data in the EPAct study.89 The Alliance performed a similar analysis on this 

dataset and identified an error in the measured properties for one of the EPAct fuels that biases 

the R-factor results - correcting this error results in an R-factor of 0.96. Industry met with EPA 

on May 20, 2013 to review this new information and to provide the results of a reanalysis that 

included all the fuels included in the EPAct dataset except the above mentioned fuel (Attached as 

Appendix 8 is a summary of that reanalysis).

Industry met with EPA again on June 13, 2013, and reviewed a new report from Oak Ridge 

National Labs (ORNL) to determine R Factor.90 The report was based on an analysis of test data 

gathered in the U.S. Department of Energy (DOE) mid-level blends test program.91 The ORNL 

report concluded that:

“Analysis of city cycle Federal Test Procedure (FTP) fuel economy test results and fuel analyses 

from the catalyst durability study indicates that the average R-factor for modern vehicles is very 

close to unity at about 0.94±0.04 (or 0.96±0.04 if the one problematic vehicle omitted).” 

In summary, available data strongly supports an R-Factor equal to 1.0. Therefore, industry 

recommends that EPA adopt a fuel economy equation for gasoline fuels containing ethanol (i.e. 

E10, E15) with an R-Factor of 1.0 in the Tier 3 Final Rule. 

________________________________________________________________________

Commenter footnotes

88 EPA Technical Memorandum “Analysis of the Effects of Changing Fuel Properties on the EPA Fuel Economy 

Equation and R-Factor” by Aron Butler, et al.; also available in the docket (Tier 3 Docket #EPA-HQ-OAR-2011-

0135).

89 EPA Technical report “EPAct/V2/E-89: Assessing the Effect of Five Gasoline Properties on Exhaust Emissions 

from Light-Duty Vehicles Certified to Tier 2 Standards, Final Report on Program Design and Data Collection”, 

Report Number EPA-420-R-13-004, March 2013; also available in the docket (Tier 3 Docket #EPA-HQ-OAR2011-0135).

90 Oak Ridge National Laboratory, US Department of Energy, report “Preliminary Examination of Ethanol Fuel 

Effects on EPA’s R-factor for Vehicle Fuel Economy,” Report Number ORNL/TM-2012/198, June 2013; accessed 

at: http://info.ornl.gov/sites/publications/Files/Pub42819.pdf

91 West, Brian H., Scott Sluder, Keith Knoll, John Orban, Jingyu Feng, Intermediate Ethanol Blends Catalyst 

Durability Program, ORNL/TM-2011/234, February 2012, available at 

http://info.ornl.gov/sites/publications/Files/Pub31271.pdf

Organization: General Motors LLC (GM)

On page 29913 of the proposed rule, EPA discusses the potential impacts that the proposed 

gasoline test fuel change will have on corporate average fuel economy (CAFE). Additionally, 

EPA states that “it is almost certain that the same vehicle tested on a test fuel with 15 percent 

ethanol content will yield a lower fuel economy value relative to the value if it were tested on the 
Tier 3 Summary and Analysis of Comments

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current test fuel with zero ethanol content.” Indeed, the Department of Energy concluded after 

extensive testing of ethanol blended fuels on a fleet of late model U.S. vehicles: “‘Fuel economy 

was decreased ... consistent with the energy density of the test fuel.”1

Pursuant to 49 U.S.C. Section 32094 (c) and the provisions of 40 CFR 600.510-12(f), EPA is 

required to provide average fuel economy adjustments for test procedure changes that would 

cause a vehicle to achieve fuel economy results that would differ from results that would be 

achieved under the 1975 test procedure. However, EPA has proposed to defer any modifications 

to the average fuel economy calculations to a possible ‘future action’ based on the fact that the 

current gasoline fuel economy equation already contains an adjustment for the energy content of 

the fuel. This would be true and acceptable if the total adjustment in this equation was solely 

based on energy content. However, the current gasoline fuel economy equation includes a factor, 

commonly referred to as the R-factor, which provides a partial energy adjustment to more 

accurately represent the fuel economy that would be achieved if the vehicle were to be tested 

under 1975 conditions. The R-factor is part of the current test procedure adjustment that accounts 

for changes in test fuel energy content; therefore, changes to the R-factor must be made 

concurrently with changes to the test fuel.

One issue with the current R-factor of 0.6 is that it was developed under conditions where the 

energy content of the test fuel was tending to increase. It should not be applied when the energy 

content of the fuel is decreasing. As a matter of fact, in EPA technical report ‘Corrections for 

Variations in Test Fuel Properties’ (EPA-AA-SDSB-84-3), EPA states this concern as follows: 

“A second area of questionable accuracy with the GM approach [referring to the inclusion of an 

R-factor] occurs when the energy content per unit volume of the fuel decreases. In this case, the 

efficiency term reduces or discounts the calculated correction... It is unlikely that vehicles could 

tolerate a significant decrease in energy density of the fuel without experiencing an equivalent 

decrease in fuel economy.” 

Therefore, continued use of an R-factor designed for use with higher energy content test fuel is 

inappropriate when migrating to a lower energy content test fuel.

______________________________________________________________________________

Commenter footnote

1

K. Knoll, B. H. West, et al, Effects of Intermediate Ethanol Blends on Legacy Vehicles and Small Non-Road 

Engines, Report 1 – Updated.

Organization: Ford Motor Company (Ford)

Since discussions began in June 2012, the EPA and manufacturers have made considerable 

progress in developing the FE equation for low-level ethanol blends. This equation differs from 

the current “E0” equation in two respects: (1) an updated “R-factor” to better reflect the 

efficiency of current vehicle technology when operated on the proposed fuel, and (2) a factor for 

non-methane organic gases (NMOG) that accounts for the increase in oxygenated hydrocarbons 

resulting from the addition of ethanol to gasoline. While the inclusion of the NMOG factor in the 

equation has been a relatively straight-forward exercise, determining the most appropriate value 

for the revised R-factor has been a more complex task. Ford’s analysis of the EPAct2 data set 
Chapter 4: Proposed Vehicle Emissions Program

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(Alliance/Global Comments, Appendix 8) used an established R-factor methodology3 to show 

that once an anomalous fuel is removed, the data set strongly supports an R-Factor very close to 

“1”. This result was corroborated using a second, independent data set in a paper published by 

Oak Ridge National Laboratory4. Based on these findings, Ford agrees that the most appropriate 

value for the revised R-factor is 1, as proposed in the Alliance/Global comments.

Recommendation: Ford recommends that EPA adopt the fuel economy equation for E10 and E15 

test fuels as proposed in the Alliance/Global comments, with an R-factor equal to “1”, at the 

earliest possible date. Additionally, Ford recommends that EPA permit optional usage of the 

current “E0” fuel for all fuel economy purposes through 19MY for vehicles required to use E10 

or E15 for certification testing. 

Organization: Mitsubishi Motors R&D America, Inc (MRDA)

Recent analyses of data have demonstrated the Net Heating Value of ethanol-containing fuels 

result in an R-factor of 1. An R-factor of 1 is necessary to adjust the fuel economy values based 

on the proposed ethanol-containing certification fuel in order to be equivalent to the baseline 

1975 CAFE values. 

An R-factor of 1 in the fuel economy and CREE equations is considered appropriate based on 

industry analysis. 

Organization: Renewable Fuels Association (RFA)

EPA should set the “R-factor” for fuel economy calculations at 1.0 to reflect the latest research 

and to avoid unnecessarily complicating automaker compliance with CAFE standards. 

In its discussion of proposed changes to the certification test fuel, EPA briefly references 

potential implications for compliance with the CAFE program and GHG emissions standards. 

EPA states it is “...committed to the principle of ensuring that the proposed change in test fuel 

would not affect the stringency of either the CAFE or GHG emissions standards, and that the 

labeling calculations would be updated to reflect the change in test fuel (emphasis added).” In 

spite of this commitment, EPA fails to propose any actions to revise the “R-factor” used in the 

existing fuel economy equation. Maintaining the existing R-factor of 0.6 would indeed “affect 

the stringency” of CAFE standards and make it considerably more difficult for automakers to 

meet fuel economy requirements if the certification test fuel is E15 or other ethanol blend.

The R-factor was developed to account for a vehicle’s relative ability to compensate for changes 

in fuel energy content. The existing R-factor of 0.6 is based on data from vehicles tested more 

than 30 years ago and was first used in fuel economy calculations in 1988. Control systems in 

modern light duty vehicles have evolved substantially since establishment of the 0.6 factor, and 

recent testing data demonstrate modern vehicles are able to entirely compensate for changes in 

fuel energy content. A detailed analysis published in June 2013 by the Department of Energy 

(DOE) evaluated fuel economy data collected during mid-level ethanol blend catalyst durability 

testing to determine the proper value for the R-factor.1
Tier 3 Summary and Analysis of Comments

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According to the DOE work, “Calculating modern vehicle fuel economy with the existing CFR 

equation with an R factor of 0.6 when ethanol blends are used produces significant errors 

(emphasis added).” The DOE analysis found that the actual average R-factor for modern vehicles 

is “very close to unity” at about 0.94±0.04 (or 0.96±0.04 with one problematic vehicle omitted). 

DOE determined that fleet-wide average R-factor values for vehicles using E10 and E15 ranged 

from 0.95 to 1.03. Accordingly, the DOE researchers concluded, “The current factor of 0.6 

which is called out in CFR is clearly too low, and a proper factor for modern vehicles is closer to 

unity [i.e., 1.0], as might be expected from improved air/fuel ratio control common for more 

modern vehicles.” Based on the DOE work, EPA should revise its R-factor to 1.0. 

_____________________________________________________________________________

Commenter footnote

1

S. Sluder and B. H. West, (2013) Preliminary Examination of Ethanol Fuel Effects on EPA’s R-factor for Vehicle 

Fuel Economy; http://info.ornl.gov/sites/publications/Files/Pub42819.pdf

Organization: Mercedes-Benz USA, LLC on behalf of Daimler AG

Given that the volumetric energy content of an E25 Tier 3 fuel would be almost 9% lower than 

an E0 fuel, it is also necessary then to consider an R factor = 1. Per ‘Corrections for Variations in 

Test Fuel Properties, EPA-AA-SDSB-84-3’, the R factor, ‘considered as the efficiency with 

which the vehicle engine adapts to fuel variations’, should = 1 when an engine applies precise 

closed-loop feedback control for A/F ratio. Since the engine can take thermodynamic advantage 

of fuel properties but not fully adjust for volumetric energy content, as in the case of an E25 fuel, 

variations in volumetric efficiency are more related to engine-specific hardware and other 

vehicle attributes designed to optimize thermodynamic efficiency than to the specific test cycle 

itself. An R-factor of 0.6, as is currently the case, would result in approximately 5% volumetric 

fuel efficiency loss for an E25 fuel, which mathematically hinders any manufacturer seeking to 

certify a vehicle on such a fuel. Thus an R factor = 1 is a necessary step for the acceptance of 

mid-blend ethanol fuels. 

Organization: International Council on Clean Transportation (ICCT)

The ICCT has similar concerns on any future use of engines using E30. In addition, we are 

concerned that E30 could open the door to E30 credits against the CAFE and GHG standards, 

similar to what has already occurred for FFVs. It would be much better for EPA to focus on 

increasing the octane rating of all gasoline. The ICCT supports updating the R-factor in the 

carbon balance equation for NHV changes. Specifically, the R-factor determined by ORNL for 

Tier 2 vehicles without the data outlier should be used, or R=0.96. 

The R-factor is an adjustment made by EPA to maintain compatibility with the test procedures 

used in 1975 for calculating fuel economy, as required by the 1975 EPCA. The R-factor is used 

to adjust the FE test results for changes in the net heating value (NHV) of the test fuel. EPA is 

accomplishing this by incorporating the R-factor into the carbon balance equation, instead of 

doing the adjustment after calculation of the fuel economy.
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Specifically, the R-factor is the sensitivity of the fuel economy to changes in NHV. Ethanol 

blends reduce the NHV of the test fuel. To the extent that NHV affects engine efficiency, this 

change must be accounted for under the 1975 EPCA.

Current, an R-factor of 0.6 is in the regulations. This was based upon data submitted by GM and 

others in 1985 on primarily carbureted vehicles. In the past there was not a lot of variation in fuel 

properties of Indolene, so this R-factor had a minor effect and there was no need to revisit it.

However, switching to E10 as the test fuel will cause a much larger change in the NHV - about 

3.5% for E10 (and over 5% for E15). Using an R-factor of 0.6 would give an artificial upward 

adjustment of over 2% (0.4 x 5%) to E15 vehicles.

ICCT commends EPA for having the foresight to readdress the R-factor. A contractor report for 

EPA by ORNL, based upon test data on recent vehicles using E0, E10, E15, and E20, calculated 

R-factors for the entire fleet, Tier 2 vehicles only, and with and without exclusion of an outlier 

vehicle (12).

The existing R-factor is clearly outdated and needs to be replaced. Vehicles certified to Tier 2 

are representative of current vehicles and are the closest representation of future Tier 3 vehicles, 

so data from older non-Tier 2 vehicles should not be used. The Honda Accord data is clearly an 

outlier and is likely the result of an error in testing. It is standard practice in statistics to exclude 

such obvious outliers. Thus, the ICCT recommends that the R-factor found in the report for Tier 

2 vehicles without the outlier, 0.96, be adopted in the final rule. 

________________________________________________________________________

Commenter footnote

12 Sluder, S. and West, B., “Preliminary Examination of Ethanol Fuel Effects on EPA’s R-factor for Vehicle Fuel 

Economy”, ORNL report for EPA, June 2013.

Our Response:

As indicated by the comments, there is disagreement between EPA and the industry with 

regard to the appropriate value for the R-factor. The NPRM cited two memos discussing the 

issue, but in EPA’s view there was not adequate data at the time of the NPRM to settle on an Rfactor revised value for the proposal. Thus, no specific value was proposed and EPA indicated 

that a revised R-factor would not be included in the final rule. EPA met with the commenters on 

August 7, 2013 to further discuss the analysis they provided which supported their perspective 

that an R= 1.0 was justified. EPA’s view of the data was that a value of approximately 0.9 was 

more appropriate42. EPA and GM met the following day on the same issue, and at EPA’s 

request, GM provided additional input to clarify a few technical perspectives.43,44 There was 

agreement that further work would be helpful to understand the data relative to the effects of 

 

42 Passavant, G. (August, 2013). EPA, “Alliance, and Global Automakers Meeting on Issues Related to

Tier 3 Cert Fuel and the CAFE "R" Factor”. Memorandum to the docket.

43 Passavant, G. (August, 2013). “EPA and GM Meeting on Issues Related to Tier 3 Cert Fuel and

"R" Factor”. Memorandum to the docket.

44 Fronetti, S. (August 2013).”GM Input on R-factor”. E-mail from S Fronetti to G Passavant. 
Tier 3 Summary and Analysis of Comments

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other fuel qualities on the R-factor and that the data set had several limitations related to 

technology types and ethanol content of the test fuels. 

The current fuel economy equations already have a means by which to adjust for 

elements such as volumetric energy density, specific gravity and net heating value which are fuel 

specific. The R-factor is more vehicle technology related so it best assessed on vehicles using 

Tier 3 technology.45 The approach laid out in the FRM and prescribed in §86.600.113 will help 

to ensure that the R-factor is based on E0 and E10 emission results for Tier 3 technology 

vehicles. As mentioned in the GM comments, the use of an R=0.6 is not ideal with E10 

emission test results and is thus providing the manufacturers the option to use E0 fuel in litmus 

assessments if it does not think E10 test results with R=0.6 is appropriate. 

We acknowledge the comments of Mercedes Benz USA (MB) regarding the relationship 

of E25 and the R-factor. Fundamentally, the issue of the appropriate R factor value needs to be 

assessed since the test fuel is changing. We note MBs view that an R=1.0 is appropriate for E25, 

and will consider test data if and when E25 becomes a primary or optional test fuel.

We do not agree with the comments from the ICCT. They seem to misunderstand the role of the 

R value term in the fuel economy equation and believe it is already covered by the change in net 

heating value (NHV) for E10 versus E0 in the fuel economy equation. R factor is the efficiency 

with which the vehicle/engine adapts to changes in fuel qualities. It is determined empirically 

based on vehicle test data. We do not agree with ICCT that a value of 0.96 is appropriate 

because it is not based on the results for Tier 3/LEV III technology vehicles tested on Tier 

3/LEV III fuels. The approach laid out in the FRM will allow EPA to gather the requisite data 

and conduct the analysis needed to see if a change in the R factor value is needed and if so, what 

value should be proposed.

4.5.4.4. Related Test Procedure Adjustment Calculations

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA should address Fuel Economy and CREE Equations for E10-25 Certification Fuels as 

follows: 

The Tier 3 proposal requires that 50-state E10 certifications use ethanol test fuel for fuel 

economy label litmus tests and for fuel economy. This is not possible without an updated R 

factor and fuel economy equation. Measuring the oxygenates for all E10 or E15 tests is labor 

intensive, requiring ethanol and aldehyde measurement in the chemistry lab which is very 

expensive and delays results for a very small and negligible change in fuel economy. 

Oxygenated species contribution to fuel economy and CREE with E10 or E15 is insignificant 

(less than 0.005%) but will be included in the NMOG term in the denominator of the proposed 

 

45 The R-factor may be considered as the efficiency which the vehicle/engine adapts to changes in fuel qualities.
Chapter 4: Proposed Vehicle Emissions Program

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fuel economy equation below. The NMOG term is calculated based on the NMHC to NMOG 

equations proposed in §1066.665 in the Tier 3 Part 1066 test procedures without the requirement 

for direct measurement of ethanol and aldehyde. Accordingly, the Alliance and Global 

Automakers recommend the following equations (with an R factor of 1.0) be used for E10 and 

E15 fuel economy, CREE and ADCREE conversion factor calculations:

10−25 = (5174 × 104

× )/[[ × ( + 4)+(0.429 × )+(0.273 × 2)]x ] 

10−25 = ( /0.273)( + 4)+(1.571 × )+ 2

2 × = (5174 × 104× )/(0.273 × )=

Where: 

– 5174x104= density of H20 @ 60°F * SG of 1975 reference fuel * NHV of 1975 reference fuel 

– CWF is the carbon weight fraction of the test fuel 

– NHV is the net heating value of the test fuel [Btu/lbm] 

– HC is the total hydrocarbons [g/mi] in the exhaust gas 

– CO is the carbon monoxide [g/mi] in the exhaust gas 

– CO2 is the carbon dioxide [g/mi] in the exhaust gas

Organization: General Motors LLC (GM)

An added benefit of setting the R-factor at 1.0 is that it would simplify the fuel economy 

equation and avoid future controversy if EPA were to ever propose another test fuel.

GM proposes that EPA include this change in the final Tier 3 rule by establishing a new fuel 

economy equation for vehicles tested on Tier 3/LEV III E1x test fuels that includes an R-factor 

of 1.0. This equation would be:

FE = (5174x104x CWF) / {[(CWF x (NMOG + CH4)) + (0.429 x CO) + (0.273 x CO2)] x NHV} 

where,

– 5174x104= density of H2O @ 60° F x specific gravity of 1975 reference fuel x NHV of 1975 

reference fuel – CWF is the carbon weight fraction of the test fuel

– NHV is the net heating value of the test fuel [Btu/lbm]

– NMOG is the non-methane organic gas [g/mi] in the exhaust gas as determined in accordance 

with 40 CFR 1066 test procedures

– CH4 is the methane [g/mi] in the exhaust gas– CO is the carbon monoxide [g/mi] in the exhaust 

gas

– CO2 is the carbon dioxide [g/mi] in the exhaust gas 
Tier 3 Summary and Analysis of Comments

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It should be noted that although oxygenated hydrocarbons are an insignificant contributor to the

fuel economy value, their effect has been included by virtue of using NMOG in the equation. 

Organization: General Motors LLC (GM)

One of GM’s primary concerns with the use of any new certification test fuel, regardless of 

chemical composition, is the test fuel’s effect on CAFE fuel economy, which is intimately linked 

to EPA’s exhaust emissions regulations. The current fuel economy adjustment R-factor of 0.6 

was first developed by EPA and GM in 1984 as a means to compensate for drift in the 

composition and energy content of Federal emissions certification fuel relative to the original 

1975 emissions certification fuel. This practice established the precedent that each time the 

emissions certification fuel formulation changed, the fuel energy content would be partially 

normalized (to the extent of the R-factor) back to that of the 1975 certification fuel to reduce 

changes in fuel economy regulation stringency. Going forward, no vehicles meeting Tier 3 

emissions will use the open loop control systems that were used to develop the R-factor back in 

the 1970s and early 1980s. Modern closed loop control systems fully adjust for changes in the 

heating value of the fuel. Indeed they must do so to maintain stoichiometry and minimize 

emissions of HC, CO and NOx. An R-factor of 1.0 reflects the full control system adjustment to 

the fuel. However, the Test Fuel section of the introductory material of the NPRM states, “EPA 

will continue to investigate this issue (R-factor) and if necessary address it as part of a future 

action.” 

Our Response: 

EPA did not propose to change the fuel economy equations of 40 CFR 600.113 in the 

Tier 3 NPRM. The equations proposed by the commenter differ from those now in the CFR in 

that the R factor value is set at 1.0 (and this is not shown), the HC value is replaced by 

(NMOG+CH4), and an additive value of 5174 is missing from the denominator of the FE 10-25

equation because the R factor is 1. The term ADCREE is not used in the current CFR, but is 

reflected in an EPA guidance letter to the manufacturers.46 The manufacturers suggest that the 

use of NMOG + CH4 in the fuel economy equations provides sufficient accuracy relative to the 

measurement of aldehyde values. EPA is not adopting any changes to the fuel economy 

equations in the Tier 3 rule, but the commenters should raise these ideas in comments on the 

follow-on action where EPA proposes the test procedure changes related to the fuel economy 

equation. In that forum adjustment to the terms and values in the fuel economy equations and 

any related guidance letters can be fully considered. 

4.5.4.5. Timing for the GHG, CAFE, and Fuel Economy Labeling Program 

Adjustments

What Commenters Said:

 

46 CD 12-03.(February, 2012).” Analytically Derived CO2 and Carbon-Related Exhaust Emissions

(CREE) for Light-Duty Vehicles”.
Chapter 4: Proposed Vehicle Emissions Program

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Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA is Obligated to Release a New Fuel Economy Equation for Ethanol Containing Test Fuels 

Within the Tier 3 Final Rule: 

Under 49 U.S.C 32904(c) and 40 C.F.R. 600.510-12(f), EPA is required to provide average fuel 

economy adjustments for test procedure changes that would cause a vehicle to achieve fuel 

economy results that would differ from results that would be achieved under the 1975 test 

procedure. The current regulations contain a fuel economy equation with an R-factor equal to 0.6 

that applies to testing on “gasoline.” Additionally the regulations currently define E10 and E15 

fuels [§86.113-04(a); §86.113-07(a); and §1065.710(a)] as being gasoline. Hence when the 

NPRM proposed to change the test fuel to either E10 or E15 without changing the applicable 

mpg equation, the resultant proposed regulations could be interpreted as requiring use of the 

current equation with an R-factor of 0.6. This creates a change in test procedures relative to the 

1975 baseline required for the CAFE program. For this reason, EPA must adopt a test procedure 

adjustment to account for the change. EPA either needs to provide a separate test procedure 

adjustment to account for the effects of the test fuel change or it needs to make the necessary 

revisions to the mpg equation, including incorporating the appropriate R-factor, to appropriately 

adjust for the effects of the fuel change.

This situation arises as a result of the proposed regulations and hence must be resolved in the 

final regulations. EPA has indicated that it does not believe it can finalize the R-factor in the Tier 

3 rulemaking. While the agency has verbally committed to do a follow-up rulemaking to handle 

this issue, this will result in an unacceptable delay. Such a delay would result in a changed test 

procedure but without all of the conditions and consequences being established. This would 

make planning for compliance difficult. We believe that language that already exists in the 

current regulations plus what EPA has proposed in the NPRM sets up the conditions that 

effectively should enable EPA to resolve the R-factor issue in this rulemaking. In fact these 

conditions arguably require that it must be done in this rulemaking. The proposed test fuel 

change satisfies the five criteria in the Rules for issuing CAFE test procedure adjustment. First, 

preliminary EPA/auto industry testing has confirmed that a directional (downward) change in the 

measured fuel economy of an average vehicle can be anticipated from EPA’s proposed test fuel 

change. Second, this directional change in measured fuel economy can be quantified once 

sufficient testing has been performed to develop appropriate and reliable data. Third, the 

proposed FTP changes do not fall within the parameters of 40 C.F.R. § 600.510-86(f)(3), which 

is intended to close "loopholes" that may have permitted manufacturers to gain measured 

improvements in fuel economy without corresponding actual improvements in fuel economy. 

Fourth, the proposed FTP revisions are not the type referenced in 40 C.F.R. §600.510-86(f)(4), 

which relate to test procedure changes providing manufacturers with improved ability to receive 

credit for real fuel economy improvements. Fifth, the proposed FTP changes are being initiated 

and required by EPA, and not implemented solely by a manufacturer on its own initiative, in its 

own laboratory. Thus, EPA is required to issue appropriate CAFE adjustments for changes to the 

test fuel, with the appropriate R factor of 1.0. 

Organization: General Motors LLC (GM)
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In the NPRM, EPA indicates it would be evaluating whether R-factor changes should be 

included in a future action. GM sees no reason for delaying the establishment of an R-factor for 

the new EPA E1x test fuel as well as CARB LEV III E10 test fuel. We believe that there is 

sufficient data available for EPA to make the R-factor determination now and that the data 

supports the establishment of an R-factor value of 1.0, including a new report from Oak Ridge 

National Labs3and data analysis provided in the Alliance/Global comments. 4

GM is very concerned with this language leaving the R-factor of 0.6 in place and believes EPA 

must address the R-factor as part of Tier 3 rule-making instead of waiting and issuing a “Dear 

Manufacturer’s Letter” sometime in the future. The extra degree of certainty and expediency by 

doing so is needed by the automakers to assist in their compliance planning.

(B) The manufacturer must also use this E10 fuel for fuel economy measurements, with any 

appropriate corrections related to ethanol content in the fuel. 

EPA has long promised that it will revisit the correction factor (R-factor) regarding ethanol 

content.5 The final value of the R-factor and its timing are unknown. In Section II of these 

comments, GM recommends that EPA set an R-factor of 1.0. If EPA does not set the R-factor in 

time for these early certifications, then GM requests EPA give manufacturers the option to use 

today’s E0 fuel for fuel economy testing . Although this is a burden for manufacturers (dual 

testing, E0 and E10), the penalty of requiring the use of an inappropriate correction factor is 

much more damaging. 

__________________________________________________________________________

Commenter footnote

3

Oak Ridge National Laboratory, US Department of Energy, report ‘Preliminary Examination of Ethanol Fuel 

Effects on EPA’s R-factor for Vehicle Fuel Economy,’ Report Number ORNL/TM-2012/198, June 2013; accessed 

at: http://info.ornl.gov/sites/publications/Files/Pub42819.pdf

4

See Alliance/Global comments, Appendix 6: Reanalysis of R Factor Data.

Our Response:

EPA agrees that an assessment of the impact of the change in test fuel qualities on the 

measurement of fuel economy is needed and that test procedure adjustments should be made if 

appropriate. Referring back to the comments, the second point above “...this directional change 

in measured fuel economy can be quantified once sufficient testing has been performed to 

develop appropriate and reliable data. “ In the case of the Tier 3 rule there are two variables to 

consider: changes in fuel quality and changes in vehicle technology as a result of the new 

emission standards. Thus, we believe EPA’s approach as laid out in the FRM is appropriate. It 

does not change the fuel economy test requirements now specified in 600.113-12 are not 

changed. Test data based on Tier 3/LEVIII fuel in Tier 3/LEVIII technology vehicles will 

provide the data needed to determine any appropriate test procedure changes. The data available 

now such as that discussed in Appendix 8 of the Alliance and Global Automakers comments 

may inform the analysis but are not sufficient to meet the needs of the assessment since it does 

not focus fully on the fuels and vehicles of interest. EPA agrees with GM that fuel economy 

testing should be permitted on E0 fuel if the R factor is not revised in the Tier 3 rule. In fact it 

the use of E0 will be required for fuel economy testing.
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Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

While no substitute for adopting a new fuel economy equation in the Tier 3 Final Rule, EPA 

should also optionally allow manufacturers to continue to perform fuel economy testing on E0. 

As vehicles are certified on the new test fuel, it becomes important to set up processes that will 

minimize manufacturer testing burdens and maintain a level playing field for fuel economy 

labeling because not all competing products will phase-in to the new test fuel at the same time. 

The fuel economy label for a product adopting new ethanol test fuel should still accurately 

reflect its comparative performance relative to a competing product certified on non-ethanol test 

fuel. Without adopting a new fuel economy equation appropriate for ethanol-containing fuels, 

EPA creates a period of uncertainty where vehicle programs, which begin development work 

several years before certification, must continue to develop and establish targets based on the 

assumption that E0 will be used for all fuel economy measurements. Allowing optional use of E0 

test fuel for a predefined period of time would allow manufactures to better manage the task of 

migrating to the new fuels and prevent disruption of vehicles program that are underway when 

the new fuel economy equation is made available. We recommend that EPA allow the optional 

use of E0 test fuel for fuel economy purposes as an option through MY 2019 to help to mitigate 

level playing effects due to different products phasing-in at different times and to manage 

uncertainly regarding the timing of the new fuel economy equation. 

Organization: Ford Motor Company (Ford)

Although the Tier 3 NPRM proposes a new E15 certification fuel, it does not provide a new fuel 

economy (FE) equation that can be appropriately used for such low-level ethanol blends–

including CA LEV III E10–for fuel economy, CAFE or “litmus test” purposes (EPA does note 

that this could be accomplished via a “future action”). As a result, several aspects of the rule 

cannot be carried out by manufacturers as proposed, including the requirement that E15 be used 

for all fuel economy purposes when required for certification (§86.113-07 (a)(1)) and that CA 

E10 be used for fuel economy testing for 50-state certification in 2015 and 2016 model years 

(MY) (§ 86.113-04 (a)(2)(ii)(B)). Although these requirements could be changed in the final rule 

to alleviate the immediate concerns regarding their non-executable nature, the absence of firm 

timing for the adoption of a fuel economy equation for E10 and E15 (E1x) still creates a period 

of uncertainty for manufacturers, who must continue to use the current “E0” fuel not only for 

official testing but also as a basis for development testing and program target setting, both of 

which take place several years ahead of final certification. To address this uncertainty, we 

recommend that in addition to prompt adoption of the new FE equation for E1x fuels, EPA also 

specify a pre-defined period of time where testing on “E0” would remain optional for FE 

purposes, independent of the date the new E1x FE equation is eventually finalized. Such a 

provision would also allow manufacturers to phase the new fuel into FE testing in such way to 

avoid mid-stream program disruptions, better manage carryover issues, and mitigate any 

competitive issues related to competing products moving to the new test fuel in different model 

years. 

Our Response:
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Manufacturers have presented two points of view with regard to when the potential new 

requirements (including a revised “R” factor and other possible test procedure 

changes/adjustments related to CAFE, GHG, and fuel economy labeling) should take effect 

assuming a future rule is proposed and finalized. Some have stated that use of the new provisions 

should be available for use as soon as possible after the rule is completed. This would minimize 

the need for any future duplicate emission testing and put manufacturers on course for fully 

aligning with the new requirements quickly. Others have asked that there be lead time provided 

before the application of the new requirements becomes mandatory. The manufacturers have 

expressed concern that the use of the new requirements more quickly by one manufacturer versus 

another could create a competitive imbalance. At the same time, manufacturers do not 

necessarily want to be forced to certify all products to the new requirements by a cut-off date 

(e.g., 2020 model year) without EPA consideration of phase-in or phase-out provisions and data 

carryover. 

EPA understands the manufacturers’ various issues and concerns in this area. Based on 

the information available at this time, EPA is expecting to allow the optional use of any future 

adjustments for compliance calculation and labeling purposes as soon as the potential future rule 

mentioned above becomes effective. Furthermore, we expect that the mandatory use of any such 

new adjustments with all Tier 3 certifications would be required for the 2020 MY. These initial 

timing considerations are subject to revision based on timing of the completion of the future 

action and the data and record developed in that future rulemaking.

4.5.5. Consideration of Nonroad, Motorcycle, and Heavy-Duty Engine Emissions Test 

Fuel

What Commenters Said:

Organization: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

EPA believes it is important that the emissions test fuel for these other categories reflect realworld fuel qualities but has elected to defer moving forward now pending additional analysis of 

the impacts of changing the test fuel specifications for the wide range of engines, vehicles, 

equipment and fuel system components that could be impacted. We would suggest that one 

benefit of moving to an E10 test fuel, instead of E15, would be that EPA can then identify a 

single certification fuel for all gasoline engines and vehicles.

Organization: Outdoor Power Equipment Institute (OPEI)

The Outdoor Power Equipment Institute (OPEI) is pleased to provide initial comments in 

response to EPA’s Notice of Proposed Rule Making (NPRM) “Control of Air Pollution from 

Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards”. Specifically, the OPEI 
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comments address changes to gasoline certification test fuels, and the implications to non-road 

engines. 

OPEI is the major international trade association representing the manufacturers and their 

suppliers of small off-road engines and consumer and commercial outdoor power equipment 

(OPE). These products are commonly found in most American households and include products 

such as lawnmowers, garden tractors, utility vehicles, trimmers, edgers, chain saws, snow 

throwers, tillers, leaf blowers and other lawn and garden implements. While OPE consumes a 

small percentage of the nation’s fuel supply, their ownership by the American consumer is 

ubiquitous. As a result, there exists an inventory of as many as 200 million OPE legacy products 

currently in use. 

In response to Section IV.D.5 of the subject NPRM (page 29914) “Consideration of Nonroad, 

Motorcycle, and Heavy-Duty Engine Emissions Test Fuel”, and specifically whether a different 

test fuel (other than E15) would be more appropriate for the subject categories, OPEI is pleased 

to provide these initial comments: 

Increasing the use of mid-level ethanol blended fuels in retail fuel distribution as well as for 

future certification test fuel presents enormous risks, burdens, and challenges to OPE 

manufacturers and users. As stated in EPA’s E15 partial waiver decision notice (FR Vol. 75, No. 

213, page 68098) “The Agency has reasons for concern with the use of E15 in nonroad products, 

particularly with respect to long-term exhaust and evaporative emissions durability and material 

compatibility” as a result of “more basic engine designs”. Similarly, in section IV.D.5 of the 

subject NPRM (page 29914), EPA recognizes small non-road engine concerns stating “Because 

of lower level of technology, emissions from these engines are potentially much more sensitive 

to changes in fuel quality.” These concerns, as expressed by EPA, are consistent with those of 

the small spark-ignited engine and outdoor power equipment industries. 

Currently, there are numerous technical challenges and constraints for legacy and current 

production that were developed, manufactured and certified to EPA’s current E0 certification 

fuel. These constraints and challenges would first need to be resolved through practical 

regulatory and engineering solutions (that are a long way from being developed or 

implemented)—before making any certification test fuel change beyond E10 for these products. 

With few exceptions, small spark-ignited engine powered OPE is not designed or warranted to 

run on gasoline fuel containing more than 10 percent ethanol by volume (E10). At its fuel 

distribution core, today’s carburetor technology still widely limits the reliable ethanol operating 

range of most small spark-ignited engines. While carburetors can be calibrated to allow product 

to run on fuels exceeding E10, the limited 10% operating range does not change. Additionally, 

sensitive and critical fuel system components and materials can be damaged by E-15. 

Consequently, when running carbureted engines on fuel outside their designed operating range, 

excessive heat, emissions and safety issues may result. Accordingly it is critical that every retail 

gas station continue to offer dedicated E10 or less fuel pumps to support the growing 

contingency of legacy product independent of future certification fuels. 
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Small spark-ignited engines may ultimately be designed to run on mid-level ethanol fuel blends, 

given adequate lead time for design changes and assurance that the retail fuel ethanol content is 

within a limited and acceptable range of the certification test fuel specified by EPA for emissions 

compliance. However, any consideration of certification test fuel changes should recognize the 

significant investments and lead time required of manufacturers. An extended time period would 

be required to complete design and recalibration work as well as necessary consumer education 

programs for each new certification test fuel. Therefore small spark-ignited engine certification 

test fuel changes would need to be nationally harmonized based on a limited number of re-design 

iterations, representative of established and consumer accepted (“real world”) fuels, not based on 

incremental changes as required by the Renewable Fuels Standard (RFS). 

Non-harmonization of certification test fuel for small spark-ignited engines will further 

complicate manufacturing and consumer decision making. Similar products each designed to 

operate on unique certification test fuels will add consumer confusion and increase the potential 

of detrimental misfueling. In line with today’s market fuel, recent California Air Resources 

Board (CARB) rulemaking established E10 certification test fuel requirements for 2020 and later 

for small spark-ignited engines. CARB’s new regulation permits the use of E10 certification test 

fuel as early as 2013 and suggests no certification test fuel changes thereafter. Similarly, EPA 

worked with the industry on a small spark-ignited engine direct rule amendment which permits 

E10 certification fuel through 2019. While this effort is appreciated, the new rule does not 

provide the harmonization certainty needed beyond 2019. OPEI recommends a continued 

optional alignment path with CARB E10 certification test fuel beyond 2019. 

In summary, today’s E-15 certification test fuel proposed rulemaking for motor vehicles is not 

appropriate for small spark-ignited engines. In response to EPA’s request for comments 

regarding appropriate certification test fuels for small spark-ignited engines, OPEI recommends a 

continued harmonization path with CARB E10 certification test fuel for 2020 and later model 

years. Furthermore, aside from further CARB E10 certification test fuel harmonization, OPEI 

recommends that longer-term certification test fuel rulemaking for small spark-ignited engines 

be postponed until the future of the RFS and retail fuel marketplace is clear. 

At this time OPEI’s recommendations are limited to EPA’s specific request for comment from 

the nonroad industry in section IV.D.5 of the subject NPRM (page 29914). Consequently, OPEI 

may have further comments, concerns or issues with the NPRM as it continues to review the 

potential impact on its members. 

Organization: Truck and Engine Manufacturers Association (EMA)

Exhaust emissions certification test fuel for other heavy-duty, motorcycle, and nonroad 

categories:

EPA has requested comment regarding the implications of changing the exhaust emission 

certification test fuel for gasoline-fueled nonroad engines (large spark-ignited (LSI), small 

sparkignited (SSI), recreational vehicle, marine spark-ignition), motorcycle, and “other” heavyduty engines in a future rulemaking. (78 Fed. Reg. at 29919.) 
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Those product categories fall into a broad category of engines, vehicles, or equipment that EPA 

previously determined would be adversely affected by the use of gasoline blends greater than 

E10. (75 Fed. Reg. No. 213, 68094-68510, November 4, 2010; 76 Fed. Reg. No. 17, 4662-4683, 

January 26, 2011.) Those products are substantially different from the 2001 and newer light-duty 

vehicles that EPA determined would not be adversely affected by gasoline with an ethanol 

content up to E15. EMA agrees with EPA’s previous determination regarding product categories 

deemed to be adversely affected by E15, but we remain concerned about the misfueling controls 

and fuel availability issues that we identified in comments provided during the E15 waiver 

determination process. (Docket No. EPA-HQ-OAR-2010-0448; Comments of the Engine 

Manufacturers Association, January 3, 2011). During the waiver determination process, EPA 

asserted that both the potential for misfueling, and continued availability of E10 and lower 

ethanol blends, were adequately controlled. However, in the Proposed Rule, EPA suggests that it 

is contemplating future rulemakings whereby the products deemed to require E10 and lower 

blends would be redesigned to utilize the proposed light-duty E15 certification test fuel and the 

misfueling mitigation measures would be revised. 

As we have discussed with EPA, and as we set forth in EMA’s comments submitted during the 

E15 waiver decision process, engine manufacturers cannot make product changes associated 

with frequently-changing certification test fuel or marketplace gasoline-ethanol blends. The 

light-duty Tier 3 proposed change to E15 certification test fuel does not appear to be the end but, 

rather, the beginning of changes driven by the requirements of the Renewable Fuel Standard 

(RFS-2). The stated premise for the proposed change to E15 certification test fuel in the pending 

rulemaking is EPA’s intent to reflect marketplace fuel for the next 10 to 15 years. (78 Fed. Reg. 

at 29909.) However, increasing ethanol content requirements required by the RFS-2 are not 

being met by increased consumption of E85 as originally projected by EPA. In addition, in 

separate action, EPA and the National Highway Traffic Safety Administration have promulgated 

regulations that require significant increases in light-duty fuel efficiency. 

As noted in the preamble, the ARB LEV III standards require use of an E10 certification test fuel 

for on-highway vehicles. Similarly, ARB recently adopted regulations that require all nonroad 

spark-ignition exhaust emission certification requirements to be met utilizing E10 certification 

test fuel beginning in model year 2020. To facilitate the transition to E10 fuel, ARB’s nonroad 

spark-ignition regulations allow the use of E10 certification test fuel at the manufacturer’s option 

for the 2013 through 2019 model years. EPA is in the final stages of promulgating a regulatory 

change for nonroad small spark-ignition engines to allow an option to utilize the ARB E10 

certification test fuel through the 2019 model year, after which time the option will no longer be 

available. (Heavy-Duty Engine and Vehicle, and Nonroad Technical Amendments; Direct Final 

Rule, June 17, 2013; 78 Fed. Reg. No. 116, 36369, 36384-36385.) Those changes will provide 

for harmonization of EPA and ARB exhaust emission test fuel requirements in the near term, but 

will result in disharmony between EPA- and ARB-required certification test fuels beginning in 

the 2020 model year. As noted above, engine manufacturers cannot make product changes 

associated with such a frequently changing certification test fuel scheme. 

EMA recommends that EPA adopt the same E10, 9 psi RVP certification test fuel for heavy-duty 

on-highway, motorcycle, and nonroad categories that EMA recommends EPA adopt for Tier 3 

on-highway vehicles. EPA should adopt stable, harmonized certification test fuel requirements. 
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Evaporative emission certification test fuel for nonroad categories:

Currently, EPA specifies E10 certification test fuel for all nonroad spark-ignition engine 

evaporative compliance determinations. (40 CFR Part 1060.) The current E10 test fuel is not 

prescribed beyond a splash blend of E0 certification test fuel and 10 percent volume ethanol. 

EPA requests comments on the impact on evaporative emissions if EPA were to require 

certification test fuel to be 10 psi RVP E10. (78 Fed. Reg. at 29895.) 

EMA recommends that EPA specify that the certification test fuel for evaporative emission 

certification for all nonroad categories be E10 with an RVP of 9 psi. The use of an E10 test fuel 

with 9 psi RVP will provide manufacturers the ability to design and implement emission control 

systems that meet both ARB Small Off-Road Engine and EPA Nonroad Small Spark- Ignited 

Phase 3 requirements, which balances the lower 7 psi RVP California certification test fuel 

against the higher testing temperature requirements imposed by ARB. EPA should propose and 

adopt a change to 40 CFR Part 1060 to replace the splash blended E10 with the regulatory 

certification test fuel specification. EMA looks forward to working with EPA to adopt such 

changes. 

Organization: National Marine Manufacturers Association (NMMA)

The California Air Resources Board (CARB) recently approved a staff recommendation 

requiring all nonroad spark-ignition exhaust emission certification requirements to be met 

utilizing E10 certification test fuel beginning in model year 2020. NMMA testified at the CARB 

Board hearing requesting that the board also allow for the use of an alternative California 

certified advanced biofuel, if available. 

Organization: Renewable Fuels Association (RFA)

We are disappointed that EPA did not require that the proposed new certification fuel also apply 

to non-road and small engines. We believe it is necessary to ensure new non-road and small 

engine equipment are properly engineered for future commercial fuels. 

Our Response:

Several manufacturers of gasoline nonroad equipment and small engines have 

commented in support of harmonization with CARB’s adoption of an E10 test fuel for their 

products. However, in discussions during the development of the rule, a number of 

manufacturers raised concerns to EPA about the level of ethanol in the new fuel, the cost of 

recertifying emission families on the new fuel, the impact on nationwide product offerings, and 

the cost impact of complying with the existing standards on the new test fuel. While engines in 

some of these categories employ levels of technology similar to light-duty vehicles and trucks, 

the vast majority have much simpler designs, with many of the engines being carbureted with no 

electronic controls. As a result, emissions from these engines are potentially much more 

sensitive to changes in fuel quality.

While EPA believes it is important that the test fuel for nonroad equipment and small 

engines reflects real-world fuel qualities, we have elected to defer moving forward at this time 
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with a change to test fuel for those products. It is important to better understand the effects of 

test fuel specifications on the wide range of engines, vehicles, equipment and fuel system 

components covered. This includes impacts on the levels of the emissions standards as well as 

other issues raised by the manufacturers. EPA plans to explore such a change in a separate, 

future action.

4.5.6. Consideration of CNG and LPG Emissions Test Fuels

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

In the NPRM Preamble, EPA requests comment on the appropriateness of changing 40 C.F.R. 

§86.113 to reference 40 C.F.R. Part 1065 for both natural gas and LPG test fuels. EPA further 

requests comment on amending these specifications to better reflect in-use fuel characteristics, 

and in particular on the appropriateness of aligning the sulfur specifications with those that apply 

for gasoline test fuel. Changing the sulfur specifications would depend on establishing that the 

new specification is consistent with the range of properties expected from in-use fuels (31). 

Automakers agree with EPA that Sec. 86.113 should reference 40 C.F.R. Part 1065 for both 

natural gas and LPG test fuels. For ease of comparison, we have included the two tables, one for 

CNG and one for LPG. From “left to right” each table shows the specified fuel parameters of 

interest, summaries of new final California LEV III and proposed EPA emissions cert fuel 

standards, and then a brief summary of U.S. marketplace fuel quality (32). 

In general, we support the proposed Tier 3 CNG and LPG certification fuel standards... 

Additionally, for CNG, the dissolved Oxygen content should be raised slightly, to 0.5 mole %, to 

better represent the recent market survey results. Particularly for LPG in-use vehicle operation, it 

can be seen that the surveyed marketplace LPG fuel does not follow the total sulfur, reactive 

sulfur (e.g., hydrogen sulfide), water content, and hydrocarbon residues detailed in the proposed 

Tier 3 certification fuel specification. 

U.S. CNG and LPG industries are at the front end of what appears to be the start of a long term 

growth trend, so it is an appropriate time to establish market and test fuel standards, including for 

sulfur. 

Recommendations:

- Current alternative test fuel regulations should be revised, as noted above. 

- EPA should implement our recommended specifications for E85, CNG and LPG detailed 

above. [This comment is also found in section 4.5.2. of this comment summary regarding FFV 

(“E85”) emissions test fuel.] [EPA-HQ-OAR-2011-0135-4461-A1, p. 64, The suggested detailed 

CNG and LPG test fuel specifications are location on pages 62 and 63 of the comment 

document] 
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31 - 78 Fed. Reg. 29908 (May 21, 2013).

32 - U.S. CNG and LPG Market Quality Surveys, SGS Labs, Germany, SGS Group Geneva, Switzerland

Organization:American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

EPA seeks comment on the inclusion of sulfur standards for the test fuel used in natural gas 

engines and certifying liquefied petroleum gas (LPG) vehicles. EPA is also seeking comment on 

the appropriateness of aligning the sulfur specifications with those that apply for gasoline test 

fuel (LPG test fuel sulfur levels are at 80 ppm max for heavy-duty highway engines and for 

nonroad engines). The changes would also need to be consistent with in-use fuels. Lacking any 

data from the in-use distribution system, we don’t see how EPA can make changes to either of 

these test fuel standards at this time.

Organization: National Propane Gas Association (NPGA)

EPA also requested comment on LPG emissions test fuel. Specifically, the Agency seeks input 

on the appropriateness of revising 40 CFR 86.113 to reference 40 CFR 1065.720, which includes 

an 80 ppm maximum sulfur specification for heavy duty highway engines and non-road 

engines.5 Given that this is already a requirement and that we are unaware of any issues 

associated with this sulfur level for test fuel, NPGA would not object to this change. 

Organization: NGVAmerica

The proposal requests comment on whether natural gas should have to meet an in-use standard as 

well as a test fuel standard. EPA regulations currently include test fuel standards for natural gas 

but do not include any controls on sulfur levels.

Based on the foregoing and as explained here, it would be premature to establish test-fuel 

specifications or in-use specifications for natural gas sulfur levels.

Organization: Robert Bosch GmbH, Gasoline Systems, Germany

The best approach would be a standardization on a basis of the actual CEN standardization for 

CNG fuel in Europe. 

Organization: General Motors LLC (GM)

GM fully supports the Alliance/Global comments on both E85 and CNG/LPG certification fuels. 

Our Response:

As discussed at proposal, there are currently no sulfur specifications for the test fuel used 

for certifying natural gas (CNG) vehicles. There is also no sulfur specification in §86.113 for the 

test fuel used for certifying liquefied petroleum gas (LPG) light duty vehicles. The LPG 

certification test fuel for heavy-duty highway engines and for nonroad engines in 40 CFR 
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§1065.720 includes an 80 ppm maximum sulfur specification. We requested comment on the 

appropriateness of amending §86.113 to reference 40 CFR part 1065 for all natural gas and LPG 

test fuels. We further requested comment on amending these specifications to better reflect inuse fuel characteristics, and in particular on the appropriateness of aligning the sulfur 

specifications with those that apply for gasoline test fuel. We noted that revising the sulfur 

specifications would depend on establishing that the new specification is consistent with the 

range of properties expected from in-use fuels.

As discussed in Chapter 5.7.2. of this Summary and Analysis of Comments document and in 

Section V.J. of the preamble to the Tier 3 FRM, additional time is needed for EPA to work with 

industry to collect data on current CNG/LPG sulfur content, to determine whether additional 

control of in-use CNG/LPG sulfur content is needed, and to evaluate the feasibility and costs 

associated with potential additional sulfur controls. Therefore, we are deferring finalizing in-use 

quality and certification test fuel specifications for CNG and LPG.

4.6 Small Business Provisions

4.6.1. Lead Time and Standards

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global Automakers):

EPA proposed that small volume manufacturers (SVMs), defined as manufacturers with average 

annual USA sales of 5,000 units or less, would be allowed a delayed start date for the proposed 

Tier 3 standards. SVMs would continue to meet the current tailpipe, evaporative and refueling 

emissions standards through MY 2021. Then in MY 2022, EPA proposes to require SVMs to 

meet the same FTP fleet average as other manufacturers, as well as use the new certification fuel 

and meeting the other Tier 3 requirements (i.e. SFTP, evaporative emissions, etc.), ultimately 

requiring compliance with the 30 milligrams per mile (mg/mi) fleet average in MY 2025. EPA 

would, however, also provide hardship relief on a case-by-case basis for SVMs.

EPA’s proposal generally follows the Agency’s past practice of allowing SVMs more lead time 

to comply (because of the need for additional flexibility) but requiring SVMs to ultimately meet 

the same standards as other manufacturers. This requirement ensures that SVMs are held to the 

same technological requirements as large manufacturers. However, there is a flaw in this 

argument, which is created by the current regulatory framework of fleet average emissions 

standards, as compared to historical standards. The use of fleet average emissions standards 

emerged when EPA adopted the Tier 2 fleet averaging approach for oxides of nitrogen (NOx) 

emissions. Prior to Tier 2, all vehicles produced in a particular model year had to meet the same 

NOx emissions standards. Starting with Tier 2, manufacturers were allowed to design individual 

models to meet one of several emissions bins, each of which had varying NOx emissions values; 

however, the weighted average mix of vehicles produced in a particular model year had to meet a 

declining NOx fleet average year by year.
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So a large manufacturer could produce a high performance, luxury model and certify it to a 

higher emission bin and offset this model with sales of other lower emitting models. On the other 

hand, a SVM, which only has limited models (in some cases, only one model) primarily sold in 

niche markets, does not have other lower emitting models to use for averaging. As EPA 

recognized in the proposal, “Small manufacturers that typically do not have more than one or 

two emission families generally cannot use averaging to the same extent because of their limited 

product offerings” (78 Fed. Reg. 29915). Consequently, the use of fleet average standards 

penalizes SVMs by holding them to higher level of technology than large manufacturers that 

produce the same types of vehicles. Under the proposed Tier 3 standards, EPA is expanding the 

use of fleet average standards to include both NOx and tailpipe hydrocarbons (NMOG+NOx), 

thus putting SVMs in even further jeopardy.

Another aspect of the Tier 3 proposal is that manufacturers, including SVMs, are allowed to 

comply using an approach based on credits banking and trading. Thus, an SVM could 

accumulate and bank credits that could then be used, if needed, in future years for compliance 

purposes. Additionally, SVMs could purchase another manufacturer’s excess credits, if available, 

for compliance purposes. While these types of credits options have been available under EPA 

regulations, it is our understanding that for criteria emissions, there has been very little, if any, 

trading of credits among manufacturers. Some believe that the credits trading market may 

become more robust in the future; however, today this can only be based on speculation. The 

fundamental problem remains that, in a competitive market such as the auto industry, 

manufacturers do not have much incentive to make credits (which they may need in the future) 

available to competitors nor do they wish to rely on the possible availability of credits from 

competitors as a regulatory compliance strategy.

Furthermore, the demands on SVMs should be balanced against their environmental footprint. 

SVMs’ vehicles are typically driven less per year, as well as over their lifetime, compared to 

other vehicles, resulting in lower overall emissions. Plus due to the limited sales of these 

vehicles, there are far less of these vehicles in the fleet. For example, a composite fleet of SVM 

vehicles (5,000) driven 5,000 miles per year at a fleet average standard of 51 mg/mi would result 

in approximately 1.4 tons of NMOG+NOx in one year.

footnote: According to Polk data, less than 4,000 new units were registered in 

combination for Aston Martin, Ferrari, Lotus, and McLaren in calendar year 2012.

Company data suggests that average miles driven is less than 5,000 per year, on average. 

footnote: For example, McLaren Mercedes SLR showed that for a sample of over 1000 

vehicle between one and three years old, the annual VMT was 1,360. Aston Martin 

estimated that worldwide average VMT of their vehicles since 2004 is 4,500 miles per 

year, and Lotus used a range a 4,500 to 7,000 miles per year based on 200 units in 

warranty.

The remaining fleet of vehicles (14.8 million) certified to an average of 30 mg/mi and driven an 

average of 13,446 miles per year would result in approximately 6,580 tons of NMOG+NOx. The 

difference between the two grows when considering the lifetime vehicle miles traveled by 

SVMs’ vehicles compared to the rest of the light-duty vehicle fleet; SVMs’ vehicles typically do 
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not exceed 60,000 miles over the entire life of the vehicle, even though they will be certified for 

150,000 miles of use under the Tier 3 standards. The resulting impact of SVMs fleets on air 

quality is insignificant in comparison to that of the rest of the fleet.

In light of these considerations, while we support the initial relief proposed for SVMs through 

MY 2021 and the hardship relief, we believe that EPA should provide additional lead time and 

flexibility in MY 2022 and beyond for SVMs. 

EPA continually states throughout the proposal that their main goal is to create a harmonized 

program with ARB. Yet, EPA’s proposed standards for SVMs do not align with ARB’s 

requirements and would result in more stringent requirements. In its final Low Emission Vehicle 

(LEV III) rule, ARB required that SVMs meet a fleet average of 125 mg/mi in MY 2022-2024 

and 70 mg/mi in MY 2025 and beyond. We recommend that EPA align with ARB’s 

requirements for SVMs for MY 2022-2024 to meet EPA’s stated goal of harmonization and 

provide the necessary lead time flexibility that SVMs need to comply with the Tier 3 regulations.

Furthermore, we believe that additional relief in MY 2025 is appropriate. We understand that the 

SVMs do not believe that they can meet the 30 mg/mi fleet average in MY 2025, but, in 

combination with the additional lead time and the flexibility in MY 2022-2024 (125 mg/mi fleet 

average), they believe that they can meet a fleet average lower than 70 mg/mi in MY 2025.

Therefore, we support a fleet average of 51 mg/mi in MY 2025 and beyond for SVMs; this 

level equates to the industry fleet average in MY 2022.

Recommendation: We recommend that EPA revise the requirements for SVMs according to the 

following: In MY 2022-2024, harmonize with ARB’s LEV III SVM requirements of a fleet 

average of 125 mg/mi. In MY 2025 and beyond, adopt a fleet average of 51 mg/mi for SVMs.

Aston Martin Lagonda Ltd:

EPA have proposed that SVMs would enter the Tier 3 proposal for NMOG+NOx at 51mg/mi in 

2022MY, then follow the slope through the following model years to 30mg/mi at 2025MY. 

The NMOG+NOx standard decreasing year on year does not fundamentally work for SVMs with 

their limited test groups and model ranges. It would effectively incur additional testing or early 

compliance with lower standards than is necessary, mainly due to product lifecycle timings. For 

example it may become necessary to certify to the proposed 2022MY 51mg/mi NMOG+NOx 

requirement as early as 2018MY based on current program plans. This could reasonably be seen 

as unfair.

We would propose that, as a minimum, 125mg/mi applies up to 2021MY, followed by 51mg/mi 

from 2022MY onwards. Preferably, the possibility of the temporary Small Business Provision of 

125mg/mi applying all the way to 2024MY would allow for even greater certification timing 

flexibility.
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During the Tier 3 and LEV III formulation periods Aston Martin, Mclaren and Lotus jointly 

urged EPA and CARB to adopt less stringent standards for SVMs based on our inherently 

limited fleet averaging capabilities. CARB understood this thinking and adopted a 70mg/mi 

NMOG+NOx 2025MY SVM standard. EPA has ignored the opportunity to harmonise with 

CARB in this ruling despite the fact that EPA always stated that this was their goal.

EPA made the assumption that SVMs would have ready access to technologies by 2022MY to 

enable them to meet a 30mg/mi NMOG+NOx fleet average by 2025MY. The demonstration of 

capability by the large volume manufacturers does not automatically mean that those same 

technological enablers are available to SVMs in the given timeframe. It is therefore unreasonable 

to base a rule on an assumption of this nature.

Within the Small Business Provision wording, EPA have acknowledged the CARB flexibilities 

for SVMs and have requested comment on a relaxed standard proposal extending from 2022MY 

(the entry point onto the slope for SVMs) thru 2024MY that is based on a 125mg/mi 

NMOG+NOx FTP standard. Aston Martin fully supports this flexibility.

To clarify, Aston Martin would find the 2022 to 2025MY slope fleet average almost impossible 

to meet. As a manufacturer with one or two test groups the slope based fleet average starting in 

2022MY would effectively push us to meet the 2025MY 30mg/mi standard as early as 2022MY 

in order that we do not incur burdensome extra testing of vehicles already certified for 2022MY. 

There are many theoretical scenarios with regard to meeting a certain standard at a particular MY 

but typically as an SVM we would have to treat a fleet average as a cap standard thereby 

ensuring that all vehicles sold within either of our two test groups do not adversely contribute to 

that fleet average requirement. As we have noted on a number of occasions previously the fleet 

average nature of any criteria emissions standard is fine if you have many model lines, and 

therefore test groups, over which to average, but SVMs generally have a (very) limited model 

range leading to the fleet average becoming a cap standard. Additionally SVMs do not have the 

capability to manipulate sales in order to meet the fleet average requirements and are reliant 

upon sales and marketing strategies to gain sales of any and every model in their fleet without 

recourse to sales manipulation.

Alternatively EPA should harmonise with the CARB SVM standard, again with a midterm 

review to determine capability to meet a later, more stringent, standard.

Aston Martin still feels strongly about meeting the 30mg/mi NMOG+NOx standard from 

2025MY. We would propose that SVMs are asked to meet a final 51mg/mi standard from 

2025MY with a midterm review of capability with the individual SVMs in the 2022MY 

timeframe to establish the possibility of meeting a 30mg/mi NMOG+NOx standard.

Aston Martin would propose that SVMs are only held to a 51mg/mi NMOG+NOx standard that 

is applicable from 2022MY onwards and additionally that there is a midterm review of capability 

to meet a more stringent standard after 2025MY.

There is a general understanding that due to the small number of vehicles sold by SVMs and the 

low level of annual mileage accumulation by those vehicles their contribution to fleet criteria 
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emissions levels is de minimis. This fact should allow for a more lenient standard to be 

promulgated without it being viewed as contentious. 

California Air Resources Board (CARB):

California has traditionally provided relief to Small Volume Manufacturers (SVM) (primarily 

producers of high performance vehicles), recognizing that they are at a competitive disadvantage 

with larger manufacturers in terms of both investment and engineering resources. In addition, 

they must compete with full line manufacturers who are able to offset the emissions of their low 

volume high performance vehicles with higher volume, lower emission vehicles. For these 

reasons, LEV III provides slightly less stringent emission standards for SVMs.

Unlike LEV III, Tier 3 requires SVMs to defer compliance with the Tier 3 fleet average 

standards until 2022. The Notice of Proposed Rulemaking (NPRM) requests comment on this 

and an alternative requirement that matches LEV III requirements through 2024 and then 

requires that SVMs meet Tier 3 fleet average requirements in 2025. Since harmonization of 

SVM requirements will allow these manufacturers to certify the same vehicle to both programs, 

CARB recommends that U.S. EPA consider finalizing the alternative requirement by matching 

Tier 3 requirements with LEV III through 2024. Since Tier 3 allows SVMs to apply for hardship 

relief under certain conditions, thereby addressing their concerns on competing with full line 

manufacturers, CARB will review the Tier 3 SVM requirements when finalized and determine 

whether alignment between LEV III and Tier 3 requirements for SVMs beginning in 2025 is 

appropriate. 

Light-Duty NMOG+NOx Certification Options:

The LEV III program sets forth a separate option for certifying light-duty vehicles to the SFTP 

NMOG+NOx standards, primarily to accommodate small volume manufacturer. While the 

proposed Tier 3 program does not include an equivalent option, alignment between the two 

programs is not necessary because Tier 3 would accommodate small volume manufacturers 

through a different mechanism. Specifically, Tier 3 would delay SFTP compliance for small 

volume manufacturers until model year 2022. Accordingly, CARB does not intend to propose 

any changes to the LEV Ill program for this issue. 

Ferrari:

Ferrari has built its reputation in the market segment in which we compete on production of 

vehicles with key attributes—excellent power, superior handling, hand craftsmanship, cutting 

edge to classic body design, signature engine sound and overall superior quality. This is the 

DNA of all Ferrari vehicles, and these factors remain key to Ferrari’s continued success in the 

ultra-competitive, low-volume market segment in which we operate. Ferrari must design and 

build vehicles that prospective owners aspire to purchase. Without the passion for motoring that 

is built into every Ferrari vehicle, Ferrari would be “just another vehicle manufacturer.” The key 

to Ferrari’s future success is to continue to design and build vehicles with the DNA that has 

made Ferrari a vehicle people aspire to own and drive. 
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In addition, as Ferrari has previously noted in other EPA rulemakings and likely due to the DNA 

of our vehicles, these are not driven to the same extent as other manufacturers’ vehicles. For 

example, it is exceptionally rare for a Ferrari to be driven for even 100,000 miles; indeed, an 

exceedingly small number of vehicles, if any, would ever reach the full useful life of 150,000 

miles. Typically, the average Ferrari owner will drive the vehicle for 3000-4000 miles per year.

It is with both the Ferrari DNA and the very low mileage of our vehicles in mind that Ferrari 

offers the technical and policy comments and suggestions below.

EPA has proposed that SVMs (manufacturers with average annual USA sales of 5,000 units or 

less) be permitted to delay meeting the proposed Tier 3 emission standards. During the period up 

to and including 2021 MY, SVMs would have to meet current emission standards. During the 

period of MY 2022-2024 EPA has indicated that a more stringent set of standards would apply. 

Under the proposal, in 2025 MY, SVMs would be required to meet the same standards as large 

volume manufacturers – 30mg/mi of NMOG+NOx.

The following comments are made supposing that EPA will treat the operationally-independent 

manufacturers SVMs in the same way as other SVMs. As noted above, if EPA does not finalize a 

provision that would treat operationally-independent SVMs similarly to how such manufacturers 

are addressed for purposes of the GHG standards, then Ferrari will submit additional comments 

explaining the very different impact this approach would have on our ability to meet Tier 3 

standards.

Taking into account the technologies today available on the market, Ferrari has determined that 

the fleet standards of 51 mg/mi of NMOG+NOx in 2021 MY and of 30 mg/mi in 2025 MY are 

not technically feasible without affecting the Ferrari DNA.

The current technology of catalyst systems and relative wash-coating, even in combination with 

higher loading of precious metals (200-250 g/ft3) could not guarantee our vehicles’ compliance 

with the fleet standards required during the MY 2022-2024 period. The only possible solution 

could be a closed coupled warm-up catalyst and a main catalyst both with a high cells density 

(600-800 cells/inch2), but this will affect performance, sounds and, in general, the typical overall 

Ferrari engine characteristics.

Moreover, the reduction of exhaust emissions would require the development of a complex OBD 

system, able to detect any defect of the catalytic converter system by analyzing the increase of 

exhaust emissions in a much lower range.

In conclusion, taking into account Ferrari’s expected status as an operationally-independent 

small-volume manufacturer, the technologies today available on the market and the importance 

of the keeping alive our models’ DNA, Ferrari kindly requests that EPA establish two separate 

fleet standards for SVMs/operationally-independent manufacturer:

- 120 mg/mi of NMOG+NOx in 2022 MY;

- 70 mg/mi of NMOG+NOx in 2025 MY.
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Ferrari, being an operationally-independent SVM, typically does not have more than two engine 

families. Therefore, unlike much larger manufacturers, Ferrari cannot use averaging to reach a 

lower emissions standard due to its limited product offerings. In other words, for an SVM like 

Ferrari, the fleet standard corresponds to the standard for each engine family. Moreover, Ferrari 

models are characterized by a particularly long life cycle (about 7 years for each model). This 

obviously means less capability to renew our fleet over a short period of time. As a result, it is 

absolutely unfeasible for Ferrari to assure compliance with fleet standards on a year-to-year basis 

as the standards become more stringent each model year.

Therefore, Ferrari kindly requests that EPA establish “stair-step” standards for SVMs and 

operationally-independent SVMs that decrease over a longer time period. Ferrari suggests the 

following time frames: 2017-2020 MYs, 2021-2024 MYs, 2025-2030 MYs.

Ferrari is continuously working in order to reduce the emissions in its vehicles. For this reason, 

Ferrari suggests to EPA to reconsider in MYs 2017-2018 the emission standards for the MYs 

2022-2030, by examining at that point in time whether SVMs and Operationally-Independent 

SVMs could in fact meet a fleet standard below 70 mg/mi. Whether SVMs can meet a standard 

below 70mg/mi will largely depend on the availability of new technologies able to reduce 

emissions without affecting Ferrari DNA. Ferrari continues to work diligently toward this goal. 

But at this time, we do not see a way to reach these standards while retaining the characteristics 

that are key to Ferrari’s continued success in the highly-competitive market segment in which we 

operate.

In the LEV III rulemaking, CARB recognized the particular conditions of SVMs (and 

operationally-independent SVMs) and, consequently, defined SVM-specific fleet NMOG+NOx 

standards. Ferrari has determined that the LEV III standards for SVMs are challenging but still 

feasible. Therefore, we strongly support EPA’s harmonization with CARB. 

Lotus Cars Ltd.:

Vehicle Services Consulting, Inc. (VSCI), who advises Lotus on small volume manufacturer 

matters relating to safety and emissions issues, has prepared and submitted comments regarding 

this proposed rule. Lotus fully endorses these comments.

McLaren Automotive Limited:

For manufacturers with limited product lines where fleet averaging is not possible, the proposed 

30mg/mi target from MY 2025 is not a fleet average limit but effectively a minimum 

requirement, hence the flexibility of fleet averaging afforded to Large Volume Manufacturers is 

not available to Small Volume Manufacturers (SVMs).

There is no confidence to date that the 30mg/mi minimum requirement can be met without 

jeopardising high performance characteristics of McLaren products.

There is no apparent reason for EPA to deal with SVMs differently from CARB. 
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Background:

EPA identifies Small Volume Manufacturers (SVMs) as those with average annual nationwide 

sales of 5,000 units or less on the three year average of actual nationwide sales for MYs 2012-

2014.

In the NPRM EPA allow SVMs the following flexibilities. 

- Postpone compliance with the standards and other Tier 3 requirements, including use of the 

proposed new certification test fuel, until model year 2022.

- Apply, under the hardship provisions, for additional time to meet the 100 percent phase-in 

requirements for exhaust and evaporative emissions.

- Use of assigned deterioration factors.

- Delay using the new test fuel until model year 2022.

For model year 2022 and later, Small Volume Manufacturers would be subject to the same Tier 3 

exhaust and evaporative requirements as other manufacturers, including moving to the declining 

FTP fleet average NMOG+NOX curve and complying with the fully phased-in standard of 30 

mg/mi, as well as certifying on E15 test fuel.

EPA also propose that “in light of the CARB Board-approved implementation schedule for small 

manufacturers described above, we also request comment on an option that would not provide a 

permanent relaxed standard for small manufacturers, but would provide a temporary relaxed 

standard matching the California standard from model year 2022 through 2024. This option 

would apply to the Tier 3 exhaust emission standards starting in 2022, except that a relaxed 

NMOG+NOX standard of 125 mg/mi would apply in model years 2020-2024 for FTP testing. 

For model years 2025 and later, the standard would be the same as for all other manufacturers, or 

30 mg/mi. Under this option, small manufacturers would have to take some action to reduce 

emissions in 2022 and could postpone meeting fully phased-in Tier 3 standards until 2025.” 

The above can be briefly summarised as follows.

- A business with annual nationwide sales of 5,000 units or less (calculated on the three year 

average of actual nationwide sales for MYs 2012-2014) will be allowed to comply with the 

current standards during the period to and including MY 2021.

- During the period MY 2022-2024 EPA may apply more stringent standards.

- In MY 2025 SVMs would be required to meet the same standards as Large Volume 

Manufacturers.

With regard to the above, McLaren Automotive Ltd. appreciate EPA effort to introduce 

flexibility for small volume manufacturers in their NPRM regarding Tier 3 standards however, 

we note that a number of concerns have not been addressed by EPA, to date. We believe that 

EPA current position is strongly at risk of jeopardising Small Volume Manufacturers business 

and competitiveness in the US market.

Fleet average mechanism unfairness to SVMs:

The limited product ranges of SVMs’ make it impossible for them to make use of the fleet 

average emissions standards applicable to large manufacturers.
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As a consequence of fleet averaging being not feasible for SVMs, McLaren consider that the 

proposed Tier 3 NMOG+NOx fleet average standard places SVMs at a significant disadvantage 

compared to Large Volume Manufacturers (LVMs).

Manufacturers like McLaren will not have possibilities to fleet average their emission results 

hence translating the actual EPA requirement to a fixed standard.

As a consequence, whilst being given the possibility to comply with the proposed standard later 

in time, EPA is denying SVMs the flexibility allowed to the niche vehicles of LVMs that 

compete directly with our products. Such flexibility will allow LVMs to produce niche vehicles 

that do not have to meet what is effectively a criteria emission limit for equivalent products 

produced by SVMs.

The policy issue in connection with the fleet average mechanism is simply one of fairness, since 

LVMs are able to produce niche vehicles using their fleet average but SVMs are not able to do 

the same.

For 30 years EPA has taken the position not to promulgate SVM-specific standards (contrary to 

CARB). The issue now is whether history should take precedence over fairness.

The fairness issue is touched by EPA themselves in The Draft Regulatory Impact Analysis: Tier 

3 Motor Vehicle Emission and Fuel Standards, March 2013, par 1.2 (FTP NMOG+NOX 

Feasibility), EPA clearly recognise that “the proposed new emission requirements include 

stringent NMOG+NOX standards over the FTP that would require new vehicle hardware and 

additional control of gasoline sulphur levels in order to achieve the 30 mg/mi fleet average level 

in 2025. The type of new hardware that would be required would vary depending on the specific 

application and emission challenges.

Smaller vehicles with corresponding smaller engines would generally need less new hardware 

while larger vehicles and other vehicles with larger engines may need additional hardware and 

improvements beyond what would be needed for the smaller vehicles. Additionally, the fleet 

average nature of the standards would allow more challenged vehicles to be offset by vehicles 

that could outperform the required fleet averages.”

Clearly, small volume manufacturers like McLaren will have to face the challenge of engineering 

additional hardware and improvements without taking any advantage of any “fleet average 

nature of the standards”.

In the NPRM, EPA reports their position on a series of comments raised. Citing from the NPRM, 

“during the SBAR Panel process, one small entity representative (SER) recommended that EPA 

adopt relaxed exhaust standards for small manufacturers.

The SER noted that the exhaust emission averaging program being proposed by EPA would 

allow large manufacturers that have many engine families to certify their small, niche products at 

emission levels numerically higher than the standards.
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Small manufacturers that typically do not have more than one or two emission families generally 

cannot use averaging to the same extent because of their limited product offerings. The SER was 

concerned that the high-performance vehicles produced by large manufacturers which they 

compete against would be able to certify at numerically higher levels at less cost than the SER 

would incur.”

Whilst we appreciate the consideration that EPA have shown in reporting these comments, it is

notable that the EPA did not provide any comment with respect to the SER concern that “EPA 

would allow large manufacturers that have many engine families to certify their small, niche 

products at emission levels numerically higher than the standards.” 

McLaren strongly believe that this is a key issue in the extent that it highlights how McLaren 

(and SVMs in general) must compete with niche products from large OEMs that need not 

comply with the same standard limit. This is an unfair situation created by the current Tier 3 

proposal. 

Technological feasibility assessment pending:

As a Small Volume Manufacturer with limited development resources, McLaren must develop a 

high performance product that produces class-leading CO2 emissions, fuel economy and 

driveability.

In general the relatively low sales volumes of SVMs mean that a return on investment must come 

from astute platform engineering and an extended life cycle for the base powertrain.

In EPA comprehensive “Draft Regulatory Impact Analysis: Tier 3 Motor Vehicle Emission and 

Fuel Standards”, main technological aspects for FTP NMOG+NOX have been studied and EPA 

anticipates that “to achieve the proposed NMOG+NOX FTP emissions standards, vehicle 

manufacturers will focus on three areas to reduce emissions:

- reducing the emissions produced by the engine before the catalyst reaches the light-off 

temperature;

- reducing the time required for the catalyst to reach the light-off temperature; and,

- improving the NOX efficiency of the catalyst during warmed-up operation.”

Whilst we appreciate EPA analysis on available and future technologies that will be developed in 

order to meet the new requirements and whilst we understand and share the effort in controlling 

the country’s pollution, we believe that EPA is incorrect in believing “that these standards are 

technologically feasible and can be readily achieved with the additional lead time we are 

proposing as the technology would have already been demonstrated by other manufacturers, in 

some cases on the very same engines used by the small manufacturers.”

Given the inapplicability of fleet averaging to SVMs, the EPA’s assumption that SVMs will be 

able to achieve the 30mg/mi target is incorrect because SVMs cannot rely upon the technology 

demonstrated by other manufacturers. In fact, as stated in previous paragraphs, the Tier 3 

proposal would allow LVMs to produce vehicles with similar characteristics and performance 

but with higher NMOG+NOX emissions than SVMs.
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Independently from LVMs, SVMs are exploring technologies that would enable the Tier 3 

standards to be achieved without compromising the essence of our products and are constantly 

working on assessing the potential of new technologies and innovations that could contribute 

towards achieving future legislative requirements and provide product differentiation in the 

market place.

SVMs like McLaren have already developed their own new engine using optimised 

technological and engineering solutions (Variable Valve Timing (VVT), Secondary Air Injection 

(SAI), electronically controlled twin thermostats, very high precious metal loading on catalysts, 

close-coupled catalyst, etc.).

With reference to the aforementioned EPA Impact assessment, after extensive research, McLaren 

would respectfully suggest that more time is needed to assess the feasibility of the 30mg/mi limit 

which EPA is effectively setting as a minimum requirement for SVMs.

McLaren studies to date show that, although combustion system, emissions and after treatment 

research and development projects are being suitably funded and pursued aggressively by 

McLaren, a technology package that will enable a niche sport car engine to both:

- deliver the 30mg/mi proposed Tier 3 NMOG+NOx emissions requirements; and, 

- meet the very high specific power and low weight requirements demanded by this market 

segment has not yet been identified. 

Conclusions:

McLaren believe that the Tier 3 rulemaking should provide an alternate SVM standard. 

- The proposed 30mg/mi target from MY 2025 is not a fleet average limit but a minimum 

requirement, hence the flexibility of fleet averaging afforded to Large Volume 

Manufacturers is not available to Small Volume Manufacturers

- There is no confidence to date that the 30mg/mi minimum requirement can be met 

without jeopardising high performance characteristics of McLaren products.

- There is no apparent reason for EPA to deal with SVMs differently from CARB

McLaren would therefore suggest that a fair and reasonable Tier 3 SVM solution would be as 

follows.

Appropriate phase-in and interim SVM NMOG+NOx fleet standards

- Model year 2014-2016: 160mg

- Model year 2017-2021: 125mg

- Model year 2022+: 51mg

At this time it is not demonstrably feasible to design a high-performance niche-market 

powertrain to achieve a 30mg/mi NMOG+NOx standard and as such, SVMs must be permitted 

the time to assess the outstanding technical issues.

McLaren recommends that the 51mg/mi standard, consistent with CARB policy, should be set in 

Tier 3 for SVMs. 
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McLaren proposes that time be permitted to allow industry development to demonstrate 

feasibility of meeting standards below 51mg/mi in high performance engines from MY2025 on. 

It is proposed that a review of feasibility to reduce targets below 51mg should be held by 2018. 

Vehicle Services Consulting, Inc (VSCI):

We focus on two key points – That the ‘fleet average’ system is unfair in how it affects SVMs 

compared to the niche carlines of large volume manufacturers (LVMs); and

That to remedy (in part) this inherent unfairness, for SVMs the MY 2022 51mg fleet standard 

should not continue downward to 30mg unless and until there is clear evidence that SVMs – with

their limited model offerings (and hence limited number of test groups) – can in fact attain the 

30mg level. 

EPA has proposed that SVMs — manufacturers with average annual USA sales of less than 

5,000 units – be permitted to delay meeting the proposed Tier 3 emission standards. 2

During the period to and including MY 2021, SVMs would have to meet current Tier 2 emission 

standards.

During the period MY 2022-2024 EPA has indicated that a set of more stringent interim 

standards would apply. 

In MY 2025, SVMs would be required to meet the same standards as large volume 

manufacturers — 30mg of NMOG+NOx. In other words, in MY 2025, a company that sells 25 

cars per year in the US would have to meet the same standards as a company like GM that sells 

2.5 million cars per year in the US.

footnote: Indeed, EPA is not even proposing that businesses which meet the Small Business 

Administration definition of ‘small entity’ would be subject to more lenient requirements. This is 

manifestly unfair.

SVMs have urged EPA to adopt less stringent standards specifically applicable to small volume 

manufacturers — the philosophy that the California Air Resources Board (CARB) has adopted. 

The basis for this SVM request is a key fact which EPA itself has acknowledged – that the 

emission averaging program used by EPA allows large manufacturers, which have many engine 

families, to certify their small, niche products at emission levels numerically higher than the fleet 

standard. SVMs, on the other hand, which typically do not have more than one or two engine 

families, generally cannot use averaging to reach the same result due to their limited product 

offerings. SVMs have therefore been concerned that LVM high-performance vehicles with 

which SVMs compete will be certified at numerically higher emissions levels and at less cost 

than the levels and costs that SVM would face. Indeed, CARB recognized this very issue in 

adopting its LEVIII standards, and promulgated an SVM-specific fleet NMOG+NOx standard. 4

In view of the above, SVMs recommended to EPA that Tier 3 include less stringent, SVMspecific NMOG+NOx standards in order to reach an equitable result for SVMs, while at the 

same time harmonizing with California — a clearly stated goal of EPA. 
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No one disputes that the total number of SVM vehicles per year in the US has an insignificant —

de minmis — impact on US air quality. 

The NPRM’s Small Volume Manufacturer Language:

From the NPRM, it is clear that EPA has not agreed with the SVMs’ suggested approach. 

Although EPA is proposing a delay in Tier 3 requirements as they apply to SVMs, EPA is not 

proposing an SVM-specific fleet standard when the Tier 3 rulemaking phase-in ends. We believe 

that EPA’s decision is insufficient and inequitable. 

EPA believes that the large volume end-of-phase-in standards are technologically feasible for 

SVMs, and that they can be readily achieved with the additional SVM lead time being 

proposed.5 We strongly disagree.

We have not seen hard evidence to support EPA’s conclusion. EPA alleges that by 2022 ‘the 

technology would have already been demonstrated by other manufacturers, in some cases on the 

very same engines used by the small manufacturers’. EPA is therefore assuming that the 

necessary technology will be available to SVMs. But such assumptions are an insufficient 

foundation on which to base a rule’s applicability. Under the Administrative Procedure Act it 

would be impermissibly arbitrary and unreasonable to base the SVM standards on an assumption 

of this magnitude. 

Indeed, what would happen if an SVM used a Tier 2 Bin 5 engine sourced from a large volume 

manufacturer? Under Tier 3, the LVM could continue to use and certify this engine based on the 

LVM’s fleet average. The SVM, however, would be precluded from using the engine under Tier 

3 since the Bin to which the engine was certified would be above the fleet standard. This result is 

simply unjust. 

EPA also notes in the Tier 3 preamble that ‘the compliance costs for many of these [SVM] 

vehicles, even if higher on an absolute basis, may still be lower on a relative basis given the 

higher average cost of the vehicles’. But this remark begs the question, since there are niche 

products of large manufacturing groups that indeed compete with SVM products and are sold at 

similar prices to SVM vehicles.

In short:

We strongly believe that fairness requires that small manufacturers be allowed to meet less 

stringent, SVM-specific, NMOG+NOx exhaust emission standards over the long term, as 

reflected in the LEVIII rules from CARB. We support EPA’s harmonizing with CARB.

footnote: In view of EPA’s firm stance against harmonization, however, as discussed below, we 

propose herein an SVM solution that diverges from CARB, notwithstanding our firm support 

both for CARB’s decision and for harmonization

But the heart of the problem remains that EPA seeks to compel SVMs to meet the fully phasedin large volume Tier 3 NMOG+NOx fleet standard for model years post 2022 (and specifically 

the MY 2025 standard of 30 mg/mi). This is neither fair nor feasible.

footnote: EPA has asked SVMs to provide evidence of infeasibility. But few people would argue 

that it is easy – or even possible – to prove a negative.
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EPA’s justification for only proposing extra lead-time for SVMs — even in the face CARB 

deciding otherwise — has been that extra lead-time has always been EPA’s policy for SVMs and 

has worked adequately under Tier 2. But this response is hollow — amounting to ‘we have 

always done things this way so we will continue to do them this way.’ EPA’s rationale overlooks 

how, as standards become more and more stringent, new flexibilities must be considered.

footnote: Justice Oliver Wendell Homes wrote in ‘The Common Law’ that: ‘The truth is that the 

law is always approaching and never reaching consistency.’

Conclusions:

SVMs would therefore suggest that a fair and reasonable Tier 3 SVM solution would be as 

follows:

1) Appropriate phase-in and interim SVM NMOG+NOx fleet standards

Model year 2014-2016 2017-2021 2022+

 160mg 125mg 51mg

2) We note that, for MY 22 an SVM NMOG+NOx fleet standard of 51 mg would be the 

same as the large volume fleet standard for that year.

3) But under our suggested approach, the SVM standard would remain at 51mg as the 

interim SVM standard, while the large volume standard would continue to tighten down 

to 30mg for MY 2025.

footnote: For small entities, we urge EPA to allow a 125mg standard through MY 2024 and then 

to require the 51mg standard in MY 2025.

4) The above proposal actually brings forward by four years a more stringent (ULEV) SVM 

standard (compared to the NPRM and CARB).

5) The above SVM solution is in reality a leadtime issue. We are not saying that SVMs 

should not be required to meet a 30mg standard. Rather, we are taking issue with WHEN 

SVMs should be so required. We believe that it should be after MY 25 and thus that any 

SVM standard lower than 51mg should be set by a further rulemaking.

6) The SVM longer term issue can be revisited in CY 2017-18 to examine at that point in 

time, whether SVMs could in fact meet a fleet standard below 51 mg in the post MY 

2025 timeframe. 

In closing, we raise the following query: if EPA promulgated the proposed SVM language as a 

final rule, then would not SVMs find themselves in the awkward position of either having to 

accept an EPA conclusion that 30mg is doable in MY 2025 or to challenge immediately the EPA 

rule in order to avoid waiving their right to seek judicial review of the issue? 

Our Response:

As described above, commenters provided a variety of information and a number of 

conclusions drawn from this information in support of our assessment that Tier 3 implementation 

flexibility for small entities is warranted. These commenters include trade associations that 
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represent both large and small manufacturers of motor vehicles. None of the commenters 

opposed our granting such flexibility. 

We received comments from SVMs (but none from non-SVM small businesses subject to 

the Tier 3 vehicle standards) about our specific proposed small entity phase-in provisions, as 

well as from the Alliance of Automobile Manufacturers and the Association of Global 

Automakers, arguing that the proposed phase-in for small entities did not provide adequate lead 

time relief for SVMs, and that the long-term Tier 3 standards for light-duty vehicles are not 

technologically feasible for SVMs. They referred to the ability of large manufacturers to offset 

high emissions from high-performance, luxury models by averaging with their low-emitting 

models, while competing SVM products must be designed to actually achieve low emissions 

while still meeting customers’ performance expectations. The limited production of these SVM 

models can also result in emission control technology suppliers placing a lower priority on SVM 

orders than on those of larger, high-volume manufacturers.

Because of these factors, SVMs suggested that their companies meet a slightly more 

stringent NMOG+NOX standard (125 mg/mi) than what we proposed for SVMs in the early 

years of the program and a permanently relaxed standard of 51 mg/mi beginning in MY 2022. 

Ferrari suggested a compliance schedule for SVMs similar to that of the California LEV III 

program, with either a permanently relaxed standard (matching the California LEV III 70 mg/mi 

long-term standard) or a delay until MY 2030 to meet the primary 30 mg/mi Tier 3 standard 

(when they suggest that SVMs could potentially comply). VSCI suggested that EPA’s long-term 

standard-setting be deferred to a subsequent rulemaking, characterizing it as a leadtime issue—

not a matter of “if” the SVMs should be required to meet a 30 mg/mi standard but of “when”. 

CARB comments supported Tier 3 adoption of its LEV III provisions for SVMs, including the 

long-term 70 mg/mi standard beginning in MY 2025.

After considering the comments, we agree with SVMs that their unique logistical and 

technological challenges, especially in the later years of the primary NMOG+NOx FTP 

standards phase-in schedule, warrant a significant period of relaxed standards for these 

manufacturers. However, we have found no fundamental reason why, given sufficient lead time, 

all manufacturers, regardless of company size and vehicle characteristics, will not be able to 

meet the Tier 3 standards. Thus, we are finalizing an optional program for SVMs, available to 

non-SVM small businesses as well, under which they can choose an alternative 3-stage FTP 

NMOG+NOx fleet average standard phase-in schedule: an initial standard of 125 mg/mi for 

MYs 2017 through 2021, a more stringent standard of 51 mg/mi for MYs 2022 through 2027, 

and the final Tier 3 standard of 30 mg/mi thereafter.

Commenters’ argued against a 30 mg/mi long-term standard for SVMs based on their 

fundamental inability to use emissions averaging to build high performance cars that have 

emissions above the standards over the long run, in contrast to competing large manufacturers 

with high-performance products, who sell many lower-performance vehicles with which to 

average. Commenters also point out that the lack of opportunity for SVMs to average emissions 

is paralleled by the lack of a robust credit trading market in this sector. Manufacturers with 

credits have thus far not been greatly interested in selling them. 
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However, none of the commenters addressed the most recent experience with this issue in 

the Tier 2 program, which phased in several years ago based on a bin and fleet average concept 

that, as pointed out in comments from the Alliance and Global Automakers, is very similar to the 

Tier 3 phase-in concept central to the SVMs’ expressed Tier 3 concerns. In a 2010 review of the 

impacts of the Tier 2 rule on small businesses, performed under Section 610 of the Regulatory 

Flexibility Act, we concluded that the Tier 2 rule needed no revisions at that time to minimize 

impacts on small entities (75 FR 79853, December 20, 2010). No comments from SVMs were 

submitted in the public comment opportunity for that review. We have not received any other 

information or comment that SVMs have become non-competitive in the high-performance car 

market over these years as the result of Tier 2 regulations and the long-standing ability of large 

competitors to gain an advantage through fleet-wide averaging under the Tier 2 program. 

Though we acknowledge additional factors such as differences in the overall economic climate, 

the recent setting of greenhouse gas emissions standards, and the relative stringency of Tier 2 

and Tier 3 standards, this experience under the Tier 2 program bolsters our confidence that, with 

the additional implementation flexibility provided in the final Tier 3 rule, SVMs will be able to 

meet the long-term 30 mg/mi standard by MY 2028 without becoming non-competitive in their 

market segment. 

Ferrari also raised technical concerns with application of the 30 mg/mi standard, arguing 

that the use of a close-coupled warm-up catalyst and main catalyst with 600-800 cells/inch2 cell 

density to meet the standard would affect engine performance and acoustics. McLaren also 

provided technical comments, pointing to progress with variable valve timing, secondary air 

injection, electronically controlled twin thermostats, very high precious metal loading on 

catalysts, and close-coupled catalysts, but suggesting that more time is needed to assess the 

feasibility of the 30 mg/mi limit while maintaining the very high specific power and low weight 

requirements demanded by this market segment, and to develop associated OBD systems. We 

agree that the successful application of these technologies to high-performance vehicles will 

require some time, and have concluded that the additional extension to the phase-in period we 

are adopting for SVM compliance with the final standard in MY 2028 (under the 3-stage 

alternative), coupled with the extension of credit life and availability of hardship relief, 

adequately address the SVMs’ concerns. 

What Commenters Said:

VNG.CO (VNG):

Extended Lead Time: The NPRM proposes extending to SVMs only a special lead time of five 

additional years (until 2022) before they must meet the full Tier 3 exhaust and evaporative 

standards, based on the rationale that small manufacturers have limited resources available for 

developing new designs to comply with new emission standards.

OEMs will also face significant engineering requirements unique to the production of NGVs 

under the proposed rules, and may have similarly limited resources to devote to these 

requirements if the market for NGVs is still relatively small in 2017. One of the chief impacts of 

the Tier 3 program will be to move OEM gasoline vehicles from the use of port fuel injection 
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(PFI) to gasoline direct injection (GDI) technology, which can achieve significantly lower 

emission levels as well as higher fuel economy. Howver, as noted in the NPC Future

Transportation Fuels study, additional investments in research and development and engineering 

will be necessary for OEMs to utilize this technology for gaseous fuels because of several new 

challenges unique to converting vehicles to operate on CNG, including:

- Thermal management of GDI fuel delivery system components such as the high-pressure pump 

and injectors needs to be addressed as a result of no cooling offered to the gasoline injector when 

operating on natural gas.

- Engine oil pumps, nozzles, and coolers may require design changes in order to manage heat 

due to the high combustion chamber temperatures in natural gas mode.

- Adapting base vehicle GDI controls to CNG PFI, and accommodating PFI components in base 

engine GDI architecture.

- Turbocharger designs may need to change in order to achieve a faster response time to 

minimize performance differences between gas.

While it will clearly be necessary for these OEM investments to be made in order to ensure a 

long-term future for NGVs, it is not clear that market growth in the near term will be sufficient to 

justify these investments in time for the 2017 model year. Thus, EPA should also grant OEM 

production of gaseous-fuel small-volume test groups an option for an extended phase-in period 

for the Tier 3 standards identical to that proposed for SVMs. 

Our Response:

We disagree with VNG’s assessment that small-volume test groups of large 

manufacturers should have until 2022 to comply with Tier 3. The technical challenges outlined 

by VNG have to do with converting gasoline vehicles to run reliably and durably on natural gas.

Although these conversion challenges may increase for the new generation of turbocharged GDI 

vehicles, we have no evidence or vehicle manufacturer comments indicating that meeting Tier 3 

standards is significantly more difficult for natural gas vehicles than for gasoline vehicles. We 

are providing some reduction in regulatory burden for small volume test groups in the form of 

assigned deterioration factors, but not because of feasibility concerns. Rather, we believe that 

assigned deterioration factors provide a sufficient alternative to the extensive process of 

developing a unique factor for each low-volume vehicle model. We find no justification to delay 

compliance with Tier 3 standards for larger manufacturers’ low-volume models as requested by 

VNG. We did not receive comments from vehicle manufacturers on this issue raised by VNG. 

4.6.2. Useful Life and Assigned Deterioration Factors

What Commenters Said:

McLaren Automotive Limited

Useful life requirements are unrealistic for SVMs:

EPA is proposing extension of the regulatory useful life to 150,000 miles, from 120,000 miles.
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Data from MP4-12c customers has shown average annual Vehicle Miles Travelled of 4100 

miles. Consequently, it is extremely unlikely that McLaren vehicles will reach 150,000 miles in 

their lifetime.

McLaren believe that lower VMT per annum and over a lifetime, is typical for an SVM produced 

vehicle, as these are niche vehicles bought by enthusiasts and collectors who typically own a 

large number of vehicles.

The combination of low sales volumes and low annual mileage means that the actual pollution 

impact of McLaren vehicles as a proportion of the USA fleet is extremely small.

Consequently, a 150,000 mile useful life for SVM vehicles is unrealistic and such a durability 

requirement would place an excessive liability on SVMs. 

Our Response:

The Tier 3 useful life requirement is 150,000 miles or 15 years, whichever occurs first 

(alternatively 120,000 miles/10 years for vehicles under 6,000 lbs GVWR certified to a 

numerically lower NMOG+NOx standard level). For vehicles driven 4100 average annual miles, 

the Tier 3 useful life would elapse after 15 years, not the 36 years it would take to accumulate 

150,000 miles. We expect that a 15 year vehicle life is not uncommon for such vehicles, and that 

emissions control systems designed to perform well for this period are feasible in the Tier 3 

timeframe. Key elements of emissions control design that are more prone to mileage-based 

degradation than to time-based degradation, such as irreversible catalyst poisoning, would be 

more challenging for higher annual mileage vehicles than for vehicles like those built by 

McLaren that, at 4100 average annual miles, would surpass their 15 year useful life before 

accumulating 62,000 miles. We believe any remaining concerns SVMs may have about 

establishing durability for EPA certification will be mitigated by our allowing the use of EPAassigned deterioration factors and, where useful, pre-certification discussion between the 

manufacturer and EPA regarding useful life durability demonstration requirements. McLaren 

did not provide any specific technical information to support its statement about excessive 

liability.

What Commenters Said:

Aston Martin Lagonda Ltd:

We would welcome the opportunity to use EPA assigned DFs [deterioration factors] as an 

alternative to manufacturer DFs but must reiterate the need for those DFs to be kept up to date 

with LVM capabilities in order for them to be useful to SVMs. EPA have indicated that they 

recognize this, can it be confirmed that EPA assigned DFs will be regularly updated? 

Our Response:
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In response to Aston Martin Lagonda’s request that the Agency confirm that it will keep 

these factors up to date as durability data accumulates, we can state that we are committed to 

periodically updating and publishing these assigned deterioration factors.

4.6.3. Reduced Testing Burden

What Commenters Said:

VNG.CO (VNG):

Reduced OBD Testing Requirements – Today: Current EPA rules allow alternative fuel 

conversion SVMs to meet much less stringent OBD requirements than OEMs certifying small 

volume test groups, with as few as four tests of major diagnostic monitors (including fuel trim 

lean & rich, catalyst deterioration, engine misfire, and oxygen sensor) instead of the many more 

typically required for OEM certification. As illustrated above, the NPC Future Transportation

Fuels report notes that “certification, OBD, aftertreatment and calibration” are a significant 

source of per-vehicle incremental costs for current OEM NGV production. This is particularly 

the case for pickup trucks, where it is the single largest cost component at about $4,500 per 

vehicle, or nearly 40% of the total incremental cost.

Harmonizing OEM small vehicle test group OBD testing procedures with the reduced OBD

testing requirements for alternative fuel converters is consistent with the ‘level playing field’

provided in most other respects between these categories of vehicles, and represents a major 

opportunity to reduce NGV incremental costs for consumers without sacrificing the efficacy of 

the certification process.

footnote: Existing EPA regulations (40 CFR 86.1806–01) already afford flexibility in OBD 

testing requirements and allow EPA to reduce them if requested to do so by the applicant, 

particularly in the case of alternative fuel vehicles. EPA should encourage both SVM converters 

and OEMs certifying NGVs in small-volume test groups to request and utilize these reduced 

OBD requirements. 

Our Response:

We proposed to apply CARB’s OBD requirements to Tier 3 vehicles, with an exception 

for small alternative fuel vehicle converters to instead meet our existing OBD requirements (40 

CFR 86.1806-05). VNG objected that the proposed exception disadvantages larger 

manufacturers and should be made equally available to all vehicle manufacturers’ small volume 

test groups. We expect that larger manufacturers that produce alternative fuel vehicles will be

familiar with CARB’s OBD requirements and well-positioned to implement these requirements 

in Tier 3. We note that larger OEMs themselves did not request an extension of this provision to 

themselves. We are finalizing the exception to the Tier 3 OBD requirements as proposed. 

However, as discussed in Chapter 4.4, we are willing to consider reduced OBD requirements for 

small volume test groups of OEMs (perhaps on a transitional or interim basis) in the future, 

although we cannot at this time commit to applying the changes under consideration in 

California.
Tier 3 Summary and Analysis of Comments

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What Commenters Said:

Aston Martin Lagonda Ltd:

We accept the rationale behind the small business waiver for PM testing, but of course the 

statement of compliance for PM standards also requires some knowledge of the capability of the 

EDV (and indeed all engines/permutations contained in that test group) for each test group which 

in turn drives the need for testing! 

Our Response:

We agree that a manufacturer’s statement of compliance with the PM standard could 

depend on testing to provide confidence in its validity. It is not our intent to prescribe or limit 

actions a manufacturer considers necessary to gain this confidence. Nevertheless, we believe the 

waiver from certification testing will reduce burden for small businesses.

4.6.4. Hardship Relief

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global Automakers):

In light of these considerations [detailed above in Chapter 4.6.1], while we support the initial 

relief proposed for SVMs through MY 2021 and the hardship relief, we believe that EPA should 

provide additional lead time and flexibility in MY 2022 and beyond for SVMs. 

Aston Martin Lagonda Ltd:

Aston Martin appreciates the Hardship provision being proposed and the flexibilities contained 

in the wording. If we are talking about more time to comply as a hardship provision I would 

point EPA towards the temporary relaxed NMOG+NOx standard noted in the NPRM and 

commented on in the first paragraph above, and the fact that this provision alone would give 

SVMs added flexibility to accommodate the need to meet the 30mg/mi standard by 2025MY. 

Additionally (and also as noted above) I believe that SVMs would appreciate a midterm review 

of capability that would allow them to give EPA adequate notice of any hardship requirement. 

Ferrari:

Ferrari faces significant technical challenges in meeting the 30mg/mile standard. Ferrari 

produces only two engine families, meaning that the ability to average emissions and offset an 

engine family with higher emissions is extremely limited, particularly when compared to large 

volume manufacturers. In addition, Ferrari must continue to produce vehicles that still retain the 

Ferrari DNA and meet customer expectations for performance.
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To reflect the unique challenges faced by a small volume manufacturer producing highperformance vehicles under the proposed Tier 3 NMOG+NOx standards, Ferrari proposes 

revised regulatory language that would provide compliance flexibility to small volume 

manufacturers facing technical hardship. As currently written, the economic hardship provisions 

do not adequately address the technical issues we face. Therefore, Ferrari suggests that EPA 

establish a similar but separate provision allowing a small volume manufacturer to request an 

extended compliance deadline for the NMOG+NOx fleet average standard beginning in MY2028 

if the manufacturer demonstrates technical—rather than economic—hardship. 

Lotus Cars Ltd.:

Vehicle Services Consulting, Inc. (VSCI), who advises Lotus on small volume manufacturer

matters relating to safety and emissions issues, has prepared and submitted comments regarding

this proposed rule. Lotus fully endorses these comments.

Vehicle Services Consulting, Inc (VSCI):

We commend EPA for proposing an SVM hardship provision which will allow SVMs to apply 

for additional lead-time on a case-by-case basis. 

footnote: EPA has proposed a hardship provision for SVMs — see reference in footnote 5 above. 

Under the hardship provision, small businesses would be allowed to apply for additional time to 

meet the 100 percent phase-in requirements for exhaust and evaporative emissions. All hardship 

requests would be subject to EPA review and approval. Petitions for hardship relief would need to 

be made in writing and submitted before the earliest date of potential noncompliance. The request 

would need to identify how much extra time is requested. It must also include evidence that the 

noncompliance would occur despite the manufacturer’s best efforts to comply, and must contain 

evidence that severe economic hardship would be faced by the company if the relief were not 

granted. Thus, the hardship provision could provide the opportunity for small businesses to obtain 

more time to comply with the new Tier 3 standards. While the existing hardship provisions in part 

1068 limit the extra time that can be requested to 1 year, EPA is proposing that such limit not be 

included in the Tier 3 rule. SVMs support this proposal. However, we point out that while a 

hardship provision is a significant step in the direction of equity and fairness, the hardship 

provision by itself does not afford SVMs a sufficient basis on which to reasonably develop 

business and engineering plans beyond 2021.

Our Response:

Commenters generally supported the proposed provisions for hardship relief, within the 

context of a revised approach to small volume manufacturer lead time, discussed in Chapter

4.6.1. In response to Ferrari’s additional request to expand the proposed hardship relief 

provision, we believe the hardship provision already addresses Ferrari’s concern over noneconomic technical hardship. The economic case we are requiring, involving a showing of 

“severe economic hardship” will not be difficult for an SVM having problems certifying to Tier 

3 standards to make, considering the limited product offerings of the SVMs. Inability to certify 

and therefore sell vehicles would be almost certain to create a severe economic hardship.
Tier 3 Summary and Analysis of Comments

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4.6.5. Applicability of Flexibilities

What Commenters Said:

Advanced Biofuels USA (ABFUSA):

While nothing in these regulations should throw up unneeded barriers to true low-volume 

manufacturers, EPA should proceed cautiously on the determination of what is a “low-volume” 

manufacturer. There are three circumstances that need to be considered.

1. While a manufacturer listed as a US company may fall in the <5,000 or 5,001-15,000 

US vehicles sold category it’s worldwide sales total may well exceed that. Aston Martin 

most probably falls in that category.

2. While a manufacturer listed as a US company may fall in the <5,000 or 5,001-15,000 

US vehicles sold category it is actually a part of a larger motor vehicle company that sells 

many more vehicles that 5,000 or 15,000 worldwide. Ferrari USA, which is part of Fiat, 

Porsche USA, which is part of Volkswagen/Audi, and Jaguar USA, which is part of Tata 

all fall in that category.

3. While a manufacturer listed as a US company may fall in the <5,000 or 5,001-15,000 

US vehicles sold category it is actually a part of a larger motor vehicle company that has 

a business plan to greatly increase US sales above the initial “beachhead” number of a 

few thousand in a short timeframe.

In each of these cases, especially number 3, EPA would run the risk of approving a once lowvolume vehicle that turned into a US market 250,000/year seller two or three years later without 

adequate long-term performance data that could predict consumer in-use issues including 

potential recalls. 

California Air Resources Board (CARB):

Independent operational manufacturers are a subset of small volume manufacturers. These 

manufacturers would qualify for small volume manufacturer status, except they are owned by a 

larger manufacturer and their sales are currently aggregated with the larger manufacturer when 

determining emission compliance. Both the California and federal greenhouse gas programs 

allow these manufacturers to meets small volume manufacturer emission requirements if they 

can demonstrate that they operate completely independently from the owner manufacturer 

(design and manufacture of powertrains, receive no fiscal support from owner manufacturer, 

etc.). The LEV Ill program extends SVM status to these manufacturers for criteria emission 

requirements and CARB recommends that this manufacturer category be included in the Tier 3 

program. [EPA-HQ-OAR-2011-0135-4261-A1, attachment pp. 1-2]

Ferrari:

An Operationally-Independent Manufacturer for GHG Purposes Should Have the Same Status 

for Tier 3 Emission Standards. EPA has proposed to allow small volume manufacturers that 

have demonstrated operational independence for purposes of the Agency’s greenhouse gas 

standards to also have the option of complying with the SVM emission standards established 
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under the Tier 3 program (78 Fed. Reg. at 29,917). Ferrari supports this proposal and 

recommends that EPA issue a final rule that considers manufacturers who have met the criteria 

for operational independence under 40 C.F.R. § 86.1838-01(d) for purposes of the GHG program 

as also operationally-independent and similarly eligible for SVM provisions under the Tier 3 

program.

Ferrari supports this approach for several reasons. First, there is no reason why a manufacturer 

that has been found by EPA to be an operationally independent SVM for purposes of the GHG 

program should not be treated the same way under the Tier 3 exhaust emission standards 

program. Further, this option would be consistent with EPA’s past practice of allowing SVMs to 

follow an alternate path to certification using assigned deterioration factors and other, more 

streamlined approaches. It also would ensure that manufacturers are subject to the same 

certification procedures for both the GHG and Tier 3 emission standards. Otherwise, a 

manufacturer could potentially be treated as an SVM for GHG purposes but not for the Tier 3 

program; this could result in unnecessarily duplicative or even conflicting certification test 

procedures.

In addition, the comprehensive examination of a manufacturer’s relationship (or lack thereof) to 

other related manufacturers that is required before a determination of operational independence 

can be made highlights the comparatively low sales volume of SVMs and the need for the more 

flexible SVM compliance options. Also, the extremely detailed application process for a 

determination of operational independence ensures that manufacturers cannot abuse the system 

and the SVM compliance option.

Finally, adopting this option would be consistent with the approach taken by the California Air 

Resources Board (CARB) in its 2012 LEV III final rule. In that rule, at 13 C.C.R. § 1900(22), 

CARB revised the definition of SVM to include operationally-independent manufacturers such 

as Ferrari. CARB’s definition applies both to the GHG program and to emission standards for 

conventional exhaust pollutants. Harmonizing with California would allow manufacturers to 

more efficiently certify vehicles to both EPA and CARB emission standards.

To accomplish this goal, Ferrari recommends that EPA revise the language in 40 C.F.R. § 

86.1838-01(a) to clarify that a manufacturer that has fulfilled the requirements for being 

classified as an operationally-independent SVM shall be treated as an SVM for the purposes of 

all EPA emission standards. Ferrari suggests that EPA revise § 86.1838-01(a) as follows, with 

our recommended revision in underlined text:

§ 86.1838-01 Small volume manufacturer certification procedures.

(a) The small-volume manufacturers certification procedures described in paragraphs (b) 

and (c) of this section are optional. Small-volume manufacturers, including small-volume 

manufacturers that have satisfied the criteria for operational independence under 

paragraph (d) of this section, may use these optional procedures to demonstrate 

compliance with all of the general standards and specific emission requirements 

contained in this subpart.

Finally, these comments are drafted based on the assumption that EPA will treat operationallyindependent SVMs as eligible for the Tier 3 SVM provisions, similar to the way in which EPA 
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has treated such SVMs under the GHG program. If EPA does not issue a final rule adopting this 

approach, then Ferrari will submit additional comments because this would have a vastly 

different impact on our operations and vehicles. 

Our Response:

We requested comment on extending eligibility for the Tier 3 SVM provisions to small 

manufacturers that are owned by large manufacturers but are able to demonstrate that they are 

operationally independent. We established such a provision in the light-duty greenhouse gas 

(GHG) program, and CARB did so in LEV III. Comments from CARB and Ferrari supported 

this extension. No commenters opposed it; however, Advanced Biofuels USA recommended 

caution to avoid advantaging SVMs capable of leveraging parent company resources to 

drastically increase U.S. market share within 2-3 years. Given the establishment of this 

provision in our GHG program, and the value of this extension for harmonization with LEV III, 

we are adopting this change into Tier 3 using the same eligibility criteria as in our GHG 

program, set forth in 40 CFR 86.1838-01(d). We believe these criteria are sufficiently strict and 

objective to address the concerns expressed by Advanced Biofuels USA.

What Commenters Said:

National Propane Gas Association (NPGA):

Among the changes proposed by EPA is the incorporation of CARB’s OBD requirements into 

the federal EPA regulations, thereby requiring compliance with CARB’s provisions. EPA is 

proposing that small business alternative fuel converters have the option to continue to comply 

with EPA’s existing OBD requirements when the Tier 3 standards become effective. EPA goes 

on to state that the OBD requirements would then have to be met by small entities by the 2022 

Model Year. Likewise, as it pertains to exhaust and evaporative emission standards, EPA 

proposes to allow small manufacturers to postpone compliance with the standards and other Tier 

3 requirements until MY 2022, but then require them to meet all the Tier 3 standards for MY 

2022 and later.

NPGA believes that EPA should increase the threshold for small volume manufacturers beyond 

the 15,000 units per year level and that the flexibilities allowed small businesses as noted in the 

NPRM should be allowed to remain in place beyond MY 2022. Small businesses and small 

volume manufactures have limited resources, lower production volume over which to spread 

their compliance costs and limited product lines, which hinder their ability to take advantage of 

the phase-in and averaging, banking and trading provisions. These changes would facilitate the 

increased availability of alternative-fueled vehicles. 

VNG.CO (VNG):

Small-Volume Manufacturer Threshold: Under current Tier 2 rules, compliance flexibilities are 

available to SVMs producing up to 15,000 vehicles per year or OEMs producing up to 15,000 

units of a given small volume test group. The NPRM proposes to decrease this threshold to 5,000 
Chapter 4: Proposed Vehicle Emissions Program

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vehicles for SVMs (but not small volume test groups), based on the rationale that this definition 

was used in the recent 2017-2025 greenhouse gas regulations and that “the 5,000 unit cut-off for 

small volume manufacturers would include all of the vehicle manufacturers, ICIs, and alternative 

fuel converters that currently meet the applicable SBA definition as well as a few additional 

companies that have similar concerns to small businesses.”

While EPA is certainly correct that a 5,000 vehicle cutoff would pose no risk to conversion 

companies currently, the proposed rules will cover the years 2017 and onwards, at which point 

there could be significant growth in the NGV market. Under such a scenario, this changed 

threshold could potentially limit the ability (or willingness) of SVMs to scale up production by 

forcing them to choose between increased sales and increased regulatory burdens at much lower 

production level. Finally, 15,000 vehicles is still just 0.1% of an annual US light-duty vehicle 

market of 15 million vehicles. For all these reasons, EPA should continue to define SVMs as 

producing up to 15,000 vehicles per year. 

Our Response:

We do not believe that the SVM relief provisions are so significant as to cause the selflimiting of sales suggested by VNG, except perhaps for a company very near the threshold.

Even if this were to happen, moving the threshold to 15,000 would not prevent the same dynamic 

from potentially occurring at that sales level. Furthermore, our use of a three-year average of 

sales for determining SVM eligibility protects the SVMs from being disadvantaged for having an 

especially good year not reflective of its long-term sales trend. See the 2017 and later light-duty 

GHG final rule for a discussion of our basis for adopting the 5,000 vehicle threshold (77 FR 

62793, October 15, 2012). NPGA suggested that the small business sales threshold be increased 

to a level over 15,000 but did not provide any detailed reasoning or indicate what that level 

should be. For these reasons, we are not altering the SVM sales threshold from what we 

proposed. The issue of extending small business flexibilities beyond MY 2022 is discussed in 

Chapter 4.6.1.

What Commenters Said:

VNG.CO (VNG):

Level Playing Field Between Small-Volume Manufacturers and Small-Volume Test Groups: 

While existing regulations ostensibly maintain a “level playing field” between converters (small 

volume manufacturers) and OEMs producing limited volumes of a vehicle model (small volume 

test groups), there is an important difference in current administrative requirements for on-board 

diagnostic (OBD) systems testing that disadvantages OEM small-volume production. Moreover, 

the current Tier 3 proposals risks entrenching this inequality for the long term and introducing 

others for both OEMs and converters.

Because of the current lack of CNG refueling services and a more general uncertainty over the 

market appeal of NGVs, automakers have been cautious about producing NGVs in high 
Tier 3 Summary and Analysis of Comments

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volumes. They therefore utilize the same types of low-volume manufacturing processes used by 

alternative fuel conversion companies – and face similar per-vehicle cost challenges.

In its recent, comprehensive Future Transportation Fuels study, the National Petroleum Council 

of the U.S. Department of Energy developed a detailed breakdown of the sources of incremental 

costs for NGVs under both the current low-volume production model as well as under a mediumterm (2020) high-volume original equipment manufacturer (OEM) production scenario. As 

shown below in the examples of a small car and a pickup truck, at low volumes (2010) these 

costs are dominated by fixed costs for design as well as certification and on-board diagnostic 

(OBD) system costs that must be spread over a small volume of vehicles. These incremental 

costs can fall to zero or near-zero with the move to high-volume production (i.e., the 2020 

scenario), under which these fixed costs would be spread across a similar number of vehicles as 

high-volume gasoline-fueled cars and trucks.

Sources of NGV Incremental Costs

Pickup Trucks Small Cars

Cost Component 2010 2020 2010 2020

CNG Fuel Storage (Type I) $2,144 $2,144 $1,590 $1,365 

Compound Mass $945 $899 $655 $623 

Engine Hardening $310 $0 $155 $0 

Certification, OBD, Aftertreatment and Calibration $4,481 $0 $1,535 $0 

Engine & Vehicle Fuel Delivery System & Safety Integration $3,788 $419 $3,670 $345 

Total Incremental Cost $11,668 $3,462 $7,605 $2,333 

Source: National Petroleum Council, Future Transportation Fuels: Natural Gas Analysis pp. 53-58

While OEMs are much larger entities than conversion companies and could potentially produce 

NGVs at much lower incremental costs with high-volume, assembly line production, automakers 

are highly competitive and are unlikely to risk committing resources required to move to highvolume production until natural gas refueling availability improves and the mass-market appeal 

of NGVs is better established. This results in a “vicious cycle,” with automakers and converters 

producing low volumes of high-priced NGVs which limits their market appeal and which in turn 

limits the development of natural gas fueling services infrastructure, which in turn reinforces the 

low-volume/high-cost production model.

This vicious cycle could be changed into a “virtuous cycle” by ensuring a truly level playing 

field for both OEMs and converters that would allow for fully-harmonized, reduced regulatory 

barriers to entry for both at production volumes of up to 15,000 vehicles per SVM or per OEM 

small-volume test group. Encouraging gradually greater quantities of small-volume NGVs to be 

introduced by both converters and OEMs would stimulate accelerated development of CNG 

fueling services infrastructure, which in turn would increase the market appeal of NGVs, which 

would ultimately lead to the production of low-cost NGVs on a high-volume basis that would 

then meet full large-volume certification requirements. This dynamic has already been successful 

in building the market for NGVs in Europe, where several OEMs have developed the market 

through the production of a wider range of models on a small-volume conversion basis.
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40 CFR §86.1838–01 ostensibly provides such a path by allowing OEMs to use small-volume 

manufacturer (SVM) certification procedures – including the use of assigned deterioration 

factors and reduced in-use testing requirements – for test groups of vehicles which total less than 

15,000 units, called small-volume test groups. However, as discussed below, in the area of OBD 

system demonstration, EPA allows for significantly reduced requirements for only SVM 

converters. Moreover, the current NPRM risks entrenching this arbitrary distinction between 

OBD requirements for SVM converters and OEM small-volume test groups while creating other 

inequalities between these two classifications. This runs contrary to the EPA’s own goal of 

maintaining “a level playing field for OEMs and conversion manufacturers,” as expressed in its 

revised aftermarket certification rules in 2011: 

EPA also believes that a certification demonstration requirement for new vehicle and 

engine conversions is prudent to maintain a level playing field for OEMs and conversion 

manufacturers. The certification requirement for new vehicle and engine conversions 

reduces any incentive that might otherwise exist for OEMs to circumvent requirements 

by certifying a traditional configuration and then converting it, rather than certifying the 

alternative fuel configuration in the first place.

This level playing field should work both ways, ensuring that both types of entities can produce 

small volumes of alternative fuel vehicles with reduced and harmonized regulatory obligations. 

Some disharmonies included in the NPRM risk undermining incentives for OEMs to produce 

NGVs in small volumes; others have the potential to risk discouraging conversion companies 

from scaling up their own production. In both cases, it is critical for EPA to avoid placing 

unnecessary regulatory burdens on the production of NGVs at this early stage of the market, or it 

risks making the present “vicious cycle” a permanent feature of the market, with NGV 

production limited to small-volume, high-cost vehicles with limited customer appeal.

A true level playing field can be accomplished by making changes to the proposed Tier 3 rules in 

the following three areas:

1. OBD testing requirements

2. Extended lead time provisions

3. Small-volume production thresholds 

The Tier 3 rules are projected to have enormously positive impacts for local air pollution issues. 

However, if not implemented carefully, they could also inadvertently impede the development of 

vehicles fueled by natural gas – a critical clean fuel for the highly efficient internal combustion 

engines of the future as well as a bridge to zero-emission hydrogen FCEVs. Conversely, if these 

rules are implemented thoughtfully, they could provide an opportunity for EPA to reinforce the 

support for NGVs it showed in the 2017-2025 GHG rulemaking, as well as the support for this 

technology that President Obama has repeatedly asserted.

The proposals outlined in these comments would significantly reduce the regulatory barriers to 

entry for OEMs producing limited quantities of NGVs by more fully harmonizing rules for 

small-volume test groups with the rules for small-volume conversion manufacturers –

particularly in the critical area of OBD system testing requirements. Additionally, by avoiding 

unnecessary sulfur requirements for CNG fuel, EPA will assure gas producers, utilities, and 

retailers that the development of the NGV fueling market can proceed without unexpected 
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regulatory roadblocks. In combination, these efforts can help transform the current “vicious 

cycle” of low-volume, high-cost NGVs and sparse CNG fueling into a “virtuous cycle” of highvolume, low-cost NGVs with plentiful CNG availability. 

Our Response:

The flexibilities we are adopting for small companies are prompted by their limited 

access to engineering resources and credit opportunities, as discussed in Section IV.G of the 

preamble to the final rule. These issues are far less present for larger OEMs, even for their small 

volume test groups. Many new technologies must undergo start-up challenges similar to those 

described by VNG for NGVs, and manufacturers will often discount the retail price of vehicles 

using these technologies so as to help overcome these challenges, or will partner with others to 

spread development and implementation costs. Given that manufacturers have significant 

latitude in defining test groups, extension of small business flexibilities to large manufacturers’

small volume test groups could provide large unintended incentives to artificially create small 

volume test groups and seriously hamper the Tier 3 program, and could introduce new 

competitive issues, including for the small companies these provisions are designed to help. We 

believe that the small manufacturer flexibilities should remain firmly focused on the specific 

issues that arise for small businesses under the Tier 3 program. We note that larger OEMs 

themselves did not argue for extension of these flexibilities to their small volume test groups.

4.6.6. Credits

What Commenters Said:

Ozone Transport Commission (OTC):

EPA’s proposal would prevent the carryover of Tier 2 credits for use in meeting the Tier 3 

standards. However, while large volume manufacturers may be well-positioned to achieve 

compliance with the Tier 3 standards using only the credit flexibility mechanisms included in the 

proposed rule, small volume manufacturers may have more difficulty achieving the reductions 

necessary for early credit generation. These manufacturers have limited model lines with which 

to comply with fleet average requirements, and lesser availability of investment and engineering 

resources to meet more stringent standards. Therefore, they may be disadvantaged under the 

current credit structure. Therefore, OTC recommends that EPA allow carryover of Tier 2 credits 

for small volume manufacturers with a mechanism similar to California’s carryover provisions 

between the LEV II and LEV III programs, under which credits are initially available at full 

value, but then discounted over time. OTC believes that this option best accounts for the 

challenges small volume manufacturers may face in complying with the program, and levels the 

playing field for firms that may be unable to utilize the currently proposed flexibility 

mechanisms. 

Our Response:
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Under our Tier 2 program, credits may be earned for NOx but not for NMOG+NOx, so 

allowing manufacturers to port excess Tier 2 credits into Tier 3 to demonstrate compliance with 

NMOG+NOx standards would introduce significant complexities. Instead we decided to allow 

the generation of Tier 3 NMOG+NOx credits early, and this flexibility is available to large and 

small manufacturers alike. However, as pointed out by a number of manufacturers, the ability of 

SVMs to take advantage of averaging, banking, and trading flexibilities of any sort is limited by 

their limited product offerings, and for this reason we are adopting special flexibilities for SVMs 

that do not depend on credits. Additional discussion of comments requesting conversion of preTier 3 credits to Tier 3 NMOG+NOx credits can be found in Chapter 4.2.5.

Ferrari:

Ferrari suggests a debit/credit trading mechanism in order to be able to guarantee compliance 

with the emissions standards proposed by EPA for 2022 and subsequent MYs. A debit/credit 

trading scheme would enable Ferrari to internally generate credits through over-compliance, or 

obtain credits from other manufacturers for their over-compliance with the fleet average 

emission standards. This approach would not result in any harm to the environment as the same 

overall net emissions level would be maintained. In fact, due to the very low mileage that is 

typical of most Ferrari vehicles, a credit trading program could result in a net environmental 

benefit because the credits would cover full useful life emissions while the mileage of most 

Ferraris does not even approach 150,000 miles. 

Ferrari proposes that EPA allow NMOG+NOx credits earned by small volume manufacturers to 

expire after ten years instead of five. As explained in our November meeting with you, meeting 

the 30mg/mile standard in 2028 would require the introduction of vehicles with much lower 

emissions as early as 2022, which may be extraordinarily difficult to do. The extended credit 

lifespan would provide Ferrari with the lead time to ensure compliance with the proposed 

standards without sacrificing the performance or character that is expected of each Ferrari 

vehicle. Ferrari agrees that any credits earned during an extended compliance period may not be 

sold, traded, or otherwise transferred to another manufacturer. 

Our Response:

As discussed in Section IV.A.7.m of the preamble to the final rule, in response to 

comments we received on the proposal, we are extending the life of NMOG+NOx credits earned 

in MY 2017-2024 (MY 2018-2024 for larger light-duty vehicles), to as long as 8 years, 

compared to the 5 years we proposed. For SVMs choosing to take advantage of the 3-stage 

compliance option, these credits could be earned beginning in MY 2022 when the second-stage 

standard takes effect. We believe that this credit life extension substantially addresses Ferrari’s 

concerns. The low-emissions vehicles they would introduce in MY2022 (as well as those sold in 

MY2023-2025) can earn credits that may be used anytime through MY2030. This provides 3 

model years, MY2028-MY2030, in which these banked MY 2022-2025 credits can be used to 

demonstrate compliance with the 30 mg/mi standard under the SVM 3-stage compliance option.
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4.7 Compliance Provisions

4.7.1. Exhaust Emission Test Procedures

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

NMOG+NOx contribution factor for Plug-In Hybrid Electric Vehicles (PHEVs): PHEVs only 

use electricity for a portion of their driving time and generate no exhaust pollution (NMOG, 

NOx, PM, etc.) during this portion. Thus, these vehicles produce less real-world pollution than a 

vehicle certified to the same standard that does not have the off-vehicle charge capability. For 

example, a PHEV that operates half the time on electricity only, will emit half the criteria 

exhaust emissions. Although the benefit is clearly operator dependent, it could be roughly 

approximated by the battery-only range of the vehicle (i.e., a longer battery-only range will result 

in more battery-only miles). 

Recognizing this characteristic of PHEVs, the LEV III regulations include the NMOG+NOx 

Correction Factor for Off-Vehicle Charge Capable Vehicles in §1961.2(b)(1)(B)1.c.2. Under 

LEV III, the NMOG+NOx emissions used to calculate the fleet average emissions are reduced 

by up to the next lowest category based on the battery-only range (i.e., longer range = greater 

reduction). For example, this could allow a PHEV certified to Bin 125 to be treated in the fleet 

average as a Bin 70. Regardless of range, the lowest value that a Bin 125 could use in the fleet 

average is 70 mg/mile; it could not, for example, be treated as a Bin 50. Thus, the correction 

factor in ARB’s LEV III regulations is conservative but is an appropriate recognition of the 

technology’s benefits. EPA did not include a similar correction factor at all in its proposed 

regulations and should adopt this allowance in the final rule. 

Manufacturers and ARB are gathering data on PHEV usage. This data is expected to influence 

the NMOG+NOx contribution factor. For example, it’s possible that a Bin 70 PHEV with a long 

range should use 35 or 25 mg/mile for the fleet average calculations. 

Manufacturers will introduce significant volumes of PHEVs in the coming years. A change to 

incorporate the NMOG+NOx contribution factor for PHEVs is essential to harmonize the 

programs and prevent manufacturers from being forced to manage separate federal and 

California fleets. 

Recommendation: We recommend that EPA harmonize with the LEV III allowance for PHEVs. 

Once more data is available, we would also like to work with both agencies to determine if the 

cap at the next lowest category is appropriate or should be eliminated. 

BMW of North America, LLC

Plug-in hybrid vehicles offer a promising technology on the path towards ambitious GHG targets 

and further reduction of oil dependency in the transport sector. 
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Depending on the trip length and zero emission driving capability of the vehicle, a portion of 

vehicle miles travelled (VMT) with PHEVs is based on mere use of electricity hence reducing 

the overall exhaust emissions of the PHEV substantially. CARB acknowledges and rewards the 

electric drive share of PHEVs through allowing for an HEV contribution factor which based on 

Zero-Emission VMT reduces the NMOG+NOx value for PHEVs. 

BMW proposes harmonizing Tier 3 with LEV III through adoption of the PHEV allowance in 

Tier 3 final regulation for all 50-state certified PHEVs. 

Our Response: 

The CARB ZEV mandate requires manufacturers to produce and sell zero emission 

vehicles. The LEV III program provides manufacturers with emission adjustments for advanced 

vehicles like PHEVs. The adjustments are based on expected emissions reductions from the 

electric operation portion of driving in the California market. Similar information was not 

provided to EPA and since Tier 3 does not have a ZEV requirement, we did not propose and are 

not adopting PHEV adjustment factors.

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global):

PHEVs were introduced just a few years ago, and both the agencies (EPA and ARB) and 

automakers are still developing the vehicles and the test procedures for those vehicles. In 2009, 

before any PHEVs had been introduced, ARB adopted PHEV test procedures for California. In 

June, 2010, the Society of Automotive Engineers (SAE) J1711 Committee (which includes EPA, 

ARB, automakers, and automotive suppliers) approved a recommended practices document that 

contains detailed test procedures for PHEVs. The test procedures contained in SAE J1711 

represent the latest and best collaborative effort to test these new vehicles. Most recently, EPA 

adopted PHEV test procedures in July, 2011. The EPA requirements reference many of the test 

procedures contained in SAE J1711. 

Since EPA adopted PHEV test procedures in 2011, manufacturers and the agencies have gained 

significant experience developing, validating, testing, and certifying these vehicles, with a 

growing number of PHEVs are on the road from more manufacturers with more attribute sets. As 

this occurred, industry worked to develop a set of recommended changes to the PHEV test 

procedures that we believe maintain the stringency of the standards and the benefits of these 

vehicles, while streamlining the testing. 

We have met with EPA and ARB staff several times over the last few months and sincerely 

appreciate the efforts of both agencies to consider and discuss our recommendations. Appendix 2 

[See the attachment in Docket number EPA-HQ-OAR-2011-0135-4461-A3] contains a 

comprehensive list of the changes we have recommended to the EPA (and ARB) test procedures. 

We highlight two important issues below, although these are also addressed in Appendix 2. 
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CS Worst Case, Manufacturers Attest That CD Emissions Will Be Lower when the Utility Factor 

(UF) is Used: PHEVs have two primary operating modes – charge depleting (CD) and charge 

sustaining (CS). In CD mode, the battery provides all, or at least some, depending on the 

PHEV’s design, of the power to drive the vehicle. In CS mode, the gasoline engine provides all 

of the power to drive the vehicle either through a direct connection to the drive train, or by acting 

as a generator to deliver electricity to the electric motor. 

Manufacturers must certify that PHEVs will meet the emission standards in CS mode, which is 

real-world worst-case since it represents a driver who never charges the vehicle and thus never 

uses the battery for propulsion. To the extent that a vehicle uses the battery for propulsion, the 

emissions during that period would be zero and thus would lower the overall emissions from the 

vehicle. In addition to CS mode, manufacturers must also certify that their vehicles will meet the 

emissions standards in the “worst-case” CD mode. 

The method used to test “worst-case” CD mode is to drive the vehicle from a full charge over 

consecutive Urban Dynamometer Driving Schedules (UDDS)13 until the engine starts and then 

run one additional UDDS. Emissions are measured during the UDDS when the engine starts and 

over the next UDDS. This can lead to a situation where a vehicle has two cold starts (one at the 

very end of the first UDDS and another during the second UDDS) and appears to not meet the 

emission standard regardless of the zero emission miles traveled prior to the first cold-start. This 

does not represent any real-world condition. In fact, PHEVs will have far lower emissions than 

non-PHEVs certified to the exact same standard. 

For example, GM provides data for the Chevrolet Volt on the total number of miles driven 

compared to the total number of all-electric miles (see http://www.chevrolet.com/volt-electriccar.html). As of May 27, 2013, Volts have driven a total of 310 million miles, of which 192 

million miles were all-electric. Thus, more than 60 percent of the miles driven on the Volt 

produce zero emissions. If the Volt is certified to a Bin 30, this would translate into real world 

emissions of about 12 mg/mile (= 30 * 0.4). We recognize that this will vary depending on the 

vehicle design, all electric range, etc. However, it is indisputable that a PHEV will emit less than 

a conventional vehicle certified to the exact same emission standards. Yet manufacturers spend 

two to three times as much effort to certify a PHEV compared to a conventional vehicle. This is 

especially significant given that PHEV test groups are relatively low volume compared to 

conventional vehicle test groups and manufacturers face greater challenges in trying to make 

PHEVs profitable. 

The driving cycles used for decades – Federal Test Procedure (FTP), UDDS, US06, etc. – were 

developed by monitoring driving behavior and choosing what would be an average driving cycle. 

No one drives a vehicle exactly according to an FTP cycle. However, on average, the FTP cycle 

is a good approximation. Likewise, the SAE J1711 and Part 600 procedures include a UF that 

approximates the amount of driving on the battery and the amount of driving with the engine. 

Again, perhaps no single vehicle mirrors the exact UF split in electric versus gasoline propulsion, 

but on average the UF is a good approximation of the average. In fact, EPA uses the UF for 

GHG emissions, but does not allow its use for criteria emissions. 
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Because the UF effectively mirrors total real-world emissions (SAE J2841) from a PHEV, EPA 

has expressed concern that manufacturers could use this to increase the air-to-fuel ratio, improve 

fuel economy and reduce GHG emissions at the expense of increased NOx emissions when 

compared to a CS test. This is a legitimate concern that EPA could address with the current 

defeat device regulations. If EPA needs further assurance, it could specify that the vehicle 

emissions system must perform in a similar manner at the same auxiliary power unit (APU) 

speed and load point on both the CS and the CD mode. 

Recommendation: The following three requirements should address EPA’s concerns with the 

criteria emissions. These assure that a vehicle that is never charged meets the emission standards, 

and that vehicle emission controls operate in a similar manner whether in CD or CS operations: 

1. Vehicle must meet the emission standards in CS operating mode. 

2. Vehicle must meet the emission standards in CD operating mode when the UF is applied. The 

manufacturer may attest to meeting this requirement. 

3. The vehicle emission system must operate in a similar manner when operating at the same 

APU speed and load point in either CS or CD mode. 

Net Energy Change (NEC) Tolerance and Use of Appendix C: CS tests are intended to determine 

emissions when the gasoline engine is providing all of the propulsion power. However, PHEV 

systems are complex, and the gasoline engine is designed to operate at maximum efficiency. This 

means that all of the power of the gasoline engine may go to providing propulsion at some times, 

while at other times it may be used to charge the propulsion battery; at other times, the 

propulsion battery may discharge further to provide peak or transient power. Consequently, 

while the vehicle is operating in CS mode, the battery state of charge may slightly change. To 

verify that the gasoline engine is providing all of the power over the CS test, SAE J1711, ARB, 

and EPA procedures require that the vehicle operate within a NEC tolerance of 1 percent of the 

total fuel energy. 

As propulsion batteries become larger and the control systems more sophisticated, maintaining 

NEC within 1 percent becomes more difficult. The SAE J1711 committee recognized this 

difficulty and developed a method to correct an NEC of greater than 1 percent but less than 5 

percent back to an equivalent of NEC = 0. This NEC correction of up to 5 percent is contained in 

Appendix C of SAE J1711. 

The CS test is difficult, time consuming, and resource intensive, and if the vehicle misses the 

NEC tolerance, a complete retest over that cycle is required. Allowing use of Appendix C to 

correct NECs of less than 5 percent would significantly reduce the amount of retests conducted. 

Moreover, it would allow manufacturers to develop vehicles with better performance. 

We understand that both EPA and ARB are concerned that if a vehicle is certified over the CS 

test with a -5 percent NEC, then emissions would be under-reported, since 5 percent of the 

vehicle’s propulsion came from the zero emission battery. However, SAE J1711, Appendix C, 

corrects the measured fuel consumption back to NEC=0. Moreover, manufacturers would be 

required to meet the emission standards provided at any NEC between ± 5 percent. Thus, the 

vehicle must meet the emission standard if the NEC is +5 percent as well. 
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We agree that manufacturers should declare the use of Appendix C at an early point in the 

certification process. Automakers would agree to provide this information in the pre-certification 

meetings. 

Recommendation: We recommend that EPA allow the use of SAE J1711, Appendix C, 

correction for NEC tolerance greater than one percent, provided the manufacturer declares its 

intention to use this during the pre-certification meeting. Moreover, manufacturers support a 

requirement that the vehicle must meet the emission standards within the full range of the NEC 

±5 percent (with fuel consumption corrected per SAE J1711, Appendix C). 

Our Response:

With regard to the recommendations on how PHEV’s should be assessed in charge 

depleting and charge sustaining modes; we have addressed these recommendations in a memo to 

the docket which summarizes our test procedure changes. In summary, we have not adopted 

these recommendations as part of Tier 3 as we did not have adequate information on which to 

base our decision. We will continue to work with manufacturers to address concerns with 

current PHEV test procedures.

With respect to the NEC tolerance, EPA has adopted the recommendation made by the 

Alliance and Global Automakers, however, manufacturers wanting to exercise the option of 

using NEC +/-5% will be required to apply for permission to use this procedure and receive prior 

approval from EPA.

What Commenters Said:

Organization: BMW of North America, LLC

In-Use Testing of PHEV`s:

The in-use requirements for Carbon Related Exhaust Emissions (CREE) of PHEV`s were 

changed in 2012. Prior to this modification, the CREE was calculated separately for depleting 

and sustaining operation modes. The new language requires combining depleting and sustaining 

modes by the utility factor. However, the utility factor is determined by the depleting range; 

hence the new language makes the depleting range the key influence on in-use performance. 

Over useful life the depleting range is reduced as a result of aging of the traction battery. 

To date very little experience exists on battery deterioration in actual customer use. 

BMW finds the new in-use requirement premature and recommends that the feasibility of this 

approach be evaluated on the variety of PHEV concepts manufacturers are introducing into the 

market to better assess the effects of long-term customer use. Further, BMW recommends reintroducing the PHEV in-use requirements from May 2010 wherein depleting and sustaining 

operations are treated separately in CREE calculations. 
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Once long-term behavior is better understood through sufficient field data and impact analysis, a 

combined CREE calculation (depleting and sustaining modes) based on the depleting range 

could be re-introduced, provided available battery technologies support the approach. 

Our Response:

BMW commented that in the 2012 light-duty Greenhouse Gas (GHG) regulations the inuse requirements for measuring and calculating Carbon Related Exhaust Emissions (CREE) for 

plug-in hybrid vehicles (PHEV) was calculated separately for charge depleting and charge 

sustaining operation modes, but that in the 2017 GHG rule, EPA changed the requirements so 

that in-use CREE is calculated by combining the depleting and sustaining modes using a utility 

factor. Their concern is that the utility factor is determined by the depleting mode driving range 

thus making the depleting range the key influence on in-use performance. They argued that there 

is very little experience with battery deterioration in actual use and that it is premature to use this 

approach. They suggested that more information on battery deterioration was necessary and that 

in the future it may be more appropriate to determine in-use performance for PHEVs by using a 

utility factor and combining depleting and sustaining modes. 

BMW’s comments are related to the GHG regulations and are not directly related to the 

Tier 3 rule. While their comments do discuss in-use emissions and how they would be calculated 

for IUVP, they are not related to anything that was proposed or discussed for the Tier 3 rule. 

However, EPA will address some of their concerns. BMW is fundamentally wrong when they 

state that EPA originally specified separate in-use CREE standards for charge-depleting and 

charge-sustaining modes. The 2012-2016 GHG final rule specified, for dual fuel vehicles 

(including PHEVs), that there should be an in-use standard for each fuel, not for each mode. (See 

75 FR 25687, May 7, 2010.) PHEVs were included with other dual fuel vehicles, where the 

CREE (or CAFE) value is based on test results on each fuel (e.g., gasoline and E85). Obviously, 

each in-use test for most such vehicles should be done on one fuel or the other, especially for 

dual fuel vehicles where the fuels can be mixed in the same tank (e.g., gas-E85 FFVs). Such an 

approach might have worked for the Volt (a series PHEV), which at the time was the only PHEV 

with which EPA had any experience. However, by the time of the 2017-2025 GHG rule (see 77 

FR 63158, October 15, 2012), we realized that PHEVs did not generally fit the mold of other 

dual fuel vehicles. With blended PHEVs, for example, it is simply impossible to test either on 

gasoline or on electricity, or to specify standards separately for each fuel. It was in the 2017 

GHG rule that we changed the language for PHEVs, requiring that PHEVs be tested as they are 

for certification, using a utility factor weighted composite of charge-depleting and chargesustaining operation.

Contrary to BMW’s assertions, we never considered separate charge-depleting and 

charge-sustaining standards. PHEVs are a unique technology. While the in-use performance of 

FFVs can be typically assessed by testing on either or both fuels, this is not the case for PHEVs, 

where the two fuels can be inextricably intertwined, and where the battery performance over

time can have an impact on in-use GHG emissions. The GHG emission standards are full useful 

life standards, and the regulations require manufacturers to account for battery deterioration in 

their certification values (which are likewise required to represent full useful life values). While 

we agree with BMW that battery performance over time can affect in-use GHG emissions, it is 
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precisely for this reason that in-use testing must assess the composite of charge-depleting and 

charge-sustaining operation. If manufacturers appropriately account for battery deterioration in 

their certification values, then they should have no concerns. BMW is in effect asking that the 

fundamental basis of in-use testing – to produce a fair comparison between certification and inuse emission levels – be set aside for PHEVs. In a fleet-averaging program in particular, EPA 

believes it is important to assess in-use performance against certification levels.

What Commenters Said:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

EPA proposes to confirmatory test vehicles on four wheel (4WD) dynos as soon as 90 days after 

the Final Rule, even if they were originally certified by the manufacturer on a two-wheel (2WD) 

dynos. Such a change in dyno requirements would be a change to the yardstick used to determine 

fuel economy, and would significantly impact the measurement of fuel economy. While EPA 

would be obligated to release a Test Procedure Adjustment (TPA) for CAFE, EPA would need to 

also change GHG rule targets and label procedures. Since the yardstick at the EPA lab would be 

changed, manufacturers would be effectively forced to install 4WD dynos at their facilities to 

ensure correlation with the new EPA yardstick, with a massive capital cost for new equipment 

and new facilities. But studies and test data have not yet laid to rest basic questions concerning 

the higher variation in results on 4WD dynos or their effects on fuel economy or even their 

representativeness of on road behavior. 4WD dynos, as they are proposed to be used in the 

NPRM, may turn out to not be a better representation of on-road behavior, but just another, 

different representation, with new and different measurement offsets and correlation issues. 

Given that basic questions have yet to be answered, and that these questions were not addressed 

at all in the NPRM or in the RIA, we disagree with EPA adopting 4WD confirmatory testing, as 

this change in test procedure would require appropriate application of the dyno factor and CAFÉ 

TPA, GHG standards adjustments, and would be coupled to significant lead time, dramatic cost 

impacts, loss of emissions testing capacity and increased variability. 

EPA’s Proposal for 4WD Dyno Confirmatory Tests is Premature and Should not be Adopted: 

Not discussed in the preamble part of the Tier 3 NPRM, but included only in the draft regulations 

section (78 Fed. Reg. 30163, § 1066.410 (g), Dynamometer Test Procedure) is a significant 

change to current test procedures. EPA proposes to confirmatory test vehicles on 4WD dynos 

even if they were originally certified by the manufacturer on a 2WD dyno. Such a change would 

impact the measured fuel economy of a vehicle and effectively forces manufacturers to install 

4WD dynos in order to minimize the risk of not correlating with the results of the EPA lab. This 

EPA lab test procedure change measurably impacts fuel economy and thus is a change to test 

procedures which requires a TPA. [EPA-HQ-OAR-2011-0135-4461-A1, p. 100]

First, the Alliance and Global Automakers recommend that EPA not adopt the proposed change 

and that EPA instead continue to follow established policy of confirmatory testing vehicles as 

OEMs do on the same dyno type as used by the manufacturer. EPA should continue the current 
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policy of only using 4WD dynos for non-confirmatory testing and for data collection purposes 

for the following reasons: 

It is premature to require confirmatory testing on 4WD dynos because there has been insufficient 

analysis and research performed on 4WD dynos to fully understand their operation and minimize 

test result variability to acceptable levels. For the switch from the Clayton twin-roll dyno to the 

48” single-roll electric dyno in the 1990’s, both EPA and industry cooperated in a large study to 

determine the necessary changes to calibration and setup procedures to ensure good correlation 

between EPA and industry’s dynos (92). Based on a preliminary EPA and Alliance/Global 

Automakers study, attached as Appendix 9, 4WD dyno correlation is not predictable or well 

understood for even simple, “passive” 2WD vehicles. For this reason, meaningful conclusions 

cannot be drawn from 4WD dyno test results at this time. This may be due to the great variations 

in designs (four motors, motor in the middle, location of load cells, location of speed acquisition, 

parasitic loss adjustments, roll speed synchronization, flexible versus rigid vehicle tie downs, 

etc.), or it may be due to setup and testing procedures not being defined and standardized. The 

Alliance and Global Automakers strongly recommend that much more testing and analysis must 

be performed before 4WD dynos can be adopted for confirmatory testing. 

By instituting a test procedure change to confirmatory test vehicles on a 4WD dyno even if the 

manufacturer certified on a 2WD dyno, EPA is effectively requiring manufacturers to install 

4WD dynos in order to minimize the risk of not correlating with the EPA lab. This would impose 

an extraordinary burden on industry in terms of cost and practicality for manufacturers to install 

4WD dynos for fuel economy and certification testing. Since the requirement could be 

implemented by EPA 90 days after publication of the Tier 3 Final Rule, over a very short time, a 

large number of 4WD dynos would need to be purchased and installed because of the great 

volume and frequency of certification and fuel economy tests performed by manufacturers. In 

many instances this would not be practicable, since many facilities in current use cannot be 

modified to accept the increased space requirements for 4WD dyno testing with their 

requirements for large underground pits. New buildings and test cells would be required in many 

cases to accommodate a 4WD dyno at a test facility. 4WD dynos would be required to be 

installed in environmental chambers to be able to perform 20°F, SC03 and AC17 tests. Many 

existing environmental chamber test cells will not be able to accommodate the installation of a 

larger pit and extra roll for a 4WD dyno. Finally, the cost for each 4WD dyno is more than 

double the cost of two 2WD dynos, due to the necessary and more complex hardware/software to 

synchronize two rolls and to move one roll to accommodate varying wheelbase vehicles. 

4WD dynos have a particular burden associated with them in terms of the greater floor area 

required for their installation. The footprint area requirement for a 4WD dyno is partly a result of 

the two rolls, with one of the rolls being a movable roll, but is more a result of the unique vehicle 

tie-down arrangements necessary on a 4WD dyno. Differently than on a 2WD dyno, a vehicle is 

required to be restrained in all directions to maintain its contact at the top of the two rolls. Such a 

vehicle restraint system, be it a rigid type or a flexible type, requires sufficient space around all 

the sides of the vehicles to be able to resist the substantial forces during a test. On average, 4WD 

dyno test cells require approximately 3 to 4 times more square feet of floor space than do 2WD 

dynos. Appendix 10 provides examples of predicted floor space requirements for manufacturers 

to implement the 4WD dyno confirmatory proposal. As can be seen graphically in the first 
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example, the floor space that is currently able to accommodate five 2WD dynos would only be 

able to accommodate three 4WD dynos. A new facility would be required to be built to 

accommodate the other two 4WD dynos which are needed to maintain the same test production 

capacity. 

For some manufacturers, expansion of an existing facility may be possible, and for some 

manufacturers entirely new facilities would be required. However, some manufacturers are so 

real estate constricted that to add 4WD dynos at an existing location would require them to build 

vertically rather than horizontally, and the cost of expansion for those manufacturers would be 

significantly higher. 

In order to better quantify the potential burdens associated with this proposal, manufacturers 

developed an overall industry cost estimate based on a survey of cost estimates from individual 

manufacturers for the purchase and installation of 4WD dynos. The cost estimate includes 

estimated costs for 4WD dynos (including individual selections of 4WD dyno technologies, such 

as location and number of power absorbers, and power ratings) and estimated costs to prepare the 

test sites to accept the 4WD dyno. These costs include digging larger pits in existing test cells, 

reconfiguration of existing equipment to accommodate 4WD dynos, and, where necessary, 

construction of entirely new facilities to maintain production capacity during and after 

construction. Based on this industry cost estimate, attached as Appendix 11, the one-time cost 

burden to implement the EPA proposal would be in a range from $1.031 billion to $1.246 billion. 

The cost estimate is conservative and an actual cost would likely be much greater, since the 

number of dynos to be replaced is not actually proportional to vehicle sales.. The ongoing cost 

burden to operate and maintain 4WD dynos with their reduced throughput and higher 

maintenance needs would be significantly increased as well, but is not quantified in the cost 

estimate. 

These high costs make it very clear that before a switch to 4WD dynos can be contemplated, a 

rigorous analysis of costs and benefits needs to be performed, including evaluations of 

potentially less costly alternatives. Since such an analysis was not included or even addressed by 

the NPRM or the RIA, it is unclear how procedurally such a costly requirement could even be 

proposed. 

The Alliance and Global Automakers also have concerns with a reduced test throughput from a 

4WD dyno confirmatory requirement. The vehicle setup burden would be increased, not reduced. 

Previously, EPA has not released any guidance on standardizing methods for vehicle tie down on 

4WD dynos. There are increased concerns with safety because of the more complex vehicle tie 

down arrangements required. Wheel chocks cannot be used on 4WD dynos and most vehicles are 

not equipped with trailer hitches and front tow hooks, requiring ad-hoc welding/securing of tiedown fixtures to vehicle frame - often impractical for customer vehicles and inherently unsafe. 

Specific and detailed procedures are necessary for how to tie down a vehicle, align the vehicle to 

the dyno rolls to minimize skewing, and how to account for any potential interaction between the 

4WD dyno and 4WD/AWD vehicle torque distribution control systems, which in some cases 

may result in on-dyno AWD system activation that is not representative of its “on-road” 

behavior. Such guidance is needed before EPA and Industry can successfully implement a 4WD 

dyno confirmatory testing requirement. 
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Organization: Ford Motor Company (Ford)

Four-Wheel Drive (4WD) Dynamometer Testing: In the NPRM, EPA proposes to change its 

policy regarding 4WD dynamometer testing. There are two components of the proposal:

(1) EPA proposes to perform confirmation testing of four-wheel drive vehicles using four-wheel 

drive dynamometers, even if a manufacturer tests such vehicles using a two-wheel drive 

dynamometer.

(2) EPA has also proposed that starting in 22MY, manufacturers may continue to test four-wheel 

drive vehicles using 2WD dynos, but only if there is no decrease in emissions or energy 

consumption relative to on-road operation. 

Our concerns with these proposals are provided below:

Added Complexity – The core argument in support of 4WD dynamometer testing is that it 

should, in theory, better represent a vehicle’s “on-road” performance. This is true in the sense 

that all four wheels are rotated when testing on a 4WD dyno, however, the benefits of including 

this additional vehicle component must be weighed against the added complexity that is 

necessary to accomplish this seemingly simple task. 

This added complexity includes:

(1) a second 48” dynamometer roll electrically coupled to the primary roll that requires the 

dynamometer control system to continually distribute and rebalance the target road load between 

the two axles in response to both changing roll speed and changing vehicle torque distribution, 

while at the same time maintaining a high degree of speed synchronicity between the rolls;

(2) fundamentally more complex and error prone vehicle positioning and securing process due to 

the inability to secure the tires of a “non-drive” axle;

(3) varied and complex restraint systems (chains, cables, and rigid fixtures);

(4) non-existent or inconsistent attachment points for these restraints on the vehicle and/or 

vehicle frame;

(5) four tires rotating on rounded surfaces (vs. a “flat” road) resulting in less contact area and 

higher rolling resistance, which requires the dyno to “assist” the vehicle at low speeds;

(6) dyno simulation of “negative” inertia for vehicles with test weights that are less than the 

combined base inertia of two dyno rolls; This complexity adds variability, and also likely 

contributes to correlation differences between 4WD and 2WD testing that should not be 

attributed to a vehicle tested in 4WD dyno mode. With sufficient study the inherently greater 

complexity of 4WD dyno testing can be better managed than it is today, but it is not certain that 

4WD testing will be able to achieve the same level of consistency as the existing 2WD 

procedures. 

Test Procedure Capability – Manufacturers have had very little experience using 4WD 

dynamometers, and as a result, best practices needed to ensure repeatable 4WD testing results 

that correlate with existing 2WD procedures are non-existent or not well defined. These practices 

cannot simply be carried over from the 2WD testing paradigm since they must address issues 

unique to 4WD dyno testing (see sources of added complexity above). EPA and Industry have 

been working to develop such procedures, but this work is incomplete and should be continued. 
Tier 3 Summary and Analysis of Comments

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Correlation to Current 2WD Procedure – EPA has expressed an interest in understanding 

whether the existing 2WD dyno method satisfactorily accounts for vehicle systems that must be 

“disabled” or modified in order to permit operation on a 2WD dynamometer (for example, AWD 

systems). Although 4WD dyno testing may provide a means to answer this question once reliable 

test procedures are in place, the effect of “enabling” such a system can only be isolated if 4WD 

dyno testing in general produces results equivalent to a 2WD dyno for vehicles that do not 

possess such systems. Otherwise, any general testing bias between the dyno modes could be 

falsely attributed to the vehicle system being studied. 

Additionally, since the parasitic drag of a test vehicle’s “second” axle is already included in the 

existing 2WD testing process via the on-road coastdown test, future 4WD dyno testing studies 

should be focused on vehicle technologies that provide some “active“ attribute on this axle that 

cannot be characterized by coastdown parasitics. 

To better understand these issues, EPA and Industry have been conducting a joint, 2WD-to-4WD 

correlation program. Ford commends EPA staff for its continued interest and participation in this 

program, which we believe will ultimately lead to more capable and robust 4WD dynamometer 

test procedures. 

Cost/Facility Impact – 4WD dyno testing is a complex and expensive testing option. Beyond the 

substantial cost of the dynamometer equipment itself, the installation process requires extensive 

site construction and often building modifications, and the additional time needed to align and 

secure test vehicles also reduces the number of tests that can be performed per shift. These costs 

and facility impacts must be carefully weighed against any demonstrated enhancement of 

measurement capability associated with 4WD dyno testing. 

Lead Time – Whenever any new test method is introduced that has the potential to influence test 

results, manufacturers need adequate lead time to prepare for, and transition to, the new method. 

This time is needed to study the impact, develop test procedures, and if necessary, install new 

equipment. It also prevents disruption of programs currently in development using the existing 

procedures. 

Recommendation:

(1) EPA should continue its current policy of conducting confirmation testing in the same 

dynamometer test mode used by the manufacturer. Meanwhile, EPA should continue to work 

with Ford and Industry to:

• Develop and refine best practices for 4WD dynamometer test methods to ensure meaningful 

and repeatable results.

• Complete the ongoing effort between EPA and Industry to establish a robust correlation factor 

between 2WD and 4WD dyno mode to ensure that any future 4WD dyno test results are 

appropriately adjusted to account for overall (i.e., non-vehicle specific) differences between the 

two dyno test methods.

• Once best practices and repeatable correlation factor are in place, conduct testing to 

demonstrate which specific vehicle technologies, if any, would be significantly better 

represented by using 4WD dyno test methods.
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• For the technologies that have been clearly demonstrated to benefit from 4WD dyno testing, 

explore more cost effective options for including this effect in the fuel economy label that would 

not require manufacturers to install and test on 4WD dynamometers. 

(2) Additionally, EPA should continue to define the 2WD dynamometer as the default test mode 

for all vehicles, and refrain from adding any language that would require manufacturers to test 

4WD vehicles on 4WD dynos.

In light of (1) and (2) above, we recommend that the language of proposed § 1066.410 (g) be 

either deleted in its entirety, or revised as follows:

(g) For vehicles which provide four-wheel drive or all-wheel drive operation, manufacturers may 

either utilize the vehicle’s normal (default) mode of operation or test the vehicle on a single roll 

by deactivating the second set of drive wheels. Any confirmatory testing will be conducted in the 

testing mode used by the manufacturer. 

(3) If EPA proceeds with using 4WD dynamometers for confirmation testing in the future:

• EPA should provide manufacturers with adequate lead time to prepare.

• All fuel economy and CO2 results (certification, FE label, CAFE, GHG) generated using a 

4WD dynamometer should be adjusted using the dyno correlation factor currently under 

development by EPA and Industry.

• EPA should apply appropriate test procedure adjustments for CAFE and GHG/CO2 purposes to 

account for any impact the 4WD dyno test methods have on the stringency of these standards. 

Organization: General Motors LLC (GM)

The proposed Tier 3 regulations would effectively require testing of multiple drive axle vehicles 

on 4WD dynamometers (dynos) (ref. Section 1066.410(g)). Additionally the agency has stated

that it reserves the right to include other vehicle configurations like hybrid vehicles in this 

‘4WD’ population, and may, or will confirm manufacturers emissions and fuel economy data on 

4WD dynos, even if the manufacturer did its testing on a 2WD dyno. This is different than past 

practices by the agency which were adopted to minimize sources of variability between 

manufacturers’ testing and the agency’s testing. For OEMs to eliminate any risk at confirmatory 

testing, 4WD dynos will have to be used for a significant percentage of the fleet. 

4WD Dynamometer Test Procedure Adjustment: GM supports the Alliance/Global comments 

with respect to adverse fuel economy impacts associated with 4WD testing, which would require 

EPA to issue a test procedure adjustment (TPA). However, data indicate that test to test 

variability along with cycle to cycle variability may prohibit the establishment of a robust TPA 

value at this time. The source of this variability is not understood, and likely is a function of 

several equipment and setup parameters. 4WD dyno testing is more complex than 2WD testing, 

and to state it simply, more things can go wrong. This needs to be thoroughly researched before 

4WD testing is used for confirmatory testing. To this end, GM believes that EPA should 

continue with today’s practice of testing the same way the vehicle is certified by the 

manufacturer. 

4WD Dynamometer Facility Impacts: Implementation of 4WD dyno testing is a major facility 

impact, conservatively estimated to cost over $1 billion industry-wide, as detailed in the 

Alliance/Global comments. In addition, installation of the new dynos will adversely affect test 

throughput at a time when manufacturers need all of their test sites available to develop, validate 
Tier 3 Summary and Analysis of Comments

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and certify vehicles meeting the GHG/FE and Tier 3/LEV III requirements. The following 

outlines the facility impacts. 

4WD Facility Impacts to Conventional 75o F Test Sites: Implementation of 4WD dynos will 

have dramatic and adverse effects on emissions test facilities and OEM’s certification and 

development testing. Additionally, there is insufficient time to convert existing test sites to 4WD 

capability for the following reasons:

4WD dynos are more than twice the size of current 2WD dynos. 4WD dynos require very large 

pits compared with current, much smaller 2WD pits to house and service the dyno. These 4WD 

large pits require four times the surface area of today’s conventional 2WD pit, are twice as deep, 

require two egresses for safety, and require a huge inertial mass to mount the dyno to.

4WD dynos will require new building structures and utilities. Many OEM’s facilities were built 

in the 1970’s and were sized for much smaller twin roll water brake dynos. The much larger pit 

size required for 4WD dynos will easily exceed the available area on many of today’s test sites, 

and will clearly require much larger test sites. To accomplish this, existing sites will need to be 

expanded into neighboring cells, thereby significantly reducing the number of test sites available 

for Tier 3 certification and development testing. Given the increased stringency of the Tier 3 

regulations along with new GHG/FE standards, reducing the number of emissions test sites will 

definitely have an adverse impact on OEM’s ability to meet these new requirements.

Additionally, besides encroaching on adjacent test sites, these larger pits will also dramatically 

protrude out into routine vehicle movement lanes with safety egress stairs/hatches. When these 

hatches are open for dyno service or monthly calibration, vehicle traffic to adjacent test sites or 

evaporative sheds will be blocked, thereby adversely affecting emissions and fuel economy 

testing. Evaporative sheds need to be in close proximity to the chassis dynos due to the 40 CFR 

86.130-96 requirements that no more than 7 minutes time elapse from the end of chassis testing 

to the start of evaporative testing. 

4WD Facility Impacts to Climatic Test Chambers: Cold 20o F testing, hot 95o F SC03 testing, 

and the new A/C 17 testing all require specialized test chambers, and will also have to be 

updated with 4WD dynos. This is very problematic because these facilities are limited in 

number, and modifying them for 4WD testing will have a significant and adverse impact on 

current climatic emissions testing. The SC03 test sites are even more limited in number and 

4WD implementation is further complicated by the CFR required large road speed fan (wind 

tunnel), which is likely to cause additional structural issues and longer implementation time. 

4WD Construction, Implementation and Testing Down Time: We believe from start of 

construction to test site commissioning will take 1.5 years per test site, and as mentioned above, 

will need to be done in pairs of sites or more likely multiple test sites at any one time. The test 

sites removed from service for this construction are active certification and development test 

facilities, some of which are designed for specific vehicles like diesels. This will have an adverse 

impact on emissions testing capability. Additionally, because of this long downtime, 

manufacturers will only be able to convert a few sites at any given time. For a full line 

manufacturer, with dozens of test sites, this 4WD conversion will take a decade or more to 
Chapter 4: Proposed Vehicle Emissions Program

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complete. In fact, it is likely that 4WD dynos will force green field annexes or require the 

construction of new buildings. Manufacturers simply cannot afford to have test sites unavailable 

during this time when so much testing is needed for the development and certification of vehicles 

to meet the GHG/FE and Tier 3/LEV III standards. 

4WD Pits – Non Dynamometer Impacts: Installing these very large machines will undoubtedly 

have major effects on virtually all of the other equipment located in the test sites such as exhaust 

sampling systems (CVS/Tunnel/bulk stream and raw exhaust tubing), modal sample conditioning 

systems plus close coupled modal analyzers, overhead XY support systems to hang vehicle 

cooling fans, drivers aids, remote mixing tees, etc. It is likely that these will be replaced with the 

site construction or require modification. With such large scale changes, additional changes to 

computer programs to control these new devices will be needed and modifications (or likely 

replacement) of emissions benches will be needed as well. 

4WD Technology Not Well Understood: Many technical challenges still need to be resolved 

with the use of 4WD dynos. The dyno controls, set up parameters, calibrations, diagnostics and 

vehicle restraints all need to be studied. When 48-inch single roll dynamometers were adopted as 

part of the SFTP rulemaking, an extensive industry/government research program was launched 

to look into best practices and resolve any implementation and usage issues. Before 4WD dynos

can be used for certification testing, it is highly recommended that a similar program be initiated 

to understand 4WD dynos. 

4WD Dyno Adverse Impact on Long Term Testing Throughput: In addition to the impact on test 

throughput during the installation of 4WD dynos, it also takes much longer time to properly set 

up a vehicle on a 4WD dyno, which increases testing burden and slows down emissions testing 

on an ongoing basis. Please see the Alliance/Global comments for more detail. 

Recommendation: Given the magnitude of the impact on test facilities and test throughput, along 

with the adverse yet not fully understood impacts on fuel economy and GHG emissions that 

would require accurate test procedure adjustments, GM does not believe that it is appropriate 

make changes that would require 4WD dyno testing in the Tier 3 rulemaking, particularly since 

Tier 3 is an accelerated rulemaking focused on criteria emissions. Instead, GM recommends that 

the current practice of EPA performing confirmatory testing the same way the manufacturer did, 

whether 2WD or 4WDwd, continue, and that EPA work with industry to study 4WD dynos

further as detailed in the Alliance/Global comments. 

Organization: Mitsubishi Motors R&D America, Inc (MRDA)

As part of the Tier 3 NPRM, EPA has included language indicating they intend to begin 

Confirmatory Testing on 4WD dynos. If EPA conducts Confirmatory Testing on 4WD dynos, 

manufacturers will need to perform their certification and development tests on 4WD dynos to 

ensure proper correlation to EPA tests. Manufacturers will incur a massive cost burden to replace 

their 2WD dynos with 4WD dynos. Additional costs will be associated with the operation of the 

4WD dynos, the reduced testing throughput due to the time needed to upgrade facilities for 4WD 

dyno installation, as well as the longer vehicle set up time associated with 4WD dynos. Neither 
Tier 3 Summary and Analysis of Comments

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EPA nor Industry has completed analysis to verify that there is any air quality benefit to the 

overall cost of installing and using 4WD dynos as opposed to the 2WD dynos currently in use. 

The language in the Tier 3 NPRM states that manufacturers may continue to test on a 2WD 

dyno, ‘but only if this mode of operation does not decrease emissions or energy consumption 

relative to normal in-use operation’. (Page 30163 Federal Register / Vol. 78, No. 98 / Tuesday, 

May 21, 2013). This implies that manufacturers could be required to test on 4WD dynos. 

Mitsubishi Motors strongly recommends that an extensive test program be conducted to 

determine if there are both dyno and vehicle losses associated with testing on 4WD dynos. If 

4WD dyno testing is deemed necessary, Mitsubishi Motors believes that 2WD dyno testing 

would still be appropriate if the resulting data is accurately adjusted with a TPA. 

NPRM Comments: Based on the above information, we recommend that:

-EPA should continue to allow certification and fuel economy label testing to be conducted on 

2WD dynos.

-EPA should continue confirmatory testing the same way manufacturers perform their 

certification and fuel economy label testing.

-A TPA should be established to correlate the 2WD and 4WD dyno data.

-The language in 1066-410, stating a manufacturer may test on a 2WD dynamometer, ‘but only 

if this mode of operation does not decrease emissions or energy consumption relative to normal 

in-use operation’ should be eliminated. 

4WD Dyno Testing: EPA should continue to allow certification and fuel economy label testing 

to be conducted on 2WD dynos. EPA should continue confirmatory testing the same way 

manufacturers perform their certification and fuel economy label testing. Any inclusion of 4WD 

dyno testing into the Tier 3 program must be accompanied by a TPA to correlate the 2WD and 

4WD dyno data.

Organization: Volkswagen Group of America, Inc.

VW understands the need for a level playing field and a real world testing scheme. However, 

without the proper factors, testing vehicles on a 4WD dynamometer will not relate to the 1975 

testing methodology as required. VW requests that much more work be done before beginning 

any confirmatory testing on vehicles with a 4WD dyno. The requirement for FPA to test in the 

same manner as Manufacturers should be retained in Tier 3 final rules. Industry and EPA are 

testing vehicles to determine the proper methodology moving forward and VW supports this 

cooperative spirit. While we do hove 4WD dynos in our labs, the capacity may not be large 

enough to support testing a potential future W/ fleet. Pathways need to be available to continue

to test vehicles on 2WD dynos. 

New EPA testing protocols involving 4WD dynos and the apparent split from the agreement to 

perform testing in the manner of OEM test methods may lead VW to install more 4WD dynos. It 

is the unpredictable nature of these confirmatory tests that may lead to abandoning of 2WD 

dynos. As an estimate, it may cost $1.3 Million and approximately 1 year to convert a 2WD dyno 

cell. Typically only 1 cell at a time is completed to maintain throughput of testing. Should 

climatic elements or solar cells need to be installed, this price would increase. Thus, Industry 
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would need more than 90 days post Tier 3 signature for this conversion. We echo the Industry’s 

request to continue working with EPA on these issues. We also echo Industry’s comments that 

this program would potentially provide for factors for future technology vehicles, and not apply 

retrospectively to prior vehicles. We would continue to encourage EPA to engage with dyno 

manufacturers to develop proper dyno inertia error simulation procedures. 

Organization: Volvo Car Group

In addition, in order to enable future technology development it is critical that there be 

harmonization with CARB with respect to test criteria and design requirements. 

If manufacturers are required to utilize several different test procedures and to test against 

several different fuels, the lack of harmonization will generate unreasonable and unnecessary 

burdens that will impede the overall goal of facilitating low emission technology. 

During the workshops with EPA during 2012 and 2013, the Alliance has consistently and 

repeatedly shown that there is a FE decrease when the same 2WD-vehicle is run on 4WDcompared to 2WD dynamometer. 

VCG supports the concerns of the Alliance regarding these phenomena. At the EPA industry 

meeting on May 20, 2013, EPA expressed very clearly that a crucial aspect and goal for EPA is 

to achieve real world fuel consumption reductions. Part of this strategy is that EPA now has the 

ability to test on 4WD due to major investments. 

Through substantial investments, VCG has developed similar testing capability, but VCG would 

like to highlight several issues that have been identified with regard to this testing capability. 

- 4WD testing is more complex then 2WD. 

- The correlation between 2WD and real road performance has been thoroughly investigated over 

the past 20-30 years, yet more remains to be done. There are aspects of 4WD and actual road 

performance which now need to be investigated, understood and correlated. (Car fixation, tie

down etc.) 

- Possible interaction between vehicle and dyno not seen on road. 

Due to these issues, it would be premature to say that 4WD testing automatically represents real 

world fuel economy. Therefore, the investigation of a correlation factor to address the 4WD dyno 

aspects vs 2WD is essential. 

Dyno to road correlation may not be more accurate on 4WD dynos than on 2WD; it could just be 

different. The exact impact on FE for the all issues is not clearly known and this shows that 

further method development is needed for 4WD testing. VCG believes the EPA proposal is 

premature and that further analysis of 4WD dyno testing is necessary so all remaining issues are 

resolved. VCG would like to work with EPA to support this future work. 
Tier 3 Summary and Analysis of Comments

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Our Response:

We proposed that EPA may test vehicles with the capability of all-wheel drive operation 

with dynamometers operating in either two-wheel drive or four-wheel drive mode, regardless of 

the type of dynamometer that the manufacturer used for certifying the vehicle. However, the 

final regulations specify that we will conduct our testing using the same drive mode as the 

manufacturer. Vehicle manufacturers commented that differences in test results between a 

vehicle tested on a two-wheel drive and a four-wheel drive dynamometer might be due to 

differences in dynamometer characteristics more than in vehicle operation. Results of a 

government-industry study that tested vehicles on both two-wheel and four-wheel drive 

dynamometers indicated fuel economy differences in the range of ±4%, although the study was 

inconclusive with respect to the cause of the differences. Based on the results of this study, we 

will continue to test vehicles during confirmatory tests using the manufacturer’s dynamometer 

configuration for that vehicle, and that test will be the official certification result. We are, 

however, finalizing revisions to 40 CFR 1066.410(g) to clarify that we may also test the 

manufacturer’s vehicle in a different dynamometer configuration than what was used for 

certification testing for information-gathering purposes. If we decide to perform this testing, we 

will depend on the manufacturer to cooperate in reconfiguring the test vehicle for our testing. 

We will continue to investigate the effects of four-wheel drive dynamometers on emission results 

and will not rule out possible future test procedure changes that might require certification of, or 

allow EPA to perform confirmatory testing on, any vehicle on a four-wheel drive dynamometer.

4.7.2. Reduced Test Burden

What Commenters Said:

Organization: Ford Motor Company (Ford)

Where alignment cannot be achieved, it is important that mechanisms be provided to mitigate 

any unnecessary complexity and testing burden. For example, we agree with the proposed 

reciprocity provisions that will be crucial in helping manufacturers to manage the complexity in 

multiple certification testing and test procedures.

Our Response:

EPA has worked closely with CARB and vehicle manufacturers to limit test complexity and 

burden in the Tier 3 Final Rule. 

In addition, we are updating the regulatory provisions that allow manufacturers to omit testing 

for certification, in-use testing, and selective enforcement audits in certain circumstances. 

Sections IV.A.3, IV.B.6, and IV.G.3 of the Preamble describe how this applies for demonstrating 

that vehicles meet the Tier 3 PM standards. We are also allowing manufacturers to omit PM 

measurements for fuel economy and GHG emissions testing that goes beyond the testing needed 

for certifying vehicles to the Tier 3 standards. Requiring such measurement would add a 

significant burden with very limited additional assurance that vehicles adequately control PM. 
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We are also allowing manufacturers to ask us to omit PM and formaldehyde measurement for 

selective enforcement audits. If there is a concern that any type of vehicle would not meet the 

Tier 3 PM or formaldehyde standards, we will not approve a manufacturer’s request to omit 

measurement of these emissions during a selective enforcement audit.

The existing regulations have allowed for waived formaldehyde testing for gasoline- and dieselfueled vehicles. The Tier 3 NMOG+NOX emission standards are stringent enough that it is 

unlikely that vehicles will comply with the NMOG+NOX standards while exceeding the 

formaldehyde standards. We are therefore continuing this waiver practice, such that 

manufacturers of Tier 3 vehicles do not need to submit formaldehyde data for certification.

4.7.3. Miscellaneous Provisions

What Commenters Said:

Organization: General Motors LLC (GM)

GM is concerned with EPA’s definition of non-conformity of in-use vehicles under Tier 3 when 

vehicles are tested in-use. The non-conformity definition is a critical component of the 

stringency of the regulation. GM supports the Tier 3 regulation based on the premise that Tier 3 

and LEV III are of equal stringency as well as harmonized. The industry widely recognizes that 

emissions control systems must be engineered with a degree of compliance margin to assure inuse compliance. EPA conformity language differs significantly from the conformity language of 

CARB. CARB regulations for LEV III recognize the average emissions test results of each 

constituent as a method to evaluate conformity of a test group. Average emissions are a sound 

statistical criterion upon which GM and other manufacturers can base compliance margins. 

EPA’s criteria are potentially subjective and statistically undefined, particularly given the 

relatively small sample sizes used for in-use test programs. Therefore, GM is concerned about 

both the stringency of Tier 3 and the ambiguity of the compliance definition, and would like to 

work with EPA to ensure an approach that is statistically sound and harmonized with LEV III. 

Our Response:

With the exception of addressing in-use fuel sulfur implications to emissions discussed in 

Chapter 4.1.5.12 of this Summary and Analysis of Comments document, the IUVP requirements 

and determinations of conformity are outside of the Tier 3 rule. EPA is committed to working 

with industry to address Tier 3 related in-use concerns that may arise in the future. 

4.8 Leak Standard Comments

4.8.1. Introduction of New Leak Standard

What Commenters Said:
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Organization: Michigan Department of Environmental Quality (MDEQ)

The MDEQ, Air Quality Division supports the more stringent evaporative, leak and refueling 

emissions standards, as well as the new test procedures described in the proposed rule. Control 

of these significant sources of volatile organic compounds, particulate matter, and toxic air 

contaminants have been demonstrated to be cost effective and attainable. California appears to 

have already implemented a program with many similar requirements, showing that the limits 

can be met. 

Organization: National Association of Clean Air Agencies (NACAA)

Evaporative Emission Standards — EPA proposes new evaporative emission standards to reduce 

total evaporative emissions from all gasoline-powered highway vehicles to near-zero levels. The 

program would require new evaporative emission control technology on new vehicles as well as 

system design improvements to achieve improved in-use system performance and extend useful 

life. The proposed approach also introduces a new canister leak emission standard and would 

apply California’s onboard diagnostic requirements nationwide. NACAA endorses these 

proposed requirements.

Organization: California Air Resources Board (CARB)

CARB supports the proposed evaporative leak test and standard, and believes that the leak test 

program will be effective in reducing in-use evaporative emissions. Accordingly, CARB intends 

to propose alignment with this proposal once the Tier 3 program is finalized. 

Our Response:

EPA acknowledges the support of State and local governments for the new leak standard 

as well as California’s intent to propose the new standard for adoption into their requirements, 

thereby maintaining a harmonized vehicle program for 50 States.

4.8.2 Nature and Scope of the Requirement

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA asked for comment on a third option that would require that a manufacturer meet the Tier 3 

evaporative emissions standard on 20 percent of its fleet less than 6,000 pounds GVWR and also 

meet the leak check standard on those vehicles. We support this option and appreciate that EPA 

understands our concerns. 
Chapter 4: Proposed Vehicle Emissions Program

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We agree that manufacturers could meet the leak check standard on 20 percent of their MY 2017 

fleet; however, since these are independent requirements, there is no reason that manufacturers 

need to overlap the vehicles meeting Tier 3 evaporative emission standards with vehicles 

meeting the leak check standard. 

Our Response:

EPA concurs and has incorporated this MY 2017 flexibility into the final Tier 3 rule.

4.8.3. Leak Test Procedure

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

The connection point for most IUVP vehicle leak testing will be located at or near the purge 

valve. This will test the complete fuel system. For leak testing conducted in this manner only one 

test should be required. No additional testing is required to test the fuel cap. Also, for dual tank 

vehicles that have the vapor space of both tanks connected, repeat testing should not be required.

Our Response:

EPA asked the Alliance for data to support this comment and did not receive a 

response

47. Therefore we are relying on the laboratory data that was gathered by EPA48

 which 

was referenced in the NPRM Appendix to the RIA. This EPA report shows that location of test 

connection points does matter for leak detection depending on where the leak is located. The leak 

standard requires two or more test points depending on the fuel evaporative system 

configuration.

What Commenters Said:

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Assuming implementation of the OBD regulation changes proposed in Section IV.C.5.d, EPA is 

proposing an optional approach to a portion of the leak emission test procedure discussed in 

Section IV.C.5.c. This optional testing approach would be included in the proposed IUVP/IUCP 

testing program for the leak emission standard, but would not be used for certification testing for 

 

1

Passavant, G. (June 2013) EPA and Auto Industry Meeting Related to Tier 3 Evap and OBD NPRM. 

Memorandum to the docket

48 Smith, P. and Passavant, G., “Recommended Test Procedure and Supporting Testing Data for the Evaporative 

Emissions Leak Test”, December 2013.
Tier 3 Summary and Analysis of Comments

4-415

the leak emission standard. It would be considered an approach which could be used by the 

manufacturers to assess compliance with the leak emission standard. EPA could also use this 

procedure for conducting assessments and asks for comment on using this procedure for 

compliance purposes with a 0.02 inch cumulative equivalent diameter orifice standard.

We support this optional approach that would allow manufacturers to use the OBD evaporative 

system leak detection hardware in lieu of running the stand alone in-use leak test. This option 

allows manufacturers to rely on the OBD system, which is designed for this purpose, as the 

primary compliance method, thereby reducing and simplifying testing requirements, as well as 

reducing test time and costs. 

Our Response:

EPA concurs and this option is part of the final Tier 3 rule. 

4.8.4. Certification and Compliance

What Commenters Said:

Organization: National Association of Clean Air Agencies (NACAA)

Also related to evaporative emissions, with respect to the In-Use Verification Program (IUVP) 

requirements for the leak emission standard, EPA notes in the proposal that fuel and evaporative 

control system leaks are influenced to a significant degree by age as well as design and other 

factors. The agency, therefore, seeks comment on whether to extend leak emission IUVP testing 

to vehicles beyond the four-year age point, perhaps to six or eight years. Because of the 

importance of in-use confirmatory testing for older vehicles, NACAA believes EPA should 

extend testing beyond the four-year point. 

Organization: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA asks comment on the viability of extending leak emission IUVP testing beyond the nominal 

four year point.

We do not support this change at this time. As EPA recognizes in the preamble, “in the past, 

manufacturers have expressed concern about the implications of testing older vehicles and about 

finding vehicles still within their warranty and recall liability periods” [78 FR 29905]. These 

issues continue to be problematic. In fact, obtaining vehicles at the required high mileage point at 

four years under the current IUVP test can be difficult. Any changes to vehicle age should be 

considered as a broader and separate IUVP regulatory action that would include reductions in 

test burden along with consideration of procurement of older vehicles still within warranty. 
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Industry is opposed to evap leak testing of customer vehicles at 6 to 8 years of age. Requiring 

evap testing beyond the current 4 year IUVP point would require a second evap only leak test 

fleet of vehicles. This would be costly and represent a new burden to industry. 

Organization: California Air Resources Board (CARB)

The NPRM proposes additional measures to identify evaporative leaks on in-use vehicles based 

on studies performed by the Coordinating Research Council and Colorado Department of Public 

Health and Environment. Specifically, the NPRM proposes adding a test procedure to the IUVP 

focused on testing a broader sample of, fuel/evaporative systems leaks in in-use vehicles. 

Moreover, the NPRM proposes the addition of an IUVP evaporative leak check requirement 

beginning with 2018 model year vehicles. This requirement would be included in the IUVP’s 

low and high mileage tests for any volatile fuel powered vehicle (except diesel and natural gas) 

with a requirement that there be at least one representative vehicle for each 

evaporative/refueling/leak family evaluated at each year point. EPA is proposing this approach in 

lieu of creating a new set of requirements which would require a separate set of vehicles to be 

procured for testing. In addition, the NPRM is considering extending the age point for leak 

emission testing for IUVP beyond the current four year test point (e.g., testing vehicles six to 

eight years old) to better assess aged vehicles for evaporative leaks. 

U.S. EPA is also proposing to conduct an evaporative leak test on vehicles that are 6 to 8 years 

old. Although this is doable for IUVP, the challenge will occur if enough vehicles fail the leak 

check for a given test group and the manufacturer must then conduct an In-Use Confirmatory 

Program. Under an In-Use Confirmatory Program, the manufacturer must procure ten properly 

maintained and used vehicles which creates a challenge because many of these vehicles will be 

out of warranty, sold to a second owner and/or operated beyond 75 percent of the certified useful 

life and may not be properly maintained. Accordingly, CARB recommends that U.S. EPA 

include language to require testing on vehicles no more than 6 years after the certified model 

year and within 75 percent of the useful life mileage. For example, a manufacturer would be 

required to conduct evaporative leak testing on 2015 MY vehicles within 75 percent of the useful 

life mileage and before the end of the 2021 calendar year. 

Our Response:

EPA has taken the conflicting comments into consideration and will not be including an 

extension of the IUVP age in this rule. Given the benefits which can be achieved through 

extending of the IUVP testing age to 6-8 years or more, our intention is to look at this more 

closely in the future. At that time EPA will be able to consider the issues raised above. EPA 

notes that with the useful life for emissions certification levels extended to 15 years and 150,000 

miles, 75% is now over 110,000 miles and 11 years which is far beyond the 6-8 years identified 

in the solicitation for comment, we would expect manufacturers to be able to find vehicles in 

these age ranges suitable for IUVP testing.
Tier 3 Summary and Analysis of Comments

5-1

5 Tier 3 Fuel Sulfur Program

What We Proposed:

The comments in this chapter correspond to Section V of the preamble to the proposed 

rule and address the economic impacts of the program. A summary of the comments received 

and our response to those comments are located below.

5.1. Proposed Tier 3 Gasoline Sulfur Standards

What Commenters Said:

Commenter: Chevron Products Company

If EPA does proceed with reducing gasoline sulfur content, we generally agree with the 

mechanism of the program outlined in the proposal. We agree with maintaining the structure of 

the current Tier 2 gasoline sulfur program and extending that structure to the new Tier 3 

program. The use of an annual average standard per refinery, accompanied by separate 

maximum per gallon cap standards at the refinery gate and downstream of the refinery, is the 

appropriate way to implement the new program. This structure has worked well under Tier 2 

and provides consistency for regulated parties as they transition to Tier 3. 

Commenter: Manufacturers of Emission Controls Association (MECA)

MECA believes that a 10 ppm average gasoline sulfur standard with a gasoline sulfur cap of no 

higher than 50 ppm provides the refining industry with an adequate, cost-effective compliance 

pathway. 

Our Response:

The final Tier 3 fuel program consists of a 10 ppm refiner annual average sulfur standard 

(which allows a refiner to average over all of its refineries), with an 80 ppm refinery per-gallon 

cap and a 95 ppm downstream cap. Please see Chapter 5.1.1 for more discussion on the 10 ppm 

annual average sulfur standard, and Chapter 5.1.2 for more discussion on the per-gallon sulfur 

caps.

5.1.1. Annual Average Sulfur Standard

5.1.1.1. General (incl. General Support & Opposition for 10 ppm Sulfur Standard)

What Commenters Said:

Support
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5-2

Commenter: American Coalition for Ethanol (ACE)

We support EPA’s proposal to ensure that gasoline and ethanol-blended gasoline contain no 

more than 10 parts per million (ppm) sulfur on an annual average basis by January 1, 2017. 

Commenter: American Thoracic Society

We are particularly supportive of the proposal to reduce the fuel sulfur content from 30 parts per 

million to 10 parts per million.

The policy will also have the double benefit of allowing auto manufacturers to use improved 

technology in catalytic converters and other pollution control technology to make future vehicles 

emit even less pollution.

Commenter: Chrysler Group LLC

In the April 2013 Tier 3 hearings in Philadelphia and Chicago, Chrysler testified in support of 

the Environmental Protection Agency’s (EPA’s) lowering the sulfur content of market fuel 

gasoline. 

Recommendation: Chrysler recommends that EPA adopt the 10 ppm sulfur market fuel standard.

Commenter: Clean Air Council

More specifically, the proposed rules would reduce the refinery annual average sulfur limit in 

gasoline from 30 parts per million to 10 parts per million, which is a 66 percent reduction.

The Council applauds EPA’s proposed reduction of the annual average sulfur limits from 38 to 

10 parts per million. 

Commenter: Ford Motor Company (Ford)

The proposed Tier 3 emissions standards program are cited by the EPA as a “systems approach 

to reducing vehicle-related exhaust and evaporative emissions by addressing the vehicle and fuel 

as a system.” We agree with the EPA’s identification of the need to reduce sulfur levels in 

market fuel to 10 parts per million (ppm). 

Commenter: Michigan Department of Environmental Quality (MDEQ)

The MDEQ, Air Quality Division is very supportive of the proposal to reduce sulfur 

concentrations in gasoline to 10 parts per million (ppm) on an annual average basis by January 1, 

2017. 

Commenter: Truck and Engine Manufacturers Association (EMA)
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5-3

In addition, EMA and its members have also been long-time proponents of high quality fuels, 

and, as such, we are advocates for the removal of sulfur from both gasoline and diesel fuel.

Commenter: Union of Concerned Scientists (UCS)

The oil industry, which stands alone in its opposition to the Tier 3 program, would have you 

believe that these standards are unnecessarily burdensome – that the challenge is too great, and 

the costs are too high. This is simply not true. We have the technical capacity to meet these 

standards. Scientists and engineers in the U.S. and around the world are already achieving the 

goals of these standards, and doing so in a cost-effective way. And that is why the standards are 

supported by health groups, labor organizations, the environmental and faith communities, the 

auto industry, and state and local officials, among others. Don’t let the oil industry’s misleading 

analysis stand in the way of improving public health for everyone.

Our Response:

We appreciate the comments and, as previously stated, are finalizing an annual average 

sulfur standard of 10 ppm. For more information on the level of the standard, please see Chapter 

5.1.1.2, below.

5.1.1.2. Level of the Standard

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

As EPA has noted, sulfur is a catalyst poison and precludes the full functioning of catalytic 

exhaust after-treatment systems. Indeed, EPA assumed the existence of 10 ppm average sulfur 

gasoline when it determined the feasibility of the Tier 3 emission standards EPA’s new study of 

the effects of sulfur on vehicle emissions found that there are strong benefits when reducing 

sulfur from 28 ppm to 5 ppm, confirming earlier studies. The agency noted in the Regulatory 

Impact Analysis that lower levels of sulfur can lead to “significant reductions” of emissions in 

the in-use fleet.

The specific catalyst damage caused by sulfur and the concurrent reduction in the functioning 

and efficiency of emission control equipment has been assessed in a number of studies, most 

recently in the EPA study noted above. EPA noted that the relative effectiveness of NMOG and 

NOx control are constrained by the sulfur level of the fuel, and found that there is clear damage 

to the catalysts from sulfur exposure, and further found that catalysts never fully desulfurize, 

even after a clean out procedure, as long as there is sulfur in the fuel.

Prior sulfur studies have also assessed the effects of sulfur on vehicle/fuel systems. The Ball 

study found that 3 ppm sulfur fuel would reduce NOx emissions by 40% compared to the 33 

ppm fuel, and/or allow savings because lower levels of precious metals would be required in the 
Chapter 5: Tier 3 Fuel Sulfur Program

5-4

catalyst. In addition, the Association for Emissions Control by Catalyst (AECC) study found 

“The promising NOx adsorber technology that diesel and lean burn engines need requires sulfur 

levels significantly below 10 ppm. This will avoid compromising the lower fuel consumption 

and CO2 emissions by requiring frequent regeneration to remove the sulfur that is clogging the 

NOx adsorption capacity”.

The 10 ppm refinery average and a reduced retail cap are necessary to optimize and maintain the 

function of engine and exhaust after-treatment technologies. During the combustion process, 

sulfur, in both elemental and in compound forms, is present in the exhaust stream and is readily 

deposited on the surface of exhaust after-treatment devices, including oxidation and reduction 

catalysts as well as NOx adsorption components. It is on these surfaces precious metals are 

placed by design to provide the conversion sites for the chemical reaction which converts 

pollutants to harmless gases. Surface contamination with sulfur inhibits the conversion efficiency 

of exhaust after treatment components. In fact, even low levels of sulfur impede the function of 

these devices especially if they were previously subject to higher sulfur fuels. 

While it is possible to dislodge the embedded sulfur through various mechanisms which raise the 

exhaust gas temperature sufficiently to “burn off” such deposits, in practice, it is far more 

difficult to accomplish this removal. This is especially true given the nature of emerging, higherefficiency combustion technologies required under the new CAFE/GHG standards, which extract 

more energy from the fuel. Reduced sulfur is necessary not only to help catalysts function better, 

but also to prolong their life and to achieve a 25% increase in catalytic converter durability 

(120K-150K miles useful vehicle life).

Commenter: National Association of Clean Air Agencies (NACAA)

Tier 3 Vehicle Technologies and Gasoline Are Already Available: Not only is Tier 3 

tremendously effective from an air quality perspective — low in cost, high in cost effectiveness 

and good for the economy — it is feasible today. EPA’s proposed Tier 3 vehicle tailpipe 

standards are modeled on California’s LEV III program. The potential technologies for this 

program are consistent with, and almost entirely the same as, those on today’s California’s 

vehicles, including precious metal catalyst loading, optimized close-coupled catalysts, secondary 

air injection pumps and evaporative control systems. 

Further, California’s gasoline already achieves 10-ppm sulfur on average. Finally, gasoline in 

other nations, including those in the European Union and Japan, is subject to a 10-ppm cap. 

China has also adopted requirements for 10-ppm sulfur, to take effect in 2017. 

Commenter: Natural Resources Defense Council (NRDC)

To achieve the maximum cost-effective pollution reductions, the agency must consider the 

interaction between gasoline sulfur levels and vehicle pollution control equipment because sulfur 

buildup can limit exhaust catalysts effectiveness and shorten its useful life. 

Commenter: Union of Concerned Scientists (UCS)
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5-5

This will be particularly important over time as new vehicle greenhouse gas standards begin to 

reduce exhaust temperatures, which can degrade catalytic converter performance. Reducing 

gasoline sulfur can help offset this problem. UCS worked hard to secure the greenhouse gas 

standards, and we are again committed to achieving the lower sulfur standards needed to protect 

public health, and ensure the efficiency of the greenhouse gas standards as well.

Commenter: Flint Hills Resources, LP (FHR)

As a member of the American Fuel and Petrochemical Manufacturers (AFPM) trade association, 

FHR for the most part supports the comments submitted by AFPM, including opposition to a 

more stringent average gasoline sulfur standard, due to inadequate technical justification and 

negligible environmental benefits. Additionally, FHR is submitting the attached comments to 

emphasize, or perhaps clarify, our position related to certain detailed aspects of the proposal. 

Commenter: Irving Oil Terminals Inc.

Assuming that EPA plans to adopt a reduced sulfur standard for motor gasoline, that standard 

should be no more stringent than an annual average of 10 ppm sulfur. EPA has already 

determined that such a standard is sufficient to enable vehicles to reach the proposed Tier 3 

standards. Moreover, a standard below 10 ppm would be too difficult and costly to meet. For 

example, EPA estimated that the cost of sulfur control compliance with a standard of 5 ppm 

sulfur would be at least 50 percent higher than compliance with the proposed 10 ppm standard —

an unnecessary substantial financial burden. In addition, industry studies have estimated that a 

standard below 10 ppm would result in substantial refinery shutdowns and supply disruptions. 

Commenter: Countrymark; Small Business Refiners (SBRs)

As we examined the proposed rule, we found no technical support for the recommended limit of 

10 ppm. The rule suggests that 10 ppm is a good break point where sulfur removal is cost 

effective, but no data was provided to support this position. In addition, no commercial data 

could be found by searching literature to support this position. CountryMark requests why the 

limit is not 15 ppm to match diesel sulfur content, if the limit has to be changed. 

We believe that the present sulfur levels are even lower than the above data because 1) it 

includes small refiner gasoline which had a higher standard until 2011 and was estimated by 

DOE to be approximately 11.9% of the gasoline supply in 2010 and 2) the above data represents 

summer gasoline which would overstate the annual sulfur level as low sulfur butane is added to 

winter gasoline in levels of 3-4 volume percent. 

Pennsylvania Department of Environmental Protection (DEP )

The EPA should fully explain the justification for choosing a fuel sulfur limit of 10 ppm.

The EPA should better explain why 10 ppm was chosen. The EPA explained why a lower level 

was not chosen, but did not fully explain why a higher level was not chosen. 
Chapter 5: Tier 3 Fuel Sulfur Program

5-6

Commenter: Sierra Club

EPA has provided robust evidence that regulating fuel quality, and specifically, reducing the 

sulfur content of fuels from 30 ppm to 10 ppm pursuant to its Section 211 authority, will obtain 

significant pollution reductions that could not otherwise be achieved by setting direct pollution 

control standards for tailpipe exhaust and evaporative emissions alone. For example, in the 

context of NOx reductions under the proposed rule, EPA’s studies conclude that “the impact of 

gasoline sulfur poisoning on exhaust catalyst performance and the relative stringency of the Tier 

3 standards, particularly for larger vehicles and trucks, when considered together make a 

compelling argument for the virtual elimination of sulfur from gasoline ... a gasoline sulfur 

standard of 10 ppm ... represents the highest level of gasoline fuel sulfur that will allow 

compliance with a national fleet average of 30 mg/mi NMOG + NOx.” As such, EPA has 

appropriately proposed direct pollutant emission limitations and fuel quality standards to set a 

standard that is “achievable” and that meaningfully addresses the problems posed by motor 

vehicle pollution. (42)

Moreover, EPA’s studies also demonstrate gasoline sulfur content controls are a necessary 

component to ensuring NOx reduction feasibility under the proposed rule. EPA’s studies 

conclude that “1) reversible sulfur loading is occurring in the existing Tier 2 vehicle fleet and has 

a measurable effect on emissions of NOx, hydrocarbons, and other pollutants; 2) the 

effectiveness of high speed/load procedures in restoring catalyst efficiency is a function of fuel 

sulfur content; and 3) reducing fuel sulfur levels from 28 ppm to 5 ppm is likely to achieve 

significant reductions of emissions of NOx, hydrocarbons, and other pollutants of interest in the 

in-use fleet.” EPA also provides that: [T]he impact of gasoline sulfur on NOx emission control of 

catalysts in the fully-warmed-up condition is particularly of concern for larger vehicles. 

Manufacturers face the most significant challenges in reducing cold-start NMOG emissions for 

these vehicles. Because of the need to reach near-zero NOx levels, any significant degradation in 

NOx emissions control over the useful life of the vehicle would likely prevent some, if not most, 

largest vehicles from reaching a combined NMOG + NOx low enough to comply with the 30 

mg/mi fleet-average standard ... [a]ny degradation in catalyst performance due to gasoline sulfur 

would reduce or eliminate the margin necessary to ensure in-use compliance with the proposed 

Tier 3 emissions standards. 

Based on studies, EPA concludes that “A gasoline sulfur standard of 10 ppm also represents the 

highest level of gasoline fuel sulfur that will allow compliance with a national fleet average of 30 

mg/mi NMOG + NOx.” 

EPA adequately demonstrates that the 10 ppm gasoline sulfur content standard is feasible. EPA 

makes the case that currently available technologies, some of which are employed in U.S. 

refineries are achieving significant reductions in gasoline sulfur/

_______________________________________

42 It is important to note that EPA is proposing an average sulfur standard of 10 ppm. However, the 

actual sulfur content of fuel can vary substantially, based on variations in refinery operations and 

contamination from gasoline being transported through pipelines to its final destination. Automakers must 

then design vehicles to function with higher-sulfur gasoline. In order to give certainty to automakers 

designing vehicles and to ensure emissions reductions, setting caps on per-gallon sulfur content is critical. 

Currently, sulfur is capped at 80 ppm per gallon at the refinery gate and 95 ppm per-gallon downstream. 
Tier 3 Summary and Analysis of Comments

5-7

In this proposal, EPA is proposing two options: keep the per-gallon caps the same, or lower them to 50 

ppm at the refinery gate and 65 ppm downstream in 2020, to allow small refinery provisions to take 

effect. We urge EPA, as it lowers the average sulfur standard from 30 ppm to 10 ppm, to also lower the 

per-gallon sulfur caps to at least 50 ppm at the refinery gate and 65 ppm downstream. Lowering the pergallon caps will allow automakers to employ additional advanced vehicle technologies that can increase 

vehicle efficiency and lower emissions, while still allowing compliance flexibility for refiners.

Commenter: Emissions Control Technology Association (ECTA)

We agree with EPA’s conclusion that the average sulfur content of gasoline must be reduced 

from 30ppm to 10ppm to ensure the effectiveness of catalysts necessary to reduce emissions. 

EPA concludes that: “...the impact of gasoline sulfur poisoning on exhaust catalyst performance 

provides a compelling argument, particularly for larger vehicles and trucks, that these vehicle 

standards would be achievable only with a reduction of gasoline sulfur content from the current 

30-ppm average down to a 10-ppm average’.

Section III of the FR Proposed Rule is an excellent review of the state-of-the-art understanding 

of sulfur impacts on gasoline vehicle emissions. Further, achieving the Tier 3 levels of emissions 

in all vehicle classes will require this level of sulfur. The description in Section IV of immediate 

reductions in fleet criteria pollutants when pump fuel sulfur is reduced to <10 ppm is new, 

relevant, and well conducted. We cannot add to these thorough analyses, but strongly endorse 

them. 

Let me get technical. The fundamental catalyst problem we are talking about here is that sulfur 

is extremely surface active. It’s unique to these types of chemicals. It absorbs readily on active 

catalyst sites, blocking the amazing action we need and want to clean up toxins. Surface active 

species are essentially -- are especially critical in low concentration ranges where most of the 

valuable active sites are sulfur poisoned in the sub 20 ppm sulfur range, depending on catalyst 

design. Dropping from 30 to 10 ppm sulfur can have a huge impact on catalyst performance and 

durability because of this fundamental physical chemistry behavior. 

Commenter: Robert Bosch GmbH, Gasoline Systems, Germany

The limits for sulfur compounds needs to be fixed at least at the lowest level for sulfur in the 

respective liquid fuel (diesel/gasoline) due to the same requirements for the exhaust gas 

treatment systems, no matter what fuel is used. 

Our Response:

As explained in Sections II and V.M of the preamble to the final rule, we are lowering the 

existing gasoline sulfur standards under section 211(c)(1), because emission products of gasoline 

with current levels of sulfur cause or contribute to air pollution which may reasonably be anticipated 

to endanger public health or welfare, and because emission products of gasoline with current levels 

of sulfur will impair to a significant degree the emissions control device or systems on the vehicles 

subject to the final Tier 3 standards. As discussed in Section II.B of the preamble to the final rule, 

control of gasoline sulfur to 10 ppm will lead to significant reductions in emissions of these 
Chapter 5: Tier 3 Fuel Sulfur Program

5-8

pollutants, with the benefits to public health and welfare significantly outweighing the costs. As 

also discussed in Chapter 4 of this Summary and Analysis of Comments document (and further 

in Section IV.A.6 of the preamble to the final rule and Chapter 5 of the RIA), we believe that a 

standard of 10 ppm is appropriate, and when combined with the advances in emissions control 

technologies, will be sufficient to meet the Tier 3 emissions standards. We also believe that the 

10 ppm annual average standard will bring significant immediate benefits by reducing emissions 

of the existing fleet. This sulfur standard is also feasible and is the level which appropriately 

balances costs with the emission reductions that it provides and enables.

With regard to the comment on why a higher sulfur level was not chosen, we note that the 

feasibility of the 30 mg/mi NMOG+NOx fleet average depends on exhaust catalyst systems that 

require gasoline with average sulfur levels of 10 ppm or less. Further, annual average sulfur 

levels greater than 10 ppm would significantly impair the emission control technology that we 

expect will be used to meet the Tier 3 standards and to ensure in-use compliance over a vehicle’s 

useful life. This is particularly a concern for some larger vehicles that will need to reduce NOx 

to near-zero levels, due to greater difficulty in reducing cold-start NMOG, in order to meet a 

combined NMOG+NOx standard. As discussed in Section IV.A.6 of the preamble, increasing 

gasoline sulfur to 20 or 30 ppm would make it impossible for vehicle manufacturers to meet the 

Tier 3 standards. Achieving Tier 3 standards would require offsetting the resultant higher 

emissions but EPA is not aware of existing technology or developing technology that could 

address these higher emissions when taking into consideration the entire vehicle fleet. A higher 

average sulfur standard would also forego the very large immediate reductions from the existing 

fleet.

We also disagree with the comment that we did not provide data to support our position 

that a sulfur standard below 10 ppm is not cost-effective. As discussed in Section V.B of the 

preamble to the Tier 3 final rule, we also do not believe a sulfur standard lower than 10 ppm is 

necessary to enable vehicles to meet the Tier 3 standards. While reducing sulfur below 10 ppm 

would further reduce vehicle emissions and allow the Tier 3 vehicle standards to be achieved 

more easily, we believe that a 10 ppm average standard is sufficient to allow vehicles to meet the 

Tier 3 standards given the significant challenges associated with reducing sulfur below 10 ppm. 

Our analysis shows that a 10 ppm annual average is sufficient to enable vehicles to reach the Tier 

3 standards. Consequently, while reducing sulfur levels further would continue to yield 

reductions from the in-use fleet, they would not be necessary to enable the new Tier 3 vehicle 

standards to be met. Further, as explained in Section V.L of the preamble, while sulfur levels 

would continue to reduce emissions from the existing fleet, reducing sulfur further below 10 ppm 

becomes increasingly difficult and costly. FCC naphtha is very rich in high-octane olefins. As 

the severity of desulfurization increases, more olefins are saturated, further sacrificing the octane 

value of this stream and further increasing hydrogen consumption. Making up for this lost 

octane represents a significant portion of the sulfur control costs. Furthermore, as 

desulfurization severity increases, there is an increase in the amount of sulfur removed (in the 

form of hydrogen sulfide) which recombines with the olefins in the FCC naphtha, thus offsetting 

the principal desulfurization reactions. There are means to deal with the recombination 

reactions, but they result in even greater capital investments. In addition, while FCC gasoline 

contributes the majority of sulfur to the finished gasoline, as the sulfur level drops below 10 

ppm, the sulfur level of the various other gasoline streams within the refinery also become 
Tier 3 Summary and Analysis of Comments

5-9

important. Any necessary treatment of these additional streams increases both capital and 

operating costs.

U.S. refineries are currently in different positions technically and financially, and vary 

greatly in size. It can be less costly per gallon for some to get down to 10 ppm, so a 10 ppm 

average standard plus the flexibility afforded by the averaging, banking, and trading (ABT) 

program helps those refineries with very high costs. However, if the gasoline sulfur standard 

were lower, this would essentially end the ability of refiners to average sulfur reductions across 

their refineries, because there would not be enough opportunity to generate credits at levels much 

below 10 ppm. Further, as discussed in detail in Chapter 5 of the RIA, our analysis shows that 

sulfur control costs for refineries to meet a standard below 10 ppm could be on the order of two 

times more costly per ppm-gallon of gasoline sulfur reduced. A standard below 10 ppm could 

also be cost-prohibitive for more challenged refineries. Lastly, such a standard would also 

introduce additional costs to address the contribution to gasoline sulfur from gasoline additives, 

transmix, ethanol denaturants, and contamination in the distribution system.

Therefore, we believe that the 10 ppm annual average standard will help reduce current 

levels of sulfur that contribute to ambient levels of air pollution that endanger public health and 

welfare. It will also help prevent significant impairment of the emission control systems 

expected to be used in Tier 3 technology, significantly improve the efficiency of emissions 

control systems currently in use, and continue prevention of the substantial adverse effects of 

sulfur on the performance of vehicle emissions control systems. 

5.1.1.3. Vehicle Need/In-Use Benefits/GHG & CAFE

What Commenters Said:

Commenter: Advanced Engine Systems Institute (AESI)

As MECA has pointed out, compliance with the proposed standards is both technically feasible 

and cost-effective. However, as automakers deploy new and increasingly more efficient engines 

that produce less waste heat, the catalysts and other emissions control devices that now depend 

on using that excess heat to burn off damaging deposits will be significantly more vulnerable to 

sulfur poisoning and degradation, unless the amount of sulfur in fuel is simultaneously reduced 

to 10 parts per million or lower, as has been proposed.

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA acknowledges that reducing the sulfur content of gasoline to a 10-ppm annual refinery 

average is a vital component of the proposed rule. We agree. In fact, our ability to effectively 

meet the Tier 3 requirements depends on EPA reducing the sulfur in market fuel. Sulfur inhibits 

the catalytic converter’s ability to reduce vehicle emissions, so lower sulfur at the pump means 

fewer exhaust emissions in the air. And because lower sulfur reduces emissions from all 
Chapter 5: Tier 3 Fuel Sulfur Program

5-10

vehicles, the proposed sulfur reductions would achieve Day One benefits, immediately reducing 

emissions from every gasoline-powered vehicle on our roads, no matter how old. 

Support for Reductions in Tier 3 Market Fuel Gasoline Sulfur Standards: There are a number of 

issues related to market gasoline which are appropriately within the scope of the Tier 3 final rule, 

or a supplemental Tier 3 rulemaking. Such issues are integral to product design, planning, and 

implementation for all OEMs because vehicles and fuels are a system and clean, efficient 

operation of vehicles is limited by the fuels on which they depend. EPA itself echoed this 

concept in the NPRM Preamble noting that its proposal promotes a “systems approach to 

addressing the impacts of motor vehicles and fuels on air quality and public health’ (33). 

We agree with changing the first of three prongs of the Tier 2 market sulfur standards, the annual 

refinery average, from 30 ppm to 10 ppm. As EPA notes, there is ample evidence that sulfur is a 

catalyst poison, and there is a “compelling case” that significant reductions of sulfur are needed 

to meet increasingly stringent criteria pollutant requirements in the Tier 3 standards. The Agency 

noted that “because any amount of sulfur in fuel can [damage catalysts] the lower sulfur the 

better.” Sulfur reduction also supports increased vehicle efficiency to meet CAFE/GHG 

requirements. 

To be clear, automakers support EPA reducing the annual refinery average for gasoline sulfur 

from 30 to 10 ppm. 

OEMs require further reductions of the content of sulfur in gasoline, to continue to innovate and 

meet important environmental goals included in Tier 3 and CAFE/GHG requirements. Based on 

recent projections, the internal combustion engine (ICE) will continue to be the predominant 

technology through the next several phases of vehicle emission standards, at least until 2025. 

Thus, it is increasingly important to determine the best way for the internal combustion engine to 

meet more stringent emission and fuel efficiency requirements. 

Automakers support EPA in its efforts to reduce the sulfur content of fuel, and the 10 ppm 

annual average in the proposed rule is a step in the right direction.

We support the 10 parts per million average and a low cap for sulfur and gasoline. 

In addition to needing ultra-low sulfur fuel to achieve the proposed emission standards, ultra-low 

sulfur fuel is also critical to auto manufacturers’ effort to meet the combined 54.5 miles per 

gallon fuel economy and greenhouse gas emission standards by 2025. And, most importantly, 

the ultra-low sulfur fuel will provide immediate and substantial public health benefits from the 

existing fleet of nearly 250 billion vehicles on the road today. 

According to the National Association of Clean Air Agencies, the impact on the fleet is 

equivalent to taking over 30 million vehicles off the road. And today vehicles are lasting longer, 

and the average age of all vehicles on the road is 11 years. While the proposed standards will be 

another great step in reducing the fleet’s emissions, it will take time for fleet turnover to fully 

realize the benefits. In the meantime, the ability to immediately and directly reduce emissions 

from the vehicles on the road today by reducing sulfur and gasoline cannot be matched. 
Tier 3 Summary and Analysis of Comments

5-11

EPA acknowledges that reducing the sulfur content of gasoline to 10 part per million average is a 

hugely important component of the proposed rule. We agree. We know that sulfur inhibits the 

catalytic converter’s ability to reduce emissions. Lower sulfur fuels at the pump mean fewer 

exhaust emissions in the air. It’s that simple. 

Further, sulfur reductions in the market fuels produce day one benefits. So while it will take a 

couple of decades for the current fleet to be replaced by Tier 3 compliant vehicles, reducing 

sulfur at the pump immediately will reduce emissions from every gasoline powered vehicle on 

our road, no matter how old. 

Gasoline sulfur reduction is also a critical element needed to enable benefits of future alternative 

vehicle technologies, for example, Direct Injection Lean Burn engines which have greater energy 

efficiency, as well as HCCI (homogenous charge compression ignition), pHCCI (premixed 

HCCI), RCCI (reactivity controlled compression ignition), and lean cruise/idle technology. 

Without this change, fuels and vehicles CANNOT operate as an integrated system and 

synergistically achieve emissions and energy efficiency goals. It is appropriate for regulators to 

put some burden on fuel suppliers to do their part to invest and reduce sulfur to optimize the 

emissions reductions of the system. The projected cost of the Tier 3 system is far higher for 

automakers than for the refinery industry (See April 24, 2013 Alliance Tier 3 Testimony, and 

EPA RIA at ES-8 ff.) 

But these standards cannot be met with vehicle changes alone, and the Tier 3 proposal recognizes 

another critical component in reducing vehicle emissions, and that is fuel quality, or, more 

specifically, the sulfur content in gasoline. We believe the proposed fuel standards for a 

nationwide supply of clean, ultra-low sulfur gasoline is critical for auto makers to meet the new 

and highly stringent vehicle emission standards.

33 - 78 Fed. Reg. 29908 at 29816 (May 21, 2013).

34 - As noted in Alliance testimony for this rulemaking, according to EPA, automakers will spend about 

$15 billion in just ten years to meet the requirements of this proposed rule, and effectively remove tailpipe 

emissions from the environmental equation. As EPA further states, combined with the fuel economy and 

greenhouse gas program, this rule would bring auto investment in the vehicle emission reduction 

programs through 2025 to more than $216 billion –about 100 times the investment that the oil industry is 

being asked to make under the NPRM.

47 - 78 Fed. Reg. 29908, 29858 (May 21, 2013).

Commenter: American Honda Motor Co., Inc.

As the agency is aware, through the use of sophisticated emissions control technology, the 

automotive industry has been able to achieve extraordinarily low exhaust levels throughout a 

vehicle’s life. The anticipated Tier 3 standards – and the LEV III standards of California – will 

push those emissions to near-zero levels. But doing so requires the use of vehicle technology and 

fuels that complement one another. Sulfur in gasoline has long been known to adversely affect 

catalyst performance and, as a result, achieving the Tier 3 and LEV III stringencies is highly 

dependent on the vehicles’ use of low-sulfur fuel. 
Chapter 5: Tier 3 Fuel Sulfur Program

5-12

Lowering sulfur will enable new vehicles to better meet the cleaner proposed emissions 

standards for the duration of their useful life, improving air quality as those vehicles work their 

way into the vehicle population. It’s also worth mentioning that lowering the sulfur content of 

gasoline has another, less gradual benefit. As the agency notes in the proposed rule, cleaner fuel 

“facilitates immediate emissions reduction from all vehicles on the road at the time the sulfur 

controls are implemented.” Failing to bring cleaner fuel to market in a timely manner would miss 

a fundamental opportunity presented by this systemic approach to regulating both vehicles and 

fuels. 

Setting fuel sulfur levels comparable to those currently set in California would ensure that the 

Tier 3, LEV III, fuel economy, and vehicle greenhouse gas policies are working not at odds with 

one another, but rather in a complementary manner, opening doors to future designs that are both 

cleaner and more efficient. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

Further reducing sulfur is not necessary for meeting new stringent vehicle emission standards, 

and auto makers are unlikely to introduce the vehicle emission technologies that are enabled by 

the lower sulfur fuel. And I’m talking about lean burn GDI.

Auto makers insist they need 10 ppm gasoline to enable lean burn GDI engines, and yet in 

Europe and Japan where 10 ppm fuel is available, lean burn GDI engine penetration peaked at 

about two percent and then tailed off. Research shows it maxing out at about three percent of the 

U.S. fleet. Diesel sulfur was kept at 15 ppm to enable an emissions control technology that never 

took off in the marketplace. Don’t make the same mistake with gasoline. Auto makers can meet 

the emission standards without further reductions to gasoline sulfur.

Commenter: Appalachian Mountain Club (AMC)

The adjustment in sulfur fuel content is needed as sulfur fouls the efficiency of vehicle catalytic 

converters, a key system component that reduces smog forming emissions and toxic air 

pollution. 

As stated above, AMC is very supportive of the provision that will reduce the sulfur content of 

gasoline from 30 parts per million (ppm) to 10 ppm . This will result in immediate emission 

reductions when implemented in 2017. 

Commenter: BMW of North America, LLC

To assist automakers in their efforts to comply with these stringent Tier 3 emission standards as 

well as with the upcoming MY 2017-2025 GHG/CAFE requirements, BMW strongly supports 

EPA’s proposal that Federal gasoline, including any ethanol-gasoline blend, contain no more 

than 10 parts per million (ppm) of sulfur on an annual average basis by January 1, 

2017. Uniformly low gasoline sulfur levels throughout the U S marketplace will enable 
Tier 3 Summary and Analysis of Comments

5-13

automakers to effectively optimize vehicle emission control technology to meet these rigorous 

standards in the required timeframe. 

Commenter: Chrysler Group LLC

Sulfur is the single most important gasoline parameter to enable manufacturers to broadly 

introduce gasoline direct injection (“GDI”) technologies to meet EPA’s air quality and 

greenhouse gas (GHG) requirements. The cause and effects are well known: Sulfur inhibits 

exhaust after-treatment conversion efficiency, so lower sulfur means lower emissions. 

In fact, EPA considered these very issues in the heavy-duty diesel context, so the discussion has 

already taken place. Specifically, in the 2007 Heavy-Duty Highway Rule, EPA recognized the 

necessity of adopting low sulfur diesel fuel to support diesel direct injection technology with 

advanced exhaust aftertreatment systems, the very same technology (but as applied to gasoline 

engines) that EPA seeks to foster in the current proposed rule, which, again, necessitates the 

adoption of low sulfur gasoline. 

Additionally, EPA’s creation of new fuel economy and GHG standards anticipated the 

nationwide availability of low sulfur gasoline. Consistent with that basis, Chrysler supported the 

concept of One National Program to improve fuel economy and reduce GHG emissions with the 

understanding that low sulfur gasoline would be called for in this next round of establishing 

tailpipe emissions standards, and which would ensure availability to enable advanced lean-burn 

GDI technologies. 

Advanced lean-burn GDI systems are an enabling technology to meet EPA and the National 

Highway Traffic Safety Administration’s (NHTSA’s) 2025 model year (MY) GHG and fuel 

economy requirements. As such, low sulfur gasoline, at 10-ppm or lower, is a prerequisite for 

lean-burn GDI systems achieving EPA/NHTSA’s GHG and fuel economy benefits. Conversely, 

without low sulfur gasoline, lean-burn GDI systems incur a significant fuel economy (and 

corresponding GHG) penalty due to more frequent sulfur regeneration events. 

The auto industry has already invested hundreds of millions of dollars to design, develop, tool 

and in some cases manufacture and produce lean-burn GDI systems. Without absolute assurance 

of low sulfur gasoline in the marketplace, the performance and GHG benefits of this promising 

technology will be significantly compromised.

As in previous rulemakings, Tier 3 continues to treat vehicles and fuels as a system, recognizing 

that fuels are critically important to achieve the full potential of advanced emission control 

technologies, especially during these historic time when regulations are driving near zero 

emissions and doubling fuel economy. Sulfur is the single most important gasoline parameter to 

enable vehicle technologies to meet these new requirements. The cause and effects are well 

known. Sulfur inhibits exhaust after treatment conversion efficiency, so lower sulfur means 

lower emissions.

Commenter: Clean Air Council
Chapter 5: Tier 3 Fuel Sulfur Program

5-14

The Alliance of Automobile Manufacturers, which includes BMW Group, Ford Motor Company, 

and others, has publicly stated that it supports ‘the lowest possible sulfur content at retail for 

uniformity at the pump for planning future technologies, and also to get the immediate benefit of 

existing vehicles as well as future ones, reducing sulfur poisoning of the catalyst and, therefore, 

minimizing exhaust emissions of the vehicle.’

Commenter: Delaware Department of Natural Resources (DNRC)

Sulfur in fuel inhibits the performance of catalysts that control vehicle exhaust, resulting in 

increased vehicle emissions. Reducing sulfur in fuel will reduce mobile source emissions of 

nitrogen oxides, carbon monoxide, fine particulate matter, and volatile organic compounds and 

continue the effective, proven approach of treating vehicles and fuels as an integrated system. 

Importantly, these reductions will begin immediately with the existing fleet so long as the 

vehicles are equipped with a functioning catalytic converter. Lower sulfur gasoline will also 

facilitate the deployment of advanced technologies that will improve fuel economy, reduce 

gasoline consumption and save consumers money. The effectiveness of EPA’s proposed Tier 3 

standards will continue to grow over the years as newer vehicles replace older ones. 

Commenter: Emissions Control Technology Association (ECTA)

The EPA neglects other benefits from low-sulfur gasoline. To meet the 2025 GHG regulations, 

automakers will leverage all their engine tools. Lean-burn direct-injection gasoline (lean GDI) is 

one not mentioned by the EPA. In the 2020-25 timeframe, CO2 reductions will cost about $50-

75 per percent (Corning Review, SAE 2013-01-0538). Lean-burn GDI (gasoline, direct injection) 

engines will deliver >10% CO2 reductions (Daimler SAE 2013-01-1299; Mercedes Kemmler 

Vienna Motorsymposium 2013) versus stoichiometric GDI engines, and it is our estimate that 

incremental costs will be less than $500. Most of the engine costs are in calibration, and the 

incremental exhaust costs reside in replacing a TWC with two LNT (lean NOx traps). This 

technology is not being considered for the United States due to high-sulfur gasoline (Mercedes, 

Kemmler, Vienna Motorsymposium, 2013).

Commenter: Environmental Defense Fund (EDF)

Cleaner fuel will also enable the technologies needed to meet the Tier 3 exhaust standards and 

enable the vehicles to meet the standards in-use for the duration of their useful life. Finally, 

lower sulfur gasoline facilitates the development of lower cost technologies to improve fuel 

economy. 

The preamble to the proposal and the RIA clearly outline the technical need for additional sulfur 

requirements. As EPA states in the preamble, “[R]obust data from many sources shows that 

gasoline sulfur at current levels (i.e., around 30 ppm on average) continues to degrade vehicle 

catalytic converter performance during normal operation. The most significant problem is for 

NOx. Today’s proposed NMOG+NOx vehicle emission standards, an 80 percent reduction from 

current Tier 2 standards, would not be possible without the gasoline sulfur controls we are 

proposing today.” This determination has been echoed by the Manufacturers of Emission 
Tier 3 Summary and Analysis of Comments

5-15

Controls Association in their recent report describing the adverse impact of fuel sulfur on 

emission control technology (97). 

In addition to protecting catalysts on existing vehicles and Tier 3 vehicles, automakers and 

emissions control manufacturers support cleaner fuel because it will allow for additional costeffective technologies to meet the later-year fuel economy and GHG standards. For example, the 

lean burn gasoline direct inject (GDI) engine, which offers a 5-15 percent fuel economy 

advantage over the stoichiometric GDI, is currently being used in Europe where 10 ppm fuel is 

available. The advanced NOx catalysts needed to maintain low NOx emissions in a lean GDI 

engine are especially sensitive to sulfur. The lean burn GDI could be deployed by automakers to 

meet the 2025 fuel economy and GHG emissions standards in the US if the 10 ppm fuel standard 

is finalized. Indeed, many manufacturers in the U.S. are developing the lean GDI technology in 

anticipation of Tier 3 fuel standards (98). 

97 - MECA, The Impact of Gasoline Fuel Sulfur on Catalytic Emission Control Systems (June 2013).

98 - Id.;.MECA, LEV III and Tier 3 Exhaust Emission Control Technologies for Light-duty Gasoline 

Vehicles (Apr. 2013).

Commenter: Ford Motor Company (Ford)

Sulfur, which occurs naturally in crude oil, is known for its notorious ability to poison catalysts 

and dramatically reduce the functionality of advanced emissions systems. Laboratory research 

has also shown sulfur to increase light-off temperature and decrease conversion efficiency, in 

addition to slowing the rich to lean air/fuel (A/F) transition. Sulfur in gasoline is also known to 

cause corrosion of metallic components of the engine and fuels system. A reduction in market 

gasoline sulfur levels can immediately reduce the emissions from all vehicles on the road. 

Improved fuel economy and reduced CO2 emissions are made possible in vehicles through 

engine operation at lean air-fuel ratios. While lean A/F ratios result in decreased hydrocarbon 

(HC) and carbon monoxide (CO) emissions, they increase oxides of nitrogen (NOx) emissions as 

three-way catalysts (TWC) have their highest efficiency for NOx reduction during stoichiometric 

or fuel rich conditions. Catalysts undergo sulfur poisoning when the sulfates formed during 

combustion (from the sulfur in the fuel) compete with NOx for the catalytic active sites on the 

TWC; this in turn reduces the lean NOx trapping functionality of the catalyst. Laboratory tests 

have shown a greater than 40% reduction in NOx emissions when decreasing sulfur from 30 ppm 

to 5 ppm.(5) 

In order to meet the increased CAFE requirements of tomorrow, manufacturers are developing 

lean-burn engines that will reduce fuel consumption, but this requires sophisticated sulfursensitive NOx control technologies. Thus, the lowering of market sulfur levels in fuels to 10 ppm 

maximum has been proposed in countries with advanced fuel economy and emissions 

requirements that utilize such technologies.

In addition to worldwide efforts in mobile source emissions reductions, ambient air quality 

continues to be a global issue of interest. Air quality improvement efforts are often made 

possible through maintaining ozone and smog levels to acceptable ranges. Smog consists of fine 
Chapter 5: Tier 3 Fuel Sulfur Program

5-16

particulate matter such as sulfate and nitrate aerosols. As stated above, fuel sulfur has a 

significant impact on NOx emissions that contribute to the formation of such aerosols, which 

furthers the importance for lowering fuel sulfur levels. Sulfur in the fuel has also been linked to 

the formation of sulfates in the exhaust stream. The lowering of sulfur levels in gasoline (and 

also diesel fuel) has been linked to lower smog-forming particulate matter emissions and 

improved air quality.

Recommendation: As communicated at the EPA and NHTSA public hearing on April 29, 2013 

on the Tier 3 NPRM, Ford strongly supports a reduction of sulfur levels to 10 ppm maximum for 

market fuels in order to meet the strict emissions standards and maintain the integrity of the 

engine and emissions system throughout the vehicle’s useful life and fully supports the detailed 

Alliance comments on sulfur.

5 SAE 2011-01-0300, D. Ball, et al., Effects of Fuel Sulfur on FTP NOx Emissions from a PZEV 4 Cylinder 

Applications. 

Commenter: General Motors LLC (GM)

There are a number of issues related to the market gasoline which are appropriately within the 

scope of the Tier 3 final rule, or a supplemental Tier 3 rulemaking. Such issues are integral to 

product design, planning and implementation for all OEMs because vehicles and fuels are a 

system and clean, efficient operation of vehicles is limited by the fuels on which they depend. 

EPA itself echoed this concept in the NPRM Preamble noting that its proposal promotes a 

“systems approach to addressing the impacts of motor vehicles and fuels on air quality and 

public health.” 

While OEMs discussed the interconnection of fuels and vehicle issues with EPA during the 

negotiations leading to the MY 2017-2025 GHG/FE requirements, EPA declined to include fuel 

issues in that rulemaking. However, at that time EPA gave the industry assurance that these 

issues would be addressed promptly within the Tier 3 rulemaking in order to facilitate the needed 

product changes to support the GHG/FE standards, as well as Tier 3 requirements. OEMs are 

spending billions of dollars on compliance with the GHG/FE rules and require the cleanest fuels 

possible to meet these obligations. (13) We urge EPA to support the progress toward cleaner 

vehicles by ensuring that the proper fuels are widely available. 

GM supports EPA in its efforts to reduce the sulfur content of fuel, and the 10 ppm annual 

average in the proposed rule is a step in the right direction.

Another key aspect of the proposal is the cleaner fuels that are included. Auto makers will need 

these cleaner fuels to meet the stringent Tier 3 emission standards EPA and California envision.

We must have clean fuels because the vehicles and fuel function as a single system in 

determining the emission performance of the vehicle. 

As EPA moves ahead to finalize the Tier 3 requirements, GM believes the provision for low 

sulfur fuel levels and other clean fuel properties is essential, as is outlined in the Alliance’s 

comments. And while clean fuels are needed to meet the Tier 3 standards on new vehicles, they 

also provide the added benefit of reducing emissions immediately across the entire on road fleet.
Tier 3 Summary and Analysis of Comments

5-17

13 According to EPA, automakers will spend about $15 billion in just ten years to meet the requirements 

of this proposed rule, and effectively remove tailpipe emissions from the environmental equation. As EPA 

further states, combined with the fuel economy and greenhouse gas program, this rule would bring auto 

investment in the vehicle emission reduction programs through 2025 to more than $216 billion –about 

100 times the investment that the oil industry is being asked to make under the NPRM. 

Commenter: Private Citizen

Vehicles and fuels are a system. Setting a strict gasoline sulfur standard of 10 ppm will cleanup 

every car on the road and enable the next generation of cleaner vehicle technologies. The result 

would be like taking 33 million cars off the road, and these benefits can be achieved for a penny 

or less per gallon of gasoline. 

Commenter: Hyundai Motor Group

The Hyundai Motor Group supports EPA’s proposal to lower the annual average sulfur retail

gasoline levels to 10 ppm. We believe a systems approach is necessary to reduce emissions to 

the stringent levels called for in the proposal. There is a large body of evidence that shows that 

with reduced sulfur levels, we will see an immediate benefit from all vehicles in the existing 

fleet, not just on vehicles with the latest technology.

Sulfur inhibits the ability of after-treatment technology to reduce emission levels of NOx, VOCs, 

PM, carbon monoxide, and air toxics, by depositing on the precious metal catalysts.

As we work to meet all of the low emission levels proposed in the Tier 3 rule, particularly the 

ppm standards. We need the catalyst to be working as efficiently as possible to meet both 

certification and in use requirements. Also as sulfur degrades the catalyst, it reduces useful life.

Auto makers are required to meet useful life standards of 150,000 miles for emission-related 

equipment as part of this regulation, so it is important that the technology works as intended.

Additionally, as auto makers introduced lean burn technologies that we see as necessary to meet 

stringent future GHG regulations, low sulfur levels must be implemented to minimize 

detrimental impact to NOx after treatment.

Commenter: Johnson Matthey

One of the important aspects of the Tier 3 proposal is to reduce the sulfur level in the 

gasoline fuel. Sulfur compounds cannot be transformed into something harmless in the way that 

a NOx molecule is, turning to NOx catalysts. Therefore, all sulfur emissions from the engine are 

bad for the environment, and the only way they can be prevented from entering the environment 

is by removal from the fuel itself.

The catalyst technology Tier 3 proposal is across the whole vehicle fleet. That’s gasoline and 

diesel vehicles. It exists today, and it’s already in the marketplace. New generations of catalysts 

are continually being developed, and they have further enhancements and performances.

Implementation of these catalyst technologies to meet Tier 3 proposals is what our industry 
Chapter 5: Tier 3 Fuel Sulfur Program

5-18

thrives on. We have a long track record of achieving these tighter emissions limits successfully, 

and this proposal would be no different.

Sulfur also poisons the efficiency of the catalyst for criteria emission control. To ensure that the 

full range of light duty vehicles comply with Tier 3 proposals, both at time of certification and 

during their use in the real world, the proposed lower gasoline sulfur levels, 10 ppm average, are 

needed. The EPA has recently completed an excellent and extensive evaluation of sulfur effects 

on the current Tier 2 vehicle fleet that clearly shows significant emission benefits from reducing 

gasoline sulfur levels on those existing vehicles.

And as we move to the future, vehicle manufacturers are working hard to meet greenhouse gas 

requirements. Exhaust temperatures are expected to get cooler, exacerbating these sulfur 

poisoning effects on the catalyst. This remaining clean fuel is increasingly important as we 

move forward.

Having low sulfur fuel may also enable new technologies to be introduced, such as NOx 

absorber catalysts, which are leading catalyst technology for highly fuel efficient clean burning 

gasoline engines, and need these ultra-low sulfur fuel levels to function at peak effectiveness, 

and allow these engines to meet their fuel economy potential. Sulfur in diesel fuel is already 

limited to a maximum of 10 ppm for these reasons, and sulfur and gasoline should also be 

limited to the proposed 10 ppm average.

Commenter: ECTA

To be sure, we have cars today that are meeting the Tier 3 average fleet requirements with 30 

ppm sulfur fuel. However, all these cars are small and compact. It is a very different story in 

trying to get a large vehicle to Tier 3 average emission levels. Not only are the catalysts 

compromised, but the sensors are affected, causing complexities in on board diagnostics, which 

are so critical to proper fleet emissions monitoring. We demand 150,000 durability in our cars.

High sulfur fuel makes this very difficult.

We also have catalyst formulations that are not as sensitive to sulfur as others. This is partly the 

result of unique formulations derived from -- through catalyst R&D. These formulations are 

usually intellectual property of the developers. They do not have 100 percent of the market 

share.

Further, for many reasons, the catalyst might be designed differently to meet the the market or 

technical requirements, or be placed in different conditions. We all drive different vehicles with 

different engines and different designs. The field is very complex. This is why we need the low 

sulfur fuel because the technologies and engines are becoming so complex.

I just attended the SAE International Annual Congress in Detroit. Fantastic. Developments are 

coming very quickly, but -- very important -- most researchers are using clean fuels in their 

development of engines and catalysts. We will see commercialized gasoline engines by 2020 

that consume 20 to 30 percent less fuel. These new engines are complex, and many are lean, like 

diesel. Lean NOx mitigation for gasoline requires less than 10 ppm sulfur fuel. It doesn’t make 
Tier 3 Summary and Analysis of Comments

5-19

sense to tie one arm behind the back of the auto engineers by requiring them to use relatively 

dirty fuel.

Commenter: Manufacturers of Emission Controls Association (MECA)

A critically important element to ensuring that future gasoline vehicles will be able to comply 

with EPA’s proposed Tier 3 emission limits is EPA’s proposed reduction of gasoline fuel sulfur 

levels to a 10 ppm national average starting in 2017. 

MECA has consistently supported the introduction of the lowest possible fuel sulfur limits used 

with mobile sources to enable the use of best available exhaust emission controls and minimize 

the impacts of fuel sulfur on catalyst performance and durability. 

Commenter: Mercedes-Benz USA, LLC on behalf of Daimler AG

The impact of a 10 ppm retail average sulfur limit in the Tier 3 proposal is immediate and 

enduring for both new vehicles as well as legacy fleets.

Mercedes-Benz strongly supports the 10 ppm annual average for gasoline in the Tier 3 proposal 

and requests that this element be incorporated in the final EPA Tier 3 rulemaking. This 

advancement in fuel quality will immediately benefit the existing vehicles on the road by 

improving the function of exhaust aftertreatment components and by decreasing the formation of 

smog-producing pollutants.

In 2006, Mercedes-Benz first capitalized on the value of low sulfur gasoline and the reduction to 

fuel consumption it enables when it introduced in the EU the 350CGI CLS luxury sedan, which 

is equipped with stratified lean burn combustion. Depending on the driving mode, engine speed, 

and load, gains in the fuel efficiency can range between five and 15 percent as compared to 

conventional stoichiometric combustion. Incorporation of this technology in the EU is enabled 

by a 10 ppm refinery limit in comparison to the 10 ppm annual average as proposed in the Tier 3 

rulemaking.

But sulfur reduction is not a lean burn discussion. Even existing power train architectures, 

including downsized turbocharged gasoline direct injected engines would also benefit from 

reduced sulfur and fuel, so no longer would a portion of the fuel savings realized need to be 

expended by periodically burning off sulfur to maintain optimum effectiveness in exhaust after 

treatment systems.

Additionally, prior testimony highlights the fact that power train technologies which increase 

efficiency result in core exhaust gas temperatures, which promote sulfur deposition and inhibit 

burn off. Thus, the effect of low sulfur on the current fleet is immediate and enduring. No other 

single step can provide retroactive and future benefits in criteria emissions and greenhouse gas 

reduction.

Commenter: Motor & Equipment Manufacturers Association (MEMA)
Chapter 5: Tier 3 Fuel Sulfur Program

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The steady phase-in of lower sulfur fuel will provide greater opportunities for deploying new 

technologies, such as lean-burn engines, and for improving emissions and fuel economy 

performance. 

Commenter: National Automobile Dealers Association (NADA)

Vehicle emissions control is a direct function of the interaction of motor vehicle components and 

systems and motor vehicle fuels. The time-honored tug-of-war between ‘auto’ and ‘oil’ is a 

function of the basic laws of chemistry and physics. To the extent fuels can be controlled to 

make them cleaner or easier to clean, less need be done by vehicle components and systems. The 

reverse is also true. 

Commenter: New York State Department of Environmental Conservation

Maximizing the benefit to the environment from this investment in catalytic exhaust 

aftertreatment requires appropriate reductions in fuel sulfur content. The Department urges EPA 

to implement the annual average gasoline sulfur standard as proposed, with most gasoline being 

subject to a 10 ppm sulfur standard in 2017. 

However, the proposed gasoline sulfur standard is a significant component of the emission 

control system. The reduction is gasoline sulfur provides substantial benefits, particularly in the 

early years of the program, due to emission reductions from the existing vehicle fleet. Lower 

gasoline sulfur content will also minimize the in-use emissions of Tier 3 and LEV III vehicles 

throughout their lives.

The engine exhaust after treatment fuel needs to be treated as a system, as EPA has recognized 

and done with the Tier 3 and now the Tier 3 standards and heavy duty standards as well. And we 

fully support the proposal here to regulate the system again. Reduction in the sulfur content of 

gasoline facilitates improvements in engine and exhaust after treatment signs that can further 

reduce emissions of ozone precursors, as well as reductions in greenhouse gas emissions 

improvements in fuel economy as other technology is enabled.

Sulfur is well-known poison catalysts that are vital for meeting existing and proposed standards.

There’s been concern expressed about this for many years now, and Tier 3 made a lot of progress 

in reducing standards that – sulfur standards, and now it’s time to go the next step and bring it 

down even further.

Commenter: Pennsylvania Department of Environmental Protection (DEP)

EPA’s proposal would establish more stringent vehicle emissions standards and reduce the sulfur 

content of gasoline beginning in 2017. According to EPA, the proposed gasoline sulfur standard 

of 10 parts per million (ppm) average, down from the current 30 ppm average, would make 

vehicle emission control systems more effective for both existing and new vehicles, and would 

enable more stringent vehicle emissions standards. 
Tier 3 Summary and Analysis of Comments

5-21

DEP realizes the potential for significant emission reductions from the proposal as soon as the 

Tier 3 gasoline standards take effect. A 10 ppm average sulfur level in gasoline would allow 

Tier 3 vehicles’ three-way catalysts to perform at an optimum level and potentially allow the use 

of more cost-effective emission controls on vehicles. In addition, a 10 ppm average sulfur level 

in gasoline will immediately lower emissions from vehicles that comply with Tier 2 standards. 

These reductions would occur because the lower sulfur levels in Tier 3 gasoline will reduce 

sulfur ‘blinding’ of the catalysts that has occurred from the use of current gasolines. Catalyst 

‘blinding’ inhibits the performance of the catalysts and consequently Tier 3 gasoline will provide 

for almost immediate additional NOx emissions reductions from the existing fleet. 

Commenter: Union of Concerned Scientists (UCS)

One of the unique benefits of Tier 3 is that, by lowering sulfur in the gasoline that goes into 

vehicles already on the road, the program will have an immediate positive impact. Reducing the 

sulfur content of gasoline helps existing catalytic converters work more efficiently, reducing the 

emissions from the legacy fleet even while we wait for the vehicle fleet to turn over. By setting 

standards for the fuel and the vehicle together (what is referred to as the “system based 

approach”), the Tier 3 standards are able to achieve the greatest emission reductions at the lowest 

cost to society.

Commenter: Utah Air Quality Board

The Board recognizes that the proposed Tier 3 Program addresses the vehicle and its fuel as an 

integrated system. The proposed low-sulfur gasoline component (Tier 3 Gasoline) — which 

would reduce sulfur content to an average of 10 ppm – is required to enable the advanced 

emissions reduction technologies that will be installed on new vehicles by automobile 

manufacturers beginning in 2017. In addition to enabling these advanced pollution cutting 

technologies, the Board recognizes that the Tier 3 Gasoline with 10 ppm sulfur content will also 

yield immediate and significant emissions reductions in our existing fleet of vehicles beginning 

on the day the fuel becomes available at the pump. We support the penetration of Tier 3 Gasoline 

into the market in Utah as soon as possible. 

Commenter: Sierra Club Southeastern Pennsylvania Group

According to the Delaware Valley Regional Planning Agency, the area MPO, conformity with 

the State implementation plan is only being achieved through the continuing improvements in 

vehicle-related pollution controls. Now we can assist the manufacturers of the nation’s vehicles 

and advance clean air efforts by adopting these standards and clean up fuel at the refinery.

Commenter: State of Utah

The proposed Tier 3 Program addresses the vehicle and its fuel as an integrated system. The 

proposed Tier 3 gasoline—with a reduced average sulfur content of 10 ppm—would enable the 

advanced catalytic converters to function more effectively. Therefore, Tier 3 gasoline should be 

made available at the pump as soon as possible. 
Chapter 5: Tier 3 Fuel Sulfur Program

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Commenter: United Automobile Workers

A national standard for ultra-low sulfur gasoline is an especially cost-effective way to achieve 

substantial emission-reductions from vehicles. Low-sulfur gasoline allows a vehicle’s catalytic 

converter to operate at higher efficiency, in turn leading to lower tailpipe emissions and 

decreasing the formation of smog-producing pollutants from cars and trucks. Looking forward, a 

reduction in sulfur will also enable the introduction of new fuel-saving technologies in the next 

generation of vehicles. Since manufacturers know that all vehicles will be using the same 

standardized low-sulfur gasoline across the country, they can include technologies in new 

vehicles that will capitalize on this fuel development. 

Our Response:

As explained in Sections II and V.M of the preamble to the final Tier 3 rule, we are 

lowering the existing gasoline sulfur standards under section 211(c)(1), because emission products of 

gasoline with current levels of sulfur cause or contribute to air pollution which may reasonably be 

anticipated to endanger public health or welfare, and because emission products of gasoline with 

current levels of sulfur will impair to a significant degree the emissions control device or systems on 

the vehicles subject to the final Tier 3 standards. As discussed in Section II.B of the preamble to the 

final rule, control of gasoline sulfur to 10 ppm will lead to significant reductions in emissions of 

these pollutants, with the benefits to public health and welfare significantly outweighing the

costs. As also discussed in Chapter 4 of this Summary and Analysis of Comments document 

(and further in Section IV.A.6 of the preamble to the final rule and Chapters 4 and 5 of the RIA), 

a reduction in gasoline sulfur from the Tier 2 30 ppm average to the Tier 3 level of a 10 ppm 

average is necessary to enable the new vehicle fleet to meet the Tier 3 standards, as well as 

achieve immediate emission reductions from the existing fleet. Lower sulfur gasoline will 

enable the needed reductions in vehicle emissions and the 10 ppm average sulfur standard is a 

feasible standard for refiners to meet taking into consideration costs and other factors. Further, 

the 10 ppm average sulfur standard will also help prevent the significant impairment of the 

emission control systems expected to be used in Tier 3 technology, significantly improve the 

efficiency of emissions control systems currently in use, and continue prevention of the 

substantial adverse effects of sulfur levels on the performance of vehicle emissions control 

systems.

As discussed in Chapter 5.1.1.2 of this Summary and Analysis of Comments document 

(and in Sections III.A and III.B of the preamble to the final rule), a 10 ppm annual average 

standard will help reduce current levels of sulfur that contribute to ambient levels of air pollution 

that endanger public health and welfare. Lowering gasoline sulfur will not only provide 

emissions benefits when combined with Tier 3 vehicle technologies, but it will also help to 

reduce emissions of pollutants from vehicles currently on the road today. As also discussed in 

Section IV.A of the preamble to the final rule, we have tested a wide range of vehicles to better 

understand the impact that even lower gasoline sulfur could have on emissions. Our test data 

showed significant NOX and VOC reductions when vehicles were tested on low sulfur gasoline. 

Further, Section III.B of the preamble, shows that lowering average gasoline sulfur from 30 to 10 

ppm will result in approximately 260,000 less tons of NOX and 50,000 less tons of VOC almost 

immediately when the Tier 3 gasoline sulfur standards take effect.
Tier 3 Summary and Analysis of Comments

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Comments on GHG, CAFE, and CO2 emissions are beyond of the scope of the Tier 3 

rulemaking.

5.1.1.4. Impacts on Cost, Supply, and RFS Program

What Commenters Said:

Commenter: American Fuel & Petrochemical Manufacturers (AFPM)

EPA proposes that refiners further lower the amount of sulfur from gasoline despite the fact that 

our industry already removed 90 percent since 2004. The remaining incremental reduction of 

trace amounts of sulfur will cost refiners almost as much as the Tier 2 reduction 10 years ago, 

which removed 15 times more sulfur than the proposed Tier 3 regulation would require.

Commenter: Medical Advocates for Healthy Air

Other arguments mention the need for heavy investment in the newer technologies to achieve the 

standards of Tier 3. Yet oil refineries supplying gasoline to California are already reducing the 

sulfur content to 10 ppm. The technology already exists, is working, and can be installed at the 

national level with minimal increase—if any—to the cost of gasoline. As mentioned above, the 

new standards will increase employment and contribute positively to the nation’s GDP. 

Commenter: Small Business Refiners (SBR)

EPA Enforcement continues to pursue its National Petroleum Refinery Initiative that focuses on 

NSR/PSD, NSPS, LDAR, and benzene. The refining industry has spent over $6 billion to install 

additional control technologies, $80 million in civil penalties, and $75 million in supplemental 

environmental projects. Through investments, the refining industry has reduced sulfur emissions 

in gasoline from 300 ppm to less than 30 ppm and sulfur emissions in diesel from 500 ppm to 

less than 15 ppm. Tier 3 Fuels reduction in gasoline sulfur will be significantly more expensive 

per pound of sulfur removal, than previous regulations. Tier 2 sulfur reduction cost[s] 

approximately $100,000 per ppm of sulfur, where Tier 3 fuels is expected to cost $900,000 to 

$1,000,000 per ppm of sulfur reduction. 

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

Instead, the Proposed Rule may hasten the impending blend wall under the Renewable Fuel 

Standard (‘RFS’) by exacerbating the increase in exports to foreign markets and decrease in 

supply to the U.S. markets brought on by the RFS and lack of consumer demand. 

Our Response:
Chapter 5: Tier 3 Fuel Sulfur Program

5-24

As discussed in Chapter 7.2 of this Summary and Analysis of Comments document (and 

in Section VII.B of the preamble to the final rule), our cost analysis shows that refiners will 

make about $2.025 billion in capital investments to achieve sulfur reductions to meet the Tier 3 

gasoline standards. These capital investments are expected to be made over the 6 years that the 

Tier 3 program is expected to be phased in, which would spread out the capital costs to average 

about $330 million per year. When fully phased-in, we estimate that the national average 

refinery cost of compliance with the Tier 3 sulfur control program, with a nationwide credit 

trading program, will be 0.65 cents per gallon averaged over all gasoline.

We disagree with the comment that the costs associated with complying with Tier 3 may 

indirectly “hasten the “impending blend wall” under the RFS program. As highlighted in the 

2014 RFS Annual Rule proposal (“2014 Standards for the Renewable Fuel Standard Program; 

Proposed Rule”, 78 FR 71732, November 29, 2013), the Agency believes that the E10 blendwall 

was reached in 2013. Therefore, the Tier 3 program can do nothing to hasten its arrival. Even if 

this were not the case, there would be virtually no impact. The commenter highlights the 

potential for the costs of complying with Tier 3 to increase exports as a reason why Tier 3 may 

hasten the arrival of the blend wall. However, even if Tier 3 were to encourage some US refiners 

to export more of their gasoline, the supply would then be made up with reductions in exports by 

other refiners or increases in imports from abroad. This volume would also be subject to the 

same RFS standards, resulting in no impact on the RFS program as a whole. To the extent that 

Tier 3 does increase overall compliance costs for gasoline, and prices to consumers rise along 

with it, this could have an impact on consumer demand for gasoline. Given the very small 

projected increase in cost for Tier 3 (0.65 cents/gallon on average) the impact on consumer 

demand would be very small. However, even then it would have no meaningful impact on the 

RFS program as a whole, since the RFS standards are percentage standards that are adjusted on 

an annual basis to reflect whatever happens to gasoline and diesel fuel demand for whatever 

reason. The impact of Tier 3 would be imperceptible in comparison to other changes in the 

marketplace (e.g., changes in crude oil prices).

While we recognize that there are other regulations that are imposing compliance costs 

on the refining industry, including other EPA regulations, these costs do not preclude 

implementation of the Tier 3 standards, and such comments are otherwise beyond the scope of 

this rulemaking.

5.1.1.5. Harmonization with California & Other Countries

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Ultra-low sulfur gasoline has been available in California for years, and the ability to comply 

with emissions standards in California is premised on the use of such fuel, recognizing the need 

to treat the vehicle and the fuel as a system.
Tier 3 Summary and Analysis of Comments

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One final point on sulfur. You’ve already heard it this morning, and that is that we have fallen 

behind other countries. The proposed rule would help Americans to get gasoline with sulfur 

limits approaching 10 parts per million cap, which is like the retail sulfur – the retail levels of 

sulfur already available in Europe and Asia.

Commenter: American Honda Motor Co., Inc.

California has recognized this in its LEV III standards, requiring an average of 15 parts per 

million, and a cap of 20 parts per million. It is critical that EPA set a national gasoline sulfur 

average and cap levels equivalent to those specified in California regulations.

Commenter: Boulder County Board of Commissioners and Boulder County Board of Health

These are cost-effective, proven technologies that are almost entirely the same as those already 

in place on California vehicles. Further, California’s gasoline already achieves 10-ppm sulfur on 

average, as do other nations, including the European Union, Japan, and – by 2017 – China.

Commenter: California Air Resources Board (CARB)

CARB staff strongly supports the proposed Tier 3 gasoline sulfur standards and applauds the 

efforts of U.S. EPA staff for bringing our fuel programs in alignment. 

U.S. EPA is proposing to lower the sulfur standard in gasoline and ethanol-gasoline blends to a 

10 parts per million (ppm) annual average. California’s gasoline already meets the proposed 10 

ppm sulfur standard. For many years California has led the nation in gasoline quality, including a 

low-sulfur standard. On December 31, 2003, California lowered the sulfur cap on gasoline from 

80 ppm to 60 ppm. Then on December 31, 2005, the sulfur cap was lowered from 60 ppm to 30 

ppm. And finally, on December 31, 2011, the sulfur cap was lowered to 20 ppm. The 20 ppm 

sulfur cap brought the in-use fuel’s sulfur average in California to about 9 ppm (2). 

(2) http://www.arb.ca.qov/reqact/2012/leviiiqhq2012/levisorpdf 

Commenter: Chrysler Group LLC

California recognizes the environmental benefits of low sulfur gasoline and requires 10 ppm 

sulfur in its LEV III regulation as an enabler to meet the Air Resources Board’s super ultra-low 

emission vehicle (SULEV) fleet average requirements. Requiring low sulfur gasoline in these 

Tier 3 rules will further harmonize Tier 3 and California LEV III to realize the emission benefits 

and to maximize new vehicle development and manufacturing efficiency. 

We will continue to work with EPA to bring California LEV III and Tier 3 as close as possible, 

with the goal of a completely harmonized California and Federal, one national criteria pollutant 

program. Low sulfur gasoline is a vitally important and critical element in achieving this goal.

Commenter: City of Philadelphia Department of Public Health Management Services (AMS)
Chapter 5: Tier 3 Fuel Sulfur Program

5-26

So in summary, I would like to have the rule be adopted as quickly as possible because the 

standards are consistent with California and other European countries already have.

Commenter: Delaware Department of Natural Resources (DNRC)

The Tier 3 standards support our efforts by reducing the average gasoline sulfur concentration 

from 30 ppm to 10 ppm, which is consistent with the international trend to reduce sulfur in 

gasoline. 

Commenter: Emissions Control Technology Association (ECTA)

From a general global perspective, Japan, Europe, and even China are moving to 10 ppm sulfur 

gasoline. By not doing this, the United States will be a significant major outlier and cause vehicle 

options and costs to be higher than in other major markets. 

Commenter: Environmental Defense Fund (EDF)

Reducing the sulfur content in gasoline from 30 parts per million (ppm) to 10 ppm will align the 

federal standard with those of California, the European Union, and Japan. Timely 

implementation of a national, unified sulfur standard will drive investment and development of 

emissions control technology, while allowing manufacturers to efficiently align technology 

upgrades with fuel efficiency and GHG emissions standards. 

Finalizing the tighter fuel standard would bring the U.S. in line with the cleaner fuel already 

required in California, Europe, and Japan. Canada is also proposing 10 ppm sulfur fuel. 

Commenter: Environmental Law and Policy Center (ELPC)

In reducing the sulfur content from 30 parts per million to 10 parts per million, that is a critical 

step to improving air quality. And we know that that standard is achievable because it is being 

met in California, Europe, and Japan.

Commenter: Ford Motor Company (Ford)

As mentioned earlier today, other markets with advanced emissions requirements, such as those 

found in Asia and Europe, are particularly concerned with high quality market fuels containing 

ultra-low sulfur fuels of 10 ppm to ensure catalysts maintain their high efficiencies throughout 

the expected useful life of the vehicle. Improved fuel economy and reduced CO2 emissions are 

made possible in vehicles through engine operations at lean air fuel rations, as Frank just 

mentioned. 

Additionally, the proposed rule enables Americans to enjoy immediate air quality benefits 

through operating on gasoline with sulfur limits approaching the 10 ppm cap similar to those 

already in place around the world.
Tier 3 Summary and Analysis of Comments

5-27

Commenter: Hyundai Motor Group

While we understand some refineries may face challenges in meeting the level proposed in this 

rule, we want to point out that by setting a 10 ppm average annual standard, EPA will be 

bringing the U.S. gasoline specifications in line with California, Japan, Korea, and the European 

Union.

In particular, South Korea has an average 10 ppm standard in place – has had an average 10 ppm 

standard in place since 2009. Also California has a cap of 20 ppm, and the average sulfur level 

in the fuel in the State is 10 ppm. Lastly, Japan and the EU have set a cap of 10 ppm, which is 

much more stringent than an average annual level proposed by EPA. All of these jurisdictions 

have recognized the importance of ensuring low sulfur levels in fuel. It is a reasonable and 

necessary standard for the U.S. as well.

Commenter: International Council on Clean Transportation (ICCT)

The ICCT also commends the EPA for proposing to reduce gasoline sulfur to 10 ppm. Japan and 

South Korea have required 10 ppm sulfur in gasoline since 2007 and Europe since 2009. Even 

Chile has required 15 ppm sulfur in gasoline since 2010. Given the leadership shown by the US 

in most environmental areas, it is important for the US to catch up on gasoline sulfur.

Commenter: ECTA

It’s essential the U.S. refinery industry enter the 21st century by providing an average of 10 ppm 

fuel. Europe and Japan have had it for years. China is doing so now, and will have it throughout 

the country in 2017. And India and Brazil are considering moving in this direction.

It would be shameful if the U.S. still had 30 ppm sulfur and these countries have clean fuel.

They all realize less than 10 ppm sulfur fuel is critical to clean vehicles. It all ties together.

Commenter: Manufacturers of Emission Controls Association (MECA)

Adoption of a 10 ppm average gasoline sulfur limit by EPA will bring the U.S. in line with other 

major vehicle markets in Europe, Japan, South Korea, and China where 10 ppm gasoline and 

diesel fuel sulfur caps are already in place or will be in place by 2018. 

Commenter: Union of Concerned Scientists (comment campaign)

I support Tier 3 standards that will keep the United States on pace with global trends to reduce 

the sulfur concentration of gasoline from 30 parts per million (ppm) to 10 ppm. 

Commenter: Michigan Department of Environmental Quality (MDEQ)

Once again, given California’s regulations, we know this concentration is achievable. 
Chapter 5: Tier 3 Fuel Sulfur Program

5-28

Commenter: National Association of Clean Air Agencies (NACAA)

Further, California’s gasoline already achieves 10-ppm sulfur on average. Finally, gasoline in 

other nations, including those in the European Union and Japan, is subject to a 10-ppm cap. 

China has also adopted requirements for 10-ppm sulfur, to take effect in 2017. 

Commenter: New York State Department of Environmental Conservation

The gasoline sulfur standards are clearly feasible. 

Many jurisdictions (European Union, Japan, South Korea, Beijing, China and California) are 

meeting comparable sulfur standards now. The processing technology necessary to produce 

gasoline meeting a 10 ppm sulfur standard is well established and commercially proven. 

Hydrodesulfurization has been used in oil refining since at least the early 1950s. Processes 

tailored to a wide variety of refinery streams, including those that contribute significant amounts 

of sulfur to the gasoline pool, have been developed and are in commercial use. 

We also fully support adoption of the proposed standards regulating the sulfur content of 

gasoline. When we adopted the California motor vehicle emissions standards in 1990, the Clean 

Air Act pretty much hinders New York and other States from adopting the California fuel 

standards. I won’t say it’s impossible, but it is a high hurdle.

The proposed gasoline sulfur limited of 10 parts per million is widely accepted, developed 

around the developed world. It’s currently the standard in the EU, Japan, South Korea, and in 

California, and China is even moving forward with the 10-part per million sulfur standard.

Commenter: Philadelphia Physicians for Social Responsibility

Now 13 years after the Tier 2 final rules on sulfur were published, it’s time to update these 

regulations. We know that we have the technical ability to do this because we already require 

these standards in California, Japan, South Korea, and most of Western Europe. Because you 

will hear from many others on the Tier 3 rules, I will limit my few minutes to the harmful effects 

of sulfur.

Commenter: Sierra Club

Refiners in other countries, such as Japan and 30 European nations, already are meeting a 10 

ppm gasoline sulfur cap standard. In addition, California refiners are already producing gasoline 

that averages 10 ppm sulfur content. Indeed, even without the proposed averaging, banking and 

trading (ABT) improvements, EPA demonstrates that a 10 ppm gasoline sulfur standard is 

feasible. 

Commenter: Southern California Association of Governments (SCAG)
Tier 3 Summary and Analysis of Comments

5-29

There appears to be some differences between the proposed Tier 3 standards and California’s 

LEV III Regulations and California gasoline sulfur content standards. While acknowledging the 

complexities and nuances of these programs, harmonization of the proposed Tier 3 with the 

California program is important from a business and manufacturer continuity perspective. We 

believe that such harmonization may yield savings to California residents through the 

efficiencies of scale in the production of vehicles that meet one national standard. 

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

Annual Average Sulfur Standard. The Proposed Rule would lower the annual average sulfur 

standard for gasoline refined, blended or imported from 30 ppm sulfur to 10 ppm sulfur on 

January 1, 2017. EPA states that Europe, Japan and other countries have moved to 10 ppm 

sulfur, so it is clear that U.S. refineries can also adapt. The make-up of refineries in the United 

States and Europe differs dramatically, with certain European markets having very little or no 

refining capacity and are thereby dependent on other markets for their refined products. These 

markets may have been able to purchase certain grades from refineries in other countries without 

the refineries having to undergo any dramatic changes to meet these markets’ needs. 

Furthermore, European markets use diesel fuel rather than gasoline for their transportation needs 

at a much higher rate than the United States. Simply because other countries have lowered their 

sulfur standard in gasoline does not necessarily mean that the U.S. refinery complex will be able 

to supply lower sulfur gasoline in the quantities required by the U.S. markets without 

considerable expense and cost to U.S. gasoline prices and the U.S. economy. 

Commenter: Union of Concerned Scientists (UCS)

Tier 3 is also consistent with the global trend to reduce sulfur in gasoline. Refiners are already 

producing ultra-low sulfur fuel in California and much of the developed world – demonstrating 

that the technology to meet these standards has already been deployed. In 2012, the Hart Energy 

International Fuel Quality Center ranked the top 100 countries based on sulfur limits in gasoline 

(12). The United States, at the current level of 30 ppm, is ranked 47th, with higher sulfur than 

Japan, South Korea, Turkey, Taiwan, Thailand, Chile and all of Europe.

12 - International Fuel Quality Center. 2013. International Gasoline Rankings – Top 100 Sulfur. Online at 

http://www.ifqc.org/NM_Top5.aspx accessed on July 1, 2013.

Commenter: United Automobile Workers

We applaud the EPA for taking the right approach, one that recognizes the connection between a 

vehicle’s emissions and its fuel, and treats them as a connected system. This approach will also 

create a nationwide harmonization of our fuel standards and will bring us in line with low-sulfur 

fuel requirements already available in California, Europe, and Japan. Our nation’s automakers 

will then be able to use a broader range of technologies to meet the significant environmental 

challenges facing our industry. 

Commenter: United Steelworkers Union (USW)
Chapter 5: Tier 3 Fuel Sulfur Program

5-30

Once the proposed regulations to lower overall sulfur emissions in gasoline to 10ppm are 

finalized, the European Union and China will either implement in tandem or have in place 

standards of ultra-low sulfur gasoline equivalent to the EPA Tier 3 Motor Vehicle Emission and 

Fuel Standards. By aligning emission standards with such large economic regions, U.S. refiners 

will be able to compete both domestically and globally in providing superior refined products to 

consumers. 

Commenter: State of Utah

Experience in other countries and in California demonstrates that the lower-sulfur Tier 3 gasoline 

will yield immediate and significant emissions reductions in our existing vehicle fleet. Therefore, 

Tier 3 gasoline should be made available at the pump as soon as possible. 

Our Response:

The commenters are correct that gasoline desulfurization technologies are well known, 

readily available, and have been further demonstrated by current fuel programs in California, 

Asia, and Europe. Under California’s Phase 3 Reformulated Gasoline program (CaRFG3) and 

the Predictive Model that California refiners use to demonstrate compliance, California gasoline 

currently contains approximately 10 ppm sulfur on average. Europe has a 10 ppm sulfur cap that 

has been adopted by the 30 Member States that comprise the European Union (EU) and the 

European Free Trade Association (EFTA) as well as Albania and Bosnia-Herzegovina. Japan 

also has a 10 ppm gasoline sulfur cap, and a 10 ppm sulfur limit for gasoline was recently 

introduced in Beijing, China. As these are all 10 ppm sulfur cap standards, they are considerably 

more stringent than the 10 ppm annual average standard being finalized today because each 

batch of gasoline produced at every refinery must meet the 10 ppm cap. Therefore, every 

refinery must be designed to meet this cap regardless of changes in crude oil supply, operation 

conditions, or product mix.

While we acknowledge that the fact that other countries have a similar sulfur standard is 

not a reason for the U.S. to adopt it, this is not the reason we are lowering the sulfur content. As 

discussed in Chapters 2 and 3 of the Summary and Analysis of Comments document, we are 

controlling sulfur because emission products of gasoline with current levels of sulfur cause or 

contribute to air pollution which may reasonably be anticipated to endanger public health or welfare, 

and because emission products of gasoline with current levels of sulfur will impair to a significant 

degree the emissions control device or systems on the vehicles subject to today’s final Tier 3 

standards.

In response to the comment that the gasoline desulfurization technologies are not 

appropriate for the U.S. gasoline market, we note that many of these technologies were 

demonstrated under the current Tier 2 program. However, we agree that many oil refineries 

outside of the United States operate differently from their U.S. counterparts. U.S. refiners have 

invested more heavily in fluidized catalytic cracker (FCC) units than the rest of the world to 

maximize gasoline production. Because the FCC unit is responsible for nearly all the sulfur that 

ends up in gasoline, U.S. refineries can face a bigger challenge in achieving 10 ppm gasoline 

sulfur levels, however that is changing. The 2013 Annual Energy Outlook produced by the 
Tier 3 Summary and Analysis of Comments

5-31

Energy Information Administration supports the view that the U.S. demand for diesel fuel is 

increasing while the demand for gasoline is decreasing, starting the process that will make the 

U.S. more like Europe. Thus, U.S. refiners seem to be beginning to move away from relying on 

the FCC unit as the most important refinery unit. Further, as discussed in more detail in Section 

V.L of the preamble to the final rule, the challenge of complying with more stringent gasoline 

sulfur control will decrease over time. The review of gasoline sulfur control in California and 

elsewhere, and the future trend for gasoline demand, show that achieving 10 ppm is feasible. 

The Tier 3 requirements are less demanding than those of Europe or Japan, for a number of 

reasons. First, the Tier 3 10 ppm standard is a refiner annual average standard, rather than sulfur 

cap. Second, the Tier 3 program has an 80 ppm refinery gate cap, which allows individual 

gasoline batches to vary in sulfur level (as long as they meet the 10 ppm annual average). Lastly, 

the Tier 3 ABT program allows refiners to generate credits for overcompliance with the standard 

and to bank or sell those credits to other refiners with more challenged refineries that need to 

purchase credits to assist with compliance.

5.1.1.6. In-Use Gasoline

What Commenters Said:

Commenter: National Automobile Dealers Association (NADA)

Importantly, dealerships and their customers deserve to know that state-of-the-art emissionsrelated components and systems will not be undermined by substandard or ‘bad’ fuels. Thus, it is 

incumbent upon EPA to set appropriate limits on motor fuel characteristics in order to enable 

effective vehicle emissions control and to protect in-use vehicle performance against substandard 

or inappropriate real-world fuels. 

Our Response:

With regard to concerns about in-use sulfur levels, we believe that vehicles will see sulfur 

levels closer to the 10 ppm average rather than the 80 ppm cap due to the fact that the 10 ppm 

average will drive reductions in gasoline sulfur levels. As discussed further in Chapter 5.1.2 

below, we believe most refineries will still average less than 20 or 30 ppm in their physical 

gasoline production. Further, our cost analysis (in Section VII.B of the preamble to the final 

rule) projects that nearly 40% of the gasoline pool will be at 5 ppm, about 45% at 10 ppm, and 

the remaining 15% at levels higher than 10 ppm. Thus, the majority of in-use sulfur levels are 

expected to be at or below 10 ppm sulfur. And as discussed in Section V.C.1.b of the preamble, 

we are committing to monitor and further evaluate in-use sulfur levels and their impact on 

vehicle emissions. If it is warranted, we will reassess the sulfur cap level and the need for 

potential future regulatory action.

Further, while we are taking action to require lower sulfur content in in-use gasoline 

(which emissions test fuel should reflect) under authority given in Clean Air Act sections 

211(c)(1) and (2), any action related to other in-use fuel standards is outside the scope of this 

rulemaking.”
Chapter 5: Tier 3 Fuel Sulfur Program

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5.1.2. Per-Gallon and Downstream Sulfur Caps

We received comments on both of the proposed per-gallon cap options of 80/95 ppm and 50/65 ppm, 

as well as comments on finalizing lower caps of 20/25 ppm and a 20 ppm overall cap. Comments 

supporting lower caps noted potential environmental benefits. Comments in support of maintaining 

the current Tier 2 caps cited concerns on cost, flexibility for turnarounds/unplanned shut downs (due 

to refinery fire, natural disaster, etc.), and potential impacts on gasoline supply and pricing.

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

We also support reducing the refinery gate and retail pump per gallon caps to 20 and 25 ppm 

respectively for an interim time period, rather than leaving them at Tier 2 levels (80 and 95 ppm 

respectively), or partially reducing them to 50 and 65 ppm, respectively.

In the final rule, EPA should also reduce the per-gallon refinery gate and retail pump cap to 20 

and 25 ppm, respectively.

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

API and AFPM support EPA’s proposed option for maintaining the current per gallon sulfur 

caps: 80-ppm at the refinery gate and 95-ppm downstream. As EPA notes, the annual average 

sulfur standard is a factor that limits the amount of sulfur in gasoline; per gallon caps are 

important to manage planned and unplanned refinery unit downtime.

Commenter: ExxonMobil

If the Agency decides to proceed with this rulemaking, we recommend that EPA retains the 

sulfur caps at the current levels of 80 ppm at the refinery gate and 95 ppm downstream.

Commenter: Kinder Morgan Transmix Company, LLC

Yes, we support EPA’s proposed downstream cap implementation date of 2020. We concur that 

based upon a 2017 refinery gate cap of 50-ppm, transmix processors would have sufficient time 

to evaluate the impact of the regulation on our operations prior to 2020. 

Commenter: General Motors LLC (GM)

In the final rule, EPA should also reduce the per-gallon refinery gate and retail pump cap to 20 

and 25 ppm, respectively.
Tier 3 Summary and Analysis of Comments

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Commenter: Manufacturers of Emission Controls Association (MECA)

MECA is supportive of a 20 ppm gasoline sulfur cap for Tier 3 that would be aligned with 

California’s current gasoline sulfur cap. 

Commenter: Mercedes-Benz USA, LLC on behalf of Daimler AG

Mercedes-Benz further requests that a 20 ppm refinery gate and 25 ppm retail cap be enacted to 

ensure that a dependable, uniform fuel quality is available nationwide. 

Commenter: Natural Resources Defense Council (NRDC)

EPA should evaluate even lower the caps to add more certainty to pollution reductions from low 

sulfur gasoline. EPA requests comment on caps of 20 ppm at the refinery gate and 25 ppm 

downstream. EPA’s analysis, as discussed in the proposed rule, indicates that the 20 ppm and 25 

ppm levels will render the flexibilities of the ABT program unusable because all refineries will 

have to produce gasoline at 10 ppm, thus increasing the compliance cost of the Tier 3 program. 

There may be, however, cap levels below 50 ppm at the gate and 65 ppm downstream that would 

maintain sufficient compliance flexibility through the ABT program but also enhance 

downstream fuel quality certainty. EPA should provide an evaluation of additional cap levels and 

finalize caps tighter than 50 ppm and 65 ppm if feasible and cost-effective. 

Commenter: New York State Department of Environmental Conservation

We also believe that the per-gallon sulfur caps for gasoline can, and should, be reduced from the 

current levels of 80 ppm sulfur at the refinery gate, and 95 ppm sulfur at downstream locations. 

The per-gallon refinery gate and downstream sulfur standards should be reduced from 80 and 95 

ppm respectively to at most 50 and 65 ppm. 

In addition to an annual average of 30 ppm sulfur, the current Tier 2 standards set a per-batch 

cap of 80 ppm, and a downstream cap of 95 ppm. While proposing to reduce the annual average 

standard to 10 ppm sulfur, EPA proposes to leave the ‘per-gallon’ sulfur limits unchanged, while 

requesting comment on more stringent per-gallon limits. 

The EPA should allow the current 80 ppm fuel sulfur level refinery gate cap and the 95 ppm 

downstream per gallon cap.

It is evident that many refiners need the 80 ppm fuel sulfur cap to be able to purchase credits 

while they transition to the 10 ppm average. It is also evident that the full emission reduction 

potential for Tier 3 vehicles claimed in the proposed rule cannot be realized if the caps are kept 

indefinitely at the 80 ppm level. EPA should consult with the refining industry to develop a 

phase-in schedule to lower the caps to the 20 ppm to 30 ppm level by the year 2025, when Tier 3 

vehicles will comprise most of the in-use fleet. 
Chapter 5: Tier 3 Fuel Sulfur Program

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Our Response:

The final Tier 3 program retains the 80 ppm per-gallon refinery gate and 95 ppm pergallon downstream caps that are currently in place under the Tier 2 program. As discussed in 

more detail in Chapters 5.1.2.1 through 5.1.2.3 below, and in Section V.C of the preamble to the 

final rule, we believe this is the most prudent approach for lowering in-use sulfur while 

maintaining refinery flexibility, considering cost and other factors (such as refinery turnarounds, 

unplanned upsets, etc.). The per-gallon caps provide an upper limit on the sulfur concentration 

that vehicles must be designed to tolerate, and they also limit downstream sulfur contamination 

and enable the enforcement of the gasoline sulfur standard in-use.

With regard to concerns about in-use sulfur levels, we believe that vehicles will see sulfur 

levels closer to the 10 ppm average rather than the 80 ppm cap due to the fact that the 10 ppm 

average will drive reductions in gasoline sulfur levels. As discussed further in Chapter 5.1.2 

below, we believe most refineries will still average less than 20 or 30 ppm in their physical 

gasoline production. Further, our cost analysis (in Section VII.B of the preamble to the final 

rule) projects that nearly 40% of the gasoline pool will be at 5 ppm, about 45% at 10 ppm, and 

the remaining 15% at levels higher than 10 ppm. Thus, the majority of in-use sulfur levels are 

expected to be at or below 10 ppm sulfur. And as discussed in Section V.C.1.b of the preamble, 

we are committing to monitor and further evaluate in-use sulfur levels and their impact on 

vehicle emissions. If it is warranted, we will reassess the sulfur cap level and the need for 

potential future regulatory action.

5.1.2.1. Sulfur Cap Impacts on Vehicle Emissions and Enabling New Vehicle 

Technology (GHG, GDI, etc.)

We received comments on both of the proposed per-gallon cap options of 80/95 ppm and 

50/65 ppm, as well as comments on finalizing lower caps of 20/25 ppm and a 20 ppm overall cap.

Comments supporting lower caps noted greater certainty that vehicles would see lower and more 

uniform gasoline sulfur levels, and enabling new vehicle technologies that require very low sulfur 

levels. Comments against lower caps disagreed with the effect of sulfur levels on vehicle 

technologies and asserted that sulfur effects on such technologies were largely reversible.

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Furthermore, automakers support EPA reducing the retail per gallon cap to at least 25 ppm, 

which is close to the 20 ppm cap in California and should be feasible to achieve nationwide in 

the foreseeable future. 

The auto industry supports EPA’s proposed reduction of the annual refinery average sulfur limit 

for gasoline in the proposed Tier 3 rule, but we also support further reduction in the other two 
Tier 3 Summary and Analysis of Comments

5-35

prongs of the federal market gasoline sulfur standard, the per gallon cap at the refinery gate, and 

the per gallon cap downstream at the retail pump. 

However, while we commend EPA for proposing reduction of annual average sulfur content in 

gasoline, the proposed rule does not go far enough in reducing the absolute cap on downstream 

levels of this harmful component. As proposed, the rule does little to assure that there is uniform 

gasoline sulfur content at the gas pump. Automakers need a clear, harmonized standard, with 

consistently low sulfur levels at the pump to optimize vehicle technology to meet the emissions 

reductions and GHG/fuel economy goals set by the Agency, and thus request that EPA take 

further action on sulfur to facilitate compliance with such requirements. 

In the proposed rule, EPA has focused on reducing the annual refinery average for sulfur from 30 

ppm to 10 ppm (38). While reducing this annual average is important, without a concurrent 

reduction in the other two prongs of the standard the rule does not achieve a predictable capped 

amount of sulfur in each gallon of gasoline. 

EPA is considering leaving in place the Tier 2 refinery gate per-gallon cap at 80 ppm and the 

per-gallon downstream cap at 95 ppm, and indeed has written the proposed C.F.R. regulatory 

language based on this approach (39). However, the Agency is also taking comment on reducing 

the refinery gate per-gallon cap to 50 ppm [or 20 ppm], and the downstream per-gallon cap to 65 

ppm [or 25 ppm] (40). As EPA’s own data show, the lower the sulfur the better, and we support 

the lowest possible levels for these latter two standards. 

Predictable, low, downstream levels of sulfur are necessary for vehicles to run on the most 

advanced engine/emissions control systems, and OEMs need assurance of such levels to 

facilitate long-term product planning. 

The highest sulfur level recorded among gasoline in the contiguous U.S. in the July 2012 

Alliance fuels survey was 43 ppm, (41) and in the January 2013 survey was 72 ppm. Only 1 of 

the 394 retail samples in January 2013 exceeded 65 ppm, suggesting that EPA would be able to 

transition the refinery gate and retail pump cap limits without imposing significant costs. A retail 

sulfur cap of 25 ppm should be workable within the time period covered in the rule. As discussed 

below, this change would also come closer to harmonization with California’s 20 ppm sulfur 

retail cap (42). 

It will not be possible for emissions control equipment to work at the required levels found 

within Tier 3 while operating with sulfur as high as 95 ppm. Therefore a predictable national 

sulfur standard at the point of sale to the consumer, the retail pump, is crucial for ensuring that 

vehicles will have the fuel they need to meet the required fuel economy increases and emissions 

reductions. 

EPA’s own new study data show clear benefits from reducing gasoline sulfur from 28 ppm to 5 

ppm (43). The remaining issues are technical and economic feasibility for establishing a more 

stringent sulfur cap at retail. EPA’s own data shows catalyst sulfur poisoning reversibility is 

limited, and reduced sulfur in the fuel provides better emissions reductions (44). EPA must take 

action to reduce the per-gallon retail cap of sulfur to 25 ppm to support the OEMs’ emissions 
Chapter 5: Tier 3 Fuel Sulfur Program

5-36

reduction requirements, and also to plan for adjustments to achieve a 10 ppm retail sulfur cap as 

soon as possible, as noted above.

38 - 78 Fed. Reg.29908 at 29921 (May 21, 2013).

39 - 78 Fed. Reg. 29908 at 30023-30024 (May 21, 2013).

40 - 78 Fed. Reg. 29908 at 29920 (May 21, 2013).

41 - Annual Alliance of Automobile Manufacturers North American Fuels Survey, July 2012.

42 - California Reformulated Gasoline Regulations, 13 C.C.R. §2262.

43 - See EPA study, “The Effects of Gasoline Sulfur Level on Emissions from Tier 2 Vehicles in the InUse Fleet,” April 2013.

44 - Id.

Commenter: American Fuel & Petrochemical Manufacturers (AFPM)

The AFPM recommends that the current refinery gate cap for gasoline remain at 80 ppm sulfur.

This would not interfere with an engine technology. Even the Agency has proposed that 80 ppm 

is prudent for 2017 to 2019.

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

API engaged Turner, Mason & Company (TM&C) to evaluate the economic, supply, and overall 

gasoline pool quality implications for imposing more stringent per-gallon sulfur caps on U.S. 

gasoline in addition to the assumed reduction in the annual average sulfur limit to 10 ppm. (33) 

The complete TM&C report titled “Economic and Supply Impacts of a Reduced Cap on Gasoline 

Sulfur” has been submitted as Attachment No. 12.

The automakers have expressed concern about potential impacts on emissions performance if 

individual vehicles are exposed to gasoline above 10 ppm S. We believe that this concern is 

unfounded. The per-gallon limits on the concentration of sulfur in gasoline should not be 

changed from the current levels of 80 ppm at the refinery gate and 95 ppm downstream. 

Research recently completed by SGS Environmental Testing Corp. indicates that the increase in 

exhaust emissions from late model vehicles exposed to as much as 80 ppm S in gasoline is fully 

reversible within a short period of time (i.e., ~70 miles of driving) following a return to operation 

on gasoline containing 10 ppm S (34). The study has been submitted as Attachment No. 11 for 

EPA’s review. 

The API study focused on six passenger cars, of which five were certified to California SULEV 

II/PZEV emissions standards, and one vehicle which complied with the federal Tier 2/Bin 5 

exhaust emissions standard. The test vehicles represented a range of emission control and engine 

technologies and were equipped with catalytic convertors that had been aged to the equivalent of 

120,000 to 150,000 miles of driving. The reversibility test sequence included: (a) four baseline 

emissions tests run on 10 ppm S fuel, (b) three tests using 80 ppm S gasoline following 300 

miles of operation on this high sulfur fuel, and (c) three tests after the vehicles were switched 

back to 10 ppm S fuel. The base fuel was a California LEVIII certification gasoline containing 

10% ethanol by volume. The 80 ppm S fuel was produced by doping the base fuel with a 

representative mixture of sulfur compounds. 
Tier 3 Summary and Analysis of Comments

5-37

Figure 13 [of EPA-HQ-OAR-2011-0135-4276-A2] evaluates the reversibility of the sulfur 

effects by comparing emissions before and after the exposure to 80 ppm fuel. The mean 

emissions after the exposure to the high sulfur fuel are subtracted from the mean emissions for 

the initial baseline on 10 ppm sulfur fuel, 95% confidence intervals are calculated for the 

difference, and the results are plotted for each of the six individual test vehicles and for the fleet 

as a whole. If the confidence interval for the emissions difference does not include zero, then 

emissions on 10 ppm sulfur fuel after exposure to 80 ppm fuel are statistically different from the 

initial 10 ppm baseline. If the entire confidence interval is less than zero then emissions are 

statistically higher after exposure to 80 ppm sulfur, indicating that sulfur effects are not fully 

reversible. If the confidence interval includes zero, then mean emissions before and after 

exposure to the 80 ppm fuel are not statistically different and the hypothesis that the sulfur 

effects on emissions were irreversible would be rejected. 

Based on the statistical analysis of the results as summarized in Figure 13, the study concluded 

that, for each vehicle tested and for the test fleet as a whole, the change in NMOG, NOx, CO, 

Soot and PM emissions resulting from exposure to 80 ppm S fuel was quickly reversed upon 

returning to operation on 10 ppm S gasoline. There was greater than 95% confidence that the 

differences in the mean emissions values measured before and after the high sulfur fuel exposure 

were not statistically different.

33 - Auers, J.R. et al.Turner, Mason & Company Consulting Engineers, Economic and Supply Impacts of 

a Reduced Cap on Gasoline Sulfur Content, February 2013.

34 - SGS Environmental Testing Corp., Reversibility of Gasoline Sulfur Effects on Exhaust Emissions 

From Late Model Vehicles, prepared for American Petroleum Institute, June 2013

Commenter: Appalachian Mountain Club (AMC)

Related to this provision, AMC supports EPA’s proposed option to lower the per-gallon sulfur 

caps to 50 ppm at the refinery gate and 65 ppm downstream in 2020. This provision allows 

flexibility for some refiners but will also provide opportunities for advancements in the 

automobile technologies that result in lower emissions. 

Commenter: BMW of North America, LLC

We also recommend that EPA promulgate a final rule that reduces the refinery gate and 

downstream sulfur caps to 20 and 25 ppm, respectively, to ensure low levels of sulfur at the retail 

pump. 

Commenter: Chrysler Group LLC

In addition to EPA’s 10 ppm sulfur national average gasoline, Chrysler urges EPA to adopt 20 

ppm refinery sulfur and 25 ppm retail sulfur caps. Having a predictable national standard at the 

retail pump is crucial for vehicle design and development to achieve intended GHG and fuel 

economy benefits from lean-burn GDI systems. Again, without low sulfur (both national refinery 

average and at retail), lean-burn GDI systems will be subject to more frequent regeneration 

events leading to significant fuel economy (and corresponding GHG) penalties.
Chapter 5: Tier 3 Fuel Sulfur Program

5-38

Recommendation: Chrysler recommends that EPA adopt a 20 ppm refinery sulfur cap coupled 

with a 25 ppm downstream (retail) sulfur cap.

Commenter: Emissions Control Technology Association (ECTA)

Given EPA’s two options regarding per-gallon sulfur caps, we agree with EPA’s 

recommendation for lowering the caps from 80 ppm at the refinery gate (and 95 ppm 

downstream) to 50 ppm at the refinery gate (and 65 ppm downstream) (3). EPA’s other option of 

maintaining the current caps is not acceptable for two reasons: First, it will have a negative 

impact on the performance and durability of emissions and catalyst systems, as explained above. 

Secondly, reducing the caps in EPA’s proposal from 80 ppm at the refinery gate (and 95 ppm 

downstream) to 50 ppm at the refinery gate (and 65 ppm downstream) would not materially 

increase the cost of compliance to refineries. Under the EPA’s cost model that assumes intracompany trading only, just eight refineries consume credits rather than reduce their sulfur levels 

down to 10 ppm. To the extent that the current level of sulfur for each of these refineries is less 

than 50 ppm—a highly likely outcome given the nationwide average of 21 ppm according to 

MOVES 2010 data—then requiring these refineries to reduce the sulfur content to 50 ppm is a 

non-binding constraint that would impose no incremental costs. 

Because EPA’s cost model did not permit refineries to choose sulfur levels between their current 

levels and 10 ppm, one can infer that for these eight refineries that choose to consume credits and 

maintain their current sulfur levels, the associated compliance cost would be less than the cost of 

achieving 10 ppm. It is possible, however, that for those refineries, the cost of reducing sulfur 

slightly, to say 20 or 25 ppm, and consuming fewer credits would be an even better option. If so, 

then compelling these refineries to achieve at most 50 ppm would not impose any additional 

compliance costs. 

Fortunately, it is possible to estimate an upper bound on the incremental compliance costs 

associated with imposing a cap of 50 ppm. Assuming conservatively that all eight of these 

refineries currently generate sulfur in excess of 50 ppm, one can estimate the upper bound by 

comparing EPA’s no-ABT scenario with its limited ABT scenario: $2.527 billion (or 0.97 cents 

per gallon) versus $2.203 billion (0.89 cents per gallon), a difference of just $324 million. In 

other words, forcing these eight refineries to achieve 10 ppm generates an added cost of $324 

million relative to a system with limited credit trading. Because EPA’s proposed caps would 

require these eight refineries to achieve a more modest 50 ppm, the expected incremental 

compliance cost would range from $0 (assuming either they are already below 50 ppm, or they 

are above 50 ppm but prefer reducing sulfur slightly and consuming fewer credits) to $324 

million (assuming they are above 50 ppm and prefer to stay above 50 ppm and consume more 

credits). 

Indeed, the same comparison provides the upper bound of incremental compliance costs for any 

cap up to 10 ppm, including EPA’s alternative 20 ppm cap. Accordingly, so long as the social 

benefits of imposing a cap of either 20 ppm or 50 ppm exceed $324 million, then the EPA should 

impose a more stringent cap than 80 ppm. EPA notes that a higher cap means that vehicles still 

have to be designed to operate on high-sulfur fuel, which would undermine emission 

performance and likely increase the cost of compliance for automobile manufacturers.4 Because 
Tier 3 Summary and Analysis of Comments

5-39

the benefits of greater emission compliance increase with the cap stringency—a more stringent 

cap generates less variability in sulfur levels—it is conceivable that a 20 ppm cap (which would 

allow little variability in sulfur levels) would generate greater net surplus than a 50 ppm cap 

(which would allow substantial variability). 

3 - Id. at 29927.

4 - Id. at 29927.

Commenter: Marathon Petroleum Company LP (MPC)

The automakers have expressed concern about potential impacts on emissions performance if 

individual vehicles are exposed to gasoline above 10 ppm S. We believe that this concern is 

unfounded. The per-gallon limits on the concentration of sulfur in gasoline should not be 

changed from the current levels of 80 ppm at the refinery gate and 95 ppm downstream. 

Research recently completed by API indicates that the increase in exhaust emissions from late 

model vehicles exposed to as much as 80 ppm S in gasoline is fully reversible within a short 

period of time (i.e., ~70 miles of driving) following a return to operation on gasoline containing 

10 ppm S. (21)

The API study focused on six passenger cars, of which five were certified to California SULEV 

II/PZEV emissions standards, and one vehicle which complied with the federal Tier 2/Bin 5 

exhaust emissions standard. The test vehicles represented a range of emission control and engine 

technologies and were equipped with catalytic convertors that had been aged to the equivalent of 

120,000 to 150,000 miles of driving. The reversibility test sequence included: (a) four baseline 

emissions tests run on 10 ppm S fuel, (b) three tests using 80 ppm S gasoline following 300 

miles of operation on this high sulfur fuel, and (c) three tests after the vehicles were switched 

back to 10 ppm S fuel. The base fuel was a California LEVIII certification gasoline containing 

10% ethanol by volume. The 80 ppm S fuel was produced by doping the base fuel with a 

representative mixture of sulfur compounds.

Figure 11 (below) evaluates the reversibility of the sulfur effects by comparing emissions before 

and after the exposure to 80 ppm fuel. The mean emissions after the exposure to the high sulfur 

fuel are subtracted from the mean emissions for the initial baseline on 10 ppm sulfur fuel, 95% 

confidence intervals are calculated for the difference, and the results are plotted for each of the 

six individual test vehicles and for the fleet as a whole. If the confidence interval for the 

emissions difference does not include zero, then emissions on 10 ppm sulfur fuel after exposure 

to 80 ppm fuel are statistically different from the initial 10 ppm baseline. If the entire confidence 

interval is less than zero then emissions are statistically higher after exposure to 80 ppm sulfur, 

indicating that sulfur effects are not fully reversible. If the confidence interval includes zero, then 

mean emissions before and after exposure to the 80 ppm fuel are not statistically different and 

the hypothesis that the sulfur effects on emissions were irreversible would be rejected.

Based on the statistical analysis of the results as summarized in Figure 13, the study concluded 

that, for each vehicle tested and for the test fleet as a whole, the change in NMOG, NOx, CO, 

Soot and PN emissions resulting from exposure to 80 ppm S fuel was quickly reversed upon 

returning to operation on 10 ppm S gasoline. There was greater than 95% confidence that the 

differences in the mean emissions values measured before and after the high sulfur fuel exposure 
Chapter 5: Tier 3 Fuel Sulfur Program

5-40

were not statistically different. 

21. SGS Environmental Testing Corp., Reversibility of Gasoline Sulfur Effects on Exhaust Emissions 

From Late Model Vehicles, prepared for American Petroleum Institute, June 2013 

Commenter: Mercedes-Benz USA, LLC on behalf of Daimler AG

The impact of a 10 ppm retail average limit in the Tier 3 proposal...and can be strengthened by 

reducing the current refinery gate and retail sulfur caps to 20 and 25 ppm, respectively. 

Commenter: Michigan Department of Environmental Quality (MDEQ)

Because poisoning of the catalyst can occur when larger amounts of sulfur are in the fuel and 

these poisonings may, in some instances, be irreversible, the MDEQ, Air Quality Division 

advocates the modification of the current refinery gate and downstream caps of 80 ppm and 95 

ppm, respectively. The MDEQ, Air Quality Division would prefer the USEPA chose to lower the 

refinery gate and downstream caps to 50 ppm and 65 ppm, respectively. The downstream sources 

of sulfur should be able to take steps to decrease sulfur contamination, and have no incentive if 

the caps remain where they currently are. 

Commenter: New York State Department of Environmental Conservation

While catalyst sulfur poisoning is to a degree reversible, restoration of catalyst activity is not 

instantaneous. High sulfur gasoline batches may have a negative impact on in-use emissions 

beyond the fraction of the gasoline pool they represent. Given that the total amount of sulfur in 

the gasoline pool will be reduced, the per-gallon maximum levels should also be reduced. These 

levels should be set no higher than 50 ppm sulfur at the refinery and 65 ppm sulfur downstream. 

Lower levels should be considered. 

We concur with EPA that this change should take effect in 2020. 

Commenter: Sierra Club, Clean Air Watch, Respiratory Health Association

It is important to note that EPA is proposing an average sulfur standard of 10 ppm. However, the 

actual sulfur content of fuel can vary substantially, based on variations in refinery operations and 

contamination from gasoline being transported through pipelines to its final destination. 

Automakers must then design vehicles to function with higher-sulfur gasoline. In order to give 

certainty to automakers designing vehicles and to ensure emissions reductions, setting caps on 

per-gallon sulfur content is critical. 

We urge EPA, as it lowers the average sulfur standard from 30 ppm to 10 ppm, to also lower the 

per-gallon sulfur caps to at least 50 ppm at the refinery gate and 65 ppm downstream. 

Lowering the per-gallon caps will allow automakers to employ additional advanced vehicle 

technologies that can increase vehicle efficiency and lower emissions, while still allowing 

compliance flexibility for refiners. 
Tier 3 Summary and Analysis of Comments

5-41

Commenter: Union of Concerned Scientists (UCS)

Lowering the per-gallon caps from 80 ppm at the refinery gate (and 95 ppm downstream) to 50 

ppm at the refinery gate (and 65 ppm downstream) would not materially increase the cost of 

compliance to refineries. Under the EPA’s cost model, no refineries would be producing product 

over 50 ppm per-gallon due to the 10 ppm average target, and only one refinery would likely be 

over 40 ppm (6). Therefore, requiring these refineries to meet a 50 ppm per-gallon cap would 

impose no incremental costs under normal operations, and would further ensure public health 

protections by minimizing the impacts of the sulfur on the performance and durability of the 

catalytic converter. 

Commenter: Volkswagen Group of America, Inc.

As automakers, we must constantly balance market fuel availability and vehicle durability when 

deciding on which concepts to bring to the US market. Having caps on things such as sulfur set 

low enough would allow a range of vehicle technologies to be offered in a wide variety of 

products. A 10 ppm cap is appropriate, but we support 20 ppm & 25 ppm caps at the refinery 

gate and downstream, respectively. 

Tier 3 vehicle emission standards are arguably the most stringent on earth; OEMs must have the 

most state-of-the-art fuels to support the state-of-the-art vehicles. Therefore, VW supports 

reductions in market fuel sulfur measured at the pump to a maximum 10 ppm. Other areas of the 

world with less-strict regulations already have very low sulfur market gasoline. 

Our Response:

As explained in Section V.C.b of the preamble to the final rule, we are retaining the 

current Tier 2 80 ppm refinery gate cap. The refinery gate cap provides flexibility for batch-tobatch variability that naturally occurs at a refinery due to the varying types of crude that 

refineries process, variations in unit operations, and variations in product mix. It further provides 

for flexibility during unit turnarounds, and unplanned upsets (e.g., refinery fires, natural 

disasters, etc.), to avoid a complete refinery shutdown. A lower cap could create situations where 

refiners would need to store more off-spec gasoline for future processing. However, if a refinery 

does not have adequate tankage for storing this product, and/or if its processing units are not 

large enough to “catch up” in refining off-spec product, it could result in significant impacts to 

fuel pricing or supply. For a refiner that produces multiple products, any potential supply impacts 

could also impact other fuel markets (e.g., diesel, jet fuel, etc.). Additionally, the refinery gate 

cap is a “hard” limit—a refinery’s actual production has to be well below this limit to account for 

in-use testing tolerances, safety margins, and any additives that a refiner may need to add prior to 

the fuel leaving the refinery. An 80 ppm refinery gate cap will provide refiners needed 

flexibility, and more certainty that they will be able to continue producing and distributing at 

least some gasoline during turnarounds/upsets to avoid a total shutdown. It will further provide 

more certainty for transmix processors, additive manufacturers and other downstream parties. 

As also described below in Section VII of the preamble to the final rule, we believe that 

most refineries will be able to meet the 10 ppm average sulfur standard largely through revamps 
Chapter 5: Tier 3 Fuel Sulfur Program

5-42

and operational changes at their facilities, rather than installing grassroots units. Lowering to a 

cap of 50 ppm would directionally increase the costs of the Tier 3 program. They provided a 

detailed study quantifying the additional costs associated with successively more stringent pergallon caps. While we do not agree with the study’s overall cost analysis, we do agree that with a 

refinery gate cap of 50 ppm, a number of refiners would incur higher capital costs due to the 

decreased ability to handle off-spec product with a lower refinery gate cap. As refiners must 

ensure that they can continue to produce saleable product and meet demand in the event of an 

upset or an off-spec batch of fuel, the need for installation of additional tankage and/or increased 

refinery processing capability would be greater with a 50 ppm refinery gate cap. While at the 

time of the proposal we believed that a cap of 50 ppm would have little cost impact, our more 

recent analysis shows that a 50 ppm cap would increase the cost of the Tier 3 gasoline sulfur 

standards by approximately 10 percent (see RIA Chapter 5.2.2.4).At the same time, the more 

stringent cap with its associated increase in cost would be unlikely to provide significant 

additional emission benefits nationwide. As discussed previously in Sections III and IV of the 

preamble, the emissions benefits associated with the Tier 3 program are mainly driven by the 

reduction in the average sulfur content of gasoline from 30 to 10 ppm, since vehicle emissions 

are proportional to the sulfur content of the fuel. Changes in the cap would not affect this. In the 

context of the final ABT provisions, a higher cap does allow for increases in emissions on a 

temporal basis as one batch of fuel is allowed to have higher sulfur levels. However, this is then 

offset by reductions in emissions from batches of fuel that are then required to be below the 10 

ppm average standard. Similarly, the final ABT provisions allow for the possibility that the fuel 

from different refineries will cause varying emission reductions as one refinery’s higher average 

sulfur levels would lead to less emission reductions in-use. However, this is then offset by 

greater reductions in emissions due to the fuel produced by refineries with sulfur levels below 

the average standard. In sum, we continue to believe that vehicles will see sulfur levels closer to 

the 10 ppm average rather than the 80 ppm cap due to the fact that the 10 ppm average will drive 

reductions in gasoline sulfur levels.

Thus, we believe it is prudent at this time to retain an 80 ppm refinery gate cap. 

However, we are committing to monitor and further evaluate in-use sulfur levels and their impact 

on vehicle emissions. If it is warranted, we will reassess the sulfur cap level and the need for 

potential future regulatory action. Such ongoing evaluation will include analyses of in-use fuel 

surveys, batch data that refineries are required to submit, and the sulfur credit market. It will 

also include an evaluation of any issues or concerns that might arise during implementation of 

the program. Finally, we will also carry out an ongoing evaluation of data submitted by the 

vehicle manufacturers on the performance of their Tier 3 vehicles in-use.

As also discussed in Section IV.A.6 of the preamble to today’s final rule, we believe the 

80 ppm sulfur cap is sufficient to allay concerns over irreversibility or sulfur poisoning.

5.1.2.2. Impacts of Lower Caps on Fuel Supply/Cost

We received comments on both of the proposed per-gallon cap options of 80/95 ppm and 

50/65 ppm, as well as comments on finalizing lower caps of 20/25 ppm and a 20 ppm overall 

cap. Comments in support of maintaining the current Tier 2 caps cited concerns on cost, flexibility 
Tier 3 Summary and Analysis of Comments

5-43

for turnarounds/unplanned shut downs (due to refinery fire, natural disaster, etc.), and potential 

impacts on gasoline supply and pricing.

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

The highest sulfur level recorded among gasoline in the contiguous U.S. in the July 2012 

Alliance fuels survey was 43 ppm, (41) and in the January 2013 survey was 72 ppm. Only 1 of 

the 394 retail samples in January 2013 exceeded 65 ppm, suggesting that EPA would be able to 

transition the refinery gate and retail pump cap limits without imposing significant costs. A retail 

sulfur cap of 25 ppm should be workable within the time period covered in the rule. As discussed 

below, this change would also come closer to harmonization with California’s 20 ppm sulfur 

retail cap (42). 

41 - Annual Alliance of Automobile Manufacturers North American Fuels Survey, July 2012.

42 - California Reformulated Gasoline Regulations, 13 C.C.R. §2262.

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

API and AFPM support EPA’s proposed option for maintaining the current per gallon sulfur 

caps: 80-ppm at the refinery gate and 95-ppm downstream. As EPA notes, the annual average 

sulfur standard is a factor that limits the amount of sulfur in gasoline; per gallon caps are 

important to manage planned and unplanned refinery unit downtime. 

Beyond the refinery gate, the introduction of sulfur into gasoline occurs during pipeline shipment 

through multiproduct pipelines and back-to-back shipments with higher sulfur content jet fuel. A 

recent study by Turner Mason shows that reductions below the current sulfur cap standards, will 

result in even higher capital costs, reduced compliance flexibility, and potential loss of gasoline 

supplies. 

API and AFPM support EPA’s first proposed option for maintaining the current per gallon sulfur 

caps: 80-ppm refinery gate sulfur cap and 95-ppm downstream sulfur cap. As EPA notes, the 

annual average sulfur standard is a factor that limits the amount of sulfur in gasoline, and also 

that per gallon caps have an important role. Beyond the refinery gate, the introduction of sulfur 

into gasoline occurs during pipeline shipment through multiproduct pipelines and back-to-back 

shipments with higher sulfur content jet fuel. 

However, it is important to understand potential impacts of tighter per gallon sulfur caps on 

compliance cost and supply impacts. A tighter per gallon sulfur cap, either with the current 

annual average sulfur limit or a tighter standard as proposed for Tier 3, results in less flexibility 

and could lead to supply reductions. This is because that in addition to downstream sulfur 

introduction into gasoline, increased sulfur can occur inside the refinery gate due to planned or 

unplanned upsets, unit turnarounds or unit shutdowns. 
Chapter 5: Tier 3 Fuel Sulfur Program

5-44

Another advantage of maintaining the current per gallon sulfur cap standard is that it allows 

current transmix operations to continue. As noted by the EPA in the Tier 3 proposed rule, 

transmix that occurs from pipeline shipping accounts for only a small amount of gasoline 

consumption and most transmix batches of gasoline are approximately only 10 ppm above the 

current Tier 2, 30-ppm refinery sulfur average. This indicates that sulfur content in transmix is 

relatively small, even in the context of current refinery annual average sulfur standard. 

API engaged Turner, Mason & Company (TM&C) to evaluate the economic, supply, and overall 

gasoline pool quality implications for imposing more stringent per-gallon sulfur caps on U.S. 

gasoline in addition to the assumed reduction in the annual average sulfur limit to 10 ppm. (33) 

The complete TM&C report titled “Economic and Supply Impacts of a Reduced Cap on Gasoline 

Sulfur” has been submitted as Attachment No. 12 for EPA’s review. 

TM&C’s conclusions are summarized below: 

- The cost to manufacture gasoline will increase as the sulfur cap is reduced from the current 80 

ppm standard; capital costs range from approximately $2 billion to over $6 billion and annual 

operating costs are estimated at $900 million for a 20 ppm cap. These costs are in addition to 

those required to meet a 10 ppm annual average limit. 

- Overall potential loss of gasoline supply will increase tenfold as the sulfur cap is reduced from 

the current 80 ppm standard, resulting in 130 MBPD of supply loss at a 20 ppm cap. 

- Regions served by just a few refineries could experience shortages of 25% - 50% during 

outages of gasoline sulfur reduction units at a 20 ppm cap, while outages would be minimized at 

sulfur caps exceeding 50 ppm. 

Maintaining the current sulfur cap is a reasonable approach, but won’t lower costs very much.

33 - Auers, J.R. et al.Turner, Mason & Company Consulting Engineers, Economic and Supply Impacts of 

a Reduced Cap on Gasoline Sulfur Content, February 2013.

34 - SGS Environmental Testing Corp., Reversibility of Gasoline Sulfur Effects on Exhaust Emissions 

From Late Model Vehicles, prepared for American Petroleum Institute, June 2013

Commenter: BP Products North America Inc.

Maintain Current Sulfur Cap -BP recommends that EPA maintain the current 80 ppm refinery 

gate per gallon cap and 95 ppm downstream per gallon cap as proposed. Reducing the sulfur cap 

is unnecessary and adds to potential supply issues during turnarounds and upsets. 

Commenter: Chevron Products Company

If EPA proceeds with the gasoline sulfur reduction, we do support several of the proposed 

elements including: per gallon sulfur cap.

We agree that the most appropriate per-gallon cap would be Cap Option 1, to maintain the 

existing 80 ppm refinery gate cap and the existing 95 ppm downstream cap. Under a 10 ppm 

annual average, the sulfur cap will be largely self-limiting, as refiners will not be able to produce 

individual batches near the sulfur cap and still meet the annual average. An arbitrarily low sulfur 
Tier 3 Summary and Analysis of Comments

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cap like 20 or 25 ppm will result in a significant increase in capital requirements in the refinery 

and will likely decrease refinery utilization and impact the supply of gasoline to the market. 

Regarding Cap Option 2, while we do not feel that it would be necessary to reduce the refinery 

gate sulfur cap to 50 ppm with a 65 ppm downstream cap in 2020, we do not strongly oppose this 

option. A 50 ppm refinery gate cap still provides some flexibility to manage variability in the 

sulfur content of the gasoline pool without imposing too stringent of a cap. Because the 

maximum per-gallon sulfur is self-limiting due to the 10 ppm average, a 50 ppm cap would be 

reasonable. The EPA should not consider any refinery gate sulfur caps below 50 ppm regardless 

of timing. Reducing the sulfur caps to 50 ppm will add significant cost to the refinery and 

downstream systems. However, going below this level is prohibitively expensive and not 

warranted by the Tier 3 vehicle technology requirements (2). A Turner Mason & Co. study 

commissioned by API indicates a significant increase in implementation cost for a sulfur cap 

below 50 ppm. 

2 - Turner Mason & Co., ‘Economic and Supply Impacts of a Reduced Cap on Gasoline Sulfur’, 2012

Commenter: CHS, Inc.

CHS is providing the following comments regarding the Tier 3 proposed gasoline refiner gate 

per-gallon sulfur cap and downstream per-gallon sulfur cap. Although CHS prefers Cap Option 

1, we can support the lower sulfur levels in Cap Option 2. CHS does not support lowering the 

refinery gate per-gallon cap to 20 ppm sulfur and lowering the downstream per-gallon cap to 25 

ppm sulfur. These lower limits do not allow enough room for refinery unit disruptions where 

gasoline could still be produced at the higher sulfur per-gallon levels. The unintended 

consequences of the proposed lower levels will affect the consumer’s ability to buy gasoline and 

cause regional gasoline price spikes that will put unnecessary economic burden on the consumer. 

Commenter: Countrymark; Small Business Refiners (SBR)

EPA has proposed to keep the 80 ppm sulfur refinery cap in the draft regulatory text of the 

proposed rule but asked for comment on reducing this cap to 50 ppm in 2020, and potentially 

even further to 20 ppm in 2020. The SBRs are opposed to any reduction of the present cap and 

believe EPA should keep this successful flexibility provision. This flexibility will particularly 

benefit inland refiners that have limited ability to sell or ship blend stocks, should they have an 

unplanned outage of the FCC post-treater. 

EPA acknowledges in the proposed rule preamble that the unique US fuel distribution system 

needs some level of cap room to allow for:

- Refinery flexibility to produce gasoline during temporary upsets and turnarounds

- Contamination challenges posed by pipelines and terminals that must also handle jet fuel with a 

3,000 ppm sulfur specification 

- Transmix processors that need ability to inject processed material back into the system. 

With the existing 80 ppm cap, the Tier 2 sulfur rule has successfully reduced the average 

gasoline sulfur to below 30 ppm as shown in the graph provided by EPA, included in the draft 

Regulatory Impact Analysis (RIA): 
Chapter 5: Tier 3 Fuel Sulfur Program

5-46

Clearly EPA’s own analysis shows very little incentive for lowering the 80 ppm cap. Keeping 

this cap will allow refiners maximum flexibility in responding to unplanned events and outages. 

This is especially true for inland refiners that lack the ability to sell/ship blend stocks should they 

have an unplanned outage of the FCC post-treater. Lowering the cap could put the areas served 

by inland refiners at increased risk for supply disruptions with no corresponding relief in average 

gasoline sulfur level.

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

Per Gallon Caps – Retain 80/95-ppm Standards: EPA has requested comments on two options 

for the per-gallon sulfur caps. Under the first option, the Agency would retain the current 80 

ppm refinery/import gate sulfur standard and the 95 ppm downstream (terminal) sulfur cap.

Under the second option, the refinery/import gate cap would be reduced to 50 ppm and the 

downstream (terminal) cap would be set at 65 ppm. 

As EPA is aware, to ensure the continuous flow of product, refineries and importers need 

maximum flexibility. EPA recognizes that the U.S. has the longest and most complex gasoline 

distribution system in the world, making it harder to control sulfur contamination than in other 

countries. The 80/95 ppm sulfur caps provide such flexibility, allowing facilities to address 

unanticipated problems such as a malfunctioning unit or a terminal hit by a superstorm, such as 

Hurricane Sandy, or an anticipated shutting down of a unit due to a scheduled turnaround. 

Lowering the per-gallon caps to 50/65 ppm sulfur reduces that flexibility and makes it harder to 

meet supply obligations – often at times when supply is desperately needed. 

Finally, IFTOA agrees with EPA that a per-gallon standard of 20/25 ppm would be impossible 

for the industry to meet without almost all refinery facilities making substantial modifications to 

their units. Significant changes to the nation’s gasoline pipeline and terminal distribution system 

would also be required. Such modifications would certainly compound the problems, burdens 

and costs discussed above. Implementation of the annual average 10 ppm sulfur standard would 

be delayed for many years. 

Retention of the current 80/95 ppm per-gallon standards to provide maximum flexibility to the 

industry. It is unlikely that industry would produce/import, ship or distribute gasoline meeting 

those standards; however, it is important to have the ability to do so when unexpected events 

occur and strain the distribution system. 

Retain the current per-gallon sulfur caps of 80/95 ppm to provide the maximum degree of 

flexibility to address unanticipated events.

Commenter: Irving Oil Terminals Inc.

EPA is proposing either to maintain the current 80 ppm refinery gate per gallon sulfur limitation 

and the 95 ppm downstream per gallon cap or to lower them to 50 ppm and 65 ppm, respectively. 

Irving Oil recommends that EPA retain the current per gallon caps of 80/95 ppm sulfur. These 

limitations provide the most flexibility, allowing refiners to address operational problems such as 

unexpected unit shutdowns and importers to address severe weather-related disruptions to the 
Tier 3 Summary and Analysis of Comments

5-47

downstream supply chain. For example, in a ‘gasoline-short’ supply scenario, an importer could 

increase supply options beyond its typical resources. Considering the alternative options 

proposed, the 50/65 per gallon limit is achievable but will reduce supply flexibility; and the 

20/25 per gallon cap could result in a significant step-change in the level of capital investment 

required by refiners. For this reason, Irving Oil strongly opposes the proposed 20/25 per gallon 

cap. Retention of the 80/95 per gallon limits would provide as much compliance flexibility as is 

possible while achieving the new Tier 3 goals of an annual average 10 ppm sulfur content. 

Commenter: Magellan Midstream Partners, L.P.

Downstream Sulfur Cap - Under the Tier 3 gasoline sulfur program, EPA is proposing to (1) 

maintain the current 80-ppm refinery gate and 95-ppm downstream per-gallon caps or (2) reduce 

the cap to 50 and 65 ppm, respectively or (3) reduce the per-gallon caps to as low as 20 and 25 

ppm. 

Magellan Comment — We support EPA’s proposal to maintain the current per gallon sulfur 

caps, which are 80ppm at the refinery and 95ppm downstream, for the following reasons: 

The potential for downstream contamination is as prevalent today as it was at the time the Tier 2 

rules were promulgated to regulate sulfur. In the proposed rule, EPA provides an extension to 

small refiners for compliance with the reduced sulfur standards. Allowing small refiners to 

continue production of gasoline with elevated sulfur levels provides further justification for 

maintaining the existing downstream cap. We believe there will be a significant volume of 

gasoline with elevated sulfur levels regardless of the cap for other refiners. 

Lowering the downstream cap increases the chances of product outages at storage and 

distribution terminals. If there is a sulfur excursion at a refinery, the flexibility associated with a 

higher downstream cap will potentially reduce supply disruptions that could result from having 

to reprocess gasoline. 

Sulfur levels in jet fuel remain high. Major American airports rely almost entirely on pipelines, 

and have dedicated pipelines to deliver jet fuel directly to the airport. 

Maintaining the current per gallon cap allows current transmix operations to continue in certain 

markets. 

Commenter: Marathon Petroleum Company LP (MPC)

As to other specifics of the proposal, MPC agrees with EPA on the proposed cap of 80 ppm 

sulfur and notes that any cap below this level has the potential to both limit gasoline supply 

and/or increase the refinery investments required.

MPC supports EPA’s first proposed option for maintaining the current per gallon sulfur caps: 80-

ppm refinery gate sulfur cap and 95-ppm downstream sulfur cap. As EPA notes, the annual 

average sulfur standard is a factor that limits the amount of sulfur in gasoline, and also that per 

gallon caps have an important role. Beyond the refinery gate, the introduction of sulfur into 
Chapter 5: Tier 3 Fuel Sulfur Program

5-48

gasoline occurs during pipeline shipment through multiproduct pipelines and back-to-back 

shipments with higher sulfur content jet fuel. 

However, it is important to understand potential impacts of tighter per gallon sulfur caps on 

compliance cost and supply impacts. A tighter per gallon sulfur cap, either with the current 

annual average sulfur limit or a tighter standard as proposed for Tier 3, results in less flexibility 

and could lead to supply reductions. This is because that in addition to downstream sulfur 

introduction into gasoline, increased sulfur can occur inside the refinery gate due to planned or 

unplanned upsets, unit turnarounds or unit shutdowns. 

Another advantage of maintaining the current per gallon sulfur cap standard is that it allows 

current transmix operations to continue. As noted by the EPA in the Tier 3 proposed rule, 

transmix that occurs from pipeline shipping accounts for only a small amount of gasoline 

consumption and most transmix batches of gasoline are approximately only 10 ppm above the 

current Tier 2, 30-ppm refinery sulfur average. This indicates that sulfur content in transmix is 

relatively small, even in the context of current refinery annual average sulfur standard. 

API engaged Turner, Mason & Company (TM&C) to evaluate the economic, supply, and overall 

gasoline pool quality implications for imposing more stringent per-gallon sulfur caps on U.S. 

gasoline in addition to the assumed reduction in the annual average sulfur limit to 10 ppm. The 

complete TM&C report titled “Economic and Supply Impacts of a Reduced Cap on Gasoline 

Sulfur” has been submitted to the docket for EPA’s review. 

TM&C’s conclusions are summarized below:

-The cost to manufacture gasoline will increase as the sulfur cap is reduced from the current 80 

ppm standard; capital costs range from approximately $2 billion to over $6 billion and annual 

operating costs are estimated at $900 million for a 20 ppm cap. These costs are in addition to 

those required to meet a 10 ppm annual average limit. 

-Overall potential loss of gasoline supply will increase tenfold as the sulfur cap is reduced from 

the current 80 ppm standard, resulting in 130 MBPD of supply loss at a 20 ppm cap.

Commenter: Monroe Energy, LLC

Lastly, EPA should not lower the 80ppm per gallon cap. Lowering the per gallon cap is not 

necessary to accommodate any engine technology, but would force some refiners, including 

Monroe, to install additional controls that otherwise could be avoided via reliance on the credit 

market for compliance. 

Commenter: National Association of Convenience Stores (NACS) and Society of Independent 

Gasoline Marketers of America (SIGMA)

NACS and SIGMA support the proposed option for maintaining the current per gallon sulfur 

caps of 80 parts-per-million (“ppm”) at the refinery gate and 95-ppm downstream.
Tier 3 Summary and Analysis of Comments

5-49

NACS and SIGMA support EPA’s proposed option for maintaining the current per gallon sulfur 

caps of 80-ppm at the refinery gate and 95-ppm downstream. As EPA notes, pipeline transport 

inevitably introduces the potential for sulfur contamination of the gasoline being shipped through 

multiproduct pipelines. In addition, various gasoline additives also contain varying levels of 

sulfur which contribute to the overall sulfur content of gasoline. If the final rule requires further 

reductions below the current sulfur cap standards, it could result in higher capital costs for 

refineries, which inevitably are passed down to retailers and consumers through higher prices. 

The final rule should take every step possible to mitigate the adverse effect it may have on fuel 

prices. Therefore, NACS and SIGMA support maintaining the current per gallon sulfur caps. 

Commenter: PBF Energy Inc.

PBF supports the EPA option one proposal to keep per gallon sulfur cap at 80 ppm at the refinery 

gate and 95 ppm downstream. PBF facilities have been able to comply with this standard during 

any unplanned equipment outages. 

PBF is opposed to the second option on the gasoline sulfur cap of lowering the per gallon cap to 

50 ppm sulfur at the refinery gate or 65 ppm sulfur downstream or any lower per gallon sulfur 

standard. PBF will make significant investments to comply with the proposed 10 ppm annual 

sulfur standard and is not currently planning to invest further to ensure reliability at that level. In 

the event of an unplanned outage on the new equipment installed, the refineries will likely fall 

back to current gasoline product sulfur distribution levels. The EPA is aware of the sulfur content 

distribution of PBF gasoline products through our required batch reporting. In the event of an 

unplanned outage in the Northeast system there is a risk that the event could trigger a significant 

supply disruption at the 50 ppm sulfur cap level and could possibly result in product price 

increases to consumers as a result of the potential supply disruption. 

Commenter: Phillips 66 Company

We support maintaining the 80 ppm refinery gate cap. 

Phillips 66 supports maintaining the existing 80 ppm refinery gate cap as proposed. Providing an 

80 ppm cap is beneficial in several ways. A lower cap with an effective date prior to the small 

refiner/refinery compliance date would be problematic. The result would be a different sulfur cap 

for small refiners/refineries causing complications in the distribution system. Also, reductions in 

the sulfur cap could be constraining in certain operating situations. The result would be reduction 

in supply until the operating problem was resolved. 

On behalf of API, Turner, Mason & Company recently completed an evaluation entitled 

“Economic and Supply Impacts of a Reduced Cap on Gasoline Sulfur”. Phillips 66 participated 

in this study by providing TM&C with data from our refineries. The study concludes that 

additional capital costs would be required to meet a more stringent cap (in addition to capital 

requirements to meet the 10 ppm sulfur average) and that the potential for loss of supply 

increases with a reduction in the sulfur cap. API has provided a copy of this study with their 

comments for inclusion in the docket. 
Chapter 5: Tier 3 Fuel Sulfur Program

5-50

Commenter: Shell Oil Products for Shell and Motiva

EPA proposes to leave the refinery per-gallon gasoline sulfur specification at 80 ppm, but is also 

considering lowering the per-gallon specification to 50 ppm effective in 2020. EPA should not 

change the refinery per-gallon sulfur specification from the existing 80 ppm. 

A tighter per gallon sulfur cap will result in less flexibility and could lead to supply reductions. 

Maintaining the per-gallon cap would provide important flexibility in the event of planned or 

unplanned upsets, unit turnarounds or unit shutdowns, which can result in elevated sulfur levels. 

If the per-gallon cap is too low, it could result in lost volumes of gasoline during such events. 

Another advantage of maintaining the current per gallon sulfur cap standard is that it allows 

current transmix operations to continue. Transmix that occurs from pipeline shipping accounts 

for only a small amount of gasoline consumption and most transmix batches of gasoline are 

approximately only 10 ppm above the current 30-ppm refinery sulfur average. This indicates that 

sulfur content in transmix is relatively small, even in the context of current refinery annual 

average sulfur standard. 

Commenter: Sunoco Logistics Partners L.P.

In particular, we support maintaining the current 95 ppm downstream per gallon gasoline sulfur 

cap to enable the current practices of pipeline interface handling. Pipeline and terminals will 

continue to be constrained by interfaces of gasoline with jet fuel or home heating oil. Interfaces 

with 3,000 ppm sulfur product are unavoidable, thus increasing the sulfur of the gasoline. Even 

small volume interfaces with 3,000 ppm sulfur jet fuel can significantly increase the gasoline 

sulfur. The northeast states are legislating the reduction of sulfur in home heating oil, which will 

help alleviate the heating oil sulfur contribution, although no action has been taken or is being 

contemplated to reduce the sulfur in jet fuel. Therefore we would not be supportive of lowering 

the downstream sulfur cap as low as 25 ppm. Downstream facilities with the inability to change 

their operations will not be able to handle interfaces of gasoline with jet fuel. 

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

Per Gallon Sulfur Standards. EPA also proposes lowering the refinery gate per-gallon cap to 50 

ppm sulfur and the downstream per-gallon cap to 65 ppm sulfur. Such reductions and any further 

reductions may limit the availability and use of components used to blend gasoline. These 

reductions could also limit imports of gasoline. It is important that EPA preserve the current 

refinery gate and downstream caps to provide refiners, and perhaps especially gasoline 

component blenders, the necessary flexibility to meet gasoline demand. 

Commenter: Union of Concerned Scientists (UCS)

For these reasons, it is imperative that strict sulfur content limits be set on gasoline. This 

standard will protect human health and enable the next generation of vehicle technologies be 

implemented. We strongly support the EPA’s proposal to limit the annual average sulfur content 
Tier 3 Summary and Analysis of Comments

5-51

of gasoline to 10 ppm and also urge EPA to lower the refinery gate and downstream per-gallon 

sulfur caps to 50 and 65 ppm, respectively from the current levels of 80 ppm at the refinery gate 

and 95 ppm downstream.

6 - Environmental Protection Agency (EPA). 2013. Draft Regulatory Impact Analysis Tier 3 Motor 

Vehicle Emission and Fuel Standards. Online at http://www.epa.gov/otaq/documents/tier3/420d13002.pdf 

p. 4-22, accessed on June 28, 2013.

Our Response:

As explained in Section V.C.b of the preamble to the final rule, we are retaining the 

current 80 ppm refinery gate and 95 ppm downstream sulfur caps in effect under the Tier 2 

program. The refinery gate cap provides flexibility for batch-to-batch variability that naturally 

occurs at a refinery due to the varying types of crude that refineries process, variations in unit 

operations, and variations in product mix. It further provides for flexibility during unit 

turnarounds and unplanned upsets (e.g., refinery fires, natural disasters, etc.), as noted by some 

commenters, to avoid a complete refinery shutdown or supply issues. A lower cap could create 

situations where refiners would need to store more off-spec gasoline for future processing. 

However, if a refinery does not have adequate tankage for storing this product, and/or if its 

processing units are not large enough to “catch up” in refining off-spec product, it could result in 

significant impacts to fuel pricing or supply. For a refiner that produces multiple products, any 

potential supply impacts could also impact other fuel markets (e.g., diesel, jet fuel, etc.). 

Additionally, the refinery gate cap is a “hard” limit—a refinery’s actual production has to be well 

below this limit to account for in-use testing tolerances, safety margins, and any additives that a 

refiner may need to add prior to the fuel leaving the refinery. Thus, we believe that retaining the 

80 ppm refinery gate cap will provide refiners helpful flexibility, and more certainty that they 

will be able to continue producing and distributing at least some gasoline during 

turnarounds/upsets to avoid a total shutdown. Further, it will further provide more certainty for 

transmix processors, additive manufacturers and other downstream parties.

As discussed more in Section VII.B of the preamble to the final rule, lowering to a cap of 

50 ppm would directionally increase the costs of the Tier 3 program. The Turner Mason & Co. 

study cited in API and AFPM’s comment quantified the additional costs associated with 

successively more stringent per-gallon caps. Although we do not agree with the study’s overall 

cost analysis, we do agree that with a refinery gate cap of 50 ppm, a number of refiners would 

incur higher capital costs due to the decreased ability to handle off-spec product with a lower 

refinery gate cap. As refiners must ensure that they can continue to produce saleable product and 

meet demand in the event of an upset or an off-spec batch of fuel, the need for installation of 

additional tankage and/or increased refinery processing capability would be greater with a 50 

ppm refinery gate cap. While at the time of the proposal we believed that a cap of 50 ppm would 

have little cost impact, our more recent analysis shows that a 50 ppm cap could increase the cost 

of the Tier 3 gasoline sulfur standards (see RIA Chapter 5.2.2.4). At the same time, the more 

stringent cap (with its associated increase in cost) would be unlikely to provide significant 

additional emission benefits nationwide.

5.1.2.3. Air Quality and Local Impacts of Sulfur Cap Levels
Chapter 5: Tier 3 Fuel Sulfur Program

5-52

We also received comments arguing that lower caps of 20/25 ppm and a 20 ppm overall cap 

would address “hot spots” that tend to have higher than average sulfur levels. 

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

The Alliance fuel surveys also demonstrate that the absence of a low downstream sulfur cap 

facilitates the creation of “hot spots” with higher than average sulfur content. However, these hot 

spots appear to be geographically transient over time, as confirmed by the differences just 

between July 2012 and January 2013 sampling, suggesting that there are not predictable 

locations that consistently struggle to meet sulfur limits. Nonetheless higher sulfur locations do 

occur regularly. This underscores the uncertainties for OEMs building vehicles for a nationwide 

market. 

Commenter: American Lung Association

Lower the sulfur caps. The American Lung Association supports lowering the per-gallon sulfur 

caps to 20 ppm at the refinery gate and 25 ppm downstream from the current 80 ppm per gallon 

refinery gate and 95 ppm per-gallon downstream caps in 2020. Although EPA is setting an 

average sulfur gasoline standard of 10 ppm, there will be refinery-by-refinery differences in the 

sulfur content of fuel due to operational differences. Additionally, fuel can be contaminated 

during transportation through pipelines to its final destination. As a result, the fuel quality 

available may differ by location exposing some populations to higher tailpipe emissions than 

others. EPA should set the refinery gate cap and downstream cap to 20 ppm per gallon and 25 

ppm per gallon respectively to limit the exposure of vehicles in-use to sulfur levels that 

significantly degrade pollution control performance and to ensure all communities enjoy the 

benefits of cleaner air. 

Commenter: Consumers Union

EPA’s modeling indicates that regardless of the downstream sulfur cap selected between the two 

options being considered (95 ppm or 65 ppm), nearly all gasoline that ends up at the pump would 

be close to the 10 ppm average required of refineries. Automakers will provide insight into any 

burdens that a higher downstream cap may place on them to design vehicles that can tolerate the 

higher upper limit. Although sulfur-induced corrosion of catalytic converters is largely reversible 

if lower sulfur gasoline is used with regularity (justifying the averaging approach), if there are 

retail hot spots or regional high-sulfur clusters that consistently sell gasoline towards the upper 

limit, car owners in these areas may find their catalytic converters fail at a higher rate, and 

emissions may be significantly higher in such locales. 

Commenter: CountryMark Cooperative, Small Business Refiners (SBR)
Tier 3 Summary and Analysis of Comments

5-53

EPA’s own analysis in the RIA of the proposed nation-wide credit trading program predicts that 

only 17% of the gasoline volume, mostly from smaller than average refineries, would exceed the 

10 ppm standard and the vast majority would be below 30 ppm as shown in EPA’s graph.

EPA also stated in this analysis: Under this scenario, most refineries with average sulfur levels 

higher than 10 ppm supply areas that are also supplied by refineries with sulfur levels at 10 ppm 

or below. We expect dilution of higher sulfur with lower sulfur in such areas to result in average 

sulfur levels no higher than about 20 ppm. Of those refineries projected to have average sulfur 

levels higher than 10 ppm under this scenario and which are the primary or only suppliers of 

gasoline to a particular area, none of the affected areas have historically been in nonattainment 

for ozone.

We agree with the above and believe this is a worst case scenario as it assumes perfect trading of 

sulfur credits, which is not realistic. Some of these higher sulfur refineries will not be able to rely 

on a supply of credits and therefore will take steps to reduce gasoline sulfur below the levels 

discussed above.

Commenter: Environmental Defense Fund (EDF)

EDF requests that EPA finalize a refinery gate sulfur cap of 20 ppm and a downstream sulfur cap 

of 25 ppm – standards that the Agency is officially requesting comment on. More lenient 

standards, as proposed by EPA, will not provide as robust health protections and “vehicles still 

have to be designed to operate on high sulfur fuel, and there will be less attention paid to limiting 

contamination downstream of the refinery gate.” 

EDF believes that the 20 ppm and 25 ppm standards will better protect human health. EPA has 

also stated that the tighter per gallon caps will benefit automakers by “limit[ing] the temporary 

exposure of vehicles in-use to sulfur levels that would significantly degrade their emission 

performance.” EPA also notes that the more protective caps would “serve to provide added 

assurance that all parts of the country would receive the full emission benefits of gasoline sulfur 

control.” 

EDF believes that the proposal gives refiners and affected downstream parties ample additional 

time and flexibilities to meet the more protective per-gallon caps and we urge the Agency to 

finalize the most protective refinery gate and downstream caps. 

In the event that EPA rejects the most protective 20 ppm refinery gate and 25 ppm downstream 

caps in favor of one of the two proposed alternatives, then EDF believes that EPA must opt for a 

50 ppm refinery gate cap and a 65 ppm downstream cap. In issuing the proposed Tier 3 rule, the 

Administrator found pursuant to Clean Air Act section 211(c)(1) that the emission products of 

higher-sulfur gasoline both: (1) cause or contribute to air pollution which may reasonably be 

anticipated to endanger public health or welfare; and (2) will impair to a significant degree the 

performance of any emissions control device or system which is either in general use or which 

the Administrator finds has been developed to a point where in a reasonable time it will be in 

general use were the fuel control to be adopted. In light of these findings and in order to “limit 

the temporary exposure of vehicles in-use to sulfur levels that would significantly degrade their 
Chapter 5: Tier 3 Fuel Sulfur Program

5-54

emission performance” and assure that “all parts of the country would receive the full emission 

benefits of gasoline sulfur control,” it would be arbitrary and capricious for EPA to set refinery 

gate and downstream caps that do not strengthen current standards. 

Commenter: Environmental Justice Leadership Forum on Climate Change

I caution that the credit trading provision designed to offer flexibility during the transition to 

more efficient vehicles and cleaner fuels seems counterintuitive to uniform national standards, 

thereby uniform benefits. I propose that the success of the Tier 2 standards are well documented 

and are all the transition that we ever needed.

We casually speak of trading credits, but if we look at the transaction closely, someone is 

standing with a basket full of credits, and someone is standing with a basket full of disbenefits or 

pollution.

Because all communities deserve their share of greenhouse gas reductions, fuel savings, energy 

security, mitigation of disproportionate adverse health impacts, economic growth, and job 

creation, I ask that you consider the benefits that – or the impact that the trading provision has 

had on the Tier 2 standards as we move forward in Tier 3.

Commenter: Marathon Petroleum Company LP (MPC)

-Regions served by just a few refineries could experience shortages of 25% - 50% during outages 

of gasoline sulfur reduction units at a 20 ppm cap, while outages would be minimized at sulfur 

caps exceeding 50 ppm. 

Commenter: Consumers Union (comment campaign)

EPA’s modeling indicates that regardless of the downstream sulfur cap selected between the two 

options being considered (95 ppm or 65 ppm), nearly all gasoline that ends up at the pump would 

be close to the 10 ppm average required of refineries. Automakers will provide insight into any 

burdens that a higher downstream cap may place on them to design vehicles that can tolerate the 

higher upper limit. Although sulfur-induced corrosion of catalytic converters is largely reversible 

if lower sulfur gasoline is used with regularity (justifying the averaging approach), if there are 

retail hot spots or regional high-sulfur clusters that consistently sell gasoline towards the upper 

limit, car owners in these areas may find their catalytic converters fail at a higher rate, and 

emissions may be significantly higher in such locales. 

Commenter: Natural Resources Defense Council (NRDC)

NRDC strongly supports the proposed requirement that refineries meet an annual average sulfur 

limit of 10 parts per million but EPA should tighten refinery gate and downstream sulfur caps. 

EPA Should Tighten Refinery Gate and Downstream Sulfur Caps. To help ensure that the 

maximize the cost-effective pollution reductions are achieved by the lower sulfur gasoline 
Tier 3 Summary and Analysis of Comments

5-55

coming from the refineries, EPA should lower the refinery gate cap to no more than 50 ppm by 

January 1, 2020 and the downstream cap to no more 65 ppm per gallon by March 1, 2020. 

Tightening the caps from today’s levels will help increase the certainty that gasoline’s low sulfur 

qualities will be maintained throughout the production and delivery processes. Tighter caps will 

reduce the probability of large sulfur spikes due to production equipment outages and 

maintenance and the probability of severe sulfur contamination during transport from the 

refinery gate to the retail outlets. By enhancing the quality assurance of delivered gasoline, 

automakers can better optimize the design of vehicle engines and exhaust systems within a 

smaller range of fuel specifications and the probability that all regions of the country will see the 

maximum pollution reductions from lower sulfur gasoline will be enhanced. 

Commenter: Northeast States for Coordinated Air Use Management (NESCAUM)

The current Tier 2 refinery gate and downstream caps of 80 and 95 ppm should be lowered to 50 

and 65 ppm, respectively. Given the stringency of the 10 ppm average standard, these lower caps 

will provide sufficient flexibility for refiners, pipelines, terminals, transmix processors, and 

gasoline additive manufacturers as achieved under the Tier 2 program, while ensuring maximum 

reduction in downstream sulfur levels. 

Long-term cap relief should not be made available in conjunction with lowering the sulfur caps 

below the current 80/95 ppm level. The other shorter term hardship relief options should be 

sufficient for all circumstances. Having noted that, it is important that refineries be given 

sufficient time so as not to be faced with the need to undergo two turnarounds (shutdowns and 

startups for major maintenance or equipment installation) in a relatively short time period. To the 

extent reasonable, the equipment installation for low sulfur fuel equipment should be 

accommodated during a normally scheduled maintenance turnaround. This avoids the excess 

emissions that occur during multiple shutdowns and startups of a refinery. 

Commenter: Union of Concerned Scientists (UCS)

EPA should lower the refinery gate and downstream per-gallon sulfur caps to 50 and 65 parts per 

million (ppm), respectively from the current levels of 80 ppm at the refinery gate and 95 ppm 

downstream. 

Reducing the sulfur content of gasoline is critical to achieving the public health and air quality 

benefits promised by the Tier 3 program. Combustion of sulfur in gasoline produces exhaust 

containing sulfur dioxide (SO2), which can cause respiratory ailments, particularly in sensitive 

populations like children, the elderly and people with asthma. Additionally, SO2 is a precursor to 

particulate matter formation; the detrimental effects of particulate matter on human health are 

discussed in the next section. Unlike other compounds, most notably NOx, sulfur compounds in 

vehicle exhaust cannot be converted into a less harmful molecule using emission control 

technologies like catalytic converters. Therefore, all tailpipe sulfur emissions are harmful and the 

only way to reduce sulfur emissions from the vehicle is to reduce its content in the fuel supply 

(5). 
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Sulfur in fuel also leads to sulfur oxides in the exhaust that poison the catalytic converter, 

reducing its effectiveness. Sulfur is adsorbed into the catalytic converter, greatly reducing the 

efficiency of the converter for cleaning up exhaust emissions such as NOx, carbon monoxide, 

and hydrocarbons. Therefore, reducing the sulfur content of gasoline will provide immediate 

public health benefits by increasing the performance of existing catalytic converters, reducing 

harmful emissions from the legacy fleet before complete fleet turnover has occurred. Moreover, 

as the nation’s vehicle fleet becomes more efficient, lower sulfur fuel will enable technology 

advances that allow greater efficiency gains, as well as ensure that existing technology performs 

as anticipated. Additionally, some technologies that help deliver efficiency improvements in the 

vehicle fleet can also lead to cooler exhaust temperatures, which inhibit the regenerative abilities 

of the catalytic converter, reducing its effectiveness. Lowering the sulfur content of fuel will 

ensure that we are able to effectively capitalize on the full suite of technologies available to 

improve both vehicle emissions and efficiency. 

5 - Testimony of Dr. Phil Blakeman of Johnson Matthey. Public hearing on Tier 3 Standards. 

Philadelphia, PA. April 24, 2013.

Our Response:

As discussed in Sections V.C.b and VII of the preamble to the final rule, our analysis for 

the Tier 3 final rule shows that a lower refinery gate cap would be unlikely to provide significant 

additional emission benefits. The emissions benefits associated with the Tier 3 program are 

mainly driven by the reduction in the average sulfur content of gasoline from 30 to 10 ppm, since 

vehicle emissions are proportional to the sulfur content of the fuel—changes in the cap would 

not affect this. In the context of the final ABT provisions, a higher cap does allow for increases 

in emissions on a temporal basis as one batch of fuel is allowed to have higher sulfur levels. 

However, this is then offset by reductions in emissions from batches of fuel that are then 

required to be below the 10 ppm average sulfur standard. Similarly, the ABT provisions allow 

for the possibility that the fuel from different refineries will cause varying emission reductions as 

one refinery’s higher average sulfur levels would lead to less emission reductions in-use. 

However, this is then offset by greater reductions in emissions due to the fuel produced by 

refineries with sulfur levels below the 10 ppm average standard.

We anticipate that in most cases refineries will make operational changes and/or 

investments in order to reduce their credit burden and reduce their compliance costs. Further, the 

10 ppm average standard by definition limits the amount of gasoline that can remain at higher 

sulfur levels (regardless of the cap). Thus, we anticipate that most refineries, including those 

using credits, will still average less than 20 or 30 ppm. Nevertheless, the final ABT program 

does allow for the possibility (regardless of the cap) that if higher sulfur fuel is concentrated in 

any certain geographical area, it would not receive the full emission reductions from the Tier 3 

program. We have considered the potential for areas to consistently receive fuel that might be 

predominantly higher than the 10 ppm average. However, since refineries generating credits and 

those using credits are interspersed across the country—and because most areas receive a 

considerable portion of their fuel by pipeline, barge, rail, or truck from refineries in other areas—

we expect the variation in average sulfur levels across the country to be too limited to warrant 

lowering the per-gallon cap to 50 ppm. Though, given the stringency of the 10 ppm average 

standard, we predict that in-use sulfur levels will generally be well below 50 ppm.
Tier 3 Summary and Analysis of Comments

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Thus, we believe it is best to retain the current Tier 2 80 ppm refinery gate cap, however 

we are committing to monitor and further evaluate in-use sulfur levels. As discussed above in 

Chapter 5.1.2.1, we will reassess the refinery gate sulfur cap level and the need for potential 

future regulatory action if it is warranted.

5.1.2.4. Downstream Cap Level Delta

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA’s RIA points out refiners (particularly smaller ones) may experience intermittent spikes in 

sulfur in gasoline secondary to cleaning tanks and other equipment or during turnarounds (46). 

However, options to dilute or otherwise reduce resultant higher sulfur content in this gasoline 

and related costs are not discussed. 

EPA also underscores that gasoline sulfur content can increase slightly from sulfur in additives, 

from contamination of the pipeline itself, and during pipeline transport transmix when the 

gasoline comes into contact with adjacent fuels such as jet fuel, that have very high sulfur 

content. Similar types of fuel supplier concerns raised in the Ultra-Low Sulfur Diesel 

rulemaking did not turn out to affect the ability to meet 15 ppm sulfur diesel requirements, 

despite use of the same domestic pipeline distribution systems. 

46 - RIA at 10-7. 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

Recommendations: Accordingly, the Association recommends – Retention of the 15 ppm 

differential between the refinery/import gate and the downstream sulfur cap to address sulfur 

contamination as gasoline moves through the lengthy distribution system; and 

Commenter: Kinder Morgan Transmix Company, LLC

We support EPA’s proposal to maintain a 15-ppm differential between the proposed refinery 

gate sulfur cap of 50-ppm and the proposed 65-ppm downstream sulfur cap. Our support of the 

15-ppm differential is based on gasoline sulfur data collected from our transmix processing 

facilities over a 3-year period of time. A reduction or elimination of the 15-ppm differential 

between the refinery gate cap and the downstream cap would have a significant impact on our 

operations which could result in facility shut-downs or limited operations. 

We also support EPA’s proposed downstream cap implementation date of 2020. We concur that 

based upon a 2017 refinery gate cap of 50-ppm, transmix processors would have sufficient time 

to evaluate the impact of the regulation on our operations prior to 2020. Transmix typically 
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consist of varying quantities of refined petroleum products such as gasoline, diesel fuel, aviation 

kerosene and home heating fuel. Reducing gasoline sulfur levels as presented in the proposed 

regulation; combined with the existing 15-ppm sulfur limit on ultra low sulfur diesel; may result 

in increasing sulfur levels in aviation kerosene or home heating fuel. Aviation kerosene and 

home heating fuel (where not restricted by state regulations) may contain sulfur levels up to 

3,000-ppm. The 2020 downstream implementation provides sufficient time to evaluate the 

impact of reducing gasoline sulfur levels on transmix and take corrective action if necessary. 

In summary: Yes, we support EPA’s proposal to maintain a 15-ppm differential between the 

proposed refinery gate sulfur cap of 50-ppm and the proposed 65-ppm downstream sulfur cap. 

Commenter: New York State Department of Environmental Conservation

New York’s fuel sampling program for 2011 and 212 shows no gasoline samples exceeding 

either of the existing per-gallon standards (over 8500 samples). The highest measured sulfur 

content was 79 ppm. There was no discernible difference between terminal samples and retail 

samples, suggesting that a 15 ppm downstream tolerance is larger than necessary. 

Our Response:

With regard to the downstream sulfur cap, we believe that maintaining a 15 ppm 

differential between the refinery gate sulfur cap and the downstream sulfur cap will provide 

pipeline operators, transmix processors, and gasoline additive users the same flexibility as was 

provided under the Tier 2 program. As was the case under the Tier 2 program, allowing a 15 

ppm differential is needed to ensure adequate flexibility in accommodating gasoline produced 

from transmix, instances of contamination during distribution, and for the use of necessary 

(sulfur-containing) additives. While we agree that sulfur levels of 95 ppm will not be the norm, 

in those rare circumstances when the sulfur contribution from all these sources are concurrently 

at their maximum levels, a very limited number of batches of gasoline at the 95 ppm downstream 

sulfur cap may be present in the distribution system. However, we do not expect that this will 

have a substantial impact on the average sulfur content of in-use gasoline.

Additionally, transmix processors must produce gasoline sufficiently below the 95 ppm 

downstream sulfur cap to accommodate any downstream sulfur increases from the use of 

gasoline additives and contamination from further distribution. The sulfur content of the 

gasoline produced by transmix processors is determined by the sulfur content of the transmix 

they receive, which is primarily a function of the sulfur content of gasoline and jet fuel 

components in the transmix. Transmix processors do not handle sufficient volumes to support 

the installation of desulfurization units, which would also increase the cost of the rulemaking 

with little to no additional emissions benefit.

Regarding comments that the 15 ppm delta is not needed because there were not 

contamination problems when the sulfur level in diesel fuel was reduced to 15 ppm, we note that 

the diesel program is quite different than the final gasoline sulfur program. During 

implementation of the diesel program, pipeline and downstream parties set “inlet specs” for the 

sulfur level of fuel that they would accept (some pipelines had inlet specs as low as 7 ppm). 
Tier 3 Summary and Analysis of Comments

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Thus, the diesel fuel that refiners needed to produce had to be much lower than the 15 ppm cap 

to ensure that the fuel would still meet a 15 ppm sulfur standard after traveling through the 

distribution system. Also, the diesel sulfur program was a phased-in program that also allowed 

for two month transition periods for when each level of the fuel production and distribution 

system was required to comply (e.g., refiners were required to comply by June 1, terminal 

operators by August 1, etc.); the Tier 3 gasoline program does not have a transition period. 

Lastly, contamination of 15 ppm diesel fuel was reduced by specific batch sequencing in 

pipeline; however, gasoline remains susceptible to contamination by higher sulfur jet fuel and 

heating oil.

5.1.2.5. Other (Alternate Phase-Down, SO2, etc.)

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

We also support reducing the refinery gate and retail pump per gallon caps to 20 and 25 ppm 

respectively for an interim time period, rather than leaving them at Tier 2 levels (80 and 95 ppm 

respectively), or partially reducing them to 50 and 65 ppm, respectively. In addition, we also 

advocate that as part of the Tier 3 rulemaking process, EPA should commit to a supplemental 

rulemaking to develop a pathway and timeline for reducing the retail cap for market gasoline 

sulfur to 10 ppm, consistent with other developed countries. This is important so that refineries 

can plan now for longer-term horizon of additional sulfur reduction, rather than seeing such 

changes as “moving the goal posts again.” It is also crucial to the product planning of Alliance 

and Global member companies that there is assurance that over time EPA is moving toward 

progressively lower sulfur standards at the retail pump toward a cap no greater than 10 ppm per 

gallon (45). 

Tier 3 sulfur reductions are also important because, if reduced to the lowest levels suggested by 

EPA (25 ppm retail cap), the sulfur level will come closer to harmonizing the 20 ppm retail cap 

in California and will create a predictable low sulfur standard nationwide. The results in the 

January 2013 Alliance North American Fuel Survey show that the average sulfur content of the 

samples outside of California was 25 ppm,65 or approximately three times higher than the 

California samples average of 7 ppm, so it should be feasible to transition to a lower national 

retail sulfur cap. 

In addition, it is important that the EPA include a pathway to continue to ratchet down the sulfur 

content of the per-gallon cap at the retail pump over time to reach a per-gallon retail pump level 

of 10 ppm, in order to optimize emission reductions. 

45 - We note that EPA’s own data shows that 5 ppm is even better for reducing emissions, as evidenced 

in its new study cited in the Preamble and RIA.

65 - The (octane) grade weighted (pool average for US (excluding California) would be closer to 27 ppm. 

Survey can be purchased from the Alliance website www.autoalliance.org.
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Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

We urge EPA to reduce the refinery gate and downstream caps to 20 and 25 ppm, respectively, 

perhaps with a slightly longer phase in period than the refinery average, and at the same time to 

develop a pathway toward a retail cap of 10 ppm per gallon. Effective standards should be put in 

place for Tier 3, and the Agency can then provide ad hoc relief, with a notice and comment 

process, for refiners and downstream distributors that can show evidence or reasons they actually 

need it. 

Because the country as a whole is already trending toward lower sulfur levels, EPA can and 

should finalize the means to transition to a retail cap of 25 ppm, and then plan a pathway to reach 

an ultimate goal of 10 ppm retail cap over the next 12-15 years. If it turns out that this goal 

cannot be accomplished, then EPA can modify the limit, or extend the deadline, but the policy to 

ultimately minimize retail gasoline sulfur to a 10 ppm cap per gallon (and reduce sulfur content 

of other pipeline products mingled or trans-mixed with gasoline accordingly) should be 

developed now, for implementation within the framework of Tier 3 authority. 

Commenter: Consumers Union

EPA should consider issuing a prospective reporting or data collection requirement that could 

help it identify whether such hot spots emerge and whether they warrant a lower downstream 

sulfur cap in the future. 

Commenter: General Motors LLC (GM)

In addition, is important that the EPA include a pathway to continue to ratchet down the sulfur 

content of the per-gallon cap at the retail pump over time to reach a per-gallon retail pump level 

of 10 ppm, in order to optimize emission reductions. 

The Tier 3 rulemaking is the correct place to set the near-term standards for sulfur and also 

create a roadmap of how the agency will further reduce sulfur in the coming years. 

Commenter: Consumers Union (comment campaign)

EPA should consider issuing a prospective reporting or data collection requirement that could 

help it identify whether such hot spots emerge and whether they warrant a lower downstream 

sulfur cap in the future. 

Commenter: Ozone Transport Commission (OTC)

In addition to proposing an average gasoline sulfur concentration of 10 ppm, EPA proposed 

maintaining downstream and refinery caps of 95 ppm and 80 ppm, respectively. This was done 

to allow refineries to have the flexibility to economically meet the sulfur requirements through 
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an allowance, banking, and trading (ABT) program. EPA also suggested the possibility of lower 

downstream and refinery caps and requested comment on these lower caps.

OTC suggests that EPA consider evaluating a gradual reduction in the sulfur caps from 2017-

2025. The caps would begin at 95 and 80 ppm respectively for the downstream and refinery 

levels, then be reduced to 65 and 50 ppm by 2020, and finally, in 2025, be reduced to a level that 

harmonizes the sulfur cap nationally. This approach could still allow refineries to have the 

economic flexibility that they need to successfully meet the caps at a low cost, while, in the long 

term, limiting anomalies in the fuel market that could result in particular areas having fuels that 

do not reduce NOx to a level necessary to reduce ambient ozone concentrations to attainment 

status concentrations. 

Commenter: Pennsylvania Department of Environmental Protection (DEP)

The EPA should allow the current 80 ppm fuel sulfur level refinery gate cap and the 95 ppm 

downstream per gallon cap. The agency should consult with the refinery industry, especially 

small refiners, and develop a phase-in schedule that will lower refinery gate and downstream 

caps to the 20 ppm to 30 ppm range by 2025. 

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA’s RIA points out refiners (particularly smaller ones) may experience intermittent spikes in 

sulfur in gasoline secondary to cleaning tanks and other equipment or during turnarounds (46). 

However, options to dilute or otherwise reduce resultant higher sulfur content in this gasoline 

and related costs are not discussed. 

EPA also underscores that gasoline sulfur content can increase slightly from sulfur in additives, 

from contamination of the pipeline itself, and during pipeline transport transmix when the 

gasoline comes into contact with adjacent fuels such as jet fuel, that have very high sulfur 

content. If, as the Tier 3 RIA indicates, the increase in the per gallon cap at retail from the per 

gallon refinery gate cap is due to the sulfur content of other current products moving through the 

pipeline, rather than older sulfur deposits within the pipeline itself, then one potential solution for 

gasoline sulfur retail cap limits is to reduce the sulfur content of these other products, which 

could have environmental benefits as well. If jet fuel can be as high as 2-3000 ppm sulfur, and 

low sulfur fuel oil can be as high as 500 ppm, then EPA should lead efforts to reduce that content 

and find substitute means for the lubricity loss from reduced sulfur. 

46 - RIA at 10-7.

Our Response:

As noted above in Chapter 5.1.2.1, we are committing to monitor and further evaluate inuse sulfur levels and their impact on vehicle emissions and, if it is warranted, we will reassess 

the sulfur cap level and the need for potential future regulatory action. This evaluation will 

include analyses of in-use fuel surveys, refinery batch data, and the sulfur credit market. We will 
Chapter 5: Tier 3 Fuel Sulfur Program

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also evaluate any issues or concerns that might arise during the implementing the program. 

Finally, we will also carry out an ongoing evaluation of data submitted by the vehicle 

manufacturers on the performance of their Tier 3 vehicles in-use.

5.1.3. Additives

What Commenters Said:

Commenter: Automotive Aftermarket Industry Association (AAIA)

The Automotive Aftermarket Industry Association (AAIA) appreciates this opportunity to 

provide comments on the proposed Tier 3 Emissions and Fuel Standards for motor vehicles. In 

particular, we would like to address the provision relating to sulfur content of automotive fuel 

additives. 

AAIA supports the provision within the Tier 3 standards that proposes ‘gasoline additives that 

are used downstream of the refinery at less than 1 volume percent must limit the sulfur 

contribution to the finished gasoline from the use of their additive to less than 3 ppm when the 

additive is used at the maximum recommended treatment rate.’ At currently recommended use 

levels, aftermarket fuel additives contribute less than the proposed 3 ppm. Furthermore, additives 

are not applied every time a motor vehicle stops for a fill-up. Therefore, the sulfur contribution 

continues to decrease over time. 

Commenter: Consumer Specialty Products Association (CSPA) & Automotive Specialty 

Products Alliance (ASPA)

Our organizations support the proposed rule as it pertains to the sulfur content of downstream 

additives used at less than 1.0 percent by volume of the resultant additive(s)/fuel mixture 

(Section A (3): Per-Gallon Sulfur Caps). When used at the maximum recommended treatment 

rate, aftermarket gasoline additives contribute less than the proposed limit of 3 parts per million 

sulfur to the finished gasoline. Considering most of these products are recommended for use 

every 3,000-10,000 miles, the overall net increase in sulfur levels is further diluted. 

Manufacturers of aftermarket gasoline additives have taken many proactive steps to protect the 

environment, including adopting sustainable packaging initiatives – moving, where possible, to 

more concentrated packages, which require using less solvent, less packaging and therefore 

creating less freight. Additionally, aftermarket additives play an important role in the cleanup of 

intake valves, fuel injectors and combustion chambers, resulting in fuel economy savings and 

emissions reductions. 

Commenter: Motor & Equipment Manufacturers Association (MEMA)

Control of fuel sulfur content is a critical aspect of Tier 3. Specifically for additives, MEMA 

agrees with the proposed treatment of sulfur content in downstream additives that are used at less 

than one percent (1.0%) by volume of the resultant additive/fuel mixture. When used at the 
Tier 3 Summary and Analysis of Comments

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maximum recommended treatment rate, aftermarket gasoline additives contribute less than the 

proposed limit of three (3) parts-per-million sulfur to the finished gasoline. Since many of these 

products are recommended for use every 3,000 to 10,000 miles, the overall net increase in sulfur 

levels is further diluted. For downstream additive manufacturers, the proposed recordkeeping 

requirements demonstrating compliance is reasonable and manageable. 

Commenter: New York State Department of Environmental Conservation

Control of the sulfur content of gasoline additives is necessary. The proposed sulfur limits are 

low enough that the sulfur content of fuel additives can have a material impact on the finished 

gasoline sulfur content, and therefore the environmental performance. We support EPA’s 

proposal to indirectly control the sulfur content of these additives by limiting the increase from 

an additive (at its maximum treat rate) to 3 ppm. We also encourage EPA to promulgate limits on 

the combined sulfur contribution for all additives blended into a batch of gasoline, not just for 

each individual additive. 

We also support EPA’s requirement that any blender blending an additive at a rate of 1.0 percent 

by volume or higher comply with the gasoline sulfur requirements applicable to refineries. 

Our Response:

The Tier 3 FRM finalizes the requirement that manufacturers of gasoline additives used 

downstream of the refinery at less than 1 volume percent must limit the sulfur contribution to the 

finished gasoline from the use of their additive to no more than 3 ppm when the additive is used 

at the maximum recommended treatment rate. The additive manufacturer will be required to 

maintain records of its additive production quality control activities which demonstrate that the 

sulfur content of additive production batches is such that when the additive is used at its 

maximum recommended treatment rate it will add no more than 3 ppm to sulfur content of the 

finished gasoline.

These requirements are designed to prevent the potential dumping of high sulfur 

materials into gasoline under the guise of the addition of gasoline additives. We continue to 

believe that all current gasoline additives contribute less than 3 ppm to the sulfur content of the 

finished fuel when used at the maximum recommended treatment rate (with 3 ppm being the 

extreme). Normal additive production quality control practices already have had to consider the 

sulfur contribution of the additive to finished gasoline as a result of the Tier 2 gasoline sulfur 

requirements. The maximum recommended treatment rate is already stated on product transfer 

document or packaging for the additive. Therefore, the Tier 3 requirements for gasoline 

additives will not constrain the use of genuine gasoline additives or result in significant 

additional costs to gasoline additive manufacturers. Parties that introduce additives to gasoline at 

over 1.0 volume percent are required to satisfy all of the obligations of a refiner and fuel 

manufacturer including demonstration that the finished blend meets the applicable sulfur

specification.

We believe that additional controls to limit the combined sulfur contribution for all 

additives blended into a batch of gasoline in addition to controlling the sulfur contribution from 
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individual additives are not necessary at this time, would add an unwarranted additional 

compliance burden, and could interfere with the use of necessary downstream additives. Certain 

additives that provide critical fuel performance characteristics (e.g., corrosion control, 

demulsifiers) contain sulfur-containing compounds as an essential functional component. Such 

additives are used to remedy specific instances of gasoline quality problems, and their treatment 

rate is governed by the desire to limit the added cost from their use.

5.1.4. Leadtime

5.1.4.1. Environmental Benefit of 2017 Start Date

What Commenters Said:

Commenter: Advanced Engine Systems Institute (AESI)

Unfortunately, as occurred during the debate on EPA’s Tier 2 regulations, the petroleum industry 

is again opposing new requirements to reduce sulfur in transportation fuels. This is happening 

despite the significant pollution reduction benefits that would be achieved immediately from the 

use of lower sulfur fuel by the existing Tier 2 fleet, and those benefits that would result from 

phasing in Tier 3 starting in model year 2017.

Commenter: Union of Concerned Scientists (UCS)

We concur with EPA’s assessment that these lower levels are achievable and support the 

timelines that EPA has outlined. 

Our Response:

As discussed in more detail in Section III of the preamble to the final rule, the Tier 3 

program will significantly reduce emissions of VOC, NOX (including NO2), direct PM2.5, CO, SO2, 

and air toxics nationwide, with immediate benefits due to the reduction in gasoline sulfur content 

from 30 to 10 ppm starting in 2017. The 10 ppm sulfur standard will provide significant 

reductions in harmful emissions independent of the vehicle standards and these reductions are 

significant and contribute to the total monetized health benefits. The vehicle standards will also begin 

to reduce emissions as the cleaner cars and trucks begin to enter the fleet in model year 2017 and 

model year 2018, respectively. The magnitude of reduction will grow as more Tier 3 vehicles enter 

the fleet. These reductions will help state and local agencies in their effort to attain and maintain 

health-based NAAQS “as expeditiously as practicable.” (Sections 172(a)(2) and 181 of the 

CAA). The Tier 3 emissions reductions and air quality improvements occur in a timeframe that 

is relevant for 2008 ozone nonattainment areas classified as moderate, serious, severe and 

extreme, and beginning the program in 2017 is specifically relevant for attainment of the 

NAAQS for moderate areas in 2018. Without the Tier 3 program, some areas would have to 

adopt other, less cost-effective measures to reduce emissions from other sources under their state 

or local authority. In the absence of additional controls, many areas would continue to have 

ambient ozone concentrations exceeding the NAAQS in the future. Further, by 2030, the Tier 3 
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gasoline sulfur and vehicle emission standards will result in emissions reductions of 21 percent 

for NOx and VOC emissions from on-highway vehicles, and 24 percent for CO emissions. 

National emissions of many air toxics from on-highway vehicles will also be reduced by 10 to 

nearly 30 percent.

5.1.4.2. Vehicle Need for 2017 Start Date

We received comments in support of and against our January 1, 2017 compliance date. 

Commenters that opposed this date argued that it was not needed in light of the implementation 

dates for vehicle standards. Commenters in support argued that it had to be synchronized with 

the 2017 compliance date for certain light duty vehicles.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

Implementation on January 1, 2017 is not necessary to enabling heavy duty vehicles to meet the 

emission standards, for the development of lower cost technologies to improve fuel economy; or 

to reduce emissions from the in-use vehicle fleet. 

In the proposal, EPA asserts that reducing the sulfur content of gasoline to 10 ppm has three 

primary benefits: a) enabling heavy duty vehicles to meet NMOG and NOx standards throughout 

their useful life; b) enabling the development of lower cost technologies to improve fuel 

economy; and, c) reducing emissions from the in-use vehicle fleet. Each of these claims are 

discussed below. None of these claimed benefits justify a January 1, 2017 effective date for the 

10 ppm gasoline sulfur standard. 

EPA asserts that lowering gasoline sulfur to 10 ppm is necessary to enable larger vehicles and 

trucks to reduce the NMOG+NOx low enough to comply with the 30 mg/mi fleet-average 

standard vehicle emission standards over the useful life of the vehicles. Even if reducing gasoline 

sulfur to 10 ppm does help such vehicles comply with the standard over their useful life, as 

EPA’s own proposal makes clear, that does not justify January 1, 2017 implementation. The 

vehicle standards for vehicles and trucks exceeding 6000 lbs. GVWR is not even effective until 

the 2018 model year. Thus, clearly, January 1, 2017 implementation is not necessary. 

EPA proposes to allow vehicle manufacturers to generate early federal credits against the current 

Tier 2 Bin 5 requirement in MYs 2015 and 2016 for vehicles under 6,000 lbs. GVWR and MYs 

2016 and 2017 for vehicles greater than 6,000 lbs. GVWR. These early federal credits can be 

used without limitation for MY 2017. In other words, the vehicles are not required to meet the 

Tier 3 vehicle emission standards at the start of the program. See 78 Federal Register 29867-68. 

As such, it is clearly not necessary to reduce the gasoline sulfur level to 10 ppm on January 1, 

2017. 
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Numerous other provisions of the proposed rule support the conclusion that implementation on 

January 1, 2017 is not necessary. In particular, the provisions for generation of early credits for 

compliance with the vehicle standards, the schedule for phase in of the vehicle standards, the 

small refiner/refinery exemption until 2020, the per-gallon gasoline sulfur cap, and the early 

credit program for the gasoline sulfur program all demonstrate that EPA is unnecessarily rushing 

implementation of this rule by proposing a January 1, 2017 implementation. Furthermore, 

because the impact of sulfur on vehicle catalysts is reversible, providing more lead time will not 

prevent vehicles from meeting the vehicle emission standards over their useful life. Each of these 

issues is discussed below. 

In addition to the ability to delay implementation of the vehicle standards through the generation 

of early credits, the program for vehicle manufacturers also contains phase-in schedules that 

make clear that it is not necessary to implement the 10 ppm gasoline sulfur requirement on 

January 1, 2017. As noted above, EPA maintains that reducing gasoline sulfur to 10 ppm is 

necessary to help heavy duty vehicles meet the NMOG + NOx standards over their useful life. 

Even if that is true, as noted above, the vehicles standards do not even apply to vehicles above 

6000 lbs. GVWR until MY 2018. Moreover, EPA is considering not even requiring vehicle 

manufactures to meet the standards until MY 2019. See 78 Federal Register 29876. 

Commenter: Johnson Matthey

Adoption of this part of the Tier 3 proposal would bring the U.S. in line with Europe and Japan, 

who already have these low sulfur gasoline limits, and places like China who have committed to 

bringing in low sulfur gasoline by the end of 2017.

Commenter: Marathon Petroleum Company LP (MPC)

In the proposal, EPA asserts that reducing the sulfur content of gasoline to 10 ppm has three 

primary benefits: a) enabling heavy duty vehicles to meet NMOG and NOx standards throughout 

their useful life; b) enabling the development of lower cost technologies to improve fuel 

economy; and, c) reducing emissions from the in-use vehicle fleet. Each of these claims are 

discussed below. None of these claimed benefits justify a January 1, 2017 effective date for the 

10 ppm gasoline sulfur standard. 

EPA asserts that lowering gasoline sulfur to 10 ppm is necessary to enable larger vehicles and 

trucks to reduce the NMOG+NOx low enough to comply with the 30 mg/mi fleet-average 

standard vehicle emission standards over the useful life of the vehicles. Even if reducing gasoline 

sulfur to 10 ppm does help such vehicles comply with the standard over their useful life, as 

EPA’s own proposal makes clear, that does not justify January 1, 2017 implementation. The 

vehicle standards for vehicles and trucks exceeding 6000 lbs GVWR is not even effective until 

the 2018 model year. Thus, clearly, January 1, 2017 implementation is not necessary. 

Numerous other provisions of the proposed rule support the conclusion that implementation on 

January 1, 2017 is not necessary. In particular, the provisions for generation of early credits for 

compliance with the vehicle standards, the schedule for phase in of the vehicle standards, the 

small refiner/refinery exemption until 2020, the per-gallon gasoline sulfur cap, and the early 
Tier 3 Summary and Analysis of Comments

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credit program for the gasoline sulfur program all demonstrate that EPA is unnecessarily rushing 

implementation of this rule by proposing a January 1, 2017 implementation. Furthermore, 

because the impact of sulfur on vehicle catalysts is reversible, providing more lead time will not 

prevent vehicles from meeting the vehicle emission standards over their useful life. Each of these 

issues is discussed below. 

In addition to the ability to delay implementation of the vehicle standards through the generation 

of early credits, the program for vehicle manufacturers also contains phase-in schedules that 

make clear that it is not necessary to implement the 10 ppm gasoline sulfur requirement on 

January 1, 2017. As noted above, EPA maintains that reducing gasoline sulfur to 10 ppm is 

necessary to help heavy duty vehicles meet the NMOG + NOx standards over their useful life. 

Even if that is true, as noted above, the vehicles standards do not even apply to vehicles above 

6000 lbs GVWR until MY 2018. Moreover, EPA is considering not even requiring vehicle 

manufactures to meet the standards until MY 2019. See 78 Federal Register 29876. 

EPA proposes to allow vehicle manufacturers to generate early federal credits against the current 

Tier 2 Bin 5 requirement in MYs 2015 and 2016 for vehicles under 6,000 lbs GVWR and MYs 

2016 and 2017 for vehicles greater than 6,000 lbs GVWR. These early federal credits can be 

used without limitation for MY 2017. In other words, the vehicles are not required to meet the 

Tier 3 vehicle emission standards at the start of the program. See 78 Federal Register 29867-68. 

As such, it is clearly not necessary to reduce the gasoline sulfur level to 10 ppm on January 1, 

2017. 

Numerous aspects of the proposed gasoline sulfur rule make clear that January 1, 2017 

implementation is not necessary to enable vehicles to meet the emission standards and that EPA 

is unnecessarily rushing implementation of the rule. 

Although EPA proposes to make the 10 ppm gasoline sulfur standard generally effective January 

1, 2017, EPA proposes to allow small refiners and small refineries to continue to produce 

gasoline under the existing Tier 2 rules – i.e., 30 ppm annual average standard/80 ppm per-gallon 

cap – until January 1, 2020. 

Similarly, EPA proposes to maintain the existing Tier 2 per-gallon cap of 80 ppm, under the Tier 

3 rules, at least until 2020. This too demonstrates that EPA does not believe that January 1, 2017 

implementation of the 10 ppm sulfur standard is necessary for vehicles to meet the Tier 3 

standards. 

The early credit provisions under the gasoline sulfur program demonstrate the same thing. As 

EPA explains in the proposal, the effect of the early credit program is to delay the 

implementation of the 10 ppm annual average standard. We believe the early credit provision is 

an important part of the proposal and we support it. However, it does demonstrate that January 1, 

2017 of the 10 ppm sulfur standard is not necessary for vehicles to meet the Tier 3 standards. 

In all of the above situations, EPA places no restrictions on the use of such Tier 2 gasoline to 

prohibit its use in newer vehicles that are required to comply with the new vehicle standards, 

demonstrating that January 1, 2017 implementation is not necessary. 
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As explained above, January 1, 2017 implementation of the 10 ppm gasoline sulfur requirement 

is not necessary to enable vehicles to meet the NMOG + NOx standards. But, even if it is true as 

EPA claims that sulfur will negatively impact catalyst performance on such vehicles, that does 

not justify the January 1, 2017 implementation date, because the effect of sulfur on catalysts is 

reversible. A new study (described in detail in Section II.B of these comments) demonstrates that 

exposure to gasoline fuels containing sulfur levels of 80 ppm sulfur has no lasting impact on the 

performance of exhaust emission control systems on modern vehicles operated on 10 ppm sulfur 

gasoline.

Commenter: New York State Department of Environmental Conservation

The 2017 gasoline sulfur compliance date for most refineries must not be delayed. 

Significant immediate benefits accrue when the gasoline sulfur content is reduced, as sulfur 

catalyst poisoning of existing catalytic converters is (at least partly) reversed. Although any large 

chemical process construction project is a substantial undertaking, the processes and equipment 

necessary to produce low sulfur gasoline are well known. Tier 3 has been under active 

discussion, with petroleum industry participation, for several years. 

Commenter: Shell Oil Products for Shell and Motiva

Furthermore, as explained in more detail in the API/AFPM comments, a January 1, 2017 

implementation date is not necessary to achieve EPA’s stated objectives. EPA asserts that the 

lower sulfur levels are necessary to help heavy duty vehicles meet the vehicle emission standards 

over their useful life, yet those vehicle standards are not even effective until the 2018 model 

year, and various other provisions from the phase-in of the vehicle standards to the small 

refiner/refinery exemption demonstrate that the January 1, 2017 implementation date is not 

necessary. 

Commenter: Sierra Club, Clean Air Watch, Respiratory Health Association

Tier 3 Standards complement existing vehicle standards: Finalizing the proposed Tier 3 

standards by December 31, 2013 is critical to ensuring that existing vehicle standards are fully 

implemented. Automakers are innovating and employing advanced vehicle technologies needed 

to meet the historic light-duty vehicle efficiency standards that will increase fleet efficiency to an 

average of 54.5 miles per gallon by 2025. In order to fully utilize advanced vehicle technologies, 

automakers need lower-sulfur gasoline. 

For lower-sulfur gasoline to reach the market in 2017, in time to synchronize with the 2017-2025 

light-duty vehicle efficiency standards, the proposed Tier 3 standards must be finalized no later 

than December 31, 2013. 

Our Response:
Tier 3 Summary and Analysis of Comments

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We disagree with the comments that the January 1, 2017 start date is not necessary given 

that the heavy duty emissions standards are effective with the 2018 model year. We also 

disagree with the commenters that argue that the phase-in schedule and flexibilities seem to 

suggest that there is no need for the gasoline sulfur standards to begin in 2017. As explained in 

Section IV of the preamble to the Tier 3 final rule, vehicle standards begin to phase in for 

vehicles less than 6000lbs GWVR with the 2017 model year. As also explained in Section IV of 

the preamble to the final rule, such vehicle manufacturers may comply with today’s standards by 

using early credits but that does not mean they are not required to meet the standards in 2017. 

Thus, we expect that the vehicle standards will begin to reduce emissions as the cleaner cars the 

fleet in model year 2017. As also previously discussed, immediate benefits will result in 2017, as 

the average sulfur standard of 10 ppm will facilitate emission reductions from vehicles that are 

on the road today. Thus, as explained in Section III of the preamble, and as some of the 

commenters correctly noted, the Tier 3 sulfur standards will reduce emissions from the on-road fleet 

immediately upon implementation in calendar year 2017.

We also disagree with the comments that the January 1, 2017 implementation date is 

unnecessary given that sulfur impacts on catalyst is reversible. As discussed in more detail in 

Chapter 4.1.4.3 of this document and as explained in Section IV.A.6 of the preamble, operating a 

catalyst at a sufficiently high temperature under net reducing conditions (e.g., air-to-fuel equivalence 

that is net fuel-rich of stoichiometry) can effectively release the sulfur oxides from the catalyst 

components. Thus, regular operation at sufficiently high temperatures at rich air-to-fuel ratios can 

minimize the effects of fuel sulfur levels on catalyst active materials and catalyst efficiency. It 

cannot, however, completely eliminate the effects of sulfur poisoning. In current vehicles, 

desulfurization conditions occur typically at high loads when there is a degree of commanded 

enrichment (i.e., fuel enrichment commanded by the engine management system primarily for 

protection of engine and/or exhaust system components). A study of Tier 2 vehicles in the in-use 

fleet recently completed by EPA shows that emission levels immediately following high speed/load 

operation is still a function of fuel sulfur level, suggesting that lower gasoline sulfur levels will bring 

emission benefits unachievable by catalyst desulfurization procedures alone. For example, if a 

vehicle operates on gasoline with less than 10 ppm sulfur, exhaust emissions stabilize over repeat 

FTP tests at emissions near those of the first FTP that follows the high speed/load operation and 

catalyst desulfurization. Therefore, continued operation on gasoline with 10 ppm average sulfur 

content or lower is necessary after catalyst desulfurization in order to achieve emissions reductions 

with the current in-use fleet. We also explained that to the extent such conditions do not occur 

today as part of normal driving for vehicles in the in-use fleet, there is no practical way to 

modify such existing vehicles to do so. Thus, reducing fuel sulfur levels has been the primary 

regulatory mechanism to minimize sulfur contamination of the catalyst and ensure optimum 

emissions performance over the useful life of a vehicle and is the only effective means for the inuse fleet. 

For Tier 3 vehicles, there are several reasons why regular operation at the high exhaust 

temperatures and rich air-to-fuel ratios necessary for catalyst desulfurization is not desirable and may 

not be possible. The temperatures necessary to release sulfur oxides are high enough to lead to 

thermal degradation of the catalyst over time through thermal sintering of active materials. Sintering 

reduces the surface area available to participate in reactions. Additionally, it is not always possible to 

maintain these catalyst temperatures (because of cold weather, idle conditions, light load operation). 

Also, the air-to-fuel ratios necessary for sulfur removal can result in increased PM, NMOG and CO 

emissions.
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While the fuel ABT provisions and small refiner/small volume refinery provisions 

already allow this to some degree – in order to provide a smooth phase-in of the 10 ppm average 

sulfur standard – delaying the standard would exacerbate this further. Since, as discussed in 

Section V.L of the preamble to the final rule, we believe there is sufficient lead time provided to 

refiners, there seems to be no reason to delay implementation of the fuel standards further.

The Tier 3 light-duty vehicle emissions standards will phase in beginning with model 

year (MY) 2017. This will enable auto manufacturers to be able to design a 50-state fleet of 

vehicles as a 2017 start date will harmonize the Federal standards with the California LEV III 

program. Further, we also have designed the Tier 3 program to be implemented in the same 

timeframe as the GHG emissions and fuel economy standards for model years 2017-2025. The 

2017 start date of the Tier 3 program addresses interactions with the 2017 LD GHG rule in a 

manner that aligns implementation of the two programs, to achieve significant criteria pollutant 

and GHG emissions reductions while providing regulatory certainty and compliance efficiency. 

Thus, vehicle manufacturers will be able to design new vehicle platforms for compliance with 

both the GHG and Tier 3 standards at the same time.

Delaying the program to 2018 would not only negate the benefits of harmonizing with 

LEV III and the LD GHG program, it would also delay important health benefits that come from 

the systems approach of beginning the Tier 3 vehicle and fuel standards in tandem. The vehicle 

and fuel ABT programs, small refiner/small refinery provisions, and vehicle phase-in allow for 

the Tier 3 program to begin in 2017, while offering manufacturers and refiners the ability to 

spread out their compliance costs in the manner that best works for their specific situations.

5.1.4.3. Refinery Lead Time

5.1.4.3.1. Overall Lead Time Required 

What Commenters Said:

Commenter: American Fuel & Petrochemical Manufacturers (AFPM)

Organization Type: Fuels Industry

We believe that there should be at least five years between the promulgation of a Tier 3 rule that 

includes reduction in the sulfur content, gasoline, and its effective date. Refiners need this lead 

time to schedule equipment modifications or the installation of new equipment during a 

turnaround. Otherwise refiners may be temporarily shut down with the associated supply 

impacts.

Tier 3 is not required by law, and the selection of 2017 is arbitrary. If the EPA promulgates a 

reduction in the sulfur content of gasoline in late 2013, then the effective date should not be 

earlier than 2019. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 
Tier 3 Summary and Analysis of Comments

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Manufacturers (AFPM)

Rather than the 3 years EPA proposes, if EPA decides to proceed with the Tier 3 rulemaking, 

EPA should provide 5 years of lead time from the date of publication of the final rule in the 

federal register in order to implement any changes to the average gasoline sulfur requirement. 

Five year lead time from publication of Final Rule is required for implementation.

EPA asserts that 3 years of lead time is more than sufficient for the petroleum industry to 

implement the 10 ppm gasoline sulfur requirement. 78 Federal Register 29923. We disagree. 

EPA needs to provide 5 years of lead time. As discussed above, rushing implementation of the 

gasoline sulfur requirement is not necessary. Rushing implementation will unnecessarily raise 

the cost to implement the program. Rushing implementation undermines the ability of the 

industry to adequately plan projects, secure contractors and equipment at competitive rates, 

optimize solutions, and align construction projects with existing maintenance turn-around 

schedules. In addition, air permits will be necessary at many refineries, and EPA has been 

challenged in issuing permits in a timely fashion (as is discussed in further detail in section VII.F 

of these comments.) All of these factors will tend to increase compliance costs. 

In the proposal, EPA puts forth Table V-3 with a timeline that the Agency believes illustrates the 

time needed to implement the 10 ppm gasoline sulfur requirement at a refinery. 78 Federal 

Register 29925. We disagree with EPA’s suggested timeline. We believe that a more accurate 

amount of time needed to implement major new rules like the 10 ppm gasoline sulfur 

requirement is at least five years. The Tier 2 rules were finalized in February 2000, with 

compliance required to phase in from 2004-06 (with compliance flexibilities that had a more 

meaningful impact, as discussed below). Ultra Low Sulfur Diesel (ULSD) rules were finalized in 

January 2001; with a compliance phase-in period requiring that 15 ppm sulfur diesel constitute 

80% of the highway pool in mid-2006. Compliance lead times need to be longer than these two 

significant rulemakings to reduce sulfur because of new GHG requirements at refiners, and the 

increased reliability of refining equipment has extended refinery turn-around time to 

approximately 5 years. These recent changes for refiners add complexities that warrant 

additional Tier 3 compliance lead time. 

In the proposal, EPA suggests that 3 years of lead time is feasible, in part, because EPA began

talking to refiners about the possibility of regulating gasoline sulfur a couple of years ago. This is 

inappropriate because EPA decisions concerning key aspects of this rule are not yet final. EPA 

understands that there can be many changes made from the time a rule is proposed until it is 

finalized in response to comments submitted by the public, and that therefore there is too much 

uncertainty to make detailed implementation plans until the final rule is issued. In this case, for 

example, we do not yet know whether EPA will actually require a reduction in gasoline sulfur 

given the high costs and de minimis environmental benefits, we do not know when the rule will 

be effective, we do not know whether EPA will leave the per-gallon cap at 80 ppm, etc. 

EPA’s three-year lead time is grossly inadequate. Six years is workable. Five years is the 

absolute minimum. Three years is insufficient to ensure against market disruptions. Refiners are 

able to operate for about five years between turnarounds, which is the most efficient time to 
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make major changes. A three-year lead time means that normal maintenance schedules are 

likely to be disrupted, potentially impacting gasoline supply and increasing the overall cost.

Commenter: BP Products North America Inc.

Achieving the proposed January 1, 2017 effective date raises major concerns across BP. The 

availability of sufficient sulfur credits under the proposed Averaging, Banking and Trading 

program also raises major concerns. Even the availability of credits from 2014 will not be known 

until early 2015, less than 2 years from EPA’s proposed effective date. Completing the necessary 

engineering, permitting, procurement, construction and startup by January 1, 2017 is highly 

unlikely. Pursuing completion of the investments on a compressed schedule also leads to 

increased costs. In order to complete the necessary investments and minimize unnecessary costs, 

BP proposes that EPA provide five years of lead time from the date the final rule is published. 

BP also agrees with API and AFPM’s conclusion that the 10 ppm annual average gasoline sulfur 

standard is not necessary on January 1, 2017 as asserted by EPA.

Commenter: Chevron Products Company

We are opposed to the implementation schedule proposed by the EPA. The 2017 compliance 

deadline does not provide sufficient time to make necessary refinery modifications and would 

significantly increase the cost of the required upgrades. If the agency proceeds with the gasoline 

sulfur reduction requirement, the program start date should be no sooner than five years after the 

date of the final regulation. 

We do not agree with the program start date of January 1, 2017 as this date only provides 3 years 

for implementation, assuming the rule is finalized by the end of 2013. This is insufficient for a 

refinery that is required to invest and chooses to do so by the start of the program. By 

comparison, the Tier 2 program was finalized in 1999, with implementation phased in from 2004 

to 2006. The Tier 3 program start date should be extended to allow a minimum of five years for 

implementation. We would propose a start date of January 1, 2019, assuming that the Tier 3 

regulations are finalized by January 1, 2014. 

We agree that the technology for sulfur reduction to the 10 ppm level is available and has been 

demonstrated at certain refineries in operation today. However, we believe that EPA has 

underestimated the cost and complexity of the changes which will be required in the refining 

industry to achieve this reduction. 

The time required for permitting is becoming longer due to local regulations and GHG programs. 

We do not agree that the analysis of permit times should be limited to the estimates provided by 

OAQPS. We are seeing other government agencies placing additional requirements on refinery 

permits for a variety of GHG, safety, and environmental concerns, all of which increase the time 

required to obtain a permit. California refineries producing gasoline subject to the Tier 3 

regulations may encounter even longer permitting times and increased scrutiny, taking them well 

beyond the proposed implementation period. 

Commenter: ExxonMobil
Tier 3 Summary and Analysis of Comments

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If the Agency decides to proceed with this rulemaking, we recommend that EPA provide a five 

year lead time from the publication date of the final rule in the Federal Register before 

implementation of a new fuel standard; 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

The Association recognizes that EPA is proposing to require a significant reduction in the sulfur 

content of gasoline, beginning in 2017, as part of a systems approach to addressing the impacts 

of motor vehicles and fuels on air quality and public health. However, Members have concerns 

that the proposed rule is very aggressive and far more burdensome and costly than the Agency 

envisions. Therefore, the Association’s recommendations set out below would more properly 

balance the goal of better air quality and the costs and burdens associated with implementation.

If a better balance is achieved, the benefits to the consuming public would be enhanced. 

A primary concern of Association Members is the proposed January 1, 2017 implementation date 

for the Tier 3 annual average sulfur standard of 10 ppm. Assuming that the final Tier 3 rule is 

issued by EPA at the end of 2013, refiners and importers would have only three years in which to 

comply. Three years is simply insufficient to make such major modifications.

Fourth, approval for funding for such major changes is a time-consuming and often difficult 

process. The estimated schedule put forth by EPA does not appear to include the time needed to 

obtain or allocate such funding. 

The EPA appears to assume that there would be ample early credits available to assist refiners 

(provide flexibility) in meeting the three-year implementation date by deferring investments. To 

date, there is insufficient information available to EPA and the market about the volume of early 

credits that would or could be generated before the implementation date. Therefore, industry 

could not, during the planning stages, rely on the fact that there would be an adequate supply of 

such credits. 

Recommendation: Accordingly, the Association recommends that EPA amend its proposed rule 

and make the annual average sulfur standard of 10 ppm effective no earlier than January 1, 2019. 

Delay implementation of the proposed Tier 3 standard until at least 2019 to give the regulated 

community sufficient time to make necessary refinery changes in an efficient and cost-effective 

manner; 

Commenter: Irving Oil Terminals Inc.

Irving Oil commends EPA’s efforts to improve air quality through the reduction of sulfur content 

in motor gasoline; however, as outlined in our attached comments, the proposed 2017 Effective 

Date causes great concern because the 10 ppm annual average sulfur content standard cannot be 

achieved as quickly as EPA desires. Typically, the modifications required to comply with the 

proposed standard would be conducted during a five-year turnaround cycle at a refinery during 

which all major renovations, new units and reconfigurations are implemented. A three-year 

implementation period will increase operational risk to refiners, create inefficiencies, increase 
Chapter 5: Tier 3 Fuel Sulfur Program

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expense for many entities and increase the risk of supply disruptions. Industry needs adequate 

time to plan, finance and implement the significant changes required to meet the proposed Tier 3 

standards. A 2019 Effective Date will provide the minimal five-year timeframe for these 

complex and costly adjustments to be implemented. 

Moreover, when the EPA initiated discussions on the Tier 3 rule with the regulated community 

in 2011, it anticipated that the final rule would be issued by 2012, and provided refiners with a 

five-year timeframe to make the necessary adjustments by creating a 2017 Effective Date. Delay 

in issuing the final rule —expected now to be by the end of 2013 — warrants an extension of the 

Effective Date to at least 2019 — thereby preserving the original five-year implementation 

schedule. This proposed timeline is consistent with the previous implementation of both the Tier 

2 and Ultra Low Sulfur Diesel (ULSD) rules. 

Even though the proposed rule has been highly anticipated by the regulated community, design 

approval for major capital investments can only proceed with ‘regulatory clarity’ which will not 

exist until the final rule is issued. 

Accordingly, adoption of the 2019 Effective Date for the 10 ppm annual average sulfur standard, 

along with incentives encouraging the generation of early credits at the earliest possible date, 

will allow industry to achieve compliance in the most efficient and cost-effective manner while 

meeting EPA’s objectives for cleaner air. 

Irving Oil fully supports the Agency’s desire to reduce sulfur in motor gasoline as a means of 

minimizing air pollution as soon as possible. However, as discussed below, the proposed 

effective date— 2017 — will not provide the regulated community with sufficient time to 

implement the changes required and could result in substantial supply chain challenges, supply 

disruptions and unnecessary additional costs. Ensuring compliance with the proposed change in 

sulfur content is a significant undertaking. Accordingly, the EPA should make the effective date, 

January 1, 2019. Assuming the final rule will be issued at the end of 2013, this revised effective 

date would reduce business risk to refiners, allowing time to make the necessary adjustments in 

an efficient and cost-effective manner while continuing to produce adequate supplies of motor 

gasoline to meet consumer demand. 

In the Preamble that accompanied the Proposed Rule, EPA recognizes that gasoline refining is a 

complex operation, and refiners would have to take many steps to comply with the proposed Tier 

3 sulfur standards. These steps include scoping studies, financing, process design for new or 

revamped refinery units or subunits, permitting, detailed engineering based on the process 

design, field construction of the sulfur reduction units, and start-up and shakedown of the newlyinstalled desulfurization equipment. The Agency states that it conducted a lead time analysis and 

spoke with refiners to determine the amount of time that a typical refiner would take to complete 

renovations and meet the 10 ppm sulfur standard. EPA has proposed that a lead time of three 

years is sufficient. The details of the Agency analysis are set out in Table V-3 — ‘Anticipated 

Compliance Timelines.’

Irving Oil has reviewed EPA’s information on ‘lead times’ and believes that it is overly 

optimistic. Also, some of the data on which the determination was made are now out of date due 
Tier 3 Summary and Analysis of Comments

5-75

to major changes that are occurring in the petroleum industry. The following are several 

significant reasons why a three-year lead time is insufficient: 

1. Those companies that license the technology to desulfurize motor gasoline have limited 

resources and likely would be unable to support many simultaneous scoping studies and process 

designs. Thus, some refiners would not be able to begin these activities as early as needed to 

support a three-year lead time. 

2. Irving Oil agrees with EPA’s assessment that most refiners would revamp existing FCC 

gasoline post-treaters rather than constructing grassroots units. However, Irving Oil has often 

found that revamping units, particularly during the early project phases (the scoping study and 

process design) is more complex and time consuming than building and installing an entirely 

new, grassroots unit. Therefore, EPA’s assumption that refiners can revamp existing units more 

rapidly is not supported by Irving Oil’s many years of experience. 

3. EPA has indicated that some of the initial phases of the revamping project can overlap, 

thereby saving additional time. Again, this assumption is contrary to Irving Oil’s experience and 

belief. Irving Oil has found that the process design phase cannot be started until after the scoping 

study is complete. Thus, it is more reasonable to assume that the time needed to make the 

appropriate changes to the refinery would be the same for both a revamping of units and the 

installation of new units. 

4. The EPA believes that there would be sufficient resources (technology licensors, engineering 

and construction services, skilled laborers, and equipment) available to the refining industry. 

However, EPA must recognize that the U.S is undergoing a domestic petroleum renaissance, and 

demand for these resources in new areas of production such as North Dakota, Montana, and 

Texas is great. Those projects would compete for resources directly with refiners trying to meet 

the EPA three-year time schedule. Shortages of these resources would, therefore, likely inhibit 

the ability of refiners to comply in a timely manner. 

5. While the early credit provision of the Tier 3 program may provide refiners with some 

flexibility to meet the proposed January 1 2017 compliance deadline, the number of such credits 

available on the market cannot be predicted with any certainty. Refiners would carefully balance 

the costs associated with the production of lower sulfur motor gasoline in 2014 to 2016 with the 

value derived from selling such early credits. Thus, EPA and the industry cannot assume that 

early credits would provide refiners with enough assistance to comply with the effective dates as 

proposed. 

Recommendations: Change Effective Date to 2019. Irving Oil understands EPA’s desire to 

reduce air pollution by requiring the use of lower sulfur fuels. However, it is essential for the 

EPA to promulgate this new standard in a manner and timeframe that does not disadvantage 

members of the regulated community and provides sufficient time for refiners to plan and 

execute capital investments efficiently. 

Therefore, Irving Oil strongly recommends that EPA change the ‘effective date’ of the proposed 

Tier 3 rule to 2019 — thereby providing at least five years for implementation of this complex 

and costly program. In this way, EPA would achieve its clean air objectives and minimize 

potential supply disruptions and costs associated with compliance that would ultimately be borne 

by consumers. Adoption of 2019 as the effective date and extension of early credits from 2013 

until three years following the effective date would properly balance these important objectives. 
Chapter 5: Tier 3 Fuel Sulfur Program

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Commenter: Marathon Petroleum Company LP (MPC)

The Agency must extend the implementation date until January 1, 2019 or five years after the 

final rule is issued.

EPA asserts that it is necessary to implement the 10 ppm annual average gasoline sulfur standard 

on January 1, 2017 to help heavy duty vehicles meet the Tier 3 vehicle emission standards 

throughout their useful life, to enable new vehicle technologies to improve fuel efficiency, and to 

reduce emissions from the current vehicle fleet. EPA also asserts that 3 years of lead time 

(assuming this rule is finalized by January 1, 2014) provides more than sufficient lead time for 

the refining industry to make the changes necessary to reduce gasoline sulfur levels to 10 ppm on 

average. However, as explained in more detail below, implementation on January 1, 2017 is not 

necessary, and does not provide sufficient lead time. Rather than the 3 years EPA proposes, if 

EPA decides to proceed with the Tier 3 rulemaking, EPA should provide 5 years of lead time to 

implement any changes to the average gasoline sulfur requirement. 

EPA asserts that 3 years of lead time is more than sufficient for the petroleum industry to 

implement the 10 ppm gasoline sulfur requirement. 78 Federal Register 29923. We disagree. We 

suggest that EPA provide 5 years of lead time. As discussed above, rushing implementation of 

the gasoline sulfur requirement is not necessary. Not only is it unnecessary, rushing 

implementation will unnecessarily raise the cost to implement the program. Rushing 

implementation undermines the ability of the industry to adequately plan projects, secure 

contractors and equipment at competitive rates, optimize solutions, and align construction 

projects with existing maintenance turn-around schedules. All of these factors will tend to 

increase compliance costs. 

In the proposal, EPA puts forth Table V-3 with a timeline that the Agency believes illustrates the 

time needed to implement the 10 ppm gasoline sulfur requirement at a refinery. 78 Federal 

Register 29925. We disagree with EPA’s suggested timeline. We believe that a more accurate 

amount of time needed to implement major new rules like the 10 ppm gasoline sulfur

requirement is at least five years. The Tier 2 rules were finalized in February 2000, with 

compliance required to phase in from 2004-06 (with compliance flexibilities that had a more 

meaningful impact, as discussed below). Ultra Low Sulfur Diesel (ULSD) rules were finalized in 

January 2001; with a compliance phase-in period requiring that 15 ppm sulfur diesel constitute 

80% of the highway pool in mid-2006. Compliance lead times need to be longer than these two 

significant rulemakings to reduce sulfur because of new GHG requirements at refiners, and the 

increased reliability of refining equipment has extended refinery turn-around time to 

approximately 5 years. These recent changes for refiners add complexities that warrant 

additional Tier 3 compliance lead time. 

In the proposal, EPA suggests that 3 years of lead time is feasible, in part, because EPA began 

talking to refiners about the possibility of regulating gasoline sulfur a couple of years ago. This is 

inappropriate because EPA decisions concerning key aspects of this rule have not already been 

decided before the Agency even issued this notice of proposed rulemaking. EPA understands that 

there can be many changes made from the time a rule is proposed until it is finalized in response 

to comments submitted by the public, and that therefore there is too much uncertainty to make 
Tier 3 Summary and Analysis of Comments

5-77

detailed implementation plans until the final rule is issued. In this case, for example, we do not 

yet know whether EPA will actually require a reduction in gasoline sulfur given the high costs 

and de minimis environmental benefits, we do not know when the rule will be effective, we do 

not know whether EPA will leave the per-gallon cap at 80 ppm, etc. Based on this, it is 

unreasonable for EPA to assert that refiners had sufficient notice of this rule’s requirements two 

years before it was even proposed to begin implementing the rule. In this rulemaking, as with all 

rules, EPA must consider whether lead time is adequate from the date of promulgation of a final 

rule, not from the time that EPA starts thinking about possibly issuing a proposed rule. 

Commenter: Michigan Department of Environmental Quality (MDEQ)

The deadline proposed should be more than enough time given that the technology and methods 

are already available. 

Commenter: Mid-Atlantic Regional Air Management Association Inc. (MARAMA)

MARAMA states recognize that the proposed rules may increase costs for some refineries 

located in this region, and raise the cost of gasoline. MARAMA supports EPA’s efforts to 

mitigate those costs by providing time to install needed equipment at refineries. 

Commenter: Monroe Energy, LLC

In addition, the controls will take at least 2 years to design and engineer and will necessitate a 

shutdown of the refinery for tie-in. Like most refineries in the United States, Monroe operates on 

a 5 year turnaround cycle. Monroe’s next turnaround is scheduled for 2018. Therefore, in order 

to comply in a timely manner with the Tier 3 gasoline sulfur standard, Monroe would be forced 

to take an out of sequence maintenance turnaround, shutting off its production and costing the 

refinery millions of dollars of lost operating revenues, or it will be forced to buy credits from 

other refiners in order to comply. EPA’s rules should provide sufficient lead time so that refiners 

have time to install controls and are not required to rely on purchasing credits from other refiners 

in order to comply. Therefore, the rule should give refiners no less than six years to comply from 

the time the rule is issued to ensure that all refiners have adequate lead time to design, engineer, 

and install controls without taking unscheduled or out of sequence turnarounds or buying credits 

from other refiners. 

Commenter: New York State Department of Environmental Conservation

EPA estimates (Chapter 4 of the RIA) that three years will be necessary for the design, 

permitting, construction and commissioning of grass roots Fluid Catalytic Cracking (FCC) 

gasoline hydrotreaters. Revamps are expected to require two years. The Tier 3 proposal provides 

more than three years lead time, six for smaller refineries. Even if there are cases where three 

years are insufficient, the Averaging, Banking, and Trading provisions of the proposed rule 

provide additional compliance flexibility. 
Chapter 5: Tier 3 Fuel Sulfur Program

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While industry-wide compliance significantly earlier than 2017 may be difficult to achieve, the 

proposed compliance dates provide ample time for industry to make the changes needed to 

reduce gasoline sulfur content, and should be promulgated unchanged. 

Commenter: PBF Energy Inc.

PBF conducted a preliminary facility review to evaluate the modifications needed to comply 

with the new proposed fuel standards. We found that all three PBF refineries will require 

significant investments to comply with the proposed new regulation to meet the 10 ppm annual 

average gasoline sulfur standard. 

Additionally, PBF is concerned that the timing of this regulation when coupled with the impact 

of other fuels regulatory programs RFS2, Ozone NAAQs, and Northeast States switching to 15 

ppm sulfur home heating oil places a significant regulatory related economic burden at the same 

time the EPA is proposing to enact the new Tier3 gasoline sulfur standards. The Northeast 

gasoline market is highly competitive and the imposition of the added regulatory compliance 

costs associated with each program will have a significant impact on business outlook, regional 

investment decisions, and PBF’s competitiveness versus imported gasoline products. 

PBF requests that the EPA review the timing of all regulatory impacts and defer the 

implementation of the Tier 3 gasoline sulfur standard until it is actually needed by the new Tier 3 

motor vehicles being rolled out with the most stringent fuel requirements at the end of the 

vehicle early credit program. 

Commenter: Phillips 66 Company

Implementation date - The January 1, 2017 implementation date does not provide sufficient lead 

time for refineries to complete needed capital projects. 

The API and AFPM comments provide detailed analysis of EPA’s justification of the proposed 

10 ppm average sulfur standard. These comments address the areas of the technical need for a 10 

ppm sulfur level, the environmental impact, and the cost-benefit analysis. Phillips 66 participated 

in the development of these comments, agrees with the content, and questions the justification 

for the revised sulfur standards. We are not specifically addressing these aspects of the 

rulemaking in our comments but are relying on the API/AFPM comments to convey our views 

on these issues. 

Implementation Date – January 1, 2017 does not provide sufficient lead time for refineries to 

complete projects.

The proposed implementation date of January 1, 2017 does not provide adequate lead time for 

refineries to implement needed capital projects. EPA has proposed this aggressive timeline and 

uses two basic arguments to support their proposal. Firstly, EPA predicts that most projects will 

be of moderate scope and therefore refiners can complete needed capital projects within a 3-year 

time frame. Based on our initial analysis, we expect our company (and likely industry) will be 

faced with projects of significant scope requiring more than 3 years to complete. 
Tier 3 Summary and Analysis of Comments

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Project Scope: EPA provided two project timeline estimates in the proposed rule – one for unit 

revamps (24 months) and one for new grass roots units (36 months). We believe EPA has 

underestimated the time requirement for every phase of a project – whether a revamp or a new 

unit. 

In its investigations, EPA concludes that most refineries will require only projects of moderate 

revamp scope and that a relatively few will require grass roots desulfurization investments. The 

DRIA is quoted, “For companies that already have an FCC naphtha postreater we assumed that 

all that would be necessary to meet the proposed sulfur standards was to revamp their existing 

FCC postreating units.” Also in its analysis, EPA uses a PADD average approach which may 

neglect individual refinery configurations. 

To reduce sulfur in gasoline, it is common for refiners to separate the FCC naphtha stream into 

several streams with differing characteristics requiring different treatment technologies. Some of 

these separated streams, but not all, may currently be undergoing sulfur reduction. The likely 

approach to achieving Tier 3 will be to treat the remaining FCC streams plus additional light 

streams from other process units. Due to the differences in characterization, the in-place 

technology likely will not be appropriate to treat the remaining untreated stream(s) required for 

Tier 3 and therefore revamp(s) would not be chosen. For example, heavy FCC naphtha contains 

a significantly higher amount of sulfur and uses a technology that is not appropriate for light 

FCC naphtha. In cases where a refinery is currently only treating the heavy FCC naphtha, 

refiners will require new grass roots units to treat other portions of the FCC naphtha, tailored to 

the individual characteristics of the untreated streams. 

These extensive projects and the fact that industry will be competing for many of the same 

engineering, procurement and field resources to complete them, requires significantly more time 

than EPA is providing in its proposal. 

Project time requirements: Our experience with both grassroots projects and significant revamps 

of this magnitude is that they require well in excess of three years to complete. As such, EPA 

should extend the compliance date to coincide with 5 years from issuance of the final rule. 

Below are two projects time lines, for a grassroots and revamp, provided by Phillips 66 internal 

project management staff. As shown the grass roots projects will need almost 5 years to 

complete. By comparison, the revamp project can be completed in only 6 months less time. As 

such, we believe that EPA has underestimated the time requirement and uncertainty for every 

phase of a project. 

In particular, a critical phase of any project is in the initial scoping. It is imperative that refineries 

take the requisite time needed to fully evaluate various technology options and operating 

configurations. It may be necessary to incorporate other facets into the project, such as 

alleviating existing bottlenecks to allow full operational optimization and flexibility with any 

new or revamped units. Technology vendors continue to work on improvements especially in the 

area of catalyst technology. It is a very time consuming effort to work with multiple technology 

vendors to evaluate various feed streams with their technologies and then do economic 

evaluations on the different options. In order to meet a January 1, 2017 implementation date, a 
Chapter 5: Tier 3 Fuel Sulfur Program

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refinery would need to have already completed the project scoping phase, well in advance of the 

final rule. Since there is uncertainty in when the final rule will be issued, and in the provisions it 

will contain, refiners cannot set a final design basis. They therefore cannot complete scoping 

until the final rule is issued. 

The industry is requesting a lead time of 5 years from final rule issue, should EPA proceed with 

a modification of the standard. This timing would provide sufficient lead time and would fit 

better with the 5-year refinery turnaround cycles. 

The proposed changes in gasoline sulfur level represent a significant change and one that will 

require wide scale refinery investment. Although EPA did initially start talking about potential 

changes to the gasoline sulfur standards almost two years ago, it did not promulgate a notice of 

proposed rulemaking until May 21, 2013. EPA has proposed a very aggressive implementation 

date of January 1, 2017 for the proposed new standard to take effect. EPAs justification for this 

short implementation timing is a combination of estimated project timelines and ability to 

generate early credits to help forestall capital investment. Phillips 66 believes that the Agency 

has been overly optimistic in both their estimate of required time for various project phases as 

well as the refining industry’s ability to generate early credits. Refineries that require 

modifications be complete in order to meet the new standard need more time than what is 

proposed to complete their projects. Existing units are limited in their capability to further reduce 

sulfur content and the collective cost to generate early credits may be very high (lost octane, 

shortened run length that would necessitate additional shut down, etc.). Phillips 66, along with 

others in the industry, is requesting EPA provide a 5 year lead time to allow needed project 

completion. 

Commenter: Shell Oil Products for Shell and Motiva

EPA is proposing to make the 10 ppm annual average gasoline sulfur standard effective on 

January 1, 2017. Assuming that EPA issues the final rule by the end of 2013, that leaves only 

three years of lead time. We urge EPA to provide additional lead time. Three years is simply not 

enough time to allow obligated parties to adequately plan and implement the changes that will be 

necessary to reduce sulfur from the current 30 ppm annual average standard to the 10 ppm 

standard. It also does not allow refiners to optimize their plans and to integrate the necessary 

changes into existing turn-around and maintenance plans. The result of such a rushed 

implementation is likely to be higher compliance costs, which could translate in to higher prices 

for consumers. 

Our Response:

We received several requests for extension of time from 3years to 5years. These requests 

justified the additional time on grounds of compliance costs and state/federal permitting 

requirements resulting from new regulations such as the GHG rule. Several commenters also 

stated that we had underestimated the project time lines for revamps and installation of 

grassroots units. 
Tier 3 Summary and Analysis of Comments

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We disagree with the comments that a 3 year lead time is insufficient for refiners to comply with 

today’s sulfur standards. We acknowledge that an adequate amount of lead time is required for 

the implementation of any rulemaking. Depending on the level of effort required to comply, 

more or less lead time is also required. Section 211(c) of the Act is silent on the compliance date 

for standards promulgated there under. We are therefore exercising our discretion in setting an 

appropriate compliance period for today’s standards. In doing so we have considered various 

factors such as the time needed to select the technology and the vendor that will provide the 

technology with which they will comply with the fuels standard; time needed to arrange an 

engineering and construction (E & C) contractor which will design and oversee the construction 

of the refinery unit and the time needed to obtain the necessary permits and procure the 

necessary hardware. Further, we have considered the time needed to construct the unit and the 

time needed to make the necessary unit tie-ins of the unit with the rest of the refinery and then 

startup the unit. In response to these time considerations, we have provided a generous ABT 

program as well as provisions allowing for the phase-in of sulfur standards beginning in 2017 

and through 2019. As also previously explained, EPA is also adopting Tier 3 emissions standards 

for motor vehicles under section 202. These vehicle standards begin to phase-in for vehicles less 

than 6000lbs GWVR with the 2017 model year. As discussed in Section IV.A.6 of the preamble,

for new vehicles, the use of 10 ppm average sulfur fuel is an essential part of achieving Tier 3 levels 

while applying an array of advancements in emissions control technology to the light-duty fleet.

The commenters supporting more lead time, focused solely on the January 1, 2017 start 

date and failed to take into account that the standard is actually phased-in through the flexibilities 

provided through 2019. Focusing solely on the January 1, 2017 start data for larger refineries 

does not reflect the significant flexibilities provided by the Tier 3 averaging, banking, and 

trading provisions, the delayed start for small refiners and small volume refineries, the ability to 

carry over credits from Tier 2, and the availability of hardship relief as a failsafe. Were the 

program to have been designed without these flexibilities, then their comments would have been 

more relevant. With these flexibilities, the final Tier 3 program provides ample lead time.

As discussed in Section V.D of the preamble to the final rule, we are finalizing an

averaging, banking and trading (ABT) program that would significantly help refiners comply 

with the January 1, 2017 start date. There are three provisions of the ABT program which help 

with respect to leadtime and we have concluded that when these ABT provisions are taken into 

account, refiners will essentially have the equivalent of 6 years of leadtime. The ABT program 

allows for ongoing intra-company and inter-company trading nationwide. This will allow some 

refineries to over-comply with the 10 ppm gasoline sulfur standard (in our analysis, we modeled 

these refineries bringing their gasoline down to 5 ppm), allowing other refineries that would 

otherwise need to install grassroots units to not invest and purchase credits instead. This aspect 

of the ABT program is very important because our analysis estimates that only one refinery 

would need to install a grassroots hydrotreater whereas without the ABT provisions, there could 

be as many as 20 grassroots units. This one aspect has important implications for leadtime 

because as discussed in the above, revamps require two years or less whereas grassroots FCC 

postreater units require approximately three years to install. We are convinced that this aspect of 

the ABT program will be utilized to the maximum extent possible because refineries revamping 

their postreaters in lieu of installing grassroots postreaters results in the most cost-effective 

mechanism for meeting the 10 ppm annual average standard. 
Chapter 5: Tier 3 Fuel Sulfur Program

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An important question is whether refiners will not invest in a grassroots unit trusting that 

the credits will be freely available. For the NPRM, we conservatively assumed that refiners 

would only rely on credits if they could generate them internal to the company. As discussed in 

Section V.L. of the preamble and Chapter 4.4 of the RIA, we assessed how the sulfur credits 

were being traded under Tier 2 and we found that over half the sulfur credits were freely traded 

between companies (as opposed to only being used within companies), and many single-refinery 

companies had sulfur levels above 30 ppm (single-refinery companies must purchase credits 

from other companies). Because we set up the Tier 3 credit trading program to work just like the 

Tier 2 credit trading program, we are confident that there will be widespread trading within and 

between refining companies which means that few grassroots units will be need to be built for 

Tier 3.

 

A second aspect of the ABT program that helps with leadtime is the provision for 

generating early sulfur credits and banking them for later use. This provision allows refineries to 

reduce their gasoline sulfur to less than 30 ppm prior to January 1, 2017 and bank the credits for 

later use. Based on comments that we received on the proposed rule, we are allowing Tier 2 

credits which are generated during the years 2012 and 2013 to also be used to show compliance 

for Tier 3. This effectively extends the early credit generation period for Tier 3 to encompass the 

years 2012 to 2016, which is 5 years. Analyzing the 2012 gasoline quality data that refiners 

reported to EPA, we found that gasoline sulfur levels in the U.S. averaged 26.7 ppm. Thus, 

refiners have already begun overcomplying with Tier 2 by 3.3 ppm, and are therefore already 

generating early credits for Tier 3. If refiners do nothing more but continue to overcomply with 

Tier 2 by 3.3 ppm over the 5 years of early credit generation, refiners will have generated enough 

credits to delay the completion of their capital projects by more than one year. Furthermore 

since those credits generated in 2012 and 2013 will expire in 2017 and 2018 respectively, 

refiners will have an incentive to either use them themselves or trade them in 2017 and 2018. 

Thus refiners that may need to count on them to delay their capital investment are likely to be 

able to have access to them.

 

We believe that refiners will generate a lot more early credits with their existing gasoline 

sulfur control units than the 3.3 ppm we observed in 2012. As we discussed in our cost analysis, 

to produce more diesel fuel in response to a greater demand for diesel fuel relative to gasoline, 

refiners are undercutting the swingcut portion of FCC naphtha at their refineries.1 This action to 

shift what historically was blended into the gasoline pool to the diesel fuel pool, also 

dramatically reduces the sulfur content of the gasoline pool. If the entire swingcut portion of 

FCC naphtha is undercut to the diesel fuel pool, the amount of sulfur in the gasoline pool is 

reduced by about 50 percent. Our cost analysis estimates that at almost one quarter of U.S. 

refineries, refiners are fully undercutting the FCC naphtha to diesel fuel today. At many other 

refineries, our cost analysis estimates that refiners are partially undercutting their FCC naphtha. 

These refineries will be able to reduce the sulfur of their gasoline well below their current levels 

and generate a large number of early credits for Tier 3. Even for the subset of refineries where 

FCC naphtha is not being undercut, refiners can assess how much activity or catalyst life is left 

in its FCC postreater catalyst and compare this time with the time to the next turnaround when 

the FCC postreater catalyst is scheduled to be replaced. If there is spare catalyst life, the refiner 

 

1 The term swingcut means that this portion of the FCC product pool can be blended into gasoline or diesel fuel 

while still meeting the fuel quality specifications for either fuel regardless of where this swingcut is blended. 
Tier 3 Summary and Analysis of Comments

5-83

could elect to increase the severity of their postreaters to reduce their gasoline sulfur levels to 

under 30 ppm. With this strategy, the refiner would generate early sulfur credits. Also, when the 

refiner replaces the catalyst in its Tier 2 postreater, it can elect to do so with a more active 

catalyst which would allow the refinery to produce gasoline at sulfur levels below 30 ppm and 

generate more early credits for Tier 3.

 

Based on the early actions refiners are either already taking, or could take, to reduce their 

gasoline sulfur levels, we believe that refiners would be able to reduce their gasoline sulfur to as 

low as 20 ppm, on average, without making any capital investments. By averaging 20 ppm for 

2.5 years prior to 2017, refiners would be able to delay completion of all capital investments for 

Tier 3 until mid 2019. If we add the 3.3 ppm of credits during 2012, 2013 and first part of 2014, 

refiners would be able to delay completion of all capital investments in Tier 3 until 2020. Thus, 

the early credit provisions in-effect can provide nearly 6 years of leadtime for full compliance 

with the fuels program. This will allow ample time for refiners to complete their investment and 

schedule their tie-ins during normal shutdown activities. It effectively provides even more lead 

time than 5 years that the refining industry requested in their comments. The delay in the 

program implementation will also help to distribute the demand on the E & C industry over more 

years ensuring that the E & C industry would not be overwhelmed. Thus, the Tier 3 program 

with a very flexible ABT program provides ample leadtime. In chapter 4 of the RIA we provide 

multiple examples of how the refining industry can comply with the January 1, 2017 start date 

which accounts for the types of projects that will need to be installed, a range of the credit 

market size that will exist and the timing associated with tying-in the revamp or grassroots unit 

with the rest of the refinery. 

 

As discussed in more detail in Section V.E.1 of the preamble, the provisions for small 

refiners and small volume refineries is a third aspect of the Tier 3 ABT provisions that helps 

with leadtime. Small refiners and small volume refineries (i.e., refineries processing less than or 

equal to 75,000 net barrels per day of crude oil) are exempted from complying with the 10 ppm 

average sulfur standard until 2020. This provides an estimated 36 refineries, of the total 108 

refineries, nearly 6 years of lead time; again more than the 5 years that the refining industry 

requested in their comments. As a group, we believe that these refiners and refineries are

disproportionally impacted when it comes to their cost of compliance and ability to rationalize 

investment costs in today’s gasoline market. Giving these refiners and refineries additional lead 

time provides more time to invest in desulfurization technology, take advantage of advancements 

in technology, develop confidence in a Tier 3 credit market as a means of compliance, and avoid 

competition for capital, engineering, and construction resources with the larger refineries. The 

small refiner and small volume refinery exemption until 2020 reduces the number of refineries 

which will need to make a significant capital investment to comply with Tier 3 prior to 2020 to a 

total of 49 non-small refineries (48 revamps and 1 grassroots unit), thus 15 refineries could wait 

to take action until 2020. Although the small refiners and small volume refineries are not 

required to comply with Tier 3 until 2020, they can still generate early credits (from January 1, 

2017 through December 31, 2019) relative to 30 ppm for sale to other small refiners/small 

volume refineries, and relative to 10 ppm for sale to non-small refiners. Such credits generated 

relative to 10 ppm could provide another pool of early credits for Tier 3.
Chapter 5: Tier 3 Fuel Sulfur Program

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In summary, the ABT program provides ample flexibility for complying with Tier 3. The 

averaging provisions will allow refiners that only need to revamp their Tier 2 postreaters to 

overcomply and generate credits which will allow refineries that otherwise need to install 

grassroots units to comply solely through the purchasing of credits. The banking provisions, 

which allow refiners to generate early credits, effectively delays investments for compliance to 

potentially as late as the year 2020. Finally, the small refiner and small refinery provisions delay 

compliance for approximately 30 refiners until 2020. The provisions also allow them to generate 

and sell credits during this period if they so choose. All these ABT provisions effectively 

address the leadtime concerns. Furthermore, were we to shift the start date back another 2 years 

as the refinery industry suggests in their comments, it would provide nearly 8 years of leadtime 

for refinery changes that require just 2 or 3 years to complete. Refiners would not have to even 

begin taking action for Tier 3 for a couple of years. Given that the lead time and associated 

programmatic flexibility we are finalizing is sufficient to allow industry to readily comply, we do 

not expect that a delay in the start date of the fuel standards would change the cost of compliance

discussed in Chapter 5. Any further delay in the program start date would simply delay the 

actions to comply. Furthermore, delaying the start of the program would forego significant 

emissions, air quality, and health benefits.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

In the proposal, EPA suggests that 3 years of lead time is feasible, in part, because EPA began 

talking to refiners about the possibility of regulating gasoline sulfur a couple of years ago. This is 

inappropriate because EPA decisions concerning key aspects of this rule are not yet final. EPA 

understands that there can be many changes made from the time a rule is proposed until it is 

finalized in response to comments submitted by the public, and that therefore there is too much 

uncertainty to make detailed implementation plans until the final rule is issued. In this case, for 

example, we do not yet know whether EPA will actually require a reduction in gasoline sulfur 

given the high costs and de minimis environmental benefits, we do not know when the rule will 

be effective, we do not know whether EPA will leave the per-gallon cap at 80 ppm, etc. Based on 

this, it is unreasonable, and arguably a violation of the Administrative Procedures Act, for EPA 

to assert that refiners had sufficient notice of this rule’s requirements two years before it was 

even proposed to begin implementing the rule. In this rulemaking, as with all rules, EPA must 

consider whether lead time is adequate from the date of promulgation of a final rule, not from the 

time that EPA starts thinking about possibly issuing a proposed rule. 

Our Response:

Our leadtime assessment is based on complying after the Tier 3 rulemaking is 

promulgated. The conversations we held with refining companies only figured into the means 

for compliance.

5.1.4.3.2. Impact of Turnaround Timing on Leadtime
Tier 3 Summary and Analysis of Comments

5-85

What Commenters Said:

Commenter: Phillips 66 Company

Additionally, industry turnaround Intervals are typically every 4 to 5 years. An implementation 

date of January 1, 2017, about 3 1/2 years from publication of the proposed rule does not sync 

well with the refinery cycles. For example, if a refinery’s normal turnaround date is 2014 and

again in 2019, there is not enough time to design, plan and execute the needed modifications 

during the 2014 shutdown. In this case, refiners would be forced either to use credits in 2017, 

2018 and part of 2019 until they could complete projects or to take a shut downs outside of 

normal turnaround intervals. We question the availability of adequate credits available to 

industry and believe that many refineries will require process unit shutdowns ahead of schedule. 

Commenter: Chevron Products Company

The 2017 start date may have a negative impact on gasoline supply during the implementation 

phase of the program. Ideally, refiners would be able to schedule investment to correspond with 

their existing maintenance schedules, which often occur on 4 to 5 year intervals. Requiring 

investments and construction to occur in a limited three-year window may compel refineries to 

schedule additional off-cycle turnarounds which can reduce refinery utilization rates and also 

reduce the supply of products to the market. 

Commenter: Irving Oil Terminals Inc.

Irving Oil commends EPA’s efforts to improve air quality through the reduction of sulfur content 

in motor gasoline; however, as outlined in our attached comments, the proposed 2017 Effective 

Date causes great concern because the 10 ppm annual average sulfur content standard cannot be 

achieved as quickly as EPA desires. Typically, the modifications required to comply with the 

proposed standard would be conducted during a five-year turnaround cycle at a refinery during 

which all major renovations, new units and reconfigurations are implemented. A three-year 

implementation period will increase operational risk to refiners, create inefficiencies, increase 

expense for many entities and increase the risk of supply disruptions. Industry needs adequate 

time to plan, finance and implement the significant changes required to meet the proposed Tier 3 

standards. A 2019 Effective Date will provide the minimal five-year timeframe for these 

complex and costly adjustments to be implemented. 

Every year, refineries shut down select units in their facilities and perform regular inspections 

and maintenance. These planned ‘turnarounds’ last about four weeks and are time-consuming 

and disruptive, but they provide refiners the opportunity to make small adjustments to capacity, 

improve fuel quality to some degree, repair, clean and update units. Typically, most maior 

processing units undergo such turnarounds approximately every five years on a staggered 

schedule. It is also during these unit turnarounds that any required revamp upgrades are 

performed, which can extend turnaround durations beyond four weeks. These revamps can be 

minor or major in magnitude. Units can be modified or replaced, capacity may be increased, and 

there may be overall reconfiguration. The changes associated with this type of turnaround can be 

significant. They typically take years to plan, design, purchase equipment and install, and such 
Chapter 5: Tier 3 Fuel Sulfur Program

5-86

changes can cost hundreds of millions of dollars. The refinery changes necessary to meet the 

proposed annual average sulfur standard of 10 ppm may fall within these latter types of 

modifications and would be most efficiently implemented as part of a comprehensive refinery 

turnaround. 

Unfortunately, the proposed rule does not give consideration to these normal refinery turnaround 

cycles. It simply proposes an effective date that is approximately three years from the anticipated 

date when the final rule will be issued. Three years is not sufficient. Moreover, Irving Oil 

understands that when EPA first began work on the Tier 3 rule in 2010 and thought that a final 

rule would be issued in 2012, an effective date of 2017 was appropriate. It would have provided 

industry with five years to meet the proposed standard. However, because the proposed and final 

rules were delayed, the effective date for the 10 ppm sulfur standard should also be adjusted 

accordingly. An implementation date that provides five years would generally align with the 

turnaround cycle for most refiners. A shorter date would inadvertently place some at a significant 

financial and competitive disadvantage. Such refiners would either be forced to buy credits to 

meet the new standard or perform an additional turnaround — an inefficient and costly measure. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

The increased reliability of refining equipment has extended refinery turn-around time to 

approximately 5 years. 

Commenter: Marathon Petroleum Company LP (MPC)

The increased reliability of refining equipment has extended refinery turn-around time to 

approximately 5 years. 

Our Response:

We also received comments indicating that the January 1, 2017 does not complement 

refinery turnaround schedules, which often occur in 4-5 year intervals.

We agree that the need to make tie-ins, which must occur during a refinery turnaround, 

must be considered when assessing the feasibility of leadtime, and even when we factor the time 

needed to do so, our analysis shows that refiners can comply with Tier 3 with the leadtime 

provided. This is true because the final rule effectively provides nearly 6 years of leadtime to 

complete capital projects, and also because the capital projects do not have to be completed prior 

to installing the necessary tie-ins for new Tier 3 units.

As explained in Section V.L of the preamble to today’s final rule, when a refiner builds a 

grassroots unit or some sort of revamp that involves a new reactor or perhaps an added

distillation column, the new vessels and associated equipment must be “tied-in” to the rest of the 

refinery. The tie-in usually involves connecting a pipe from the existing unit to the new unit 

installed. However, a pipe cannot simply be added while the refinery is operating. Instead, the 

refiner will add the necessary pipe for making the tie-in when the refinery, or at least that 
Tier 3 Summary and Analysis of Comments

5-87

refinery unit, is shutdown for regular maintenance. The revamp or grassroots unit does not have 

to be started up at that time, thus, the tie-in piping can be added well before the revamp or 

grassroots unit is completed. Instead, the connection pipe just needs to be added and blocked off 

with a sealing-type valve and a blind flange (essentially a flat piece of steel) is bolted on as a 

precaution against a leaky valve. This is a very simple process that would take several pipefitters 

a half a day of work to complete including completing all the necessary safety protocols.2 Once 

this piping has been added, the refiner can restart its refinery. Then when the refiner is ready to 

complete the tie-in to the completed revamp or grassroots unit, the refiner would remove the 

blind flange and connect a pipe that connects the existing part of the refinery to the newly 

installed grassroots postreater unit or revamp postreater subunit. This last step can either occur 

when the refinery is shutdown or still operating. At that point the refiner would only need to 

open the block valve to complete the tie-in of the grassroots unit or revamp to the existing 

refinery. One refiner who owns a number of refineries informed us that it installed the tie-ins for 

a possible Tier 3 rule when it installed its Tier 2 units.

Refiners commented that FCC turnarounds occur on a 4 to 5 year basis, or a 5 year basis. 

However, this amount of time between FCC turnarounds is contradicted based on information 

provided on the American Petroleum Institute’s webpage, which reports that the average time 

between major FCC unit turnarounds is 4 years. Also, an Energy Information Administration 

(EIA) study makes a similar finding, which is that refiners target 3 – 5 years, or 4 years on 

average, between refinery turnarounds. The EIA study also reported the results of an Octane 

Week survey of about 20 refineries which found that refiners target 4 - 5 years between 

turnarounds of the FCC units, but over 25% of the time refiners need to conduct turnarounds 

earlier than targeted because a maintenance issue forces the earlier turnaround. However, the 

EIA study did not estimate how much earlier the turnaround occurred so it was not possible to 

estimate an actual average turnaround schedule, which may be less than 4 years. This means that 

on average, 25% of U.S. refineries shutdown to perform maintenance on its FCC units each year.

In Chapter 4 of the RIA, we presented our analysis of several different scenarios for 

credit availability versus demand for complying with the Tier 3 sulfur standard, assuming that 

credits will be traded nationwide as it has under Tier 2. In one scenario, if refiners reduce their 

gasoline sulfur to 20 ppm immediately after the Tier 3 rule is finalized, as we anticipate they are 

capable of, then the substantial number of early credits generated would allow refiners to delay 

their unit start-ups sufficiently for refiners to not only make the tie-ins, but even complete their 

capital projects as necessary. However, we also conducted a more conservative analysis which 

assesses the ability of refiners to comply with Tier 3 if they generate no or few early credits. 

Using the estimate that turnarounds are scheduled at refineries every 4 years, we also found that 

refiners would be able to comply with the Tier 3 program start date. 

 

2

 Since most refiners have already completed their scoping studies with the vendor companies which license the 

desulfurization technologies, they likely already understand what steps would need to be taken to tie-in their 

revamps and grassroots units with their existing refinery. Installation of tie-ins is relatively simple refinery change 

that can be engineered and installed in a short period of time. For this reason, we believe that refiners can begin 

making their tie-ins as soon as the spring of 2014

3

40 CFR 80.385(e).
Chapter 5: Tier 3 Fuel Sulfur Program

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5.1.4.3.3. Amount of Time Required to Install Grassroots Units and Revamp Existing 

Units

What Commenters Said:

Commenter: Phillips 66 Company

The proposed implementation date of January 1, 2017 does not provide adequate lead time for 

refineries to implement needed capital projects. EPA has proposed this aggressive timeline and 

uses two basic arguments to support their proposal. Firstly, EPA predicts that most projects will 

be of moderate scope and therefore refiners can complete needed capital projects within a 3-year 

time frame. Based on our initial analysis, we expect our company (and likely industry) will be 

faced with projects of significant scope requiring more than 3 years to complete. 

Project Scope: EPA provided two project timeline estimates in the proposed rule – one for unit 

revamps (24 months) and one for new grass roots units (36 months). We believe EPA has 

underestimated the time requirement for every phase of a project – whether a revamp or a new 

unit. 

In its investigations, EPA concludes that most refineries will require only projects of moderate 

revamp scope and that a relatively few will require grass roots desulfurization investments. The 

DRIA is quoted, “For companies that already have an FCC naphtha postreater we assumed that 

all that would be necessary to meet the proposed sulfur standards was to revamp their existing 

FCC postreating units.” Also in its analysis, EPA uses a PADD-average approach which may 

neglect individual refinery configurations. 

To reduce sulfur in gasoline, it is common for refiners to separate the FCC naphtha stream into 

several streams with differing characteristics requiring different treatment technologies. Some of 

these separated streams, but not all, may currently be undergoing sulfur reduction. The likely 

approach to achieving Tier 3 will be to treat the remaining FCC streams plus additional light 

streams from other process units. Due to the differences in characterization, the in-place 

technology likely will not be appropriate to treat the remaining untreated stream(s) required for 

Tier 3 and therefore revamp(s) would not be chosen. For example, heavy FCC naphtha contains 

a significantly higher amount of sulfur and uses a technology that is not appropriate for light 

FCC naphtha. In cases where a refinery is currently only treating the heavy FCC naphtha, 

refiners will require new grass roots units to treat other portions of the FCC naphtha, tailored to 

the individual characteristics of the untreated streams. 

These extensive projects and the fact that industry will be competing for many of the same 

engineering, procurement and field resources to complete them, requires significantly more time 

than EPA is providing in its proposal. 

Project time requirements: Our experience with both grassroots projects and significant revamps 

of this magnitude is that they require well in excess of three years to complete. As such, EPA 

should extend the compliance date to coincide with 5 years from issuance of the final rule. 
Tier 3 Summary and Analysis of Comments

5-89

Below are two projects time lines [EPA-HQ-OAR-2011-0135-4463-A1], for a grassroots and 

revamp, provided by Phillips 66 internal project management staff. As shown the grass roots 

projects will need almost 5 years to complete. By comparison, the revamp project can be 

completed in only 6 months less time. As such, we believe that EPA has underestimated the time 

requirement and uncertainty for every phase of a project. 

In particular, a critical phase of any project is in the initial scoping. It is imperative that refineries 

take the requisite time needed to fully evaluate various technology options and operating 

configurations. It may be necessary to incorporate other facets into the project, such as 

alleviating existing bottlenecks to allow full operational optimization and flexibility with any 

new or revamped units. Technology vendors continue to work on improvements especially in the 

area of catalyst technology. It is a very time consuming effort to work with multiple technology 

vendors to evaluate various feed streams with their technologies and then do economic 

evaluations on the different options. In order to meet a January 1, 2017 implementation date, a 

refinery would need to have already completed the project scoping phase, well in advance of the 

final rule. Since there is uncertainty in when the final rule will be issued, and in the provisions it 

will contain, refiners cannot set a final design basis. They therefore cannot complete scoping 

until the final rule is issued. 

Commenter: Monroe Energy, LLC

The controls will take at least 2 years to design and engineer.

Commenter: Chevron Products Company

We are opposed to the implementation schedule proposed by the EPA. The 2017 compliance 

deadline does not provide sufficient time to make necessary refinery modifications and would 

significantly increase the cost of the required upgrades. If the agency proceeds with the gasoline 

sulfur reduction requirement, the program start date should be no sooner than five years after the 

date of the final regulation. 

We agree that the technology for sulfur reduction to the 10 ppm level is available and has been 

demonstrated at certain refineries in operation today. However, we believe that EPA has 

underestimated the cost and complexity of the changes which will be required in the refining 

industry to achieve this reduction. 

The time required for permitting is becoming longer due to local regulations and GHG programs. 

We do not agree that the analysis of permit times should be limited to the estimates provided by 

OAQPS. We are seeing other government agencies placing additional requirements on refinery 

permits for a variety of GHG, safety, and environmental concerns, all of which increase the time 

required to obtain a permit. California refineries producing gasoline subject to the Tier 3 

regulations may encounter even longer permitting times and increased scrutiny, taking them well 

beyond the proposed implementation period. 

We are also concerned about EPA’s statement that many refineries have already started scoping 

work on investments in advance of the Tier 3 rulemaking. While it is true that refineries have 
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been aware of EPA’s intention to conduct a Tier 3 rulemaking for over two years, the NPRM 

was only published in the Federal Register on May 21, 2013, and will not be finalized until late 

2013. It is unlikely that refineries have conducted significant planning or engineering based on 

speculation about Tier 3 when there has been no certainty about the timing or the specific 

requirements of the rule until very recently. The timeline for program implementation should be 

based on realistic estimates of the time required for planning, investment, permitting, 

construction, and operation, and refineries should be able to conduct these activities to fully 

comply on day one of the new program. To suggest that the timeline could be shortened based on 

actions that refiners may have taken prior to even a proposed rulemaking is inappropriate. 

Chevron is concerned about the global availability of long lead time equipment, like reactors and 

compressors, which will be required for many of the industry projects. Refinery investments 

require specialized labor for both design and construction. These industries are experiencing a 

great demand for services due to other domestic energy investment projects currently underway. 

EPA’s analysis of the capability of the labor force does not fully consider the competition for 

these resources and the impact this may have on the timelines required for Tier 3 investments.

Commenter: Irving Oil Terminals Inc.

Even though the proposed rule has been highly anticipated by the regulated community, design 

approval for major capital investments can only proceed with ‘regulatory clarity’ which will not 

exist until the final rule is issued. 

Every year, refineries shut down select units in their facilities and perform regular inspections 

and maintenance. These planned ‘turnarounds’ last about four weeks and are time-consuming 

and disruptive, but they provide refiners the opportunity to make small adjustments to capacity, 

improve fuel quality to some degree, repair, clean and update units. Typically, most maior 

processing units undergo such turnarounds approximately every five years on a staggered 

schedule. It is also during these unit turnarounds that any required revamp upgrades are 

performed, which can extend turnaround durations beyond four weeks. These revamps can be 

minor or major in magnitude. Units can be modified or replaced, capacity may be increased, and 

there may be overall reconfiguration. The changes associated with this type of turnaround can be 

significant. They typically take years to plan, design, purchase equipment and install, and such 

changes can cost hundreds of millions of dollars. The refinery changes necessary to meet the 

proposed annual average sulfur standard of 10 ppm may fall within these latter types of 

modifications and would be most efficiently implemented as part of a comprehensive refinery 

turnaround. 

In the Preamble that accompanied the Proposed Rule, EPA recognizes that gasoline refining is a 

complex operation, and refiners would have to take many steps to comply with the proposed Tier 

3 sulfur standards. These steps include scoping studies, financing, process design for new or 

revamped refinery units or subunits, permitting, detailed engineering based on the process 

design, field construction of the sulfur reduction units, and start-up and shakedown of the newlyinstalled desulfurization equipment. The Agency states that it conducted a lead time analysis and 

spoke with refiners to determine the amount of time that a typical refiner would take to complete 

renovations and meet the 10 ppm sulfur standard. EPA has proposed that a lead time of three 
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years is sufficient. The details of the Agency analysis are set out in Table V-3 — ‘Anticipated 

Compliance Timelines.’

Irving Oil has reviewed EPA’s information on ‘lead times’ and believes that it is overly 

optimistic. Also, some of the data on which the determination was made are now out of date due 

to major changes that are occurring in the petroleum industry. The following are several 

significant reasons why a three-year lead time is insufficient: 

1. Those companies that license the technology to desulfurize motor gasoline have limited 

resources and likely would be unable to support many simultaneous scoping studies and process 

designs. Thus, some refiners would not be able to begin these activities as early as needed to 

support a three-year lead time.

2. Irving Oil agrees with EPA’s assessment that most refiners would revamp existing FCC 

gasoline post-treaters rather than constructing grassroots units. However, Irving Oil has often 

found that revamping units, particularly during the early project phases (the scoping study and 

process design) is more complex and time consuming than building and installing an entirely 

new, grassroots unit. Therefore, EPA’s assumption that refiners can revamp existing units more 

rapidly is not supported by Irving Oil’s many years of experience. 

3. EPA has indicated that some of the initial phases of the revamping project can overlap, 

thereby saving additional time. Again, this assumption is contrary to Irving Oil’s experience and 

belief. Irving Oil has found that the process design phase cannot be started until after the scoping 

study is complete. Thus, it is more reasonable to assume that the time needed to make the 

appropriate changes to the refinery would be the same for both a revamping of units and the 

installation of new units. 

4. The EPA believes that there would be sufficient resources (technology licensors, engineering 

and construction services, skilled laborers, and equipment) available to the refining industry. 

However, EPA must recognize that the U.S is undergoing a domestic petroleum renaissance, and 

demand for these resources in new areas of production such as North Dakota, Montana, and 

Texas is great. Those projects would compete for resources directly with refiners trying to meet 

the EPA three-year time schedule. Shortages of these resources would, therefore, likely inhibit 

the ability of refiners to comply in a timely manner. 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

In the Preamble that accompanied the proposed rule, EPA includes a discussion on the 

“Adequacy of Proposed Refinery Lead Time.” It provides that the Agency has sequenced the 

estimated time to complete scoping studies (6 to 9 months), process design (6 to 9 months), 

permitting (9 months), detailed engineering (6 to 9 months), field construction (6 to 12 months), 

and start-up and shakedown in advance of production (6 to 9 months). In addition, EPA believes 

that there would be substantial overlap among many of these steps. Therefore, the Agency states 

that three years is adequate to implement the required refinery changes, and early credits would 

add some flexibility. This estimate is far too optimistic. It fails to understand the process and 

timing refineries (both domestic and foreign) employ when they make decisions about refinery 

modifications, how financial planning for major modifications is handled, and that longer lead 

times are needed when the regulated community is directed to meet a new standard – not a single 

refiner/importer. 
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First, refiners generally would not undertake to make major modifications until the final 

regulation is issued by EPA. It would not be prudent to begin modifications down one path 

under a proposed rule and subsequently have to alter those modifications if the Agency finalizes 

a rule taking another approach. 

Second, once the rule is adopted, there would be a great demand for consulting and engineering 

firms to assist the refining industry in its efforts to meet this new standard. As EPA is aware, 

there is already a great demand for the services of such firms due to increased production of 

crude oil in PADDs II and III. Thus, some refiners would have to wait for assistance. 

Third, EPA envisions overlapping of some of the enumerated steps such as moving forward with 

design processing while the scoping study is underway. Based on the experience and expertise 

of a number of our Members, we have been told that it is unwise to move forward with design 

processing until the scoping study is complete. Again, substantial man-power, time and money 

could be wasted if design processing anticipates what would emerge from the scoping process. 

Fourth, approval for funding for such major changes is a time-consuming and often difficult 

process. The estimated schedule put forth by EPA does not appear to include the time needed to 

obtain or allocate such funding. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

Rushing implementation undermines the ability of the industry to adequately plan projects, 

secure contractors and equipment at competitive rates, optimize solutions, and align construction 

projects with existing maintenance turn-around schedules. In addition, air permits will be 

necessary at many refineries, and EPA has been challenged in issuing permits in a timely fashion 

(as is discussed in further detail in section VII.F of these comments.) All of these factors will 

tend to increase compliance costs. 

In the proposal, EPA puts forth Table V-3 with a timeline that the Agency believes illustrates the 

time needed to implement the 10 ppm gasoline sulfur requirement at a refinery. 78 Federal 

Register 29925. We disagree with EPA’s suggested timeline. We believe that a more accurate 

amount of time needed to implement major new rules like the 10 ppm gasoline sulfur 

requirement is at least five years. The Tier 2 rules were finalized in February 2000, with 

compliance required to phase in from 2004-06 (with compliance flexibilities that had a more 

meaningful impact, as discussed below). Ultra Low Sulfur Diesel (ULSD) rules were finalized in 

January 2001; with a compliance phase-in period requiring that 15 ppm sulfur diesel constitute 

80% of the highway pool in mid-2006. Compliance lead times need to be longer than these two 

significant rulemakings to reduce sulfur because of new GHG requirements at refiners, and the 

increased reliability of refining equipment has extended refinery turn-around time to 

approximately 5 years. 

Commenter: Marathon Petroleum Company LP (MPC)
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The Agency must extend the implementation date until January 1, 2019 or five years after the 

final rule is issued.

Rushing implementation undermines the ability of the industry to adequately plan projects, 

secure contractors and equipment at competitive rates, optimize solutions, and align construction 

projects with existing maintenance turn-around schedules. All of these factors will tend to 

increase compliance costs. 

In the proposal, EPA puts forth Table V-3 with a timeline that the Agency believes illustrates the 

time needed to implement the 10 ppm gasoline sulfur requirement at a refinery. 78 Federal 

Register 29925. We disagree with EPA’s suggested timeline. We believe that a more accurate 

amount of time needed to implement major new rules like the 10 ppm gasoline sulfur 

requirement is at least five years. The Tier 2 rules were finalized in February 2000, with 

compliance required to phase in from 2004-06 (with compliance flexibilities that had a more 

meaningful impact, as discussed below). Ultra Low Sulfur Diesel (ULSD) rules were finalized in 

January 2001; with a compliance phase-in period requiring that 15 ppm sulfur diesel constitute 

80% of the highway pool in mid-2006. Compliance lead times need to be longer than these two 

significant rulemakings to reduce sulfur because of new GHG requirements at refiners, and the 

increased reliability of refining equipment has extended refinery turn-around time to 

approximately 5 years. These recent changes for refiners add complexities that warrant 

additional Tier 3 compliance lead time. 

Our Response:

Several commenters also stated that we had underestimated the project time lines for 

revamps and installation of grassroots units. Some commenters compared the time required for 

installing units for Tier 3 with previous rulemakings such as the Tier 2 or highway diesel fuel 

rules.

We disagree with comments that we underestimated project time lines for revamps and 

installation of grass root units. As explained in Section V.E. of the preamble to today’s final 

rule, we believe that the situation for Tier 3 is different than previous rulemakings. The 

technologies for complying with Tier 3, which are the same as those used for complying with 

Tier 2, are well known and well proven. Refiners that complied with Tier 2 using FCC naphtha 

desulfurization technologies installed the following units, all of which were grassroot 

installations: Axens Prime G+, CDTech’s CDHydro and CDHDS, UOP’s ISAL, Phillip’s 

(Sinopec’s) S-Zorb and Exxon’s Scanfining. Prior to choosing a technology, refiners needed to 

evaluate each these different technologies and choose among them, all of which were largely 

untested at the time, which required us to provide more lead time for Tier 2. Since it has been 10 

years since the Tier 2 sulfur standard began to be phased in, refiners now have direct experience 

with the installation and operation of these technologies, and the vendor companies that license 

them continue to support their installations onsite. This fact will allow refiners to reach a 

decision very quickly when complying with Tier 3, particularly, because in most cases the 

refiners will solely be revamping the units installed for Tier 2 when complying with Tier 3.
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Based on our discussions with refiners, construction companies, vendor companies and 

from published literature, we estimated the time it takes to revamp existing postreaters and install 

grassroots postreaters. Revamping an existing postreater is expected to require up to two years. 

Installing a grassroots postreater is estimated to require three years.

We believe that the revamping of postreaters could take even less time than 2 years 

because many of the Tier 3 revamps are expected to be very modest (e.g., change out a reboiler 

or heat exchanger). The availability of a more active catalyst and the expanding practice of 

undercutting the FCC naphtha to the distillate pool (which reduces the FCC volume by 15% and 

sulfur content by 50%) permit the existing FCC postreaters to achieve much further sulfur 

control.

Furthermore, we noted at proposal that since EPA held discussions with many refiners in 

2011 about EPA’s plan to pursue additional sulfur control post-Tier 2 (Tier 3), refiners began the 

process of assessing how they would comply. The Tier 3 proposal was delayed for about a year 

and it is our understanding from recent discussions with vendor companies and some refiners 

that many refiners have already completed their scoping studies. By completing their scoping 

studies, refiners have chosen their technologies, and in the case of grassroots units, vendor 

selection as well (refiners with a particular postreater technology in most cases are expected to 

simply revamp the same vendor’s technology, so there is no need to select a vendor). If refiners 

have already completed their scoping studies, we estimate that installation of the revamps or 

grassroots units would be about 3 months shorter than the 2 and 3 years, respectively, than our 

estimated timelines.

These project timelines are reasonable in light of past industry experiences that show 

FCC postreaters being installed in refineries in less time than what we estimate. At the Motiva 

refinery in Port Arthur, TX, a grassroots CDTech postreater was designed, constructed and 

started up in less than 2 years. At two refineries in Germany, two Prime G+ units were designed, 

constructed and started up – one of them in two years, and the other in 18 months. As an 

extreme example, the $3.6 billion dollar, 180 kbbl/day crude oil volume expansion at Marathon’s 

Garyville, LA refinery was designed, constructed and started up in less than 4 years. This single 

project involved the construction of 10 major refinery units. Since these may be best case 

examples, we continue to believe that our construction projections are reasonable.

One commenter stated that our FCC installation timeline did not include the time 

required to obtain funding for the postreater installation. First, most all FCC postreater projects 

are revamps which are relatively inexpensive installations and thus, funding should be relatively 

easy to obtain. Second, funding for design and construction of the FCC postreater installation 

can be obtained when the scoping study is being completed. As discussed in more detail in 

Section V.E.2.b, if a refiner is experiencing financial hardship and is having trouble obtaining the 

necessary funding which leads to a delay in complying with Tier 3, the refiner may apply for an 

extreme circumstances hardship waiver, which is a hardship waiver based on severe economic or 

physical lead time limitations of the refinery to comply with the Tier 3 standards at the start of 

the program. A refiner seeking such hardship relief under this provision must demonstrate 

criteria, and we expect that a refiner would apply for such hardship prior to the start of the Tier 3 
Tier 3 Summary and Analysis of Comments

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program (as a refiner should know during the planning stages if there will be extreme financial 

hardship).

In response to one commenter’s concern about permitting and its impact on completing 

projects, as we discuss in Chapter 5.2, we expect that only a few permits are expected to be 

needed. Because of that, the few refineries needing to file a permit are expected to experience 

construction times about as long as we estimated, and the rest of the refineries, which are not 

expected to file a permit, could experience shorter construction timelines than what we 

estimated.

One commenter noted that we show overlapping time between important elements that 

comprise the planning, design and construction schedule, and commented that the overlap is not 

possible. The commenter stated that one element must be completed before the next one can 

commence. We show overlap between the different elements because some aspects of each 

element can begin before the next element begins. For example, before the scoping study is 

completed, the refiner will initiate the process to set up a contract to begin the process design. 

Also, before the detailed design is completed, the refiner is expected to begin site preparation 

aspect of the construction which may include demolition of nonused equipment and soil testing. 

Finally, the refiner is likely to test the individual pieces of equipment (such as pumps and 

activated valves) before trying to start up the entire unit which is why startup can begin before 

construction is complete. If refiners overlap the different design, construction and plant start up 

elements as depicted, the refinery would be able to meet the grassroots and revamp timelines we 

laid out. As cited above, the very fast FCC postreater installations (CDTech at Port Arthur and 

two German refineries) and very fast Garyville refinery expansion were likely made possible 

because there was overlap between several of the design and construction elements.

While we acknowledge that some refineries may require more time than we have 

assumed to complete their refinery modifications, others would be able to do so with less time. 

If the Tier 3 program were designed in a way that had a firm fixed date for compliance with no 

flexibility, then perhaps the much more conservative assumptions by the commenters would be 

more appropriate, as the worst case refinery situation would be important in determining the 

appropriate lead-time and start date. However, this is not the case here. As described above, the 

program is designed with considerable flexibility. Thus, it is more appropriate to consider more 

typical project timelines when evaluating lead time. Furthermore, the program, with its 

flexibilities, allows nearly 6 years of lead time for the industry to complete their projects, long 

enough for even the worst case project timelines highlighted by the commenters. 

5.2. Refinery GHG Emissions and Air Permitting Interactions (NSR/NSPS/NESHAP)

5.2.1. GHG Emissions and Refineries 

What Commenters Said:

Commenter: Association of Fuel & Petrochemical Manufacturers (AFPM)
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One oil industry commenter said that the new regulations will create conflicts with existing 

regulations and could jeopardize a refiner’s ability to comply with federal formulation 

regulations since modifications to operations may be necessary to make cleaner fuels which 

could trigger greenhouse gas emissions regulations, putting these projects in jeopardy. 

Specifically, this commenter noted that mandating lower sulfur fuels under the Clean Air Act 

will require facilities to install advanced technologies that increase energy use for the 

formulation of increasingly complex motor fuels and this additional energy consumption will 

result in greenhouse gases and other emissions. Therefore, the proposed gasoline sulfur reduction 

standard will increase the carbon footprint at refineries.

Our Response: 

EPA acknowledges that reducing sulfur from gasoline will result in a small increase in 

CO2 emissions associated with higher energy use required in the process of removing sulfur 

within the refinery. As an extension of our refinery-by-refinery cost modeling described in the 

Preamble, Section VII.B., we calculated the CO2 emission impacts of Tier 3 gasoline sulfur 

control. We estimated refinery-specific changes in process energy and then applied emission 

factors that correspond to those changes, on a refinery-by-refinery basis. As described in 

Chapter 4.5 of the RIA, the results showed an increase of up to 1.9 MMTCO2e in 2018 and 1.6 

MMTCO2e in 2030 for all U.S. refineries complying with the lower sulfur standards assuming 

that the sulfur standards are fully phased-in. In 2018, the combined impact of CH4 and N2O 

emission reductions from the vehicles and CO2 emission increases from the refineries shows a 

slight net decrease on a CO2 equivalent basis. While still small, this net decrease grows to a 

range between 2.5 to 2.7 MMTCO2e by 2030. 

In our updated analysis for the final rule, we adjusted our refinery-by refinery analysis to 

reflect the existence of a nationwide average, banking, and trading (ABT) program and refined 

our estimates regarding the physical and operational changes that will be required at each 

refinery (as described in the final RIA). The modifications at a given refinery could include 

revamps to existing FCC pre- or post-treatment unit(s) or the installation of a new grassroots 

post-treatment unit for sulfur reduction. Based on the updated projections of refinery-specific 

changes, we re-estimated the increased demand for energy (i.e., fuel to generate process heat, 

steam, and electricity), hydrogen, and sulfur recovery associated with meeting the final Tier 3 

standards. Having received no comments suggesting that they should be changed, we re-applied 

the representative industry emission factors for NAAQS pollutants, their precursors, and GHGs 

for each emitting process and combined them with estimates of incremental activity to estimate 

the emissions changes at each equipment unit (or group of similar units) at each refinery. 

We found that under the high case (worst case scenario), nine refineries appeared likely 

to have significant emissions increases for one or more pollutants and thus would trigger major 

NSR. This estimate equates to approximately eight percent of the 108 refineries projected to sell 

gasoline that will be subject to the Tier 3 standards. Of these nine refineries, we predicted that 

three refineries would need major source permits for NAAQS-related pollutants and their 

precursors (PSD and/or Nonattainment NSR) and for GHGs, while six refineries would need 

PSD permits to address GHG emissions. This number could be lower if those refineries apply 
Tier 3 Summary and Analysis of Comments

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pollution controls, such as SCR for NOX, to sufficiently reduce the emissions increases to levels 

that are below the applicable pollutant significance level, or if the refineries can achieve 

emissions reductions elsewhere at the facility to “net out” of major NSR. 

5.2.2. Issuing Permits

What Commenters Said:

Commenters: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Concerned Citizens Around Murphy; Marathon 

Petroleum Company LP (MPC)

Several oil industry commenters stated that EPA needed to issue permits expeditiously and that 

EPA should adopt the recommendations offered by the Clean Air Act Advisory Committee 

(CAAAC) in the September 2012 report from the Committee’s GHG Permit Streamlining 

Workgroup.

One citizens’ organization commented that clean fuels are an essential part of the Ozone and 

particulate matter solutions. However, many of our fenceline communities do not have 

appropriate monitoring for the 2010 sulfur dioxide ambient air standards. Extra air monitoring 

could ensure the air permit limits are maintained, and air monitoring may even help the refineries 

become more efficient.

Our Response:

EPA is continuing to assess possible approaches to streamlining GHG permitting, 

including those offered in the referenced CAAAC report. As discussed below in Chapter 5.2.2, 

EPA believes that the permits that may be required as a result of the Tier 3 fuel sulfur standards 

will be issued in a timely manner.

EPA is planning to propose a rule soon that will describe requirements for air agencies to 

characterize sulfur dioxide concentrations through ambient monitoring or air quality modeling 

techniques in targeted areas around the country in which the largest sources of emissions are 

located. The air quality information collected by the air agencies will then be used to inform 

future rounds of area designations under the Clean Air Act. The rule will reference appropriate 

guidance on monitoring and modeling techniques, and it will include timelines for air agencies to 

conduct the required analyses. Comments regarding which sources should be subject to this 

requirement will be welcome as part of that rulemaking.

5.2.3 GHG Permitting

What Commenters Said:

Commenters: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)
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Several oil industry commenters cited recent EPA-provided information on how many GHG 

permits have been issued by EPA and other permitting authorities since the GHG permitting 

requirement became effective in January 2011. These commenters stated that the small number 

of permits issued brings into question whether EPA’s forecast of how quickly GHG permits will 

be issued when needed in connection with the Tier 3 fuel program is realistic.

Several oil industry commenters also noted that if the emissions thresholds that trigger 

permitting for GHG are lowered from the values assumed in EPA’s preliminary assessment of 

permitting implications, the number of refineries that would need GHG permits could be higher 

than estimated in that assessment.

Our Response:

The commenters have cited EPA statements about the number of permits issued, without 

the context of when they were found to be complete. While some permits may have taken longer 

than 12 months to be issued once they were complete during this start-up period of the GHG 

permitting program, EPA continues to believe that in the future time frame in which a small 

number of refineries will be seeking GHG permits, those permits can be issued in a timely 

manner that will assure compliance with the requirements of the final Tier 3 fuel program. The 

experience gained by permitting agencies and the processing approaches developed during the 

start-up period should allow more expeditious processing in the future. Many of the permit 

applications cited by the commenters as not having reached the point of the final permit having 

been issued (as of the May 2012 date of the EPA-provided information) were for sources in 

Texas, where EPA has been the permitting authority for GHG. EPA has recently proposed to 

approve Texas’ plan for assuming the role of that authority (79 FR 9123, February 18, 2014), 

with a final action expected around the middle of 2014. For permits to refineries in Texas issued 

by Texas during the implementation of the Tier 3 program, a number of requirements in federal 

laws that are applicable to EPA permitting actions will no longer apply, for example the federal 

Endangered Species Act. It should be possible both for sources to prepare complete applications 

more expeditiously since they will not need to include all the information needed to ensure 

compliance with these federal laws, and for the Texas permitting authority to review permit 

applications in less time than has been the case for EPA. Since May 2012, EPA has also 

proposed or taken final action to transfer GHG permitting authority to Arkansas, Florida, Idaho,

Kentucky, Clark County in Nevada and Wyoming. In addition to those states for which we 

approved GHG PSD authority, EPA has approved PSD authority (including GHG) to the 

following air pollution districts in California: Eastern Kern, Imperial County, Placer County, San 

Joaquin Valley Unified, and Yolo-Solano. EPA has also approved the South Coast Air Quality 

Management District’s ability to issue GHG PSD Permits. 

Regarding the comments that the number of refiners needing GHG permits could be 

higher than estimated if the thresholds are lowered, EPA finalized GHG thresholds for Step 3 of 

the GHG permitting program that are the same as in Steps 1 and 2 on July 12, 2012. These are 

the thresholds assumed in the updated assessment of permitting implications of the final Tier 3 

fuel program. EPA will complete a further rulemaking by April 2016 to establish permanent 
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thresholds (the Step 4 rulemaking). In the Step 4 rulemaking, EPA may consider the possible 

need for the permanent thresholds to be phased in over some period after that final rule.

5.2.4. New Source Review

What Commenters Said: 

Commenters: Countrymark; Environmental Defense Fund (EDF); Northeast States for 

Coordinated Air Use Management (NESCAUM); Sierra Club; Small Business 

Refiners

A number of refiners requested that the final rule explicitly affirm that any investment required 

for compliance with Tier 3 requirements not be subject to NSR permitting review, provided that 

capacity is not increased by more than 10 percent of prior capacity.

Two environmental groups commented that they supported EPA’s not allowing vehicle emission 

reductions to be used as part of “netting out” under the NSR program, while one state air board 

supported the use of vehicle emission reductions for purposes of “netting out” under the NSR 

program.

An environmental group recommended that, to the extent that EPA moves forward with 

developing streamlining options for NSR, EPA must reach out to all stakeholders to identify 

methods that are wholly consistent with the CAA and the goals of the PSD program. Any 

committee of EPA employees with refinery expertise that oversees streamlining for permits 

related to the Tier 3 fuels program must be shielded against industry lobby interests and any 

conflicts of interest in implementing NSR regulations.

Our Response: 

EPA believes such a blanket exemption based on a percentage increase in refinery 

capacity would not be consistent with CAA requirements. Under the Clean Air Act as 

interpreted by the courts, new source review applies to any physical modification that causes 

more than a de minimis net emissions increase. (See New York v. EPA, 413 F.3d 3 (D.C. Cir. 

2005.) The final Tier 3 rule does not include such an exemption.

The final rule does not include any provision to allow the use of vehicle emission 

reductions for purposes of “netting out” of the NSR program. EPA believes that the use of 

vehicle emissions reductions for netting purposes is not permitted by the NSR regulations, since 

the creditable emissions reductions used for netting purposes must result from reductions 

occurring at the modified source. For example, the definition of net emissions increase in 40 

CFR 52.21(b)(3)(i) includes only increases and decreases occurring “at the source”. We believe 

this provision in the NSR rules is consistent with the CAA. With regard to the commenter 

supporting the use of “netting out,” the commenter did not provide any grounds for concluding 

that allowing the use of vehicle emission reductions for netting out purposes would be consistent 

with the CAA.
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Regarding the comment on streamlining, EPA has concluded that only a small number of 

refineries appear to have the potential of triggering major source permitting as a result of 

modifications needed to meet the Tier 3 fuel program. Furthermore, given the flexibilities 

provided by the final program in terms of when modifications must be in place in order to 

achieve compliance, even the limited number of permits will likely be spread out over a period 

of time. There were no industry comments that demonstrated a specific reason for concern about 

permitting implications on a broad scale. Therefore, EPA intends to address any permitting 

complications that do arise on a case-by-case basis with the appropriate EPA Regional Office in 

the lead, rather than convene an agency-wide committee of experts.

5.2.5. GHG Emissions and Offsets

What Commenters Said: 

Commenters: American Petroleum Institute (API); Association of Fuel & Petrochemical 

Manufacturers (AFPM)

One commenter stated that since EPA claims that the refinery GHG emissions will be offset by 

other parts of this rule, EPA needs to establish a methodology to allow each refinery that 

participates in Tier 3 to increase its future GHG baselines for any permitting purposes by the 

amount that the Tier 3 final regulations will increase its GHG emissions. 

Our Response:

EPA interprets this comment to be a recommendation that refineries making GHGincreasing modifications in order to comply with new sulfur limits should, for PSD permitting 

purposes, be considered not to be increasing their GHG emissions since Tier 3 standards will 

result in GHG-reducing emissions of N2O and CH4 from light-duty vehicles and trucks. EPA 

disagrees with this suggested approach and the final rule does not include changes in the 

definition of baseline GHG emissions for refineries. The definition of baseline emissions for 

PSD purposes is contained in the PSD regulations, which EPA did not propose to amend, or take 

comment on, in this action. Nor did EPA propose any changes to the definition of stationary 

source that would allow a stationary source to take credit for reductions occurring at offsite 

mobile sources. Moreover, EPA’s analysis of the possible permitting implications of the final 

rule requirements for sulfur content indicated that the need for GHG permits will be limited to 

relatively few refineries, and that these refineries and the relevant permitting authorities will be 

able to issue the necessary permits in a timely manner. Also, we expect that GHG Best Available 

Control Technology (BACT) requirements determined for this permitting of GHG emissions will 

generally be the use of energy efficiency measures that refineries will naturally include in their 

modifications anyway for economic reasons.

5.2.6. Flexibilities
Tier 3 Summary and Analysis of Comments

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What Commenter Said:

Commenters: Natural Resources Defense Council (NRDC)

An environmental group commented that due to the absence in the proposed Tier 3 rulemaking 

of any changes to EPA’s permitting regulations, it would be unwarranted for the final action to 

create new flexibilities. The same commenter indicated its support for EPA efforts to help 

ensure that air permits meeting current permitting requirements are issued in a timely manner. 

Another environmental group also commented in opposition to any scheme to side-step any NSR 

requirements. This commenter expressed particular concern about streamlining options that 

might allow refineries to avoid the applicability of major NSR entirely and about any reliance on 

presumptive BACT limits or general permits.

Our Response:

The final rule does not establish any new flexibilities or exceptions to current permitting 

regulations. On an ongoing basis, EPA continues to consider ways to streamline the permitting 

process consistent with CAA requirements and goals.

5.3. Standards for Denatured Fuel Ethanol and Other Oxygenates

5.3.1. Sulfur Standard

What Commenters Said:

Commenter: American Coalition for Ethanol (ACE)

ACE supports 10 ppm sulfur for denatured fuel ethanol as developed by ASTM with input from 

oil companies and automakers. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

In the event that EPA finalizes a more stringent average sulfur standard, API and AFPM support 

EPA’s proposal that producers of fuel ethanol, or other oxygenates, be required to also meet a 

10-ppm sulfur cap. 

In the event that EPA finalizes a more stringent 10-ppm refinery average sulfur standard, API 

and AFPM support EPA’s proposal within new §80.1610(a)(1) that producers of denatured fuel 

ethanol (DFE), or other oxygenates, for use by oxygenate blenders be required to meet a 10-ppm 

sulfur cap, as determined in accordance with the test requirements for refiners and importers.

Commenter: Chevron Products Company
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Standards for Denatured Fuel Ethanol and Other Oxygenates: We support the Agency’s proposal 

that manufacturers of Denatured Fuel Ethanol (DFE) for use by oxygenate blenders would be 

required to meet a 10-ppm sulfur cap. We note the Agency’s comments that the California 

regulations (Title 13, Section 2262.9) already require this maximum level of sulfur (among other 

specifications) and that manufacturers of DFE have already been producing to the California 

specification because of logistical difficulties in segregating ethanol destined for California from 

other destinations. We, therefore, concur with the Agency’s view that implementation of a 10-

ppm sulfur cap would not result in an additional burden on the ethanol industry. 

Commenter: Growth Energy

EPA should change the proposed DFE 10 ppm sulfur cap to a 10 ppm sulfur average to put DFE 

on a level playing field with unleaded.

In the past, EPA has regulated DFE with a sulfur limit that “reflects that 30-ppm refinery 

average.” EPA says that “consistent with” its new 10-ppm refinery sulfur standard, EPA 

proposes “that manufacturers of DFE for use by oxygenate blenders would be required to meet a 

10-ppm sulfur cap.”

If DFE will have the same batch testing and registration requirements as gasoline, requiring a 10 

ppm sulfur cap versus an average could disadvantage DFE versus gasoline, which can generate 

and profit from sulfur credits. DFE having the same sulfur limits as gasoline, along with a 

compliant petroleum blendstock, will result in ethanol blends having a sulfur limit that is 

identical to the proposed finished gasoline specifications. 

Furthermore, if the burden of implementing batch testing and reporting is imposed on ethanol 

producers, they should be allowed to generate sulfur credits. EPA states that “While certain 

batches of ethanol could theoretically be low enough in sulfur to generate credits, it is our desire 

to limit credit generation to companies required to comply with the proposed Tier 3 sulfur 

standards, i.e., refiners and importers.’

Growth Energy believes that ethanol producers should not be required to undertake batch testing; 

however, if DFE producers are required to complete the batch testing, reporting, and record 

keeping on DFE similar to refiner requirements on gasoline, they should have the same ability to 

generate or use credits. 

EPA mistakenly states that “since many refiners currently comply with our standards taking into 

consideration the fuel property changes expected as a result of downstream ethanol blending, 

providing ethanol blenders with sulfur credit would result in double counting the effects of 

ethanol.” However, double counting would not result if refiners are assuming that DFE has a 

sulfur level of 10 ppm. Credits would only be generated at levels that are below this 10 ppm 

level. 

EPA attempts to further reject ethanol generating sulfur credits by stating that “Over compliance 

with the per-gallon cap would not be a valid basis for credit generation, as you would expect that 

in all cases the DFE would be below the cap. To allow credit generation, we would need to 
Tier 3 Summary and Analysis of Comments

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propose an additional annual average sulfur standard for DFE at some level below 10 ppm, and 

allow credits to be generated for over compliance with that standard.” Ethanol producers should 

have the same ability to generate credits if they have the same testing and reporting standards. In 

order to remain price-competitive with gasoline, ethanol should be allowed to generate credits in 

a similar manner as gasoline. Furthermore, such credit trading could allow ethanol producers to 

offset the cost of [new] DFE testing and reporting requirements. 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

Current gasoline requirements include the prohibition on blending gasoline with denatured 

ethanol that has a sulfur content higher than 30 ppm. EPA is proposing to amend that standard 

and not allow blending with denatured ethanol that has sulfur content higher than 10 ppm. The 

Association supports this proposed change. If denatured ethanol contained 30 ppm sulfur, it 

could be difficult for refiners and importers to meet the annual average standard of 10 ppm. 

Recommendation: The Association recommends that EPA adopt its proposal to lower the sulfur 

content of denatured ethanol. Reduce the sulfur content of denatured ethanol to 10 ppm to 

facilitate meeting the proposed Tier 3 standard.

Commenter: Irving Oil Terminals Inc.

Under current gasoline regulations, gasoline may not be blended with denatured fuel ethanol that 

has a sulfur content greater than 30 ppm. Under the Tier 3 proposal, the ethanol sulfur content 

would be reduced to 10 ppm consistent with the proposed standard for gasoline. Irving Oil 

supports this proposed amendment and believes that such a reduction would be essential if the 10 

ppm sulfur annual average is adopted for gasoline. If the sulfur standard for denatured fuel 

ethanol were left at its current level of 30 ppm, refiners would have to further assess and 

determine if greater capital investments would have to be made to their FCC gasoline post-treater 

units or additional investments be made to adjust and lower the sulfur content of other gasoline 

blending streams to prevent violation of the ultimate 10 ppm annual average standard. 

Commenter: Marathon Petroleum Company LP (MPC)

In the event that EPA finalizes a more stringent 10-ppm refinery average sulfur standard, MPC 

supports EPA’s proposal within new §80.1610(a)(1) that producers of denatured fuel ethanol 

(DFE), or other oxygenates, for use by oxygenate blenders be required to meet a 10-ppm sulfur 

cap, as determined in accordance with the test requirements for refiners and importers. 

Commenter: National Corn Growers Association (NCGA)

EPA proposed that manufacturers of DFE for use by oxygenate blenders meet a 10 ppm sulfur 

cap, and that only natural gasoline, gasoline, and gasoline blendstocks for oxygenate blending 

(BOB) be used as ethanol denaturants. NCGA supports EPA’s proposal for DFE standards. We 

believe it would be unnecessary and burdensome to adopt California’s additional specifications 

for DFE. 
Chapter 5: Tier 3 Fuel Sulfur Program

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Commenter: New York State Department of Environmental Conservation

The proposed limits on the sulfur content of blending streams such as denatured fuel ethanol are 

necessary to ensure that the program benefits are actually realized.

Commenter: POET, LLC

EPA should change the proposed DFE 10 ppm sulfur cap to a 10 ppm sulfur average to put DFE 

on a level playing field with unleaded. 

EPA has in the past regulated DFE with a sulfur limit that ‘reflects the current 30-ppm refinery 

average. (67) EPA says that ‘consistent with’ its new 10-ppm refinery sulfur standard, EPA 

proposes ‘that manufacturers of DFE for use by oxygenate blenders would be required to meet a 

10-ppm sulfur cap. (68) EPA also proposes that DFE manufacturers would be subject to batch 

testing (including batch volume, sulfur content, and denaturant concentration as applicable). (69) 

While the final ethanol blends (e.g., E30, E85, or some other blend ratio from E16 to E85) would 

not necessarily be subject to batch testing (under the Blender Option, below), EPA here proposes 

that the DFE would be tested. 

If DFE will have the same batch testing and registration requirements as gasoline, requiring a 10 

ppm sulfur cap versus an average could disadvantage DFE versus gasoline which can generate 

and profit from sulfur credits. DFE having the same sulfur limits as gasoline, along with a 

compliant petroleum blendstock, will result in ethanol blends (whether MLEBs or HLEBs) 

having a sulfur limit that is identical to the proposed finished gasoline specifications. 

Furthermore, if the burden of implementing batch testing and reporting is imposed on DFE 

producers, they should be allowed to generate sulfur credits. EPA states that ‘While certain 

batches of ethanol could theoretically be low enough in sulfur to generate credits, it is our desire 

to limit credit generation to companies required to comply with the proposed Tier 3 sulfur 

standards, i.e., refiners and importers.’ (70) If DFE producers are required to complete the batch 

testing, reporting, and record keeping on DFE similar to refiner requirements on gasoline, they 

should have the same ability to generate or use credits. 

EPA mistakenly states that ‘since many refiners currently comply with our standards taking into 

consideration the fuel property changes expected as a result of downstream ethanol blending, 

providing ethanol blenders with sulfur credit would result in double counting the effects of 

ethanol.’ (71) However, double counting would not result if refiners are assuming that DFE has a 

sulfur level of 10 ppm. Credits would only be generated at levels that are below this 10 ppm 

level. 

EPA attempts to further reject ethanol generating sulfur credits by stating that ‘Over compliance 

with the per-gallon cap would not be a valid basis for credit generation, as you would expect that 

in all cases the DFE would be below the cap. To allow credit generation, we would need to 

propose an additional annual average sulfur standard for DFE at some level below 10 ppm, and 

allow credits to be generated for over compliance with that standard.’ (72) Ethanol producers 

should have the same ability as refiners to generate credits if they have the same testing and 
Tier 3 Summary and Analysis of Comments

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reporting standards. In order to remain price-competitive with gasoline, ethanol should be 

allowed to generate credits in a similar manner as gasoline. Furthermore, such credit trading 

could allow ethanol producers to offset the cost of new DFE testing and reporting requirements. 

Commenter: Renewable Fuels Association (RFA)

This proposed rulemaking adds the regulatory burden of a 10 ppm sulfur maximum on a batch 

basis for Denatured Fuel Ethanol (DFE). However, DFE does not have a sulfur issue. The 

hydrocarbon denaturant is typically the sole source of sulfur in DFE. 

Although current gasoline requirements include the prohibition on blending gasoline with DFE 

that has sulfur content higher than 30 ppm, the State of California has long required that DFE 

meet a maximum 10 ppm sulfur content standard. In 2002, RFA conducted an industry survey 

that demonstrated DFE manufacturers were meeting the new California requirement of 10 ppm 

sulfur content. Since then, RFA has recommended to the ethanol industry that all DFE meet this 

California requirement and all indications are that ethanol producers are adhering to this 

recommendation. 

Because DFE already meets the proposed 10 ppm sulfur standard in nearly all cases, EPA 

believes that the implementation of a 10-ppm sulfur cap for DFE would not result in an increased 

regulatory or administrative burden for ethanol producers. We agree that there would be no new 

burden in terms of ensuring DFE complies with the 10 ppm maximum sulfur limit. 

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

Producers of denatured fuel ethanol and other oxygenates also would be required to meet the 

annual average of 10 ppm sulfur. 

Our Response:

The Tier 2 gasoline requirements include the prohibition on blending gasoline with DFE

that has sulfur content higher than 30 ppm.3 This requirement reflects the 30 ppm refinery 

gasoline average sulfur requirement under the Tier 2 program. Since the sulfur content of DFE 

was typically below 30 ppm, addition of DFE to gasoline would typically lower the sulfur 

content of the mixture relative to gasoline. Hence, additional regulatory requirements regarding 

the sulfur content of DFE were not necessary under the Tier 2 program to ensure DFE addition 

did not increase gasoline sulfur levels. With the introduction of the 10 ppm average sulfur

standard for gasoline under the Tier 3 program, additional control of DFE sulfur content is 

needed to ensure that that the addition of DFE to gasoline does not result in an increased sulfur 

level for the mixture. Hence, consistent with the approach under the Tier 2 program and the 10

ppm refinery average sulfur standard for gasoline finalized under the Tier 3 program, the Tier 3 

FRM requires that producers of DFE and other oxygenates for use by oxygenate blenders meet a 

10 ppm sulfur cap beginning January 1, 2017. 

 

3

40 CFR 80.385(e).
Chapter 5: Tier 3 Fuel Sulfur Program

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In demonstrating compliance with the Tier 3 program’s 10 ppm average gasoline sulfur 

standard, gasoline refiners and importers may adjust the sulfur levels in the gasoline and BOBs 

that they produce/import to account for the downstream addition of ethanol.4 Therefore, the 

sulfur level of DFE has direct effect on the extent of the desulfurization measures that a 

refiner/importer will have to undertake to comply with the gasoline sulfur standards finalized 

today.

 

EPA believes that requiring DFE to comply with a 10 ppm sulfur cap is the most 

appropriate means of ensuring that finished gasoline blends attain the sulfur control goals of the 

Tier 3 program. Controlling the sulfur content of DFE can be readily accomplished by limiting 

the sulfur content of the denaturant that is used. Neat ethanol produced with standard quality 

control practices should have negligible sulfur content. Denaturants with sufficiently low-sulfur 

content to facilitate compliance with the 10 ppm sulfur cap for DFE are widely available. 

Allowing DFE to exceed 10 ppm would result in the use of higher-sulfur denaturants, thereby 

increasing gasoline refiner capital costs to install desulfurization equipment. As discussed in 

Chapter 5.5.1 of this Summary and Analysis of Comments document, there are several reasons 

why we do not believe that it is appropriate to expand the ABT provisions to include ethanol 

producers and importers. Furthermore, as discussed in Section V.G.4. of the preamble to the 

Tier 3 FRM and Chapter 5.3.3 of this Summary and Analysis of Comments document, sulfur 

testing on each batch of DFE will not be required provided that the DFE producer or importer 

demonstrates compliance with the 10 ppm sulfur cap for DFE with volumetric blending records, 

whereas an average standard would require testing of every batch. We anticipate that DFE 

producers and importers will typically choose to demonstrate compliance with the 10 ppm sulfur 

cap using volumetric blending records rather than per-batch sulfur testing. Therefore, we do not 

anticipate that DFE producers and importers will need to install additional sulfur testing 

equipment as a result of the Tier 3 final rule. The registration, reporting, and recordkeeping 

requirements for DFE producers that we are finalizing will not necessitate substantial capital 

investments. Hence, there is no need to extend the flexibility of meeting an annual average 

sulfur standard and participation in the ABT program to ethanol producers and importers to help 

facilitate their compliance as exists for gasoline refiners. 

5.3.2. Requirements to Address the Potential Emissions Effects of Fuel Parameters Other 

than Sulfur in DFE

5.3.2.1. Specifications on the Benzene, Olefins, and Aromatics Content of DFE and 

the Denaturants Used in the Manufacture of DFE

What Commenters Said:

Commenter: American Coalition for Ethanol (ACE)

 

4 Accounting for the effect of oxygenate added downstream of the refinery or import facility in demonstrating 

compliance with the average gasoline sulfur standard is addressed in regulations finalized today at §80.1603(d). See 

Section V.C. in the preamble to the Tier 3 FRM regarding the sulfur level in DFE that must be used by refiners and 

importers in making this compliance determination. 
Tier 3 Summary and Analysis of Comments

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Standards for Denatured Fuel Ethanol: Again, in keeping with EPA’s desire to test vehicles on 

fuel available in the marketplace, we believe it is unnecessary to adopt California’s specialized 

requirements. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

We agree EPA should not set limits for benzene, olefins, and aromatics content of ethanol. 

API and AFPM agree with EPA’s plans to not propose limits for benzene, olefins, and aromatics 

content of DFE. We agree that ASTM International Specification D4806 in combination with 

TTB denaturant requirements and low denaturant concentrations (typically 2 volume 

percent) would limit the benzene, olefins, and aromatics content of DFE to very low levels. We 

also do not support the adoption of the State of California’s benzene, olefin and aromatics 

specifications for DFE. Limits imposed by the California Air Resources Board (CARB) address 

concerns specific to California, and hence should not be applied to the remainder of the country. 

Commenter: Chevron Products Company

The Agency also requests comment on whether it should adopt California’s limits on benzene, 

olefins and aromatics for DFE. The Agency is not proposing any limits on these parameters. Our 

view is that the Agency should adopt California’s requirements in their entirety. Since many 

ethanol producers are already manufacturing to a single national ‘specification’ to meet the 

California requirements, such action by the Agency would not impose any additional burden on 

them while offering the benefit of formalizing the ‘de facto’ application of a single DFE 

specification nationwide. 

Many of the questions that the Agency seeks input on, can be simply resolved via the adoption of 

the California DFE specifications, including whether additional denaturants should be allowed 

(beyond, natural gasoline, gasoline, and gasoline blendstocks) and the range of allowable 

denaturant content.

Commenter: Growth Energy

It is unnecessary to establish benzene, aromatics and olefin limits on DFE.

The Proposed Rule states that limiting denaturants (e.g., to natural gasoline, gasoline, and BOBs 

“along with Internal Revenue Service ethanol denaturant requirements would limit benzene, 

olefins, and aromatics content of DFE to very low levels.” Growth Energy agrees with EPA’s 

“not proposing any limits on these parameters in DFE.” 

We further agree that the California DFE standards for benzene, aromatics, and olefins not be 

adopted. Not only would this impose a testing and record keeping burden on DFE producers, but 

it would not be meaningful given that there are no aromatics or olefin limitations for gasoline 

components (outside of base and certification fuel standards). (10) 
Chapter 5: Tier 3 Fuel Sulfur Program

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10 The California regulations are also inappropriately stringent. California requires ethanol benzene 

levels to be 0.06 percent or lower and the denaturant to contain 1.1 percent benzene maximum. This 

benzene level in the DFE is 10 percent of the 0.62 percent benzene limit for unleaded gasoline. Ethanol 

should not bear a burden so strict compared to gasoline. Also, many natural gasoline streams do not meet 

this 1.1 percent benzene specification, as the benzene content is related to the natural gasoline source 

stream and processing. Many locations need to use denaturants with non-California-compliant benzene 

content. Using California benzene limits would increase costs as many companies would be forced to use

far more expensive denaturants.

Commenter: Marathon Petroleum Company LP (MPC)

MPC agrees with EPA’s plans to not propose limits for benzene, olefins, and aromatics content 

of DFE. We agree that ASTM International Specification D4806 in combination with TTB 

denaturant requirements and low denaturant concentrations (typically 2 volume percent) would 

limit the benzene, olefins, and aromatics content of DFE to very low levels. We also do not 

support the adoption of the State of California’s benzene, olefin and aromatics specifications for 

DFE. Limits imposed by the California Air Resources Board (CARB) address concerns specific 

to California, and hence should not be applied to the remainder of the country. 

Commenter: National Corn Growers Association (NCGA)

Standards for Denatured Fuel Ethanol (DFE) 

NCGA supports EPA’s proposal for DFE standards. We believe it would be unnecessary and 

burdensome to adopt California’s additional specifications for DFE. 

Commenter: POET, LLC

POET agrees with EPA that it is unnecessary to establish benzene, aromatics and olefin limits on 

DFE. 

The Proposed Rule states that limiting denaturants (e.g., to natural gasoline, gasoline, and BOBs) 

‘along with Internal Revenue Service ethanol denaturant requirements would limit benzene, 

olefins, and aromatics content of DFE to very low levels.’ (73) POET agrees with EPA’s ‘not 

proposing any limits on these parameters in DFE.’ (74) 

POET further agrees with EPA’s assessment that it should not adopt the California DFE 

standards for benzene, aromatics, and olefins. (75) Not only would this impose a testing and 

record keeping burden on DFE producers, but it would not be meaningful given that there are no 

aromatics or olefin limitations for gasoline components (outside of base and certification fuel 

standards). (76) 

76 - The California regulations are also inappropriately stringent. California requires ethanol benzene 

levels to be 0.06% or lower and the denaturant to contain 1.1% benzene maximum. This benzene level in 

the DFE is 10% of the 0.62% benzene limit for unleaded gasoline. Ethanol should not bear a burden so 

strict compared to gasoline. Also, many natural gasoline streams do not meet this 1.1% benzene 

specification, as the benzene content is related to the natural gasoline source stream and processing. Many 

locations need to use denaturants with non-California-compliant benzene content. Using California 
Tier 3 Summary and Analysis of Comments

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benzene limits would increase costs as many companies would be forced to use far more expensive 

denaturants.

Commenter: Renewable Fuels Association (RFA)

We agree that parametric limits on benzene, olefins, and aromatics in DFE are unnecessary, as 

these substances are typically absent from DFE or are present at extremely low levels as a result 

of denaturing. RFA agrees no redundancy is needed in restricting the benzene, aromatics and 

olefins allowed in denatured fuel ethanol. Benzene, aromatics and olefins found in denatured fuel 

ethanol are strictly a product of the mandatory TTB denaturant addition.

Our Response:

We requested comment on adopting the additional fuel specifications currently in force 

for DFE in the State of California. The California requirements for DFE include maximum 

specifications for benzene, olefins, and aromatics as well as sulfur.5 We believe that limitation 

on denaturant concentration and other requirements for DFE that we are finalizing as described 

in Section V.G. of the Tier 3 final rule preamble, and Chapters 5.3.2.2 and 5.3.2.3 of this 

Summary and Analysis of Comments document, are sufficient to limit the potential emissions 

effects of fuel parameters other than sulfur in DFE at this time. Therefore, we are not finalizing 

benzene, aromatics, and olefins specifications for DFE (or certified ethanol denaturant) at this 

time.

5.3.2.2. Limitations on the Types of Denaturants Used in the Manufacture of DFE

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

API and AFPM do not support limiting the products that can be used as alcohol denaturants, and 

recommend that if EPA must act, the latest version of ASTM International Specification D4806 

should be adopted, and EPA should not further narrow the list of available denaturants. 

API and AFPM do not support EPA’s proposal to restrict the number of available denaturants 

within new §80.1610(a)(3) to gasoline, RBOB, CBOB or natural gas liquids. As EPA points-out 

in the preamble, ASTM International Specification D4806 provides for the use of natural 

gasoline, gasoline blendstocks, and gasoline, as denaturants. Furthermore, the State of California 

also approves the use of gasoline components, as well as natural gasoline and unleaded gasoline, 

as DFE denaturants. Contrary to the preamble, EPA’s proposal does not adopt the same

specification as ASTM D4806 by restricting the scope of available gasoline blendstocks to 

RBOB and CBOB. This narrowing will restrict the potential supply of available denaturants for 

producers of denatured fuel ethanol, which are also required to meet U.S. Department of 

Treasury Alcohol and Tobacco Tax and Trade Bureau (TTB) denaturant requirements and State 

 

5 California Code of Regulations 13 CCR section 2262.9. 
Chapter 5: Tier 3 Fuel Sulfur Program

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of California DFE requirements, when DFE is supplied to California. Although EPA expresses 

concern that denaturant limitations are needed to prevent the use of other components that 

“might adversely impact vehicle emission performance”, data supporting this presumption is not 

presented. API and AFPM believe that with the combination of low denaturant concentrations 

(typically 2 volume percent) and TTB denaturants restrictions, any components of concern 

would be at very low levels and would unlikely impact vehicle emissions performance. For 

simplicity, API and AFPM recommend that if EPA must act, the latest version of ASTM 

International Specification D4806 should be adopted, and EPA should not further narrow the list 

of available denaturants. 

Commenter: Chevron Products Company

Many of the questions that the Agency seeks input on, can be simply resolved via the adoption of 

the California DFE specifications, including whether additional denaturants should be allowed 

(beyond, natural gasoline, gasoline, and gasoline blendstocks) and the range of allowable 

denaturant content. We believe there is sufficient flexibility in the slate of available potential 

denaturants that ethanol producers can utilize while adhering to ASTM D4806 requirements and 

do not see a benefit in broadening the list to include additional materials. The current list 

represents the material that would be most commonly available to ethanol producers and, thus, 

there is little (if any) incremental flexibility in allowing additional ones as potential denaturant 

‘options.’ By the same token, maintaining the list as it currently exists would not present a new 

burden on DFE producers. Our recommendation to the Agency is to simply follow the 

requirements of ASTM in this regard since that is the right technical forum where any proposed 

addition of new denaturants to the specification should be entertained. 

Commenter: Flint Hills Resources, LP (FHR)

In summary, should a more stringent standard be finalized as proposed by EPA, FHR believes 

that other gasoline blendstocks should be allowed to be used as denaturants for DFE. 

Other Gasoline Blendstocks Should be Allowed for Use as Denaturants: FHR does not support 

EPA’s proposal to restrict the number of available denaturants within new §80.1610(a)(3) to only 

gasoline, RBOB, CBOB or natural gas liquids. FHR recommends that if EPA must act, the latest 

version of ASTM Standard Specification D4806 for Denatured Fuel Ethanol (DFE) should be 

adopted, similar to the certification test fuels requirement proposed within §80.177(b)(i). 

As EPA points-out in the preamble, ASTM D4806 provides for the use of natural gasoline, 

gasoline blendstocks or unleaded gasoline, as denaturants. In addition, the State of California 

also approves the use of gasoline components, as well as natural gasoline and unleaded gasoline. 

Contrary to the preamble, EPA’s proposal does not adopt the same specification as ASTM 

D4806 by restricting the scope of available gasoline blendstocks to RBOB and CBOB. This 

narrowing will restrict the potential supply of available denaturants to DFE producers, which 

must also meet U.S. Department of Treasury Alcohol and Tobacco Tax and Trade Bureau (TTB) 

denaturant requirements and State of California DFE requirements, when supplied to California. 

Although EPA expresses concern that denaturant limitations are needed to prevent the use of 

other components that ‘might adversely impact vehicle emission performance’, data supporting 
Tier 3 Summary and Analysis of Comments

5-111

this presumption is not presented. FHR believes that with the combination of low denaturant 

concentrations (typically 2 volume percent) and ASTM D4806 specifications and TTB 

denaturant restrictions, any potential components of concern would be at very low levels and 

would unlikely impact vehicle emissions performance. 

Commenter: Growth Energy

EPA should not limit denaturants to only certified BOBs, certified gasoline and natural gasoline.

EPA limiting denaturants to only certified BOBs, certified gasoline, and natural gasoline would 

unnecessarily reduce denaturant flexibility to prevent use of hydrotreated or refinery produced 

streams that are readily available for gasoline blending or may be available for future use. 

Several denaturants are in use today that do not meet the Alcohol Tobacco Tax and Trade Bureau 

(TTB) or EPA definition of natural gasoline. 

Historically DFE producers have used refinery gasoline blendstocks such as “light straight run” 

and “light naphtha” as denaturants. Removal of this flexibility will increase costs for DFE 

producers. Especially if the sulfur limit for DFE is reduced (i.e., from 30 ppm to 10 ppm) and the 

industry is forced to look at hydrotreated streams not covered in the natural gasoline definitions. 

Importantly, “gasoline blendstocks” and “gasoline blendstocks for oxygenate blending (BOB)” 

are very different and adopting the stricter BOB requirement will have negative economic effects 

on the ethanol industry. 

Instead, EPA should allow a wide range of hydrocarbons for denaturant as long as they meet the 

TTB requirements and the final DFE meets the required benzene and sulfur specifications. The 

TTB requirements at 27 CFR § 19.747 allow for substantial flexibility in denaturant use.28 EPA

should follow similar provisions as the TTB, or incorporate them by cross-reference. 

The proposed definition of NGLs in 40 CFR 80.2 is too restrictive. The definition should not 

include an unduly narrow listing of the types of facilities that produce NGLs and should include, 

for instance, NGLs that may be produced through refineries and hydro-treating. The definition 

should be revised as follows (with additions underlined): “(zzz) Natural Gas Liquids (NGL) 

means the components of natural gas (primarily propane, butane, pentane, hexane, and heptane) 

that are separated from the gas state in the form of liquids in facilities such as a natural gas 

liquids fractionation production facility, or in a natural gas processing plant, or in a natural gas 

pipeline, or refinery or similar facility. The higher temperature boiling components of NGL are 

sometimes also referred to as “natural gasoline”.”

28 In particular, the TTB requirements at The TTB requirements at 27 CFR § 19.747 provide that “If a 

proprietor wishes to use a material to render spirits unfit for beverage use that is not authorized under § 

19.746 or that is not on the published list of materials, the proprietor may submit an application for 

approval to the appropriate TTB officer. The application must include the name of the material and the 

quantity of material that the proprietor proposes to add to each 100 gallons of spirits. The appropriate 

TTB officer may require the proprietor to submit an 8-ounce sample of such material. The proprietor may 

not use any proposed material until the appropriate TTB officer approves its use. Any material that 

impairs the quality of the spirits for fuel use will not be approved. The proprietor must retain as part of the 
Chapter 5: Tier 3 Fuel Sulfur Program

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records available for inspection by appropriate TTB officers any application approved by the appropriate 

TTB officer under this section.”

Commenter: Marathon Petroleum Company LP (MPC)

MPC does not support EPA’s proposal to restrict the number of available denaturants within new 

§80.1610(a)(3) to gasoline, RBOB, CBOB or natural gas liquids. As EPA points-out in the 

preamble, ASTM International Specification D4806 provides for the use of natural gasoline, 

gasoline blendstocks, and gasoline, as denaturants. Furthermore, the State of California also 

approves the use of gasoline components, as well as natural gasoline and unleaded gasoline, as 

DFE denaturants. Contrary to the preamble, EPA’s proposal does not adopt the same 

specification as ASTM D4806 by restricting the scope of available gasoline blendstocks to 

RBOB and CBOB. This narrowing will restrict the potential supply of available denaturants for 

producers of denatured fuel ethanol, which are also required to meet U.S. Department of 

Treasury Alcohol and Tobacco Tax and Trade Bureau (TTB) denaturant requirements and State 

of California DFE requirements, when DFE is supplied to California. Although EPA expresses 

concern that denaturant limitations are needed to prevent the use of other components that 

“might adversely impact vehicle emission performance”, data supporting this presumption is not 

presented. MPC believes that with the combination of low denaturant concentrations (typically 2 

volume percent) and TTB denaturants restrictions, any components of concern would be at very 

low levels and would unlikely impact vehicle emissions performance. For simplicity, MPC 

recommends that if EPA must act, the latest version of ASTM International Specification D4806 

should be adopted, and EPA should not further narrow the list of available denaturants. 

Commenter: National Corn Growers Association (NCGA)

EPA proposed that manufacturers of DFE for use by oxygenate blenders meet a 10 ppm sulfur 

cap, and that only natural gasoline, gasoline, and gasoline blendstocks for oxygenate blending 

(BOB) be used as ethanol denaturants. NCGA supports EPA’s proposal for DFE standards. 

Commenter: POET, LLC

EPA should change the proposed DFE 10 ppm sulfur cap to a 10 ppm sulfur average to put DFE 

on a level playing field with unleaded. 

EPA has in the past regulated DFE with a sulfur limit that ‘reflects the current 30-ppm refinery 

average. (67) EPA says that ‘consistent with’ its new 10-ppm refinery sulfur standard, EPA 

proposes ‘that manufacturers of DFE for use by oxygenate blenders would be required to meet a 

10-ppm sulfur cap. (68) EPA also proposes that DFE manufacturers would be subject to batch 

testing (including batch volume, sulfur content, and denaturant concentration as applicable). (69) 

While the final ethanol blends (e.g., E30, E85, or some other blend ratio from E16 to E85) 

would not necessarily be subject to batch testing (under the Blender Option, below), EPA here 

proposes that the DFE would be tested. 

If DFE will have the same batch testing and registration requirements as gasoline, requiring a 10 

ppm sulfur cap versus an average could disadvantage DFE versus gasoline which can generate 

and profit from sulfur credits. DFE having the same sulfur limits as gasoline, along with a 
Tier 3 Summary and Analysis of Comments

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compliant petroleum blendstock, will result in ethanol blends (whether MLEBs or HLEBs) 

having a sulfur limit that is identical to the proposed finished gasoline specifications. 

Furthermore, if the burden of implementing batch testing and reporting is imposed on DFE 

producers, they should be allowed to generate sulfur credits. EPA states that ‘While certain 

batches of ethanol could theoretically be low enough in sulfur to generate credits, it is our desire 

to limit credit generation to companies required to comply with the proposed Tier 3 sulfur 

standards, i.e., refiners and importers.’ (70) If DFE producers are required to complete the batch 

testing, reporting, and record keeping on DFE similar to refiner requirements on gasoline, they 

should have the same ability to generate or use credits. 

EPA mistakenly states that ‘since many refiners currently comply with our standards taking into 

consideration the fuel property changes expected as a result of downstream ethanol blending, 

providing ethanol blenders with sulfur credit would result in double counting the effects of 

ethanol.’ (71) However, double counting would not result if refiners are assuming that DFE has a 

sulfur level of 10 ppm. Credits would only be generated at levels that are below this 10 ppm 

level. 

EPA attempts to further reject ethanol generating sulfur credits by stating that ‘Over compliance 

with the per-gallon cap would not be a valid basis for credit generation, as you would expect that 

in all cases the DFE would be below the cap. To allow credit generation, we would need to 

propose an additional annual average sulfur standard for DFE at some level below 10 ppm, and 

allow credits to be generated for over compliance with that standard.’ (72) Ethanol producers 

should have the same ability as refiners to generate credits if they have the same testing and 

reporting standards. In order to remain price-competitive with gasoline, ethanol should be 

allowed to generate credits in a similar manner as gasoline. Furthermore, such credit trading 

could allow ethanol producers to offset the cost of new DFE testing and reporting requirements.

POET agrees with EPA that it is unnecessary to establish benzene, aromatics and olefin limits on 

DFE. 

The Proposed Rule states that limiting denaturants (e.g., to natural gasoline, gasoline, and BOBs) 

‘along with Internal Revenue Service ethanol denaturant requirements would limit benzene, 

olefins, and aromatics content of DFE to very low levels.’ (73) POET agrees with EPA’s ‘not 

proposing any limits on these parameters in DFE.’ (74) 

POET further agrees with EPA’s assessment that it should not adopt the California DFE 

standards for benzene, aromatics, and olefins. (75) Not only would this impose a testing and 

record keeping burden on DFE producers, but it would not be meaningful given that there are no 

aromatics or olefin limitations for gasoline components (outside of base and certification fuel 

standards). (76) 

EPA should not limit denaturants to only certified BOBS, certified gasoline, and natural 

gasoline. 
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EPA limiting denaturants to only certified BOBs, certified gasoline, and natural gasoline would 

unnecessarily reduce denaturant flexibility to prevent use of hydrotreated or refinery produced 

streams that are readily available for gasoline blending or may be available for future use. 

Several denaturants are in use today that do not meet the Alcohol Tobacco Tax and Trade Bureau 

(TTB) or EPA definition of natural gasoline. 

Historically DFE producers have used refinery gasoline blendstocks such as ‘light straight run’ 

and ‘light naphtha’ as denaturants. Removal of this flexibility will increase costs for DFE 

producers, especially if the sulfur limit for DFE is reduced (i.e., from 30 ppm to 10 ppm) and the 

industry is forced to look at hydrotreated streams not covered in the natural gasoline definitions. 

Importantly, ‘gasoline blendstocks’ and ‘gasoline blendstocks for oxygenate blending (BOB)’ 

are very different and adopting the stricter BOB requirement will have negative economic effects 

on the ethanol industry. 

Instead, EPA should allow a wide range of hydrocarbons for denaturant as long as they meet the 

TTB requirements and the final DFE meets the required benzene and sulfur specifications. The 

TTB requirements at 27 CFR § 19.747 allow for substantial flexibility in denaturant use. (94) 

EPA should follow similar provisions as the TTB, or incorporate them by cross-reference. 

94 - In particular, the TTB requirements at The TTB requirements at 27 CFR § 19.747 provide that ‘If a 

proprietor wishes to use a material to render spirits unfit for beverage use that is not authorized under § 

19.746 or that is not on the published list of materials, the proprietor may submit an application for 

approval to the appropriate TTB officer. The application must include the name of the material and the 

quantity of material that the proprietor proposes to add to each 100 gallons of spirits. The appropriate 

TTB officer may require the proprietor to submit an 8-ounce sample of such material. The proprietor may 

not use any proposed material until the appropriate TTB officer approves its use. Any material that 

impairs the quality of the spirits for fuel use will not be approved. The proprietor must retain as part of the 

records available for inspection by appropriate TTB officers any application approved by the appropriate 

TTB officer under this section.’

We support the proposal to limit approved denaturants for denatured fuel ethanol to natural 

gasoline, gasoline, and gasoline blendstocks for oxygenate blending (BOBs), however we would 

like to see an option for proposing a new denaturant in the future. 

Commenter: Renewable Fuels Association (RFA)

As for allowable denaturants for denatured fuel ethanol, RFA recommends that EPA recognize 

that the Alcohol and Tobacco Tax and Trade Bureau (TTB) and ASTM carefully restrict the 

allowable materials that can be used as denaturant. RFA also recommends that EPA recognize 

future options for denaturant and allow for the possibility of approving non-hydrocarbon origin 

denaturants. Regulatory schemes such as the California Low Carbon Fuels Standard promote the 

use of low carbon intensity fuels and thus nontraditional denaturants may be needed in the future. 

The ethanol industry should be granted as much flexibility as possible to meet the regulatory 

burden of the denaturing requirements of the TTB while continuously improving ethanol’s 

performance in a spark ignition engine. EPA adding identical effectual denaturant requirements 

is not helpful for the industry or an improvement of air quality. 
Tier 3 Summary and Analysis of Comments

5-115

Commenter: Private Citizen 

Approve denaturants that are non-petroleum based for Alcohol Fuel.

Our Response:

To limit the variability in DFE composition and the associated potential impact on 

vehicle emissions, we proposed to allow the use of only certified gasoline, gasoline blendstocks 

for oxygenate blending (BOBs), and natural gasoline as denaturants. 

The ASTM specification for DFE requires that the only denaturants that can be used are 

gasoline, gasoline blendstocks, and natural gasoline. The State of California incorporated the 

ASTM limits on allowable denaturants into its regulations for DFE by reference.6 Thus, both 

ASTM and the State of California allow the use of gasoline blendstocks other than BOBs as 

denaturants.

While industry standards are typically focused on performance concerns, EPA continues 

to believe that it is appropriate to implement additional controls to address the potential impact 

of fuel components in denaturants other than sulfur on vehicle emissions. In particular, EPA is 

concerned about the use of denaturants that might have a high concentration of benzene or other 

aromatics. We believe that limitation on denaturant concentration and other requirements for 

DFE that we are finalizing as described in Section V.G. of the Tier 3 final rule preamble, and 

Chapter 5.3.2.3 of this Summary and Analysis of Comments document, are sufficient to limit the 

potential emissions effects of fuel parameters other than sulfur in DFE at this time. Therefore, 

we are not finalizing additional controls on the types of denaturants that may be used beyond 

those currently adopted by ASTM and the State of California at this time. In response to 

comments, the Tier 3 FRM includes the requirement that only gasoline, gasoline blendstocks, 

and natural gasoline liquids may be used to denature DFE.7 This requirement is essentially the 

same as the current ASTM and State of California specifications for the type of denaturants that 

may be used. In response to the comment that the proposed definition of natural gasoline liquids 

was too restrictive, we are finalizing the following definition: Natural gas liquids (NGL) means 

the components of natural gas (primarily propane, butane, pentane, hexane, and heptane) that are 

separated from the gas state in the form of liquids in facilities such as a natural gas production 

facility, a gas processing plant, a natural gas pipeline, or a refinery or similar facility. The higher 

temperature boiling components of NGL are sometimes referred to as “natural gasoline”. 

We will continue to monitor the need for additional denaturants, and when appropriate 

EPA may undertake a future rulemaking to evaluate the suitability of additional denaturants and 

consider allowing their use. 

5.3.2.3. Limitation of Denaturant Concentration

 

6 The California Code of Regulations references ASTM D 4806-99 which limits the allowed denaturants to gasoline, 

gasoline components, and natural gasoline.

7

Finished gasoline used as denaturant must be compliant with the applicable EPA requirements. 
Chapter 5: Tier 3 Fuel Sulfur Program

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What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

And, we contend that EPA should not limit the concentration of denaturant to 2%. 

Although EPA expresses concern that denaturant limitations are needed to prevent the use of 

other components that “might adversely impact vehicle emission performance”, data supporting 

this presumption is not presented. API and AFPM believe that with the combination of low 

denaturant concentrations (typically 2 volume percent) and TTB denaturants restrictions, any 

components of concern would be at very low levels and would unlikely impact vehicle emissions 

performance. For simplicity, API and AFPM recommend that if EPA must act, the latest version 

of ASTM International Specification D4806 should be adopted, 

API and AFPM contend that EPA does not need to limit the concentration of denaturant in DFE 

to 2. volume percent within new §80.1610(a)(4). Under the RFS2 regulations, the denaturant 

level of DFE must be limited to 2 volume percent, in order for a producer to generate Renewable 

Identification Numbers (RINs) for each gallon of renewable fuel produced. API and AFPM fully 

understand that DFE producers may decide to produce DFE and not generate RINs. However, 

considering the mandate for RINs, it is very unlikely that a DFE producer would not generate 

RINs. Furthermore, the TTB restricts the denaturant concentration to 5 volume percent, which 

would also limit potential components of concern to very low levels and would unlikely impact 

vehicle emissions performance. As a result, the inclusion of a 2 volume percent requirement 

within the Tier 3 rules is unnecessary. 

API and AFPM contend that EPA does not need to limit the concentration of denaturant in DFE. 

Commenter: Chevron Products Company

Adoption of the California DFE requirements would also address the issue of allowable 

denaturant content since the state's allowable range is 1.96 volume percent minimum to 4.76 

volume percent maximum. The corresponding ASTM (D4806) range is 1.96-5 volume percent. 

We would like the Agency to reconsider its proposal to limit maximum ethanol denaturant 

content to 2 volume percent (even though we understand the Agency's recognizes that this 'limit' 

would actually entail allowing up to 2.5 volume percent denaturant content). We see no value in

introducing yet a more restrictive requirement in the allowable denaturant range and dispute the 

Agency's assertion that this is in any way a facilitation vis-à-vis the RFS2 requirements. The 

minimum value is effectively set by the IRS' requirements at 1.96 volume percent and California 

mirrors that value. The Agency's setting the maximum at 2 volume percent unnecessarily results 

in nearly identical practical maximum and minimum values with only the rounding tolerance 

remaining for some operating flexibility. 

There is no reason that we can see why denaturant content in excess of 2 volume percent cannot 

be 'backed out' of RFS2 RIN calculations and IRS calculations, nor do we consider the process of 

making those adjustments particularly onerous or burdensome. We disagree with the Agency's 
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5-117

assertion that denaturant producer registration and demonstration of compliance with the sulfur, 

aromatics, benzene and olefin content requirements would be necessary if the maximum 

denaturant content is not set at 2 volume percent. In our view, adoption of the California DFE 

requirements in their entirety resolves this issue and obviates the need for such burdensome 

administrative requirements on denaturant producers. 

Commenter: Flint Hills Resources, LP (FHR)

Although EPA expresses concern that denaturant limitations are needed to prevent the use of 

other components that 'might adversely impact vehicle emission performance', data supporting 

this presumption is not presented. FHR believes that with the combination of low denaturant 

concentrations (typically 2 volume percent) and ASTM D4806 specifications and TTB 

denaturant restrictions, any potential components of concern would be at very low levels and 

would unlikely impact vehicle emissions performance. 

Commenter: Growth Energy

EPA should not limit the denaturant content to 2 percent of DFE by volume. Denaturant limits 

exist in other regulations and should not be limited to 2 percent.

EPA notes regarding this issue that it is “proposing to limit the maximum concentration of 

denaturant that can be used in DFE to 2 volume percent.” 

Both ASTM and California allow for up to 5 percent denaturant, and EPA should not adopt a 

more stringent limit. Ethanol producers are strongly incentivized by the RFS to keep denaturant 

under 2 percent.30 However, under certain conditions the flexibility to have a slightly higher 

denaturant content can be very important to ethanol producers. Accordingly, EPA should adopt 

no more stringent than a 5 percent denaturant limit. 

30 The Proposed Rule notes that “Under the RFS2 regulations, if the denaturant level is 2 volume percent or less 

(effectively less than 2.5 volume percent considering rounding) the entire volume of denatured fuel ethanol can be 

used for determining compliance with the RFS2 renewable fuel volume requirements.” Id.

Commenter: Marathon Petroleum Company LP (MPC)

MPC contends that EPA does not need to limit the concentration of denaturant in DFE to 2. 

volume percent within new §80.1610(a)(4). Under the RFS2 regulations, the denaturant level of 

DFE must be limited to 2 volume percent, in order for a producer to generate Renewable 

Identification Numbers (RINs) for each gallon of renewable fuel produced. MPC fully 

understands that DFE producers may decide to produce DFE and not generate RINs. However, 

considering the mandate for RINs, it is very unlikely that a DFE producer would not generate 

RINs. Furthermore, the TTB restricts the denaturant concentration to 5 volume percent, which 

would also limit potential components of concern to very low levels and would unlikely impact 

vehicle emissions performance. As a result, the inclusion of a 2 volume percent requirement 

within the Tier 3 rules is unnecessary. 

Commenter: POET, LLC
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Denaturant limits exist in other regulations and EPA limiting denaturant content to 2% of DFE 

by volume is conflicting and unnecessary. 

EPA notes regarding this issue that it is ‘proposing to limit the maximum concentration of 

denaturant that can be used in DFE to 2 volume percent.’ (95) 

Both ASTM and California allow for up to 5% denaturant, and EPA should not adopt a more 

stringent limit. Ethanol producers are strongly incentivized by the RFS to keep denaturant under 

2%. (96) However, under certain conditions the flexibility to have a slightly higher denaturant 

content can be very important to ethanol producers. Accordingly, EPA should adopt no more 

stringent than a 5% denaturant limit. 

96 - The Proposed Rule notes that ‘Under the RFS2 regulations, if the denaturant level is 2 

volume percent or less (effectively less than 2.5 volume percent considering rounding) the entire 

volume of denatured fuel ethanol can be used for determining compliance with the RFS2 

renewable fuel volume requirements.’ Id.

Commenter: Renewable Fuels Association (RFA)

Several existing regulations and specifications already govern this 2.% volume of denaturant in 

our denatured fuel ethanol (e.g., ASTM, State of California, Alcohol Tax & Trade Bureau 

(TTB)) that confine ethanol producers on their choices of denaturant. 

RFA does not support EPA limiting the amount of denaturant. RFA does not think the EPA 

should restrict the amount of denaturant content in DFE in this regulation. RFA thinks the 

current ASTM specifications for denaturant content are adequate. The DFE specification ASTM 

D4806 allows 5% denaturant content maximum. Further, the industry already has a regulatory 

restriction under the RFS2 for denaturant content; the RFS2 requires that DFE contain no more 

than 2. % denaturant for RIN generation. However, the option to use more denaturant when 

economical has proven effective and manageable by the marketplace. 

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

The Proposed Rule would also limit the maximum concentration of denaturant that can be used 

in denatured fuel ethanol to 2 percent by volume. The Proposed Rule provides little tolerance in 

light of the 1.96 percent minimum level of denaturant required by Alcohol and Tobacco Tax and 

Trade Bureau regulations. A reasonable tolerance should be allowed so as to avoid inadvertent 

compliance issues. 

Our Response:

To limit the potential impact on vehicle emissions of fuel parameters in ethanol 

denaturants other than sulfur, we proposed to limit denaturant concentration in DFE to a 

maximum of 2 volume percent, which translates to 2.5 volume percent considering rounding. 
Tier 3 Summary and Analysis of Comments

5-119

California allows a maximum denaturant content of 5 volume percent consistent with the 

industry consensus ASTM International (ASTM) specification for DFE. 8

Since we did not finalize benzene, olefin, or aromatics specifications for ethanol 

denaturants similar to those in California as part of the Tier 3 FRM, we continue to believe that it 

is appropriate to implement a more stringent limit on maximum denaturant concentration to 

address concerns about the potential impact on vehicle emissions of fuel parameters in ethanol 

denaturants other than sulfur. Denaturants with high benzene content could have a substantial 

impact on the final benzene content of the finished ethanol-gasoline blend. Setting a more 

stringent limit on denaturant concentration will ensure that harmful components such as benzene 

potentially present in ethanol denaturants are adequately diluted in the finished fuel blend. We 

agree with comments that it is appropriate to provide additional flexibility for the allowable 

denaturant levels that may be used. Therefore, we are finalizing a 3.0 volume percent maximum 

on ethanol denaturant concentration. This approach provides sufficient flexibility to DFE 

producers while avoiding the need to impose additional testing burdens on denaturant and DFE 

producers (e.g. for benzene and aromatics). Given the comments that DFE typically contains 

approximately 2 volume percent denaturant, we expect that the 3.0 volume limit that we are 

finalizing will have a minimal impact on the operations of DFE producers and importers.

5.3.3. Compliance Demonstration Including Registration, Testing, Product 

Transfer Document, and Reporting Requirements

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

In the event that EPA finalizes a more stringent 10-ppm refinery average sulfur standard, API 

and AFPM support EPA’s proposal within new §80.1610(a)(1) that producers of denatured fuel 

ethanol (DFE), or other oxygenates, for use by oxygenate blenders be required to meet a 10-ppm 

sulfur cap, as determined in accordance with the test requirements for refiners and importers. 

API and AFPM believe that cumbersome individual batch reporting for all fuels has little value. 

API and AFPM contend that EPA does not need to limit the concentration of denaturant in DFE 

API and AFPM believe that it is unnecessary for EPA to require manufacturers of denaturants to 

register with EPA. We believe that requiring producers of DFE to meet the latest version of 

ASTM International Specification D4806 and TTB denaturant requirements, along with very low 

denaturant concentrations (typically 2 volume percent) would sufficiently limit the risk that 

denaturants might adversely impact vehicle emissions. Therefore, the proposed registration of 

denaturant manufacturers would not provide for any meaningful purpose. 

 

8 ASTM International D4806-13a, “Standard Specification for Denatured Fuel Ethanol for Blending with Gasolines 

for Use as Automotive Spark-Ignition Engine Fuel”.
Chapter 5: Tier 3 Fuel Sulfur Program

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DFE has become a significant component within the gasoline fuel pool and should be subject to 

requirements similar to gasoline refiners. However, API and AFPM believe that individual batch 

reporting for all fuels has little value. We propose that batch records be part of the 

recordkeeping requirements for both refiners and DFE producers but only aggregated reports be 

submitted to EPA. Refiners and DFE producers should be required to keep batch records that 

demonstrate compliance with per-gallons standards and support their annual compliance 

reporting, and should be required to provide records to EPA on demand, similar to how the diesel 

sulfur program is currently structured. However, if EPA insists on batch-level reporting of 

benzene and sulfur for DFE, EPA should require those batch properties be entered into EMTS at 

the same time RINs are generated rather than establishing an entirely new and duplicative batch 

reporting mechanism for DFE producers. 

Commenter: Chevron Products Company

We disagree with the Agency’s assertion that denaturant producer registration and demonstration 

of compliance with the sulfur, aromatics, benzene and olefin content requirements would be 

necessary if the maximum denaturant content is not set at 2 volume percent. In our view, 

adoption of the California DFE requirements in their entirety resolves this issue and obviates the 

need for such burdensome administrative requirements on denaturant producers. 

We concur with the Agency’s proposal that producers of DFE be required to provide annual 

batch reports to the Agency to demonstrate that their product meets the proposed quality 

requirements. DFE manufacturers are required to register their product with the Agency prior to 

introducing DFE into commerce and they routinely test each batch of their product to provide the 

necessary documentation to their customers (i.e., fuel blenders). While we do not necessarily 

agree that the incorporation of DFE batch reporting would ‘facilitate unfettered downstream 

ethanol blending,’ we also do not see it as adding any significant burden to DFE producers. The 

single most important component in facilitating downstream blending is the adoption of uniform 

national specifications for ethanol and, thus, our recommendation of adoption of the California 

requirements. 

Commenter: Flint Hills Resources, LP (FHR)

In addition, individual batch reporting of gasoline or other fuels should not be required. 

Individual Batch Reporting of Gasoline and Other Fuels Should Not Be Required 

FHR believes that reporting of each batch of gasoline under §80.1652 has little value, and EPA 

should not consider individual batch reporting for DFE producers. FHR agrees that batch records 

should continue to be part of the recordkeeping requirements within §80.1653, but only 

aggregated reports be submitted to EPA. Similar to how the diesel sulfur program is currently 

structured, fuel producers should be required to keep batch records that demonstrate compliance 

with standards and support annual reporting. Individual batch records would be made readily 

available to EPA upon request or during inspections.

Commenter: Growth Energy
Tier 3 Summary and Analysis of Comments

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Denaturant manufacturers should not be required to register with EPA.

EPA requests comment “on whether to require manufacturers of denaturants for use in DFE to 

register with EPA, and demonstrate compliance with the maximum sulfur, benzene, olefins, and 

aromatics specifications enforced in the State of California based on the anticipated dilution with 

ethanol.” 

EPA should not require denaturant manufacturers to register with the EPA. Doing so would limit 

supply and unfairly increase production costs on the ethanol industry. Gasoline component 

manufacturers are not required to register, e.g., manufacturers of pyrolysis gasoline, natural 

gasoline, and chemical byproducts. We believe a registration requirement would limit the 

number of denaturant suppliers willing to supply the ethanol industry, versus the gasoline or 

crude blending markets where they would not need to register. It is inappropriate that a natural 

gasoline producer would need to register in order to supply product for DFE, but not need to 

supply the same product to a gasoline blender. The requirements should be similar to keep the 

market competitive and provide a level playing field to both gasoline and ethanol. 

EPA also proposes that DFE manufacturers would be subject to batch testing (including batch 

volume, sulfur content, and denaturant concentration as applicable). While the final ethanol 

blends (e.g., E30, E85, or some other blend ratio from E16 to E85) would not necessarily be 

subject to batching testing, EPA here proposes that the DFE would be tested. 

Commenter: Marathon Petroleum Company LP (MPC)

In the event that EPA finalizes a more stringent 10-ppm refinery average sulfur standard, MPC 

supports EPA’s proposal within new §80.1610(a)(1) that producers of denatured fuel ethanol 

(DFE), or other oxygenates, for use by oxygenate blenders be required to meet a 10-ppm sulfur 

cap, as determined in accordance with the test requirements for refiners and importers.

MPC believes that it is unnecessary for EPA to require manufacturers of denaturants to register 

with EPA. We believe that requiring producers of DFE to meet the latest version of ASTM 

International Specification D4806 and TTB denaturant requirements, along with very low 

denaturant concentrations (typically 2 volume percent) would sufficiently limit the risk that 

denaturants might adversely impact vehicle emissions. Therefore, the proposed registration of 

denaturant manufacturers would not provide for any meaningful purpose. 

DFE has become a significant component within the gasoline fuel pool and should be subject to 

requirements similar to gasoline refiners. However, MPC believes that individual batch reporting 

for all fuels has little value. We propose that batch records be part of the recordkeeping 

requirements for both refiners and DFE producers but only aggregated reports be submitted to 

EPA. Refiners and DFE producers should be required to keep batch records that demonstrate 

compliance with per-gallons standards and support their annual compliance reporting, and should 

be required to provide records to EPA on demand, similar to how the diesel sulfur program is 

currently structured. However, if EPA insists on batch-level reporting of benzene and sulfur for 

DFE, EPA should require those batch properties be entered into EMTS at the same time RINs 
Chapter 5: Tier 3 Fuel Sulfur Program

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are generated rather than establishing an entirely new and duplicative batch reporting mechanism 

for DFE producers. 

Commenter: POET, LLC

EPA should not require denaturant manufacturers to register with the EPA. Doing so would limit 

supply and unfairly increase production costs on the ethanol industry. Gasoline component 

manufacturers are not required to register, e.g., manufacturers of pyrolysis gasoline, natural 

gasoline, and chemical byproducts. POET believes a registration requirement would limit the 

number of denaturant suppliers willing to supply the ethanol industry, versus the gasoline or 

crude blending markets where they would not need to register. It is inappropriate that a natural 

gasoline producer would need to register in order to supply product for DFE, but not need to 

register to supply the same product to a gasoline blender. The requirements should be similar to 

keep the market competitive and provide a level playing field to both gasoline and ethanol.

Commenter: Renewable Fuels Association (RFA)

Because denaturants are the sole source of sulfur in denatured fuel ethanol (DFE), the EPA 

should not require sulfur content batch reporting by DFE producers. Current practices for 

monitoring the sulfur content of denaturant and DFE are adequate. 

However, if EPA finalizes the currently proposed regulatory language pertaining to batch 

reporting, it would create a substantial and unnecessary cost burden for DFE producers. 

The EPA may not know that ethanol production facilities do not have the laboratory capability to 

analyze for sulfur content. This proposed regulation as written would be an expensive endeavor 

for ethanol producers. 

Since the California sulfur specifications were adopted, ethanol facilities have worked closely 

with their denaturant suppliers (mostly natural gasoline marketers) to supply a Californiacompliant denaturant that results in a finished DFE with less than 10 ppm sulfur. Ethanol 

producers require denaturant suppliers to provide a low sulfur product that also meets the other 

attributes of the California regulations pertaining to benzene, olefins and aromatics content. A 

certificate of analysis is received with each denaturant delivery. Ethanol production facilities 

reference the sulfur content on the certificate of analysis, which is typically a quarterly reported 

number recorded by third party commercial laboratories using the latest version of ASTM Test 

Method D5453.

What EPA is proposing via §80.1610 is that producers of DFE be required to meet the proposed 

fuel quality requirements for their product and sample and test each batch produced and provide 

batch reports to EPA. This is similar to the requirements for gasoline refiners. This would require 

all ethanol production facilities to purchase lab equipment to analyze for sulfur Using ASTM 

D5453; the most widely used and accepted method for DFE. Just the initial equipment 

investment for this test method is expected to be $60,000 at a minimum for each location, not to 

mention training and personnel time to perform this work. If finalized, this proposed regulation 

would require the ethanol industry to initially invest over $12 million dollars in lab equipment to 
Tier 3 Summary and Analysis of Comments

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analyze daily for sulfur content of less than 10 ppm that the industry has been in voluntary 

compliance since 2002. 

Results from the ASTM Interlaboratory Crosscheck Program (ILCP) for DFE further underscore 

the superfluous nature of the proposed batch reporting. RFA participates in many areas within 

ASTM including the test methods committee and ILCP for DFE. The ILCP program for DFE has 

fifty laboratories that participate in the blind analytical testing of DFE using the ASTM D5453 

test method for sulfur content. The collection of data has been statistically analyzed and shows 

DFE typically has sulfur content in the range of 1 – 5 ppm. In many cases, sulfur levels are so 

low that precision problems have arisen in attempting to analyze sulfur content. 

For these reasons, RFA is requesting some relief from the batch reporting requirements proposed 

in § 80.1610. We believe EPA should allow continuation of current practices for denaturant 

blending/sulfur limit compliance instead of following the proposed §80.1630 sampling and 

testing requirements for refiners and importers. The sulfur content of the DFE can be monitored 

mathematically, based on the incoming certificate of analysis supplied by the denaturant 

manufacturer and confirmed via a third party commercial laboratory by sampling and testing 

DFE on a defined periodic basis utilizing standard test methods. Additional recordkeeping 

requirements for DFE producers (beyond what is specified in the proposal) could be part of this 

procedure. Producers would need to maintain the certificate of analysis showing denaturant 

sulfur content and the calculations used to determine DFE sulfur content as evidence that DFE 

meets the 10 ppm sulfur requirements. They would also have to perform standard quality 

assurance activities with the denaturant supplier by sampling incoming shipments of denaturant 

for sulfur content against the specified certificate of analysis on a frequent basis. 

This would be similar to the way butane is treated in the proposed §80.82 pertaining to butane 

blending. The current regulations reduce the burden of compliance with EPA gasoline quality 

requirements for parties that blend butane into conventional gasoline, reformulated gasoline 

(RFG), or reformulated blendstock for oxygenate blending (RBOB) downstream of a refinery. 

Parties that conduct such butane blending are considered refiners; however, they are not subject 

to sampling and testing requirements that would otherwise apply to a refiner provided they use 

butane of known quality and meet certain other requirements. Proposed language for butane 

blending states that any refinery that blends butane for which the refinery has documents from 

the butane supplier which demonstrate that the butane is commercial grade may demonstrate 

compliance with the standards based on the properties specified by the butane supplier. We are 

simply seeking the same treatment for blending of denaturant with ethanol.

EPA should adopt the current California regulatory practice of certifying the sulfur content of 

denatured fuel ethanol as this certification system has proven extremely effective. Recently, 

California has taken steps to preserve the sulfur content certification which confirms the ethanol 

industry’s standard practice as accurate. 

The above suggested changes to the current proposed language regarding validation of sulfur 

content in DFE, which mimic the California regulations, will not compromise the intentions of 

the gasoline sulfur proposed limit of 10 ppm maximum.
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§80.1651 Product transfer document requirements. The product transfer document from Subpart 

M § 80.1453 product transfer document requirements for the ethanol producers under the 

Renewable Fuels Standard contains the same information and should be allowed to suffice for 

§80.1651 with the additional statement as required by §80.1610(c)(1) “Meets EPA standards for 

denatured fuel ethanol for use in gasoline.” Under the RFS program’s EMTS platform, the 

ethanol industry already has a batch numbering system and PTD requirements. Requiring 

another unique batch number for the sulfur program by §80.1610(d) is redundant and not 

necessary for tracking batches of product. 

§80.1652 Reporting requirements. Ethanol producers are required to annually report production 

volumes under fuels and fuel additives (FFARs) (40 CFR 79 Subparts A, B, C, D, and F). We 

suggest simply adding a check box to form 3520-13A Fuel Additive Manufacturer Report to 

include the §80.1652(c)(3) attestation. 

In lieu of requiring sulfur content batch reporting for DFE producers, we recommend the 

following changes to 80.1653 to ensure that DFE producers can demonstrate, upon request, that 

the sulfur content of the denaturant used for DFE blending resulted in a final DFE blend with 

less than 10 ppm sulfur: 

Denaturant manufacturers should be required to demonstrate compliance with the sulfur 

specifications enforced in the State of California. We feel compelled to point out again that the 

primary source of sulfur in DFE is the hydrocarbon denaturant itself. Very little sulfur is 

contained in the feedstocks and processing aids used for ethanol production. Thus, the primary 

concern for ethanol producers regarding proposed sulfur limits on ethanol is continued access to 

low sulfur hydrocarbon denaturants. As such, EPA could consider a sulfur maximum for 

denaturant, similar to California’s regulations. 

Overall, RFA is not opposed to the DFE sulfur content standards, provided that sufficient 

supplies of low sulfur denaturant continue to be available. 

Our Response:

To demonstrate compliance with the Tier 3 program 10 ppm sulfur cap for gasoline 

oxygenates, we proposed that producers and importers of oxygenates would be required to test 

the sulfur content of each batch of oxygenate they produce. We also requested comment on 

whether to require producers of denaturants for use in denatured fuel ethanol DFE to register 

with EPA and to demonstrate compliance with a maximum sulfur specification based on the 

anticipated dilution with ethanol. With DFE now comprising essentially 10 percent of the 

gasoline supply, it is important that EPA have effective means of enforcing gasoline quality 

standards, particularly given that the majority of DFE is blended into gasoline at a large number 

of diverse locations downstream of the refinery gate. We appreciate the desire of the industry to 

avoid regulation. However, important emissions and air quality improvements resulting from 

our fuel standards would be at risk without EPA’s ability to readily enforce gasoline quality 

standards. 
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DFE producers currently use certificates of sulfur analysis from denaturant producers and 

volumetric DFE blending records to assure themselves that when a sample of DFE is tested by 

the State of California that it will be found to be compliant with a 10 ppm sulfur cap.9 Under this 

approach, DFE producers would maintain records regarding the denaturant sulfur content and the 

calculations used to determine the sulfur content of the finished DFE. Because the sulfur content 

of neat (un-denatured) ethanol manufactured using industry standard quality control practices 

should be negligible, the sulfur content of DFE is effectively determined by the sulfur content of 

denaturant used.10 

EPA agrees that is appropriate to finalize requirements for the demonstration of 

compliance with the 10 ppm sulfur cap for DFE that are based on current industry practices 

rather than requiring sulfur testing on each batch of DFE.11 We agree that that potential 

contribution to the sulfur content of DFE other than from the addition of denaturants can be 

adequately addressed by the retention of production quality control records by the ethanol 

manufacturer. We also agree that the denaturant typically contributes the majority of the sulfur 

to the finished DFE. Therefore, the Tier 3 FRM finalized streamlined provisions that DFE 

producers and importers may use in demonstrating compliance with the 10 ppm sulfur cap for 

DFE as an alternative to testing each batch of DFE for its sulfur content. These streamlined 

provisions are based on the use of denaturant batch sulfur testing conducted by denaturant 

producers who have registered with EPA. Denaturants from unregistered denaturant producers 

may be used by DFE producers provided that they test each batch of DFE to demonstrate 

compliance with the 10 ppm sulfur cap for DFE.12

DFE manufacturers that use denaturants that have been designated on the denaturant 

product transfer document (PTD) as a certified ethanol denaturant will be able use PTDs for the 

denaturants used and volumetric blending records which show that the denaturant was added at 

3.0 volume percent or less in demonstrating compliance with the 10 ppm sulfur cap for DFE in 

lieu of per-batch sulfur testing of DFE. The sulfur content of “neat” (i.e. un-denatured) ethanol 

may be assumed to be negligible for the purposes of demonstration of compliance using 

volumetric blending records provide that the DFE manufacturer maintains quality control records 

that demonstrate this assumption is justified. The Tier 3 FRM rule also requires that DFE 

manufacturers conduct quality assurance to demonstrate affirmative defenses to presumptive 

liability.

13

 Producers and importers of DFE must initiate a PTD to accompany each batch of 

DFE which states that it meets federal standards. 

 

9 The State of California does not rely on industry testing and recordkeeping to help establish compliance with their 

sulfur requirements for DFE, instead choosing to focus on direct testing that they conduct. EPA relies on the review 

of industry records including those associated with tesing conducted by industry as well as direct testing conducted 

by EPA for compliance assurance.

10 Ethanol manufacturers conduct periodic sulfate testing on neat ethanol to ensure that sulfur contamination from 

the manufacturing process is negligible. 

11 Per-batch sulfur testing for other potential oxygenates will be required to demonstrate compliance with the 10 

ppm sulfur cap. EPA may consider amending the requirements for other potential oxygenates in a later rulemaking 

based on additional information that we might receive.

12 The limitation on the types of denaturants that may be used and the maximum concentration at which a denaturant 

may be used (discussed in section V.G.2 and 3 of the Tier 3 FRM) applies regardless of whether a denaturant from a 

registered or non-registered denaturant manufacture are used.

13 Such quality assurance practices include periodic calibration of the denaturant blending equipment to ensure that 

denaturants are not added in excess of 5 volume percent.
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Denaturant manufacturers are accustomed to providing certificates of sulfur analysis to 

DFE manufacturers. Therefore, we believe that the requirements finalized today for denaturant 

manufacturers to conduct per-batch sulfur testing, initiate a product transfer document stating 

that denaturant is suitable for use in manufacturing DFE that meets federal requirements, retain 

records, and register with EPA will not represent a substantial new burden. To facilitate 

compliance with the requirement that DFE manufacturers who use the mathematical method to 

demonstrate compliance with DFE sulfur requirements must only use denaturants from 

registered denaturant manufacturers. Registering with EPA will be a one-time act, as will be the 

necessary modifications to denaturant product transfer documents. Thus, the requirement to 

register with EPA should not be a serious impediment for a manufacturer to enter the denaturant 

supply market. We believe that it is necessary to require denaturant manufacturers to register 

with EPA in order to facilitate compliance oversight. EPA needs to be able identify all 

manufacturers of denaturants in order to periodically audit their records, and to recognize 

potential denaturants in the system that are incorrectly designated as appropriate for use in 

manufacturing DFE that meets federal sulfur requirements. Denaturant manufacturers that 

supply their product to refiners for use in the manufacture of gasoline are not required to register 

with EPA because, unlike the DFE manufacturers, refiners are responsible for testing the final 

gasoline they produce.

As is current practice today, we anticipate that ethanol manufacturers will negotiate the 

specific sulfur level they require from denaturant manufacturers to facilitate compliance with the 

10 ppm sulfur cap for DFE taking into consideration what level of compliance margin a given 

manufacturer feels is necessary. We believe that it is appropriate to allow this practice to 

continue. We understand that ethanol manufacturers currently require denaturant manufacturers 

to provide a product with a sulfur content of 120 ppm or less in order to ensure that DFE that 

contains 5 volume percent denaturant can comply with California’s 10 ppm sulfur cap for DFE. 

Thus, we expect that denaturant manufacturers will not need to change the sulfur content of the 

denaturant they manufacture in order to comply with the Tier 3 requirements. Manufacturers of

denaturants used by DFE producers that employ the volumetric blending record method in 

demonstrating compliance with the sulfur requirements for DFE must retain per batch sulfur test 

data on the denaturants they produce to demonstrate that the sulfur content of the denaturant will 

not cause the sulfur content of DFE to exceed 10 ppm when added to neat ethanol at 3.0 volume 

percent. Any sample of denaturant which is designated as appropriate for use in manufacturing 

DFE that meets federal requirements, that is found by EPA to have sulfur content above 330 ppm 

will be deemed to be noncompliant, and the denaturant manufacturer may be liable for the 

associated penalties. A denaturant with a sulfur content of 330 ppm when used at 3.0 volume 

percent would result in a sulfur content of the finished DFE of slightly less than 10 ppm.

We continue to believe that annual reports from oxygenate producers (as well as gasoline 

refiners and importers) are important enforcement and compliance assurance tool. Therefore, we 

are finalizing the requirement that producers and importers of DFE and other oxygenates must 

submit annual reports to EPA that include the total volume of DFE/oxygenate produced and an 

attestation that all batches met the proposed fuel quality requirements. The flexibilities provided 

in the Tier 3 rule will allow DFE producers and importers to avoid testing DFE production 

batches, thereby avoiding substantial capital costs to comply with the Tier 3 requirements. We 
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do not believe that it appropriate to provide additional regulatory relief to DFE producers and 

importers from registration, reporting, and recordkeeping requirements. As noted above, these 

requirements are essential to ensure the quality of a substantial fraction of the total volume of 

motor vehicle fuel.

In response to comments, EPA will work with stakeholders to evaluate the potential for use of 

EMTS and other existing EPA mechanisms to meet some of the reporting requirements for DFE 

producers and importers.

5.3.4. Other

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

 Petrochemical Manufacturers (AFPM)

Ethanol has become a significant component within the gasoline fuel pool and should be subject 

to requirements similar to gasoline refiners. 

Commenter: Growth Energy

We promote expanding the use of ethanol in gasoline, decreasing our dependence on foreign oil, 

improving our environment and creating American jobs. Ethanol is a home-grown, renewable 

fuel that provides significant benefits to our nation’s air quality. We vigorously support the 

Renewable Fuel Standard (RFS) and the continued use of ethanol in our nation’s fuel supply as it 

significantly reduces carbon monoxide, particulate matter and greenhouse gas emissions. As 

such, we are pleased to have this opportunity to comment on the Agency’s proposed “Tier 3” 

Emission and Fuel Standards as there are several key issues that, when addressed, will continue 

to promote the expanded use of biofuels in our nation’s transportation fuel system. 

We also have several concerns about some of the specific standards for Denatured Fuel Ethanol 

(DFE). 

EPA must not burden the ethanol industry with additional, unnecessary production restrictions: 

EPA must not burden the ethanol industry with additional, unnecessary production restrictions. 

These restrictions include both the specifications for DFE (denatured fuel ethanol) as well as the 

process of blending gasoline with DFE to create ethanol-blended fuels. 

Commenter: Chevron Products Company

We concur with the Agency’s opinion that the proposed fuel specifications for DFE also apply to 

other oxygenates used in gasoline. The January 1, 2017 effective date for oxygenate 

producers/importers to meet the new quality requirements seems reasonable in that it appears to 

provide sufficient lead time for any manufacturing process modifications that oxygenate 

producers may need to make to comply. However, should EPA decide to extend the overall 
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program start date to a date that occurs after January 1, 2017, the effective dates for new DFE 

requirements should be extended to be consistent with the overall Tier 3 program. 

Commenter: Marathon Petroleum Company LP (MPC)

DFE has become a significant component within the gasoline fuel pool and should be subject to 

requirements similar to gasoline refiners. 

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

It appears that an importer of ethanol that is denatured upon entry or already denatured would 

qualify as a ‘producer’ of denatured ethanol. Sutherland believes that EPA should clarify this 

point. 

Our Response:

We agree with the comment that additional requirements for denatured fuel ethanol 

(DFE) are necessary to ensure DFE quality. With DFE now comprising essentially 10 percent of 

the gasoline supply, it is important that EPA have effective means of enforcing gasoline quality 

standards, particularly given that the majority of DFE is blended into gasoline at a large number 

of diverse locations downstream of the refinery gate. We appreciate the desire of the ethanol 

industry to avoid regulation. However, important emissions and air quality improvements 

resulting from our fuel standards would be at risk without EPA’s ability to readily enforce 

gasoline quality standards. As discussed in chapter 5.3., we have included flexibilities in the 

requirements for denatured fuel ethanol that will minimize the burden on DFE producers.

We have amended the regulatory text to further clarify that denatured fuel ethanol 

importers as well as producers are subject to DFE quality requirements.

We agree with the comment that the specifications for DFE should also apply to other 

gasoline oxygenates. This is reflected in the oxygenate requirement that we are finalizing.

We agree with the comment that the January 1, 2017 effective date for oxygenate 

producers/importers to meet the new quality requirements that we are finalizing in the Tier 3 

final rule provides sufficient time for the industry to prepare to comply 

5.4. Standards for Fuel Used in Flexible Fueled Vehicles (E51-83 and Mid-Level (E16-

50) Blends)

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of 

Global Automakers (Global)
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Recommendations for E51-83 and E16-50 Market Fuel Specifications – E51-E83: As EPA notes, 

(86) the standards for E51-83, “Ethanol Fuel Blends for Flexible-Fuel Automotive Spark Ignition 

Engines” have been changing rapidly in recent years. Indeed, a revised specification, ASTM 

D5798-13, issued in May, 2013. The most significant driver for the recent revisions to the E51-

83 specification was the inability of terminals to blend E85 that met the requirements of the E85 

specification using current gasoline and BOBs (blend stock for oxygenate blending). The low 

vapor pressures of modern gasoline made it difficult to meet the vapor pressure minima 

prescribed by the specification, even at the maximum rate of gasoline addition. After running a 

test program to determine that the fuel vapor pressure requirements could not be changed, the 

ASTM task group decreased the minimum allowable ethanol percentage to 51% as the best way 

to enable E51-83 blends with compliant RVPs. The higher allowed level of gasoline is required 

not just to meet cold weather vapor pressure requirements but also to meet summer requirements 

when using the low vapor pressure RBOBs (Reformulated Blend-stocks for Oxygenate 

Blending) used in many areas of the U.S. 

We agree with EPA’s proposal to subject E51-83 to the same sulfur, benzene and RVP 

requirements as gasoline. It is important that producers of E51-83, where they are merely 

oxygenate blenders, be exempt from the regulatory burden that falls on those EPA classifies as 

“refiners.” The goal of this regulation is to ensure that blenders produce E51-83 blends that are 

compliant to the gasoline sulfur, RVP and benzene standards, while avoiding all the sampling, 

testing, and reporting obligations of refiners. To this end, requiring blenders to maintain records 

including the certificates of analysis, product transfer documents, and the ratios used to blend the 

fuel, would be sufficient to document that the resultant blends were compliant with EPA 

standards. 

E16-50 

We recommend that EPA treat E16-50 as an alternative fuel for use in FFVs or other vehicles 

specifically certified for use with these fuels (87). These fuels should be subject to the same 

sulfur, benzene and RVP requirements as gasoline. It is important that producers of E16-50, 

when they are merely oxygenate blenders, also be exempt from the regulatory burden that falls 

on those EPA classifies as “refiners” as noted in the preceding section. 

86 - 78 Fed. Reg. 29908 at 29937 (May 21, 2013).

87 - 78 Fed. Reg. 29908 at 29937-29938 (May 21, 2013).

Commenter: American Coalition for Ethanol (ACE)

Standards for E51-E83 (new ASTM spec): In keeping with EPA intent to provide test fuels that 

approximate those actually used by vehicle operators, and in the interest of providing ethanol 

producers with similar flexibility given to refiners for decades, ACE supports specifications 

consistent with ASTM D5798-13 and would recommend allowing the use of blendstocks such as 

natural gasoline and butane in certification fuels. 

Standards for Mid-level Ethanol Blends (E16-E50): As mentioned earlier, unless and until a 

definitive new ethanol blend is established by auto manufacturers, ACE believes other ethanol 
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certification fuels should be created using E10 or E15 blendstocks along with Denatured Fuel 

Ethanol or ethanol flex fuel, since that is the way such fuels would likely be created in the 

marketplace 

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

API and AFPM agree that E16-50 ethanol blends for use in FFV should meet the same sulfur, 

RVP, and benzene standards, and minimum deposit control requirements otherwise applicable to 

gasoline. API and AFPM do not agree that EPA should treat E16-50 as gasoline under current 

regulations. In API’s and AFPM’s view, this action would require formal rulemaking with a 

waiver from the substantially similar requirements. 

While API and AFPM may support EPA’s effort to develop regulations for E51-E83, the process 

EPA used to inform the regulated community runs afoul of the federal Administrative 

Procedures Act (APA) and the federal Clean Air Act (CAA). These additional regulations 

include prescribing new requirements for E51-E83 for key fuel properties such as sulfur, RVP, 

and benzene, although the benzene limits proposed would preclude the use of some denaturants, 

and EPA should set E51-83 benzene standards similar to gasoline standards. 

Standards for E16-50: API and AFPM agree that E16-50 ethanol blends for use in FFV should 

meet the same sulfur, RVP, and benzene standards otherwise applicable to gasoline. API and 

AFPM do not agree that EPA should treat E16-50 as gasoline under current regulations. In API’s 

and AFPM’s view, this action would require formal rulemaking with a waiver from the 

substantially similar requirements in CAA section 211(f).

EPA is proposing that gasoline deposit control requirements be removed from the E16-50 and 

E51-83 fuels. API and AFPM believe that it is in the best interest of the consumer to maintain a 

deposit control requirement for all spark-ignition fuels at a minimum level to protect the engines 

of consumers. 

Standards for E51-83: EPA’s preamble to the proposed Tier 3 regulations references a separate 

memorandum (38) that includes additional proposed regulations for which EPA seeks comments. 

These additional regulations include prescribing new requirements for E51- E83 for key fuel 

properties such as sulfur, RVP, and benzene. While API and AFPM may support EPA’s effort to 

develop regulations for E51-E83, the process EPA used to inform the regulated community runs 

afoul of the federal Administrative Procedures Act (APA) and the federal Clean Air Act (CAA). 

The APA is clear that EPA’s forum for informing the public of substantive rules, amendments, 

and revisions is through the Federal Register. Further, the APA states “except to the extent that a 

person has actual and timely notice of the terms thereof, a person may not in any manner be 

required to resort to, or be adversely affected by, a matter required to be published in the Federal 

Register and not so published.” 

Section 307(d)(3) of the CAA echoes the requirement for proposed rules to be published in the 

Federal Register. Among other things, the notice must “specify the period available for public 
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comment.” In addition, at the time of publication, there must be a publicly available docket that 

includes: (1) the factual data on which the proposal is based; (2) an explanation of how EPA 

collected and analyzed the data; and (3) an explanation of the major legal interpretations and 

policy considerations underlying the proposal. 

In the instant matter, EPA describes and seeks comment on very significant potential changes to 

the regulations. EPA is required, by law, to publish such a proposal in the Federal Register. 

Posting on EPA website or including within the rulemaking docket is not an option – publication 

in the Federal Register means publication in the Federal Register. EPA must include all proposed 

changes in the proposed rule. References to documents external to the proposed rule do not give 

the regulated community and public the opportunity to which it is entitled to generate informed 

and timely comments regarding the proposed rule. 

Notwithstanding the APA requirement to publish proposed rules within the Federal Register, 

API and AFPM would like to provide the following comments to the Jeff Herzog Memorandum 

dated April 8, 2013 that is posted within the docket (ID: EPA–HQ–OAR–2011–0135-0529): 

API and AFPM agree that E51-83 for use in Flexible Fueled Vehicles (FFV) should be required 

to meet the same sulfur, maximum Reid Vapor Pressure (RVP), and benzene standards otherwise 

applicable to gasoline, as well as the Clean Air Act Section 211(f)(1) substantially similar 

provision. EPA should also allow for the use of butane or other natural gas liquids (e.g. pentane, 

natural gasoline, etc.) to manufacture E51-83 with sufficient volatility to meet the ASTM D5798 

specifications. API and AFPM do not support limits on specific components, but do support 

adoption of reasonable standards to facilitate blending. 

However, API and AFPM have identified a serious concern with the suggested 0.20 volume 

percent benzene cap for E51-83. Requiring E51-83 to meet a 0.20 volume percent benzene cap 

would effectively preclude the blending of gasoline blendstock and natural gasoline to 

manufacture E51-83. As EPA states, refiners and importers of gasoline are subject to a 0.62 

volume percent annual average and 1.3 volume percent maximum average benzene standard. 

Furthermore, natural gasoline typically contains in excess of 1 volume percent benzene. As an 

example, E51-83 composed of 49 percent gasoline blendstock with 1.3 volume percent benzene 

and 0.01 percent natural gasoline denaturant with 1 volume percent benzene could have a 

resulting benzene content exceeding 0.65 volume percent. In another example, E51-83 composed 

of 17 percent gasoline blendstock with 1.3 volume percent benzene and 1.7 percent natural 

gasoline denaturant with 1 volume percent benzene could have a resulting benzene content 

exceeding 0.24 volume percent. Therefore, the setting of a 0.20 volume percent benzene cap 

would interfere with the expansion of E51-83 into the marketplace by preventing blends at the 

both the upper and lower range of the allowable ethanol content. To resolve this issue, API and 

AFPM recommend that E51-83 be required to meet the same benzene standards applicable to 

gasoline. 

API and AFPM support EPA’s suggested requirement that compliance with the Section 211(f)(1) 

substantially similar provision would be effectively achieved by ensuring that E51-83 be 

composed solely of carbon, hydrogen, nitrogen, oxygen, and sulfur. 
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API and AFPM agree that manufacturers of E51-83 for use in FFV should also be subject to the 

full responsibilities of a refiner (e.g. registration; batch sampling and testing; and reporting

obligations), which is outlined as Option 1 within the Herzog Memorandum. However, if EPA 

wishes, as a second option, to allow oxygenate blenders to be exempt from the sampling, testing 

and reporting obligations of refiners, oxygenate blenders should be required to only use gasoline 

blendstocks, denatured fuel ethanol, natural gas liquids (NGL) and butane that meet certain 

specifications. API and AFPM agree with this two-option approach as a means to not restrict 

refiners or oxygenate blenders from choosing maximum blending flexibility by meeting the more 

stringent requirements, as outlined within Option 1. API and AFPM also agree that any resulting 

E51-83 should also be required to meet the downstream sulfur, RVP and benzene per-gallon cap 

standard.

API and AFPM agree that it may be possible to develop a calculative approach for E51-83 

blenders to determine RVP and avoid sampling and testing. We agree that testing may be 

required for some period of time when a blender receives a new batch of gasoline blendstock. 

We also agree that RVP of different batches of DFE would not vary significantly due to TTB 

requirements related to denaturants and denaturant percentages, along with RFS2 requirements 

related to denaturant concentrations for RIN generation.

API and AFPM agree that butane used for E51-83 blending should meet the same standards as 

specified for butane blended into gasoline at a terminal. However, the limits on other 

components in E51-83 should be restricted to their total contribution toward regulated properties 

on the final fuel, not the same limits imposed on the components. Sources for NGLs should not 

be limited, provided the NGL conforms to the requirements. 

Commenter: BP Products North America Inc.

Standards for E51–83- Meeting the ultimate goals of the Renewable Fuel Standard is highly 

dependent upon the expansion of E51–83 into the marketplace. BP, therefore, supports EPA’s 

proposal to allow the use of butane and natural gas liquids to manufacture E51-83. BP also 

agrees that the final blend should meet the same sulfur, RVP, and benzene standards otherwise 

applicable to gasoline. BP does not support imposing tighter standards on E51-83, such as EPA’s 

proposed 0.2 wt. % benzene.

EPA has proposed alternate conformance demonstrations with RVP requirements for E51- 83. 

Under option 2, the blender could use a blending model and measure the RVPs of the blending 

components. Alternatively the blender could use reduced frequency testing to verify vapor 

pressure conformance. BP is supportive of these options which will provide greater flexibility for 

E51-83 blending. 

Standards for Butane and Natural Gas Liquids (NGLs)- BP supports the limits on butane 

composition that match those used now for butane blending of gasoline at the terminal. BP’s 

experience has shown that only relatively low levels (one to few percent) of butane are needed to 

bring ethanol blends into vapor pressure conformance with ASTM D 5798 specification. In 

general, one volume percent butane raises vapor pressure of flex fuel about 1 psi. Hence an upper 

limit on butane is self-determined by the vapor pressure limits of D 5798 specification. Limits on 
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other components in E51-83, including NGLs, should be restricted to their total contribution 

toward regulated properties on the final E51-83 blend. Imposing the same limits on individual 

blending components, would severely limit the blending of such components. BP also 

recommends that EPA not restrict the use of NGLs to natural gas processing plants. If NGLs are 

used in the blending of E51-83 and the final blend conforms to the necessary requirements, 

restricting the source of NGLs is unnecessary. 

BP further recommends that EPA not impose upper limits on the concentration for butane and 

NGL’s in E51-83 blending, however, does support adoption of reasonable standards to facilitate 

such blending. 

For additional flexibility, BP also encourages EPA to allow blending of pentanes as a means of 

increasing flex fuel vapor pressure to allow conformance with ASTM D 5798 specification for 

flex fuel blends. 

Establish Gasoline Deposit Control Requirements for E51-83– BP recommends that gasoline 

deposit control requirements be imposed upon E51-83 and mid-level ethanol blends. It is in 

consumers’ best interest to establish a deposit control requirement for all spark-ignition fuels, in 

order to protect their engines. 

Pump Dispenser Label for E51-83 -BP supports the use of the following pump dispenser label 

for E51-83 and a consumer education program on flexible fuel vehicles, E51-83, E16-50 and the 

terms ‘flex fuel’ and E85. 

Commenter: California Air Resources Board (CARB)

CARB staff also supports the proposed requirements for midlevel ethanol blends, as well as 

promoting the power plant design advantages of an E30 blend. 

Commenter: Chevron Products Company

Standards for Flexible-Fuel Vehicle Fuel and Mid-Level Ethanol Blends: Chevron actively 

participated in the development of the API/AFPM comments on these topics. We refer you to 

those comments as our detailed feedback on this section. 

Commenter: Energy Future Coalition and Urban Air Initiative

EPA Should Enable a Market for Optimized, Dedicated, and Flex- Fuel Vehicle Production 

through Recognition of Ethanol’s Life-Cycle GHG Benefits. As was the case in the transition 

from leaded to unleaded gasoline, a mid-level ethanol blend cannot be made available 

nationwide, and market forces will not prompt any greater availability, until vehicles designed to 

run on this fuel are in widespread use. Meanwhile, legacy vehicles designed for conventional 

gasoline (E0) will not perform adequately on a mid-level ethanol blend, while new optimized or 

dedicated vehicles will not perform adequately on much lower-octane, conventional E10 fuel. 

EPA, however, can break through this impasse by encouraging automobile manufacturers to 

equip new vehicles (beginning in model year 2017) with FFV capabilities that enable the 
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vehicles to run on both conventional fuel and the new mid-level ethanol blend (as well as higher 

ethanol blends such as E85), thereby opening the door to a new generation of engines optimized 

for the new fuel as it becomes available (and eventually standard). (141) 

FFV technology is both widely available and relatively inexpensive, and it can build a bridge to a 

cleaner fuel standard by solving the transitional problem of engine and fuel compatibility that 

must precede an aromatics phase-down. Manufacturers can equip any new vehicle with FFV 

technology that senses the alcohol content of the fuel being used and adjusts the engine’s timing 

accordingly. With the right incentives, this technology could be installed in every new vehicle in 

the country. This would avoid potential legacy fleet issues when automobile manufacturers begin 

to optimize or dedicate all vehicles to run on cleaner fuel and when EPA begins to require 

aromatics reductions in standard market fuel. Legacy vehicles would, at that point, be mostly 

FFVs capable of running on the new fuel. 

In order to begin to phase in a cleaner, higher-ethanol fuel that significantly reduces air toxics 

and other dangerous pollutants, while at the same time helping manufacturers design more 

efficient engines to reduce GHG pollution, EPA should allow all vehicles capable of running on 

a mid-level ethanol blend (dedicated, optimized, or FFV) to be certified for purposes of GHG 

emissions and fuel economy on the new high-octane, mid-level ethanol blend. 

EPA Should Grant the New Mid-Level Ethanol Blend the Same One-Pound RVP Waiver 

Congress Granted to E10. As gasoline evaporates, VOCs enter the atmosphere, producing PM 

and contributing to pollution. (151) The Reid vapor pressure (RVP) of gasoline refers to the 

tendency of gasoline to evaporate and is measured in pounds per square inch (psi). In order to 

prevent VOCs from forming ozone and PM pollution in the presence of sunlight 

(“photochemical smog”), Congress required gasoline to be limited to a maximum RVP of 9.0 psi 

during the summer ozone season as part of the 1990 Clean Air Act Amendments. (152) In 

addition, Congress authorized EPA to set more stringent standards for certain non-attainment 

areas or former non-attainment areas. (153) EPA limits “high-volatility non-attainment” areas to 

a maximum RVP of 7.8 psi during the summer ozone season. (154) During the summer ozone 

season, about 75% of gasoline is 9.0 psi. 

In its neat form (when not blended with gasoline), ethanol’s RVP is much lower than that of 

conventional gasoline (pure ethanol’s RVP is approximately 2.0 psi). However, due to an 

azeotropic effect when blended in small percentages with gasoline, ethanol can increase the 

overall blend’s volatility. (155) As a result, ethanol splash-blended with gasoline at 10% has a 

tendency to raise vapor pressure by approximately one pound. (156) Because of this effect, 

Congress also stipulated in the Clean Air Act Amendments that gasoline containing 10% ethanol 

would be permitted to exceed the applicable maximum RVP by one psi (the “one-pound 

waiver”). (157) In its regulations implementing this section of the statute, EPA specified that the 

waiver only applies to blends containing “at least 9% and no more than 10%” ethanol (158)—a 

distinction that was not particularly relevant at that time. In the Proposed Rule, however, EPA 

asks whether it should “allow E16 to E50 blends to have higher RVP levels than otherwise 

required by our regulations for gasoline.” (159) Our answer is ‘yes.’ It is important that EPA, 

consistent with the terms of the statute, treat the new mid-level ethanol blend the same as E10, 
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granting it a one-pound waiver of the RVP limit, but requiring that the gasoline portion of the 

fuel meet the applicable RVP standard. 

Because ethanol’s effect on RVP is azeotropic, and not due to a higher RVP of ethanol itself, 

adding ethanol beyond 10% is likely to lower, rather than raise, RVP. (160) Nevertheless, 

allowing the one-pound waiver would remove uncertainty for distributors and also ensure 

compliance with the statutory mandate that “fuel blends containing gasoline and 10 percent 

denatured anhydrous ethanol” (which would include any mid-level ethanol blend) receive the 

one-pound waiver. (161) The tailpipe emissions reductions achieved by a mid-level ethanol 

blend will be greater than those achieved by E10, and will more than compensate for any slight 

increase (over E0) in evaporative emissions that may occur because of the higher RVP of the 

blended fuel. (162) As a result, a mid-level ethanol splash blend would be superior to both E0 

and E10 on all counts: Its toxic, hydrocarbon, and NOx tailpipe emissions would be lower, and, 

due to the higher concentration of ethanol, its evaporative emissions would be lower as well. 

(163) 

The Agency’s requests for comment demonstrate its awareness of the benefits of a mid-level 

ethanol blend. However, approving a new certification fuel is not enough. We urge EPA to take 

the initiative to shepherd a nationwide transition to this cleaner, more efficient, renewable fuel in 

order to realize its benefits to air quality and public health, automotive performance, and 

consumer costs, while meeting the Agency’s obligation to regulate air toxics in motor vehicle 

fuel. Although critically important, a new certification fuel should be only the first step in a 

comprehensive plan to make a mid-level ethanol blend available at pumps across the country and 

to enable the production of vehicles designed to maximize its benefits. We appreciate the 

opportunity to offer such a plan, and we look forward to providing any additional information or 

assistance that might be useful to EPA as it strives to protect air quality and public health for all 

Americans. 

141 - Again, we reiterate that manufacturers themselves are powerless to make a fuel commercially 

available. EPA, in contrast, has wide authority to regulate toxic compounds in motor vehicle fuel, thereby 

ensuring that cleaner fuels are available, just as it did in the lead phase-out. In this case, EPA has 

authority—and indeed the responsibility—to mandate aromatics reductions under sections 202(l) and 211.

151 - See supra Parts III.B.1-B.2.

152 - 42 U.S.C. § 7545(h)(1).

153 - Id. § 7545(h)(1)-(2).

154 - 40 C.F.R. § 80.27(a)(2).

155 - See Proposed Tier 3 Rule, 78 Fed. Reg. at 29938 (“As the ethanol level increases, the volatility 

increase caused by blending ethanol with gasoline begins to decline, such that at E30 there is only about a 

0.5-psi RVP increase.”).

156 - See id.

157 - 42 U.S.C. § 7545(h)(4) (“Ethanol Waiver. For fuel blends containing gasoline and 10 percent 

denatured anhydrous ethanol, the Reid vapor pressure limitation under this subsection shall be one pound 

per square inch (psi) greater than the applicable Reid vapor pressure limitations established under 

paragraph (1).”).

158 - 40 C.F.R. § 80.27(d)(2); see also id. § 80.28(g)(8) (providing as a defense for a noncompliant E10 

blend that its blendstock met the RVP standard).

159 - Proposed Tier 3 Rule, 78 Fed. Reg. at 29938.

160 - See id.

161 - 42 U.S.C. § 7545 (h)(4).
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162 - See Fann, supra note 58, at 176, fig. 4 (ranking PM and VOCs according to the dollar/ton benefit of 

their respective reductions).

163 - Proposed Tier 3 Rule, 78 Fed. Reg. at 29938 (“The evaporative emission increase caused by E30 

would . . . be less than for E10.”).

Commenter: Flint Hills Resources, LP (FHR)

Regarding E51-83 for use in flexible fuel vehicles (FFV), this fuel should be defined to meet 

ASTM 5798-13, including the, maximum RVP specifications, and be required to meet the same 

sulfur and benzene standards otherwise applicable to gasoline. Also, an effective date should be 

established for the E51-83 standards and regulations. Lastly, FHR believes that formal rulesshould be developed for E16-50 use in FFVs. 

Comments to the Jeff Herzog Memorandum dated April 8, 2013: Notwithstanding the APA and 

CAA requirements to publish proposed rules within the Federal Register, FHR provides the 

following comments to the Jeff Herzog Memorandum dated April 8, 2013 posted within the 

docket (ID: EPA—HQ—OAR-2011-0135-0529): 

E51-83 Should be Defined to Meet ASTM D5798-13: FHR agrees that E51-83 for use in 

Flexible Fueled Vehicles (FFV) should be required to meet the same sulfur and benzene 

standards otherwise applicable to gasoline, as well as the Clean Air Act Section 211(f)(1) 

substantially similar provision. In addition to sulfur and benzene standards, FHR recommends 

that the definition within the draft regulatory text in §80.2(cccc) be revised to require E51-83 to 

meet the requirements of ASTM Standard Specification for Ethanol Blends for Flexible-Fuel 

Automotive Spark-Ignition Engines D5798-13. 

FHR believes that the adoption of ASTM 05798-13 would be a key supporting element to 

achieve EPA’s E51-83 objectives. ASTM D5798-13 presents performance requirements for 

ethanol fuel blends of DFE and hydrocarbon blendstock. Within ASTM D5798-13, DFE must 

meet the requirements of ASTM D4806, and the hydrocarbon blendstock may be composed of 

unleaded gasoline, gasoline blendstock for oxygenate blending (BOB), natural gasoline or other 

hydrocarbons in the gasoline boiling range. ASTM 05798-13 also sets further requirements for 

hydrocarbon blendstock properties, including maximum distillation end point, oxidation stability, 

copper strip corrosion, and silver strip corrosion. 

Different Requirements Should be Provided for E51-83 Refiners and Blenders: FHR agrees that 

E51-83 refiners should be subject to the full responsibilities of a refiner (e.g. registration, batch 

sampling, testing, and reporting obligations), as described in Option 1 within the Herzog 

Memorandum. FHR also agrees that E51-83 blenders should be exempt from the sampling, 

testing, and reporting obligations of refiners, when using gasoline, gasoline blendstocks for 

oxygenate blending, DFE, natural gas liquids (NGL) and butane that meet certain specifications, 

as outlined in Option 2 within the Herzog Memorandum. 

FHR agrees with this two-option approach, as a means to not restrict refiners or downstream 

blenders from choosing maximum blending flexibility by meeting the more stringent refiner 

requirements, as outlined in Option 1. FHR also believes that E51-83 blenders should be required 

to meet the 95 ppm downstream per-gallon cap sulfur standard included within §80.1604(b), 
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instead of the 80 ppm per-gallon cap standard sulfur of §80.1603(a)(2), as incorporated within 

§80.1608(b)(1). 

As means of further streamlining the requirements of Option 1, FHR recommends that EPA 

consider adopting batch sampling, testing, and reporting obligations for batches of E51-83 

hydrocarbon blendstock, as defined within ASTM 05798-13, that include the test results obtained 

from testing a hand blend with DFE, similar to the RBOB/RFG requirements of §80.69(a). 

Under these circumstances, a refiner could manufacture, sample and test any batch quantity of 

E51-83 blendstock , blend with DFE into multiple tank trucks at a refinery loading rack, and 

avoid the requirement to sample, test and report each tank truck. 

E51-83 Should Meet the Reid Vapor Pressure (RVP) Specifications within ASTM D5798-13: 

ASTM D5798-13 sets maximum RVP requirements for ethanol fuel blends for FFV that vary 

only slightly from EPA’s maximum RVP requirements for gasoline within §80.27(a)(2). As 

such, FHR believes that EPA should adopt the maximum RVP requirements of ASTM D5798-13 

within the draft regulatory text for Option 1 E51-83 refiners in §80.1608(c)(6) and Option 2 E51-

83 blenders in §80.1608(b)(4). 

In addition, FHR believes that EPA does not need to impose minimum volatility standards for 

E51-83. By defining E51-83 to meet the requirements of ASTMD5798-13, EPA would be 

adopting the minimum RVP specifications within ASTM D5798-13 by reference. 

E51-83 Should Meet the Benzene Standards Otherwise Applicable to Gasoline: FHR has 

identified a concern with the suggested 0.20 volume percent benzene cap for E51-83 refiners and 

E51-83 blenders within the draft regulatory text in §80.1608(c)(3) and §80.1608(b)(2), 

respectively. To resolve this issue, FHR recommends that E51-83 refiners and E51-83 blenders 

be required to meet the same benzene standards otherwise applicable to gasoline within 

§80.1230. 

Requiring E51-83 to meet a 0.20 volume percent benzene cap would effectively preclude the 

blending of gasoline blendstock to manufacture E51-83. As EPA states, refiners and importers of 

gasoline are subject to a 0.62 volume percent annual average and 1.3 volume percent maximum 

average benzene standards. Furthermore, natural gasoline, used as a DFE denaturant, typically 

contains in excess of 1 volume percent benzene. As an example, E51-83 composed of 49 percent 

gasoline blendstock with 1.3 volume percent benzene and 0.01 percent natural gasoline 

denaturant with 1 volume percent benzene could have a resulting benzene content exceeding 

0.65 volume percent. In another example, E51-83 composed of 17 percent gasoline blendstock 

with 1.3 volume percent benzene and 1.7 percent natural gasoline denaturant with 1 volume 

percent benzene could have a resulting benzene content exceeding 0.24 volume percent. 

Therefore, the setting of a 0.20 volume percent benzene cap could interfere with the expansion of 

E51-83 into the marketplace by preventing blends at the both the upper and lower range of the 

allowable ethanol content with gasoline blendstock meeting the requirements of §80.1230. 

Furthermore, requiring natural gasoline for use by E51-83 blenders to meet a 0.03 volume 

percent benzene cap within §80.1612(a)(4), or the 0.20 volume percent stated within the 

memorandum, would effectively preclude the use of natural gasoline, as a hydrocarbon 
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blendstock, to manufacture E51-83. As previously stated, natural gasoline typically contains 1 

volume percent benzene, and as stated within the memorandum, could be as high as 2 volume 

percent benzene. FHR believes that it is reasonable for natural gasoline blended into E51-83 to 

be required to meet a maximum benzene standard of 1.1 volume percent within §80.1612(a)(4) 

and a maximum sulfur standard of 20 ppm within §80.1612(a)(3). 

An Effective Date Should be Set for E51-83: Apart from the gasoline sulfur implementation 

dates via §80.1603(a), sections 80.1608 and 80.1611 do not specify an effective date for the 

standards and requirements for E51-83. FHR infers the effective date to be sometime in 2017, 

but requests this clarification be added into the regulation. 

Formal Rules Should be Developed for E16-50 Use in Flexible Fuel Vehicles: FHR agrees that 

E16-50 ethanol blends for use only in FFV should meet the same sulfur, RVP, and benzene 

standards otherwise applicable to gasoline. FHR also agrees that EPA should treat E16-50 as 

gasoline under current regulations. However, in FHR’s opinion, this action would require formal 

rulemaking, including a waiver from the substantially similar requirements, explicitly listing 

E16-50 in §80.1601(a), and providing a definition within §80.2. 

1- Herzog, J. (January 2012). Possible Approach to Fuel Quality Standards for Fuels Used in FlexibleFuel Automotive Spark-Ignition Vehicles (FFVs), Memorandum to the docket. The memorandum is 

referenced in footnote 388 of the pre-publication proposed rule; however, the footnote reference is to a 

memorandum dated January 2012 but the memorandum in the docket is dated April 8, 2013. Further, this 

memorandum was not in the docket at the time the proposed rules were announced on EPA’s website.

2 - United States Code, Title 5, Chapter 5

3 - 5 USC 552(a)(1)

Commenter: Growth Energy

In particular, Growth Energy fully supports the treatment of midlevel ethanol blends (E16-50) as 

alternative fuels.

Higher Ethanol Blends Improve Air Quality and Warrant Consideration for Higher Reid 

Vapor Pressure Limits: In the proposal, EPA seeks comment on whether it is appropriate to 

allow higher RVP limits for midlevel in-use ethanol blends (E16-E50). Currently, EPA is 

required to limit gasoline to 9.0 pounds per square inch (psi) except in areas where further 

emission control is required, and E10 currently has a 1 psi waiver allowing it to rise to 10.0 psi. 

Any review of RVP and ethanol blends shows that RVP decreases as ethanol is added and that 

the highest RVP occurs with an E10 blend (estimated RVP curve below) [Figure can be found on 

p. 8 of Docket number EPA-HQ-OAR-2011-0135-4681-A3]. As ethanol increases, RVP 

decreases and better air quality is achieved. Therefore it is certainly appropriate and Growth 

Energy would fully support higher RVP limits for all ethanol blends above E10. It would be 

counter to the intent of this proposed rule to continue to provide a waiver for E10 while requiring 

blends above E10 which demonstrate better air quality not to enjoy the same treatment. 

Specifically, EPA sought comment on the regulation of midlevel and highlevel ethanol blends 

(E16-E85) as an alternative fuel family as discussed in the Herzog memo to the docket (Jeff 

Herzog, “Possible Approach to Fuel Quality Standards for Fuel Used in Flexible-Fuel 
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Automotive Spark-Ignition Vehicles (FFVs)”). Growth Energy fully supports the treatment of 

ethanol blends above E15 as an alternative fuel family rather than as gasoline and feels as though 

EPA can use its authority under 211(C) to take ethanol blends’ lower RVP relative to E10 

gasoline to provide similar RVP leeway as that given to gasoline. Additionally, because 

evaporative emissions from the current vehicle fleet are already well controlled and will be 

further controlled through the Tier 3 evaporative emissions standards, Growth Energy believes 

that a similar 1 psi waiver should also be extended to gasoline blends above E10 as well as 

midlevel ethanol blends. 

Benzene limits for ethanol blends must take into account the gasoline blended with ethanol. EPA 

believes “it may be possible to set the benzene standard for E51-83 at a 0.20 volume percent cap 

or even lower without imposing any burden rather than implementing an average annual benzene 

standard similar to that for gasoline.” (Herzog, FQS for FFVs, p. 5) Gasoline has 0.62 volume 

percent average maximum benzene content. 

A benzene cap of 0.20 percent on ethanol blends would create a tremendous burden on blenders 

and could render certain production impossible. For instance, an E51 blend composed of 51 

percent DFE and 49 percent certified gasoline would likely have a benzene content of 0.31 

percent as the gasoline would bring 0.62 percent benzene to the mixture. This mixture would not 

meet the regulatory requirements. 

Under the proposed approach, E51-83 could only exist as E75-83 with DFE at a 0.06 percent 

benzene and gasoline at 0.62 percent benzene. Higher benzene levels in the gasoline due to 

averaging would further limit the hydrocarbon content of this fuel as well as the RVP and cold 

start capability in cold weather. It is imperative that EPA provide a higher benzene limit to 

account for the gasoline blended with ethanol. Growth Energy feels that EPA should set this 

benzene standard at 0.62 volume percent, identical to the gasoline limit. 

We agree with EPA that addressing RVP in blends does not require batch testing. EPA states that 

“For blenders that use only gasoline, BOB’s, and DFE to produce E51-83, demonstration of 

compliance with the maximum RVP standard under consideration could be accomplished by 

retention of Product Transfer Documents for the blendstocks.” 

Additionally, EPA raises the issue of whether the SAE “Model for Estimating Vapor Pressures 

of Commingled Ethanol Fuels” is adequate to avoid testing for NGLs and refinery naphthas for 

RVP.17 Growth Energy agrees that the SAE model referenced in the FQS for FFVs memo 

should be adequate to avoid testing for NGLs and refinery naphthas for RVP.18 

EPA states that “Given the proposal in the Tier 3 NPRM to limit the denaturants that can be used 

to manufacture DFE to NGL, gasoline, and BOBs, and the narrow range in denaturant 

concentration, we believe that the RVP of different batches DFE would not vary substantially. 

Therefore, we currently do not believe that deliveries of new batches of DFE into the storage 

tank used to produce E51-83 would necessitate a return to per batch testing.” We agree that the 

variability of the ethanol RVP would not vary substantially, and batch testing should not be 

required, with a 5 percent denaturant cap.20 
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EPA’s streamlined “Blender Option” requirements should be the default regulations for E16-E85 

production (as opposed to full refiner responsibilities). The Tier 3 rule appropriately recognizes 

that ethanol blending is of central importance to our nation’s transportation fuel supply and 

accomplishing key environmental and energy security goals. To achieve these goals and 

maintain a robust domestic transportation fuel supply, it is critical that EPA design its regulations 

to facilitate the production and blending of ethanol. 

EPA discusses its possible approaches to the regulation of ethanol (and vehicles that use ethanol) 

in the Proposed Rule, including the section “Standards for Fuel Used in Flexible Fueled 

Vehicles.” This section then references a detailed memo to the docket, the FQS for FFVs Memo. 

The FQS for FFVs memo outlines two options for regulating manufacturers of E51-E83. Growth 

Energy strongly supports “Option 2: Treatment as a Blender” (the “Blender Option”) as the 

default option. Under this Blender Option, EPA states that E51-E83 producers can reduce their 

regulatory burden if they only use blendstocks that meet certain specifications that would ensure 

sulfur and benzene does not exceed appropriate amounts.12 

More specifically, under this Blender Option, EPA proposes generally to limit blendstocks for 

ethanol blends to gasoline, BOBs, and DFE, as well as natural gas liquids (NGLs) and butane if 

they are produced to certain standards. Under this Blender Option, the finished E51-83 would be 

subject to the proposed downstream sulfur cap for gasoline of either 65 ppm or 95 ppm. A 

benzene limit would also apply to the finished blend (as discussed above).

Growth Energy agrees that testing of final blends would not be needed as the DFE and 

blendstocks are regulated individually for sulfur and benzene (and RVP issues can be handled in 

a streamlined fashion as well). 

Growth Energy also believes that the Blender Option requirements could apply equally to E16-

E50 as well as E51-E83. The FQS for FFVs memo also notes that “the draft regulations written 

to address E5183 might be modified to cover E16-50 blends.” Growth Energy believes that this 

Blender Option can be applied across all ethanol blended fuels from E16-E85. If EPA considers 

it necessary to further delineate midlevel ethanol blending, we suggest that applicable ASTM 

standards already provide a suitable approach. In particular, ASTM Standard D7794 allows 

midlevel ethanol blends only to be created from a mixture of gasoline and DFE, or gasoline and 

E85.15 Thus, the constituents of midlevel ethanol blends (gasoline, DFE, and E85) are already 

controlled. This is consistent with the streamlined “Blender Option” that avoids batch testing for 

blends when the constituents of those blends are already controlled. 

Under the Blender Option, gasoline blendstocks should be allowed for blending (in addition to 

NGLs and butane) as long as they meet adequate specifications. Light straight run naphtha, 

hydrotreated naphthas, and hydrotreated natural gasoline are potential streams to consider. These 

gasoline blendstocks could be subject to the same sulfur and benzene specifications as NGLs and 

butane and should be allowed as blendstocks for ethanol blends. 

Growth Energy supports facilitating the use of NGLs under the Blender Option in the production 

of ethanol blends. We do not believe that any EPA limits on the volume of NGL used as a 
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blendstock are necessary for ethanol blends (E51-E83). For midlevel ethanol blends (E16-E50), 

if EPA considers that some NGL limits are necessary, we would suggest that applicable ASTM 

standards already effectively limit the NGL content in midlevel ethanol blends. In particular, as 

noted above, ASTM Standard D7794 allows midlevel ethanol blends only to be created from a 

mixture of gasoline and DFE, or gasoline and high level ethanol blends (E51-E83). The amount 

of NGLs allowed in these constituent products are already controlled. Therefore, the volume of 

NGL in midlevel ethanol blends can effectively be no greater than what is already contained in 

approved components of a midlevel ethanol blend. 

Furthermore, we respond to the following statements by EPA regarding NGLs under the Blender 

Option: 

Production “using NGL blendstocks would require that the NGL blendstock, like butane, 

meet a 10-ppm per-gallon sulfur cap.”

o We agree that NGL (or gasoline blendstocks such as hydrotreated refinery 

streams) used for blending E16-E83 should meet the proposed 10 ppm sulfur cap 

under the Blender Option and therefore avoid burdensome batch testing 

requirements for blending.

EPA notes that “Similar to the envisioned 0.20 volume percent benzene cap for butane, 

we would look to implement a 0.20 volume percent benzene cap standard for NGL rather 

than an average standard in order to simplify the regulatory requirements.” 

o A benzene cap of 0.20 percent for NGLs is too restrictive and may be impractical 

to meet. The benzene standard for NGLs should be 0.62 percent benzene similar 

to unleaded gasoline. Therefore, this NGL stream or gasoline could be used in the 

blend with no detrimental effect to the finished fuel since the DFE in which it is 

blended will have little to no benzene.

“Since NGL properties from different sources can vary widely ... we may also need to 

consider restricting the sources of NGL to natural gas liquids fractionation facilities and 

natural gas processing plants to ensure an appropriate level of quality control.’

EPA should maintain a provision for an alternative NGL source to allow for 

hydrotreated streams or refinery streams that meet the same criteria [i.e., benzene 

and sulfur limits]. Refineries (including where hydrotreating takes place) can provide the 

same or superior quality control as NGL fractionation facilities and natural gas 

processing plants. 

“Stakeholders have stated that as additive concentration diminishes due to dilution with DFE, 

there is a point where the presence of a deposit control additive ceases to be beneficial and can 

actually contribute to deposit formation. In light of this, it may be appropriate to remove the 

requirement that the gasoline portion of E51-83 and perhaps E16-50 must contain a deposit 

control additive until the specific deposit control needs of these blends can be evaluated.” 

o We support removal of the requirement that the gasoline portion of E51-E83 must contain a 

deposit control additive until the specific deposit control needs of these blends can be evaluated.

A similar approach may be warranted for E16-E50. 
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EPA should not unduly regulate E16-E83 blendstocks. EPA states that “Currently, only ... 

RBOBs ... and gasoline ... are used to manufacture E51-83.” This is inaccurate. Gasoline 

blendstocks and natural gasoline can also be used in E51-E85 today.26 

Some ethanol producers may wish to use non-standard blendstocks, which they should maintain 

the option to do as long as the end product meets appropriate specifications. Ethanol producers 

should have the option to do so, if they opt to undertake broader “refiner” responsibilities. These 

“refiner” responsibilities could require batch testing of the end product, and some ethanol 

producers may consider this extra cost and burden appropriate.27 

EPA’s proposed regulations unduly restrict using NGL as a denaturant or blendstock. A 

requirement to “Certify that the NGL was derived solely of from [sic] natural gas liquids 

fractionation facilities and natural gas processing plants” is too narrow. As noted above, EPA 

should include refineries (including hydrotreating) as potential hydrocarbon stream sources as 

long as blendstocks meet certain requirements (i.e., benzene and sulfur limits). 

A requirement to demonstrate “that the benzene content of each production batch of NGL is not 

greater than 0.03 volume percent” is too restrictive. This specification is unrealistic, and it is 

unclear whether a product that meets this specification even exists in any significant commercial 

quantities. For instance, this specification is 20 times more stringent than gasoline and wouldn’t 

apply to NGLs blended directly into unleaded gasoline. [Even California ethanol specifications 

allow benzene content up to 0.06 volume percent in DFE. Therefore, the resultant specification 

allows NGL with benzene levels up to 2.4 volume percent.] 

A prohibition that “NGL and E51-83 made from NGL cannot be sold as gasoline or E16 or be 

commingled with gasoline or E16-50 and subsequently sold as gasoline or E16-50” is unduly 

restrictive. This prohibition on commingling E51-83 made with NGL with MLEBs would unduly 

limit the ability for retail stations to provide E16-E83 fuels, especially if they employ blender 

pumps. Alternatively, EPA should follow ASTM requirements as stated in standards D4814, 

D4806, D5798 and standard practice D7794. 

12 Some ethanol producers may wish to use non-standard blendstocks, which they should maintain the 

option to do as long as the end product meets appropriate specifications. Ethanol producers should have 

the option to do so, if they opt to undertake broader “refiner” responsibilities. These “refiner” 

responsibilities could require batch testing of the end product, and some ethanol producers may consider 

this extra cost and burden appropriate.

15 See ASTM D7794-12 (D7794) “Standard Practice for Blending Mid-Level Ethanol Fuel Blends for 

Flexible-Fuel Vehicles with Automotive Spark-Ignition Engines.” This standard incorporates by reference 

ASTM standards governing the permissible constituents of MLEBs including one for gasoline (D4814), 

as well as ASTM D4806-12 (“Standard Specification for Denatured Fuel Ethanol for Blending with 

Gasolines for Use as Automotive Spark-Ignition Fuel”) (DFE) and ASTM D5798-12 (“Standard 

Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition Engines”) (HLEBs).

17 By way of background, EPA stated “If NGL and/or butane were used to manufacture E51-83, 

demonstration of compliance with a maximum RVP requirement could not be accomplished merely by 

retention of [product transfer documents (PTDs)] indicating that blendstocks were produced subject to 

applicable standards.... However, it may be possible to avoid sampling and testing for RVP as well. RVP 

models exist that could perhaps be developed further to avoid the need for sampling and testing for RVP 

when NGL or butane were used, but they are not yet applicable to these blends.” Id.
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18 See id. at 7 n. 22 (referencing SAE paper 2007-01-4006, “A Model for Estimating the Vapor Pressures 

of Commingled Ethanol Fuels.”).

20 [By way of example, 5 percent denaturant would create a .75 psi difference between a 9 psi and 14.5 

psi denaturant in DFE. Either blend would change the E85 RVP by 0.5 psi or less according to the model 

in SAE paper 2007-01-4006. This minor impact would not cause any concerns for E85 (which already 

have low volatility), and the impact on MLEBs from the RVP of denaturant would be even smaller due to 

the overall smaller proportional share of denaturant in the overall blend (i.e., 5 percent denaturant in an 

E30 blend would be only 1.5 percent of the total fuel mixture).]

26 See e.g., ASTM standard for HLEBs, ASTM D5798-12.

27 Under either the Blender Option or the more stringent refiner option (which would regulate ethanol 

producers similar to gasoline refiners), the resulting E16-E83 “produced would be required to meet the 

downstream sulfur, RVP, and a benzene per-gallon cap standard in order to ensure emission performance 

over the life of the vehicles that use it.” FQS for FFVs Memo, supra, at 4.

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

Currently, only RFG, conventional gasoline, and RBOB may be used to produce gasoline with 

high concentrations of ethanol – E51 to E83. EPA recognizes that there will be a greater need 

for outlets for ethanol as the Renewable Fuel Standard Mandates increase. Therefore, EPA is 

encouraging the use of E51 to E83 fuels. EPA would like to remove regulatory obstacles to its 

production while ensuring that the product meets the fuel quality requirements needed to 

maintain vehicle emission performance. 

EPA has stated in the Preamble to the proposed regulations that the exclusive use of RFG, 

conventional gasoline, and RBOB in the production of such higher ethanol-concentrated blends 

may interfere with the expansion of the E51 to E83 market. EPA notes that with higher ethanolconcentration fuels, blenders cannot meet volatility specifications set by ASTM for cold start 

performance. Therefore, EPA is proposing to apply to E51 to E83 blends, the same sulfur, RVP, 

and benzene standards applicable to gasoline as well as the “substantially similar” rule 

requirements. Application of such regulations would allow the production of E51 to E83 using 

butane and natural gasoline liquids, which, in turn, would allow the blends to meet ASTM 

volatility specifications. In addition, because butane is a relatively inexpensive component, its 

use should reduce the cost of these higher ethanol-concentration blends, making the final product 

– E51 to E83 – more attractive to consumers. 

While Members of the Association understand EPA’s desire to expand the E51 to E83 blend 

market, it is essential that EPA ensure that whatever actions are taken, the authority for use of a 

one pound RVP waiver during the summer months be retained. As more and more ethanol is 

added to blends, the waiver becomes more important. If it were eliminated, refiners would have 

great difficulty meeting RVP standards, and would have to use more costly components with 

lower RVP (e.g., alkylates) in their gasoline production. Such actions could substantially 

increase the ultimate fuel price to consumers.

Recommendation: Accordingly, if EPA decides to amend the regulations to expand the E51 to 

E83 blend market, it should also ensure that the RVP waiver for summer months is preserved.
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While encouraging the use of higher ethanol-concentration blends – E51 to E83 – preserve the 

one pound RVP waiver during the summer months; 

Commenter: Magellan Midstream Partners, L.P.

Magellan Comment — we have developed an Ethanol Flex Fuel (EFF) program which 

exclusively utilizes gasoline as the hydrocarbon portion of the EFF mixture. All EFF distributed 

from Magellan’s terminals meet ASTM-5798-11 everyday of the year. It is indeed feasible to 

utilize gasoline as the sole hydrocarbon component in producing EFF. Our EFF program meets 

the quality expectations of our customers, the automobile industry and others. 

Generally, we applaud EPA for taking the step to regulate higher level ethanol blends such as 

EFF. This regulatory action is overdue. Magellan agrees that EFF should also be required to 

meet the same sulfur, Reid Vapor Pressure and benzene standards which are applicable to 

gasoline and the interpretive rule defining the phrase ‘substantially similar’ in CAA section 

211(0(1) (i.e., contain only carbon, hydrogen, oxygen, nitrogen, and sulfur) that apply to any fuel 

used in an FFV requirement. While we appreciate EPA’s proposals to expand the use of natural 

gas liquids (NGLs) as the hydrocarbon portion of the EFF blend, this increases the potential for 

the development of EFF which may not meet stakeholder expectations unless stringent standards 

are established. However, we do not believe the use of NGLs should be permitted in EFF until 

adequate testing is complete and appropriate standards are established. 

Although NGLs have been used in gasoline, they have not been used for the production of EFF, 

or have not at least been tested under controlled conditions to assess performance and establish 

specifications. We do not believe EPA should proceed with rules which allow an untested fuel in 

the market place. The use of very light hydrocarbons should be fully tested and incorporated into 

specifications and regulations only after they have been demonstrated to provide satisfactory 

performance. In our view, the use of NGLs should not be allowed as the hydrocarbon piece of 

EFF solely to reduce the cost of the blend when compared to the utilization of gasoline. 

We have reviewed EPA’s options as explained in the April 8, 2013 memorandum to the docket. 

Option 1 requires the EFF producer (i.e. denatured fuel ethanol producers) to assume the full 

responsibilities of a refiner. While we believe the EFF producer should be required to register 

and report as a refiner, EFF producers who may be allowed to blend NGLs in the future and 

refiners currently blending NGLs into gasoline should be allowed to utilize the additional 

flexibility provided in Option 2 as long as the respective hydrocarbon components meet well 

established specifications. 

Compliance burden when blending NGLs into Gasoline / Blendstock Representation: Magellan 

Comment — as stated above, we do not believe EPA should permit the use of NGLs as the 

hydrocarbon portion of EFF until adequate testing is complete. Once testing is complete and 

satisfactory standards have been established, we would support the use of NGLs in EFF. We 

applaud EPA’s options raised in the EFF preamble regarding the compliance burden normally 

associated with refiner sampling and reporting. We believe this approach should promptly be 

made available to refiners producing gasoline using NGL blendstocks in gasoline. 
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To this end, we propose the following Blendstock Specifications for gasoline blenders: We 

believe adoption of these specifications will allow additional flexibility for blending which 

would lower the overall cost impact of the Tier 3 fuel requirements in general. 

Lastly we agree that it is important to reduce the compliance burden for blending natural 

gasoline into ethanol as a denaturant, just as it is for gasoline blenders. As EPA considers 

regulatory compliance requirements for ethanol and flex fuels, as a matter of fairness, we 

encourage the agency to provide similar compliance requirements for all fuel production from 

gasoline range blend stocks.

Commenter: Manufacturers of Emission Controls Association (MECA)

MECA also supports defining fuel sulfur average limits or caps on any alternative transportation 

fuels (e.g., blends of alcohols with gasoline, natural gas) that are consistent with the proposed 10 

ppm national average for gasoline or the existing 15 ppm national sulfur cap on diesel fuel. 

Commenter: Marathon Petroleum Company LP (MPC)

Standards for Mid-Level Ethanol Blends (E16-50): MPC agrees that Mid-Level Ethanol Blends 

(E16-50) for use in FFV should meet the same sulfur, RVP, and benzene standards otherwise 

applicable to gasoline. MPC does not agree that EPA should treat E16-50 as gasoline under 

current regulations. In MPC’s view, this action would require formal rulemaking with a waiver 

from the substantially similar requirements. 

EPA is proposing that gasoline deposit control requirements be removed from the E16-50 and 

E51-83 fuels. MPC believes that it is in the best interest of the consumer to maintain a deposit 

control requirement for all spark-ignition fuels at a minimum level to protect the engines of 

consumers and to reduce air emissions. 

Standards for E51-83: EPA’s preamble to the proposed Tier 3 regulations references a separate 

memorandum25 that includes additional proposed regulations for which EPA seeks comments. 

These additional regulations include prescribing new requirements for E51- E83 for key fuel 

properties such as sulfur, RVP, and benzene. While MPC may support EPA’s effort to develop 

regulations for E51-E83, the process EPA used to inform the regulated community runs afoul of 

the federal Administrative Procedures Act (APA) and the federal Clean Air Act (CAA). 

The APA is clear that EPA’s forum for informing the public of substantive rules, amendments, 

and revisions is through the Federal Register. Further, the APA states “except to the extent that a 

person has actual and timely notice of the terms thereof, a person may not in any manner be 

required to resort to, or be adversely affected by, a matter required to be published in the Federal 

Register and not so published.” 

Section 307(d)(3) of the CAA echoes the requirement for proposed rules to be published in the 

Federal Register. Among other things, the notice must “specify the period available for public 

comment.” In addition, at the time of publication, there must be a publicly available docket that 

includes: (1) the factual data on which the proposal is based; (2) an explanation of how EPA 
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collected and analyzed the data; and (3) an explanation of the major legal interpretations and 

policy considerations underlying the proposal. 

In the instant matter, EPA describes and seeks comment on very significant potential changes to 

the regulations. EPA is required, by law, to publish such a proposal in the Federal Register. 

Posting on EPA website or including within the rulemaking docket is not an option – publication 

in the Federal Register means publication in the Federal Register. EPA must include all proposed 

changes in the proposed rule. References to documents external to the proposed rule do not give 

the regulated community and public the opportunity to which it is entitled to generate informed 

and timely comments regarding the proposed rule. 

Notwithstanding the APA requirement to publish proposed rules within the Federal Register, 

MPC would like to provide the following comments to the Jeff Herzog Memorandum dated 

April 8, 2013 that is posted within the docket (ID: EPA–HQ–OAR–2011–0135-0529): 

MPC agrees that E51-83 for use in Flexible Fueled Vehicles (FFV) should be required to meet 

the same sulfur, maximum Reid Vapor Pressure (RVP), and benzene standards otherwise 

applicable to gasoline, as well as the Clean Air Act Section 211(f)(1) substantially similar 

provision. EPA should also allow for the use of butane or other natural gas liquids (e.g. pentane, 

natural gasoline, etc.) to manufacture E51-83 with sufficient volatility to meet the ASTM D5798 

specifications. MPC does not support limits on specific components, but does support adoption 

of reasonable standards to facilitate blending. 

However MPC has identified a serious concern with the suggested 0.20 volume percent benzene 

cap for E51-83. Requiring E51-83 to meet a 0.20 volume percent benzene cap would effectively 

preclude the blending of gasoline blendstock and natural gasoline to manufacture E51-83. As 

EPA states, refiners and importers of gasoline are subject to a 0.62 volume percent annual 

average and 1.3 volume percent maximum average benzene standard. Furthermore, natural 

gasoline typically contains in excess of 1 volume percent benzene. As an example, E5183 

composed of 49 percent gasoline blendstock with 1.3 volume percent benzene and 0.01 percent 

natural gasoline denaturant with 1 volume percent benzene could have a resulting benzene 

content exceeding 0.65 volume percent. In another example, E51-83 composed of 17 percent 

gasoline blendstock with 1.3 volume percent benzene and 1.7 percent natural gasoline denaturant 

with 1 volume percent benzene could have a resulting benzene content exceeding 0.24 volume 

percent. Therefore, the setting of a 0.20 volume percent benzene cap would interfere with the 

expansion of E51-83 into the marketplace by preventing blends at the both the upper and lower 

range of the allowable ethanol content. To resolve this issue, MPC recommends that E51-83 be 

required to meet the same benzene standards applicable to gasoline. 

MPC support s EPA’s suggested requirement that compliance with the Section 211(f)(1) 

substantially similar provision would be effectively achieved by ensuring that E51-83 be 

composed solely of carbon, hydrogen, nitrogen, oxygen, and sulfur. 

MPC agrees that manufacturers of E51-83 for use in FFV should also be subject to the full 

responsibilities of a refiner (e.g. registration; batch sampling and testing; and reporting 

obligations), which is outlined as Option 1 within the Herzog Memorandum. However, if EPA 
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wishes, as a second option, to allow oxygenate blenders to be exempt from the sampling, testing 

and reporting obligations of refiners, oxygenate blenders should be required to only use gasoline 

blendstocks, denatured fuel ethanol, natural gas liquids (NGL) and butane that meet certain 

specifications. MPC agrees with this two-option approach as a means to not restrict refiners or 

oxygenate blenders from choosing maximum blending flexibility by meeting the more stringent 

requirements, as outlined within Option 1. MPC also agrees that any resulting E51-83 should 

also be required to meet the downstream sulfur, RVP and benzene per-gallon cap standard. 

MPC agrees that it may be possible to develop a calculative approach for E51-83 blenders to 

determine RVP and avoid sampling and testing. We agree that testing may be required for some 

period of time when a blender receives a new batch of gasoline blendstock. We also agree that 

RVP of different batches of DFE would not vary significantly due to TTB requirements related 

to denaturants and denaturant percentages, along with RFS2 requirements related to denaturant 

concentrations for RIN generation. 

MPC agrees that butane used for E51-83 blending should meet the same standards as specified 

for butane blended into gasoline at a terminal. However, the limits on other components in E51-

83 should be restricted to their total contribution toward regulated properties on the final fuel, not 

the same limits imposed on the components. Sources for NGLs should not be limited, provided 

the NGL conforms to the requirements. 

Although MPC does not believe that the Herzog Memorandum is a part of the proposed Tier 3 

regulations since it has not been published in the Federal Register, MPC provides the following 

specific comments to the draft regulatory text:

80.2 Definitions: New paragraph 80.2(cccc), which will provide the definition for E51-83, 

includes the reference to the ASTM D5798-11 standard for ethanol fuel blends for FFV’s. This 

reference should be updated to reflect the currently published version ASTM D5798-13 and 

should be updated further if a newer is adopted by ASTM.

80.1601 Fuels subject to the provisions of this subpart: EPA proposes adding item 80.1601(a)(4) 

to explicitly include E51-83 as being subject to the provisions of Subpart O regarding gasoline 

sulfur. However, we do not see an explicit addition to also include E16-50. Assuming EPA 

believes Subpart O regarding gasoline sulfur should also apply to E16-50, then E16-50 should 

explicitly also be listed in 80.1601(a). 

Under, 80.1601(b)(2), “California gasoline as defined in §80.1600 subject to the provisions of 

§80.1654” is not subject to the standards and requirements of Subpart O. It is unclear if and how 

the Subpart O requirements apply to E51-83 and/or E16-50 sold in California. 

80.1608 Standards and requirements for E51-83: Apart from the sulfur dates via the requirements 

in 80.1603(a)(2), paragraph 80.1608 does not specify an effective date for the standards and 

requirements for E51-83. EPA needs to insert a clear effective date for all of the standards and 

requirements for E5183 in 80.1608. We infer this is sometime in 2017, but seek this clarity be 

added into the regulation. 
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80.1608(b)(2) as proposed sets the maximum benzene content of each batch of E51-83 at 0.20 

volume percent maximum. This benzene limit is too low, because it is inconsistent with EPA’s 

clear intent to allow E51-83 blenders to manufacture E51-83 using gasoline, gasoline 

blendstocks for oxygenate blending, denatured fuel ethanol, natural gas liquids, and/or butane 

per 80.1611. EPA needs to eliminate the explicit benzene limit in E51-83, when a blender 

manufactures this fuel under the provisions of 80.1611. Otherwise, EPA needs to increase the 

explicit benzene limit to reflect EPA’s intent to allow E85 production using compliant RFG, 

RBOB, CG, and/or CBOB. 

Section 80.1608(b)(4) listing the RVP requirements for E51-83 contains the typographical error 

“80.1627(a)(2)” when “80.27(a)(2) is intended by EPA. 

EPA should clarify in 80.1608(b)(4) where it requires that the Reid Vapor Pressure of “each 

batch” of E51-83 must comply with same standards applicable for gasoline in 80.27(a)(2) that 

being a “batch requirement” this requirement only applies to E51-83 blenders. However, if EPA 

also intends for the RVP requirements to be applicable during the “high ozone season” from June 

1

st through September 15th of each year at retail sites, then EPA has to recognize and address that 

the potentially far slower turnover of E51-83 inventory at retail sites (relative to gasoline) may 

make an RVP requirement at retail sites infeasible and dissuade retailers from offering E51-83. 

EPA should note that ASTM recognized and addressed this issue of potentially slow moving 

E51-83 at retail sites by exempting the E51-83 at a retail site from ASTM’s seasonal RVP 

requirements in ASTM’s “E51-83” standard D5798 Table 2 with note1 as follows (emphasis 

added), 

“This schedule, subject to agreement between the purchaser and the seller, denotes the vapor 

pressure class of the fuel at the time and place of bulk delivery to fuel-dispensing facilities for the 

end user. Shipments should anticipate this schedule.” 

80.1608(c)(3) provides the benzene standard for E51-83 when it is manufactured by a party that 

does not qualify as an E51-83 blender:

1. Similar to our comments regarding the 0.20 vol% benzene limit for E51-83 blenders in 

80.1608(b)(2) being too low. 0.20 vol% benzene listed in 80.1608(c)(3) for E51-83 

“refiners” is also too low and should be revised consistent with our recommendations for 

E51-83 blenders. 

2. We believe “80.1632” is a typographical error with regard to the test requirements for 

benzene in E51-83 produced by a “refiner”. We believe EPA means and should correct 

this to “80.1630” which addresses test requirements. 

80.1611 Blended E51-83 requirements: EPA needs to insert a clear effective date for the blended 

E51-83 requirements in 80.1611. We infer this is sometime in 2017, but seek this clarity be 

added into the regulation. 

As proposed by EPA, 80.1611(a) and (b) require that only RFG or RBOB be used as the gasoline 

or gasoline blendstock for oxygenate blending in E51-83 intended for sale in RFG areas. EPA 

has not provided a basis for this limitation based on air quality impact. Absent EPA providing a 
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reasonable basis, these requirements should be deleted from EPA’s proposed rules, allowing 

conventional gasoline and/or CBOB to be used as well for E51-83 in RFG areas. 

80.1612 Standards and requirements for natural gas liquids blendstock used by E51-83 blenders: 

80.1612(b) as proposed includes a prohibition on using E51-83 made from NGL in a blend with 

gasoline to make E16-50. We do not understand EPA’s logic in this prohibition and ask that EPA 

explain its reasoning further. 

80.1662 Liability for violations under subpart 0: For a sulfur cap standard violation in 

80.1660(b), paragraph 80.1662(a)(5) includes a branded refiner/importer liability as follows 

(emphasis added),

“Branded refiner/importer liability. Any refiner or importer whose corporate, trade, or brand 

name, or whose marketing subsidiary’s corporate, trade, or brand name appeared at a facility

where a violation of §80.1660(b) occurred, is deemed in violation of §80.1660(b).” 

However, this branded refiner/importer liability is too broad when EPA is now proposing to 

further expand the sulfur cap requirements in 80.1660(b) to include E16-50 and E5183 fuels sold 

at retail sites. At retail, the branded refinery has no control on the retailer who might 

independently make these product offerings from source of his/her own choosing. Branded 

refiners should not be liable in these cases simply because their brand name “appeared at a 

facility”, especially in the case where the branded refiner contractually required the retailer to

identify at the dispenser that the E16-50 or E51-83 in question was not a branded product. State 

laws and the markets have changed. At present jobbers can do their own blending. Thus the rules 

dealing with presumptive liability no longer make little sense since refiners no longer control the 

actions of many jobbers. 

25 Herzog, J. (January 2012). Possible Approach to Fuel Quality Standards for Fuels Used in FlexibleFuel Automotive Spark-Ignition Vehicles (FFVs), Memorandum to the docket. The memorandum is 

referenced in footnote 388 of the pre-publication proposed rule; however, the footnote reference is to a 

memorandum dated January 2012 but the memorandum in the docket is dated April 8, 2013. Further, this 

memorandum was not in the docket at the time the proposed rules were announced on EPA’s website.

Commenter: Mid-Continental Energy (MCE)

EPA is proposing the definition of any fuel that has less than 50% ethanol content be classified 

as gasoline. MCE supports that definition. For clarification in this document, any ethanol fuel 

that contains more than 51% ethanol content will be referred to as a Flex Fuel. 

In addition, EPA is proposing Flex Fuel have a sulfur content not to exceed the gasoline sulfur 

mandate. MCE agrees with EPA in their proposal. 

MCE supports the EPA premise of using RVP models to calculate and certify the final RVP of 

Flex Fuel produced from butane, natural gasoline, and denatured fuel ethanol (“DFE”) 

blendstocks which meet EPA specifications. 
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EPA is proposing allowing natural gasoline and butane as blendstocks used to produce E51 to 

E83 Flex Fuel. Our understanding is that natural gasoline specification standards will be defined 

by the EPA as butane was defined in Federal Register Title 40 Part §80.82. MCE requests that 

EPA specification standards for natural gasoline should: 1) be reasonably consistent with current 

industry specifications and standards, 2) not limit origin of the natural gasoline so long as 

specifications are met, 3) be mindful of final, blended Flex Fuel properties including vapor 

pressure, octane, benzene, and sulfur. MCE will comment on specific natural gasoline 

specifications within 90 days of this letter. MCE is conducting studies on natural gasoline quality 

and blending, and MCE can provide the study findings to the EPA on a confidential basis. 

MCE requests that a blender of natural gasoline to produce Flex Fuel would be allowed to blend 

approved butane into the natural gasoline (blendstock) before the natural gasoline is blended 

with DFE to meet the seasonal RVP requirements as allowed in EPA specifications for Flex 

Fuel. The blender will use an RVP Model approved by EPA to calculate the finished RVP of the 

Flex Fuel instead of having to test each batch of Flex Fuel leaving the terminal facility. The 

terminal blender would not have to recertify the blendstock provided the two components met all 

specifications approved by EPA before blending the two components together. 

MCE requests the EPA provide clarification on how Flex Fuel can be produced and blended. Can 

DFE producers blend Flex Fuel with existing ethanol and denaturant infrastructure? If a DFE 

producer blended approved blendstock with DFE to produce a Flex Fuel and then shipped the 

Flex Fuel to a petroleum terminal, would the terminal blender be allowed to blend butane into 

the Flex Fuel to increase the RVP to the maximum allowable RVP specifications per EPA 

seasonal specifications for Flex Fuel before the Flex Fuel is loaded into a transport truck? Could 

a petroleum terminal use Flex Fuel to blend E10-15 gasoline at the terminal in place of DFE? 

MCE would favor allowing the terminal blender to use a process analyzer to determine the RVP 

of the Flex Fuel stream in the process of blending butane into the Flex Fuel to increase the RVP 

to the maximum allowable for the seasonal variations. This is the same process presently being 

used by terminal blenders to blend butane into gasoline under the guidance in the Federal 

Register Title 40 Part §80.82. 

During the VOC period, MCE requests the EPA consider allowing blenders to blend butane and 

natural gasoline with DFE to produce Flex Fuel in RFG markets as long as the maximum RVP of 

the Flex Fuel does not exceed maximum RVP specifications as calculated by EPA approved 

RVP models. During the non-VOC season, the maximum RVP during would be under States 

rulemaking for Flex Fuel specifications. 

Under the present definition of a ‘batch’ in Federal Register Title 40 Part §80.82, EPA looks at 

each transport truck load leaving a petroleum terminal with gasoline for a service station as a 

‘batch’. EPA is proposing to allow a terminal blender to blend natural gasoline with DFE to 

produce Flex Fuel during the VOC period using an approved EPA model to calculate the 

finished blend RVP. This is a change to what is allowed under Part §80.82 for a butane blender. 

To make the rules like-minded, MCE is proposing EPA remove the language in §80.82(e)(1) 

which states ‘When butane is blended with conventional gasoline under this section during the 

period May 1 through September 15, the refiner shall demonstrate through sampling and testing, 
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using the test method for Reid vapor pressure in § 80.46, that each batch of conventional 

gasoline blended with butane meets the volatility standards specified in § 80.27.’

The terminal blender can use the model provided by EPA to calculate the RVP of the blended 

gasoline, install a downstream process analyzer to use as an oversight reporting analyzer for 

determining the RVP of the blended gasoline. RVP process analyzers on the market today take 

five to six minutes to produce results and there are several manufacturers of process RVP 

analyzers making downstream RVP a demonstrable option. MCE is not requesting to make the 

allowance applicable to gasoline marketed in RFG areas. 

MCE suggests the EPA consider new definitions for NGL, natural gasoline liquids, and/or 

pentanes. The proposed wording is potentially confusing and may not be consistent with industry 

standards. The proposed regulation defines NGL as: “the components of natural gas (primarily 

propane, butane, pentane, hexane, and heptane) that are separated from the gas state in the form 

of liquids in a natural gas production facility, in a gas processing plant, or in a natural gas 

pipeline. NGL is sometimes also referred to as “natural gasoline”.

Natural gasoline is a product of the NGL fractionation process consisting primarily of pentane 

and heavier components. MCE believes the EPA’s intends to allow Flex Fuel production using 

natural gasoline and not NGL as technically defined in the proposed regulations. 

Commenter: National Corn Growers Association (NCGA)

EPA divided its proposal for in-use fuels for FFVs into two levels by ethanol concentration: E51-

83 and E16-50 (or MLEBs). 

For E51-83, EPA proposed that these blends meet the same sulfur, vapor pressure, and benzene 

standards otherwise applicable to gasoline as well as the Clean Air Act “substantially similar” 

requirements. EPA expressed the belief that establishing such requirements could allow the use 

of butane and natural gasoline liquids to manufacture E51-83 with sufficient volatility to meet 

the ASTM specifications. We support specifications that are consistent with ASTM D5798-13, 

and allowing the use of blendstocks such as NGL, butane and others that would permit 

compliance with ASTM D5798-13. 

For E16-E50, EPA proposed that these blends meet the same standards that apply to gasoline. 

EPA also requested comments on “...whether it might be an appropriate reading of our regulatory 

and statutory authority to allow E16 to E50 blends to have higher RVP levels than otherwise 

required by our regulations for gasoline.” EPA went on to say: “As the ethanol level increases 

the volatility increase caused by blending ethanol with gasoline begins to decline, such that at 

E30 there is only about a 0.5 psi vapor pressure increase. While still an increase compared to the 

standards that apply to gasoline other than E9-E10, it is considerably less than the full 1 psi 

vapor pressure increase that results at E10. The evaporative emission increase caused by E30 

would be then be less than that for E10.” 

NCGA believes that EPA should use its regulatory and statutory authority to allow E16-50 

blends to have higher vapor pressures, so that gasoline blendstocks used currently for E10 could 
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also be used for E16-E50, and these MLEBs could be used in current FFVs. This is critical to the 

success of high octane MLEBs, since it would facilitate distribution of a high octane MLEB that 

could likely be requested by automakers to meet the 2017 and later GHG and CAFE standards. 

At least two major automakers have reported research programs evaluating advanced technology 

gasoline direct engines with high octane MLEBs (18, 19). 

18 - McCarthy, T “Fuel Octane and Ethanol Impacts on Petroleum Displacement, CO2, and the 

Consumer, Ford Motor Company, presentation at SAE High Octane Fuel Symposium, January 29, 2013.

19 - Woebkenberg, W, “Advanced Powertrain Technology Coupled with Octane and Ethanol, Benefits 

and Opportunities”, SAE High Octane Fuels Symposium, January 29, 2103.

Commenter: New York State Department of Environmental Conservation

The proposed limits on the sulfur content of blending streams such as denatured fuel ethanol are 

necessary to ensure that the program benefits are actually realized. 

Due to ethanol blending and an increase in trade of intermediate gasoline blending components 

over the last several decades, the blending of finished gasoline is no longer limited to crude oil 

refineries. In general these blenders have become refiners in the regulatory sense, with all the 

compliance documentation that entails. EPA has made efforts to allow some downstream 

blending activities, particularly ethanol blending, to be accomplished with a reduced level of 

documentation. 

The Department supports this reduced level of documentation for downstream blending, 

provided that the environmental benefits promised by Tier 3 are not compromised. This requires 

that the materials blended be sufficiently controlled to ensure that the finished gasoline will 

comply with applicable regulations. These streams must, as EPA proposes, comply with a 10 

ppm sulfur cap on their own. We believe that other properties, particularly benzene and olefins 

content, may also need to be capped to prevent backsliding. 

...and only RFG compliant gasoline or blendstock for oxygenate blending (BOB) may be used to 

produce ‘E51-83’ for use in RFG areas. This latter requirement makes it difficult to produce fuel 

that has both high ethanol content and meets the minimum ASTM volatility requirements. 

It is also necessary to regulate commercial E51-83 to ensure that emissions controls are effective 

in the field. 

The EPA staff memo discusses two possible approaches. in one approach the blender of the fuel 

is treated as a refiner, with substantial compliance documentation requirements in exchange for 

production freedom. The other approach, closer to what is done today for ethanol blending into 

BOBs to produce finished gasoline, reduces the compliance burden but limits blenders to 

blendstocks with known and regulated composition. 

Clearly the ‘ethanol blender’ approach has advantages for all concerned as long as environmental 

and fitness-for-use requirements can be reliably met. Properties such as sulfur content, benzene 
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content, aromatics content, and olefins content can be controlled by ensuring that all allowable 

blendstocks meet standards that ensure the final product will meet its standards. 

If high volatility blendstocks such as butane and natural gasoline are used as blendstocks it 

becomes possible to produce fuel that exceeds gasoline DVPE limits. EPA appears to be 

searching for a mechanism to allow this without any need to sample the resulting product and 

conduct laboratory tests. We believe that sampling and testing for DVPE can’t be avoided, 

although it may not be necessary to obtain sample results prior to releasing each truck load of 

product. Assuming that blending occurs during delivery truck loading, it may be sufficient to 

prepare and test a hand blend of the components to be used, and periodically sample truck 

compartments as part of a documented quality control program to ensure that the planned blend 

is being achieved in practice (without holding the truck for the test results). 

Commenter: Phillips 66 Company

- E51-83 – The memorandum included in the docket should not suffice as a proposed rule. We 

have reviewed the concept and have some comments. 

EPA included a memorandum in the rulemaking docket entitled “Possible Approach to Fuel 

Quality Standard for Fuel Used in Flexible-Fuel Automotive Spark-Ignition Vehicles (FFVs)”. 

We take this to be informational concerning work EPA has done to evaluate potential regulatory 

changes to provide specifications and guidance for these fuels. We do not believe this constitutes 

a proposed rule even though EPA has included draft regulatory language. In order for this to 

constitute a NPRM, the proposed language and preamble would need to be published in the 

Federal Register. 

We offer the following comments on some of the concepts that EPA discusses in the memo:

- Fuel name should be consistent on product transfer documents and labels EPA has coined the 

term E51-83 to describe what historically has been referred to as E85. While we agree that E85 is 

now an outdated term given the recent changes in the ASTM specification, there may be other 

options for naming convention of this fuel. EPA included in its conceptual PTD language a 

requirement to put a statement identifying the fuel as E51-83. Any name or reference on the 

PTDs should align with potential label nomenclature. The industry is still wrestling with what to 

call this fuel now that ASTM has modified its specification. However, consumers could be 

confused by a label that calls the fuel E51-83. We would suggest there are other options such as 

Flex Fuel (typically what is now shown on new vehicles and their gas caps) or Ethanol Fuel or 

Ethanol Flex Fuel. We suggest EPA not rush to create a designation for this fuel and require it on 

a PTD that may not be in alignment with pump labels. 

- Agree that Flex Fuel (E51-83) should be required to meet the same sulfur, benzene and 

maximum RVP standards as gasoline 

- The suggested 0.20 benzene cap for E51-83 is problematic 

Some hydrocarbon blendstocks that could be used to produce flex fuel (such as natural gasoline) 

could result in a benzene content greater than 0.20. We feel that the E51-83 should meet the 

same standards as gasoline. 

- Providing two options for sampling, testing, and reporting is a good approach 
Chapter 5: Tier 3 Fuel Sulfur Program

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Commenter: POET, LLC

Also, mid-level ethanol blends that contain 16-50% ethanol (MLEBs) are slated to be an 

important ‘fuel of the future.’ MLEBs have been assessed by auto manufacturers as providing a 

‘sweet spot’ in terms of a cost-effective fuel that can provide octane benefits (enabling greater 

engine efficiency) and lower overall vehicle emissions. 

Additionally, EPA must not burden the ethanol industry with additional, unnecessary production 

restrictions. 

The Proposed Rule takes comment on ‘whether it might be an appropriate reading of our 

regulatory and statutory authority to allow E16 to E50 blends to have higher RVP levels than 

otherwise required by our regulations for gasoline.’ (42) POET suggests that doing so is not only 

appropriate, but essential (with this regulatory relief including blends of E11 and higher). 

This RVP issue can be handled for ethanol blends of E16 and higher by, as described later in 

section 4 of these comments, by creating a separate ‘Ethanol Fuel Family’ for all blends of E16 

and higher (e.g., E16-E85). The RVP provisions in CAA Section 211(h) by their terms only 

apply to ‘gasoline,’ and thus should not apply to a blend in the ‘ethanol’ fuel family. (43) 

EPA must ensure that the various clean-burning attributes of ethanol are not prevented from 

entering into commerce by arbitrary RVP limits when in fact these MLEB and higher-level 

ethanol blends have a lower (environmentally-preferable) RVP. EPA states that it has an ability 

to broadly craft RVP standards for the ethanol fuel family per CAA Section 211(c). (44) If EPA 

can meet the statutory criteria under 211(c) for regulating RVP from higher-level ethanol blends 

(i.e., if such regulations are necessary, taking into account the inherently lower RVP of ethanol), 

this regulatory authority should be pursued to allow the equivalent of the 1 psi waiver for blends 

of E16 and above, including all MLEBs. 

E16-E85 should be regulated as a single, alternative ‘ethanol’ fuel family that covers MLEBs 

and HLEBs. In the Proposed Rule, EPA requests comment on how to regulate and promote 

MLEBs and ‘aspects of today’s proposed standards that might need to be modified to provide an 

incentive for, or remove obstacles to, the development of highly efficient vehicles optimized for 

use on higher level ethanol blends.’ (50) 

EPA further asks ‘should the Agency simply treat E16-50 as gasoline under our regulations’ or 

‘Alternatively, should the Agency treat E16-50 as an alternative fuel’? (51) Similarly, the ‘FQS 

for FFVs Memo’ in the docket raises the possibility of regulating E16-E85 vehicles as a single 

alternative fuel family. (52) POET supports this approach. This ‘fuel family’ would include both 

MLEBs and HLEBs. Importantly, an ethanol fuel family provides a means to appropriately 

structure RVP limits for MLEBs. 

Under EPA regulations, a ‘fuel family’ is defined as ‘a set of fuels and fuel additives which share 

basic chemical and physical formulation characteristics and can be used in the same engine or 

vehicle.’ (53) Given that ethanol blends from E16 through E85 today ‘can be used in the same 

engine or vehicle’ (i.e., an FFV), it is more appropriate that MLEBs be regulated within the 
Tier 3 Summary and Analysis of Comments

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existing ethanol fuel family (which includes HLEBs), as opposed to being considered gasoline. 

(54) By comparison, MLEBs cannot be used in an ordinary ‘gasoline’ vehicle. 

An E16-E85 ‘Ethanol Fuel Family’ can readily meet core fuel quality standards, including 

appropriate chemical composition, benzene, and sulfur; a separate fuel family also provides a 

means to appropriately structure RVP limits for MLEBs. 

EPA believes that it is important that fuel quality requirements for chemical composition, sulfur 

and benzene ‘apply to any fuel used in an FFV.’ (55) Regarding chemical composition, EPA 

believes that it is appropriate to explicitly apply to ethanol blends ‘substantially similar’

requirements that ‘E51-83 must be composed solely of carbon, hydrogen, nitrogen, oxygen, and 

sulfur.’ (56) POET supports ‘substantially similar’ chemical composition requirements, and they 

can be readily applied across a single Ethanol Fuel Family comprised of E16-E85 blends. (57) 

Similarly, sulfur and benzene limits must be properly structured, but should not be a problem for 

E16-E85 blends, given that ethanol contains no benzene and is nearly sulfur-free. (58) 

Finally, as discussed above in Section 3 of these comments, it is absolutely imperative that EPA 

address unnecessary and environmentally counter-productive RVP limits that prohibit the use of 

MLEBs. An Ethanol Fuel Family provides a ready means to have MLEBs subject to an 

appropriately designed RVP limit that is different than that for ‘gasoline’ but nonetheless 

adequately protective. (59) HLEBs could be subject to this standard as well, although an 

alternative RVP standard is less critical for HLEBs because ethanol blends greater than 50% can

already meet existing ‘standard’ RVP limits, due to the inherently environmentally-friendly RVP 

of unblended ethanol. (60) 

Benzene limits for ethanol blends must take into account the gasoline blended with ethanol. 

EPA believes ‘it may be possible to set the benzene standard for E51-83 at a 0.20 volume percent 

cap or even lower without imposing any burden rather than implementing an average annual 

benzene standard similar to that for gasoline.’ (77) Gasoline has a 0.62 volume % average 

maximum benzene content. 

A benzene cap of 0.20% on ethanol blends would create a tremendous burden on blenders and 

could render certain production impossible. For instance, an E51 blend composed of 51% DFE 

and 49% certified gasoline would likely have a benzene content of 0.31% as the gasoline would 

bring 0.62% benzene to the mixture. This mixture would not meet the regulatory requirements. 

Under the proposed approach, E51-83 could only exist as E75-83 with DFE at a 0.06% benzene 

and gasoline at 0.62% benzene. Higher benzene levels in the gasoline due to averaging would 

further limit the hydrocarbon content of this fuel as well as the RVP and cold start capability in 

cold weather. It is imperative that EPA provide a higher benzene limit to account for the gasoline 

blended with ethanol. POET believes EPA should set this benzene standard at 0.62 volume %, 

identical to the gasoline limit and the directly competitive fuel. 
Chapter 5: Tier 3 Fuel Sulfur Program

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EPA’s streamlined ‘Blender Option’ requirements should be the default regulations for E16-E85 

production (as opposed to full refiner responsibilities). 

The Tier 3 rulemaking appropriately recognizes that ethanol blending is of central importance to 

our nation’s transportation fuel supply and accomplishing key environmental and energy security 

goals. To achieve these goals and maintain a robust domestic transportation fuel supply, it is 

critical that EPA design its regulations to facilitate the production and blending of ethanol. 

EPA discusses its possible approaches to the regulation of ethanol (and vehicles that use ethanol) 

in the Proposed Rule, including the section ‘Standards for Fuel Used in Flexible Fueled 

Vehicles.’ (78) This section then references a detailed memo to the docket, the FQS for FFVs 

Memo. 

The FQS for FFVs Memo outlines two options for regulating manufacturers of E51-E83. POET 

strongly supports ‘Option 2: Treatment as a Blender’ (the ‘Blender Option’) as the default 

option. Under this Blender Option, EPA states that E51-E83 producers can reduce their 

regulatory burden if they only use blendstocks that meet certain specifications that would ensure 

sulfur and benzene do not exceed appropriate amounts. (79) 

More specifically, under this Blender Option, EPA proposes generally to limit blendstocks for 

ethanol blends to gasoline, BOBs, and DFE, as well as natural gas liquids (NGLs) and butane if 

they are produced to certain standards. Under this Blender Option, the finished E51-83 would be 

subject to the proposed downstream sulfur cap for gasoline of either 65 ppm or 95 ppm. (80) A 

benzene limit would also apply to the finished blend (discussed above). 

POET agrees that testing of final blends would not be needed as the DFE and blendstocks are 

regulated individually for sulfur and benzene (and RVP issues can be handled in a streamlined 

fashion as well). 

POET also believes that the less-stringent Blender Option requirements could apply equally to 

E16-E50 as well as E51-E83. The FQS for FFVs Memo also notes that ‘the draft regulations 

written to address E51-83 might be modified to cover E16-50 blends.’ (81) POET believes that 

this Blender Option can be applied across an Ethanol Fuel Family from E16-E85 (i.e., across 

both MLEBs and HLEBs). If EPA considers it necessary to further delineate MLEB blending, 

POET suggests that applicable ASTM standards already provide a suitable approach. In 

particular, ASTM Standard D7794 allows MLEBs only to be created from a mixture of gasoline 

and DFE, or gasoline and HLEBs. (82) Thus, the constituents of MLEBs (gasoline, DFE, and 

HLEBs) are already controlled. This is consistent with the streamlined ‘Blender Option’ that 

avoids batch testing for blends when the constituents of those blends are already controlled. 

While POET supports EPA’s Blender Option approach, blendstocks for ethanol blends (i.e., 

those substances blended with DFE to achieve a certain ethanol/’gasoline’ blend) should not be 

regulated more than is necessary to accomplish EPA’s emission-control goals, as further 

discussed immediately below. 
Tier 3 Summary and Analysis of Comments

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Under the Blender Option, gasoline blendstocks should be allowed for blending (in addition to 

NGLs and butane) as long as they meet adequate specifications. 

Light straight run naphtha, hydrotreated naphthas, and hydrotreated natural gasoline are potential 

streams to consider. These gasoline blendstocks could be subject to the same sulfur and benzene 

specifications as NGLs and butane and should be allowed as blendstocks for ethanol blends. 

POET agrees with EPA that addressing RVP in blends does not require batch testing. 

EPA states that ‘For blenders that use only gasoline, BOB’s, and DFE to produce E51-83, 

demonstration of compliance with the maximum RVP standard under consideration could be 

accomplished by retention of PTDs [Product Transfer Documents] for the blendstocks.’ (83) 

Additionally, EPA raises the issue of whether the SAE ‘Model for Estimating Vapor Pressures of 

Commingled Ethanol Fuels’ is adequate to avoid testing for NGLs and refinery naphthas for 

RVP. (84) POET agrees that the SAE model referenced in the FQS for FFVs memo should be 

adequate to avoid testing for NGLs and refinery naphthas for RVP. (85) 

EPA states that ‘Given the proposal in the Tier 3 NPRM to limit the denaturants that can be used 

to manufacture DFE to NGL, gasoline, and BOBs, and the narrow range in denaturant 

concentration, we believe that the RVP of different batches DFE would not vary substantially. 

Therefore, we currently do not believe that deliveries of new batches of DFE into the storage 

tank used to produce E51-83 would necessitate a return to per batch testing.’ (86) POET agrees 

that the variability of the ethanol RVP would not vary substantially, and batch testing should not 

be required, with a 5% denaturant cap. 

POET supports facilitating the use of NGLs under the Blender Option in the production of 

ethanol blends. 

POET does not believe that any EPA limits on the volume of NGL used as a blendstock are 

necessary for HLEBs (E51-E83). For MLEBs (E16-E50), if EPA considers that some NGL 

limits are necessary, POET suggests that applicable ASTM standards already effectively limit 

the NGL content in MLEBs. In particular, as noted above, ASTM Standard D7794 allows 

MLEBs only to be created from a mixture of gasoline and DFE, or gasoline and HLEBs. The 

amount of NGLs allowed in these constituent products (gasoline, DFE, and HLEBs) is already 

controlled. Therefore, the volume of NGL in MLEBs can effectively be no greater than what is 

already contained in approved components of an MLEB. 

Furthermore, POET responds to the following statements by EPA regarding NGLs under the 

Blender Option:

- Production ‘using NGL blendstocks would require that the NGL blendstock, like butane, meet a 

10-ppm per-gallon sulfur cap.’ (87) 

- POET agrees that NGL (or gasoline blendstocks such as hydrotreated refinery streams) used for 

blending E16-E83 should meet the proposed 10 ppm sulfur cap under the Blender Option and 

therefore avoid burdensome batch testing requirements for blending. 
Chapter 5: Tier 3 Fuel Sulfur Program

5-158

- EPA notes that ‘Similar to the envisioned 0.20 volume percent benzene cap for butane, we 

would look to implement a 0.20 volume percent benzene cap standard for NGL rather than an 

average standard in order to simplify the regulatory requirements.’ (88) 

- A benzene cap of 0.20% for NGLs is too restrictive and may be impractical to meet. The 

benzene standard for NGLs should be 0.62% benzene similar to unleaded gasoline. Therefore, 

this NGL stream or gasoline could be used in the blend with no detrimental effect to the finished 

fuel since the DFE in which it is blended will have little to no benzene. 

- ‘Since NGL properties from different sources can vary widely ... we may also need to consider 

restricting the sources of NGL to natural gas liquids fractionation facilities and natural gas 

processing plants to ensure an appropriate level of quality control.’ (89) 

- EPA should maintain a provision for an alternative NGL source to allow for hydrotreated 

streams or refinery streams that meet the same criteria (i.e., benzene and sulfur limits). Refineries 

(including facilities where hydrotreating takes place) can provide the same or superior quality 

control as NGL fractionation facilities and natural gas processing plants. 

- ‘Stakeholders have stated that as additive concentration diminishes due to dilution with DFE, 

there is a point where the presence of a deposit control additive ceases to be beneficial and can 

actually contribute to deposit formation. In light of this, it may be appropriate to remove the 

requirement that the gasoline portion of E51-83 and perhaps E16-50 must contain a deposit 

control additive until the specific deposit control needs of these blends can be evaluated.’ (90) 

- POET supports removing the requirement that the gasoline portion of E51-E83 must contain a 

deposit control additive until the specific deposit control needs of these blends scan be evaluated. 

A similar approach may be warranted for E16-E50. 

EPA should not unduly regulate E16-E83 blendstocks. EPA states that ‘Currently, only ... 

RBOBs ... and gasoline ... are used to manufacture E51-83.’ (91) This is inaccurate. Gasoline 

blendstocks and natural gasoline can also be used in E51-E85 today. (92) 

Some ethanol producers may wish to use non-standard blendstocks, which they should maintain 

the option to do as long as the end product meets appropriate specifications. Ethanol producers 

should have the option to do so, if they opt to undertake broader ‘refiner’ responsibilities. These 

‘refiner’ responsibilities could require batch testing of the end product, and some ethanol 

producers may consider this extra cost and burden appropriate. (93) 

The proposed definition of NGLs in 40 CFR 80.2 is too restrictive. (97) The definition should 

not include an unduly narrow listing of the types of facilities that produce NGLs and should 

include, for instance, NGLs that may be produced through refineries and hydro-treating. The 

definition should be revised as follows (with additions underlined): ‘(zzz) Natural Gas Liquids 

(NGL) means the components of natural gas (primarily propane, butane, pentane, hexane, and 

heptane) that are separated from the gas state in the form of liquids in facilities such as a natural 

gas liquids fractionation production facility, or in a natural gas processing plant, or in a natural 

gas pipeline, or refinery or similar facility. The higher temperature boiling components of NGL 

are sometimes also referred to as ‘natural gasoline’.’ 

A requirement to ‘Certify that the NGL was derived solely of from [sic] natural gas liquids 

fractionation facilities and natural gas processing plants’ is too narrow. (98) As noted above, 
Tier 3 Summary and Analysis of Comments

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EPA should include refineries (including hydrotreating) as potential hydrocarbon stream sources 

as long as blendstocks meet certain requirements (i.e., benzene and sulfur limits).

A requirement to demonstrate ‘that the benzene content of each production batch of NGL is not 

greater than 0.03 volume percent’ is too restrictive. (99) This specification is unrealistic, and it is 

unclear whether a product that meets this specification even exists in any significant commercial 

quantities. For instance, this specification is 20 times more stringent than gasoline and wouldn’t 

apply to NGLs blended directly into unleaded gasoline. 

A prohibition that ‘NGL and E51-83 made from NGL cannot be sold as gasoline or E16 or be 

commingled with gasoline or E16-50 and subsequently sold as gasoline or E16-50’ is unduly 

restrictive. (100) This prohibition on commingling E51-83 made with NGL with MLEBs would 

unduly limit the ability for retail stations to provide E16-E83 fuels, especially if they employ 

blender pumps. Alternatively, EPA should be guided by ASTM requirements as stated in 

standards D4814, D4806, D5798 and standard practice D7794. 

51. - Id. at 29,938.

52 - See FQS for FFV Memo, supra, at 10 (stating that, instead of regulating MLEBs as ‘gasoline,’ EPA 

‘could treat E16-50 as an alternative fuel used in FFVs.’).

53 - See 40 CFR 79.50 (emphasis added). EPA has designated six fuel families per 40 CFR 79.56, 

including gasoline, diesel, methanol, ethanol, methane, and propane.

54 - In any possible re-categorization of MLEBs, EPA should ensure that no testing burdens are 

increased, and that all other applicable regulations are appropriate for ethanol blends.

55 - 78 Fed. Reg. at 29,937.

56 - FQS for FFVs Memo, at 6.

57 - However, these ‘substantially similar’ requirements for ethanol should also allow the presence of 

chlorine and sulfur, per the current provisions for the ethanol fuel family at 40 CFR 79.55(e).

58 - However, gasoline that is blended with ethanol does contain benzene; appropriate benzene and sulfur 

limits for blends in the Ethanol Fuel Family are discussed in the section 5 of these comments.

59 - The ‘FQS for FFVs Memo’ recognizes that categorizing MLEBs in an ethanol fuel family would 

allow RVP regulations different from those applicable to ‘gasoline’ to apply. Id. at 11.

60 - As noted above, it is only when ethanol is blended with significant concentrations of gasoline does 

the mixture of the two substances exceed current RVP limits in certain circumstances.

77 - FQS for FFVs Memo, at 5.

78 - 78 Fed. Reg. at 29,936-38.

79 - Some ethanol producers may wish to use non-standard blendstocks, which they should maintain the 

option to do as long as the end product meets appropriate specifications. Ethanol producers should have 

the option to do so, if they opt to undertake broader ‘refiner’ responsibilities. These ‘refiner’

responsibilities could require batch testing of the end product, and some ethanol producers may consider 

this extra cost and burden appropriate.

80 - FQS for FFVs Memo, supra, at 7.

81 - Id. at 11.

82 - See ASTM D7794-12 (D7794) ‘Standard Practice for Blending Mid-Level Ethanol Fuel Blends for 

Flexible-Fuel Vehicles with Automotive Spark-Ignition Engines.’ This standard incorporates by reference 

ASTM standards governing the permissible constituents of MLEBs including one for gasoline (D4814), 

as well as ASTM D4806-12 (‘Standard Specification for Denatured Fuel Ethanol for Blending with 

Gasolines for Use as Automotive Spark-Ignition Fuel’) (DFE), and ASTM D5798-12 (‘Standard 

Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition Engines’) (HLEBs).

83 - FQS for FFVs Memo, at 7.
Chapter 5: Tier 3 Fuel Sulfur Program

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84 - By way of background, EPA stated ‘If NGL and/or butane were used to manufacture E51-83, 

demonstration of compliance with a maximum RVP requirement could not be accomplished merely by 

retention of PTDs.... However, it may be possible to avoid sampling and testing for RVP as well. RVP 

models exist that could perhaps be developed further to avoid the need for sampling and testing for RVP 

when NGL or butane were used, but they are not yet applicable to these blends.’ Id.

85 - See id. at 7 n. 22 (referencing SAE paper 2007-01-4006, ‘A Model for Estimating the Vapor 

Pressures of Commingled Ethanol Fuels.’).

86 - Id. at 8.

87 - Id. at 9.

88 - Id.

89 - Id. at 10.

90 - Id. at 11.

91 - 78 Fed. Reg. at 29,937.

92 - See, e.g., ASTM standard for H LEBs, ASTM D5798-12.

93 - Under either the Blender Option or the more stringent refiner option (which would regulate ethanol 

producers similar to gasoline refiners), the resulting E16-E83 ‘produced would be required to meet the 

downstream sulfur, RVP, and a benzene per-gallon cap standard in order to ensure emission performance 

over the life of the vehicles that use it.’ FQS for FFVs Memo, supra, at 4.

97 - See FQS for FFVs Memo, supra, at 13; also, 78 Fed. Reg. at 30,003.

98 - See FQS for FFVs Memo, at 20. ‘ Id.

100 - Id.

Commenter: Renewable Fuels Association (RFA)

Existing standards and specifications for “flex fuels” (i.e., 51-83%vol. ethanol) are sufficient and 

EPA should not subject these fuels to the same sulfur, RVP, and benzene standards applicable to 

gasoline 

RFA agrees with EPA that increased volumes of higher ethanol blends will be used in flexiblefuel vehicles (FFVs) with implementation of the expanded Renewable Fuels Standard (RFS2). 

RFA has dedicated resources to develop both the proliferation of the manufacture of FFVs and 

the retail fuel offering for “flex fuels,” ethanol blended fuels containing 51 to 85% ethanol 

(volume.) There are effective fuel quality specifications already in existence for these flex fuels; 

ASTM International publishes the fuel specification D5798-13 “Standard Specification for 

Ethanol Fuel Blends for Flexible-Fuel Spark Ignition Engines.” RFA supports the continued 

responsibility of ASTM International, of which EPA is a member of the D5798 Task Force, to 

further describe the characteristics needed for flex fuels. The ASTM D5798-13 specification 

includes regulatory restrictions and has a track record of timely and frequent content update. 

Recently, the D5798 specification has undergone significant improvements to better characterize 

and require appropriate blending components and blending practices. Where EPA regulations 

may have appeared silent on requirements for flex fuels, ASTM International has stepped in to 

address these issues with robust restrictions for flex fuels. The ASTM D5798-13 flex fuel 

specification does not allow inappropriate blending components. The ASTM standards process is 

designed for industry and government driven consensus standards with a thorough vetting 

process. RFA supports the use of NGLs, butane and other ASTM D5798-13 suitable 

hydrocarbons as the balance of the fuel blend with ethanol. EPA must avoid prescribing onerous 

and unprecedented requirements, such as a minimum and maximum vapor pressure, for flex 

fuels. RFA supports the continued reliance on ASTM D5798-13 to describe ethanol fuel blends 
Tier 3 Summary and Analysis of Comments

5-161

containing 51-83% ethanol and to allow blending of flex fuels with ASTM D5798-13 allowed 

hydrocarbons in all markets including RFG areas. 

E16-E50 blends should be treated as alternative fuels. 

RFA supports EPA’s continued treatment of E16-50 fuels as alternative fuels; this range of fuel 

blends is only legally allowed for use in FFVs. E16-50 fuel blends are not gasoline. In fact, a fuel 

blend being predominantly gasoline does not effectuate the use of that fuel blend in gasolinecertified vehicles. 

RFA agrees with EPA that data gaps exist on the effectiveness of detergents in E16-83 ethanol 

fuel blends. Currently, there is insufficient data to render a decision of the effectiveness across 

the broad range of FFVs in the marketplace. RFA continues to investigate the most efficient and 

effective composition of these fuel blends and will continue to play a role in addressing data 

gaps. 

RFA supports the EPA requirement for “substantially similar” for all fuels: gasoline and 

alternative, which restricts the composition to only carbon, hydrogen, oxygen, nitrogen and 

sulfur. 

Commenter: Shell Oil Products for Shell and Motiva

In the preamble and in a separate document entered in to the docket (April 8, 2013 memorandum 

from Jeff Herzog, “Possible Approach to Fuel Quality Standards for Fuel Used in Flexible-Fuel 

Automotive Spark-Ignition Vehicles (FFVs)”) EPA discusses potentially regulating - 83 and 

E15-50. In general, we agree that these fuels should be regulated similar to gasoline. As it is, 

these fuels are essentially exempt from the sulfur, benzene, and detergent additive requirements 

that apply to gasoline. 

The following identifies numerous specific issues in the provisions included in the Herzog 

memo, and makes recommendations to address those issues. 

Of the issues discussed below, one is particularly noteworthy. The suggested benzene level for 

E51-85 of 0.2 vol% is too low and is not consistent with the existing benzene specifications for 

gasoline. If EPA proceeds with this, it will essentially require specialized blendstocks with lower 

benzene levels to produce E51-85. 

80.2 Definitions: New paragraph 80.2(cccc), which will provide the definition for E51-83, 

includes the reference to the ASTM D5798-11 standard for ethanol fuel blends for FFV’s. This 

reference should be updated to reflect the currently published version ASTM D5798¬13 and 

should be updated further if a newer version is adopted by ASTM. 

80.1601 Fuels subject to the provisions of this Subpart: EPA proposes adding item 80.1601(a)(4) 

to explicitly include E51-83 as being subject to the provisions of Subpart O regarding gasoline 

sulfur. However, we do not see an explicit addition to also include E16-50. Assuming EPA 
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believes Subpart O regarding gasoline sulfur should also apply to E16-50, then E16-50 should 

explicitly also be listed in 80.1601(a). 

- Under, 80.1601(b)(2), “California gasoline as defined in §80.1600 subject to the provisions of 

§80.1654” is not subject to the standards and requirements of Subpart O. Do the requirements of 

Subpart O apply to E51-83 and/or E16-50 sold in California? And if so, how do they apply? 

80.1608 Standards and requirements for E51-83: Apart from the compliance dates for the new 

sulfur levels via the requirements in 80.1603(a)(2), paragraph 80.1608 does not specify an 

effective date for the standards and requirements for E51-83. EPA needs to insert a clear 

effective date for all of the standards and requirements for E51-83 in 80.1608. We infer this is 

sometime in 2017, but ask that EPA specify the effective date in the regulation. 

- 80.1608(b)(2) as proposed sets the maximum benzene content of each batch of E51¬83 at 0.20 

volume percent maximum. This benzene limit is too low, because it is inconsistent with EPA’s 

clear intent to allow E51-83 blenders to manufacture E51-83 using gasoline, gasoline 

blendstocks for oxygenate blending, denatured fuel ethanol, natural gas liquids, and/or butane 

per 80.1611. 

- As an example, per 80.1611, E51-83 can be made from compliant RFG and compliant 

denatured fuel ethanol. In this case with: 

- the benzene content of E10 RFG being up to 1.30 vol% benzene and 

- the amount of E10 RFG in the blend potentially being as much as ~53 vol% of the total fuel 

recipe (resulting in a final blend containing 51% pure ethanol), 

- the final E51-83 made using RFG may contain up to ~0.69 vol% benzene. However, this would 

conflict with EPA’s proposed 0.20 vol% benzene limit for E51-83. The benzene content of the 

E51-83 may be even higher when conventional gasoline is used in the E51-83 recipe instead of 

RFG (or RBOB). EPA needs to eliminate the explicit benzene limit in E51-83 when a blender 

manufactures this fuel under the provisions of 80.1611. Otherwise, EPA needs to increase the 

explicit benzene limit to reflect EPA’s intent to allow E85 production using compliant RFG, 

RBOB, CG, and/or CBOB. 

- Section 80.1608(b)(4) listing the RVP requirements for E51-83 contains the typographical error 

“80.1627(a)(2)” when “80.27(a)(2) is intended by EPA. The EPA intended language should be: 

“The Reid vapor pressure of each batch of E51-83 must comply with the same standards 

applicable for gasoline in §80.1627(a)(2). 

- EPA should clarify that section 80.1608(b)(4), which would require that “each batch” of E51-

83 must comply with same standards applicable for gasoline in 80.27(a)(2), only applies to E51-

83 blenders (and refiners, importers, distributors, resellers, and carriers). If EPA also intends for 

the RVP requirements to be applicable during the “high ozone season” from June 1st through 

September 15th of each year at retail sites as well, then EPA has to recognize and address the 
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potentially far slower turnover of E51-83 inventory at retail sites (relative to gasoline) may make 

an RVP requirement at retail sites infeasible and dissuade retailers from offering E51-83. EPA 

should note that ASTM recognized and addressed this issue of potentially slow moving E51-83 

at retail sites by exempting the E51-83 at a retail site from ASTM’s seasonal RVP requirements 

in ASTM’s “E51-83” standard D5798 Table 2 with note1 as follows (emphasis added), “This 

schedule, subject to agreement between the purchaser and the seller, denotes the vapor pressure 

class of the fuel at the time and place of bulk delivery to fuel-dispensing facilities for the end 

user. Shipments should anticipate this schedule.” 

- 80.1608(c)(3) provides the benzene standard for E51-83 when it is manufactured by a party that 

does not qualify as an E51-83 blender: 

- Similar to our comments regarding the 0.20 vol% benzene limit for E51-83 blenders in 

80.1608(b)(2) being too low. 0.20 vol% benzene listed in 80.1608(c)(3) for E51-83 “refiners” is 

also too low and should be revised consistent with our recommendations for E51-83 blenders. 

- We believe “80.1632” is a typographical error with regard to the test requirements for benzene 

in E51-83 produced by a “refiner”. We believe EPA means and should correct this to “80.1630” 

which deals with test requirements. At this time no section 80.1632 appears proposed or intended 

by EPA. 

80.1611 Blended E51-83 requirements: 

- EPA needs to insert a clear effective date for the blended E51-83 requirements in 80.1611. We 

infer this is sometime in 2017, but request that EPA specify the effective date. 

- As proposed by EPA, 80.1611(a) and (b) require that only RFG or RBOB be used as the 

gasoline or gasoline blendstock for oxygenate blending in E51-83 intended for sale in RFG 

areas. EPA has not provided a basis for this limitation based on air quality impact. Absent EPA 

providing a reasonable basis, these requirement should be deleted from EPA’s proposed rules, 

allowing conventional gasoline and/or CBOB to be used as well for E51-83 in RFG areas. 

80.1612 Standards and requirements for natural gas liquids blendstock used by E51¬83 blenders:

- 80.1612(b) as proposed includes a prohibition on using E51-83 made from NGL in a blend with 

gasoline to make E16-50. We do not understand EPA’s logic in this prohibition and ask that EPA 

explain its reasoning further. 

80.1662 Liability for violations under Subpart 0: 

- For a sulfur cap standard violation in 80.1660(b), paragraph 80.1662(a)(5) includes a branded 

refiner/importer liability as follows (emphasis added): 

“ Branded refiner/importer liability. Any refiner or importer whose corporate, trade, or brand 

name, or whose marketing subsidiary’s corporate, trade, or brand name appeared at a facility

where a violation of §80.1660(b) occurred, is deemed in violation of §80.1660(b).” 

However, this branded refiner/importer liability is too broad when EPA is now proposing to 

further expanded the sulfur cap requirements in 80.1660(b) to include E16-50 and E51-83 fuels 

sold at retail sites where the branded refinery has no control on the retailer who might 

independently make these product offerings from sources of his/her own choosing. Branded 

refiners should not be liable in these cases simply because their brand name “appeared at a 
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facility”, especially in the case where the branded refiner contractually required the retailer to 

identify at the dispenser that the E16-50 or E51-83 in question was not a branded product. 

The Herzog memo discusses detergent additives for E51-85. EPA is seeking comment on the 

amount (if any) of detergent additive needed. 

The EPA proposed regulation for E85 (51% to 83% pure ethanol) and Mid-Level Ethanol blends 

(16% to 50% pure ethanol), for use only in Flex Fuel Vehicles states: 

“Stakeholders have stated that as additive concentration diminishes due to dilution with DFE, 

there is a point where the presence of a deposit control additive ceases to be beneficial and can 

actually contribute to deposit formation. In light of this, it may be appropriate to remove the 

requirement that the gasoline portion of E51-83 and perhaps E16-50 must contain a deposit 

control additive until the specific deposit control needs of these blends can be evaluated”. 

There is evidence that unadditized E85 generates deposits on inlet valves. There is also evidence 

that the use of additives in E85 helps to remove inlet valve deposits. Therefore, we recommend 

that EPA maintain the approach taken in the current deposit control regulations which require 

that the gasoline portion of E51-83 and E16-50 must contain a certified deposit control additive 

at a concentration at least as great as that used during gasoline deposit control additive 

certification testing (referred to as the Lowest Additive Concentration or LAC). If EPA should 

decide to pursue changes to the current approach, we recommend that EPA initiate a stakeholder 

process to vet the issues. 

Commenter: Sunoco Logistics Partners L.P.

As the owner/operator of approximately 40 refined product terminals, nearly all of which, 

inventory and blend ethanol, Sunoco Logistics supports expanding the use of blend stocks like 

butane and natural gasoline to manufacture E51-83, provided the finished E51-83 blend meets 

existing industry standard ASTM 5798. At the lower fuel ethanol ranges (i.e., E51), the use of 

butane and natural gasoline as blend stocks would likely require the addition of other lower 

volatility components to meet all volatility standards in ASTM 5798. 

To meet the envisioned flex fuel quality standards and comply with the applicable sections of the 

CAA, we support providing maximum flexibility by allowing E51-83 producers to choose 

between option 1 (refiner) or option 2 (blender) as outlined in the 4/8/13 memorandum authored 

by Jeff Herzog. The option 2 approach requiring blend stock specifications, quality control 

testing and reporting should parallel the requirements under 40CFR80 for blending butane into 

conventional gasoline. 

Our Response:

As explained in Section V.H. of the preamble to today’s final rule, we are deferring final 

action not on these provisions at this time. We appreciate the valuable input provided by the 

commenters and will take this into consideration in our final actions on these standards. We will 

continue to work with stakeholders in developing in-use fuel quality standards for higher level 
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ethanol blends. We may issue a supplementary proposal prior to issuing a final rule if the 

additional information we receive from stakeholders warrants such an action.

5.5. Flexibilities

5.5.1 General

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

The main concern with the protracted compliance flexibility in the proposed rule is that it 

enables on-going unpredictable and unidentified “hot spot“ issues where chronically high sulfur 

fuels may be sold, forcing OEMs to manufacture vehicles that can perform at higher sulfur level 

to account for such variability. The flexibility also generally precludes uniformity at the retail 

pump and therefore makes it more difficult to achieve emissions reductions across the country. 

The Alliance and Global Automaker support a reasonable date for 100% compliance with sulfur 

standards, and urges EPA to further limit the period for early crediting and trading that will delay 

full compliance with the rule. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

The so-called flexibilities proposed in the rule do little to offset the burden of compliance.

Commenter: Manufacturers of Emission Controls Association (MECA)

MECA also appreciates the importance of providing some compliance flexibilities to the oil and 

refining industries (as EPA has done in past fuel sulfur regulations) to facilitate cost-effective 

compliance with the standards. 

Commenter: Michigan Department of Environmental Quality (MDEQ)

The USEPA is proposing to use phase-in flexibilities, credit and allowance programs, more lead 

time for small business and manufacturers, and hardship provisions as has been historically done. 

The MDEQ, Air Quality Division supports this flexibility. A reduced number of United States 

refineries in recent years has resulted in temporary fuel price spikes when events take them ‘offline.’ However, pollutants emitted due to high sulfur content in fuel have a cost to the 

environment and the public’s health that can be much greater and longer duration. With the 

multitude of complex issues regarding cost to citizens, to refineries, to the environment and to 

health, these allowances for special cases seem prudent. 

Commenter: Ozone Transport Commission (OTC)
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We anticipate that EPA will ensure flexibility for automobile manufacturers and refiners of 

gasoline through averaging, banking, trading programs, or other mechanisms as appropriate 

without diminishing the environmental benefits of the rule. 

Additionally, refineries should be extended flexibility to avoid 2 turnarounds (shutdowns and 

startups for major maintenance or equipment installation) in a relatively short time period. To the 

extent reasonable, the equipment installation for low sulfur fuel equipment should be 

accommodated during a normally scheduled maintenance turnaround. This avoids the excess 

emissions that occur during multiple shutdowns and startups of a refinery. 

Commenter: Pennsylvania Department of Environmental Protection (DEP)

DEP supports flexibility for...refiners of gasoline through averaging, banking, trading programs, 

or other mechanisms and efforts to mitigate those costs by providing time to install needed 

equipment at refineries. 

Commenter: State of Utah

Utah supports including mitigation provisions in the final rule to help refineries as they transition 

to Tier 3 gasoline, including providing an averaging, banking, and trading (ABT) program to 

allow refineries to spread out the cost of these investments among their facilities and hardship 

and flexibility provisions (e.g., delayed implementation) for small volume refineries such as 

those in Utah. 

Commenter: Union of Concerned Scientists (UCS)

We also support the flexibilities in the Tier 3 standard that were also used in the Tier 2 program. 

Commenter: Utah Air Quality Board

The Board further recognizes that the low-sulfur gasoline component of the proposed Tier 3 

Program will require significant investments by Utah’s petroleum refineries. The Board supports 

EPA’s efforts to mitigate the economic impacts of the Tier 3 Gasoline on this industry, 

including, but not limited to, providing an averaging, banking, and trading (ABT) program to 

spread out the cost of these investments and proposing hardship provisions and flexibility 

provisions (e.g., delayed implementation) for small volume refineries such as those found in 

Utah. 

Our Response:

As discussed more below in Chapters 5.5.2 through 5.5.4 (and in Section V of the 

preamble to the final rule), we are in fact finalizing a number of flexibilities in the Tier 3 

gasoline sulfur program including: a nationwide ABT program, with the ability to use Tier 2 

“banked” credits; a three-year delay for approved small refiners and small refineries; and 

hardship provisions. We believe that these flexibilities address concerns of the potential for 
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having off-cycle turnarounds (which could in turn lead to supply and/or pricing issues) and will 

help to reduce the burden of compliance on regulated entities. In response to comments, we have 

also made changes to the final ABT program that we believe will allow for a smooth transition 

between the Tier 2 and Tier 3 ABT programs, and provide more certainty for refiners of the 

availability of credits—thus allowing refiners to spread out the cost of their investments among 

their facilities and in a manner that best works for them.

With regard to the concern that flexibilities preclude uniformity of the gasoline sulfur 

standards, we note that the January 1, 2020 compliance date for small refiners and small 

refineries is also the date that all refiners and importers can no longer use credits that were 

generated with respect to the 30 ppm sulfur standard. Therefore, all production and credit 

generation/use will be relative to the 10 ppm average sulfur standard at this point. As discussed 

above in Chapter 5.1.2, we do not anticipate any such “hot spot issues” that the commenter 

mentioned.

5.5.2. Averaging, Banking, and Trading (ABT) Program

5.5.2.1 General 

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

API and AFPM support the inclusion of an ABT program as part of the Tier 3 regulations that 

allows refiners (including blender refiners) and importers to generate early and standard credits. 

We generally agree with the structure of the standard credit generation program, allowing credits 

to be generated for gasoline that over-complies with the 10 ppm annual average standard. Some 

changes are needed to make the system more effective, including changes to early credit life, 

treatment of remaining Tier 2 credits, trading restrictions, and the deficit carryover provisions. 

Commenter: Chevron Products Company

If EPA proceeds with the gasoline sulfur reduction, we do support several of the proposed 

elements including: averaging, banking and trading program.

EPA’s refinery modeling assumes very optimistic refinery conversion timing and also assumes 

that refineries would target a 10 ppm level when in fact refineries would have to target a lower 

level (e.g., 8 ppm or lower) to ensure that the annual average met the 10 ppm standard. Also, the 

proposed Averaging, Banking and Trading (ABT) program is required to be widely used by the 

participants in order that the costs be kept down and to meet the proposed implementation 

timeline — this represents the ideal situation. There is uncertainty about the number of credits 

that will be available in the market to allow parties to meet the 10 ppm annual average standard. 

We believe that use of the ABT should be a ‘relief valve’ for compliance and not a critical 

component. 
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While the ABT program does provide flexibility for refiners, the short three-year implementation 

time period removes a great portion of the benefit of this flexibility by requiring refiners to use 

the ABT program to manage their investment program and stay in compliance. Refiners who 

choose to invest for compliance on time for a 2017 start may be unable to do so due to the time 

required for capital investment, permitting, and construction. Reliance on the ABT program to 

obtain credits for compliance should be an option for refiners, not a requirement. A refiner 

should have a clear path to meet the new sulfur standards by investing early and being able to 

meet the start date without having to use the ABT program. 

Commenter: Countrymark

CountryMark believes that the ABT program will provide an easier way for the refining industry 

to transition from Tier 2 fuels requirements to Tier 3 fuels requirements. This program provides 

opportunities for obligated parties to meet compliance through a sulfur credit program. 

Commenter: Small Business Refiners (SBR)

Sulfur Average, Banking, and Trading (ABT) Program: The Small Business Refiners believe that 

the ABT program will provide way for the refining industry to transition from Tier 2 fuels 

requirements to Tier 3 fuels requirements. This program provides opportunities for obligated 

parties to meet compliance through a sulfur credit program. 

Commenter: Environmental Defense Fund (EDF)

The averaging, banking, and trading (ABT) program will help achieve these low costs by 

allowing refiners to optimize their investments. And that low cost estimate assumes that less than 

a quarter of the 111 existing refiners will participate in the ABT program. 

Commenter: ExxonMobil

If the Agency decides to proceed with this rulemaking, we recommend that EPA retains the 

flexibility of the Averaging, Trading, and Banking program with the additional modifications 

submitted by API and AFPM; 

Commenter: Marathon Petroleum Company LP (MPC)

In general, MPC supports the sulfur Averaging, Banking, and Trading program concept but has 

some specific recommendations to improve the proposal. 

MPC supports the inclusion of an ABT program as part of the Tier 3 regulations.

Commenter: Natural Resources Defense Council (NRDC)

EPA’s proposal provides generous flexibilities for the meeting the sulfur requirements. The 

proposed averaging, banking and trading (ABT) program minimizes cost of compliance by 
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allowing for investments in the most efficient locations and through early credit generation 

opportunities that allow refiners to spread out investments. 

Commenter: Phillips 66 Company

Credit, Banking and Trading - We support an early credit generation provision. 

Our Response:

Consistent with our proposal, we are finalizing a nationwide ABT program as part of the 

final Tier 3 program. We believe that the ABT program provides flexibility will help enable the 

January 1, 2017 start date for the gasoline sulfur standards. Details of the ABT program can be 

found in Section V.D of the preamble to the final rule, and specific elements of the ABT 

program that we received comments on are also discussed below in Chapters 5.5.2.2 through 

5.5.2.5.

Regarding the commenter’s concern that our modeling is optimistic, based on our 

analysis of the Tier 2 credit trading market (see RIA Chapter 4.3.2) and current refinery sulfur 

levels (RIA Chapter 4.4), we believe that there will be sufficient credits in the marketplace and 

that there will be both intra- and inter-company trading. As discussed in more detail below, the 

Tier 3 ABT program will flow seamlessly from the Tier 2 ABT program. Tier 2 “banked” 

credits will be able to receive their full credit life, and credits generated prior to January 1, 2017 

will be relative to the current (Tier 2) 30 ppm sulfur standard. Further, these credits can be used 

for compliance with either the Tier 2 or Tier 3 programs. Current refinery sulfur levels indicate 

that there are refineries near, and even below, 10 ppm; thus, we anticipate that these refineries 

will all be able to generate credits for overcompliance with the 10 ppm sulfur standard beginning 

January 1, 2017. Considering all of these factors, we believe that there will be sufficient credits 

available for those needing (or choosing) to defer investment to better align with their existing 

turnaround schedules or financial needs.

We received comments both expressing concerns that the ABT program will hinder the 

efforts of the Tier 3 program, and expressing concern that the Agency should not rely on the 

ABT program – it should be an option available to refiners, not a requirement. We note that the 

success of the Tier 2 gasoline sulfur program occurred with a nationwide ABT program. The 

Tier 3 program will simply continue this ABT program, just relative to a 10 ppm standard 

instead of 30 ppm. We considered, but quickly rejected, other compliance options for the Tier 3 

program that included for example, a fixed date for all refineries with no ABT or other 

flexibilities. Without this flexible ABT program, a January 1, 2017 start date of the program 

may not have been feasible and would have caused impacts to the fuel refining industry that

could have negative supply or pricing impacts. However, this would have gone counter to our 

successful approaches in implementing prior fuel standards, and counter to refiner support for an 

ABT program. We could also have designed it with a declining sulfur standard each year 

beginning in 2014. However, that would have required a rigid phase-down of the sulfur levels 

between now and 2020. In contrast, the program as finalized allows the industry to determine 

the most cost-effective way to phase-down sulfur levels between now and 2020. Finally, we 

believe that it is entirely appropriate to consider the flexibilities when considering the start date 
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for the fuel standards. The Agency has always taken into consideration the flexibility afforded 

by the ABT programs in setting the start date for its standards, and in fact has argued that it is 

legally required to in the context of some of vehicle and engine programs where we are obligated 

to set the most stringent standards feasible considering cost and other factors. Incorporating 

ABT provisions allows the Agency to set standards that are less costly and can achieve benefits 

sooner than might otherwise be possible. 

5.5.2.2 Who Can Generate Credits

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA has also requested comment on its proposal that sulfur credits only be generated for 

gasoline that is subject to the proposed sulfur requirements as described at §80.1603. This 

approach would exclude gasoline designated for export and California, but would include 

gasoline produced by California refineries for use outside the state. California gasoline is not 

covered by EPA’s proposed rule. The Agency has requested comment on whether to include 

California gasoline in the averaging, banking and trading program under Tier 3 (not the early 

credit program) (57). 

We agree with EPA that sulfur credits may only be generated for gasoline that is subject to the 

proposed sulfur requirements as described at §80.1603. However, California gasoline should not 

be included in the ongoing ABT program under Tier 3. California gasoline has a 20 ppm per 

gallon cap at retail and market fuels have averaged 10 or less for several years (58). Allowing 

federal credits for improvements done long ago to meet CARB requirements serves only to dilute 

the federal program. In addition, refiners should only be granted credits if EPA also reduces the 

refinery gate and retail per gallon caps well below Tier 2 levels. 

57 - 78 Fed. Reg. 29908 at 29873 (May 21, 2013). To be consistent, if EPA were to grant the oil industry 

sulfur credits for California gasoline sold, it should also grant OEMS federal NMOG credit for CA 

vehicles sold in CA and 177 states.

58 - 78 Fed. Reg. 29908 at 29820 (May 21, 2013).

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Furthermore, we also agree with EPA that over-compliance with the DFE per-gallon cap is not a 

valid basis for credit generation (59). EPA should only allow credit generation were it to impose 

an additional annual average sulfur standard for DFE (denatured fuel alcohol) at some level 

below 10 ppm, and allow credits to be generated for over-compliance with that standard. 

59 - 78 Fed. Reg. 29908 at 29820 (May 21, 2013).

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 
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Manufacturers (AFPM)

We do not agree with EPA’s statement in the preamble that credit generation should be limited to 

refiners who produce gasoline from crude oil. Instead, any refiner that meets the definition of 

80.2(i), which includes parties who combine blendstocks to produce gasoline, should be eligible 

to generate both early and standard Tier 3 credits. We note that the regulatory text at 

80.1615(a)(1) does not appear to restrict credit generation to refiners who produce gasoline from 

crude oil. Therefore, we believe the preamble should be changed to remove the reference to 

producing gasoline by processing crude oil. Refiners who produce gasoline by combining 

components are allowed to generate credits under Tier 2. The Tier 3 program should not remove 

this provision since component blenders should be incentivized to produce gasoline that overcomplies with the Tier 3 standard. 

We do agree that U.S. importers of gasoline should be eligible to generate both early and 

standard credits. Other parties who are not refiners or importers of gasoline should not be eligible 

to generate credits. We believe that including other parties, like ethanol producers and oxygenate 

blenders, will add needless complexity to the program without generating any benefits. All of the 

gasoline entering the U.S. market can be covered under the proposed program structure. 

Similarly, we support the prohibition against ownership of credits by any party who is not a 

registered refiner or importer. 

We agree with the proposal that gasoline designated for export and California gasoline should 

both be excluded from the Tier 3 program and should not be allowed to generate credits. While 

some California gasoline could generate Tier 3 credits and provide some compliance flexibility, 

imposing a 10 ppm sulfur average on California gasoline adds an additional blending constraint 

to supplying the challenging California market. We do not believe that the additional Tier 3 

flexibility justifies this additional burden for the producers of California gasoline. Gasoline 

refined in California and shipped to another state under Tier 3 should be subject to the same 

regulatory framework that currently exists today. 

Commenter: Chevron Products Company

We agree that both U.S. refiners and U.S. importers of gasoline should be eligible to generate 

both early and standard credits. Other parties who are not refiners or importers of gasoline should 

not be eligible to generate credits. We believe that including other parties, like ethanol producers, 

will add needless complexity to the program without generating any benefits. All of the gasoline 

entering the U.S. market can be covered under the proposed program structure. Similarly, we 

support the prohibition against ownership of credits by any party who is not a registered refiner 

or importer. 

It is important to maintain the current rules for participation in the program. Entities who are not 

producers or importers of gasoline and who are not regulated under Tier 3 should not be allowed 

to participate in the ABT program. 

We agree with the proposal that gasoline designated for export and California gasoline should 

both be excluded from the Tier 3 program and should not be allowed to generate credits. While 
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some California gasoline could generate Tier 3 credits and provide some compliance flexibility, 

imposing a 10 ppm sulfur average on California gasoline adds an additional blending constraint 

to supplying the already challenging California market. We do not believe that the additional 

Tier 3 flexibility justifies this additional burden for producers of California gasoline. Gasoline 

produced in California for sale outside the state should continue to be included in the program. 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

In the Preamble that accompanied the proposed regulations, EPA explained that it is the 

Agency’s plan to limit both credit generation and ability to hold title to generated credits to 

companies required to comply with the proposed Tier 3 sulfur standards – refiners and importers. 

These limitations are designed to prevent abuse and fraud. The Association agrees with EPA and 

believes that such an approach would promote the integrity of (i) credit generation and use, and 

(ii) the overall program. 

EPA is proposing to encourage early gasoline desulfurization and to give members of the 

refining industry flexibility to stagger their investments. Therefore, under the proposed rule, EPA 

would allow refiners and importers to generate early credits for “over-complying” with the 

current 30 ppm gasoline sulfur standard on a volume-weighed annual average basis from January 

1, 2014 through December 31, 2016. These early credits would have a limited credit life; they 

could be used to demonstrate compliance for three years – 2017, 2018, and 2019. EPA has asked 

for comments on whether importers should be eligible to generate early credits because they do

not make investments in refinery modifications to meet the proposed Tier 3 standard. 

Members of the Association strongly support EPA’s proposal to allow importers, as well as 

refiners, to generate early credits for several reasons: 

First, eligibility for such credits would encourage importers to maximize their efforts to bring 

lower sulfur gasoline into the United States. These efforts would result in greater volumes of 

lower sulfur gasoline on the market sooner and help EPA meet its objective of better air quality 

at the earliest possible date; 

Second, the greater the number of early credits available, the greater the flexibility U.S. refiners 

would have in making the needed investments in their facilities; and 

Third, EPA is correct that importers do not, themselves, make financial investments in 

desulfurization equipment. However, when importers purchase lower sulfur gasoline abroad, 

they pay a premium for this fuel, reflecting the financial investment made by the foreign refiner. 

Thus, importers are essentially making an investment, similar to domestic refiners, when they 

import lower sulfur fuel into U.S. commerce. 

Commenter: Irving Oil Terminals Inc.

Irving Oil strongly supports the generation of early credits by both refiners and importers. 

Commenter: Magellan Midstream Partners, L.P.
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Early Sulfur Credits — EPA has proposed program flexibility through an average, banking and 

trading program. 

Magellan Comment - EPA has limited its proposal to allow only crude oil refiners and importers 

to generate early credits. We believe any refiner that meets the definition of 80.2(i), which 

includes parties who combine blendstocks to produce gasoline, should be eligible to generate 

both early and standard credits under the proposed rule. For example, importers are not required 

to produce gasoline from crude oil refining and could be producing it by blending, and yet they 

are allowed to generate early credits. In addition, the primary reason for allowing importers to 

generate early credits because there is no baseline required. This is also applicable to a domestic 

gasoline blender. 

The preamble also mentions the inclusion of importers in the generation of early credits allows 

domestic refiners more time to make capital investments to reduce sulfur in gasoline. Allowing 

domestic blenders to generate early credits would have the same impact. 

Commenter: Marathon Petroleum Company LP (MPC)

We do not agree with EPA’s statement in the preamble that credit generation should be limited to 

refiners who produce gasoline from crude oil. Instead, any refiner that meets the definition of 

80.2(i), which includes parties who combine blendstocks to produce gasoline, should be eligible 

to generate both early and standard Tier 3 credits. We note that the regulatory text at 

80.1615(a)(1) does not appear to restrict credit generation to refiners who produce gasoline from 

crude oil. Therefore, we believe the preamble should be changed to remove the reference to 

producing gasoline by processing crude oil. Refiners who produce gasoline by combining 

components are allowed to generate credits under Tier 2. The Tier 3 program should not remove 

this provision since component blenders should be incentivized to produce gasoline that overcomplies with the Tier 3 standard. 

We do agree that U.S. importers of gasoline should be eligible to generate both early and 

standard credits. Other parties who are not refiners or importers of gasoline should not be eligible 

to generate credits. We believe that including other parties, like ethanol producers and oxygenate 

blenders, will add needless complexity to the program without generating any benefits. All of the 

gasoline entering the U.S. market can be covered under the proposed program structure. 

Similarly, we support the prohibition against ownership of credits by any party who is not a 

registered refiner or importer. 

We agree with the proposal that gasoline designated for export and California gasoline should 

both be excluded from the Tier 3 program and should not be allowed to generate credits. While 

some California gasoline could generate Tier 3 credits and provide some compliance flexibility, 

imposing a 10 ppm sulfur average on California gasoline adds an additional blending constraint 

to supplying the challenging California market. We do not believe that the additional Tier 3 

flexibility justifies this additional burden for the producers of California gasoline. Gasoline 

refined in California and shipped to another state under Tier 3 should be subject to the same 

regulatory framework that currently exists today. 
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Commenter: Northeast States for Coordinated Air Use Management (NESCAUM)

It is not appropriate to allow ethanol producers or blenders to generate sulfur credits under the 

proposed gasoline sulfur program. This would require expansion of the program’s sampling, 

testing, recordkeeping, and reporting requirements and require ethanol producers and blenders to 

be treated as refiners. This expansion of the program to include non-obligated parties would 

unnecessarily complicate the program with no corresponding benefit. 

Commenter: Phillips 66 Company

We support refineries and importers being able to generate credits. This would include entities 

that meet the definition of a refinery through creation of finished gasoline via blendstock 

blending. These “refineries” have to meet the standards, sampling and testing, and reporting 

requirements. In order to generate credits, they would need to secure very low sulfur blendstocks 

and should be allowed to generate credits. We also agree that other entities (e.g., oxygenate 

blenders) should not be allowed to generate credits. 

The proposed rule continues to exempt California gasoline from the federal gasoline sulfur 

regulation, however, EPA asked for comment on whether to include California gasoline in the 

ongoing ABT program under Tier 3. Phillips 66 agrees that the California gasoline volumes 

(CARB gasoline) should not be included under the Tier 3 provisions but we provide an 

alternative option for consideration. We ask EPA to consider an opt-in provision whereby a 

California refinery could chose to have its CARB gasoline volumes subject to the Tier 3 

standards and requirements. If a refinery opted in, all of their CARB gasoline would be subject to 

the 10 ppm average sulfur standard and they would be able to generate credits against the 10 

ppm standard. 

Commenter: Renewable Fuels Association (RFA)

As detailed above, RFA believes DFE producers should be exempt from onerous sulfur content 

batch reporting requirements. However, if EPA’s final rule requires ethanol producers to 

report sulfur content by batch (as proposed), they should be allowed to participate in sulfur credit 

averaging, banking, and trading (ABT) program. Ethanol has value for its sulfur reduction 

ability. As larger volumes of ethanol enter the marketplace, EPA should allow ethanol 

manufacturers the option to capture the value to the marketplace through the dilution of sulfur 

from ethanol that contains below 10ppm sulfur. The option to bank and trade sulfur credits 

would come with the regulatory reporting requirements of the Sulfur banking and trading 

program imposed on oil refiners. 

Commenter: Shell Oil Products for Shell and Motiva

EPA should allow all “refiners,” Including Gasoline Blenders, To Participate in the Credit 

Generation Program.
Tier 3 Summary and Analysis of Comments

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We generally support EPA’s proposed averaging, banking and trading provisions. These 

provisions provide important flexibility that should help the industry reduce compliance costs. 

We do not agree, however, with one of the restrictions that EPA proposes – only refineries that 

process crude oil are eligible to generate credits. That is an unnecessary limitation that unfairly 

excludes gasoline blenders. If a gasoline blender – classified as a refiner under EPA’s rules – is 

able to secure low sulfur blend stocks and supply lower sulfur gasoline to the market, EPA 

should encourage it. By not allowing gasoline blenders to generate credits, EPA is unnecessarily 

foregoing the emission reductions that could result from such parties supplying lower sulfur 

gasoline and it deprives the entire industry of credits that could help the entire industry meet 

EPA’s aggressive compliance schedule. 

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

EPA proposes that refiners and importers be able to generate credits through early compliance 

and over-compliance. Only ‘Obligated Parties’ (refiners, blenders and importers) may generate, 

use, transfer or own early or standard credits. Though we acknowledge that the same entities are 

implicated under the RFS, we encourage EPA to use a term other than ‘Obligated Parties’ to 

describe the parties capable of generating credits to avoid confusion. The use of such term is 

unnecessarily confusing as Obligated Parties cannot generate credits under the RFS, and have 

entirely different obligations under the RFS than they would under the Proposed Rule. 

Commenter: Weaver and Tidwell LLP

Under this section [80.1615(a)], only refiners and importers may earn credits under Subpart O. 

Weaver believes that butane blenders and transmix processors should be included in this list. 

Commenter: Countrymark

the rule. This is important to the CountryMark because we own and operate the refining and 

terminal assets.

Commenter: Small Business Refiners (SBR)

Credit generation should be permitted only for the obligated party as defined in the rule. This is 

important to the SBRs because we own and operate the refining and terminal assets. 

Commenter: American Coalition for Ethanol (ACE)

On a related note, ACE also believes that ethanol producers should be eligible to generate credits 

under the gasoline sulfur program. EPA states that ‘since many refiners currently comply with 

our standards taking into consideration the fuel property changes expected as a result of 

downstream ethanol blending, providing ethanol blenders with sulfur credit would result in 

double counting the effects of ethanol.’ Actually, giving sulfur credit to ethanol producers would 

apply credit to the fuel supplier that is actually reducing sulfur, as opposed to forcing ethanol 

producers to give that benefit away to refiners, who will use it to delay reducing sulfur in 
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gasoline. Regardless of the mechanism used, ACE does not believe EPA should provide refiners 

with pathways that allow delayed adoption of cleaner fuel standards, and we particularly object 

to the suggestion that the ethanol industry should enable that delay at our own expense. 

Commenter: Growth Energy

If DFE will have the same batch testing and registration requirements as gasoline, requiring a10 

ppm sulfur cap versus an average could disadvantage DFE versus gasoline, which can generate 

and profit from sulfur credits. DFE having the same sulfur limits as gasoline, along with a 

compliant petroleum blendstock, will result in ethanol blends having a sulfur limit that is 

identical to the proposed finished gasoline specifications. 

Furthermore, if the burden of implementing batch testing and reporting is imposed on ethanol 

producers, they should be allowed to generate sulfur credits. EPA states that “While certain 

batches of ethanol could theoretically be low enough in sulfur to generate credits, it is our desire 

to limit credit generation to companies required to comply with the proposed Tier 3 sulfur 

standards, i.e., refiners and importers.’

If DFE producers are required to complete the batch testing, reporting, and record keeping on 

DFE similar to refiner requirements on gasoline, they should have the same ability to generate or 

use credits. 

EPA mistakenly states that “since many refiners currently comply with our standards taking into 

consideration the fuel property changes expected as a result of downstream ethanol blending, 

providing ethanol blenders with sulfur credit would result in double counting the effects of 

ethanol.” However, double counting would not result if refiners are assuming that DFE has a 

sulfur level of 10 ppm. Credits would only be generated at levels that are below this 10 ppm 

level. 

EPA attempts to further reject ethanol generating sulfur credits by stating that “Over compliance 

with the per-gallon cap would not be a valid basis for credit generation, as you would expect that 

in all cases the DFE would be below the cap. To allow credit generation, we would need to 

propose an additional annual average sulfur standard for DFE at some level below 10 ppm, and 

allow credits to be generated for over compliance with that standard.” Ethanol producers should 

have the same ability to generate credits if they have the same testing and reporting standards. In 

order to remain price-competitive with gasoline, ethanol should be allowed to generate credits in 

a similar manner as gasoline. Furthermore, such credit trading could allow ethanol producers to 

offset the cost of [new] DFE testing and reporting requirements. 

Commenter: POET, LLC

If DFE will have the same batch testing and registration requirements as gasoline, requiring a 10 

ppm sulfur cap versus an average could disadvantage DFE versus gasoline which can generate 

and profit from sulfur credits. DFE having the same sulfur limits as gasoline, along with a 

compliant petroleum blendstock, will result in ethanol blends (whether MLEBs or HLEBs) 

having a sulfur limit that is identical to the proposed finished gasoline specifications. 
Tier 3 Summary and Analysis of Comments

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Furthermore, if the burden of implementing batch testing and reporting is imposed on DFE 

producers, they should be allowed to generate sulfur credits. EPA states that ‘While certain 

batches of ethanol could theoretically be low enough in sulfur to generate credits, it is our desire 

to limit credit generation to companies required to comply with the proposed Tier 3 sulfur 

standards, i.e., refiners and importers.’ (70) If DFE producers are required to complete the batch 

testing, reporting, and record keeping on DFE similar to refiner requirements on gasoline, they 

should have the same ability to generate or use credits. 

EPA mistakenly states that ‘since many refiners currently comply with our standards taking into 

consideration the fuel property changes expected as a result of downstream ethanol blending, 

providing ethanol blenders with sulfur credit would result in double counting the effects of 

ethanol.’ (71) However, double counting would not result if refiners are assuming that DFE has a 

sulfur level of 10 ppm. Credits would only be generated at levels that are below this 10 ppm 

level. 

EPA attempts to further reject ethanol generating sulfur credits by stating that ‘Over compliance 

with the per-gallon cap would not be a valid basis for credit generation, as you would expect that 

in all cases the DFE would be below the cap. To allow credit generation, we would need to 

propose an additional annual average sulfur standard for DFE at some level below 10 ppm, and 

allow credits to be generated for over compliance with that standard.’ (72) Ethanol producers 

should have the same ability as refiners to generate credits if they have the same testing and 

reporting standards. In order to remain price-competitive with gasoline, ethanol should be 

allowed to generate credits in a similar manner as gasoline. Furthermore, such credit trading 

could allow ethanol producers to offset the cost of new DFE testing and reporting requirements. 

70 - Id. at 29,938.

71 - Id.

72 - Id. at 29,938-39.

Our Response:

Use of the Term “Obligated Parties”

With respect to comments requesting that EPA not use the term “obligated party” in the 

Tier 3 regulations, we agree with these comments and are using the terms “refiner” and 

“importer” in the final Tier 3 regulations. The Tier 2 rule was finalized in 2000, and used this 

term as a general way to refer to regulated parties such as refiners and importers. However, this 

term now has a very specific meaning under the RFS program. The use of “obligated party” in 

the Tier 3 proposed regulations was to remain consistent with the Tier 2 regulations; however, 

we agree that this could cause confusion with the RFS program.

Participation in the ABT Program

Consistent with our proposal, gasoline sulfur credits may be generated by U.S. refiners, 

and importers of gasoline into the U.S., only for gasoline that is subject to the sulfur 

requirements as described in the regulations at §80.1603. This provision excludes gasoline 

produced or imported for use in California (“California gasoline”) and gasoline designated for 
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export, but includes gasoline produced by California refineries for use outside the state. Further, 

importers will also be able to participate fully in ABT program, so they will be able to generate 

credits for sending over-compliant gasoline to the U.S. This is unlike other previous and existing 

fuel programs that precluded their participation in the early credit portion of an ABT program.

In response to comments, we have revised the regulations by removing the terms 

“produce gasoline from crude” from §80.2(i). Under the final Tier 3 program, refiner-blenders 

who comply with the full suite of sampling, testing, and reporting requirements can participate in 

the Tier 3 ABT program. Additionally, we are extending these provisions to butane and pentane 

blenders (per Section V.I of the preamble to the final rule) if they likewise comply with the full 

suite of sampling, testing, and reporting requirements. However, any refiner-blender who uses 

the reduced sampling, testing, and reporting provisions for blending butane or pentane into 

gasoline will not be allowed to generate Tier 3 credits.

Consistent with our proposal, ethanol and oxygenate producers are not allowed to 

participate in the Tier 3 ABT program. As discussed in Section V.G.4 of the preamble to the 

final rule, and consistent with existing EPA fuel programs, we continue to believe that it is not 

appropriate expand the ABT provisions to cover ethanol producers and oxygenate blenders for 

several reasons. First, expanding the ABT program beyond refiners and importers could greatly 

increase the number of parties participating thereby potentially complicating EPA compliance 

assurance activities while having little overall impact on the sulfur credit pool. Second, the 

current ABT program under the Tier 2 gasoline sulfur program, which is limited to gasoline 

refiners and importers, has functioned effectively with few compliance irregularities. Third, 

experience with the unleaded gasoline program suggests widespread abuse and fraud when 

credits have been allowed to be generated or sold by parties other than refiners or importers 

subject to the regulations. Fourth, it would require a considerably more complicated compliance 

structure, including the application of all refiner responsibilities to ethanol producers and 

blenders. Fifth, there is no need for denatured fuel ethanol (DFE) producers to generate credits 

in order to recoup the value for any lower sulfur content of their product. The value of any lower 

sulfur content will be reflected in the market price of DFE, similar to the octane value to refiners. 

Sixth, the sulfur ABT provisions were included to ease the burden of compliance for refiners 

who have to make capital changes to their facilities to meet the more stringent Tier 3 sulfur 

standards. In addition to reducing the cost of the Tier 3 gasoline sulfur program, the ABT 

provisions allow for an earlier effective date of the sulfur standards than would otherwise be 

possible. Such considerations are not applicable to ethanol producers since capital expenditures 

for desulfurization equipment or other equipment will not be needed at their facilities to comply 

with the final Tier 3 sulfur standards.14 Finally, overcompliance with the per-gallon sulfur cap 

for DFE is not a valid basis for credit generation. We expect that in all cases, the DFE sulfur 

level will be below 10 ppm. To allow credit generation for these parties, we would need to set 

an additional annual average sulfur standard for DFE at some level below 10 ppm and allow 

credits to be generated for overcompliance with that standard. Accordingly, we do not believe it 

is appropriate to allow ethanol producers or blenders to generate sulfur credits under the Tier 3 

gasoline sulfur program, and as such, we did not finalize such a provision. The Tier 3 rule 

prohibits any person downstream of the refinery or importer that produced or imported gasoline, 

 
Tier 3 Summary and Analysis of Comments

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CBOB, or RBOB who adds oxygenate to such product from including the volume and sulfur 

content of the oxygenate in any compliance calculations for credit generation.

5.5.2.3 Design of Credit Program

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

We generally agree with the structure of the standard credit generation program, allowing credits 

to be generated for gasoline that over-complies with the 10 ppm annual average standard. Credits 

should be generated annually on a calendar year compliance period.

We support the inclusion of a special period of credit generation from 2014 to 2016 to facilitate 

the transition from Tier 2 to Tier 3. We agree that the program should be available to refiners and 

importers, and agree with the structure of generating credits against the current 30 ppm standard 

with no individual refinery baseline. However, the ability to generate credits during this period 

does not guarantee that sufficient credits will be available to allow refiners to broadly defer 

investments past the proposed January 1, 2017 implementation date. EPA has described a very 

optimistic scenario for refineries to generate credits by operating existing pre-treaters and posttreaters at sub-30 ppm gasoline levels in 2014-16. If refineries fail to meet these optimistic 

predictions, credit availability might be limited and will hinder the industry transition to the 10 

ppm standard in 2017. 

During the 2014-2016 period, we do not agree with the proposed structure of the early credit 

program and instead recommend a different program structure to transition from the current Tier 

2 program to the start of the Tier 3 program. We believe that any refinery should be able to 

generate credits against the 30 ppm standard during the 2014-2016 period, and that these credits 

should have a 5 year life. Credit generators should not have to designate these credits as either 

Tier 2 or Tier 3 credits. The party who holds a credit generated in 2014-2016 should be able to 

use the credit for compliance with Tier 2 standards or bank the credit for future use with Tier 3. 

By granting these credits a 5 year life and by allowing a party to bank these credits for future 

Tier 3 use, the refiner or importer is incentivized to reduce the sulfur content of their gasoline 

pool. This could maximize the removal of sulfur from the pool even in advance of the Tier 3 

program. No transition from Tier 2 Standard Credits to Tier 3 Early Credits to Tier 3 Standard 

Credits would be required. This single credit program would be easier for EPA to manage and 

enforce compared to implementation of an early credit program. 

If EPA finalizes the early credit program as proposed, we do not agree that refiners should have 

to designate credits generated from 2014 to 2016 as either Tier 2 credits or Tier 3 early credits. 

We believe that these credits, generated against the 30 ppm standard, should be allowed to be 

used for either Tier 2 or Tier 3 compliance without prior designation by the generating party. 

Generated credits could accrue undesignated in the party’s account and should be available to be 

freely used for Tier 2 compliance, Tier 3 early compliance, or traded to other parties who could 
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use them for either program. Refiners will not be able to exactly predict their future credit 

requirements and should not be penalized by over or under-designating credits for either 

program. 

In addition, we believe that any party holding Tier 2 credits at the end of 2016 should be allowed 

to convert these Tier 2 credits to Tier 3 early credits, which could be used through 2019. Tier 2 

credits represent real sulfur reductions against the existing standard which are a benefit to the 

environment. The owners of these credits should be able to preserve their value by applying them 

in the early years of the Tier 3 program. 

Should EPA decide to proceed with the proposed credit designation of Tier 2 or Tier 3 during the 

early generation credit period, we recommend that such declaration is made by February 28th of 

the following year, consistent with compliance reporting. 

The benefits of averaging banking and trading of the Tier 2 rule are not comparable to Tier 2.

The opportunity to generate credits is limited by a refinery’s existing equipment and 

configuration. Tier 2 sulfur credits are still in circulation, and it would be beneficial, and we 

request that EPA publish aggregate data on the remaining Tier 2 sulfur credit balances in order to 

determine to what extent an ABT program would provide or could provide a benefit.

With such a short lead time, the opportunity to generate sufficient credits to cover both the Tier 2 

requirements and bank credits for Tier 3 between now and January 2017 will be limited. 

Commenter: Chevron Products Company

We agree with the format of the ABT program. We generally agree with the structure of the 

standard credit generation program, allowing credits to be generated for gasoline that overcomplies with the 10 ppm annual average standard. Credits should be generated annually on a 

calendar year compliance period. 

We do agree with the inclusion of a credit averaging, banking, and trading (ABT) program, 

including a three-year phase-in period from 2014 through 2016 with the ability to generate early 

credits. However, we propose some changes to the details of the ABT program which are 

described below. 

We support the inclusion of a special period of credit generation from 2014 to 2016 to facilitate 

the transition from Tier 2 to Tier 3. We agree that the program should be available to refiners and 

importers, and agree with the structure of generating credits against the current 30 ppm standard 

with no individual refinery baseline. However, the ability to generate credits during this period 

does not guarantee that sufficient credits will be available to allow refiners to broadly defer 

investments past the proposed January 1, 2017 implementation date. EPA has described a very 

optimistic scenario for refineries to generate credits by operating existing pre-treaters and posttreaters at sub-30 ppm gasoline levels in 2014-16. If refineries fail to meet these optimistic 

predictions, credit availability might be limited and will hinder the industry transition to the 10 

ppm standard in 2017. 
Tier 3 Summary and Analysis of Comments

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We do not agree with the proposed structure of the early credit program during the 2014-2016 

period and instead recommend a different program structure to transition from the current Tier 2 

program to the start of the Tier 3 program. We believe that any refinery should be able to 

generate credits against the 30 ppm standard during the 2014-2016 period, and that these credits 

should have a 5 year life. Credit generators should not have to designate these credits as either 

Tier 2 or Tier 3 credits. The party who holds a credit generated in 2014-2016 should be able to 

use the credit for compliance with Tier 2 standards or bank the credit for future use with Tier 3. 

By granting these credits a 5 year life and by allowing a party to bank these credits for future 

Tier 3 use, the refiner or importer is incentivized to reduce the sulfur content of their gasoline 

pool. This could maximize the removal of sulfur from the pool even in advance of the Tier 3 

program. No transition from Tier 2 Standard Credits to Tier 3 Early Credits to Tier 3 Standard 

Credits would be required. This single credit program would be easier for EPA to manage and 

enforce compared to implementation of an early credit program. 

If credits must be designated as Tier 2 or Tier 3, we believe that the program should 

acknowledge the transition from Tier 2 to Tier 3 by allowing unused Tier 2 credits to be 

converted to Tier 3 credits after 2016. Under the current proposal, all Tier 2 credits will become 

stranded if they are not used by the end of the 2016 compliance year. The Tier 2 credits represent 

real sulfur reductions in gasoline below the required standard which in turn generated 

environmental benefits beyond the requirements of Tier 2. Refiners and importers should not 

lose the benefit of these credits that were generated by their over-compliance with the Tier 2 

sulfur standard. 

Commenter: CHS, Inc.

Currently under the proposed Tier 3 regulation, sulfur credits generated under the Tier 2 

regulation for the years 2012 and 2013 can only be used for compliance through the calendar 

year 2016. CHS requests that the EPA allow these Tier 2 sulfur credits to be used to demonstrate 

compliance for years 2017 and 2018. This will help ensure that refineries meet compliance and 

ultimately protect the consumer from any supply disruptions. 

Commenter: Irving Oil Terminals Inc.

In addition, EPA has recognized that early credits generated by both refiners and importers will 

help industry comply with the new standard and ensure that lower sulfur gasoline is available as 

quickly as possible. Early credits also help to advance the associated environmental and health 

benefits to an earlier timeframe. With some companies already having the ability to meet the 

proposed lower standard, the EPA should begin the early credit program at a minimum of five 

years before the effective date. 

Irving Oil does not think that the compliance timetable of three years is adequate to meet the Tier 

3 sulfur content standard. The use of early credits would certainly provide some flexibility with 

refinery project execution in order to meet the requirements of the proposed standard. In 

addition, early credits would help bring greater volumes of lower sulfur gasoline to market 

earlier and address concerns from the auto manufacturers. Irving Oil strongly supports the 
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generation of early credits by both refiners and importers. EPA should do everything it can to 

encourage the production and importation of qualified gasoline eligible for these credits. 

It is well known that some refiners and importers need only to make modest adjustments to their 

facilities and/or locate foreign gasoline cargoes in order to incrementally lower their sulfur 

content downward from 30 ppm. The EPA should initiate the early credit program as early as 

possible with a retroactive effective date of January 1, 2013. 

It should be noted that, even with this modification, it is not certain that enough early credits 

would be generated to allow the regulated community to meet the Tier 3 standard by the current 

proposed Effective Date of 2017. However, the more early credits are encouraged, the greater the 

chance more will be available to provide the degree of flexibility EPA has anticipated, thereby 

facilitating compliance with the 10 ppm annual average standard at the earliest possible date. 

Commenter: Marathon Petroleum Company LP (MPC)

We generally agree with the structure of the standard credit generation program, allowing credits 

to be generated for gasoline that over-complies with the 10 ppm annual average standard. Credits 

should be generated annually on a calendar year compliance period. 

We support the inclusion of a special period of credit generation from 2014 to 2016 to facilitate 

the transition from Tier 2 to Tier 3. We agree that the program should be available to refiners and 

importers, and agree with the structure of generating credits against the current 30 ppm standard 

with no individual refinery baseline. However, the ability to generate credits during this period 

does not guarantee that sufficient credits will be available to allow refiners to broadly defer 

investments past the proposed January 1, 2017 implementation date. EPA has described a very 

optimistic scenario for refineries to generate credits by operating existing pre-treaters and posttreaters at sub-30 ppm gasoline levels in 2014-16. If refineries fail to meet these optimistic 

predictions, credit availability might be limited and will hinder the industry transition to the 10 

ppm standard in 2017. 

During the 2014-2016 period, we do not agree with the proposed structure of the early credit 

program and instead recommend a different program structure to transition from the current Tier 

2 program to the start of the Tier 3 program. We believe that any refinery should be able to 

generate credits against the 30 ppm standard during the 2014-2016 period, and that these credits 

should have a 5 year life. Credit generators should not have to designate these credits as either 

Tier 2 or Tier 3 credits. The party who holds a credit generated in 2014-2016 should be able to 

use the credit for compliance with Tier 2 standards or bank the credit for future use with Tier 3. 

By granting these credits a 5 year life and by allowing a party to bank these credits for future 

Tier 3 use, the refiner or importer is incentivized to reduce the sulfur content of their gasoline 

pool. This could maximize the removal of sulfur from the pool even in advance of the Tier 3 

program. No transition from Tier 2 Standard Credits to Tier 3 Early Credits to Tier 3 Standard 

Credits would be required. This single credit program would be easier for EPA to manage and 

enforce compared to implementation of an early credit program. 
Tier 3 Summary and Analysis of Comments

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If EPA finalizes the early credit program as proposed, we do not agree that refiners should have 

to designate credits generated from 2014 to 2016 as either Tier 2 credits or Tier 3 early credits. 

We believe that these credits, generated against the 30 ppm standard, should be allowed to be 

used for either Tier 2 or Tier 3 compliance without prior designation by the generating party. 

Generated credits could accrue undesignated in the party’s account and should be available to be 

freely used for Tier 2 compliance, Tier 3 early compliance, or traded to other parties who could 

use them for either program. Refiners will not be able to exactly predict their future credit 

requirements and should not be penalized by over or under-designating credits for either 

program. 

In addition, we believe that any party holding Tier 2 credits at the end of 2016 should be allowed 

to convert these Tier 2 credits to Tier 3 early credits, which could be used through 2019. Tier 2 

credits represent real sulfur reductions against the existing standard which are a benefit to the 

environment. The owners of these credits should be able to preserve their value by applying them 

in the early years of the Tier 3 program. 

Should EPA decide to proceed with the proposed credit designation of Tier 2 or Tier 3 during the 

early generation credit period, we recommend that such declaration is made by February 28th of 

the following year, consistent with compliance reporting. 

And, we believe that the program should acknowledge the transition from Tier 2 to Tier 3 by 

allowing unused Tier 2 credits to be converted to Tier 3 credits after 2016. Under the current 

proposal, all Tier 2 credits will become stranded if they are not used by the end of the 2016 

compliance year. The Tier 2 credits represent real sulfur reductions in gasoline below the 

required standard which in turn generated environmental benefits beyond the requirements of 

Tier 2. Refiners and importers should not lose the benefit of these credits that were generated by 

their over-compliance with the sulfur standard. 

Commenter: Phillips 66 Company

EPA is overly optimistic on early credit generation capability. 

Secondly, EPA asserts that the Averaging, Banking and Trading program will provide refineries 

with early credits that can be used by refineries that fall outside of the small refinery category to 

postpone their project start-up date. Phillips 66 disagrees with this assessment. We believe EPA 

is being overly optimistic on the capability of refineries to generate and make available sufficient 

credits. 

Phillips 66 supports the inclusion of an early credit generation provision in the regulation and we 

believe these flexibilities combined with a 5-year implementation lead time will enhance the 

chances of a successful implementation of any new standard. As a key implementation 

component, ABT provides both 1) incentives for limited early reductions in gasoline sulfur with 

existing units and 2) important flexibilities for continuing compliance after the final 

implementation date. 
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We offer some suggested modifications to the proposed ABT provisions that we believe will 

provide additional utility. 

- Allow refiners to designate credits generated during the 2014-2016 time period as generic 

sulfur credits and put them into a “bank”.

- Allow refiners to use the generic credits for either Tier 2 compliance or leave them in the bank 

and use them for Tier 3 compliance. 

- Allow any Tier 2 credits in the bank at the end of 2016 (e.g. generated in 2011, 2012, or 2013) 

to be converted into Tier 3 credits. 

Commenter: PBF Energy Inc.

PBF supports the proposed ABT program and will examine our options to generate early credits. 

We ask that the EPA clarify the regulatory language to ensure that the final regulation allows 

refiners to decide on credit use as either Tier 2 or Tier 3 early credits at the time of use. It is 

extremely difficult to forecast future requirements, given the potential for unplanned equipment 

outages. Having to designate credit types prior to actual consumption increases the risk of 

“stranding” credits in a less usable type and is a drawback to the rules as currently proposed. The 

EPA through the current programs can still track the amount and year credits are generated and 

effectively define the credits as to their potential. We see little value in forcing a refiner to 

declare the credit type in advance of consumption. 

Commenter: Weaver and Tidwell LLP

Additionally, the program allows for early credits to be earned. However, the Tier 2 sulfur credit 

inventory is not being addressed. What will happen to the current level of Tier 2 sulfur credits? 

To ignore the Tier 2 program sulfur reductions within the context of the Tier 3 program would 

leave the Tier 2 sulfur decrease (funded by refiners, both large and small) out of the program. 

Thus, the efforts of facilities to comply with Tier 2 are ignored. Weaver recommends that the 

agency allow for the conversion of Tier 2 credits to Tier 3, at some reasonable conversion rate. 

Early credits are valid through February 29, 2020. We believe this date should be changed to 

March 31 (consistent with when the annual compliance reports are due, assuming the deadline is 

changed). 

Commenter: Wyoming Refining Company (WRC)

Some subtle aspects of the proposed rule, however, have the potential of making pre-2020 Tier 2 

compliance more difficult, if not impossible. First, the proposed Tier 3 rule allows refiners to 

generate early Tier 3 credits by lowering their gasoline sulfur below 30 ppm during 2014, 2015 

and 2016. Considering the proposed compliance time frame, WRC expects there will be 

significant demand for Tier 3 early credits that will enable large refiners to delay 10 ppm 

production until 2020. The early credits will most likely be generated by increasing operating 

severity on existing Tier 2 equipment. Most Tier 3 early credits will, therefore, probably not be 

new credits but, instead, will be Tier 2 credits, most of which would have been generated in any 

event, converted into Tier 3 early credits. 
Tier 3 Summary and Analysis of Comments

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This situation will create a shortage in the Tier 2 credit supply on which WRC must depend to 

maintain Tier 2 compliance through 2019. 

It does appear that Tier 2 credits generated prior to 2014 (2013 and earlier), however, will become more abundant starting in 2017 as large refiners transition into Tier 3 production and no 

longer have a need for Tier 2 credits. These ‘dumped’ Tier 2 credits, however, will expire, at the 

latest, in 2018. WRC, therefore, may very well be exposed to a situation in 2019 where abundant 

2013 and earlier Tier 2 credits have all expired and 2014 and later Tier 2 credits have been 

mostly converted into Tier 3 early credits. Non-compliance in 2019 is a very real possibility even 

though the proposed rule intends to extend flexibility to small refiners and small volume 

refineries until 2020. 

Our Response:

As discussed in more detail in Section V.D of the preamble to the final rule, in response 

to comments, we are finalizing a more flexible approach to the ABT program than proposed. We 

believe this will provide for a more seamless transition from the Tier 2 to the Tier 3 credit 

programs, and will provide more certainty of credit availability.

Consistent with our proposal, refiners and importers may begin generating credits on an 

annual average basis January 1, 2014, and continue through December 31, 2016, for 

overcompliance with the current 30 ppm annual average sulfur standard. We believe this simple 

approach is possible because U.S. gasoline was averaging around 30 ppm as we started 

developing the Tier 3 program, based on compliance data. Since refiners and importers would 

need to continue to comply with the existing 30 ppm Tier 2 sulfur standards during this 

timeframe absent Tier 3, they would need to maintain this level of performance on an industry 

average basis. Accordingly, any additional gasoline sulfur reductions beyond 30 ppm will be 

attributed to the proposed Tier 3 program. In response to comments, we are not requiring that 

credits be designated as either Tier 2 or Tier 3 and only used for the program for which they 

were designated. Refiners and importers may use credits generated prior to January 1, 2017 

either for ongoing compliance with the Tier 2 program, or bank them for future compliance with 

the Tier 3 program (within the limits of the credit life restrictions). Essentially, the Tier 2 credit 

generation provisions simply continue, and any credits generated from January 1, 2014 through 

December 31, 2016 that were not used for compliance with the Tier 2 standards would be carried 

over for use in complying with Tier 3. We believe that this will allow for more certainty of 

credit availability before refiners must make their Tier 3 investment decisions, thus reducing the 

cost of the program. It will also avoid any incentive for refiners to use up banked Tier 2 credits 

prior to 2017 causing increased in-use sulfur levels and emissions.

Based on our analysis of the Tier 2 credit market for 2012, we believe that there will be a 

balance of 2012 banked credits equivalent to approximately two months of compliance, and we 

anticipate a similar amount (perhaps more) for 2013. In response to several commenters that 

urged EPA to allow these credits to be able to be used for Tier 3 compliance as well to avoid the 

risk of them being stranded, we are finalizing a provision for these credits to retain their full fiveyear life. We are finalizing this provision for a number of reasons. First, the Tier 2 banked 

credits represent real reductions—refiners and importers are currently generating these credits 
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for overcompliance with the Tier 2 gasoline sulfur standard. Second, allowing these banked 

credits to receive their full five-year credit life will provide more assurance of the credit 

availability for trading for those who need them to comply with Tier 3 without a large capital 

investment. As previously explained, this will allow for more certainty of credits available far 

before making Tier 3 investment decisions, thus reducing the cost of the program. A lack of 

certainty in the credit trading market could lead to refiners banking more credits than usual for 

their own use rather than allowing these credits to be available in the market for trading. As 

shown in our analysis in Chapter 4.3 of the RIA, refiners tend to hold credits as an insurance 

policy until they approach the end of their credit life. If credit-generating refiners continue with 

this approach, credits generated in 2012 and 2013 will likely be available for purchase in 2017 

and 2018 for those refiners that may want to rely on them for compliance (along with additional 

credits generated from 2014 through 2016). Finally, as we anticipate that these credits will be 

equal to about four months of compliance, the allowance of 2012 and 2013 banked Tier 2 credits 

makes for a more flexible program by effectively allowing for a small amount of additional lead 

time without adversely affecting the overall benefits of the Tier 3 program. We believe these 

provisions will allow the Tier 3 program to begin on January 1, 2017, with more certainty 

regarding the availability of credits for those refiners needing (or choosing) to defer investment 

to better align with their existing turnaround/shutdown schedules.

However, one small refiner highlighted an opposite concern—that large refiners may 

hold sulfur credits for their own compliance with Tier 3, drying up the market that small refiners 

can rely on to continue to comply with the Tier 2 standards (through December 31, 2019). While 

we appreciate this concern, we believe it is overstated. Based on our analysis of current sulfur 

credit generation and use, we believe that the 5-year credit life will continue to provide an 

incentive for credits to be made available in the market through 2019 for Tier 2 compliance. In 

fact, since credits generated in 2015 and 2016 cannot be used in 2020 and beyond, there is now 

likely to be an increase in credit availability in the years prior to 2020. 

Under the final Tier 3 ABT program, the credit generation provisions are nearly the same 

as those under the Tier 2 program – in essence, the Tier 2 program simply continues with a lower 

standard below which credits are generated. Refiners and importers are allowed to average 

within and across companies to meet the standard in the most cost-effective manner possible, 

including generating and using credits. Credit generation periods remain 12 months long and 

continue to be synchronized with annual compliance demonstration periods. As noted by one 

commenter, these annual reports (which will include a refiner or importer’s credit generation and 

use information) will be due on March 31 of each year, not February 28.

Please see our response to Chapter 5.5.2.4, below, for a detailed discussion of the final 

credit life and credit trading provisions.

5.5.2.4 Credit Use – Credit Trading and Credit Life

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 
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Automakers (Global)

We concur with EPA providing a three-year life for sulfur credits (60). The proposed three-year 

early credit life provision would be consistent with the duration of the small volume refinery 

provisions. It is important that when Tier 3 is fully phased in for automakers it is likewise fully 

phased in for refiners, so that the public can fully benefit from its provisions. 

60 - 78 Fed. Reg. 29908 at 29939 (May 21, 2013).

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

We agree with the 5 year standard credit life as proposed, but, as explained above, we believe 

that the proposed 3 year early credit life should be extended to 5 years. And, we believe that the 

program should acknowledge the transition from Tier 2 to Tier 3 by allowing unused Tier 2 

credits to be converted to Tier 3 credits after 2016. Under the current proposal, all Tier 2 credits 

will become stranded if they are not used by the end of the 2016 compliance year. The Tier 2 

credits represent real sulfur reductions in gasoline below the required standard which in turn 

generated environmental benefits beyond the requirements of Tier 2. Refiners and importers 

should not lose the benefit of these credits that were generated by their over-compliance with the 

sulfur standard. 

We do not believe the maximum two trade limitation on sulfur credits is required. The credit 

program is primarily protected by limiting participation in the credit program to refiners and 

importers. The two trade limitation reduces market liquidity without providing a significant 

enforcement benefit. Multiple sales transactions of the same credits within this small community 

can be adequately tracked with commercial documentation and EPA reporting. To maintain 

integrity of the sulfur credit program, the prohibition on outside parties taking ownership of 

credits should absolutely be preserved, but the two trade limitation could be eliminated. 

Should EPA decide to proceed with two trade limitation, we recommend that EPA clarifies and 

clearly states that there are no restrictions to transferring credits within a refiner/refining 

company. 

Commenter: Chevron Products Company

Credits should be allowed to be traded between companies who are participants in the Tier 3

program. Credits should not be limited to internal transfers between refineries from the same 

company. 

Regarding credit trading, we do not believe the maximum two trade limitation on sulfur credits is 

warranted. The credit program is primarily protected by limiting participation in the credit 

program to refiners and importers. The two trade limitation reduces market liquidity without 

providing a significant enforcement benefit. Multiple sales transactions of the same credits 

within this small community can be adequately tracked with commercial documentation and 
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EPA reporting. To maintain integrity of the sulfur credit program, the prohibition on outside 

parties taking ownership of credits should absolutely be preserved, but the two trade limitation 

should be eliminated. 

Commenter: CHS, Inc.

CHS is providing the following comments regarding the sulfur averaging, banking and trading 

(ABT) program. Currently under the proposed Tier 3 regulation, five year sulfur credits 

generated under the Tier 2 regulation for the years 2012 and 2013 can only be used for 

compliance through the calendar year 2016 thus cutting short the five year credit life. CHS 

requests that the EPA allow these Tier 2 sulfur credits to be used to demonstrate compliance for 

years 2017 and 2018. 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

Early credits should be valid for more than the three years proposed. The 10 ppm annual average 

sulfur standard is an aggressive standard that will take substantial time and money to meet. 

Refiners need as much flexibility as possible, and EPA should do all that it can to maximize (a) 

the number of early credits available, and (b) the value (credit life) of such credits to facilitate 

compliance. Extension of the life of early credits would meet that objective. 

Recommendation: The Association recommends that both refiners and importers have the right 

to generate early credits to help ensure that an adequate volume of such credits is available to 

help refiners stagger their investments to meet the proposed Tier 3 standard. In addition, the life 

of such credits should be 5 years from the date Tier 3 is implemented. 

Permit both refiners and importers to generate early credits to facilitate delivery of lower sulfur 

gasoline into the market at the earliest possible date and to allow such credits to be used for a 

period of 5 years from the date that the Tier 3 regulations become effective; 

Commenter: Irving Oil Terminals Inc.

Irving Oil endorses EPA’s proposal to limit the number of parties who may hold title to Tier 3 

credits. Such a limitation would enhance the ability of regulated parties to assess the validity of 

the credits generated and maintain the integrity of the credit program. 

Moreover, early credits should be valid to demonstrate compliance into 2019, 2020 and 2021. 

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA has proposed that under the Tier 3 ABT program, sulfur credits must be transferred directly 

from the refiner or importer generating them to the party using them for compliance purposes 

(61). This would ensure that the parties purchasing them are better able to assess the likelihood 

that the credits are valid. EPA has allowed an exception so that if a credit generator transfers 
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credits to a refiner or importer who inadvertently cannot use all the credits, the credits can be 

transferred a second time to another refiner or importer. After the second trade, the credits must 

be used or be terminated. We agree that allowing a maximum of two trades is consistent with 

other recent fuel programs and is sufficiently flexible while still preserving adequate means for 

enforcement. One need only look at recent activity in the Renewable Fuel Standard RFS (RIN) 

credit mechanism to know that fraud is a concern, and therefore minimizing the trading of these 

potentially valuable credits is the correct approach. 

61 - 78 Fed. Reg. 29908 at 29940 (May 21, 2013).

Commenter: Marathon Petroleum Company LP (MPC)

We agree with the 5 year standard credit life as proposed, but, as explained above, we believe 

that the proposed 3 year early credit life should be extended to 5 years. 

We do not believe the maximum two trade limitation on sulfur credits is required. The credit 

program is primarily protected by limiting participation in the credit program to refiners and 

importers. The two trade limitation reduces market liquidity without providing a significant 

enforcement benefit. Multiple sales transactions of the same credits within this small community 

can be adequately tracked with commercial documentation and EPA reporting. To maintain 

integrity of the sulfur credit program, the prohibition on outside parties taking ownership of 

credits should absolutely be preserved, but the two trade limitation could be eliminated. 

Should EPA decide to proceed with two trade limitation, we recommend that EPA clarifies and 

clearly states that there are no restrictions to transferring credits within a refiner/refining 

company. 

Commenter: Northeast States for Coordinated Air Use Management (NESCAUM)

Early credits generated under the averaging, banking, and trading (ABT) program should expire 

after three years. The three-year early credit life provision offers sufficient flexibility to refiners 

and still provides a date certain by when automobile manufacturers can be assured that 

introduction of their technology designs correspond with the availability of 10 ppm average 

sulfur gasoline. 

Commenter: Phillips 66 Company

We strongly support limiting ownership of sulfur credits to refiners and importers. This has been 

instrumental in protecting the integrity of the current program. 

- Provide a 5 year life to all credits 

Our Response:

Credit Life
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Under the final Tier 3 ABT program, in response to comments, all credits generated 

before January 1, 2017 will be valid for five years or until December 31, 2019, whichever is 

earlier—no early credits may be used for compliance beginning January 1, 2020. Thus, unlike 

our proposal, banked Tier 2 credits generated in 2012 and 2013 will receive their full five-year 

life and will not expire at the start of the Tier 3 program. However, credits generated in 2015 

and 2016 that are unused as of December 31, 2019 will expire and become invalid. We believe 

that structuring the credit program this way will offer considerable flexibility to refiners phasing 

in Tier 3 gasoline sulfur controls, while still placing a date at which point the intended sulfur 

program will be fully implemented and enforceable—January 1, 2020 (the same date small 

refiners and small refineries must begin complying with the 10 ppm sulfur standard). This will 

also provide a date certain to give auto manufacturers greater confidence for the design of their 

vehicles that all vehicles in-use are running on 10 ppm average fuel. Otherwise, it is possible 

that the greater ease of generating early credits relative to 30 ppm sulfur (as opposed to 10 ppm 

in 2017 and beyond) would allow higher sulfur levels to continue well beyond 2019.

Consistent with our proposal, all credits generated beginning January 1, 2017 will be for 

overcompliance with the Tier 3 10 ppm annual average sulfur standard, and will have a five-year 

credit life. We believe five years will give refiners and importers sufficient time to use credits 

generated in previous years, while still placing limitations on credit life to help with 

enforcement. Five-year credit life is also consistent with the Tier 2 ABT program, as well as the 

current credit life and recordkeeping provisions for other 40 CFR part 80 fuels programs, and 

coincides with the applicable five-year statute of limitations for violations by parties who 

generate invalid credits. Credits must be used within five years from the year they were 

generated (regardless of when/if they are traded), otherwise they will expire and become invalid. 

For example, credits generated in 2017 can be applied towards 2018-2022 compliance, as well as 

2017 compliance. After March 31, 2023 (when reports for the 2022 annual compliance period 

will be due), credits generated in 2017 will expire and become invalid. Similarly, credits 

generated in 2018 can be applied towards 2019-2023 compliance, as well as 2018 compliance. 

After March 31, 2024, credits generated in 2018 expire, and so on and so forth.

Credit Trading

We are finalizing credit trading provisions in the Tier 3 ABT program that are identical to 

those under the current Tier 2 program. As with Tier 2, it is possible that sulfur credits could be 

generated by one party, subsequently transferred or used in good faith by another, and later 

found to have been calculated or created improperly or otherwise determined to be invalid. 

Under the Tier 2 ABT program, as well as other 40 CFR part 80 fuel programs, if this occurs, we 

are requiring that both the seller and purchaser will have to adjust their sulfur calculations to 

reflect the proper credits and either party (or both) could be determined to be in violation of the 

standards and other requirements if the adjusted calculations demonstrate noncompliance with 

the 10 ppm standard. Sulfur credits must be transferred directly from the refiner or importer 

generating them to the party using them for compliance purposes, to ensure that the parties 

purchasing them are better able to assess the likelihood that the credits are valid. However, as 

with the Tier 2 ABT program, there are no prohibitions against brokers facilitating the transfer of 

credits from one party to another. Further, any person can act as a credit broker, regardless of 

whether such person is a refiner or importer, as long as the title to the credits is transferred 
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directly from the generating refiner or importer to the using refiner or importer. We believe that 

maintaining a prohibition on outside parties taking ownership of credits will allow for maximum 

program enforceability and consistency with all of our other ABT programs for mobile sources 

and fuels.

We disagree with comments arguing against the two-trade maximum for inter-company 

trading that exists in the current Tier 2 ABT program. Under the final Tier 3 ABT program, after 

the second trade, credits must be used or they will expire. While some commenters stated that 

they believe the two-trade maximum is not necessary given the fact that credits are only being 

traded within a small part of industry, we believe that unlimited trading could result in an 

unenforceable program and potentially lead to problems with invalid credit trading. Further, 

allowing a maximum of two trades is consistent with other recent fuel programs and we believe 

it is sufficiently flexible while still preserving adequate means for enforcement. Also consistent 

with the Tier 2 program, the provision for unlimited trading for intra-company credits will 

continue. In response to comments, we have clarified this in both the preamble and the 

regulatory text.

5.5.2.5 Deficit Carryforward

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM), Chevron Products Company, Marathon Petroleum 

Company

The deficit carry-forward is an important regulatory flexibility mechanism that is included in the 

Tier 3 regulations but is not discussed in the preamble. We support the inclusion of a deficit 

carry-forward provision in Tier 3. However, we suggest that the deficit carry-forward be 

extended to three years from the current one year. Compliance with the 10 ppm annual average 

will be very challenging for the average refinery. The ability to reduce sulfur significantly below 

10 ppm to make up a compliance deficit in a single year may not be possible, depending on the 

technology and process configuration of the refinery. Credits may or may not be available in the 

market for the refinery to supplement their production of low sulfur gasoline. Extending the 

deficit from one to three years allows the refinery to manage their sulfur production within 

reasonable limits and still maintain the overall integrity of the Tier 3 program. 

In addition, we believe the deficit carry-forward language at 80.1616(a)(6) is in error. It states 

that a refiner should use all available credits before recording a compliance deficit. We believe 

that this requirement should apply to an individual refinery and not to a refiner. A refiner should 

be allowed to carry a deficit at one refinery while having a surplus of credits at another refinery, 

if they so choose. We request EPA to make this correction in the regulations.

Commenter: Phillips 66 Company
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Provide a multi-year deficit carryover provision. Meeting the very stringent 10 ppm average will 

be challenging. An operational issue could persist causing a refinery to not be able to meet the 

standard. Securing sufficient credits or making up the deficit operationally the following year 

may also be very difficult. Allowing a multi-year deficit carryover will be beneficial. We suggest 

allowing a three year deficit carryover rather than just a single year. 

Section 80.1616(a)(6) states that “a refiner possessing credits must use all credits prior to falling 

into a compliance deficit”. The use of “refiner” implies an aggregated company basis. We ask 

that this be changed to be on a refinery specific basis rather than a refiner basis. 

Our Response:

As discussed in the preamble to the final rule, we are finalizing deficit carryforward 

provisions similar to the existing Tier 2 program. An individual refinery that does not meet the 

10 ppm standard in a given year may carry a credit deficit forward for one year, and will have to 

make up the credit deficit and come into compliance with the Tier 3 sulfur standard the next 

calendar year.

Regarding comments requesting that the deficit carryforward allowance be extended to 

two or three years, we disagree with these comments primarily because of concerns with the 

enforceability of a allowing for a deficit beyond one year. Furthermore, an extended deficit 

carryforward could further delay Tier 3 sulfur reductions. However, in recognition of 

unanticipated circumstances, such as where credits are unavailable or are prohibitively expensive 

such that a refiner could not make up the deficit in one year, we are finalizing hardship 

provisions that provide EPA with the authority to allow for extended deficit carryforward if a 

refiner’s hardship petition demonstrates that it meets the required criteria. Thus, as described 

more in Section V.E.2 of the preamble to the final rule, a refiner could carry a deficit forward for 

up to three years only in cases of hardship situations.

We disagree with comments suggesting that the deficit carryforward provisions should be 

applied on a refinery (facility-specific) basis instead of a refiner (company) basis. There is little 

need for a company to carry a deficit for one refinery if it has excess credits from its other 

refineries. But allowing this could defeat the purpose of the one-year restriction, as a refiner 

could simply shift a deficit around from one refinery to another year after year.

5.5.3. Regulatory Flexibility Provisions (Small Refiners and Small Volume Refineries)

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

If EPA implements a small refiner/refinery extension, we recommend that any small 

refiner/refinery holding Tier 2 credits at the end of 2019 should be able to convert these credits 

to Tier 3 credits. Again, these Tier 2 credits represent over-compliance with the Tier 2 standard 
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and would have created a benefit for the environment. The value of these credits should not be 

lost due to expiration. Refiners should not be penalized for failing to predict their exact Tier 2 

credit requirements prior to the end of 2019. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

Standard credit generation by small refiners and small volume refineries should be allowed 

during the 2017-2019 period. The preamble suggests that small refiners would have to 

voluntarily opt in to the Tier 3 program. We note that the proposed regulations do not include 

any obvious reference to this opt-in mechanism. We are not able to comment on whether this 

opt-in would be appropriate without having the regulatory text available to understand how it 

would be implemented. 

Small refinery exceptions are of limited utility if pipelines set lower specifications, which is what 

happened in the Tier 2 rulemaking.

Commenter: Chevron Products Company

If EPA proceeds with the gasoline sulfur reduction, we do support several of the proposed 

elements including: small refinery exemption; 

We agree with the inclusion of an extension of the compliance deadlines for small refiners and 

small refineries as proposed in the Tier 3 NPRM. However, the extension of the compliance 

deadline may not be sufficient to ensure the long term viability of these challenged refineries. 

The Tier 3 capital investment requirements for certain refineries may be economically 

prohibitive regardless of an extension of the start date. EPA should carefully consider the impact 

of the Tier 3 regulations on all refineries and whether additional flexibility measures are 

warranted. 

If the EPA defers the 2017 start date to a later time, the extension for small refiners and small 

refinery owners should be maintained, such that the Tier 3 requirements should apply to small 

refiners and refineries at least three years after the revised start date. 

Commenter: Chevron Products Company

The preamble suggests that small refiners would have to voluntarily opt in to the Tier 3 program 

and comply with the 10 ppm standard to be able to generate standard credits. We note that the 

proposed regulations do not include any obvious reference to this opt-in mechanism. We are not 

able to comment on whether this opt-in would be appropriate without having the regulatory text 

available to understand how it would be implemented. 

Standard credit generation by small refiners and small volume refineries should be allowed 

during the 2017-2019 period. 
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Small refiners/refineries should be able to participate in the credit trading program. We suggest 

that the credit generation rules during the transition period, 2014 through 2019 for small 

refiners/refineries, should allow flexibility for parties to manage their credits for compliance and 

to generate value for their over-compliance. The requirement for small refiners/refineries to optin to Tier 3 to generate standard credits is not clear in the preamble and does not appear in the 

regulations. We do not understand what it would mean for a small refiner/refinery to opt-in to 

Tier 3. Could an opt-in party also opt back out? We suggest that small refiners/refineries be 

allowed to comply with the 30 ppm standard through the 2019 compliance year. Any credits 

generated during this period should be able to be used for compliance with the 30 ppm standard, 

and unused credits at the end of 2019 should be allowed to be used for Tier 3 compliance. 

Conversion of Tier 2 credits to Tier 3 credits preserves the value generated by the refinery by 

over-complying with the standard and creating a benefit for the environment. 

Commenter: Countrymark, Small Business Refiners (SBR)

We recommend that the early credit generation period be available for the three years prior to 

compliance (2014-2020) for small refiners and small volume refineries just as the early credit 

generation is available for large refineries in the three years prior to compliance. We also 

recommend that early credits are available for use three years after the compliance deadline 

(through 2023), just as they are available for large refiners. 

A small refiner that is unable to comply with the rule until 2020 will not be penalized for 

complying with the rule by the due date. Not having early credits available for use in the three 

years after equipment start-up would significantly impact a small refiner and the communities 

that they supply if issues occur (such as FCC post-treater shut down) and credits are not available 

to continue operations. 

As part of the Tier 2 regulation, EPA permitted small refiners, as well as refiners in the 

Geographic Phase-in Area, to fully participate in the ABT program at the same time the program 

started for the industry at large. This decision provided early compliance incentives for all 

refineries and maximized the credits available system-wide. EPA has not provided any 

justification on why they have significantly scaled back small volume refinery participation in 

the ABT program compared to Tier 2. 

Commenter: Countrymark

If an exemption cannot be granted, then we recommend that the ABT program be re-structured 

per our comments above to generate early credits in 2014 through 2020 and utilize early credits 

for compliance through 2023. Implementing these changes will provide appropriate relief to the 

SBRs as they implement their compliance projects. 

We prefer that the Small Business Refiners and Small Volume Refineries be exempt from 

complying with Tier 3 fuels requirements. As stated above, DOE’s estimate that small refiners 

only provide 11.9% of the gasoline supply. With this small contribution to overall emissions, we 

recommend that an exemption from the rule due to the high cost of implementation compared to 

the low impact of the required investment. EPA estimates that the 2030 sulfur reduction will be 
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14,264 tons per year; of which the estimated total contribution from fuels generated by SBR s 

will be 2,000 tons per year. 

Commenter: Small Business Refiners (SBR)

Clearly, SBRs have important financial differences from large refiners. It is a well-settled fact 

that our size limits the options we have to comply economically with new regulations. 

Small Business Refiners are important to the economy 

- Small refiners foster competition in the petroleum industry. 

- Small refiners are critical to easing the tight supply of petroleum products and often are the 

only sources of supply in their areas. 

- Most small refiners serve as the major economic resource in the small, often rural, communities 

in which they operate. 

- It is generally agreed that the economic ‘multiplier effect’ (jobs and other local and regional 

investment and businesses) resulting from refinery operations is eight-to-ten times the refinery’s 

actual budget. 

- Many small refiners provide a reliable and competitive supply of military jet fuel to our 

country’s military bases and thus are important to national security. 

Small Business Refiners Do Not Enjoy Economies of Scale 

- Large refiners are able to spread compliance and operating costs over much greater product 

sales and over a much greater asset base. 

- SBRs are not fully integrated like the large refiners. Many do not have upstream crude oil and 

gas production, midstream pipelines and terminals, or downstream retail marketing. 

- SBRs already have been at a disadvantage with major refiners relative to higher production 

costs of ultra-low sulfur and reformulated fuels on a per barrel basis. 

- SBRs as a group are most vulnerable to decreasing domestic demand for refined products and 

increased competition from renewable fuels. 

Small Business Refiners Have Limited Resources and Compliance Flexibility 

- Access to capital present much greater obstacles for SBRs than for larger refiners. 

- Small refiners do not have large staffs to negotiate and implement permitting, regulatory, and 

compliance requirements. 

- By contrast, large refiners have access to a larger qualified labor pool and can maintain large 

corporate staffs with a diverse range of specialties and in-house expertise. 

- Qualified outside engineering consulting is limited even where financial resources to procure 

such help are available. 

- Due to the smaller size of projects, SBRs are disadvantaged when competing with large refiners 

to garner outside engineering resources. 

- The majority of SBRs do not have port access like the majority of large refiners and are 

therefore more reliant upon local domestic crude supplies; they therefore have little or limited 

ability to change crude slate when regulations and specifications change. 

- The majority of SBRs are less complex than large refiners and thus have less operational 

flexibility and fewer outlets for intermediate products. 

- Small refiners owning just one or two facilities have limited internal compliance flexibility 

relative to the industry at large with respect to Average, Banking, and Trading (ABT) programs. 
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ABT programs, which are a fundamental aspect of many EPA fuel regulations, inherently 

provide more flexibility to companies owning multiple refineries than SBRs owing a single or 

few facilities. 

The Small Business Refiners would like to thank EPA for adding the definition of a Small 

Volume Refinery. This additional definition will assist many members of our Ad Hoc group that 

would not have qualified for certain benefits such as delayed implementation status under the 

small refinery definition. This change will benefit small refiners and the communities that we

supply with transportation fuels. 

While SBRs are able to achieve compliance, we will be disproportionately disadvantaged 

compared to larger facilities due to the economy of scale, scope, technical staff availability, and 

funding capabilities. Among these challenges, economy of scale to spread the capital cost over 

the barrels of produced product will be the hardest to overcome. 

We prefer that the Small Business Refiners and Small Volume Refineries be exempt from 

complying with Tier 3 fuels requirements. As stated above, DOE’s estimate that SBRs only 

provide 11.9% of the gasoline supply. With this small contribution to overall emissions, we 

recommend that an exemption from the rule due to the high cost of implementation compared to 

the low impact of the required investment. EPA estimates that the 2030 sulfur reduction will be 

17,267 tons per year; of which the estimated total contribution from fuels generated by SBRs 

will be 2,000 tons per year. 

If an exemption cannot be granted, then we recommend that the ABT program be re-structured 

per our comments above to generate early credits in 2017 through 2020 and utilize early credits 

for compliance through 2023. Implementing these changes will provide appropriate relief to the 

SBRs as they implement their compliance projects. 

The SBRs will be balancing cash flow, personnel availability, and contractor availability to 

complete implementation by 2020. Some SRBs may complete their projects in 2020 because this 

is the fastest that they are able to complete all of the project work; independent of their desire for 

early compliance and credit generation. 

Commenter: Marathon Petroleum Company LP (MPC)

Finally, since MPC believes that the average refinery size has increased since the Tier 2 

rulemaking, EPA should increase the small refinery exemption size threshold from 75 MBPD to 

90 MBPD. 

EPA should change the size limit for the small refinery exemption from 75,000 MBPD to 90,000 

MBPD

EPA should increase the “average aggregate daily crude oil throughput” amount in the “small 

volume refinery” definition from 75,000 MBPD to 90,000 MBPD to reflect changes that have 

occurred in the industry in the past several years. According to EIA, in 2000 there were 151 

refineries in the US with an average crude capacity of 111.2 MPBD. In contrast, the figures for 
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2012 were 128 refineries with an average crude capacity of 133.5 MBPD or an increase of 20%. 

In response to economic pressures, the US refining industry has shifted to a smaller pool of 

larger facilities. The concerns that the “small volume refinery” definition is intended to address 

still occur—ability to raise capital and access to engineering services—but to larger facilities. In 

recognition of that fact, EPA should increase the “small volume refinery” throughput amount 

accordingly. 

Standard credit generation by small refiners and small volume refineries should be allowed 

during the 2017-2019 period. The preamble suggests that small refiners would have to 

voluntarily opt in to the Tier 3 program. We note that the proposed regulations do not include 

any obvious reference to this opt-in mechanism. We are not able to comment on whether this 

opt-in would be appropriate without having the regulatory text available to understand how it 

would be implemented. 

If EPA implements a small refiner/refinery extension, we recommend that any small 

refiner/refinery holding Tier 2 credits at the end of 2019 should be able to convert these credits 

to Tier 3 credits. Again, these Tier 2 credits represent over-compliance with the Tier 2 standard 

and would have created a benefit for the environment. The value of these credits should not be 

lost due to expiration. Refiners should not be penalized for failing to predict their exact Tier 2 

credit requirements prior to the end of 2019. 

Commenter: Natural Resources Defense Council (NRDC)

Further, small refiners and small volume refineries have a longer period to raise needed capital 

and make investments. 

Commenter: Shell Oil Products for Shell and Motiva

EPA Should Not Exempt Small Refiners/Refineries EPA proposes to exempt both small 

refiners and small refineries until 2020. Shell disagrees and urges EPA to not pick winners and 

losers in the market place and allow all refiners and refineries to compete on a level playing 

field. 

In any event, if EPA does provide a small refinery/small refiner exemption, it should not be 

limited solely to refiners that process crude oil. As explained above regarding credit generation, 

EPA should treat the obligated parties fairly and extend this same treatment to gasoline blenders, 

which are classified as refiners under EPA’s rules, even though they do not process crude oil. 

Commenter: Private Citizen

The one issue I have is with the EPA giving a 3 year extension to refineries using less than 

75,000 barrels per day of oil to comply with the change. Many refineries of that size are usually 

owned by large oil companies that have the financial resources to implement the changes 

immediately. Giving them a 3 year extension only extends the poor health due to poor air quality 

that many residents of the USA have to contend with. 
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Commenter: United Steelworkers Union (USW)

USW supports the inclusion of methods to allow smaller refineries to seek compliance relief, and 

proposals to provide credit to refiners already producing 10ppm, which will allow for market 

trading or banking of the credits to manage compliance until 2019. Methods to ease the transition 

and allow for capital investment planning will give refiners and their workers time to adequately 

prepare facilities for the upgrades. 

Commenter: Weaver and Tidwell LLP

§80.1622(a) - Applications for small refiner or small volume refinery status must be submitted 

by March 31, 2014. Weaver recommends that this date be extended to June 30, 2014. Given the 

Agency’s aggressive time line for approval of this section, EPA will most likely not issue the 

final regulations until November 2013. Any slippage of this date would put unnecessary burden 

on the registrants. 

Commenter: Wyoming Refining Company (WRC)

These comments are prompted by the fact that WRC has not yet installed its Tier 2 compliance 

equipment, but, instead, has been demonstrating compliance with Tier 2 sulfur credits generated 

under the small refiner provisions of the Tier 2 rule. Under the proposed Tier 3 rule, WRC would 

be allowed to purchase and use Tier 2 credits through 2019 rather than construct either a Tier 2 

or Tier 3 project now and, therefore, forfeit the intended small entity benefits of the proposed 

Tier 3 rule.

WRC, therefore, respectfully suggests that the final rule contain two additional provisions. First, 

any Tier 2 or early Tier 3 sulfur credit may be used by a small refiner or small volume refinery 

for compliance with Tier 2 requirements through 2019. Second, the life of any 2013 and earlier 

Tier 2 credits shall be extended through 2019 so long as they are owned by a small refinery or 

small volume refinery. These provisions will broaden the supply of credits available for small 

refiner and small volume refinery Tier 2 compliance through 2019. There may be concerns about 

small volume refineries owned by multi-refinery companies and the ability to shift credits from 

one facility to another. WRC, however, feels these concerns are not valid since, beginning in 

2017, the only demand for Tier 2 credits will be from small refiners and small volume refineries. 

Tier 2 credits will have no further value for larger refineries and will necessarily be obtained 

only for small facility compliance. 

Our Response:

Small Refiner/Small Refinery Delay

As discussed in Section XII.C of the preamble to the final rule, refiners who are classified 

as small businesses (“small refiners”) as a category generally lack the resources that are available 

to larger companies to raise capital for investing in a new regulatory program, such as shifting of 

internal funds, securing of financing, or selling of assets. As noted by comments above, and 

based on information available from small refiners and others, we believe that the category of 
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entities classified as small generally face unique circumstances with regard to compliance with 

environmental programs, compared to larger entities. As such, the final Tier 3 gasoline sulfur 

program includes provisions that will provide assistance for small businesses in meeting the 10 

ppm average sulfur standard. This approach will allow the overall program to begin as early as 

possible; achieving the air quality benefits of the program as soon as possible, while helping to 

ensure that small businesses have adequate time to raise capital for new fuel desulfurization 

equipment or to make any other needed changes. We also believe that small business regulatory 

flexibilities can provide these entities with additional help and/or time to accumulate capital 

internally or to secure capital financing from lenders, and could spread out the availability of any 

needed engineering and construction resources in a manner that they are available by the time 

they are needed.

As discussed in Sections V and XII.C of the preamble to the final rule, we are also aware

that there are some refineries that may experience higher compliance costs on a per-gallon basis 

than other refineries, and in some cases considerably higher. In many cases, these are refineries 

owned by a refiner/company that would not meet the Small Business Administration definition 

of a small business (as those entities classified as “small refiners” do). In many cases, these 

small refineries compete directly in markets also supplied by small business refineries. In an 

oversupplied gasoline market, these refineries may have difficulty justifying capital investments 

to comply with new standards. Overall, we believe that these refineries are disproportionally 

impacted when it comes to their cost of compliance and ability to rationalize the investment costs 

in today’s gasoline market. These small refineries also find it more difficult to obtain vendor, 

contractor, and engineering firm support, as these firms find it more profitable to first focus on 

the larger refinery projects. Giving these refineries additional lead time will allow more time to 

invest in desulfurization technology, take advantage of advancements in technology, develop 

confidence in a Tier 3 credit market as a means of compliance, and avoid competition for capital, 

engineering, and construction resources with the larger refineries.

While the small business refiners as a category, and the small volume refineries as a 

category are expected to experience a greater challenge in complying with Tier 3 than larger 

refiners/refineries, within these categories are also refineries that are already complying with the 

Tier 3 sulfur standards or need take little action to comply with Tier 3. Consequently, providing 

a delay in compliance to these categories of refineries as a whole must be balanced against 

providing an unnecessary delay in compliance and/or a windfall in credit generation. To avoid 

windfall credits for those refineries that are already complying with the Tier 3 standard, we have 

also carefully constructed the program such that they generate credits relative to 30 ppm prior to 

2017 like all other refineries and relative to 10 ppm beginning in 2017 just like all other 

refineries for use in complying with Tier 3. Furthermore, we do not believe that refineries that 

do not process crude oil (e.g., produce gasoline from blendstocks) experience the same challenge 

in complying with Tier 3, and thus do not warrant such relief. They have the ability to comply 

through low or even no capital cost changes relatively quickly and easily in comparison to the 

FCC naptha hydrotreating modifications required by many refineries that produce gasoline by 

processing crude oil. 

We do not believe a complete exemption from the program is appropriate, as this could 

create situations where vehicles could receive fuel that is above a 10 ppm average sulfur 
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standard. However, we do believe a short amount of additional lead time for these refiners and 

refineries will provide them needed assistance with compliance while still allowing the Tier 3 

program to begin on January 1, 2017. Thus, the final Tier 3 program includes a delayed 

compliance schedule for small refiners and small volume refineries of January 1, 2020 for small 

refiners, which will allow these entities to postpone compliance with the Tier 3 program for up to 

three years. Small refiners and small volume refineries will have from January 1, 2017 through 

December 31, 2019 to continue production of gasoline with an average sulfur level of 30 ppm 

(per the Tier 2 gasoline sulfur program). This delayed compliance schedule is not intended as an 

opportunity for these refiners and refineries to increase their production of gasoline with sulfur 

levels greater than 10 ppm, but rather will help small refiners/small volume refineries with 

compliance with the Tier 3 program. Compliance with the 10 ppm annual average sulfur 

standard will begin on January 1, 2020, thus small refiners and small volume refineries may 

continue using Tier 2 gasoline sulfur credits through December 31, 2019 to meet their refinery 

average 30 ppm sulfur standard. Refiners must apply, and be approved, for small refiner or 

small volume refinery status. Applications are due on January 1, 2015.

Small Volume Refinery Definition

We disagree with comments that suggested we increase the size threshold for small 

volume refineries. As noted above, we are aware that some refineries that may experience higher 

compliance costs than other refineries and that these refineries are owned by a refiner/company 

that would not meet the definition of a small business. In recognition of this concern under the 

RFS program, Congress granted all refineries with a crude oil throughput of less than or equal to 

75,000 barrels per calendar day (bpcd) additional time to comply. The Tier 3 final rule includes a 

small volume refinery net crude throughput of less than or equal to 75,000 bpcd, based on the 

highest crude throughput for the 2012 calendar year. In analyzing various crude throughput 

maximums between 75,000 and 90,000 bpcd, as suggested by a commenter, we do not believe it 

is appropriate or necessary to increase the threshold beyond what was previously set by 

Congress. The 75,000 bpcd limit set by Congress was to recognize those refineries that would 

have difficulty with compliance with a rulemaking (from both a cost and feasibility standpoint), 

raising this limit would go beyond Congress’ intent.

Nor do we believe it is necessary or appropriate to extend this definition to include 

refineries that produce gasoline only from purchased blendstocks. The purpose of the relief is to 

allow lead time for capital investments for refineries that are producing gasoline from crude oil. 

Refineries using blendstocks can control their sulfur levels through their blendstock purchases. 

Furthermore, allowing this could open a significant compliance loophole that would be difficult 

if not impossible to enforce. 

ABT for Small Refiners and Small Refineries

We are also finalizing provisions that would allow approved small refiners and small 

volume refineries to generate credits for overcompliance with the 30 ppm Tier 2 standard prior to 

January 1, 2020. Such credits generated by small refiners and small volume refineries can be 

traded/sold to non-small refiners for use by December 31, 2019, and the credit revenues could be

used to help offset their Tier 3 investments. When the Tier 3 program begins on January 1, 
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2017, small refiners and small volume refineries may continue to generate credits for 

overcompliance with the 30 ppm sulfur standard (as they will still be subject to the Tier 2 

standards through December 1, 2019), or they may generate credits for overcompliance with the 

Tier 3 10 ppm sulfur standard. Any credits generated for sulfur levels below 10 ppm will be 

eligible for compliance with either the Tier 2 or Tier 3 programs. Any credits generated for 

sulfur levels above 10 ppm (and below 30 ppm) will only be eligible for use in complying with 

the Tier 2 standards from 2017-2019. For example, in 2017, a small refiner with an annual 

gasoline sulfur average of 8 ppm could generate 20 ppm-volume Tier 2 credits (30 ppm-10 ppm) 

that could be used by other small refiners and small volume refineries, or banked by the refinery 

for future Tier 2 compliance. This small refiner would also generate 2 ppm-volume Tier 3 

credits (10 ppm-8 ppm) that could be sold to refiners and importers subject to Tier 3, or banked 

by the refiner for future Tier 3 compliance. In response to comments, under the final program 

there is no longer any need for designation of credits for Tier 2 or Tier 3. The designation occurs 

automatically based on the sulfur level. Further, small refiners and small volume refineries will 

not be required to “opt-in” to the Tier 3 ABT program.

As discussed above, all credits generated prior to January 1, 2017 will be valid for use for 

five years or through December 31, 2019, whichever is earlier. There is a five year statute of 

limitations on recordkeeping, and credit life is tied to this limit. Allowing credits to be valid for 

longer than five years would violate this statute of limitations. While a previous EPA fuels 

program has allowed for a small business flexibility that would allow for credits to be sold to and 

used by small refiners only, in no case do these provisions allow for credit life beyond five years. 

Further, the January 1, 2020 compliance date for small refiners and small volume refineries is 

also the date on which no credits generated relative to 30 ppm may be used for compliance. The 

result is that all refiners and importers will be in compliance with the 10 ppm annual average 

sulfur standard, whether by producing gasoline with an average sulfur level of 10 ppm or using 

credits that were generated against a 10 ppm sulfur standard.

5.5.4 Other

What Commenters Said:

Commenter: Private Citizens

And finally, I was wondering – I guess the ABT speaks to that – will the refineries get credits of 

some sort for alternatives, or will there be some sort of a bonus or subsidy provided so that if an 

alternative, say, from an algae or greenfield comes along, it could be dropped in, and there could 

be an exchange of some sort.

Our Response:

With regard to the comment regarding credits or bonuses/subsidies for alternatives, this is 

not part of the Tier 3 ABT program. The flexibility afforded by the ABT program allows for the 

generation of credits relative to gasoline sulfur reduction, and these credits can then be used, or 

traded to another refiner, for compliance with the average gasoline sulfur standard. Allowing for 
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credits for other alternatives would not necessarily meet the gasoline sulfur reduction goals of the 

Tier 3 program. 

5.6. Compliance Provisions (Registration, Reporting, Recordkeeping, Exemptions)

5.6.1 Downstream Added Oxygenate

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

API and AFPM do not support EPA’s proposal within new §80.1603(d)(3) that anyone adding 

oxygenate downstream from a refinery or import facility to assume the sulfur content to be 10.00 

ppm. API and AFPM recommend modifying the proposed rule to allow the downstream blender 

of DFE into conventional gasoline to either use the actual commercial ethanol sulfur value or 

allow laboratory hand blends, as similarly provided for RBOB/RFG in §80.69(a). 

Commenter: Marathon Petroleum Company LP (MPC)

MPC does not support EPA’s proposal within new §80.1603(d)(3) that anyone adding oxygenate 

downstream from a refinery or import facility to assume the sulfur content to be 10.00 ppm. This 

requirement would preclude a conventional gasoline producer adding downstream DFE from 

using the actual low sulfur level but an artificial (high) value. MPC recommends modifying the 

proposed rule to allow the downstream blender of DFE into conventional gasoline to either use 

the actual commercial ethanol sulfur value or allow laboratory hand blends, as similarly provided 

for RBOB/RFG in §80.69(a). 

Commenter: Countrymark, Small Business Refiners (SBRs)

EPA states that oxygenates added downstream of the refinery may be included in the sulfur 

calculation. Where oxygenate added downstream from the refinery or import facility, an assumed 

10.00 ppm sulfur content must be used. 

We believe that this language should be modified to increase blending flexibility and encourage 

additional ethanol blending, up to a 10% limit. We recommend that parties blending gasoline and 

oxygenates without a Certificate of Analysis (COA) for oxygenates should assume that the sulfur 

content is 10.00 ppm. Any oxygenate that is blended with gasoline with a COA demonstrating 

that the sulfur content is less than 10.00 ppm may apply that sulfur-volume to the overall blend 

calculations. 

This additional flexibility in blending will provide gasoline blending options and/or increase the 

possible sulfur credits that are available to meet compliance requirements. Credit generation 

should be permitted only for the obligated party as defined in the rule. This is important to the 
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CountryMark because we own and operate the refining and terminal assets. This flexibility 

provides a tangible relief and real options to u s as we own and operate facilities and are the 

obligated party. 

Increasing our flexibility in blending low sulfur oxygenate blend components into our fuels 

enables us to deliver lower cost fuels to our communities. Including the oxygenate sulfur content 

in our final blend calculations will enable u s to reduce our operating costs in the refinery to 

offset some of the expected $250,000+ per year increase that we are anticipating as a result of 

this new rule. 

Our Response:

In demonstrating compliance with the gasoline sulfur standards finalized under the Tier 3 

program, gasoline refiners and importers may adjust the sulfur levels in the gasoline and 

blendstocks for oxygenate blending (BOBs) that they produce/import to account for the 

downstream addition of ethanol. We proposed that the sulfur content of denatured fuel ethanol 

(DFE) used for downstream blending would be assumed to be 10 ppm in making such 

demonstrations of compliance. We agree with the comments that refiners and importers should 

be allowed to use the actual sulfur content of DFE when a sulfur test result is available and when 

the refiner can demonstrate that the test result was derived from a representative sample of the 

DFE that was blended with the gasoline or BOB. We also agree that the sulfur content of in-use 

DFE will typically be lower than the Tier 3 program’s 10 ppm sulfur cap for DFE. We assumed 

that DFE would have an average sulfur content of 5 ppm in conducting the refinery analysis to 

support the Tier 3 final rule. Therefore, the Tier 3 program requires that in determining their 

compliance with today’s sulfur standards, refiners and importers must either use the actual sulfur 

content of the DFE established through testing of the DFE actually blended or assume a 5 ppm 

sulfur content for the DFE added downstream. To prevent potential bias, a refiner or importer 

must choose to use only one method during each annual compliance period.

5.6.2 Registration, Recordkeeping, and Reporting Requirements

5.6.2.1 Registration

What Commenters Said:

Commenter: Shell Oil Products for Shell and Motiva

There is an inconsistency between the preamble, 78 Fed. Reg. 29942, and the proposed 

regulations in 40 CFR 80.1650 pertaining to registration. In the proposed registration regulations 

in 40 CFR 80.1650 (a)(1), we recommend that the phrase “unless already registered under 80.76 

or 80.103” be added so that new registrations are not required. Similarly, for 40 CFR 80.1650 (a) 

(3), we recommend that the phrase “unless already registered under 80.76” be added so that new 

registrations are not required. These changes would be consistent with the preamble on page 311 

– “Most refiners, importers, and ethanol producers are currently registered with EPA under other 
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40 CFR part 80 fuels programs. We are proposing that those who are already registered would 

not have to register again.”. 

Our Response:

Regarding the comments that suggested an inconsistency between the preamble and 

regulations for reporting, we agree with the comments and have changed the regulatory language 

accordingly.

5.6.2.2 Reporting

What Commenters Said:

Commenter: Countrymark; Small Business Refiners (SBRs)

Sections 80.1652 and 80.1653 establish reporting and recordkeeping requirements. We believe 

that the small refiner’s exemption should apply to this section. Small refiners and small volume 

refineries should begin reporting and recordkeeping when credit generation begins or by the 

compliance deadline of 2020, whichever is earlier. Requiring small refiners to meet this section 

of the rule prior to project implementation adds value for neither EPA nor small refiners. 

Our Response:

Since the Tier 2 program essentially transitions into the Tier 3 program, all regulated 

entities under the Tier 3 program will continue to be subject to the reporting provisions and all 

other compliance requirements (e.g., recordkeeping) of the Tier 2 program until they begin 

participating in the Tier 3 program. As stated in the regulations at §80.1602, the requirements of 

the Tier 3 program (40 CFR part 80 subpart O) apply beginning January 1, 2017 except in the 

case of credit generation prior to 2017 and the small refiner/small volume refinery delay; the 

requirements of the Tier 2 program (40 CFR part 80 subpart H) continue to apply until that point.

5.6.2.3 Recordkeeping Requirements

What Commenters Said:

Commenter: Consumer Specialty Products Association (CSPA) & Automotive Specialty 

Products Alliance (ASPA)

The maximum treatment rate is currently stated on the product transfer document or the 

packaging for aftermarket additives. Further, it will not be overly burdensome for aftermarket 

additive manufacturers to maintain records of their additive production quality control activities, 

demonstrating that the sulfur content of additive production batches complies with the proposed 
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sulfur requirement. Our members are committed to making five years of these reports available 

to EPA upon request. 

Commenter: Countrymark

Sections 80.1652 and 80.1653 establish reporting and recordkeeping requirements. We believe 

that the small refiner’s exemption should apply to this section. Small refiners and small volume 

refineries should begin reporting and recordkeeping when credit generation begins or by the 

compliance deadline of 2020, whichever is earlier. Requiring small refiners to meet this section 

of the rule prior to project implementation adds value for neither EPA nor small refiners. 

Section 80.1653(g) requires all of the records collected to be made available to EPA upon 

request 

We strongly oppose collecting and maintaining the names and titles of employees collecting 

samples and the names of employees performing laboratory analysis. We believe in protecting 

the privacy of our employees and enabling them to perform their job without fear that their 

personal information will be released directly to the public or indirectly to the press through a 

Freedom of Information request. In May and June 2013, several news outlets covered the release 

of farmers’ personal information by EPA. 

We appreciate EPA’s desire for individual accountability at our facilities. If we cannot eliminate 

the need to collect employee names and positions, we request that EPA not take custody of this 

information upon data inspections. We request that this information remain at our facilities 

where we will maintain control of the personal information. Finally, if EPA does require 

possession of this data, we request that our employees information be protected under the 

Privacy Act and not be released to the public. 

While examining recordkeeping requirements in section 80.1653, we notice that the 

recordkeeping requirements for denatured ethanol and other oxygenates and the recordkeeping 

requirements for fuel producers are significantly different. The recordkeeping requirements 

imposed on importers and parties that produce, import, sell, offer for sale, dispense, distribute, 

transport gasoline, refine crude oil into finished products are more than double those which 

oxygenate producers are required to produce. 

We believe that the records requirements for both parties should be equivalent. We recommend 

that the recordkeeping burden be reduced as follows for Fuel Producers: eliminate name and title 

of person collecting sample and eliminate name of the tester. We further recommend that 

oxygenate producers collect the following information, as it is valuable information in 

maintaining fuel quality and tractability: Location, Time, Storage tank/truck identification, other 

testing results, test methodology used, oxygenate batch number, and ethanol production date. 

The table below [of EPA-HQ-OAR-2011-0135-4781-A2] illustrates the differences between the 

two parties. 
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Commenter: Small Business Refiners (SBR)

Section 80.1652 and 80.1653 establishes reporting and recordkeeping requirements. We believe 

that the exemption for small refiners and small volume refineries should apply to this section. 

Small refiners and small volume refineries should begin reporting and recordkeeping when credit 

generation begins or by the compliance deadline of 2020, whichever is earlier. Requiring SBRs 

to meet this section of the rule prior to project implementation adds value for neither EPA nor 

SBRs. 

Section 80.1653(g) requires all of the records collected to be made available to EPA upon 

request. 

We strongly oppose collecting and maintaining the names and titles of employees collecting 

samples and the names of employees performing laboratory analysis. We believe in protecting 

the privacy of our employees and enabling them to perform their job without fear that their 

personal information will be released directly to the public or indirectly to the press through a 

Freedom of Information request. In May and June 2013, several news outlets covered the release 

of farmers’ personal information by EPA. 

We appreciate EPA’s desire for individual accountability at our facilities. If we cannot eliminate 

the need to collect employee names and positions, we request that EPA not take custody of this 

information upon data inspections. We request that this information remain at our facilities 

where we will maintain control of the personal information. Finally, if EPA does require 

possession of this data, we request that our employees information be protected under the 

Privacy Act and not be released to the public. 

While examining recordkeeping requirements in section 80.1653, we notice that the 

recordkeeping requirements for denatured ethanol and other oxygenates and the recordkeeping 

requirements for fuel producers are significantly different. The recordkeeping requirements 

imposed on importers and parties that produce, import, sell, offer for sale, dispense, distribute, 

transport gasoline, refine crude oil into finished products are more than double those which 

oxygenate producers are required to produce. 

We believe that the records requirements for both parties should be equivalent. We recommend 

that the recordkeeping burden be reduced as follows for Fuel Producers: eliminate name and title 

of person collecting sample and eliminate name of the tester. We further recommend that 

oxygenate producers collect the following information as it is valuable information in 

maintaining fuel quality and tractability: Location, Time, Storage tank/truck identification, other 

testing results, test methodology used, oxygenate batch number, and ethanol production date. 

The table [of EPA-HQ-OAR-2011-0135-4804-A2] below illustrates the differences between the 

two parties. 

Our Response:
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Regarding product transfer documents and recordkeeping for aftermarket additives, the 

Tier 3 program finalized the requirement that manufacturers of gasoline additives used 

downstream of the refinery at less than 1 volume percent must limit the sulfur contribution to the 

finished gasoline from the use of their additive to no more than 3 ppm when the additive is used 

at the maximum recommended treatment rate. The additive manufacturer will be required to 

maintain records of its additive production quality control activities which demonstrate that the 

sulfur content of additive production batches is such that when the additive is used at its 

maximum recommended treatment rate it will add no more than 3 ppm to sulfur content of the 

finished gasoline. The additive manufacturer will also be required to list the maximum 

recommended treatment rate on the product transfer document. Records will be required to be 

maintained for 5 years by additive manufacturers and made available to EPA upon request. We 

agree with the comments that these requirements will not impose a substantial burden on 

gasoline additive manufacturers.

As discussed above in Chapter 5.6.2.2, all regulated entities under the Tier 3 program will 

continue to be subject to the compliance provisions (such as reporting and recordkeeping) of the 

Tier 2 program until they begin participating in the Tier 3 program. As stated in the regulations 

at §80.1602, the requirements of the Tier 3 program (40 CFR part 80 subpart O) apply beginning 

January 1, 2017 except in the case of credit generation prior to 2017 and the small refiner/small 

volume refinery delay; the requirements of the Tier 2 program (40 CFR part 80 subpart H) 

continue to apply until that point.

Regarding the comments about concerns about employee privacy in recordkeeping, we 

do understand the commenters’ concerns. However, in the case of an inspection or enforcement 

action, it is important for EPA’s enforcement personnel to know who did the actual sampling and 

testing in the event that questions arise. We will work to ensure the privacy of individuals whose 

names appear in those records, and that they will not be released publicly.

We agree with the comments that enforcement and compliance assurance would be 

substantially improved by requiring oxygenate producers/importers and denaturant 

producers/importers to maintain records regarding the location, time, storage vessel 

identification, other test results, test methodology used, oxygenate batch number, and oxygenate 

production date. Hence, the Tier 3 FRM finalizes requirements to this effect.

5.6.2.4 Sampling and Testing Requirements

What Commenters Said:

Commenter: Flint Hills Resources, LP (FHR)

Individual Batch Reporting of Gasoline and Other Fuels Should Not Be Required 

FHR believes that reporting of each batch of gasoline under §80.1652 has little value, and EPA 

should not consider individual batch reporting for DFE producers. FHR agrees that batch records 

should continue to be part of the recordkeeping requirements within §80.1653, but only 
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aggregated reports be submitted to EPA. Similar to how the diesel sulfur program is currently 

structured, fuel producers should be required to keep batch records that demonstrate compliance 

with standards and support annual reporting. Individual batch records would be made readily 

available to EPA upon request or during inspections.

Our Response:

Chapter 5.3 of this Response to Comments document contains comments regarding the 

reporting requirements for oxygenate producers. As discussed in Chapter 5.3, we continue to 

believe that annual reports from oxygenate producers are an important enforcement and 

compliance assurance tool. Therefore, the Tier 3 FRM finalized the requirement that producers 

and importers of DFE and other oxygenates must submit annual reports to EPA that include the 

total volume of DFE/oxygenate produced and an attestation that all batches met fuel quality 

requirements.

It is also important for EPA’s enforcement personnel to know who did the actual 

sampling and testing in the event that questions arise in the case of an inspection or enforcement 

action concerning gasoline, oxygenates, and certified ethanol denaturant. Therefore, the Tier 3 

final rule requires that records be maintained by gasoline producers/importers, oxygenate 

producers/importers, and certified denaturant producers/importers regarding the name and title of 

the person who performs the required sampling and testing. 

5.6.3 Sampling and Testing

What Commenters Said:

Commenter: Countrymark; Small Business Refiners (SBRs)

Sections 80.1630 and 80.1631 state that refiners and importers will collect, test, and retain 

samples from each batch of gasoline that is produced or imported; using the sample and testing 

methodology provided in the rule. We believe that the small refiner’s exemption should apply to 

this section. Small refiners and small volume refineries should begin collecting, testing, and 

retaining samples when credit generation begins or by the compliance deadline of 2020, 

whichever is earlier. Requiring small refiners to meet this section of the rule prior to project 

implementation adds value for neither EPA nor small refiners and will produce data not 

reflecting an operator’s post-implementation product. 

Our Response:

As discussed in Chapter 5.6.2, above, Tier 2 compliance requirements for small refiners 

and small volume refineries, such as sampling and testing, will apply until participation in the 

Tier 3 program begins.

5.6.4 National Security Exemptions
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What Commenters Said:

Commenter: Department of Defense Clean Air Act Services Steering Committee

Our enclosed comment supports EPA’s proposed inclusion of a national security exemption for 

gasoline used in tactical equipment and other military vehicles and equipment covered by a 

National Security Exemption. 

The Department of Defense (DoD) supports the inclusion by the Environmental Protection 

Agency (EPA) of a national security exemption (NSE) for gasoline used in tactical and other 

NSE-covered military equipment. NSEs are necessary for DoD until such time that low sulfur 

fuels are available worldwide. 

Due to national security considerations, EPA’s existing regulations provide either explicit NSEs 

to the military or allow the military or manufacturers to request and receive NSEs from 

emissions regulations for DoD motor vehicles, engines and equipment if the operational 

requirements for such vehicles, engines, or equipment warrant such an exemption. 

In order to prevent adverse interaction with after-treatment devices required by EPA regulations 

in compliant engines, EPA also established fuel sulfur standards that apply to all fuels used in 

regulated vehicles and equipment. The availability of these low or ultra-low sulfur fuels in all 

locations and scenarios where DoD operates for national security purposes cannot be guaranteed. 

Therefore, EPA regulations for fuels also include NSE language, but only if the fuels are used in 

tactical military vehicles, engines, or equipment that are covered by a national security 

exemption. 

EPA stated in the final 2007 Non-Road, Locomotive and Marine (NRLM) diesel fuel regulation 

(69 Fed. Reg. 38958, June 29, 2004), that providing an exemption for military diesel fuel used in 

tactical, non-road engines and equipment will not have any significant environmental impact. 

This conclusion was based on data provided by DoD for implementing a similar exemption 

provision in the highway diesel program. Also, EPA and DoD have developed, and effectively 

used for many years, a process to address and obtain NSE for the tactical vehicles, engines, and 

equipment covered by fuel exemptions on a case-by-case basis, when required. We believe, as 

EPA indicated in final NRLM diesel fuel regulation, that the NSE provides DoD with the needed 

flexibility to meet its goals of keeping vehicles, engines, and equipment ready for quick 

deployment overseas. We further believe that the exemptions are still needed by DoD to fulfill its 

mission on a worldwide basis, to respond adequately and quickly even if emerging economic or 

geopolitical situations will not allow the availability of either low or ultra-low sulfur fuels 

required for the proper operation of compliant engines. 

Though gasoline use is not as common in military tactical vehicles and equipment as diesel, the 

same requirements for worldwide deployability exist. Currently, only Europe and a few isolated 

countries have regulations in place which meet the proposed 10 part per million (ppm) gasoline 

standard. Many parts of the world will not have the new 10 ppm sulfur gasoline available that 

will be required for Tier 3 gasoline engines, with a majority of countries producing 100-2,500 
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ppm sulfur gasoline. DoD expects that it may require NSE from the Tier 3 standards for some 

gasoline engines and equipment that are used overseas. At the same time, the fuel NSE proposed 

in this rule will cover any gasoline purchased overseas and remaining in the fuel tanks of the 

equipment when returned to the United States. In addition, DoD has previously and continues to 

procure fuel for long term storage in Maritime Prepositioning Ships. The fuel procured for this 

purpose may also return to the United States in equipment in which it was used. The sulfur 

content of the fuel currently in storage exceeds the proposed limits. Also, in DoD’s role in 

support of disaster relief activities, often times higher sulfur fuel is procured to ensure a quick 

and efficient supply of fuel which meets the demand of these activities. 

For example, DoD purchases modified commercial vehicles for our special operations forces 

which may not meet EPA Tier 3 emissions standards or may be designed to operate on gasoline 

that does not meet the Tier 3 standards. These vehicles are required so that our special operations 

forces have the capability to conduct missions where there is no military logistical presence and 

where vehicles must be maintained on the local economy. 

In the case of our tactical vehicles, even if compliant fuels are available world-wide, there are 

cases where in-engine and after-treatment controls are incompatible with military operational 

requirements. For example, engine structural improvements allowing for higher pressure 

combustion, electronic engine and after-treatment controls, and the after-treatment systems 

themselves often do not meet military shock, vibration, electro-magnetic interference, reliability, 

and maintainability requirements necessary for operation in a combat environment. 

Failure or performance degradation of an engine in combat can have unacceptable dire 

consequences such as personnel casualties or military mission failure. Therefore, DoD will 

continue to need access to NSE for both engines and fuels included in this rule and other mobile 

source regulations for the foreseeable future. 

EPA should include the provision that exempts gasoline produced, imported, sold, offered for 

sale, supplied, offered for supply, stored, dispensed or transported for use in tactical military 

vehicles, engines, or equipment as proposed. 

Our Response:

In both our diesel fuel and Tier 2 gasoline sulfur programs, we provided an exemption for 

fuel used in tactical military vehicles and nonroad engines and equipment with a national 

security exemption (NSE) from the vehicle and engine emissions standards. Due to national 

security considerations, some of our existing regulations allow the military to request and receive 

NSEs for vehicles, engines, and equipment from emissions regulations if the operational 

requirements for such vehicles, engines, or equipment warrant such an exemption. Fuel used in 

these applications is also exempt if it is used in tactical military vehicles, engines, or equipment 

that are not covered by an NSE but, for national security reasons (such as the need to be ready 

for immediate deployment overseas), need to be fueled on the same fuel as those with an NSE. 

This exemption is being continued in the Tier 3 gasoline program as well.
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5.7. Other, including Alternatives

5.7.1. Butane Standard

What Commenters Said:

Commenter: Mid-Continental Energy (MCE)

EPA is proposing to reduce the sulfur content to 10ppm in butane blended into gasoline by 

terminal blenders. MCE supports this change with the request that butane blenders be allowed to 

use averaging on a monthly basis to meet the 10ppm. There are several streams of butane that 

have an average sulfur content of 15ppm to 20ppm. For example, a butane blender should be 

allowed to purchase some streams with 15ppm during the month if the average butane blended 

during the month calculates at 10ppm. This extra flexibility would be a benefit to potential 

butane blenders whose supply of butane with 10ppm sulfur could be limited. 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

In the Preamble, EPA described the current butane blending rules and proposed to lower the 

sulfur standards that are now applicable to butane to a 10 ppm cap – consistent with the Tier 3 

proposed standard for the annual average gasoline. Members of the Association are concerned 

that this reduced sulfur level would inhibit butane blending due to the reduced availability of 

butane with very low sulfur. The regulated community needs more flexibility because it is 

usually difficult and costly to find butane with a sulfur content of 10 ppm or below. Therefore, 

instead, EPA should consider focusing on the sulfur content of the final blend – not the butane 

component. Blenders downstream of the refiner/import gate should be permitted to add butane 

that meets the downstream per-gallon cap so long as the butane blending operation does not 

cause the blender’s finished gasoline to have an annual average sulfur content above 10 ppm.

Recommendation: The Association recommends that EPA continue to provide flexibility to 

butane blending and consider a requirement that butane only need meet the downstream pergallon sulfur cap so long as the butane blending operation does not cause the annual average 

sulfur content of the gasoline to exceed the proposed Tier 3 standard of 10 ppm. Moreover, the 

Association supports broadening the butane blending provisions to include pentane.

Provide greater flexibility for butane blending and expand butane blending provisions to include 

pentane.

Our Response:

As discussed in Section V.I. of the preamble to today’s final rule, under the Tier 2 

gasoline program, “purity” butane blended into gasoline downstream of the refinery is subject to 

a 30 ppm sulfur cap and other specifications regarding its composition.15 This is consistent with 

the 30 ppm refinery average sulfur standard under the Tier 2 program. The Tier 3 FRM finalized 

 

15 40 CFR 80.82.
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the proposed 10 ppm sulfur cap for purity butane blended into gasoline effective January 1, 

2017. This is consistent with the Tier 3 10 ppm refinery average sulfur specification.

Butane and has an inherently low sulfur content that can be made to meet a 10 ppm sulfur 

cap with relatively mild desulfurization techniques. We anticipate that butane suppliers will 

desulfurize these blendstocks to well below 10 ppm sulfur as part of their response to the Tier 3 

gasoline sulfur requirements. There is no need to allow higher sulfur levels for butane blended 

voluntarily downstream that would result in higher gasoline sulfur levels. Furthermore, allowing 

butane used for RVP trimming to exceed a 10 ppm sulfur cap would needlessly complicate 

compliance assurance.

5.7.2. CNG/LPG In-Use Fuel Standards

What Commenters Said:

Commenter: Advanced Biofuels USA (ABFUSA)

Consideration of CNG and LPG Emissions Test Fuel: In the past sulfur content regulation of 

“natural gas” sources fuels was not seen as necessary for two reasons, 1) the low volume of use, 

and 2) the historically low sulfur content of US “conventional” natural gas sources. However, 

with “unconventional” (fracked) natural gas sources now providing over 60% of the US NG 

supply (US DOE/EIA 2012 data) sulfur content becomes an issue because of the higher content 

in the unconventional gas. Therefore, EPA should enact standards for sulfur content of NG and 

LNG transport fuels that are equal (in terms of pollutant/mile) of these proposed Tier 3 

regulations. 

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

...but emphasize that EPA should ensure that all market fuels, including LPG and CNG meet the 

same “total” sulfur standards as Tier 3 gasoline.

If market CNG or LPG do not meet the proposed Tier 3 emissions certification fuel standards, 

then there must be relief in the emissions standards to accommodate potential deterioration in 

vehicle emissions systems capability resulting from the use of higher sulfur fuels. The 

Coordinating Research Council Performance Committee is in the process of conducting a 10 

U.S. city fuel survey on retail CNG. Two samples will be collected from each city and results are 

expected during the 4th quarter of 2013. CNG and LPG fuels are not subject to the same degree 

of regional refinery differences as conventional liquid fuels. However, there can be large 

differences in marketplace gaseous fuel quality as a result of: (1)the amount of processing they 

receive as a result of their source, i.e., well-head gas versus refinery gas; (2)the type of 

dehydration and filtering they receive just prior to or directly at retail dispensers. 
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U.S. CNG and LPG industries are at the front end of what appears to be the start of a long term 

growth trend, so it is an appropriate time to establish market and test fuel standards, including for 

sulfur.

Commenter: American Gas Association (AGA)

The American Gas Association appreciates that as natural gas increasingly moves into the 

mainstream as a motor vehicle fuel, the industry will need to work closely with the EPA to 

ensure a smooth transition. Natural gas is an emerging motor vehicle fuel that we believe offers 

tremendous societal benefits, including aiding in the transition to hydrogen fuel cell vehicles. If 

the agency elects to develop sulfur standards for CNG, we urge the agency to work with the 

natural gas industry to adopt a phased-in approach. Such an approach would allow the industry 

time to assess the current state of natural gas fuel quality with respect to sulfur, and to adopt any 

remediation practices that may prove to be required. Conversely, we fear an overly aggressive 

timeline toward regulation would stymie the adoption of an alternative fuel that offers the 

promise of significant benefits to our nation. 

As noted by EPA in the proposed rule, there are currently no sulfur standards for the fuel used in 

compressed natural gas (CNG). EPA has requested comment on whether it is necessary for EPA 

to establish sulfur standards for CNG, and whether a 15 ppm sulfur cap similar to that 

established for highway Diesel fuel would be appropriate. EPA further requested comment on 

whether and how to address the sulfur contribution from odorants and other additives used in 

CNG. 

The American Gas Association believes that, to the extent possible, standards for motor vehicle 

fuel should be fuel neutral. AGA appreciates the importance of regulating sulfur content in 

motor vehicle fuels, due to the potential damage that high levels of sulfur content in motor 

vehicle fuels can impose on the exhaust after-treatment systems on-board vehicles. Natural gas 

is an inherently cleaner burning fuel than gasoline or diesel, and dedicated natural gas vehicles 

do not require the same exhaust after-treatment systems required for gasoline and diesel vehicles 

to meet EPA standards for emissions of criteria pollutants. Natural gas sulfur content, when used 

for dedicated-use NGVs, is unlikely to be a significant issue. 

However, the American Gas Association believes that dual-fuel vehicles – capable of running on 

either gasoline or CNG, or potentially diesel and CNG – will be an important market component 

as natural gas vehicles gain acceptance as a mainstream motor fuel. AGA recognizes that the 

sulfur content of natural gas could impact the efficacy of exhaust after-treatment systems 

designed to alternate between CNG and petroleum-based fuels. In other words, the sulfur 

content of CNG, when used for dual-fuel vehicles, could have negative impacts on the emissions 

of these vehicles while operating in a conventional fuel mode. 

NGVs provide a number of social benefits, including reductions in some cases in emissions of 

nitrogen oxides and particulate matter, as compared to gasoline or diesel vehicles. The greater 

use of natural gas as a transportation fuel also offers additional societal benefits, including 

strengthening our national energy security, and improving our balance of trade, by displacing 

imports of foreign petroleum and insulating our economy from the comparative volatility of oil 
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prices vis-a-vis natural gas prices. Projections by the Energy Information Administration (EIA) 

consistently indicate that domestic natural gas prices are likely to remain low and stable, while 

petroleum prices are likely to climb and exhibit greater volatility in the coming years and 

decades. 

In the light-duty greenhouse gas/fuel economy standards finalized by EPA and NHTSA in 

August 2012, the agencies acknowledged the importance of encouraging NGV adoption into the 

marketplace because of the key role NGVs will play as a technology bridge to hydrogenpowered fuel cell electric vehicles (FCEVs). 

The connection between NGVs and FCEVs is two-fold. First, technological developments 

related to on-board storage and fueling delivery, of compressed gases are likely to translate to 

some degree between both applications. Secondly, establishing a backbone of NGV 

infrastructure across the nation could lessen barriers to entry for FCEVs, since on-site reforming 

of hydrogen could provide fuel for FCEVs at stations initially established to serve an NGV 

market. 

Natural gas is an emerging market competitor to gasoline and diesel fuel. Automobile 

manufacturers and the petroleum industry have spent decades studying and adjusting the 

composition of petroleum-based fuels, balancing engine and exhaust system requirements with 

refining specifications. 

To date, end uses of natural gas have not had the same level of sensitivity to sulfur that is evident 

in vehicle applications. Because of this, little data is readily available concerning the sulfur 

content of CNG at the point of use. The American Gas Association is cognizant of the 

implications of sulfur content in CNG, and is currently working with the Coordinating Research 

Council (CRC) to support a national survey of natural gas fuel quality from the perspective of a 

motor fuel. This work was initiated in the fall of 2012, and is expected to yield results in the fall 

of 2013. Sulfur is among a number of the constituent components of CNG that is being tested as 

part of this work. 

We would welcome the opportunity to share the results of this initial survey of CNG fuel quality 

at the point of use for motor fuel - the CNG fueling station - when the results become available.

While a valuable first step in obtaining real-world data, we anticipate that additional work will 

likely be needed beyond the current CRC effort to provide a more complete national picture of 

CNG and sulfur content. AGA believes that a joint effort with EPA on data collection could be a 

valuable extension of this effort. 

While data on sulfur content of CNG at the point of use is lacking, some information on sulfur 

content in the natural gas distribution and transmission system is available. Operators of 

interstate pipelines impose limitations on sulfur content for natural gas injected into their 

systems, as part of their commitment to ensuring pipeline quality. In the presence of moisture, 

sulfur can form highly acidic compounds that corrode the interior of the pipe. Termed “tariff 

restrictions,” these industry standards for sulfur content vary nationally from 0.5 grains per 100 

standard cubic feet (grains/SCF) to approximately 20 grains/SCF. These standards correspond to 

levels between 8 ppm and about 300 ppm sulfur content. 
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It is extremely important to note that the 300 ppm standard is a maximum intended for unusual 

cases when natural gas producers do not have access to processing prior to injection into the 

pipeline. In real-world practice, natural gas with these higher levels of sulfur content are heavily 

diluted by the lower sulfur content gas that is in the norm in interstate pipelines.

Since the EPA request for comment was published, AGA has made initial inquiries to its 

members seeking data on sulfur content in their systems obtained at the city gate. As noted 

previously, traditional end-uses of natural gas in the residential and commercial sectors have not 

exhibited high sensitive to sulfur content, and so further data is not readily available. The AGA 

effort with the CRC is aimed at reducing uncertainty about CNG sulfur content by acquiring 

actual data at the consumer’s point of use. 

Additionally, it is critical to note that AGA member companies, as natural gas local distribution 

companies (LDCs), place the highest priority on the safety of their customers. For this reason, a 

sulfur-based odorant called mercaptin is introduced into the natural gas system by LDCs when 

they take possession of the natural gas at the city gate. This odorant is a critical safety measure 

that allows consumers to detect the presence of any natural gas leakage. The amount of sulfur 

introduced into the natural gas by mercaptin is approximately 5 ppm. We ask that, in 

considering any future sulfur standard for natural gas used as a motor fuel, that EPA weigh the 

importance of mercaptin as a safety measure. 

Commenter: Countrymark; Small Business Refiners (SBR)

We do not believe that sulfur standards need to be established for CNG or LNG. According to 

DOE statistics, natural gas is less than 5 ppm of all sulfur compounds. This is sulfur associated 

with natural gas production and an odorant that is required for leak detection. Additional 

standards would be unnecessary testing and documentation required by parties involved in the 

CNG and LNG business. This unnecessary cost of compliance will be passed on to end users, 

increasing energy costs with no benefits attained. 

Adding a sulfur standard for CNG and LNG increases the switching cost for consumers and may 

decrease corporation’s willingness to participate in the market. Additional testing and 

documentation without tangible benefits to suppliers, customers, or environmental benefits 

without positive results does not deliver value for any party involved in the process. 

Commenter: Private Citizen

We must be careful not to encourage CNG vehicles because the process used to extract natural 

gas in deep shale causes climate instability through methane releases, contaminates water, air, 

and food sources, and destroys communities. 

Commenter: Private Citizen

Please do not make the mistake of supporting a switch from oil to fracked gas. The extraction 

process for fracked gas pollutes air, water, and cropland, destroys wildlife habitat, depletes water 
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supplies, and buries millions of gallons of chemically compromised water thousand of feet 

underground where it can migrate and foul streams, lakes and rivers. 

As if this weren’t enough, thousands of trees are clearcut to make roads for the trucks that 

transport fracked waste water,, wildlife is impacted, communities are disrupted and the health of 

millions is in jeopardy. 

Support renewables. A nation cannot support itself without its natural resources upon which 

everything depends. 

Commenter: Manufacturers of Emission Controls Association (MECA)

MECA also supports defining fuel sulfur average limits or caps on any alternative transportation 

fuels (e.g., blends of alcohols with gasoline, natural gas) that are consistent with the proposed 10 

ppm national average for gasoline or the existing 15 ppm national sulfur cap on diesel fuel. 

Commenter: National Propane Gas Association (NPGA)

With respect to fuel specifications, EPA is proposing to reduce the maximum sulfur content in 

gasoline from the current 30 parts per million (ppm) to 10 ppm on an annual average basis 

beginning January 1, 2017. EPA is also proposing a sulfur maximum on a per-gallon basis with 

caps set at 80 ppm at the refinery gate and 95 ppm at any downstream locations. The Agency is 

also seeking input on changes to emissions test fuel specifications.

Although EPA’s Tier 3 proposal is described as being fuel-neutral, there are elements of the 

proposed rule that could impact propane autogas, and as such, NPGA submits the following 

comments on the Tier 3 proposal. 

As previously stated, EPA is seeking to lower the maximum sulfur content for gasoline, on an 

annual average basis, from the current 30 ppm to 10 ppm. In doing so, EPA states that this will 

“enable vehicles designed to the proposed Tier 3 tailpipe exhaust standards to meet these 

standards in-use for the duration of their useful life and facilitate immediate emission reductions 

from all the vehicles on the road at the time the sulfur controls are implemented.” 

The proposed changes to fuel specifications specifically apply to gasoline. However, EPA also 

requests input on whether it is necessary to establish sulfur standards for alternative fuels such as 

liquefied petroleum gas (LPG), i.e. propane autogas, and compressed natural gas (CNG) given 

that no such standards exist for these vehicles. In addition, EPA asks whether a 15 ppm sulfur 

cap similar to that established for highway diesel fuel would be appropriate. EPA also solicits 

input on the contribution of sulfur from odorants used in LPG. 

With respect to sulfur standards for alternative fuels, NPGA understands that EPA is simply 

seeking input on this subject and not actually specifying a proposed sulfur maximum at this time. 

We further recognize that a specific proposal to this effect would have to be addressed under a 

separate rulemaking activity to allow for proper review by the public, which it cannot perform 
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within the context of this NPRM since there is no maximum number proposed upon which to 

evaluate. 

Nevertheless, the establishment of a sulfur maximum for LPG, i.e. propane autogas, presents a 

unique challenge that does not exist for gasoline or diesel fuel. Unlike gasoline or diesel fuel, 

propane autogas is odorless. Therefore, for safety reasons, federal hazardous materials 

regulations require that it be odorized to a level that indicates the presence of gas down to a 

concentration in air of not over 1/5 the lower flammability limit of LPG. 

Further to this, NFPA 58, LP-Gas Code, requires that the fuel be odorized prior to delivery to a 

bulk plant (4), where the fuel is stored for subsequent distribution for vehicle fuel purposes or for 

other applications such as space or water heating. To meet these odorization requirements, it has 

been a long-standing industry practice to inject an odorant named ethyl mercaptan to the fuel. 

Ethyl mercaptan is a sulfur-based odorant and is, without question, the most commonly used and 

available odorant in the United States. It is injected at a recommended rate of 1 pound per 10,000 

gallons of LPG. For conservatism, it is not uncommon to see a slightly higher injection rate at 

1.5 pounds per 10,000 gallons. This equates to approximately 15-20 ppm of sulfur that would be 

present in the fuel after it leaves the refinery or gas processing plant and prior to arrival at a retail 

marketer’s bulk plant. 

NPGA does not believe that EPA should place maximum sulfur content requirements on propane 

autogas at this point in time for several reasons. First, consider that the establishment of sulfur 

maximums for gasoline and diesel require actions on the part of refiners or gas processors that 

would remove sulfur from the fuel. Likewise, with propane autogas, similar actions would be 

required for the removal of sulfur that may exist in the form of constituents such as carbonyl 

sulfide or hydrogen sulfide. 

However, where things differ between the fuels is the required addition of a substance that 

contains sulfur as a constituent, namely ethyl mercaptan, which is an important and necessary 

safety measure. In doing so, this adds a layer of complexity to the issue of sulfur removal that 

would need to be fully vetted outside the construct of this proposed rulemaking to ascertain, if 

possible, where the proper balance exists between appropriate levels of sulfur removal and the 

need to maintain safety for a fuel that is used in applications beyond just vehicles. 

Second, EPA would have to account for a variety of economic impacts including, among other 

things, the cost to produce low-sulfur propane autogas. In addition, EPA would need to take into 

account the cost impact on new or potentially separate fuel storage needs and capabilities for 

retail marketers of propane autogas to avoid intermixing the low-sulfur fuel with the fuel for 

non-vehicle applications. 

Lastly, EPA solicits input on whether a 15 ppm sulfur cap similar to that established for highway 

diesel fuel would be appropriate. NPGA does not believe it would be appropriate to follow a 

similar approach to diesel. The current 15 ppm diesel requirement applies to all downstream 

locations, including distributors and retailers, which could be very problematic for retail autogas 

marketers. 
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In addition to all of the aforementioned factors that EPA must take into account when 

considering this subject, NPGA has a practical concern related to the establishment of sulfur 

maximums. In particular, by establishing a cap for gasoline, it begs the question as to what 

should be an appropriate maximum level for alternative fuels such as propane autogas and CNG, 

and it suggests there could be unintended consequences without a sulfur maximum. However, it 

would be impossible to realistically answer these questions given the extreme time constraints 

for responding to this complex NPRM imposed by EPA as it would require broad, collaborative 

input from all interested stakeholders such as fuel suppliers, fuel providers and those who 

develop the fuel specifications to determine the answers. 

________________________________________

4 - National Fire Protection Association (NFPA) 58, LP-Gas Code, 2011 Edition, Section 4.

Commenter: New York State Department of Environmental Conservation

Gaseous fueled vehicles need to be held to the same standards as liquid fuels. 

EPA has requested comment regarding the sulfur content of natural gas and propane when used 

to fuel light duty vehicles. This issue is complicated by the fact that sulfur containing chemicals 

(mercaptans) are added to these gases to facilitate leak detection. 

We believe that the competing demands of maintaining catalyst efficiency and ensuring adequate 

odorant levels can be met. We do not support relaxing the Tier 3 emission standards for gaseous 

fueled vehicles as an accommodation to mercaptan sulfur levels in these fuels. 

Commenter: NGVAmerica

The Tier 3 rulemaking proposes to establish new, lower limits on the sulfur levels in gasoline 

and diesel fuel. The expected advantages of lower sulfur are the ability to provide not only lower 

emissions in new vehicles but also continued lower emissions over the life of such vehicles. The 

rulemaking also requests comment on whether EPA should impose similar sulfur requirements 

on natural gas when used as a motor vehicle fuel.

The proposal requests comment on whether natural gas should have to meet an in-use standard as 

well as a test fuel standard. EPA regulations currently include test fuel standards for natural gas 

but do not include any controls on sulfur levels.

EPA’s notice specifically asks whether it should impose a 15 ppm sulfur limit for natural gas. 

While we can understand the desire to impose similar performance standards on all motor 

vehicle fuels, we believe that it is not appropriate to impose any limits on natural gas for the 

following reasons:

1. The rulemaking record does not demonstrate that current natural gas sulfur levels need to be 

controlled in order for NGVs to meet the proposed emission standards; 

2. The rulemaking record has not identified how sulfur levels would be controlled while 

maintaining appropriate odorant levels; 
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3. The rulemaking record has not identified who – producers, pipelines, gas utilities, fueling 

station operators – would be responsible for controlling sulfur limits in natural gas; and 

4. The rulemaking record has not identified appropriate technologies for lowering sulfur in 

natural gas or the cost of these technologies and, therefore, no cost-benefit analysis has been 

conducted.

Based on the foregoing and as explained here, it would be premature to establish test-fuel 

specifications or in-use specifications for natural gas sulfur levels.

In preparing these comments, NGVAmerica consulted with industry experts in order to 

determine whether the industry currently has data on current sulfur levels. The most 

comprehensive assessment of natural gas fuel quality of which we are aware was conducted in 

1992 by the Gas Research Institute (now Gas Technology Institute) (1). According to GTI 

officials, total sulfur was typically in the range of 0.34-0.39 grains/100 scf or about 9 - 13 ppm, 

mass basis. Maximum levels of 0.6-0.7 grains (18 - 22 ppm) were noted, but this was relatively 

rare. Transmission pipeline (non-odorized) gas was typically around 0.12 grains/100 scf (about 4 

ppm). Based on these figures it appears that the levels contemplated by EPA would not present a 

problem for natural gas providers. Conversations with a major natural gas producer and also with 

one of the nation’s largest natural gas utilities indicates that the natural gas they produce and 

deliver to customers also would be in line with the levels proposed by EPA. 

We believe that these factors suggest that, rather than supporting the setting of a new national 

standard for natural gas, there likely is no need for such a standard. Moreover, we are extremely 

hesitant to support a 15 ppm level because the GRI data is now more than 20 years old, and we 

do not have enough comprehensive, recent data to support a 15 ppm level. Further, it would be 

unwise to support such a level without having an understanding of how sulfur would be 

controlled if, in fact, it needs to be controlled, and by whom would it be controlled. 

Unlike the regulatory record compiled with respect to the petroleum industry and sulfur controls, 

there has not been an engagement with the natural gas industry – producers, pipelines, fuel 

providers, equipment suppliers, etc. – with respect to the technology that would be used to 

control sulfur levels. And unlike the example of the petroleum industry, it is not at all certain that 

the best means or the most efficient means of controlling sulfur limits in natural gas would be to 

control levels upstream as is the case with petroleum where sulfur is controlled at the refinery. 

Given that most natural gas is currently consumed for non-transportation purposes (electric 

generation, heating, industrial processes), it seems unlikely that EPA would or could legally 

impose upstream sulfur controls on the natural gas industry without a strong showing that such 

levels are necessary for other regulatory purposes. Therefore, it would appear that, if controls are 

necessary, they would be imposed at the fueling station. This presents more questions about what 

technologies would be used and how this would impact odorant levels since the odorant itself 

contains sulfur. The odorant (mercaptan) is added as a safety feature so that leaks of natural gas 

will be recognized. If the sulfur is pulled out presumably some odorant will have to be put back 

in at added costs and difficulty at the fueling station. All of these issues must be fully explored 

before a national standard can be set.
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The questions raised by this rulemaking and any proposed sulfur limits on natural gas must be 

fully explored and considered before moving forward. Therefore, we would urge the EPA to 

forgo establishing new controls on natural gas sulfur levels. EPA should instead work with the 

natural gas industry to assess whether there is a need for a national sulfur standard, i.e. whether 

sulfur levels in natural gas present an emission issue for certifying new natural gas vehicles. 

These discussions should also begin to assess what types of technologies are available to control 

sulfur levels if in fact sulfur levels need to be controlled. 

1 - Gas Research Institute, American Gas Association Laboratories, GF Steinmetz, Institute for Gas 

Technology, Variability of Natural Gas Composition in Select Major Metropolitan Areas of the United 

States 1990 – 1992 (March 1992).

Commenter: Pennsylvania Department of Environmental Protection (DEP)

The EPA should decide whether to require the same sulfur content in natural gas in order to 

attain the same emissions standards in natural gas-powered vehicles as those proposed for 

gasoline-powered vehicles.

As specified in the Preamble for the proposed Tier 3 rule, there are currently no sulfur 

specifications for the test fuel used for certifying natural gas vehicles nor for the test fuel used 

for certifying liquefied petroleum gas (LPG) vehicles (78 FR 29,914). In addition to seeking 

comments on the appropriateness of amending 40•CFR section 86.113 to reference 40 CFR Part 

1065 for both natural gas and LPG test fuels, EPA also requested comments on amending the 

specifications to better reflect in-use fuel characteristics. Additionally, EPA requested comment 

on the appropriateness of aligning the sulfur specifications with those that apply for gasoline test 

fuel.

Sulfur levels in natural gas are typically lower than sulfur levels in gasoline by two orders of 

magnitude. Sulfur levels in gasoline average 0.034 percent currently and will be reduced to 0.012 

percent. Sulfur levels in natural gas average 0.0005 percent sulfur from the wellhead. Natural gas 

providers add odorants to the natural gas, however, that can have high levels of sulfur. Natural 

gas-powered vehicles will have the same control equipment installed as is installed on gasolinepowered vehicles. EPA should determine if it is appropriate to establish a standard for sulfur in 

natural gas that will be used in natural gas-powered vehicles, including sulfur in the odorants that 

would meet the same vehicle standards that Tier 3 gasoline-powered vehicles would be required 

to meet under EPA’s proposed rule. 

Commenter: Robert Bosch GmbH, Gasoline Systems, Germany

The best approach would be a standardization on a basis of the actual CEN standardization for 

CNG fuel in Europe. 

Commenter: Private Citizen

The solution to the pollution problem is right under your noses! Natural gas! All internal 

combustion and turbine engines run quite well on it. It’s clean, non-polluting, and cheap! Why 

won’t you acknowledge it? Has big oil tied your hands? With the finding of huge pockets of it 
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popping up everyday, one would think of it was a God send. What’s holding up start? City and 

state, and federal government would use it and benefit hugely. Saving monies, cleaning the 

atmosphere, etc.. Don’t send it overseas to benefit countries that are not our friends. Benefit us! 

Equipment using it lasts longer, goes longer between oil changes, requires less tune ups, burns 

cleaner. It doesn’t require a rocket scientist to figure this out. Jump on the band wagon, do 

something right for a change. Now, everything has been built to run on up to 10% ethanol. I hear 

whispers about you people wanting to raise that limit to 15% ethanol. Won’t work! As of today,

some small engine manufacturers are telling their users to use mid-grade gasoline to correct 

starting, running, and performance problems. Think of the impact on people if they have to 

purchase new equipment to do lawn work. What of the people who are forced to purchase new 

cars?

Commenter: VNG.CO

VNG.CO (VNG) submits these Comments in the above-referenced docket. Based in 

Pennsylvania, VNG is developing a nationwide, retail compressed natural gas (CNG) fueling 

network specifically for light duty vehicles. VNG will be collocating its CNG fueling facilities at 

existing gasoline stations in order to provide a convenient and familiar fueling experience. While 

initially serving corporate fleets, VNG’s fueling facilities will also support mass market adoption 

of natural gas vehicles (NGVs) and can be adapted to dispense advanced gaseous fuels like 

renewable natural gas (RNG) and hydrogen. VNG offers its recommendations below because the 

EPA’s consideration of motor vehicle emissions and fuel standards may impact the development 

of the NGV market in ways the EPA may not have considered. 

It is widely recognized that the shale gas revolution has transformed the U.S. energy landscape 

with its promise of abundant, low-cost natural gas supplies for decades to come. This has led to a 

growing interest in natural gas vehicles (NGVs), which offer major environmental, economic, 

and security benefits compared to petroleum-based gasoline and diesel fuels. While the NGV 

industry has historically focused on the heavy-duty segment, this sea change in US energy 

production has also led to increasing attention on the potential of light-duty NGVs by 

automakers, compressed natural gas (CNG) refueling service providers like VNG, and 

policymakers – particularly at the federal level: 

• President Obama has repeatedly hailed the importance of both light-duty and heavy-duty 

natural gas vehicles, including in his 2012 Blueprint for an America Built to Last1 and his 2013 

Blueprint for a Clean and Secure Energy Future. (2) 

• The National Petroleum Council of the U.S. Department of Energy and the National 

Academy of Sciences have both recently released comprehensive studies of alternative fuels 

which have found NGVs to have the greatest potential for mass-market adoption and reductions 

of oil use of any light-duty vehicle technology over of the next two decades. (3,4)

• EPA acknowledged the potential of light-duty NGVs to accelerate the commercialization 

of zero-emission hydrogen fuel cell electric vehicles (FCEVs) in the 2017-2025 light-duty GHG 

rules, awarding these vehicles special multiplier incentives to stimulate their development. (5) 

However, despite this growing recognition of the potential of light-duty NGVs to reduce air 

pollution, reduce petroleum imports and reduce consumers’ fuel costs, the market for these 

vehicles is still at a nascent stage. While refueling service providers such as VNG are making 
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progress in expanding natural gas fuel availability, there are still just over 1,200 CNG fueling 

stations nationwide – fully half of which are not accessible to the public6 – compared to about 

100,000 gasoline stations.7 Light duty NGV product offerings are limited to the Honda Civic 

Natural Gas, dual-fuel NGV pickups from GM and Chrysler, and a variety of offerings from 

conversion companies (notably Westport, IMPCO, and others) – all of which are currently being 

produced and sold in the U.S. at very low volumes and high incremental costs compared to 

similar models powered by gasoline or diesel fuel. 

Given the tenuous stage of the development of this market, it is critical that new regulations such 

as the Tier 3 regulations do not place unnecessary burdens on the industry. Rather, wherever 

possible the Tier 3 regulations should encourage the development of the market for light duty 

NGVs. This can be assured in two ways:

• Avoiding the implementation of sulfur content regulations for CNG. There is no evidence 

that such rules are needed, and the implementation of such regulations for natural gas 

transportation fuel raises unique issues compared to regulations applicable to gasoline.

• By avoiding unnecessary regulatory burdens on CNG fuel as well as reducing existing 

and future inequalities in the vehicle certification process, EPA could play an important role in 

accelerating the development of the NGV industry by reducing incremental costs to consumers, 

with no reduction in the overall efficacy of the Tier 3 program. Achieving this would be 

consistent with EPA’s mandates under the Clean Air Act as well as Executive Order 13563: 

Improving Regulation and Regulatory Review – which, among other things, calls for regulations 

that “promote economic growth, innovation, competitiveness, and job creation,” through use of 

“the least burdensome tools for achieving regulatory ends” as well as “flexible approaches.” (8)

In the Notice of Proposed Rulemaking (NPRM), EPA requests comment on whether it is 

necessary to “establish sulfur standards for CNG and LPG fuels, and whether a 15 ppm sulfur 

cap similar to that established for highway diesel fuel would be appropriate,” potentially on the 

grounds of EPA’s intent to make the regulations “fuel neutral.”9 However, because of the 

inherent differences between natural gas and gasoline, it would be inappropriate for EPA to 

regulate the sulfur content in CNG. 

There is no evidence that the sulfur content of CNG fuel is sufficient to impact the catalyst 

efficiency of NGVs;

. There is no data on the average sulfur content of natural gas, and gas composition will in any 

case vary significantly between different regions;

. There is no evidence or information about the means or costs for regulating the sulfur content 

of natural gas motor vehicle fuel; and 

. Unlike gasoline, which is only used as vehicle fuel, the natural gas compressed for CNG is 

used for a wide range of purposes (power plants, home heating, etc.) which do not and will not 

have sulfur regulated. 

Thus, imposing sulfur regulations on CNG vehicle fuel has not been shown to be necessary, 

would have uncertain costs, and risks discouraging the use of natural gas as a vehicle fuel. If 

sulfur regulations were imposed on upstream natural gas producers or utilities, these entities (and 

their many customers) would object to the additional cost of processing 100 percent of their 

natural gas supplies to comply with a regulations that would currently apply to the less than 0.2% 
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of total US gas demand used for transportation.10 Alternately, if the burden of compliance were 

to fall on downstream CNG retailers, it would impose unknown additional costs at every CNG 

dispensing site that would have to be recovered from relatively low volumes of fuel, making it 

even more difficult for natural gas to replace petroleum-based motor vehicle fuels, contrary to 

EPA’s goals. 

Regardless, much more data on the levels of sulfur currently present in natural gas, the impacts 

of this sulfur on NGV emissions, and the means and costs for reducing this sulfur content should 

be obtained before any potentially costly decisions to regulate the sulfur content of natural gas 

motor vehicle fuel are made. 

1 Slack, Megan. “Everything You Need to Know: President Obama’s Blueprint for American-Made 

Energy.” White House Blog. 26 Jan 2012. http://www.whitehouse.gov/blog/2012/01/26/everything-youneed-know-president-obamas-blueprint-american-made-energy?twp=twt

2 White House. “FACT SHEET: President Obama’s Blueprint for a Clean and Secure Energy Future.” 5 

Mar 2013. http://www.whitehouse.gov/the-press-office/2013/03/15/fact-sheet-president-obama-sblueprint-clean-and-secure-energy-future

3 National Petroleum Council. “Future Transportation Fuels: Natural Gas Analysis.” 28 May 2013. 

http://www.npc.org/FTF-report-080112/Chapter14-NaturalGas-052813.pdf

4 National Academy of Sciences. “Transitions to Alternative Vehicles and Fuels.” March 2013. 

http://www.nap.edu/catalog.php?record 

5 Environmental Protection Agency. “2017 and Later Model Year Light-Duty Vehicle Greenhouse Gas 

Emissions and Corporate Average Fuel Economy Standards; Final Rule.“ Federal Register, 15 Oct 2012, 

p. 62815.http://www.gpo.gov/fdsys/pkg/FR-2012-10-15/pdf/2012-21972.pdf

6 Alternative Fuels Data Center. “Alternative Fueling Station Locator.“ Department of Energy, Energy 

Efficiency and Renewable Energy Program. Accessed 28 June 2013. 

http://www.afdc.energy.gov/locator/stations/

7 U.S. Census Bureau. “Economic Census, Industry Snapshot: Gasoline Stations with Convenience 

Stores.” 2007. http://www.census.gov/econ/census/pdf/44711.pdf

8 The White House. “Executive Order 13563 – Improving Regulation and Regulatory Review.” 18 Jan 

2011.

http://www.whitehouse.gov/the-press-office/2011/01/18/improving-regulation-and-regulatory-reviewexecutive-order

9 Environmental Protection Agency. “Control of Air Pollution From Motor Vehicles: Tier 3 Motor 

Vehicle Emission and Fuel Standards; Proposed Rule.” Federal Register, 21 May 2013, p. 29826.

10 Energy Information Administration. “Annual Energy Outlook 

2013.” http://www.eia.gov/forecasts/aeo/

Our Response:

As discussed in Section V.J. of the preamble to the final rule, EPA is deferring finalizing 

in-use sulfur requirements for CNG/LPG in this final rule to provide additional time to work 

with stakeholders to collect data on current CNG/LPG sulfur content, to determine whether 

additional control of in-use CNG/LPG sulfur content is needed, and to evaluate the feasibility 

and costs associated with potential additional sulfur controls. Given that the information in the 

public comments suggests already low sulfur levels in CNG/LPG, the Tier 3 program vehicle 

emissions standards will apply to CNG/LPG vehicles in addition to vehicles fueled on gasoline, 

diesel fuel, or any other fuel.
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For those comments that suggested that EPA should either promote the use of natural gas 

or constrain its use due to concerns over fracking, such comments are beyond the scope of the 

Tier 3 rulemaking. We sought comment only on the sulfur standards for CNG and LPG if they 

are used in motor vehicles. 

5.7.3. Other

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Market fuel gasoline RVP for the summer season should be capped at 9 psi RVP, including 

within that the statutory one pound waiver for E10. 

Our Response:

The regulation of gasoline RVP is beyond the scope of the Tier 3 final rule.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

Combined with other regulations, such as the RFS2, this rule would impact domestic fuel 

supplies, result in increased consumer costs, and affect energy security. 

Our Response:

Given the estimated costs and impacts of the Tier 3 program, as discussed in both the 

preamble to the final rule and in the RIA, we do not expect this rule to negatively effect U.S. 

energy security – or the supply or distribution of gasoline or other fuels.

What Commenters Said:

Commenter: Private Citizen

As an intermediate transition from the continued dependence on poisonous polluting carbonbased fuels, I support the new Vehicle and Gasoline Standards. However, I also support rapid 

replacement of such fuels by one that is totally clean (no pollution) and requires no new 

technological development: hydrogen, derived from water by electrolysis, will make us totally 

energy-independent. Air, land, and oceanic vehicles can burn liquid hydrogen. The massproduced cost of transforming existing motor vehicles’ engines to run on hydrogen instead of 
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gasoline will be one-tenth the cost of replacing them all with electric vehicles, and no mining or 

drilling is required as is the case with needed battery-replacement raw materials. The electricity 

needed to produce hydrogen needs to come from natural solar, wind, and tidal-current sources. A 

solar-hydrogen economy will result in 99% less pollution! Study descriptions by International 

Society of Hydrogen Engineers scientist Harry Braun at http://PhoenixProjectFoundation.US ... 

also consider the arguments for Lunar Solar Power (eight times more efficient, without 

occupying any human habitat areas, and allowing direct energy transfer to all urban centers on 

Earth), by scientist David Criswell – a noble plan using proved technology to bring cheap 

electricity to every person on Earth... http://lunarsolarpowersystem.blogspot.com (developing 

now, a new website, http://lunarsolarpower.org will promote LSP). 

Our Response:

The Tier 3 program vehicle emissions standards are fuel neutral (i.e., they apply 

regardless of the type of fuel that vehicle uses, including hydrogen). The promotion of 

alternative energy sources (including solar energy) is beyond the scope of the Tier 3 final rule.

What Commenters Said:

Commenter: Private Citizen

Let’s transform our cars so they can run on alcohol fuel. Please make it legal for retailers to buy 

wholesale from local alcohol fuel plants E-100 Ethanol. Make it legal for local communities to 

operate local alcohol fuel plants in zones recognized as industrial for sustainable fuel and energy 

rather than in zones recognized as heavy industrial. Please make it the law that automobile 

manufactures must install dedicated ethanol engines in a high percentage of all new cars. If all of 

the above is done, then local economies will be revived; our air, land, and water would become 

clean again; and perpetual war in Afghanistan and the Mid East Region will end. We must 

become a nation dedicated to sustainable fuel. Support ethanol fuel and support the Tier 3 clean 

vehicle and gasoline standards. 

Our Response:

The Tier 3 program vehicle emissions standards are fuel neutral (i.e., apply regardless of 

the type of fuel that vehicle uses, including E100.) The consideration of a potential requirement 

to mandate the production of dedicated E100 engines by automobile manufacturers is beyond the 

scope of the Tier 3 final rule.

What Commenters Said:

Commenter: Private Citizens

The proposed fuel and emissions law changes are good, but the increases in automobile prices 

and gasoline are not. These so called higher prices for cars and the fuel used, is not the answer. 
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The use of more alcohol in motor fuel is. Cleaner burning engines of today can use 10-15 

percent gasoline to 80-85percent alcohol, that is the combination that can reduce emissions. Fuel 

additives can come from all types of renewable sources, and reduce the oil imports plus lower 

fuel cost. The keystone pipeline should be built, and have a second source of refining, the east 

coast of NY and NJ—there are huge refineries there and can handle the oil to be processed. 

Our Response:

The Tier 3 program vehicle emissions standards are fuel neutral (i.e. apply regardless of 

the type of fuel that vehicle uses, including higher level ethanol blends.) The construction of the 

Keystone pipeline is beyond the scope of the Tier 3 final rule.

What Commenters Said:

Commenter: Mercedes-Benz USA, LLC on behalf of Daimler AG

To provide Mercedes-Benz and other OEMs a degree of certainty and incentive that costs 

associated with the design, development, certification and production of vehicles dedicated to 

operation on Tier 3 Fuel are wise investments in the future of the US and global environments, 

Mercedes-Benz requests the following:

EPA grant a reduction in the Mercedes-Benz (or OEM) total annual corporate CO2 compliance 

burden, based on the following equation per vehicle model certification family and a CO2 

Burden Reduction Multiplier:

CO2 Burden Reduction =

CO2 output on Tier 3 certification fuel/equivalent CO2 output on 91 AKI Tier 2 E0 certification 

fuel x projected annual sales percentage of corporate gasoline-powered vehicles optimized for 

operation on Tier 3 fuel by MY / total corporate gasoline-powered vehicle sales projection by 

MY x annual OEM corporate CO2 projected output 

As an incentive for early adoption of Tier 3 Fuel capability, the CO2 Burden Reduction 

Multiplier would be applied according to this schedule:

MY 2016 and prior: 100% of CO2 Burden Reduction

MY 2017-2019: 50% of CO2 Burden Reduction

MY 2020-2022: 25% of CO2 Burden Reduction

MY 2023 and later: no additional CO2 Burden Reduction

In the event of limited Tier 3 fuel availability nationwide, but where the necessary hardware to 

support Tier 3 fuel usage has already been incorporated in vehicle models MY2016-2022 as well 

as prior, Mercedes-Benz requests the following: 

EPA grant a reduction in the Mercedes-Benz (or OEM) total annual corporate CO2 compliance 

burden, based on the CO2 Burden Reduction equation per vehicle model line:
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MY 2016 and prior: 50% of the CO2 Burden Reduction

MY 2017-2019: 25% of CO2 Burden Reduction

MY 2020-2022: 15% of CO2 Burden Reduction

MY 2023 and later: no additional CO2 Burden Reduction 

These corporate CO2 burden reductions would end MY 2023 or 90% retail station penetration of 

a high-octane mid-blend ethanol retail fuel, whichever comes first. 

In order to provide incentive for fuel producers to achieve an expedient and substantial 

marketplace penetration of a Tier 3 fuel similar to the proposed certification fuel, it is further 

proposed that a Federal Fuels Tax discount or equivalent RIN credit be applied to each gallon of 

Tier 3 fuel produced for US consumption. This discount or credit would be equal to:

Producer Credit = 1.00 - (net heating value of the Tier 3 certification fuel divided by the NHV of 

91 AKI Tier 2 E0 certification fuel). 

This Producer Credit would also expire MY2023 or after 90% retail penetration of a Tier 3 is 

achieved, whichever comes first.

13 - Resources for the Future, Reassessing the Oil Security Premium (February 2010), available at 

http://www.rff.org/RFF/Documents/RFF-DP-10-05.pdf. 

14 - Renewable Fuels Association, Battling for the Barrel: 2013 Ethanol Industry Outlook, p. 1, supra. 

15 - See Stein et al., An Overview of the Effects of Ethanol-Gasoline Blends on SI Engine Performance, 

Fuel Efficiency, and Emissions, supra. 

16 - MathPro Inc., Analysis of the Refining Costs and Associated Economic Effects of Producing 92 AKI 

Gasoline in the U.S. Refining Sector (October 30, 2012). 

17 - Stillwater Associates, The Cost of Introducing an Intermediate Blend Ethanol Fuel for 2017- andLater Vehicles, (October 17, 2012). 

Our Response:

Consideration of greenhouse gas requirements for vehicle manufactures and potential 

federal fuel tax credits are beyond the scope of the Tier 3 rulemaking.

What Commenters Said:

Commenter: Private Citizens

I am disappointed in the fact that neither the EPA nor UCS can’t come up with a better method 

of cleaning up automobile exhausts. It is time to stop using fossil fuels to produce our energy and 

switch to a hydrogen economy in which hydrogen is used in combination with fuel cells. The 

only exhaust is pure drinkable water. 

As a weak secondary alternative, I would support the Tier 3 standards for tailpipe emissions and 

low-sulfur fuel, and urge the EPA to finalize these standards by the end of 2013. 
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Every major automobile manufacturer is designing new fuel cell automobiles. Why can’t the 

EPA and federal government learn more about what’s going on in many countries where the 

number of fuel cell autos and buses are on the increase. It’s time to get with it! 

While we’ve made progress cleaning up our cars and trucks in recent years, they remain a 

leading source of air pollution. More than one in three Americans still live in areas where air 

pollution levels exceed at least one federal health standard. Hydrogen fuel cell autos would 

correct this. 

The Tier 3 standards would only reduce smog-forming pollutants and soot, which pose a 

particular danger to those suffering from asthma and other lung ailments. A hydrogen economy 

would not only REDUCE the pollution but would STOP it. 

Meeting the Tier 3 standards is achievable and necessary for our health. That’s why public health 

and environmental justice advocates, automakers, and state air quality regulators, environmental 

and science-based advocacy groups all support Tier 3. The only one standing in the way is the oil 

industry and their allies in Congress, but we can’t wait for their green light to clean up our air. 

More important, we can’t wait for the EPA and UCS to stop supporting the fossil fuel industry. 

Our Response:

The Tier 3 program vehicle emissions standards are fuel neutral (i.e., apply regardless of 

the type of fuel that vehicle uses, including hydrogen.) The promotion of the use of hydrogen as 

a motor fuel is beyond the scope of the Tier 3 final rule.

What Commenters Said:

Commenter: Monroe Energy, LLC 

Monroe operates a petroleum refinery in Trainer, Pennsylvania. As a merchant refiner, Monroe 

can only comply with its RFS2 obligations by purchasing renewable identification numbers 

(RINs). The recent and ongoing spike in the price of RINs will require Monroe to spend, on an 

annual basis, a very significant amount of money to comply with RFS2. Requiring Monroe to 

spend such additional capital investments to comply with the Tier 3 gasoline sulfur standards, 

and its nominal environmental benefit, will compound Monroe’s (and other merchant refiners’) 

economic injury. Therefore, EPA should not promulgate a Tier 3 sulfur standard until it has 

corrected the errors in the RFS2 rule.

The costs of compliance should not be evaluated in a vacuum; rather, they need to be balanced 

against other federal and state regulations, including the renewable fuel standard (RFS2). 

Our Response:

Issues pertaining to a refiner’s annual RFS2 obligations are being addressed in separate 

EPA actions and are beyond the scope of the Tier 3 rulemaking. We do not believe there is 

compelling reason to link the completion of the annual RFS2 rulemakings on the RFS volume 
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obligations to the promulgation of the Tier 3 final rule. Issues associated with the costs to 

refiners in complying with the Tier 3 sulfur requirements are addressed in Chapter 7.2 and the 

cost effectiveness of the Tier 3 sulfur requirements is addressed in Chapter 7.3 of this Summary 

and Analysis of Comments document.
Tier 3 Summary and Analysis of Comments

6-1

6 Regulatory Streamlining and Technical Amendments

What We Proposed:

EPA proposed a range of technical amendments and regulatory streamlining actions as 

part of the Regulatory Review initiative. Some of these may have some bearing on 

implementation of the Tier 3 vehicle and fuel standards, while others deal with other aspects of 

EPA’s existing fuel and vehicle regulations. The comments in this chapter correspond to Section 

VI of the preamble to the proposed rule. A summary of the comments received and our response 

to those comments are located below.

6.1. Fuels Program

6.1.1. Regulatory Streamlining and Tech Amendments

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

We appreciate EPA effort to make regulatory streamlining a priority. We support the elimination 

of unnecessary and outdated provisions in order to improve administrative efficiency and reduce 

regulatory compliance burdens. These proposed streamlining provisions are independent of Tier 

3 and should be finalized earlier than the Tier 3 final rule. We agree with the Agency that these 

are straightforward and should be implemented quickly. 

EPA has made regulatory streamlining a priority and we appreciate the Agency’s efforts. We 

agree that regulatory streamlining will result in more efficient and less costly compliance. We 

support the elimination of unnecessary and outdated provisions. These provisions are 

independent of Tier 3 and should be promulgated in a final rule earlier than the Tier 3 final rule. 

We agree with the Agency that these are straightforward and should be implemented quickly. 

Commenter: Irving Oil Terminals Inc.

EPA has proposed a number of regulatory changes to the Gasoline Program such as (1) reducing 

testing and reporting requirements of certain RFG parameters during the winter months; (2) 

updating of test methods for various fuel parameters; (3) designation of an alternative, 

independent laboratory; (4) elimination of unnecessary diesel fuel pump labeling; (5) extension 

of Performance Based Measurement System to other fuel parameters and test methods; (6) 

provision for de minimis changes in batch volume reports, and (7) attest engagements. Irving Oil 

supports these proposals. They would streamline registration, recordkeeping and reporting, 

reduce costs and free up personnel to focus on more significant areas of compliance. 

Commenter: Marathon Petroleum Company LP (MPC)
Chapter 6: Regulatory Streamlining and Technical Amendments

6-2

MPC also supports the fuel streamlining steps that EPA has identified and is willing to work with 

EPA to identify further streamlining actions that can be taken. EPA has made regulatory 

streamlining a priority and we appreciate the Agency’s efforts. We agree that regulatory 

streamlining will result in more efficient and less costly compliance. We support the elimination 

of unnecessary and outdated provisions. These provisions are independent of Tier 3 and should 

be promulgated in a final rule earlier than the Tier 3 final rule. We agree with the Agency that 

these are straightforward and should be implemented quickly. 

Commenter: PBF Energy Inc.

PBF supports the regulatory streamlining efforts included in the proposed rule. 

Commenter: Phillips 66 Company

We are appreciative of the effort to streamline various portions of existing regulations. With 

changes over time, there are several areas that need “clean-up” and this effort will reduce 

confusion and burden on the regulatory parties. We offer the following comments on the 

proposed revisions as well as suggestions for other provisions that we feel would add value and 

should be considered. 

Our Response:

EPA appreciates the industry support for the current effort to streamline applicable 

regulatory provisions in a timely and environmentally sound manner.

6.1.1.1. Complex Model Testing & Reporting

EPA proposed several amendments related to the reduction of testing and reporting of 

complex model gasoline parameters.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

We support the initiative to streamline testing and reporting for EPA’s Complex Model, 

including the eliminating API gravity and oxygenates. We also recommend that the requirement 

for aromatics, distillation, and olefins be eliminated completely for winter Reformulated and 

Conventional gasoline batches. API and AFPM recommend additional regulatory changes to 

eliminate testing that provides no value, is redundant or otherwise unnecessary. In addition, we 

recommend reporting frequency and deadlines be changed to meet the needs of EPA and the 

regulated parties, and EPA update regulatory references to the most up to date standards. 
Tier 3 Summary and Analysis of Comments

6-3

Testing and reporting for Complex Model fuel parameters: EPA proposes to reduce the testing 

and reporting burden for individual batches of RFG and conventional gasoline (CG). Many of 

the tests for individual parameters are no longer needed because of the phase out of complex 

model standards. The complex model standard for NOx was replaced by the Tier 2 gasoline 

sulfur standard. The toxics complex model standard was replaced by MSAT2 (43). The only 

remaining complex model standard for most refineries is summer RFG VOCs. 

We support the Agency’s proposal to eliminate API gravity. This is proposed to be effective on 

January 1, 2013 (see proposed 80.65(e)(3)). Given that the proposal was published in the Federal 

Register on May 21, 2013, this proposed effective date may be confusing because of its 

retroactive nature. Refiners recommend that the effective date remain January 1, 2013 in the final 

rule. 

We support EPA’s proposal to eliminate testing and reporting for oxygenates (unless necessary 

because oxygenates added downstream are used in calculations). The effective date of this 

elimination should be no later than the effective date of the Tier 3 final rule. 

Testing for RFG, CG, RBOB and CBOB batches: EPA proposes to allow monthly composites 

for winter RFG for aromatics, olefins, and distillation which is already allowed for Conventional 

batches. This is an example of a regulatory burden that is not needed to support out-of-date 

complex model standards. We propose that the requirement for aromatics, distillation, and 

olefins be eliminated completely for winter RFG and all Conventional batches. The effective 

date of this elimination should be no later than the effective date of the Tier 3 final rule. 

EPA states that the “values for aromatics, distillations and olefins may continue to be determined 

from monthly composites” for CG. We interpret “may” to mean a refiner has the discretion to 

test and report or not. We see no value to test and report aromatics, distillations and olefins for 

monthly composites of CG or CBOB for parties that are subject to MSAT2, not the anti-dumping 

toxics complex model. A clear elimination would result in a reduction in paperwork and 

reporting burden. The effective date of this elimination should be no later than the effective date 

of the Tier 3 final rule. 

We support the continuation of testing and reporting of all summer complex model parameters 

for summer RFG/RBOB batches because of the summer RFG VOC standard.

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

EPA is proposing to reduce the testing and reporting requirements for certain fuel parameters 

associated with the complex model. The Association supports the Agency’s efforts to eliminate 

regulatory obligations that are no longer needed. Such streamlining would reduce compliance 

costs and allow companies to focus more efficiently on more important aspects of compliance. 

IFTOA recommends that EPA adopt the proposed amendments to streamline testing and 

reporting obligations. 
Chapter 6: Regulatory Streamlining and Technical Amendments

6-4

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

Testing and Reporting of Fuel Parameters. EPA proposes to streamline the requirements for 

testing and reporting. Sutherland encourages all attempts at streamlining and simplifying the 

reporting requirements. Additionally, EPA should clarify whether it would like daily batch level 

production reports. 

Commenter: Marathon Petroleum Company LP (MPC)

EPA proposes to reduce the testing and reporting burden for individual batches of RFG and 

conventional gasoline (CG). Many of the tests for individual parameters are no longer needed 

because of the phase out of complex model standards. The complex model standard for NOx was 

replaced by the Tier 2 gasoline sulfur standard. The toxics complex model standard was replaced 

by MSAT2.30 The only remaining complex model standard for most refineries is summer RFG 

VOCs. 

We support the Agency’s proposal to eliminate API gravity. This is proposed to be effective on 

January 1, 2013 (see proposed 80.65(e)(3)). Given that the proposal was published in the Federal 

Register on May 21, 2013, this proposed effective date may be confusing because of its 

retroactive nature. Refiners recommend that the effective date remain January 1, 2013 in the final 

rule as it will be providing relief from a requirement. EPA should specify in the Preamble of the 

final rule that this will be retroactively applied. 

We support EPA’s proposal to eliminate testing and reporting for oxygenates (unless necessary 

because oxygenates added downstream are used in calculations). The effective date of this 

elimination should be no later than the effective date of the Tier 3 final rule. 

Testing for RFG, CG, RBOB and CBOB batches: EPA proposes to allow monthly composites 

for winter RFG for aromatics, olefins, and distillation which is already allowed for Conventional 

batches. This is an example of a regulatory burden that is not needed to support out-of-date 

complex model standards. We propose that the requirement for aromatics, distillation, and 

olefins be eliminated completely for winter RFG and all Conventional batches. The effective 

date of this elimination should be no later than the effective date of the Tier 3 final rule. 

EPA states that the “values for aromatics, distillations and olefins may continue to be determined 

from monthly composites” for CG. We interpret “may” to mean a refiner has the discretion to 

test and report or not. We see no value to test and report aromatics, distillations and olefins for 

monthly composites of CG or CBOB for parties that are subject to MSAT2, not the anti-dumping 

toxics complex model. A clear elimination would result in a reduction in paperwork and 

reporting burden. The effective date of this elimination should be no later than the effective date 

of the Tier 3 final rule. 

We support the continuation of testing and reporting of all summer complex model parameters 

for summer RFG/RBOB batches because of the summer RFG VOC standard. 
Tier 3 Summary and Analysis of Comments

6-5

Commenter: Phillips 66 Company

- Sampling and testing of fuel properties - We agree with the proposed elimination to test and 

report API gravity. Although EPA has proposed other modifications to potentially reduce the 

sampling and testing burden, we think the proposal does not go far enough. Currently, the 

complex model is only used to certify VOC controlled reformulated gasoline. Therefore, the full 

slate of properties that must be analyzed and input into the model for calculation of VOC 

emission reductions should only be required for reformulated gasoline or RBOB designated as 

VOC controlled. There should be no requirement to test conventional gasoline or non-VOC 

controlled reformulated gasoline or RBOB for olefins, aromatics, and distillation. This change 

would significantly reduce the laboratory testing burden and should be implemented effective 

upon promulgation of the final rule. 

Commenter: Shell Oil Products for Shell and Motiva

The preamble, under the Reporting Requirements section, 78 Fed. Reg. 29942, proposes 

denatured fuel ethanol batch reports to include properties and volume effective January 1, 2017. 

It is suggested that 40 CFR 80.1451 be amended to include the requirements of this additional 

reporting and 40CFR 80.1464 be amended to include attestation engagement procedures for this 

additional reporting. In this way, there is consistency with both ethanol and gasoline batch 

reports on how they are reported and attested. 

Our Response:

We are streamlining and reducing the reformulated gasoline (RFG) and conventional 

gasoline (CG) testing and reporting burden of gasoline refiners and importers by reducing the 

testing and reporting requirements of certain fuel parameters associated with the complex model. 

With the phasing out of complex model standards1, reduced testing and reporting is appropriate, 

particularly for RFG. In cases where a refiner is subject to only benzene, RVP, and sulfur 

standards, certain parameters no longer need to be tested and reported on an every-batch basis. 

However, refiners producing RFG during the summer volatile organic compound (VOC) control 

season will still need to use the complex model to determine VOC performance, and thus must 

still measure and report the relevant complex model fuel parameters. Sulfur and benzene will 

continue to be tested and reported on an every batch basis as these values are necessary for the 

Tier 2 and Tier 3 gasoline sulfur and MSAT2 benzene programs. In addition, small refiners that 

are subject to the delayed compliance option for the 0.62 volume percent benzene standard will 

have to use the complex model (and thus measure all complex model parameters) until 2015 for 

CG MSAT1 compliance.2

Currently, there are 17 complex model parameters on the RFG/anti-dumping batch 

report. We are reducing testing and reporting requirements for some of these parameters for 

RFG, CG or both in this final rule. All other reporting requirements not changed by the final rule 

 

1

Per §§80.41(e) and (f), and §80.101(c), applicable NOx and toxics emissions requirements are superseded by the 

Tier 2 gasoline sulfur standards and MSAT2 benzene standards, respectively. 

2

61 FR 17230 (March 29, 2001).
Chapter 6: Regulatory Streamlining and Technical Amendments

6-6

are still in effect. For both RFG and CG, we are eliminating testing and reporting of American 

Petroleum Institute (API) gravity. Regarding the effective date for this change, we have applied 

it retroactively in keeping with the proposed date. In addition, we are finalizing reporting 

requirements for refiners that either have gasoline containing oxygenates or that include

oxygenates added downstream in compliance calculations. 

For winter RFG, we are eliminating the requirement to test and report aromatics, 

distillations and olefins on an every batch basis and instead are allowing testing and reporting of 

monthly composites. Commenters from the refining industry strongly suggested that we 

eliminate testing of these parameters altogether, since they are not needed, and their elimination 

would further reduce the burden on regulated parties. While we agree that a reduction in burden 

would occur if refiners were not required to test, even on a monthly composite basis, for these 

parameters, the many interconnected aspects of the RFG program make any seemingly 

innocuous change potentially fraught with unintended consequences. Thus, we are will evaluate 

completely eliminating the testing of these parameters in any future fuel program restructuring.

In the proposal, we stated “...values for aromatics, olefins, and distillation terms may 

continue to be determined from monthly composites.” Some commenters viewed the term 

“may” in that sentence as meaning that reporting for those parameters is optional. That is an 

incorrect interpretation. In this final rule, we are finalizing requirements for use of either 

monthly composites or batch testing. The parameters must still be measured and reported. 

Commenters in the refining industry do not think these parameters need to be measured at all for 

parties subject to the MSAT2 benzene standard, as compliance with that standard is not 

dependent on aromatic, olefin, or distillation values. As mentioned earlier, there are several areas 

of the RFG and/or anti-dumping programs where testing and reporting burden could likely be 

reduced; however, we have not fully evaluated the implications of changing the current 

requirements, and thus we are leaving consideration of such changes to a future broader program 

restructuring.

6.1.1.2. De Minimis Threshold for Batch Volumes

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

We agree with EPA’s concept of a de minimis value, below which a party would not be required 

to correct and resubmit their batch reports. However, the proposed level is of little practical 

value. 

We suggest that a de minimis threshold value of 0.5 percent of any batch is a practical level that 

will provide the intended relief for regulated parties but will still sufficiently protect the integrity 

of EPA reporting and compliance programs. 

We agree with the concept of including a de minimis value for reporting of batch volumes, 

below which a party would not be required to correct and resubmit their batch reports. However, 
Tier 3 Summary and Analysis of Comments

6-7

the proposed de minimis level of the lesser of 500 gallons or 1 percent of the true batch volume 

is so small that it is of little practical value. A de minimis volume of 500 gallons is equivalent to 

approximately 12 barrels and will almost always be less that 1 percent of the true batch volume. 

For example, on a typical pipeline batch volume of 25,000 barrels, the 500 gallon de minimis 

volume represents approximately 0.05 percent of the total volume. On a large refinery 

production batch of 250,000 barrels, the de minimis volume of 500 gallons represents 

approximately 0.005 percent of the total volume. Such a small threshold value would fail to 

provide the intended relief and would not prevent a party from having to make inconsequential 

volume corrections. 

We suggest that a de minimis threshold value of 0.5 percent be applied regardless of batch size. 

Individual batch volumes that fall within plus or minus 0.5 percent (+/- 0.005 expressed as a 

decimal) of the true volume would not need to be corrected. The 0.5 percent de minimis value is 

a practical level that will provide the intended relief for regulated parties but will still sufficiently 

protect the integrity of EPA reporting and compliance programs. 

Regarding the impact of de minimis batch volume corrections on compliance with the benzene, 

sulfur, RFG, RFS and other Clean Air Act fuel standards, we recommend that EPA should delete 

the regulatory text at 80.10 (c) and 80.10(d). The application of a de minimis threshold implies 

that the small volume errors in batch reporting are truly inconsequential and do not have an 

impact on compliance with fuel standards. Therefore, no separate demonstration of material 

impact should be required. The normal, unintentional variation in batch volumes will be 

distributed both greater than and less than the true volume. These variations will cancel each 

other over time and do not represent any degradation of the standard. 

Commenter: Chevron Products Company; Marathon Petroleum Company LP (MPC)

We agree with the concept of including a de minimis value for reporting of batch volumes, 

below which a party would not be required to correct and resubmit their batch reports. However, 

the proposed de minimis level of the lesser of 500 gallons or 1 percent of the true batch volume 

is so small that it is of little practical value. A de minimis volume of 500 gallons is equivalent to 

approximately 12 barrels and will almost always be less that 1 percent of the true batch volume. 

For example, on a typical pipeline batch volume of 25,000 barrels, the 500 gallon de minimis 

volume represents approximately 0.05 percent of the total volume. On a large refinery 

production batch of 250,000 barrels, the de minimis volume of 500 gallons represents 

approximately 0.005 percent of the total volume. Such a small threshold value would fail to 

provide the intended relief and would not prevent a party from having to make inconsequential 

volume corrections.

We suggest that a de minimis threshold value of 0.5 percent be applied regardless of batch size. 

Individual batch volumes that fall within plus or minus 0.5 percent (+/- 0.005 expressed as a 

decimal) of the true volume would not need to be corrected. The 0.5 percent de minimis value is 

a practical level that will provide the intended relief for regulated parties but will still sufficiently 

protect the integrity of the EPA reporting and compliance programs.
Chapter 6: Regulatory Streamlining and Technical Amendments

6-8

Regarding the impact of de minimis batch volume corrections on compliance with the benzene, 

sulfur, RFG, RFS and other Clean Air Act fuel standards, we recommend that EPA should delete 

the regulatory text at 80.10(c) and 80.10(d). The application of a de minimis threshold implies 

that the small volume errors in batch reporting are truly inconsequential and do not have an 

impact on compliance with fuel standards. Therefore, no separate demonstration of material 

impact should be required. The normal, unintentional variation in batch volumes will be 

distributed both greater than and less than the true volume. These variations will cancel each 

other over time and do not represent any degradation of the standard.

Commenter: National Biodiesel Board (NBB)

NBB Opposes the Proposed Application of a “De Minimis” Correction to Obligated Parties 

Renewable Volume Obligations Under the Renewable Fuel Standard Program.

In the Tier 3 Proposal, EPA proposes new § 80.10, which would provide that obligated parties 

would not be required to “correct unintentional errors in reporting batch volume on previously 

submitted batch reports.” 78 Fed. Reg. at 30,003. With respect to the RFS2 program, this 

provision would apply “only to the volume of fuels produced or exported that result in a 

renewable volume obligation under subpart M.” Id. The Tier 3 Proposal’s entire explanation for 

this provision is one paragraph and is as follows: We are proposing for the correction of batch 

volume reports to allow for de minimis changes in reporting compliance that would not require a 

complete resubmission of compliance reports when a minor discrepancy of a few barrels is 

uncovered. This allowance for the correction of batch volume reports would apply to reporting 

for: RFG, anti-dumping, gasoline and diesel sulfur, MSAT2 and the RFS renewable volume 

obligation (RVO) (for RFS, this would only apply to the volume of fuels produced or exported 

that result in a RVO for obligated parties). We are proposing a new section 80.10 to define de 

minimis, for the purpose of this allowance, as no more than 500 gallons or by no more than 1 

percent of the true batch volume in gallons, whichever value is less. We request comment on 

whether or not a different amount would be more appropriate. 

Id. at 29,952. This one paragraph buried in a 377-page proposal is wholly insufficient for the 

public to meaningfully comment. NBB opposes the application of any so-called “de minimis” 

corrections to reporting renewable volume obligations. 

In the RFS2 program, Congress “directed” EPA “to ensure that transportation fuel sold or 

introduced into commerce in the United States . . ., on an average annual basis, contains at least 

the applicable volume of renewable fuel, advanced biofuel, cellulosic biofuel, biomass-based 

diesel” under the statute. NPRA v. EPA, 630 F.3d 145, 147 (D.C. Cir. 2010), reh’g denied, 643 

F.3d 958 (D.C. Cir. 2011), cert. denied, 132 S. Ct. 571 (2011); see also 42 U.S.C. § 

7545(o)(2)(A)(i), (iii), (o)(3)(B). Thus, EPA’s obligation is to enforce the statutory volumes. The 

means of enforcing the statutory volumes that EPA has established is through the annual 

renewable volume obligations for each obligated party. 

Unlike the other programs where the “de minimis” reporting correction may apply,1the RFS2 

program is a volume mandate and compliance is contingent on the actual volume of gasoline or 

diesel fuel produced or imported. While the Tier 3 Proposal does not provide adequate 
Tier 3 Summary and Analysis of Comments

6-9

information as to how the correction would apply for the RFS2 program, on its face it would 

appear as though an obligated party can under-report its gasoline production and, thereby, reduce 

its renewable volume obligations. While EPA claims the volume is de minimis (500 gallons or 

no more than 1 percent of the true batch volume, whichever is less), EPA provides no 

explanation as to whether that means, for example, each shipment overseas or each batch of fuel 

produced. Even if the correction applies to the one time volume reported at the end of the year, 

each obligated party can do so, potentially resulting in significantly less RINs actually being 

required. This is in clear violation of EPA’s obligation to “ensure” the minimum volumes are 

met. While an agency may have certain inherent authority to provide for de minimis exemptions 

in certain statutory schemes, such authority is not available where there is “an ‘extraordinarily 

rigid’ statutory mandate,” as is the case here. See Sierra Club v. EPA, 705 F.3d 458, 468 (D.C. 

Cir. 2013) (citation omitted); see also Kentucky Waterways Alliance v. Johnson, 540 F.3d 466, 

491 (6th Cir. 2008) (recognizing such authority “is not an ability to depart from the statute . . .”) 

(quoting Ala. Power Co. v. Costle, 636 F.3d 323, 360 (D.C. Cir. 1979)). 

This de minimis “correction” would also appear to be yet another means to reduce the statutory 

volumes in a manner that is beyond EPA’s authority. The statute provides EPA with limited 

waiver authority, imposing stringent procedural and substantive criteria on when EPA can reduce 

the statutory mandates. See 42 U.S.C. § 7545(o)(7). In addition to the clear requirements that 

EPA ensure “at least” the applicable volumes of renewable fuel are sold, this limited authority 

evidences that Congress sought to restrict EPA’s authority to reduce the statutory volumes, and a 

“de minimis” error in reporting of gasoline or diesel fuel production or imports is not among the 

reasons EPA can use its authority. The Tier 3 Proposal provides no explanation for EPA’s 

authority to allow for such correction. Such an omission is likely because there is no such 

authority for EPA to do so. See Sierra Club v. Tennessee Valley Auth., 430 F.3d 1337, 1346-49 

(11th Cir. 2005) (finding Alabama’s 2% de minimis rule impermissibly modified requirements in 

State Implementation Plan without undergoing proper procedures). 

Further, the general rationale for providing de minimis exemptions is administrative burdens. See 

Sierra Club, 705 F.3d at 462 (citation omitted). While such administrative burdens may justify 

providing renewable fuel producers with a de minimis exemption for certain under-or overreporting of RIN generation, which does not appear to even be contemplated by EPA in the 

proposal, there is no such administrative burden with respect to obligated parties annual 

reporting of their renewable volume obligation. Nonetheless, EPA’s proposal is limited only to 

obligated parties with no discussion whatsoever as to the administrative burdens to support such 

an exemption. Thus, EPA has not (nor can it) meet its burden to show why this de minimis 

“correction” is necessary here. Kentucky Waterways Alliance, 540 F.3d at 491 (“Determination 

of when matters are truly de minimis naturally will turn on the assessment of particular 

circumstances, and the agency will bear the burden of making the required showing.”) (quoting 

Greenbaum v. EPA, 370 F.3d 527, 534 (6th Cir. 2004)). 

In fact, EPA cannot identify any administrative burden or need for such a “correction” 

allowance. Unlike the numerous calculations necessary for the RIN generation and transactions 

that a producer must undertake on a per batch basis, obligated parties and exporters are only 

required to submit an annual compliance report. Such report is required two months after the end 

of the year, and EPA does not explain why an obligated party or exporter cannot obtain accurate 
Chapter 6: Regulatory Streamlining and Technical Amendments

6-10

numbers for the volume of gasoline or diesel fuel it produced or imported within that time.2

Indeed, in this same proposal, EPA is proposing to extend the time for obligated parties to submit 

their compliance reports by another full month. EPA’s rationale for this extension is to give 

obligated parties more time to address volume discrepancies identified through “volumetric 

auditing.” 78 Fed. Reg. at 29,952. 

Because EPA failed to provide any legal or factual support for its proposal, it also should not be 

allowed to manufacture such support in any final rule. Even if responding to comments, EPA 

cannot circumvent the notice and comment requirements of the Clean Air Act and 

Administrative Procedure Act. The Clean Air Act requires EPA to provide notice of its proposed 

rule through a statement of its basis and purpose, and to give the public a meaningful opportunity 

to comment. 42 U.S.C. § 7607(d)(3), (4), (5); see also 5 U.S.C. § 553(b), incorporated by 

reference in 42 U.S.C. § 7607(d)(3) (requiring “reference to the legal authority under which the 

rule is proposed” and notice of “either the terms or substance of the proposed rule or a 

description of the subjects and issues involved”). “The significance of rulemaking cannot be 

underemphasized. It gives parties affected by a decision an opportunity to participate in the 

decision-making process and forces EPA to articulate the bases for its decisions.” Donner Hanna 

Coke Corp. v. Costle, 464 F. Supp. 1295, 1305 (W.D.N.Y. 1979) (citation omitted); see also 

Envtl. Integrity Project v. EPA, 425 F.3d 992, 996 (D.C. Cir. 2005) (“[N]otice requirements are 

designed (1) to ensure that agency regulations are tested via exposure to diverse public comment, 

(2) to ensure fairness to affected parties, and (3) to give affected parties an opportunity to 

develop evidence in the record to support their objections to the rule and thereby enhance the 

quality of judicial review.”) (citation omitted); Weyerhaeuser Co. v. Costle, 590 F.2d 1011, 1028 

(D.C. Cir. 1978) (Court will defer to agency “so long as we are assured that its promulgation 

process as a whole and in each of its major aspects provides a degree of public awareness, 

understanding, and participation commensurate with the complexity and intrusiveness of the 

resulting regulations.”) (citations omitted). Given EPA’s obligations under the RFS2 program 

and the apparent potential for the proposal to reduce the overall volumes actually required, it was 

incumbent on EPA to ensure that it provided adequate notice and a meaningful opportunity for 

the public to comment.

Commenter: Phillips 66 Company

De Minimis Reporting Changes – We are very appreciative that EPA has recognized this issue 

and proposed an allowance for de minimis volume errors and corrections. We strongly support 

the concept of a de minimis volume allowance. However, the de minimis level proposed is far 

too small to be of any utility. Fortunately, the systems in place to measure and report batch 

volumes are very efficient and accurate. Unfortunately, there are some instances where slight 

errors do occur. Currently when an error is discovered, no matter how small the volume

difference, it results in having to change the batch reports and resubmit with the corrected 

volumes. EPA has proposed a de minimis level of 500 gallons or 1% of the batch volume, 

whichever is less. Typical pipeline batch volumes are 25,000 barrels. A 500 gallon difference in 

a 25,000 barrel batch constitutes a 0.05% difference. 
Tier 3 Summary and Analysis of Comments

6-11

We suggest the de minimis level be set at 0.5% for each batch. No further action should be 

necessary such as recalculation of property averages with the uncorrected volumes versus the 

corrected volumes. These should be considered de minimis from all aspects.

Our Response:

We proposed that parties who submit batch reports would not be required to correct 

inconsequential errors in reporting batch volumes under certain conditions, the primary condition 

being that the discrepancy met the definition of “de minimis”, which as proposed, was an amount 

no greater than the smaller of 500 gallons or one (1) percent of the true batch volume. Under the 

proposal, regulated parties would no longer be required to provide a complete resubmission of a 

compliance report when a minor discrepancy of a few barrels was uncovered. We proposed that 

this new provision would apply to reporting for RFG, anti-dumping, gasoline and diesel sulfur, 

and MSAT2. We proposed that it would also apply to the RFS renewable volume obligation 

(RVO), but would only apply to the volume of fuels produced or exported that result in a RVO 

for obligated parties. 

We have decided not to finalize the proposed de minimis provisions at this time. One of 

the primary motivations for proposing the de minimis provision was to avoid the need for 

inconsequential corrections to production volumes that would have no impact on compliance 

with standards that rely on production volumes (e.g., average standards and RFS). Late changes 

to production volumes for whatever reason can necessitate simultaneous changes to compliance 

calculations that, if de minimis, would have no meaningful impact on compliance. However, as 

comments highlight, it is has proven difficult to set an acceptable de minimis threshold that can 

apply across all potential situations. Furthermore, the proposed provision focused only on 

volume corrections, but in reality our experience suggests that corrections often take place for 

other purposes such as data entry, coding, formating or other typographical errors – not only 

minor corrections to reported volume. We believe that adjusting reports for inconsistencies will 

become less burdensome, as EPA intends to transition all reporting to electronic reporting in the 

future. In addition, EPA received input from the regulated community about a de minimis 

provision specifically as it related to the RFS program. We are finalizing a one-month delay in 

the RFS reporting deadline, which we believe will provide obligated parties with more time to 

review and correct their records and reports, and help to minimize the need for late corrections. 

We will revisit the need for a de minimis threshold in the future if these changes prove 

insufficient.

6.1.1.3. Reporting Deadlines

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

EPA should eliminate quarterly reporting for the RFG/RBOB batch reports. Data for all summer 

RFG/RBOB batches should be submitted once year with the annual RFG VOC compliance 
Chapter 6: Regulatory Streamlining and Technical Amendments

6-12

report. The Agency has proposed, and we support, the elimination of aromatics, distillations, and 

olefins for winter RFG/RBOB. Therefore, there is no purpose served for the first and fourth 

quarters. In addition, there is no point in splitting up summer RFG/RBOB between the second 

and third quarters. 

We support EPA’s proposal to set the due date for all fuel annual compliance reports at March 

31. This extension will provide some flexibility for refining company personnel while having no 

impact on emissions, air quality or compliance with the standards. 

The Agency proposes a new due date for additional reporting for refiners blending butane with 

RFG or RBOB at 80.75(o), March 1. This should be revised to March 31 to conform with the 

uniform due date above. 

Commenter: Chevron Products Company

Chevron is very much in favor of EPA’s proposal to align reporting dates between the various 

Part 80 programs and appreciates the extension of fourth quarter and annual reporting deadlines 

to March 31. We recommend that EPA should extend the attest engagement deadlines by an 

additional month from May 31 to June 30 to allow sufficient time for the significant datagathering and back-and-forth communications required to complete those engagements. While it 

may be possible to begin some of this work ahead of the new reporting deadlines, it is much 

more effective to focus on the reporting itself before shifting to the attest activities. We believe 

that extending these annual deadlines will significantly reduce the risk of error and rework in 

annual compliance reporting. 

Commenter: Marathon Petroleum Company LP (MPC)

EPA should eliminate quarterly reporting for the RFG/RBOB batch reports. Data for all summer 

RFG/RBOB batches should be submitted once a year with the annual RFG VOC compliance 

report. The Agency has proposed, and we support, the elimination of aromatics, distillations, and 

olefins for winter RFG/RBOB. Therefore, there is no purpose served for the first and fourth 

quarters. In addition, there is no point in splitting up summer RFG/RBOB between the second 

and third quarters. 

We support EPA’s proposal to set the due date for all fuel annual compliance reports at March

31. This extension will provide some flexibility for refining company personnel while having no 

impact on emissions, air quality or compliance with the standards. 

The Agency proposes a new due date for additional reporting for refiners blending butane with 

RFG or RBOB at 80.75(o), March 1. This should be revised to March 31 to conform with the 

uniform due date above. 

Commenter: Phillips 66 Company
Tier 3 Summary and Analysis of Comments

6-13

Change in reporting dates – Overall, the concept of aligning the various reporting dates and 

being able to develop a unified and simplified reporting form is a good one. Providing additional 

time is beneficial. We appreciate the Agency providing this change. 

Commenter: Weaver and Tidwell LLP

Assuming the EPA implements the reporting deadline changes contemplated in the NPRM, 

Weaver suggests that the deadline for submission of the annual attest reports be extended by one 

month (June 30 following the end of the compliance year). The proposed change of the annual 

reporting date for gasoline and RFS reports from the last day of February to March 31 following 

the end of the compliance year, without a corresponding change in the due date for annual attest 

reports, shortens the period of time for conducting the required attest work by one month. 

Regulated parties are often subject to attest engagements at multiple facilities and for various 

activities that are all inter-related (i.e., gasoline refiner being subject to gasoline attest 

engagements [each applicable subpart], as well as an RFS attest engagement). Therefore, the 

attest engagements can take a substantial amount of time to complete. 

Weaver would like to emphasize the importance of the attest function in relation to compliance 

with the EPA’s fuels regulations as a whole. The EPA receives completed annual attest reports 

which, in many cases, reflect compliance with the regulations. However, in our experience, 

during the performance of the attest procedures, a myriad of reporting and compliance issues are 

frequently discovered that can be and are remediated by the regulated party prior to the 

completion of the attest engagement (hence, a “clean/cleaner” attest report is prepared and filed 

with the EPA). If not for the independent attest engagement, it is our belief that many of the 

issues unearthed and remedied as part of the attest would otherwise go unchecked and 

undiscovered, thus shifting an increased level of review, investigation, and enforcement burden 

to the EPA. Without sufficient time to find, research and resolve these errors, omissions, and 

other instances of non-compliance, the efficacy of the attest function is diluted. 

Commenter: Turner, Mason & Company

The change in the reporting date for the fourth quarter and annual reports could significantly 

impact those who report to the EPA under 40 CFR 79 & 80. The reporting deadline for those 

reports is being pushed back by a month to March 31. The reporting deadline for the first quarter 

of the year is being pushed back by one day to June 1. In contrast, the reporting deadline for 

attestation reports remains the same at May 31. 

Because entities tend to delay submission of their reports to the EPA until all activities have been 

completed, the time available to conduct an attestation under the current regulations is three 

months. Under the current reporting schedule, it is already difficult to obtain data, conduct the 

attestation, review the attestation with the affected party, revise the attestation based on 

additional information provided by the affected party, obtain management representation letter(s) 

signed by the responsible corporate officer, and produce the final attestation report within the 

three month timetable currently existing. 
Chapter 6: Regulatory Streamlining and Technical Amendments

6-14

It is our experience at Turner, Mason & company that those involved in generating and 

submitting reports to the EPA are the same people that provide data for the attestations. Based on 

these new reporting deadlines, the months of April and May will become even busier for them. 

Under the new reporting schedule, they will be preparing the first quarter reports simultaneously 

to providing data to the attester(s) because of the increased workload in the shorter timeframe for 

these workers, we expect an increase in reporting errors. Thus, we find that extending the 

deadline for attestation reports by a month to June 30 would provide a month of relatively lighter 

workload for those involved in the attestations and reduce the probability of reporting error.

Commenter: Shell Oil Products for Shell and Motiva

In regards to Amendments Related to Reporting 78 Fed. Reg. 29949, we concur with the 

proposal to adjust and be consistent with reporting dates for various EPA programs. However, 

with the annual reporting date being moved from February 28 to March 31, the attestation 

engagement reporting date needs to be adjusted also. Currently, the attestation engagement report 

is due May 31 and we recommend the due date be changed to June 30 in order to continue to 

provide 3 months between the due dates of the annual report and the attestation engagement 

report. As proposed, a timeframe of two months between the annual report due date and 

attestation engagement report due date is too short of a time period.

Our Response:

In the final rule, EPA is amending various provisions to reduce the number of different 

reporting deadlines that regulated parties must meet and to enable the future use of a unified and 

simplified reporting form. Currently under 40 CFR parts 79 and 80, there are ten separate 

cyclical reporting dates each year (eleven in a leap year). Streamlining reporting deadlines will 

allow EPA to develop a single, user-friendly, electronic form that will collect all required data, 

maximizing the capability of electronic reporting to provide reuse of data and avoid duplicate 

data submission. EPA’s goal is to simplify reporting and reduce the number of hours parties 

spend preparing and submitting reports while simultaneously improving data received from 

stakeholders. This overall effort responds to Executive Orders 13563 and 13610, which direct 

government agencies to simplify rules and to achieve reductions in paperwork and reporting 

burdens, and is part of EPA’s agency-wide effort to streamline regulatory reporting 

requirements.

We are amending these deadlines so that all affected programs use the same four 

reporting deadlines. Programs that will be affected by this change include: 

the fuels and fuel additives registration program (40 CFR part 79, subpart A);

the Reformulated Gasoline and Anti-Dumping program (40 CFR part 80, subparts D and 

E);

the Gasoline Sulfur program (40 CFR part 80 subpart H);

the Motor Vehicle, Nonroad, Locomotive, and Marine Diesel program (40 CFR part 80 

subpart I);

the Gasoline Benzene program (40 CFR part 80 subpart L);

the Renewable Fuel Standard program (40 CFR part 80 subparts K and M); and

the Tier 3 program being finalized today (40 CFR part 80 subpart O). 
Tier 3 Summary and Analysis of Comments

6-15

Consistent with the proposal, we are finalizing that reporting deadlines will be 

standardized as follows: June 1, for all reports covering quarter 1 of the compliance year 

(January through March); September 1, for quarter 2 (April through June); December 1, for 

quarter 3 (July through September); and March 31 for quarter 4 (October through December). 

End-of-year compliance reports will also be due on March 31. These changes will either delay or 

maintain current deadlines for nearly all required reports. Deadlines for all other annual reports 

will either be maintained if they matched the new quarterly deadline, or extended to match the 

new quarterly deadline. It should be noted that even with the changes finalized today, 

respondents will still have the option to report earlier than any given deadline. Some 

commenters in the refining industry suggested eliminating all quarterly reporting for RFG if 

winter aromatics, olefins and distillation are no longer required to be reported as they suggested. 

These values are normally reported in the 1st and 4th quarters. As one commenter stated, “In 

addition, there is no point in splitting up summer RFG/RBOB reporting between the 2nd and 3rd

quarters.” We disagree. As noted above, winter aromatics, olefins and distillation are still 

required to be reported, albeit on a monthly composite basis. Thus, the need for quarterly 

reporting remains. However, we expect that the need for quarterly reports will be evaluated as 

part of a future broader program restructuring. 

EPA proposed not to include “Attest Engagements” (currently due May 31 of the 

following year) or reporting related to specific events under the Fuels Program, such as trading 

Renewable Identification Numbers (RINs) in EPA’s Moderated Transaction System (EMTS), in 

the reporting revisions described above. Rather, all reporting deadlines for Attest Engagements 

and reporting specific events will remain the same. Some commenters suggested that if the 

annual and fourth quarter reporting deadlines were to be extended to March 31 of each year, then 

the attest engagement date should also be shifted one month from May 31 to June 30 to allow 

sufficient time for the significant data-gathering and communications required to complete those 

engagements. EPA is not changing the compliance period associated with the new extended 

reporting date, but rather, is simply allowing additional time for data review, preparation and 

reporting. EPA does not believe that extending the attest engagement date is necessary because 

companies have the flexibility to use the extra reporting time to begin preparation for the attest 

engagement if they prefer. As stated previously, the extension to reporting deadlines does not 

preclude stakeholders from reporting before the deadline. EPA is not extending the date for 

attest engagements from May 31 to June 30. That said, EPA is streamlining reporting dates to 

aid in our development of a single electronic reporting format and is updating the due date for 

attest engagements found in part 80 from May 31 to June 1. This change will not affect 

compliance or increase burden of reporting entities. Rather, the purpose of streamlining various 

reporting deadlines is to ease reporting burden and help aid EPA in the development and 

implementation of a single electronic reporting format.

6.1.1.4. Previously Certified Gasoline (PCG)

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 
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Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

The Tier 3 proposal includes amendments for Previously Certified Gasoline. We support the 

proposed changes at 80.1235(a)(6) and 80.1347(a)(6). 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

Under current regulations, when refiners and importers are blending gasoline with Previously 

Certified Gasoline (“PCG”), they must test (1) the PCG for benzene before addition of the 

blendstock, (2) test the combined blend of PCG and blendstock for benzene, (3) calculate the 

properties of the blendstock by treating the PCG as a negative volume batch, and (4) treat the 

blended product as a positive batch. As EPA properly recognizes, due to variability in the 

benzene test method, this approach can, at times, result in calculated blendstock benzene 

concentrations that are negative, which is physically impossible. Therefore, EPA is proposing an 

alternative that would allow greater flexibility. EPA would amend the regulations to permit 

refiners and importers to sample and test each batch of the blendstock directly, and treat the 

blendstock as the produced batch for blendstock that is blended into PCG. This approach is very 

sensible and would eliminate illogical test results that have occurred in the field. 

IFTOA recommends that EPA adopt the alternative test method that has been proposed. It would 

provide a far more accurate test result and allow for more practical compliance. 

Our Response:

Consistent with the proposal, for blendstock that is blended into previously certified 

gasoline (PCG), we are finalizing an alternative requirement that allows refiners to directly 

sample and test each batch of blendstock, and treat the blendstock as a produced batch. We note 

that this practice is already allowed under the Tier 2 sulfur program.

6.1.1.5. Imports by Truck

What Commenters Said:

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

Under current regulations, when conventional gasoline is imported into the United States by 

truck, compliance with fuel parameters may be demonstrated by testing fuel in the storage tank 

from which the trucks are loaded. See 40 CFR Part 80, Subpart E, Section 80.101(i)(1) and (3).

However, pursuant to 40 CFR Part 80, Subpart L, Section 80.1347, each batch of gasoline 

produced or imported (RFG or conventional gasoline) must be sampled and tested for 

compliance with the benzene standard. The inconsistency of these two regulations has resulted 

in importers spending thousands of dollars testing each truck that enters the United States and 

this additional testing – testing each truck versus testing the tank from which the trucks are 

loaded – is unnecessary. It provides no greater testing accuracy and is so costly that it has a 

chilling effect on truck imports. Therefore, the Association welcomes the EPA’s proposal to 
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make the regulations consistent and allow gasoline imported into the U.S. by truck to 

demonstrate compliance by testing the gasoline in the storage tank from which the trucks are 

loaded. 

IFTOA endorses EPA’s proposal to allow gasoline imports made by truck to demonstrate 

compliance with applicable fuel parameters by testing the gasoline in the tank from which the 

trucks are loaded in accordance with the requirements set forth in 40 CFR Part 80, Subpart E.

Commenter: Irving Oil Terminals Inc.

EPA has proposed to allow entities that import conventional gasoline into the United States by 

truck to demonstrate compliance by following the sampling and testing requirements in Subpart 

E — sampling and testing of the storage tank that feeds the truck imports — as an alternative to 

the sampling and testing requirements of Subpart L that some have interpreted to require the 

testing of every truckload. Irving Oil strongly supports this amendment and commends the EPA 

for allowing importers to use a practical and more economic means of testing that provides the 

same degree of accuracy and makes the provisions in Subpart E and Subpart L consistent.

Our Response:

We are allowing importers who import gasoline into the United States by truck to use the 

sampling and testing requirements in subpart E for truck importers as an alternative to the 

sampling and testing requirements in subpart L. EPA provided these alternative requirements in 

subpart E to eliminate the need to test every truckload of imported conventional gasoline for all 

complex model parameters, including benzene. Since Subpart L also requires importers to test 

every truckload of imported gasoline for benzene, EPA believes it is appropriate to allow truck 

importers of gasoline to use the sampling and testing requirements in subpart E as an alternative.

6.1.1.6. Diesel Tech Amendments

What Commenters Said:

Commenter: Chevron Products Company

Diesel Pump Labels: Chevron supports the removal of the requirement for diesel fuel pump 

labels for 15 ppm highway diesel fuel. We do not expect that this will cause confusion for 

consumers and agree with EPA’s assertion that voluntary labeling is always an option for retail 

and wholesale facilities should that become an issue. It should be noted that §80.572(a) already 

contains an expiration date for these labeling requirements. The current regulations show an 

expiration date of September 31 [sic], 2014 and the amendment proposed in this rulemaking is 

actually extending the expiration date to November 30, 2014. There appears to be no reason for 

any extension and we assume this is an error. As EPA states in its preamble, these labels have 

been unnecessary since December 1, 2010. Therefore, an immediate removal of the requirement 

would be entirely appropriate. 
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Should the labeling requirements remain in place, we oppose the regulatory changes proposed 

that do nothing but underline the words ‘prohibits’ and ‘required’ in the current labeling 

requirements. If this requires that existing labels, which are no longer required after 2014, be 

updated, it’s an expensive and burdensome proposition with little tangible benefit. 

Commenter: Magellan Midstream Partners, L.P.

Transmix exemption — EPA has proposed per-gallon and marker requirements for NRLM diesel 

fuel, ECA marine fuel, and heating oil downstream of the refiner or importer. EPA has also 

clarified that this provision does not apply to LM diesel fuel produced from transmix or interface 

fuel that is sold or intended for sale in areas other than those listed in §80.510(g)(1) or (g)(2), as 

provided by §80.513(f). 

Magellan Comment — we agree with EPA on the transmix exemption and strongly encourage 

the agency to adopt this provision. The high levels of sulfur in jet fuel create challenges for 

transmix processor because access to certain markets has been restricted. 

Our Response:

We are removing the requirement for diesel fuel pump labels for 15 ppm highway diesel 

fuel. Beginning December 1, 2010, all highway diesel fuel was required to be 15 ppm or less; 

thus, highway diesel fuel labels are no longer needed to distinguish it from 500 ppm highway 

diesel fuel. However, we do recognize that it may confuse consumers who are accustomed to 

seeing the highway diesel fuel pump labels if those labels were to disappear, thus, retail and 

wholesale purchaser-consumer facilities will be free to continue labeling to eliminate confusion 

if they so choose. The elimination of this requirement from the regulations does not preclude 

retail and wholesale purchaser-consumer facilities from keeping 15 ppm highway diesel fuel 

pump labels, it only eliminates the EPA requirement that such labels must be present. 

We are finalizing the proposed change to §80.511.

6.1.1.7. Test Method Updates

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Amendments to Update Test Methods: We note that, in some instances, the test method which 

EPA is proposing to update in this rulemaking does not necessarily represent the most recent 

version adopted by ASTM International. For instance, the proposal references ASTM D4057-06 

(2011) the manual sampling standard practice for petroleum and petroleum products. However, 

this standard practice was significantly revised and was recently re-issued as ASTM D4057-12. 

We strongly urge EPA to update its test method references to the most current versions available 

when it publishes the final rule, or, at the very least, provide a rationale for not doing so. 
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Commenter: Chevron Products Company

Test Method Reporting: Numerous updates are proposed to add the requirement that test 

methods be reported whenever fuel properties are reported under existing programs. 

Understanding that this is intended to enable the Performance Based Measurement System, we 

urge the EPA to consider how best to simplify the adoption of this requirement in its reporting 

procedures. Adding a test method field corresponding to every property field on existing report 

forms would greatly increase the size and complexity of those forms and, where the PBMS is not 

employed, would add no value. We recommend allowing obligated parties to report standard test 

methods in one separate notification and indicate exceptions, if any, separately.

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

In the Preamble that accompanied the proposed rules, EPA explained that refiners, importers and 

oxygenate blenders producing gasoline and diesel are required to test various fuel parameters. In 

a number of the regulations, there are references to test methods that have been revised or 

updated since the regulation was adopted. Therefore, EPA is proposing to amend the regulations 

and to reflect the new or updated ASTM test methods. 

The Association supports the basic concept of the proposal – updating test methods. However, 

the Association believes that the regulations should be amended to authorize refiners, importers 

and oxygenate blenders to use the current version of the test method at the time of the testing –

not one current at the time the final rule is adopted. In this way, industry would be employing 

methods that ASTM deemed appropriate and would facilitate better operation for the user of the 

test method. In addition, EPA should retain those alternative test methods it has already 

approved for use. 

Recommendation: The Association supports EPA’s efforts to reference updated/revised test 

methods in the regulations used to test gasoline and diesel fuel parameters. However, the 

Association recommends that EPA go further with its amendment and authorize testing using the 

current version of the applicable test method as of the date of testing or an alternative test 

method approved by EPA. 

Organization:Irving Oil Terminals Inc.

Irving Oil supports the updating of test methods used for various fuel parameters and also 

recommends that the regulation require compliance to ‘the most current version of each method’

instead of specifying a revision status date. This would allow the EPA and industry to perform 

testing by responding with the most current technology available.

Commenter: Phillips 66 Company

Update Test Method references - We support the proposal to update the referenced test methods 

to more current versions but ask that EPA check for the most current versions. 

Our Response:
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Refiners, importers and oxygenate blenders producing gasoline and diesel motor vehicle 

fuel are required to test RFG, CG and diesel fuel for various fuel parameters including aromatics, 

benzene, distillation, olefins, oxygenate content, RVP, and sulfur. As stated in the proposal, a 

number of relevant regulatory provisions had references to test methods that have been revised 

and updated. Several comments were received indicating that since the time of the proposal, 

some of the proposed updates have been further revised and updated and the desire was 

expressed for the regulated community to have the opportunity to use the most current version of 

each of these test methods. Consistent with the proposal, in this final rule we are updating those 

test methods to reflect current test methods in order to ensure that all test methods are readily 

available to the regulated community. (See Section VI.A.1.c of the preamble to the final rule and 

more specifically Table VI-2 for the list of test methods.)

6.1.1.8. Broader Regulatory Streamlining

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

There are additional topics that should be included in regulatory streamlining. Some are very 

simple and straightforward and should be implemented quickly and easily. These were suggested 

to EPA by API and AFPM in a memo sent to EPA on May 11, 2011 (Attachment No. 2). 

Although EPA addressed a few suggestions, the following issues remain.

MSAT2:

§80.1347(a)(3) requires that each batch of gasoline be sampled and tested for benzene content. 

Refiners are required to test each batch at a significant expense. The cost of a single benzene test 

ranges between $130 and $350, a cost which becomes disproportionate for small volume 

blenders. For all gasoline this program imposes averaging standards rather than any per-gallon 

limits. Allowing the individual batch samples to be composited prior to analysis would reduce 

costs and simplify reporting and recordkeeping. 

Batch reports and the addition of oxygenates to CBOB:

In section 80.69, EPA describes an alternate QA program for RBOB to confirm that the proper 

amount of ethanol is being added to the RBOB. That confirmation essentially enables the 

refiners to account for the 10% dilution of sulfur and benzene in their batch reporting. The 

alternate QA program addresses the situation where the RBOB is distributed through a fungible 

pipeline system like the one that serves the Mid-Atlantic and northeast states. If a refiner wants 

to account for the ethanol dilution for conventional gasoline via fungible shipments of CBOB, 

there is no parallel QA program allowed and EPA has declined to clearly indicate the RBOB 

approach for CBOB is acceptable. EPA should revisit and clarify to allow the same survey 

approach used for RBOB to apply to CBOB distribution systems, as well. EPA should allow 

refiners to account for the ethanol dilution for conventional gasoline via shipments of CBOB. 
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Under 40 CFR 80.101(d)(4), EPA Anti-Dumping regulations require a refiner or importer to 

include in its compliance calculations any conventional gasoline blendstock (CBOB) that is 

produced or imported which becomes conventional gasoline solely upon the addition of 

oxygenate. Refiners and importers must conduct a program of quality assurance testing at the 

downstream oxygenate blending facility in order to include the oxygenate in their compliance 

calculations. Under the current regulations, refiners must conduct a program of sampling and 

testing (quality assurance) at the downstream oxygenate blending facility in order to include the 

oxygenate in their compliance calculations. This rule provides an alternative QA requirement for 

these refiners and importers. 

When oxygenate is to be added to produce a finished conventional gasoline at a downstream 

oxygenate blending facility, refiners produce a product called conventional gasoline blendstock 

for oxygenate blending, or CBOB. CBOB is certified by the refiner, or by an importer who 

imports CBOB, as complying with all of the conventional gasoline requirements. The oxygenate 

blender is responsible for complying with the oxygen requirement when the oxygenate is added 

to the CBOB to produce a finished conventional gasoline at the oxygenate blending facility. 

Oxygenates such as ethanol, have a propensity to attract water, and, as a result, cannot be added

at the refinery, particularly where the finished gasoline will be shipped through a fungible 

pipeline on its way to terminals and retail gasoline stations. As a result, CBOB is typically 

produced for blending with ethanol at a blending facility downstream from the refinery that 

produced the CBOB.

Where a specific type and amount of oxygenate is designated for CBOB, the regulations require 

the refiner or importer to conduct downstream oversight sampling and testing quality assurance 

(QA) of the downstream oxygenate blending facility (40 CFR 101(d)(2)). This is to ensure that 

the specific type and amount of oxygenate that is designated and claimed by the refinery or 

importer for compliance, is in fact added to the CBOB by the oxygenate blender. In addition, the 

refiner or importer must have a contract with the oxygenate blender which requires the blender to 

comply with the blending procedures specified by the CBOB refiner or importer and allows the 

refiner or importer to conduct the required QA sampling and testing (40 CFR 80.101(d)(1)). If 

the refiner or importer does not meet the contractual and quality assurance requirements for 

CBOB, the refiner or importer may not include the oxygenate for compliance purposes.

Due to the complexities of the gasoline distribution system, it would be extremely difficult, if not 

impossible, to track CBOB from the refinery where it was produced to the terminal where it was 

blended with ethanol in order to comply with the downstream QA sampling and testing 

requirements specified in the regulations. In order to facilitate ethanol blending, effective August 

1, 2006, EPA amended the RFG regulations to permit refiners and importers seeking to add 

ethanol to RBOB an alternative quality assurance and downstream sampling and testing 

program. This program needs to be extended to refiners and importers supplying CBOB for 

downstream oxygenate blending in conventional gasoline areas as well.

RFG Sections 80.68 and 80.79:

Section 80.79 addresses liability for violations and addresses the defense elements which must be 

present. One of those defense elements is that the refiner must have a QA program at each of the 

points in a distribution system, excepting the truck carrier. Section 80.68 covers the need for 
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retail surveys, surveys which are conducted by the RFG Survey Association for their members. 

A Q&A that dates back to the mid-nineties is as follows: 16. Question: May survey samples be 

used as a substitute for a refiner’s quality assurance program for enforcement purposes? Answer: 

Surveys may not be used as a substitute for a regulated party’s own quality assurance program. 

Industry has been conducting independent surveys of their retail sites whereas they should be 

allowed to rely on the RFG Survey Association survey samples of individual brands. 

Commenter: Chevron Products Company 

Regulatory Streamlining General Requirements and Deadlines: Chevron supports the reduced 

reporting requirements for reformulated gasoline and EPA’s focus on simplifying reporting to 

those elements critical to compliance. We strongly encourage EPA’s notion of performing a 

comprehensive restructuring of the Part 79 and 80 regulations to improve comprehension, reduce 

compliance costs and simplify reporting. Identifying all of the various opportunities for 

consolidation and simplification would go well beyond the timing and scope of this rulemaking 

but we encourage EPA to immediately form a working group with industry representatives to 

pursue a follow-up rulemaking with the goal of proposing regulatory updates by the first quarter 

of 2014. 

Commenter: Irving Oil Terminals Inc.

Certification of Fuels (RFG and CG) and Commingling: EPA has asked for comments on the 

need to revise the regulations surrounding RFG and conventional gasoline relating to such issues 

as areas of sale and commingling of product. Irving Oil supports efforts to streamline the 

regulations and had anticipated proposals to address these issues. There are at least two reasons 

to move forward with such revisions. 

First, there have been several times when Irving Oil has had gasoline certified as conventional 

gasoline that meets the specifications/requirements for RFG. When an emergency occurred in a 

nearby RFG-market and there were shortages of product, Irving OH could have moved its 

conventional gasoline to the RFG area to alleviate the problem. However, it was prevented from 

doing so because it could not recertify the gasoline, even though it met the RFG standards and 

would not have adversely affected air quality. 

Second, at present, a company may not commingle RFG and conventional gasoline in the same 

tank. However, in those instances when gasoline meets both the RFG and conventional gasoline 

standards, use of commingled storage, coupled with robust recordkeeping, would substantially 

reduce costs and facilitate more effective operations. 

Commenter: Magellan Midstream Partners, L.P.

80.82 Sulfur Sampling Results at Time of Transfer:

Magellan Comment — The revised 40 CFR 80.82(i)(2)(iii) specifies that butane blenders must 

obtain a copy of the butane supplier’s test results at the time of each transfer of butane. This 

requirement is an unnecessary burden because the same test results often apply to multiple 

shipments of butane over the course of days or weeks. Rather than requiring redundant 
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6-23

conveyance of the same information, it should be adequate assurance to require that the blender 

obtain test results that represent each batch. Magellan proposes that 80.82(i)(2)(iii) be revised to 

include the following language: ‘The butane blender must obtain a copy of the supplier’s test 

results to represent each transfer of butane to the butane blender.’

80.1347(6) Benzene sampling upon receipt at refinery vs. refiner:

Magellan Comment — The revised 40 CFR 80.1347(a)(6) specifies that when sampling blend 

stock for benzene representation the refiner must take the sample when the blend stock is 

received at the refinery. We propose that the refiner should be allowed to take this representative 

sample upon receipt by the refiner, but that the sample need not be taken at the specific refinery 

where the blendstock is blended into previously certified gasoline. We propose changing the 

words ‘at the refinery’ to ‘by the refiner.’

As discussed in the recent call and in our comments to the proposed rule, Magellan strongly 

supports a revision to 80.1347 (a) (6) from ‘when it is received at the refinery’ to ‘when it is 

received by the refiner’. The reason for the modification is to allow for a gasoline blender to 

receive, sample, and test blend stock at a central company facility and then distribute that same 

blend stock to various other company owned refineries. This change would avoid the need to 

build blend stock storage at each refinery facility or to sample every truck load of blend stock 

blended at a location that did not have blend stock storage. Construction of dedicated blend stock 

storage at all facilities would be extremely expensive or in some cases is physically impossible 

due to space constraints and sampling of individual truck loads is logistically challenging and 

unduly expensive. An oversight program similar to that found in 80.82 could be implemented to 

ensure that blend stock quality is maintained during transport.

Commenter: National Biodiesel Board (NBB)

EPA Should Review and Conform the Various Product Transfer Document Requirements that 

May be Applicable to Biodiesel: In the Tier 3 Proposal, EPA notes that the fuel industry has 

requested EPA to review its Part 79 and Part 80 regulations to look for further ways to streamline 

the regulations. “EPA requests comments on potential areas in the fuel regulations that may 

benefit from such a more comprehensive streamlining effort.” 78 Fed. Reg. at 29,953. As NBB 

noted in its comments on the Quality Assurance Program proposal, see EPA-HQ-OAR-2012-

0621-0069 at 57-58, there are numerous disclosure requirements that must be included on 

product transfer documents for biodiesel blends, and NBB requests that EPA review and 

conform these requirements.

Biodiesel is subject to product transfer document requirements under the RFS2 program and the 

ultra-low sulfur diesel fuel program. This may be in addition to any state requirements as well. 

EPA should consider whether these statements can be consolidated to address the various 

regulatory programs without conflicting with potential state requirements. While the definitions 

for other diesel fuels may be different under the various programs, it is not for biodiesel. 

Biodiesel is fuel that meets ASTM D 6751. This is the standard that is applicable to biodiesel 

regardless of its use, although the finished fuel may be subject to another ASTM standard such 

as heating oil (ASTM D 396). There simply is little need for EPA to require long and 

overlapping statements on biodiesel product transfer documents. Thus, NBB recommends that 
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EPA require one statement that can cover these various requirements. For example, it should be 

sufficient to state that: “This volume of fuel is or contains biodiesel for which RINs have been 

generated under § 80.1426, is designated or intended for use as or in transportation fuel, heating 

oil or jet fuel.” For blends, EPA may also require disclosure of the sulfur content to ensure 

compliance with 40 C.F.R. § 80.590.

Commenter: Phillips 66 Company

Other Streamlining Issues – EPA has asked for comment on other provisions that we feel should 

be considered that would increase efficiency and reduce costs. There are several issues that the 

industry has discussed with EPA that we still feel should be pursued. In addition, Phillips 66 has 

internally identified an issue that we ask the Agency to consider. These are: 

CBOB – simplification of process to allow inclusion of ethanol blended downstream - The 

current process for RBOB certification and downstream quality assurance should be replicated 

for CBOB. Although there is a process in the regulations for capturing ethanol volumes blended 

into conventional gasoline or CBOB downstream, it is virtually impossible to utilize in situations 

where a refinery is shipping fuel on large fungible pipeline systems (such as Colonial Pipeline). 

Back in 2006, EPA finalized regulations that provide refiners an alternative quality assurance 

and downstream sampling and testing program for RBOB. This program needs to be replicated 

and extended to CBOB. The industry has previously done extensive work in looking at sections 

of the regulation and potential language changes necessary to provide this option. In addition, the 

RFG Survey Association has outlined a program to provide the quality assurance sampling and 

testing that would be required, similar to the current program for RBOB. Our industry could 

provide updated information to the Agency in an expedited manner for inclusion in this 

rulemaking. Currently, refineries have to test properties on CBOB or conventional gasoline on a 

clear basis for batch reporting purposes to EPA. However, they are also having to hand blend 

ethanol into the samples and test to assure the fuel will meet performance standards on a blended 

basis. Providing the requested regulatory change would simplify the laboratory sample handling 

and testing. 

Our Response:

Today’s rule also clarifies the list of products that are not to be included in a refinery’s or 

importer’s compliance determination under §80.1240. Refiners and importers are currently 

required under §80.1235(b)(2) to exclude oxygenate added to finished gasoline, RBOB or CBOB 

downstream of either the refinery that produced the gasoline or the import facility where the 

gasoline was imported. This conflicts with EPA’s intended approach in §80.1238(b), which 

allows refiners and importers to include oxygenate blended downstream of a refinery or import 

facility in their annual average benzene calculation, provided the refiner or importer meets 

certain requirements. We are finalizing changes that will allow refiners and importers to include 

oxygenate blended downstream of their facility and that will make these related sections 

consistent. EPA received significant support for this action from commenters. 

The current set of fuel regulations is the result of programs that have been established 

over the years to reduce emissions from mobile sources. These programs include gasoline 
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volatility (RVP), reformulated gasoline and anti-dumping, sulfur control (which today’s Tier 3 

program will revise), mobile source air toxics (MSAT1), benzene control (MSAT2), and the 

renewable fuel standards (RFS). Most of these regulations have been amended numerous times.

The RFG and anti-dumping regulations in particular contain some of the more extensive 

requirements on sampling, testing, and reporting. They also have some of the more stringent 

restrictions on gasoline use (e.g., restricting where fuel produced can be sold, what it may be 

commingled with, etc.). EPA used the RFG and anti-dumping rules as the foundation for many 

aspects of subsequently developed fuel regulatory programs. However, the subsequent rules, 

considered as a whole, have supplanted most of the RFG and anti-dumping standards. For this 

reason, we proposed to streamline the regulations in several places as described above. Initial 

discussions with fuel industry representatives have indicated that a comprehensive review of the 

complete set of fuel regulations contained in 40 CFR parts 79 and 80 (“Registration of Fuels and 

Fuel Additives” and “Regulation of Fuels and Fuel Additives,” respectively) could lead to further 

streamlining of the regulations beyond the streamlining provisions being finalized today. EPA 

expects that further streamlining would result in more efficient and less costly compliance 

determinations for affected parties while maintaining the environmental benefits of the programs. 

In many cases such changes could require not just the removal or streamlining of existing 

provisions but also the replacement of several provisions with new, less onerous ones that 

require further development, notice and comment. We intend to continue to seek comment in 

future actions on potential areas in the fuel regulations that may benefit from such a more 

comprehensive streamlining effort. For example, it may be possible for the RFG VOC standard 

to be met if a sufficiently stringent RVP level is attained. Under this scenario, sampling and 

testing requirements at the refinery would be reduced. Another potential scenario could involve 

consolidation of some RFG and anti-dumping rules; for example, a single set of rules governing 

the treatment of downstream ethanol blending and in-use surveys could provide greater 

efficiency and flexibility regarding fuel distribution.

We received a number of comments supporting the concept of further streamlining in 40 

CFR parts 79 and 80, including suggestions for additional areas of the regulations to consider in 

the future.

6.1.1.9. Other

Alternative Laboratory

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

We support the proposed changes at 80.65(f)(5) that would allow a facility to use an alternate 

independent laboratory. This will provide needed flexibility when there is an unexpected 

problem. 
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Commenter: Phillips 66 Company

Alternative designated lab – We support the proposed provision to allow designation of an 

alternative lab. There are occasions when the primary designated lab has an instrument outage or 

other problem preventing them from being able to complete the necessary sample analysis. 

Providing another option will alleviate these issues when they arise. 

Our Response: 

Refiners have indicated to EPA that significant problems are created when a facility’s 

designated lab is nonoperational and testing cannot be performed at the lab during that time 

period. We are thus finalizing (at §80.65(f)(5)) that a facility will have the ability to designate a 

back-up or alternative lab for testing during such times. In no case could this alternative lab be 

used to select the best test result, rather it may only be used on those occasions where operational 

necessity causes a need for it (e.g., the normal lab is closed, the apparatus for certain test 

methods are down, or independent lab personnel are not available). 

Responsible Corporate Officer

What Commenters Said:

Commenter: Phillips 66 Company

Changes needed in registration update procedures – Currently, any update to a company or 

facility registration requires signature from a responsible corporate officer (RCO) no matter the 

nature of the change. This process, which requires senior level approvals for relatively minor 

administrative updating, is very burdensome for executives and can be streamlined using 

sufficient company delegations. An example of this is a change in the facility contact 

information: a simple revision to a phone number requires RCO signature. We strongly 

encourage the EPA to provide flexibility in this process by granting authority to the RCO’s 

designated company editor to make these changes without requiring additional RCO signatures. 

Also, there should be a mechanism for an RCO to designate which notifications are directed to 

him/her directly or to specifically choose to have notifications go to his chosen editor instead. An 

example is the notifications that go out when reports are submitted or resubmitted. In the 

situation where the company has a significant number of facilities, these notifications add greatly 

to the RCOs e-mail load. Our company editor would be happy to work directly with the EPA to 

help outline some specific changes that would alleviate burden and frustration in this area. 

Our Response:

Regarding the suggestion that EPA revise the instances when a “responsible corporate 

officer” signature is required, we understand the concern expressed, but do not believe a 

regulatory action is necessary to address this concern. Rather, this issue is best addressed via 

administrative procedures. EPA plans to further evaluate this specific concern and similar 
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“responsible corporate officer” issues and address the concerns in the future, outside of the 

regulatory framework.

Diesel Cetane Number

What Commenters Said:

Commenter: Ford Motor Company (Ford)

Diesel – Need for Increased Market Fuel Cetane Number: Ford would like to take this 

opportunity to recommend the need to increase the minimum cetane number in typical diesel 

market fuel to the EPA’s attention for future regulatory action. 

A higher cetane number is preferred to support a shorter ignition delay and better ignition quality 

as these are important to achieving the stringent Tier 3 emission standards. An increase in cetane 

number generally results in decreased emissions of HC, CO, and NOx. Increased cetane number 

results in a slower rise in combustion pressure, which leads to lower gas temperatures and in turn 

reduces the formation of NOx. Low levels of in-use cetane rating can increase white smoke 

emissions during cold start and lower cetane ratings result in higher combustion noise - the low 

ignition quality of the fuel causes rapid burning of the larger amount of fuel injected before 

ignition occurs, which results in higher cylinder peak pressure and creates the characteristic 

diesel noise. Additionally, running an engine on diesel fuel with a lower cetane number than 

required will result in cold starting difficulties, reduced performance, and increased emissions. 

As a result of refineries optimized for maximum gasoline production, specified cetane levels are 

typically lower in North America than in Europe. In order to maintain the balance between the 

highest fuel economy and lowest emissions, diesel engines are designed based on fuels that are 

most representative of the market fuels where the vehicle will be sold. This makes it imperative 

for market fuel specifications to have tolerances that allow little variation in the fuel properties 

so that the engines will perform as close to the design standard as possible. The current ASTM 

D975 minimum cetane rating specified is too low to achieve maximum fuel economy and 

emissions improvements that are required in the near future. 

Recommendation: Ford supports raising the minimum cetane level to 51 in order to align with 

European Union (EU) specifications, which will foster diesel engine technology advancements in 

global product development. 

Our Response:

As noted by the commenter, this comment is outside the scope of the Tier 3 rule. If a 

future rule is promulgated regarding diesel cetane number, the commenter’s suggestion could be 

considered at such time.

6.1.1.10. RFS
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General

What Commenters Said:

Commenter: National Biodiesel Board (NBB)

While NBB appreciates the opportunity to comment on the proposed amendments to the RFS2 

program, it is concerned with EPA’s decision to make these proposals as part of an unrelated 

rulemaking and with insufficient explanation as to the legal authority or rationale supporting 

such changes. This is even more troubling given the extensive proposals on the RFS2 program 

that were recently made in the notices regarding the Quality Assurance Program and technical 

amendments. Thus, NBB requests EPA provide more explanation for the amendments, as 

required by the Clean Air Act, and a meaningful opportunity to comment on them.

Our Response:

We disagree with the comment. The Agency utilized the Tier 3 rulemaking to also 

propose and finalize a number of relatively minor regulatory streamlining actions cutting across 

our vehicle and fuel programs, including several that related to the renewable fuels program.

These actions were fully noticed in the proposal.

At proposal, we explained the need to revise and streamline certain provisions in order to

reduce the burden on industry or in other words to provide additional flexibility. We explained that 

these revisions would have no expected environmental impact. Specifically, we proposed changes 

to the RFS2 annual report date from the last day of February to March 31. EPA intended the 

change would 1) alleviate staffing problems for regulated entities because the regulatory 

requirements are often handled by the same personnel and 2) provide relief from the urgent need 

to obtain RINs when small discrepancies in gasoline production or import volumes are realized. 

We also explained that streamlining reporting dates would allow EPA to develop a single, userfriendly, electronic form that would collect all required data, maximizing the capability of 

electronic reporting to provide reuse of data and avoid duplicate data submission. Additionally, 

we sought comment on whether the same date extension from the last day of February to March 

31 should apply to those transferring RINs in EMTS for satisfying RVOs under the previous 

compliance year. We are not finalizing this change in this final rule, in response to comments. 

Further, EPA proposed not to include “Attest Engagements” (currently due May 31 of the following 

year) or reporting related to specific events under the Fuels Program, such as trading Renewable 

Identification Numbers (RINs) in EPA’s Moderated Transaction System (EMTS), in the reporting 

revisions described above. Rather, all reporting deadlines for Attest Engagements and reporting 

specific events will remain the same. Finally, we proposed that parties who submit batch reports 

would not be required to correct inconsequential errors in reporting batch volumes under certain 

conditions, the primary condition being that the discrepancy met the definition of “de minimis”, 

which as proposed, was an amount no greater than the smaller of 500 gallons or one (1) percent of 

the true batch volume. (See 78 FR 29950-29953). As discussed in Chapter 6.1.1.2 above, we are not 

finalizing any de minimis provisions at this time.
Tier 3 Summary and Analysis of Comments

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Reporting Dates

What Commenters Said:

Commenter: Chevron Products Company

In conjunction with the RFS compliance deadline, the ability to trade RINs in EMTS for 

satisfying previous year RVOs should be extended to March 31 as well to enable maximum 

compliance flexibility. An end-of-February cutoff date would mean a de facto end-of-February 

deadline to finalize compliance reporting given the potential need to purchase additional RINs 

for compliance. 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)

March 31 Annual Reporting Date and Trading: EPA is proposing to amend the annual reporting 

date for the Renewable Fuel Standard Program. Currently, compliance must be demonstrated by 

February 28 for the prior year. EPA is proposing to change that date to March 31. In addition, 

the Agency has asked for comments on whether trading of RINs used to demonstrate compliance 

should also continue through March 31. 

The Association supports the change to the annual reporting date, but believes that all trading of 

RINs to meet the prior year’s obligations should cease on February 28. In this way, members of 

the regulated community would have sufficient time to (a) calculate their precise RVOs for the 

prior year, (b) determine the volume of RINs held in inventory,(c) verify those RINs, and (d) 

prepare the reports in a timely manner. Separating the close of RIN trading from RIN reporting 

by a month should improve compliance and reporting accuracy. 

Recommendation: The Association supports the proposed change in the annual reporting date 

from February 28 to March 31, but opposes any change to the date when RIN trading ceases; the 

later should remain at February 28. 

Commenter: Irving Oil Terminals Inc.

Change in Annual Reporting Date — March 31: EPA has proposed to change the RFS2 annual 

reporting date from February 28 to March 31. EPA is also seeking comment on whether the 

ability to transfer RINs into the EMTS to meet an obligated party’s previous compliance year’s 

Renewable Volume Obligation (‘RVO’) should be extended to March 31 as well. Irving Oil 

supports the annual reporting change to March 31. However, it believes that the February 28 

deadline for RIN trading and meeting a company’s RVO should be retained. By allowing a 

month to elapse between the two activities, obligated parties have sufficient time to complete 

their accounting, verify their RVO and RIN inventory and work through their approval process 

with the Responsible Corporate Officer. This separation would facilitate more accurate reporting 

to EPA. 

Commenter: National Biodiesel Board (NBB)
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NBB Requests Clarification as to the Proposal to Amend the RFS2 Annual Report Date and 

Potential Implications for the RIN Market. In a purported attempt to address “a staffing problem” 

with respect to the RFS2 annual compliance reporting and reporting under other fuels programs, 

EPA is proposing to revise the annual compliance reporting date in 40 C.F.R. § 80.1451 for 

obligated parties from February 28 to March 31. 78 Fed. Reg. at 29,952. NBB does not 

necessarily oppose such an extension, but it is wholly unclear whether the proposal is truly 

addressing such a staffing issue and, thus, is necessary. In particular, EPA cites the RFG and 

anti-dumping compliance deadlines, but EPA is also proposing to move several of those 

February 28 due dates to March 31. See id. at 30,012, 30,015. NBB requests clarification as to 

EPA’s rationale for the need to move the dates. 

EPA also contends that the extension will allow obligated parties to conduct a “volumetric 

auditing . . . and would have no impact on . . . compliance with the standard.” 78 Fed. Reg. at 

29,952. However, EPA provides no explanation as to what this “volumetric auditing” is, if it 

applies to all gasoline/diesel (or, e.g., just RFG audits), or when it occurs. It simply is unclear 

why obligated parties need 90 days to identify their volumes and obligations under the RFS2 

program. That being said, NBB does not necessarily object to a March 31 deadline, so long as 

the extension is only intended to allow additional time to ensure accurate volumes are reported, 

and not to affect the RIN market. The Tier 3 Proposal provides no explanation as to whether the 

additional month will have an effect on the RIN market. Instead, EPA simply concludes that it 

will have no impact on compliance with the standard. There is substantial RIN activity in 

January and February to allow parties to true-up their RIN inventory to ensure they have 

sufficient RINs. As EPA is aware, there is much speculation in the RIN market, and it is unclear 

how this extension may affect that market. Moreover, many negotiations for fuel contracts for 

the coming year are done at the beginning of the year, when obligated parties apparently will still 

be addressing the prior year’s compliance. 

Further, NBB requests more information before EPA considers allowing ongoing RIN transfers 

in the EMTS through March 31 for compliance with the prior year. The RFS2 program is 

intended to spur production, and such an extension may only lead to more speculation and ease 

of purchasing prior year RINs rather than actual purchase of wet gallons. In either case, EPA 

does not provide sufficient explanation as to its proposed change, and, thus, NBB requests that 

EPA carefully consider such impacts and allow the public time to comment on its assessment.

In addition, in its comments on the Quality Assurance Program, NBB requested more 

transparency and consistency as far as reporting of available RINs and compliance by obligated 

parties. See EPA-HQ-OAR-2012-0621-0069 at 60-61 (Apr. 18, 2013). We are also concerned 

that the additional month will further delay EPA’s release of such information. Again, NBB 

requests that EPA carefully consider the potential impacts of the proposed change. 

NBB notes that EPA also has proposed to revise the due dates for the quarterly reports under 40 

C.F.R. § 80.1451(f). In particular, for the last quarter, EPA proposes to extend the deadline by an 

additional month. Again, NBB does not necessarily oppose the extension, but if the February 28 

deadline remains for obligated parties, their RIN activity and transaction reports should continue 

to be due the same date.
Tier 3 Summary and Analysis of Comments

6-31

Commenter: Shell Oil Products for Shell and Motiva

EPA requested comment on Amendments Related to RFS2 Annual Report Date,78 Fed. Reg. 

29952, specifically the date to be able transfer RINs in EMTS for satisfying RVOs for the 

previous compliance year. We request that the ability to transfer RINs in EMTS for satisfying 

RVOs under the previous compliance year be extended to March 31 to coincide with the 

proposed annual report date for other EPA programs. 

Commenter: Sutherland Asbill & Brennan LLP (Sutherland)

Reporting Deadlines. The Proposed Rule would change the reporting deadlines to enable the use 

of a unified and simplified reporting form and reduce the number of deadlines facing regulated 

parties. EPA solicited comments regarding whether the ability to transfer Renewable 

Identification Numbers (‘RINs’) in EMTS for the purpose of satisfying Renewable Volume 

Obligations (‘RVOs’) under the RFS from the previous compliance year should be extended to 

March 31. Sutherland believes this is a logical extension, and encourages EPA to extend the 

deadline to transfer such RINs to March 31.

Our Response:

EPA is finalizing the proposed changes to the RFS2 annual report date from the last day 

of February to March 31. EPA intended the change would 1) alleviate staffing problems for 

regulated entities because the regulatory requirements are often handled by the same personnel 

and 2) provide relief from the urgent need to obtain RINs when small discrepancies in gasoline 

production or import volumes are realized. Streamlining reporting dates will allow EPA to 

develop a single, user-friendly, electronic form that will collect all required data, maximizing the 

capability of electronic reporting to provide reuse of data and avoid duplicate data submission. 

Commenters generally agreed with the proposed date change. One commenter pointed out that 

the staffing issue described would not be addressed by the change date because EPA is changing 

both RFG and Anti-dumping compliance deadlines to March 31 – same as the RFS2 annual 

reporting. EPA understands the point made but nonetheless, believes that delaying the RFS 

reporting date will give reporting entities additional time and flexibility to review data and will 

have no impact on emissions, air quality, or compliance with the standard. EPA also believes that 

the overarching goal of streamlining reporting dates to develop a single electronic reporting 

format, in and of itself, will provide general relief to regulated parties. Comments received 

generally support this view. 

EPA requested comment on whether or not the same date extension from the last day of 

February to March 31 should apply to those transferring RINs in EMTS for satisfying RVOs 

under the previous compliance year. Some commenters wanted to have RIN trading through the 

new deadline (March 31), while others wanted trading to end on the last day of February to allow 

time for data cleanup which could improve compliance and reporting accuracy. One commenter 

also pointed out that changing the RIN trading deadline might have an unforeseen impact on the 

RIN market and suggested EPA carefully consider this possibility before making a decision on 

extending the RIN trading date. EPA agrees that providing enough time for data cleanup is 
Chapter 6: Regulatory Streamlining and Technical Amendments

6-32

important to ensure reporting accuracy and meet compliance goals. In addition, EPA understands 

stakeholders’ concerns about how such a change in RIN trading could conceivably impact the 

RIN trading market dynamics. As such, RIN transfers in EMTS for satisfying RVOs under the 

previous compliance year will continue to end on the last day of February.

6.1.2. Performance-Based Measurement Systems (PBMS)

6.1.2.1. Comments in Support of our Proposed PBMS Requirements

What Commenters Said:

All the comments we received were in support of PBMS.

Commenter: Chevron Products Company

Chevron supports to adoption of the Performance Based Measurement Standards concept. 

Chevron actively participated in the development of the API/AFPM comments on this proposal. 

We refer you to those comments as our detailed feedback on this section. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

We commend EPA for embracing a performance-based approach to specifying analytical testing 

requirements for fuel property measurements, as doing so allows for flexibility and encourages 

innovation. We broadly support the adoption of a PBMS for fuels, concur with EPA’s proposed 

categorization of fuel parameters as absolute- or method-defined, and urge the Agency to 

expedite its effort in extending PBMS to on-line analytics and automated sampling. 

We support the proposal of requiring Agency Approval for only non-VCSB methods. The dates 

and timing stated in the Preamble discussion section entitled “Agency Approval of Only NonVCSB Methods” and the dates contained in the proposed regulatory text on this topic, for the 

two sections are confusing and inconsistent. In addition, the exemption language in the two 

sections is not clear. Specifically, the Preamble states “We are also proposing to exempt existing 

(i.e., in use for six months prior to publication of this proposal) installations of designated test 

methods that are method-defined parameters from the qualification requirement.” We support the 

exemption clause as stated in the proposed regulatory language in §80.47 and suggest that the 

Preamble be written more clearly in order to properly reflect this text. 

Comment on whether the Agency should require qualification of all analytical test methods for 

the fuel parameters at 40 CFR 80. (78 Federal Register p. 29965) 

We do not support qualification requirement for all analytical test methods as suggested above. 

Commenter: Marathon Petroleum Company LP (MPC)
Tier 3 Summary and Analysis of Comments

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MPC supports adopting the Performance Based Measurement Systems proposal although we 

have provided some clarifications. We commend EPA for embracing a performance-based 

approach to specifying analytical testing requirements for fuel property measurements, as doing 

so allows for flexibility and encourages innovation.

Qualification criteria for designated test method installations that are “Method-Defined” 

parameters instruments and not used to qualify other “Method-Defined” methods (p. 29961): We 

agree with EPA’s proposal for only requiring implementation of a Statistical Quality Control 

(SQC) program as the sole qualification criterion for Designated Test Method installations that 

are not used to qualify alternate method-defined parameter instruments. 

Qualification criteria for method defined parameter instruments other than designated test 

methods (p. 29961): We agree with the proposed qualification criteria for Method Defined 

Parameter Instruments for VCSB Method-Defined Parameter Test Methods.

Statistical Quality Control for non-VCSB methods used to measure method-defined parameters: 

We support the proposal of requiring Agency Approval for only non-VCSB methods. 

Commenter: PBF Energy Inc.

PBF supports the inclusion of the proposed Performance Based Measurement Standard (PBMS) 

in the new rule for sulfur measurement.

Commenter: Shell Oil Products for Shell and Motiva

In general, we support the PBMS concept.

Commenter: Phillips 66 Company

Performance Based Measurement Systems – We are supportive of this effort – some 

modifications are suggested.

We are appreciative of the effort EPA has put forth to include a PBMS proposal in this 

rulemaking. The industry has been working collaboratively with EPA for many years to develop 

this concept – one that was first put into practice with the ultra-low sulfur diesel rulemaking. We 

support the proposal to exempt existing installations of designated test methods that have been in 

use for six months. As EPA states, requiring their qualification could be disruptive and 

burdensome to those operators and are already being used to certify fuels. 

Our Response:

We acknowledge the support. For those companies that participated in the issuance of 

the API/AFPM comments on PBMS compliance deadlines, applicability of PBMS to in-line 

blending and specific PBMS requirements, please see below for our response to these 

AFI/AFPM comments.
Chapter 6: Regulatory Streamlining and Technical Amendments

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6.1.2.2. Comments on the Proposed Compliance Period for PBMS

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

A one year grace period for ASTM D6708 Assessments on Voluntary Consensus-based 

Standards Body (VCSB) alternate method candidates for method-defined fuel parameters is 

inadequate. We suggest a minimum grace period of 18 months, given the time required to plan 

and complete such an endeavor. 

Commenter: Marathon Petroleum Company (MPC)

The dates and timing stated in the Preamble discussion section entitled “Agency Approval of 

Only Non-VCSB Methods” and the dates contained in the proposed regulatory text on this topic, 

for the two sections are confusing and inconsistent. In addition, the exemption language in the 

two sections is not clear. Specifically, the Preamble states “We are also proposing to exempt 

existing (i.e., in use for six months prior to publication of this proposal) installations of 

designated test methods that are method-defined parameters from the qualification requirement.” 

We support the exemption clause as stated in the proposed regulatory language in §80.47 and 

suggest that the Preamble be written more clearly in order to properly reflect this text. 

Commenter: Phillips 66 Company

The proposed timing of November 30, 2014 for labs to have completed their qualification of test 

methods is too aggressive. A lab could be currently using multiple alternative methods that will 

need to be qualified under these new provisions. We would anticipate some modifications to the 

proposed rule based on comments received. Labs would wait for final rulemaking and additional 

needed detailed guidance before beginning the qualification process. There is a need for further 

clarification and implementation guidance beyond what is in the proposed rule in order to 

develop uniform qualification processes. Also the qualification process for some methods 

requires reference instruments to meet certain criteria for at least five months prior to 

application. A minimum of 18 months from publication of the final rule is a much more 

reasonable time requirement for labs to complete the test qualification process. 

Commenter: Shell Oil Products for Shell and Motiva

We do believe, however, that in some ways the proposal is unnecessarily complicated and should 

be simplified. We agree with the proposal to exempt existing (in use for six months prior to 

publication of the proposal) installations of designated test methods that are method-defined 

parameters from the qualification requirement. We also agree with the proposed 40CFR 

80.47(b)(3) to exempt existing (in use for six months prior to publication of the proposal) 

installations of D2622 from the accuracy and precision qualification requirements.
Tier 3 Summary and Analysis of Comments

6-35

Our Response:

PBMS will be effective January 1, 2016, see Section VI.A.2.h of the Tier 3 final rule as 

well as 40 CFR 80.47. The Agency has chosen the approval option of only requiring Non-VCSB 

test methods to receive Agency approval starting January 1, 2016. VCSB test methods will be 

self qualified either through their respective VCSB or on a site specific basis. Please see Section 

VI.A.2.h of the Tier 3 final rule preamble as well as the final regulations at 40 CFR 80.47.

6.1.2.3. Applicability of PBMS to in-line Blending Methods

What Commenters Said:

We received several comments requesting our extension of PBMS to in-line blending 

methods.

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

EPA should expand PBMS to include sampling or in-line blending methods: Extension of the 

PBMS to sampling and in-line blending is a logical extension of this performance-based 

approach to the sampling and analysis of physical and chemical properties. We note that most if 

not all in-line analytical instrumentation is equal or superior to laboratory-based test methods in 

terms of precision as well as provision of a more representative analysis for the complete batch, 

as opposed to a laboratory analysis on an aliquot of a batch taken from a tank. Superiority in 

precision as well as overall representativeness of the batch is achieved by virtue of taking the 

average of many in-line analytical results during the manufacturing process. 

We note that there is a series of ASTM Standard Practices and Guides that prescribes industryconsensus best practices associated with the automated sampling and in-line analysis using 

process analyzers. See ASTM D7825 Standard Guide for Generating a Process Stream Property 

Value through the Application of a Process Stream Analyzer. We urge EPA to expedite its effort 

in extending PBMS to on-line analytics and automated sampling. 

Our Response:

The final requirements apply to the qualification of analytical test instrumentation and 

methods used to measure various characteristics of individual fuel samples. Consistent with our 

proposal, it does not apply to sampling methods or in-line blending methods. This is because, in-line 

blending already has a certification process that sets forth qualification criteria that take into account 

the unique combinations of sampling, control, and analysis that are involved with in-line blending. 

See 40 CFR 80.65(f).

6.1.2.4. Categorization of Fuel Parameters as Absolute or Method Defined

What Commenters Said:
Chapter 6: Regulatory Streamlining and Technical Amendments

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We received several comments in support of our categorization of fuel parameters as 

either absolute or method defined.

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

We commend EPA for embracing a performance-based approach to specifying analytical testing 

requirements for fuel property measurements, as doing so allows for flexibility and encourages 

innovation. We broadly support the adoption of a PBMS for fuels, concur with EPA’s proposed 

categorization of fuel parameters as absolute- or method-defined qualification criteria for method

defined parameter instruments other than designated test methods (78 Federal Register p. 29961).

We agree with the proposed qualification criteria for Method Defined Parameter Instruments for 

VCSB Method-Defined Parameter Test Methods. 

Commenter: Marathon Petroleum Company LP (MPC)

Categorization of fuel parameters as absolute or method defined: We support the proposed 

categorization of fuel parameters. We further support designation of Sulfur as the only Absolute 

parameter. 

Our Response:

The Agency is finalizing the categorization of fuel parameters as absolute or method 

defined as proposed. The absolute fuel parameters are sulfur in gasoline and sulfur in butane. 

All other fuel parameters besides sulfur have been finalized as method defined fuel parameters. 

The following fuel parameters are method defined fuel parameters: Olefins, Reid Vapor Pressure 

(RVP), Distillation, Benzene, Aromatic content of gasoline and diesel fuel, and Oxygen and 

oxygen content analysis.

6.1.2.5. Comments on the PBMS Requirements

EPA Should Not Extrapolate Precision Qualification Criteria for Absolute Parameters to 

Those Used for Method-Defined Parameters.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We commend EPA for embracing a performance-based approach to specifying analytical testing 

requirements for fuel property measurements, as doing so allows for flexibility and encourages 

innovation. While we broadly support the adoption of a PBMS for fuels as proposed by EPA, we 

do have a number of questions and concerns regarding the specific details as spelled out in the 

Notice of Proposed Rulemaking. Briefly, several of our main concerns include: 
Tier 3 Summary and Analysis of Comments

6-37

EPA should not extrapolate Precision Qualification Criteria for Absolute Parameters to those 

used for Method-Defined Parameters. We recommend that the precision standard deviation 

qualification criterion for method-defined parameters be based on a Test Performance Index 

(TPI) approach as per ASTM D 6792 Standard Practice for Quality System in Petroleum 

Products and Lubricants Testing Laboratories. We disagree with extrapolating the same 

precision qualification criteria for absolute parameters based on published method repeatability 

(r) to method-defined parameters. The basis for our disagreement is similar to EPA basis for 

recognizing the need for method-defined parameters. Specifically, the precision criteria of 

method-defined parameters are sensitive to the matrix of the material. This degree of sensitivity 

is different for different test methods / techniques / instrumentation that claim to measure the 

same property. We recommend that the precision standard deviation qualification criterion for 

method-defined parameters be based on a Test Performance Index (TPI) approach as per ASTM 

D 6792 Standard Practice for Quality System in Petroleum Products and Lubricants Testing 

Laboratories. Using the TPI as outlined in ASTM D6792 also is consistent with OMB Circular 

119 which directs agencies to use voluntary consensus standards in lieu of government-unique 

standards except where inconsistent with law or otherwise impractical. The TPI approach in 

ASTM D6792 sets minimum site precision performance criteria based on test method 

reproducibility (R) and the Precision Ratio (PR) of the published test method.

Our Response:

EPA has adopted the TPI approach for setting precision criterion for method defined 

parameters, see Section VI.A.2.c.iii of the preamble to the Tier 3 final rule as well as 40 CFR 

80.47.

EPA’s Proposed Accuracy Qualification Requirements for Reference Installations are Overly 

Restrictive 

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

EPA has proposed Accuracy Qualification Requirements for Reference Installations and for 

Designated Method Installations used to qualify method-defined parameter instruments which 

are overly restrictive. We are concerned that the proposed requirement to stay within the middle 

50% of the distribution of measurements of the industry monthly inter-laboratory crosscheck 

program for at least 5 months will severely restrict the number of participants. We suggest that a 

requirement of 3 out of 5 successive exchanges is more realistically achievable. The proposed 

qualification criteria for designated method installations used to qualify method-defined 

parameter instruments should be relaxed to be more realistically achievable.

Our Response:
Chapter 6: Regulatory Streamlining and Technical Amendments

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EPA has changed the requirement that reference installations of the designated test 

method should be shown to be in the middle 50% of the distribution measurements of an industry 

monthly inter-laboratory crosscheck program for 3 out of 5 successive exchanges. See Section 

VI.A.2.d of the preamble to the Tier 3 final rule as well as 40 CFR 80.47.

Sites Should Be Granted Greater Flexibility in the Choice of Procedures to Comply with the 

Proposed Statistical Quality Control (SQC) Requirements 

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

Sites should be granted greater flexibility in choosing procedures to comply with the proposed 

Statistical Quality Control (SQC) Requirements. We suggest that a site should be given the 

option of using either one of the two SQC procedures outlined in ASTM D6299, and not 

mandated to use both. 

Our Response:

The Agency agrees the Q-procedure is functionally equivalent to the I-procedure and that 

laboratories should be given the flexibility to use either of these two procedures instead of both, 

as proposed.

Recommend that EPA Specify ASTM D86-07

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

Table VI-6 (on p. 29958) lists EPA’s proposed precision criteria for Method-Defined Fuel 

Parameters with no Alternatives to the Designated Test Method. For the gasoline distillation fuel 

parameter, we recommend that EPA specify ASTM D86-07 for the following reasons: 

The precisions as published in later versions are not consistently supportable by actual ASTM 

ILCP program data; this is clearly stated in Note 31 of the current ASTM D86 test method: 

‘NOTE 31—A new inter laboratory study is being planned to address concerns that laboratories 

are not able to meet the precision for percent evaporated temperature at fifty percent.’

A plausible explanation is that the ILS study used to derive the current precision required several 

runs on the ILS material to select the heating profile, and hence does not reflect how the method 

is actually conducted in routine production environment. In addition, the ILS study sample set 

may not adequately cover the range of real world production gasoline available. 
Tier 3 Summary and Analysis of Comments

6-39

There is general consensus that the precision of this test method is sensitive to the slope of the 

boiling curve; hence, a constant precision as articulated in the cited ASTM D86-12 method may 

not be appropriate as a ‘one-size-fit-all’ measure for gasolines with different matrices and 

volatility properties (winter versus summer). Directionally, based on on-going discussions in 

ASTM, it appears that the ASTM test method precision may revert to a boiling curve slope based 

approach, similar to version ASTM D86-07. 

For gasoline containing 10% ethanol by volume (herein referred to as E-10), the boiling curve 

slope and hence precision is impacted by the location of the azeotrope point relative to the 

distillation points of interest (T10, T50, and T90). The azeotrope point is a function of the base 

stock (neat gasoline) composition, and therefore can vary with different matrices. We believe 

that precision function as stated in D86-07 is a more realistic representation for E-10 gasoline 

precision with different neat matrices. 

To support our concern that use of D86-12 precision and 1.5r is too restrictive, see the example 

of control chart data in Figure 15 [of EPA-HQ-OAR-2011-0135-4276-A2] supplied by a 

producer.

Our Response:

EPA has based the distillation precision criterion on ASTM D86-07, see preamble 

Section VI.A.2.c.iii and Table VI-9, as well as 40 CFR 80.47. In addition, the accuracy

demonstration must be based on the reference installation of the ASTM D86-07 test method 

along with use of ASTM D6708 in determining if a correction equation is warranted.

EPA’s Proposed Accuracy Qualification Requirements for Reference Installations Are Overly 

Restrictive

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

For a single entity that wishes to qualify alternate test methods per ASTM D6708 by using a 

single reference installation, we believe that the ‘middle 50 percent’ requirement as proposed by 

EPA is a reasonable requirement to impose on the single reference installation. However, we are 

concerned that the proposed requirement to stay within the middle 50% of the distribution of 

measurements of the industry monthly inter-laboratory crosscheck program for at least 5 months 

is overly restrictive. Based on a work up (provided as a separate attachment to these comments) 

of the proposed requirements (as we understand them) using ASTM D5599 Total Oxygen results 

on eleven RFG distributions, RFG1205 through RFG1303, we note that less than 15% of the 

participants met EPA requirement of staying within the central 50 percent for 5 successive 

exchanges. We specifically note that the EPA lab (lab 47) failed to meet this requirement. 

Therefore, we suggest a requirement of 3 out of 5 successive exchanges is more realistically 
Chapter 6: Regulatory Streamlining and Technical Amendments

6-40

achievable. We have attached the spreadsheet and description of the work up with these 

comments. See Attachments No. 4 and 5. 

The proposed qualification criteria for designated method installations used to qualify methoddefined parameter instruments should be relaxed to be more realistically achievable (78 Federal 

Register p. 29960).

We support in principle the qualification criteria described in the Preamble (at Section VI.3.e) for 

sites that intend to qualify other Method-Defined parameters using only a single designated 

method installation. However, as per our comment above in section IV.2 on Precision 

Qualification criteria, we believe that a more appropriate and realistically achievable standard 

deviation under site precision conditions for the method-defined parameter for both the 

designated method and alternate method installation, even by a ‘good’ lab, should be set based 

on the TPI approach in ASTM D 6792. 

We agree in principle with the additional accuracy requirement for a single Designated Method 

installation used to qualify alternate method-defined parameter instruments. However, as noted 

in an earlier comment above, we disagree with the requirement of staying in the middle 50 

percent for a minimum of 5 successive exchanges, and we suggest that 3 out of 5 successive 

exchange requirements is more realistically achievable. 

Our Response:

EPA has changed the requirement that reference installations of the designated test 

method should be shown to be in the middle 50% of the distribution measurements of an industry 

monthly inter-laboratory crosscheck program for 3 out of 5 successive exchanges. See section 

VI.A.2.d of the Tier 3 final rule as well as 40 CFR 80.47.

ILCP Data

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

For the situations where ILCP (such as those conducted by ASTM CS92) data and summary 

statistics for VCSB designated and alternate methods exist for the same materials, we believe 

that the summary statistics (mean and standard error = standard deviation / square root [ no. of 

results]) from these ILCP data can be used as is, i.e., without imposing the reference installation 

criteria, to conduct an ASTM D6708 assessment on VCSB alternate test methods, provided that 

the number of non-outlying results is >16 for both designated and alternate methods, since this is 

the current de facto methodology for determination of ARV of check standards as specified in 

ASTM D6299, clause 6.2.2.1 and Note 7. Therefore, per OMB Circular 119, we suggest that the 

ASTM D6299 protocol for establishing ARV be followed. We note also that in actual fact, 
Tier 3 Summary and Analysis of Comments

6-41

ASTM ILCP data for the method-defined parameters of interest exceeds this number (16) 

significantly.

We note that it is neither necessary nor is it statistically justified to apply the reference 

installation precision and ‘middle 50 percent’ criteria to the ILCP data for designated test method 

because the relevant ILCP statistics are calculated using outlier-free data, and, the number of 

data points is large, hence providing a better statistical ‘sample’ of the laboratory population. The 

mean calculated using the full ILCP, outlier-free data set is a ‘truer’ representation of the 

population parameter (μ) than the mean calculated using only the middle 50 percent. We note the 

standard error for the arithmetic mean calculated using the full ILCP data set is significantly 

reduced due to the square root [number of non-outlying results] term in the denominator for 

calculation of standard error. 

We urge that EPA clearly state that the use of ILCP data as described above is suitable for an 

ASTM D6708 assessment of VCSB alternate test methods. 

Our Response: 

The Agency has made the change in the final regulations to allow VCSBs to make use of 

ILCP data for conducting ASTM D6708 assessments for method defined fuel parameters.

EPA Should Provide an Example of an Acceptable ASTM D6708 Assessment

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We request that EPA provide a worked example of what the Agency deems to be an acceptable 

ASTM D6708 assessment. Doing so will provide valuable guidance to the regulated community 

with respect to understanding and implementing the provisions of the PBMS as outlined in the 

proposed rule.

Accuracy – the average of 10 consecutive results on a 1-10 ppm gravimetric sulfur standard 

cannot be more than 0.71 ppm and the average of 10 consecutive results on a 10-20 ppm 

gravimetric sulfur standard cannot more than 1.00 ppm.” 

To be consistent with the language in the NPRM, this statement should be revised as follows: 

“Accuracy – the average of 10 consecutive results on a 1-10 ppm gravimetric sulfur standard 

cannot be differ by more than 0.71 ppm from the ARV of the standard and the average of 10 

consecutive results on a 10-20 ppm gravimetric sulfur standard cannot differ by more than 1.00 

ppm from the ARV of the standard.” [Note: Strikeout = deleted text. Underline = added text.] 
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We appreciate the effort undertaken by EPA to develop flowchart examples of qualification 

requirements for Absolute Fuel Parameters and Method Defined Fuel Parameters and to place 

this material in the Docket for public comment. (See EPA-HQ-OAR-2011-0135-17841.) While 

these flowcharts are helpful, we urge EPA to develop more detailed schematics for inclusion in 

the final rule, as such information will be extremely helpful in assisting our members to 

implement the PBMS provisions. We also note that there is an error in the flowchart labeled 

“Flow Chart Example: Absolute Fuel Parameter (Absolute) – Sulfur in Gasoline” in Docket item 

EPA-HQ-OAR-2011-0135-17841.

Our Response: 

The flowchart examples have been corrected and placed in the docket to reflect the 

editorial comments for absolute fuel parameters and also to reflect specific comments the 

Agency has accepted in regards to method defined fuel parameters. For the absolute fuel 

parameter of sulfur, PMBS has been successfully demonstrated by over 800 test facilities for 

sulfur in diesel fuel. Therefore we believe the regulated industry is familiar with how to meet the 

accuracy and precision criterion for the absolute fuel parameters of sulfur in gasoline and sulfur 

in butane. For the method defined fuel parameter, such an example already exists in ASTM 

D6708 that is available to the industry and with which they are already familiar. If further

explanation is needed for either the absolute or method defined fuel parameter approaches, the 

Agency can do so through future discussions and guidance.

EPA Should Remove the Term ‘Robust’ from the Final Rule Preamble and Regulatory 

Language

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We note that the current ‘robust’ outlier treatment methodology for the ASTM CS92 ILCP 

program will be replaced with a statistically more rigorous approach using the Generalized 

Extreme Studentized Deviation (GESD) technique (37). We suggest that EPA remove the term 

‘robust’ from the Regulation (and Preamble) wording. 

Our Response:

EPA agrees with this comment and has thus removed the term “robust” from the 

applicable final regulations.

Sites Should be Granted Greater Flexibility in the Choice of Procedures for Statistical Quality 

Control (SQC) Requirements (78 FR 29962) 
Tier 3 Summary and Analysis of Comments

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What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We agree in principle with the SQC requirements, and that each instrument should be under its 

own SQC oversight. We note that in ASTM D6299, for the handling of QC material batch 

transition, the Q-procedure is intended to be an alternate approach to the concurrent testing 

(overlap) protocol. We suggest that the site should be given the option of using either one of the 

two procedures, and not mandated to use both. The Q-procedure is technically equivalent to the 

I-procedure. We suggest that for sites opting to use the Q-procedure, the very first run on the 

new QC batch should be validated by either an overlap in-control result of the old batch, or, by a 

single execution of an accompanying SRM. The new result is considered validated if the single 

result of the SRM is within the established site precision (R’) of the ARV. 

We suggest that because the standard error of the ARV in consensus-named fuels may not in all 

cases be negligible when compared to 0.75R, the expanded uncertainty of the ARV should be 

incorporated into the accuracy qualification criterion as follows: 

Accuracy qualification criterion = sqrt [(0.75R)^2 + (0.75R)^2/L], where L = the number of 

single results obtained from different labs used to calculate the consensus ARV. 

Our Response:

The Agency agrees the Q-procedure is functionally equivalent to the I-procedure and that 

laboratories should be given the flexibility to use either of these two procedures instead of both 

of these two procedures as proposed in the Statistical Quality Control requirements for PBMS. 

The Agency also agrees for sites opting to use the Q-procedure, the very first run on the new QC 

batch should be calibrated by either an overlap in-control result of the old batch, or by a single 

execution of an accompanying standard reference material (SRM). Thus the new result would be 

considered validated if the single result of the SRM is within the established site precision of the 

ARV of the SRM. We have revised the regulations to reflect these changes. See preamble 

Section VI.A.2.g as well as 40 CFR 80.47.

Qualification Criteria and Test Method Approval Date

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We support in principle the notion of requiring laboratories to meet prescribed qualification 

requirements for specifically cited measurement data quality assurance. We suggest that this can 

be further streamlined by selecting a subset of the regulated parameters for the purpose of 

demonstrating to the agency measurement capability, with the expectation that the quality 
Chapter 6: Regulatory Streamlining and Technical Amendments

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assurance work process and oversight for this subset of parameters are extended to all methods 

used to take measurement for regulatory purposes. 

The Preamble and the proposed Regulatory language are inconsistent with respect to the 

exemptions from the precision criteria for approval of the method defined fuel parameters 

granted for test methods in use prior to May 30, 2014. We support the exemption language stated 

in the proposed regulatory text at §80.47(b)(3), §80.47(c)(3), §80.47(d)(2), §80.47(e)(2), 

§80.47(f)(2), §80.47(g)(2). §80.47(h)(2), §80.47(h)(2), §80.47(i)(2), and §80.47(j)(2) and we 

suggest that the Preamble be revised in the final rule to more clearly reflect this wording. 

The proposed regulatory language exempting VCSB method-defined parameter test methods in 

use prior to May 30, 2013 (§80.47(l)(4)) is different than the May 30, 2014 date specified in all 

of the other precision criteria exemptions contained in the proposed regulatory text at §80.47 and 

noted above. Is this different date intentional?

Our Response:

The Agency is going forward with the exemption date for designated test methods as 

explained in the proposed preamble and has made this correction in the final regulations. The 

Agency has chosen the approval option of only requiring Non-VCSB test methods to receive 

Agency approval starting January 1, 2016. VCSB test methods will have the option to either self 

qualify either through their respective VCSB or on a site specific basis. Please see Section 

VI.A.2.h of the Tier 3 final rule preamble as well as the final regulations at 40 CFR 80.47.

Requirement for Test Method Qualification Applications to Include a Complete Operational 

Description of the Test Method in Question

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

If a VCSB method is used to measure and qualify either an absolute or a method-defined fuel 

parameter, we believe that a simple citing of the VCSB Test Method Number and Title should 

provide EPA with sufficient documentation with respect to its operational description We note 

that there is an inconsistency between the language of the preamble and that of the proposed 

regulation: the proposed regulation requires full documentation (see §80.47(l)(1)), while the 

preamble suggests otherwise. The final rule should specify that Test Method Qualification 

Applications need only to cite the VCSB by test method number and title. 

Our Response:

The Agency has chosen the approval option that only Non-VCSB test methods will be 

submitted for approval to that Agency. VCSB test methods will either qualify through their 

respective VCSB or on a site specific basis. The Agency agrees that during a potential audit, 
Tier 3 Summary and Analysis of Comments

6-45

reference to a particular VCSB test method designation number should suffice for the method 

utilized through self-qualification by that particular facility as long as the VCSB follows the 

requirements specified at 40 CFR 80.47(l). The Agency agrees that a simple citing of the ASTM 

test method designation number would suffice for requirements of the operational description of 

an ASTM test method. Please see 40 CFR 80.47.

Temporal Distribution of Precision Tests 

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We support option 2 (arranging tests into no fewer than five batches of five or fewer tests each, 

with only one such batch allowed per day) since it provides the most flexibility and is easier to 

implement.

Our Response:

The Agency has chosen option 2 (arranging tests into no fewer than five batches of five 

or fewer tests each, with only one such batch allowed per day) for temporal distribution of 

precision tests. Please see 40 CFR 80.47.

Statistical Control Requirements Governing the Operation of Reference Installations

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We support EPA’s proposal that the reference installation “...must be shown to be in statistical 

control, as provided for in ASTM D6299-10e1 ... and that the applicant must submit control 

charts showing a record of in-control operation for at least five months” but only with the 

proviso that:

Regular maintenance and/or re-calibration conducted during the 5 month in-control qualification 

period is considered as part of in-control normal operation, and 

If an assignable cause for ‘out of control’ is found, mitigated, and the system is brought back incontrol during the period that the reference installation is attempting to meet the 5 month instatistical-control requirement, the ‘clock’ for the 5 month period does not restart. In other 

words, the system is still considered as being ‘in control’. 

Our Response:
Chapter 6: Regulatory Streamlining and Technical Amendments

6-46

The Agency agrees and has made this change to the regulations. Please see applicable 

Statistical Quality Control requirements at 40 CFR 80.47.

Use of Reference Materials in Qualifying and Maintaining Alternative Analytical Techniques

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We support the philosophy and principle behind the use of the three types of Standard Reference 

Materials (SRMs) as discussed in the proposed rule. We suggest that for the Consensus-named 

fuels (SRM), EPA confirms that the relevant clauses described in ASTM D6299 (6.2) are 

acceptable in the determination of the Accepted Reference Value (ARV).

Use of reference materials in qualifying and maintaining alternative analytical techniques (p. 

29960): We support the philosophy and principle behind the use of the three types of Standard 

Reference Materials (SRMs) as discussed in the proposed rule. We suggest that for the 

Consensus-named fuels (SRM), EPA confirms that the relevant clauses described in ASTM 

D6299 (6.2) are acceptable in the determination of the Accepted Reference Value (ARV). 

Our Response:

The regulations state that a facility conduct tests on every instrument with a 

commercially available gravimetric reference material, or check standard as defined in the 

ASTM D6299 at least 3 times a year using good laboratory practices. 

5O) Qualification criteria for designated test method installations that are “Method-Defined” 

parameters instruments and not used to qualify other “Method-Defined” methods (78 Federal 

Register p. 29961)

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We agree with EPA’s proposal for only requiring implementation of a Statistical Quality Control 

(SQC) program as the sole qualification criterion for Designated Test Method installations that 

are not used to qualify alternate method-defined parameter instruments. 

Our Response:
Tier 3 Summary and Analysis of Comments

6-47

We acknowledge the support of this comment.

Test Performance Index

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

Test Performance Index (TPI) is defined in ASTM D6792 as follows: “an approximate measure 

of a laboratory’s testing capability, defined as the ratio of test method reproducibility to site 

precision.” 37 - Rosner, Technometrics, Vol. 25, May 1983

Our Response:

The Agency has incorporated by reference ASTM D6792 into the regulations.

Reference Installations

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Ashland Petroleum LP (MPC)

We support EPA’s proposal that the reference installation “...must be shown to be in statistical 

control, as provided for in ASTM D6299-10e1 ... and that the applicant must submit control 

charts showing a record of in-control operation for at least five months” but only with the 

proviso that: 

-Regular maintenance and/or re-calibration conducted during the 5 month in-control qualification 

period is considered as part of in-control normal operation

-If an assignable cause for ‘out of control’ is found, mitigated, and the system is brought back incontrol during the period that the reference installation is attempting to meet the 5 month instatistical-control requirement, the ‘clock’ for the 5 month period does not re-start. In other 

words, the system is still considered as being ‘in control’. 

Our Response: 

The Agency agrees and has made this change to the applicable accuracy and precision 

statistical control section of the regulations at 40 CFR 80.47(n)(2)(ii), 40 CFR 80.47(o)(2)(ii) and 

40 CFR 80.47(p)(2)(ii).

Repeatability Criterion Alternatives
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6-48

What Commenters Said: 

Commenter: PBF Energy Inc.

PBF will evaluate the option provided in the proposal to voluntarily convert other RFG test 

methods to PBMS. We are aware that some of the methods may have higher variability and it 

may be difficult to meet the precision qualification measurement requirements as proposed. EPA 

should examine alternatives to the 1.5 times repeatability criterion discussed in the proposal if it 

is desired to have more refiner participation in the voluntary portion of the program.

Our Response:

EPA has adopted the TPI approach for setting precision criterion for method defined 

parameters, see Section VI.A.2.c.iii of the preamble to the Tier 3 final rule as well as 40 CFR 

80.47.

6.1.2.6. Comments on the Proposed Regulatory Text

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

We also agree with the proposed qualification criteria for Method Defined Parameter Instruments 

for non-VCSB Method-Defined Parameters. However, we believe that in addition to having the 

degrees in Chemistry or Statistics, qualifications for third party oversight service providers 

should also have a good working knowledge of ASTM D6708 and ASTM D6299. In addition, 

believe that limiting the third party oversight qualification to only US degree holders will 

exclude non-US degreed subject matter experts with equivalent knowledge and qualification. We 

suggest that the wording be expanded to include non-US equivalent degreed or industry 

recognized subject matter experts. 

Commenter: Turner, Mason & Company

Under the proposed regulations, after November 29, 2014, the determination of sulfur in gasoline 

must be performance based, and other gasoline tests may be performance based. The 

performance based approval procedures are similar to those for the diesel sulfur determination. 

However, the EPA has added the additional step that the performance based procedures require 

an independent third party scientific review and written report, and verification of the 

information provided. The report and verification requires a site visit and review by an 

independent chemist and statistician who has received at least a bachelor’s degree in science 

from an accredited college in the United States, with professional work experience in the 

petroleum or oxygenate field.
Tier 3 Summary and Analysis of Comments

6-49

We propose that a chemical engineer with demonstrated experience in analytical techniques can 

perform the same function. Chemical Engineers have a strong background in chemistry, and, 

based on trends within industry, they will also have experience in statistical process control. 

Thus, we propose that the EPA should allow chemical engineers who can demonstrate their 

experience to be acceptable for providing an independent third party review and verification.

Our Response:

EPA agrees and has amended the final PBMS regulations to include chemical engineers

and non-US degreed subject matter experts with equivalent knowledge and qualifications as third 

party oversight reviewers. See Section VI.A.2.f of the Tier 3 final rule preamble and 40 CFR 

80.47.

What Commenters Said:

Commenter: Shell Oil Products for Shell and Motiva

We do believe, however, that in some ways the proposal is uncessarily complicated and should 

be simplified. The Agency requested comments on several items. For Agency Approval of Only 

Non-VCSB Methods, 78 Fed. Reg. 29964, we concur that only Non-VCSB methods need agency 

approval for method-defined parameters and absolute fuel parameters. Documentation should be 

submitted to the agency only for non-VCSB methods for qualifications for method-defined 

parameters and absolute fuel parameters. 

In regards to qualification of test methods, id., we believe the Agency should not require 

qualification of all analytical test methods for the fuel parameters in 40 CFR 80. 

In the proposed 40 CFR 80.47(k)(2), pertaining to criteria for reference installations, it mentions 

the use of an industry monthly inter-laboratory crosscheck program. In order to have the option 

to use other crosscheck programs besides ASTM, we recommend that the criteria for the 

reference installations refer to the use of a commercially available monthly inter-laboratory 

crosscheck program. 

Our Response:

The Agency is finalizing the exemption date for designated test methods as explained in 

the proposed preamble and has made this correction in the final regulations. The Agency has 

amended the regulations to allow commercially available inter-laboratory crosscheck program 

data for meeting PBMS qualificaiton requirements described in final regulations at 40 CFR 

80.47(k).

What Commenters Said:
Chapter 6: Regulatory Streamlining and Technical Amendments

6-50

Commenter: International Federation of Inspection Agencies (IFIA), Americas Petroleum 

Regional Technical Committee (APTRC)

It appears that EPA is proposing to add precision and accuracy requirements for tests that are put 

into use after May 30, 2014. These requirements are summarized in Table 1 [of EPA-HQ-OAR2011-0135-4292-A1].

There does appear to be any exclusions for Alternate Test Methods in Section 80.47 ((i)(4) and 

also in Sections ((b)(3), (d)(2), (f)(2), (g)(2), (h)(2), (i)(2). IFIA recommends that these sections 

be excluded from this requirement as well.

Section 80.47 (k)(2): IFIA interprets this section that reference installation of method defined 

fuel parameters (i.e., excluding Sulfur Test Methods) must be shown to be within an acceptable 

tolerance range of consensus value averages in Proficiency Testing Programs. They also must be 

monitored by SQC in accordance with D6299. 

Based upon this interpretation is appears that correlations of Alternate Test Methods to Primary 

Test Methods may only be performed using a Reference Installation. IFIA recommends that 

there be a provision for correlating to Primary Test Method ARV’s of ILCP samples as well. 

Section 80.47 (l)(1-4): This section states that for test methods that are not listed as being a 

Primary Test Method (including Alternate Test Methods, VCSB Test Methods that are not listed 

as being an Alternate Test Method and Non-VCSB Test Methods), their precision should be 

evaluated according to sections (b) through (i) and accuracy should be evaluated according to 

D6708. Also, regarding the accuracy check, if the difference is “null” then a correlation need not 

be applied but if “not null” then a correlation needs to be applied to the Primary Test Method. 

Based on the above section, it seems evaluation by D6708 is mandatory. However IFIA 

recommends that it should be up to the laboratory to do a correlation in lieu of this, even if by 

D6708 it would not be required. The reasoning for this is that as time elapses a lab may find 

itself in and out of meeting D6708 tolerance requirements. 

Sections 80.47 (1) and (2): IFIA requests confirmation of the following interpretations: 

For Sulfur determinations, Gravimetric Reference Standards or Check Standards will need to be 

analyzed at least quarterly and once 15 or more results are gathered both an I and MR Chart 

should be constructed with control limits as defined in this section of the CFR. 

That SQC be in place according to D6299 and that the Q procedure be used when replacing QC 

Material. 

Sections 80.47 (o)(1) and (o)(2): This section is applicable to the Non-Sulfur Test Methods and 

basically the same as 80.47(n)(1), the accuracy check standard must be on an “ordinary fuel”.

IFIA has two recommendations on this element of the section. Regarding the proposal that the 

accuracy check standard be an “ordinary fuel”, this may cause issues over time as the integrity of 

a gasoline sample will likely be compromised. This is of particular concern for RVP and Olefins 

where there will be a propensity for drift and also Distillation where there will be a sizeable 
Tier 3 Summary and Analysis of Comments

6-51

sample consumption. First, IFIA recommends that labs be allowed to plot the delta from the 

ARV [Accepted Reference Value] (obtained value minus ARV) instead of the obtained value. 

Second, instead of being mandated that this be done quarterly, IFIA would recommend three (3) 

times per year so that this requirement is in-line with ASTM ILCP sample cycle frequency. 

This section states that the ARV must be determined according to D6299. IFIA believes this is 

an odd statement as the ARV is usually representative of the consensus value or mean (after 

outliers have been rejected). 

This section also includes a mandate for monitoring the average of the most recent result and the 

one preceding it to determine if that average is greater than 0.75R. IFIA views this as overly 

complex. IFIA proposes that each value be compared against R instead. 

Below 80.46 (h)(1)(vii), it seems as though the next section should list the test method for RVP 

(D5191-10b EPA Eq). 

IFIA recommends adding a Section 80.47 (a)(14) to further explain the term reference 

installation as referred to in 80.47 (k). This is defined (at least somewhat) in the EPA Tier III on 

page 29958, column 1 midway down, as a method used for qualifying an alternate test method.

Our Response:

Effective January 1, 2016, for the reasons discussed in the Tier 3 proposed and final rule, 

all alternative test methods must meet the PBMS criterion described at 40 CFR 80.47. The 

Agency has amended the regulations to allow the use of both commercially available and 

voluntary consensus standards board inter-laboratory cross check data in meeting the PBMS 

criterion described at 40 CFR 80.47. If a laboratory chooses to use either a VCSB or non-VCSB 

method defined fuel parameter test method, in meeting the PBMS criterion for accuracy, the lab 

must use ASTM D6708 to determine the need for a correction equation. Please see our final 

regulations at 40 CFR 80.47. The Agency has made rule language changes to reflect that test 

facilities can conduct verification of new QC material three times a year in order to align this 

requirement with ASTM ILCP program sample cycle frequency.

What Commenters Said:

Commenter: Weaver and Tidwell LLP

i. As currently proposed, the primary regulatory methods and alternative regulatory methods 

listed in 80.46 are exempted from the performance based testing requirements in 80.47. Is the 

exemption for the methods listed in 80.46 dependent on 80.46 complying exactly with all the 

requirements listed in those methods (i.e., apparatus, reagents, calibration, quality control, 

procedures, calculations, etc.)? If the requirements of these methods are not followed exactly or 

are modified in any manner, do the modifications constitute a new method that must be qualified 

as required in 80.47? 
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ii. Change the wording in 80.46(a)(1) – The wording in this section uses the word “must” 

concerning the use of 80.47 after the appropriate date in 2014. Other paragraphs in this section 

use the word “may”. We request that EPA change the word in 80.46(a)(1) from “must” to “may” 

for consistency. 

Some specific modifications to the 80.46 method are listed below. Would any of the listed 

modifications to the method individually or in combination be sufficient to void the exemption 

from the performance based requirements of 80.47? As a secondary associated question, would 

the EPA cite any of these modifications in enforcement actions? 

(a) For olefin content (80.46(b)), ASTM D1319, Section 6.5 requires the use of a hypodermic 

syringe with a needle having a length of 102 mm. Would the use of a hypodermic syringe with a 

needle having a length of ~ 50mm be sufficient to void the exemption from the requirements of 

80.47? 

(b) For olefin content (80.46(b)), ASTM D1319, Section 7.2 requires that the fluorescent 

indicator dyed gel be stored in a dark place under an atmosphere of nitrogen. Would the failure 

to store the fluorescent indicator dyed gel in a dark place under an atmosphere of nitrogen be 

sufficient to void the exemption from the requirements of 80.47? 

(c) For olefin content (80.46(b)), ASTM D1319, Section 10.1 requires that the appropriate 

amount of fluorescent indicator dyed gel (3 – 5 mm) be added to the analytical column. Would 

the addition of an inappropriate amount of fluorescent indictor dyed gel (less than 3 mm or more 

than 5mm) be sufficient to void the exemption from the requirements of 80.47? 

(d) For olefin content (80.46(b)), ASTM D1319, Section 10.3 requires that the hypodermic 

syringe be chilled to less than 4 °C. Would failure to chill the hypodermic syringe to less than 4 

°C be sufficient to void the exemption from the requirements of 80.47? 

(e) For olefin content (80.46(b)), ASTM D1319, Section 10.5 requires that the second set of 

readings of the zone measurement boundaries be made after the sample has advanced at least 

another 50 mm down the column. Would making the second set of readings before the sample 

had advanced another 50 mm down the column be sufficient to void the exemption from the 

requirements of 80.47? 

(f) For olefin content (80.46(b)), ASTM D1319, Section 11.1 requires that percentages of 

hydrocarbon types be calculated for each set of readings and then that the percentages of 

hydrocarbon types from each set of readings be averaged to obtain the reported values. Would 

calculating the reported values in a different way (averaging the zone lengths from each of set of 

readings and then calculating the percentages of hydrocarbon types using the averaged zone 

lengths) be sufficient to void the exemption from the requirements of 80.47? 

(g) For Reid vapor pressure (80.46(c)), ASTM D5191, Section 8.4.1 requires that, for transparent 

containers, the sample container be opened to momentarily, even if the appropriate liquid level 

can be verified externally. Would failure to open the transparent container prior to beginning the 
Tier 3 Summary and Analysis of Comments

6-53

aeration cycles required in Section 8.4.2 volume can be verify the be sufficient to void the 

exemption from the requirements of 80.47? 

(h) For Reid vapor pressure (80.46(c)), ASTM D5191, Section 11.1 requires a verification 

standard be tested every day the analyzer is used to perform testing. Recommended verification 

standards are listed in Section 7 and those suggested verification standards having calculated 

acceptable testing range intervals listed in Table 1. Section 11.2 requires that, if the verification 

standard results are outside the acceptable testing range intervals listed in Table 1, the 

verification standard must be rechecked or the calibration of the analyzer must be checked. 

Would the use of a verification standard not listed in Section 7 or Table 1 that does not have an 

established acceptable testing range interval (i.e. hexane) be sufficient to void the exemption 

from the requirements of 80.47? 

(i) For distillation (80.46(d)), ASTM D86, Section 10.19 requires that the residue be measured in 

a 5 mL graduated cylinder. Would measurement of the residue using a graduated cylinder having 

a different volume (i.e. 10 mL marked with 0.1 mL graduations) be sufficient to void the 

exemption from the requirements of 80.47? 

(j) For aromatic content (80.46(f)), ASTM D5769, Section 11.1 requires that ~ 10 grams of 

sample be mixed with the appropriate volume of internal standard during the sample preparation 

procedure. Would the use of a significantly different amount of sample (i.e. ~ 1 gram) during the 

sample preparation procedure be sufficient to void the exemption from the requirements of 

80.47? 

(k) For oxygenates (80.46(g)(2), ASTM D4815, Section 13.1 requires that the sample and 

internal standard be prepared in a capped 10 mL volumetric flask. Given the sample is being 

prepared gravimetrically, would preparation of the sample in a different type of container (i.e. a 

capped 10 mL scintillation vial) be sufficient to void the exemption from the requirements of 

80.47? 

iii. Questions relating to 80.46 - Can the procedures in ASTM D6708 be used to avoid the 

requirement to correlate the results from the alternate methods listed in 80.46 to the primary 

regulatory methods listed in that section? In our reading of 80.46, sections 80.46(a)(3) for sulfur 

content, 80.46(b)(2)(ii) for olefin content, 80.46(f)(3)(ii) for aromatic content, and 80.46(g)(2)(ii) 

for oxygen content refiners and importers must report results from the alternate methods that 

have individually been correlated to the primary regulatory methods. Our interpretation appears 

to be supported by the attached excerpt from the EPA Q&A documents (see Appendix 1). 

Demonstrating acceptable correlation between the alternate methods and the primary methods 

using the procedures in ASTM D6708 would not ensure that an analytical result from an 

alternate method that was determined by an individual measurement system would be 

mathematically identical to the result determined by the primary reference method (consistent 

with the specified reporting significant figures). If the EPA contemplates allowing the use of the 

procedures in ASTM D6708 to eliminate the requirement to correlate the alternate methods to 

the primary regulatory methods in 80.46, then the text in sections 80.46(a)(3), 80.46(b)(2)(ii), 

80.46(f)(3)(ii), and 80.46(g)(2)(ii) will have to be revised. 
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iv. 80.47(l)(3) – This section requires that a VCSB Method-Defined Parameter test method that 

is a candidate for qualification provide information about whether or not a correlation equation 

must be applied that predicts the designated test method results from the applicable methoddefined alternative test method. 

In our experience, it is likely that some laboratories may wish to qualify ASTM D6378 as a 

method-defined alternative test method for measuring Reid vapor pressure. ASTM D6378 

includes a correlation equation to convert test results from ASTM D6378 to an equivalent value 

determined by ASTM D5191. However, that correlation equation relates the result from ASTM 

D6378 to a Reid vapor pressure determined by ASTM D5191 using the correlation equation in 

ASTM D5191, Section 14.2 (DVPE, psi = (0.965*X) - 0.548) rather than the equation required 

in 80.46(c) (RVP, psi = (0.956*X) – 0.347) where X = the total vapor pressure. For results 

generated according to ASTM D6378, the correlation equation specified in the method is 

insufficient to produce a Reid vapor pressure result equivalent to the original method and must 

be modified further to yield a result equivalent to the results required by 80.46(c). 

v. Remove wording from 80.47 - EPA should consider removing the requirement that “All 

sample handling, testing, procedures and tests must be conducted using good laboratory 

practices” from 80.47. We agree that use of good laboratory practices is an excellent idea, 

however, the definition of “good laboratory practices” is somewhat subjective and the 

regulations provide no referenced list of “good laboratory practices” - providing a legally 

enforceable set of criteria. 

Our Response: 

i) Only those designated test method in use 6 months prior to the publication of the Tier 3 

final rule are exempt from the PBMS accuracy and preicsion criterion described at 40 CFR 

80.47. Those designated test methods will still be required to meet the applicable SQC 

requirements described at 40 CFR 80.47. In addition, if the user of a particular VCSB test 

method decides to deviate from the required apparatus, reagents, calibration, quality control, 

procedures or calculations, etc., that are specified in a particular VCSB test method, then by 

definition, the user would not be meeting the operational description of the VCSB test 

method, and thus have the option to qualify such a test method as a non-VCSB test method.

ii) Once PBMS is effective, January 1, 2016, all test methods must meet the requirements 

of 40 CFR 80.47, except those designated test methods in use 6 months prior to the publication 

of the Tier 3 final rulemaking. In regards to questions 6(D)(ii)(a) through 6(D)(ii)(k), as stated 

above, if a user of a particular VCSB test method decides to deviate from the required apparatus, 

reagents, calibration, quality control, procedures or calculations, etc., that are specified in a 

particular VCSB test method, then by definition, the user would not be meeting the operational 

description of the VCSB test method, but that user does have the option to qualify such a test 

method as a non-VCSB test method. The Agency notes one exception, for question B(f) on 

olefin content, where Weaver and Tidwell LLP asks about a particular modification to D1319, 

Section 11.1 requires that percentages of hydrocarbons types from each set of readings be 

averaged to obtain reporting values. Would calculating the reported values in a different way 

(averaging the zone lenghts from each set of readings and then calculating the percentages of 
Tier 3 Summary and Analysis of Comments

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hydrocarbon types using the averaged zone lenghts) be sufficient to void the exemption from the 

requirements of 90.47? The answer is no, unless the mathematics, including the oxygenate 

correction, yields different results.

iii) Once PBMS is effective, on January 1, 2016. the user of a VCSB method defined test 

method or Non-VCSB test method must utilize ASTM D6708 to determine the need for a 

correction equation for the candidate alternative test method. Please see the final regulations at 

40 CFR 80.47.

iv) For RVP, once the user of an alternative test method such as ASTM D6378 has 

demonstrated thourgh the use of ASTM D6708 whether a correction equation is needed or not, 

they will still need to use the equation described in 40 CFR 80.46(c) for reporting purposes for 

the RVP fuel parameter.

v) EPA believes that all sample handing, testing, procedures and tests must be conducted 

using good laboratory practices and thus has retained the term good laboratory practices in the 

regulations.

6.1.3. Downstream Pentane Blending

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

EPA has asked for comment regarding allowing downstream pentane blending into gasoline 

using a similar construct as currently exists for butane blending. The Agency has not proposed 

any specific regulatory language but rather is looking for input on the concept of downstream 

pentane blending. Pentanes exist in the gasoline mixtures being sold today as gasoline 

encompasses a broad range of hydrocarbons that result from the refining and gasoline blending 

processes. Theoretically, it would be possible to establish pentane specifications and processes 

akin to the existing butane blending provisions. EPA poses additional questions regarding 

whether further downstream blending of pentane into PCG would have any vehicle emissions 

and operability effects. API does not have any specific data to respond to this specific question. 

However, it would seem that if the volumes of pentane expected to be blended result in 

concentration levels that are already found in existing gasoline blends that would provide some 

assurance. We would encourage EPA to look at the range of C5s contained in the gasolines being 

marketed today and then examine some pentane blending scenarios to determine possible C5 

content of the blended gasoline. There should be a theoretical limit on the volume of C5 that 

could be blended based on vapor pressure and volatility limitations. 

Commenter: Independent Fuel Terminal Operators Association (IFTOA)
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EPA also explains in the Preamble that there is a substantial increase in the production of natural 

gasoline liquids (such as pentane) occurring as a by-product from the increased production of 

domestic natural gas and crude oil in the United States. In addition, butane blenders have asked 

EPA to broaden the downstream butane blending provisions to include pentane to help increase 

the domestic supply of gasoline and to take advantage of this enhanced natural gasoline liquids 

market. Finally, EPA states that pentane blending may have a marginally beneficial effect on 

vehicle emissions. For these reasons, the Association supports expanding the downstream 

butane blending provisions to include pentane. 

Recommendation: The Association recommends that EPA continue to provide flexibility to 

butane blending and consider a requirement that butane only need meet the downstream pergallon sulfur cap so long as the butane blending operation does not cause the annual average 

sulfur content of the gasoline to exceed the proposed Tier 3 standard of 10 ppm. Moreover, the 

Association supports broadening the butane blending provisions to include pentane. Provide 

greater flexibility for butane blending and expand butane blending provisions to include pentane.

Commenter: Magellan Midstream Partners, L.P.

EPA currently provides flexibility for butane a blender which reduces the compliance burden. 

Should EPA provide the same flexibility for pentane blenders? 

Magellan Comment — Yes, absolutely. We agree that it would be appropriate to allow pentane 

meeting certain specifications (specifications which include RVP and volatility limits) to be used 

in the production of gasoline using a method which would reduce the compliance burdens 

normally associated with refiner sampling and reporting. However, we do not believe this should 

be limited to ‘pentane’ but should as also include gasoline range hydrocarbons. For instance, 

heavy naphtha can be an appropriate gasoline blendstock, but would not fit in the pentane or 

natural gasoline definition. 

Also as discussed, we encourage EPA to include a provision in the final rule which will provide 

compliance requirements for refiners that blend pentane or other gasoline range hydrocarbons 

downstream similar to those that apply to butane blenders. We feel it is appropriate to extend this 

opportunity to all gasoline range hydrocarbons rather than just for pentane blending. As greater 

levels of domestic oil and gas are produced, our nation will have increased natural gas liquids 

(NGLs) available for domestic utilization. We believe it is appropriate to allow gasoline range 

hydrocarbons meeting certain specifications to be used in the production of gasoline using a 

method which would reduce the compliance burdens normally associated with refiner sampling 

and reporting.

Commenter: Sunoco Logistics Partners L.P.

Sunoco Logistics also supports the broadening the downstream butane blending provisions to 

include pentane, provided the finished gasoline meets all applicable federal and state motor fuel 

quality standards. There has been rapid and unprecedented growth in the production of natural 

gas liquids (ethane, propane, butane and natural gasoline) - by products of the increased domestic 
Tier 3 Summary and Analysis of Comments

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natural gas and crude oil development in multiple shale regions in the U.S. We see a substantial 

opportunity to increase domestic gasoline supply with the downstream blending of the pentane 

fraction of natural gasoline streams. Pentanes (C5) are clean burning alkanes like butane (C4). 

Like butane the pentane fraction has always been present in gasoline. With a significantly higher 

boiling pointPentanes 82-97 °F

Butanes 11-31 °F

downstream blending of pentane at a constant volatility will result in reduced vehicle evaporative 

emissions than downstream butane blending. 

Pentane blending and the specifications required to assure proper finished fuel performance and 

vehicle operability should generally mirror existing butane specifications:

Commercial Grade Pentane95% purity minimum

Sulfur <= 30ppm, then <=10ppm consistent with Tier 3 implementation date

Benzene <= 0.03 volume percent

Olefins <= 1.0 volume percent

Aromatics <= 2.0 volume percent

C6+ content <= 5.0 volume percent

Non- Commercial Grade PentaneSulfur <= 30ppm, then <=10ppm consistent with Tier 3 implementation date

Benzene <= 0.03 volume percent

Olefins <= 10.0 volume percent

Aromatics <= 2.0 volume percent

C6+ content <= 5.0 volume percent

Downstream testing and oversight provisions for the commercial and non-commercial pentane 

streams could similarly parallel existing regulations for butane blending. 

With these specifications assuring fuel performance, vehicle operability and the aforementioned 

reasons of increased domestic gasoline supply and lower evaporative emissions, the effective 

date of new pentane blending regulations should be set upon Final Rule publication. 

Downstream Butane and Pentane Blending Sulfur Credit or Averaging Provisions: The proposed 

reduction in gasoline sulfur levels requires significant lead time and flexible compliance options 

to ensure a stable, adequate and affordable supply of fuel for the consuming public. Historically, 

EPA has devised various credit and averaging options for some transition period to ease supply 

concerns due to non-compliance. Like refiners, downstream blenders face the same challenges 

with the Tier 3 sulfur rules. A major supply source of the downstream blend components are the 

impacted domestic refiners and importers. Supply of 10ppm butane and pentane five years into 

the future is difficult to forecast. During the most recent transition from 140 to 30ppm in butane 

blending gasoline in 2003-5, a significant portion of the butane supply for blenders was noncompliant. Projecting forward to the implementation of the new Tier 3 Sulfur rules, it is realistic 

to expect a similar and perhaps more significant portion of supply from refiners and importers 

would be similarly noncompliant with the proposed 10ppm level. Accordingly, annual averaging 

for butane and pentane blenders to the 10ppm with the present 30ppm cap seems reasonable, 
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uncomplicated and sufficient to maintain adequate, stable supply during the transition. At a 

minimum, blenders should have the same type of compliance flexibility as refiners during the 

transition period.

Our Response:

As discussed in Sections V.I and VI.A.3.of the preamble to the final rule, and consistent 

with our proposal, we are finalizing pentane blending provisions that are similar to those in place 

for butane under the Tier 2 program.3 We are finalizing a 30 ppm sulfur cap for pentane blended 

into PCG (blender-grade) that will be effective until December 31, 2016, after which a 10 ppm 

sulfur cap will become effective. This is consistent with the Tier 3 10 ppm refinery average 

gasoline sulfur specification and Tier 3 specifications for butane blended into PCG.

As is the case with butane used by downstream butane blenders, we believe that blendergrade pentane that can be manufactured to meet the Tier 3 program sulfur caps with relatively 

mild desulfurization techniques and/or the choice of low-sulfur feedstocks. We further believe 

that allowing pentane used for RVP trimming to exceed a 10 ppm sulfur cap would needlessly 

complicate compliance assurance, defer some of benefits of the Tier 3 sulfur requirements, and 

would be inconsistent with the premise of implementing additional programmatic flexibilities 

that do not detract from the environmental goals of the Tier 3 program.

During our discussions with stakeholders following the proposal and from the review of 

public comments, we became aware of additional potential issues associated with assuring the 

quality of pentane for gasoline blending beyond those that exist for butane. In response to 

comments and to further limit variability in pentane quality, C6 and higher hydrocarbons in 

pentane blended into gasoline must be limited to 5 volume percent or less. In phone 

conversations with stakeholders during our review of the written comments, we were also made 

aware of the possibility that parties that handle natural gasoline liquids (NGL) might misinterpret 

the pentane blending provisions finalized today to apply to natural gas liquids. 4 A pentane 

stream for gasoline blending does not currently exist, and there are currently varying definitions 

of NGL, which is sometimes referred to pentanes-plus. Concerns also arose regarding potential 

contamination if the same equipment is used to transport blender grade and NGL. Consequently, 

in today’s rule, we are finalizing the following additional requirements, that will preclude 

potential confusion of NGL with blender grade pentane, help ensure that the quality of blender 

grade pentane is maintained throughout the distribution system, and facilitate EPA enforcement 

and compliance assurance of the quality requirements for blender grade pentane.5

We believe that the butane blending provisions have reduced the burden of compliance 

with EPA gasoline quality requirements. We anticipate that expanding the provisions to allow 

pentane to be blended into PCG that we are finalizing in the Tier 3 FRM will further reduce the 

burden of compliance. The requirement that final blends must comply with maximum gasoline 

volatility requirements will ensure that the flexibility to conduct downstream RVP trimming will 

 

3 The requirements for butane blenders are found in 40 CFR 80.82.

4 Memorandum to the docket entitled “Tier 3 Phone and E-Mail Log”.

5 The requirements for producers of blender-grade pentane and for pentane blenders are discussed in Section VI.A.3. 

of the Tier 3 FRM preamble. 
Tier 3 Summary and Analysis of Comments

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not reduce the environmental benefits of EPA’s gasoline quality requirements. Due to its lower 

volatility compared to butane, larger volumes of pentane than butane can be blended into 

gasoline while still meeting the gasoline RVP standards. Thus, allowing pentane to be blended 

into gasoline downstream of the refinery may displace butane blending. Since pentanes have a 

lower boiling point than butane, this could result in some environmental benefit from reduced 

vehicle evaporative emissions. 

We are not expanding the downstream blending provisions beyond pentane in today’s 

rulemaking. Pentane is a clean burning alkane like butane. The only concern with respect to the 

effect of downstream pentane and butane blending on vehicle emissions can be addressed 

through compliance with gasoline maximum volatility requirements. Less is known about the 

potential impacts on vehicle emissions of the downstream blending of blendstocks other than 

butane and pentane. We note that such blendstocks can still be utilized by refiners. 

We therefore disagree with the comment that we should allow blending of heavier boiling 

range hydrocarbons, such as heavy naptha, would also likely raise additional compliance 

assurance issues. Similar to butane, blender grade pentane requires special pressure vessels for 

transport, storage, and blending into gasoline due to its relatively high vapor pressure / boiling 

point.6 These special equipment and handling needs present significant barriers to entry into the 

pentane blending market, thereby limiting the potential number of parties engaged in the market. 

The substantial investments needed for such special equipment also provides assurance that 

parties engaged in the pentane blending market will be motivated to comply with EPA 

requirements. These factors make us confident that the compliance assurance requirements 

finalized in the Tier 3 FRM are sufficient to support provisions for pentane blending. On the 

other hand, in the case of heavier hydrocarbons that are liquid under ambient conditions, gasoline 

handling equipment could be used. This would greatly multiply the number of potential parties 

that could supply product to downstream blenders, thereby substantially increasing compliance 

assurance concerns. Therefore, we are not finalizing provisions for downstream blending of 

hydrocarbons other than blender-grade pentane.

6.1.4. Top Tier Detergent Equivalence

What Commenters Said

Commenter: Chevron Products Company

Regulatory Streamlining General Requirements and Deadlines – Gasoline Deposit Control 

Program 

Chevron’s experience with respect to compliance with EPA’s and the top tier deposit control 

requirements confirms the following statement in this section: ‘It is widely accepted that 

conformance with the Top Tier intake valve deposit (IVD) and fuel injector deposit (FID) control 

testing is more challenging than complying with the EPA IVD and FID testing requirements.’ In 

 

6 The boiling point of pentane is ~ 97° F and butane is ~30° F.
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fact, our years of extensive experience with respect to deposit control and related vehicle/engine 

performance testing, combined with the vast body of technical literature on the subject, shows 

that compliance with the Top Tier IVD/FID requirements results in enhanced improvements in 

emissions and performance compared to fuels with deposit control additive levels that merely 

meet EPA’s deposit control requirements. 

Chevron supports EPA’s proposal to accept test data demonstrating conformance with the Top 

Tier program as alternative data under EPA’s Deposit Control Program. 

However, in proposed regulation §80.177(b)(1)(iv), EPA proposes that test fuel used for intake 

valve deposit testing using the procedure specified in §80.176(b) (the Top Tier IVD test) contain 

‘no less than 240 ppm sulfur.’ The Top Tier Deposit Control Standard section 1.3.1.2 clearly

states that the fuel shall ‘Contain no less than 24 mg/kg sulfur.’ Given EPA’s consideration of 

permitting Top Tier IVD/FID data as an alternative, we believe the proposed 240 ppm minimum 

sulfur requirement in this proposed section is the result of a typographical error and should be 

corrected to 24 ppm (mg/kg) in the final rule.

Our Response:

As discussed in Section VI.A.4. of the preamble to the final rule, we are adopting the 

proposed amendments to EPA’s gasoline deposit control regulations to accept test data collected 

for the industry-based “Top-Tier” deposit control program as demonstration of compliance with 

EPA’s intake valve deposit (IVD) and fuel injector deposit (FID) control requirements. We note 

that we received comments that supported the “Top Tier” deposit control gasoline standards 

developed by four major automakers because they provide a more robust level of the control of 

vehicle engine and fuel systems than that provided by the EPA deposit control requirements.7 

We also note that several major gasoline marketers have adopted Top Tier for their gasoline. 

Accepting IVD/FID test data that complies with the Top Tier requirements in place of the 

standard EPA IVD/FID testing requirements will provide significant savings to industry from 

reduced deposit control testing while maintaining the emissions benefits of EPA’s gasoline 

deposit control program. 

In response to the comments that identified a typographical error in the proposed 

regulations to codify the Top Tier testing requirements at §80.177(b)(1)(iv), i.e., test fuel used in 

IVD testing must contain no less than 240 ppm sulfur, we have corrected the error in the 

regulations finalized in the Tier 3 final rule. The revised §80.177(b)(1)(iv), now states that test 

fuel used in IVD testing must contain no less than 24 ppm sulfur, consistent with the Top Tier 

deposit control standard.

6.2. Engine, Vehicle, and Equipment Program Technical Amendments

6.2.1. Engine and Vehicle Test Procedures (including Reference Methods)

 

7 The industry-based Top Tier deposit control program is discussed at http://www.toptiergas.com/
Tier 3 Summary and Analysis of Comments

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6.2.1.1. Heavy-Duty Vehicle Testing

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

HDV Testing: Discusses HDV evap test procedures. To simplify and streamline the CFR 

regulations industry proposes that EPA reference the LD evap test procedures and remove the 

HD evap test procedures from the HD subpart. LD evap test procedures would be utilized for all 

chassis certified evaporative emission testing.

Our Response:

We agree with the comment and have drafted the final rule accordingly.

6.2.1.2. Durability

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Component Durability: We note that proposed §§ 86.1823-08(g) and 86.1824-08(h) direct 

manufacturers to “use good engineering judgment to determine that all emission-related 

components are designed to operate properly for the full useful life of the vehicles in actual use.” 

The Alliance and Global Automakers support this language. 

Automobile manufacturers have strong incentives to produce vehicles whose emission-related 

components (as well as other components) are durable. The failure of an emission-related 

component in substantial numbers, within a class or category of vehicles, during a vehicle’s 

useful life can give rise to the need for an emission-related recall. Manufacturers seek to avoid 

such recalls, which can be very costly and can also result in reduced customer satisfaction. As a 

result, manufacturers have developed a variety of techniques to evaluate the durability of 

emission-related components, with the goal of ensuring that they remain functional throughout 

the full useful life of the vehicle. Such techniques may include vehicle testing, bench testing of 

selected components, computer modeling, and other methods. In some cases, manufacturers 

provide suppliers with durability-related component specifications and require the supplier to 

attest that the specification is met using whatever data the supplier deems necessary to support 

the attestation. Collectively, these techniques come under the rubric of “good engineering 

judgment.” The manufacturer, rather than the government, decides what information it needs to 

determine that its emission-related components will be durable. Manufacturers have honed these 

techniques over the years, and in the overwhelming majority of cases they work very well. 
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In a Supplemental Notice of Proposed Rulemaking issued on January 17, 2006, EPA discussed 

the issue of component durability and discussed possible options for further rulemaking in this 

area. 71 Fed. Reg. 2843. Option A would allow manufacturers to continue making “good 

engineering judgment” determinations. EPA outlined two other options, B and C, that would also 

require manufacturers to conduct “whole-vehicle testing” of certain vehicles. The problem with 

Options B and C is that they would seek to impose a brand new set of “one-size-fits-all” tests 

across the industry. Clearly, Options B and C would impose significant additional costs on 

vehicle manufacturers, who would be forced to deploy additional human and facility resources to 

conduct time-consuming vehicle tests. In contrast to the certain and substantial costs associated 

with these tests, the benefits of such tests would be negligible. Mandated, cookie-cutter tests are 

unlikely to be particularly effective in assessing component durability; at best, they may produce 

data that is duplicative of information that the manufacturer has already obtained at less cost by 

other methods. 

The CAA gives EPA discretion to determine what types and sources of information 

manufacturers and the Agency may rely on in the course of the vehicle certification process. 

Nothing in the Act requires EPA to mandate uniform tests for every conceivable aspect of 

vehicle certification. Here, manufacturers have a strong track record of producing vehicles with 

durable emission-related components through their use of good engineering judgment. Moreover, 

they have strong incentives to continue doing so. 

Recommendation: In light of the above, we support EPA’s proposal to maintain the “good 

engineering judgment” standard for component durability and refrain from imposing costly and 

unnecessary new tests on the automobile industry. 

Commenter: Afton Chemical Corporation

EPA’s Tier 3 proposal includes “a variety of technical amendments to certification-related 

requirements for engines and vehicle emission standards.” As explained more fully below, Afton 

Chemical’s comments relate solely to those technical amendments, and in particular, the test 

methods and procedures that EPA has proposed for use by vehicle manufacturers to demonstrate 

compliance with the new Tier 3 emission standards. As the Agency should be aware, it has 

worked diligently in recent years to improve the transparency of the vehicle certification process 

under § 206 of the Clean Air Act (“CAA” or “Act”). Afton Chemical has very much appreciated 

those efforts. EPA’s Tier 3 proposal provides a further opportunity for EPA to enhance the 

transparency of the vehicle certification process in accordance with the rulemaking requirements 

of CAA § 206(d).

Afton Chemical markets specialty chemicals for use in motor vehicle fuels and lubricants. One 

of Afton Chemical’s objectives is to market products that improve the performance of fuels and 

lubricants in motor vehicles. For this reason, Afton Chemical has a direct and substantial interest 

in the nature and scope of the test methods and procedures used by EPA to evaluate motor 

vehicle performance. How EPA decides to test motor vehicles under the requirements of § 206 of 

the Act (42 U.S.C. §7525) may impact the design or viability of Afton Chemical’s products. This 

impact can be direct, to the extent that Afton Chemical’s products may potentially influence the 

outcome of the tests, or indirect, to the extent the test methods and procedures impact the way in 
Tier 3 Summary and Analysis of Comments

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which motor vehicle manufacturers design their vehicles to operate. In either case, access to the 

Agency’s test methods and procedures provides Afton Chemical an important tool for evaluating 

its own products. 

When EPA adopted the existing “Tier 2” vehicle emission standards in 1999, Afton Chemical 

(then Ethyl Corporation) sought judicial review of the Tier 2 regulations seeking to ensure that 

EPA developed all test methods and procedures used for motor vehicle “certification” under 

CAA § 206 by rulemaking as specified in CAA § 206(d). Afton Chemical’s legal challenge 

culminated in a decision vacating the Tier 2 regulations and remanding the regulations to EPA 

for further rulemaking. See Ethyl Corporation v. EPA, 306 F.3d 1144 (D.C. Cir. 2002). 

In 2006, following additional public notice and comment, EPA issued new certification 

regulations intended to comply with the court’s mandate in Ethyl Corp. v. EPA. At the same 

time, EPA issued a supplemental notice of proposed rulemaking intended to address one of the 

comments made by Afton during the rulemaking process related to test methods and procedures 

used to establish emission control “component durability” as part of EPA’s certification 

program. As EPA noted at the time, “Afton has raised an important issue.” To address that issue, 

EPA proposed three options for establishing component durability and vehicle manufacturers 

and Afton Chemical thereafter submitted extensive comments on those three options (6). 

In March 2006, Afton Chemical sought judicial review of EPA’s new certification regulations. 

Those petitions for review are being held in abeyance, however, pending EPA action on an 

administrative petition for reconsideration of the then-new certification regulations Afton 

Chemical submitted to EPA a few weeks later. Afton Chemical’s petition addressed three general 

issues: 

1. EPA’s implementation of a procedure using “equivalency factors” that relates various 

proprietary test methods used by automakers to test their vehicles to a “standard road cycle” 

established by EPA as part of the then-new certification regulations. Among other things, Afton 

Chemical expressed concern that (a) the automakers might assert that the equivalency factors are 

confidential business information thereby foreclosing release of equivalency factors to the public 

at large, and (b) the equivalency factors might be of limited value if automakers opted to report 

only a single “worst-case” equivalency factor covering their entire product line (8). 

2. EPA’s treatment of vehicles certified after issuance of the mandate in Ethyl Corp. v. EPA and 

prior to the effective date of the new certification regulations; and 

3. EPA’s failure to adopt by regulation test methods and procedures for assessing the durability 

of vehicle emission control system components, either individually or together as an integrated 

system. 

In April 2007, EPA developed a new durability webpage that can be found at 

www.epa.gov/otaq/regs/ld-hwy/durability. Guidance included on the webpage indicated then 

(and now) that it would provide “more information specifically related to the implementation of 

the new emissions durability rule and the future component durability rule, once it is finalized.” 

Consistent with that statement, in March 2009, EPA posted an initial report containing 

equivalency factors for all certified 2008 model year vehicles. Thereafter (presumably sometime 

during 2010), EPA posted a second report containing equivalency factors for all certified 2008 

model year vehicles. 
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Finally, the court order holding in abeyance Afton Chemical’s legal challenge to the 2006 

certification regulations also required the parties to submit status reports to the court on a rolling 

90 day basis. Since the court’s order, twenty-seven status reports have been submitted to the 

court, the most recent on April 1, 2013. In all of those reports, EPA represented that it was 

continuing its examination of “the administrative record and comments regarding Afton’s 

administrative Petition for Reconsideration” to determine whether it “has merit” and that the 

Agency would “make a final determination whether or not to grant that administrative petition as 

soon as is practicable” (14). 

EPA’s Tier 3 Proposal as It Relates to Vehicle Certification under CAA § 206: EPA’s Tier 3 

proposal includes a number of proposed revisions to the pre-existing CAP 2000 vehicle 

certification regulations. One such proposed regulation is 40 C.F.R. § 86.1823-08(g), pertaining 

to emission component durability testing. EPA has proposed adoption of the following 

regulatory text: 

(g) Emission control component durability. The manufacturer shall use good engineering 

judgment to determine that all emission-related components are designed to operate properly for 

the full useful life of the vehicles in actual use. 

Despite the fact that the foregoing language exactly matches the first of the three options EPA 

proposed in 2006 in its supplement notice to address Afton Chemical’s concerns about the test 

methods and procedures used to demonstrate component durability, EPA nowhere addresses (a) 

why the Agency has apparently opted to adopt the first of the three options for component 

durability proposed in 2006 (and presumably rejected the other two options (or any others that 

might have been adopted)); (b) Afton Chemical’s administrative petition for reconsideration 

(which addresses the same issue), or (c) whether the proposed regulatory text is intended to 

provide EPA’s response to Afton Chemical’s reconsideration petition (as it unavoidably does) 

(16). 

As previously acknowledged, EPA has substantially improved the transparency of the vehicle 

certification program and Afton Chemical fully supports the Agency’s efforts in that regard. The 

Tier 3 proposal provides EPA another opportunity to enhance transparency by adopting 

appropriate test methods and procedures for establishing the durability of emission control 

system components by rulemaking as required by § 206(d) of the Act (17). Afton Chemical 

therefore requests that the Agency address this important issue (including the long-pending 

administrative petition for reconsideration) as part of its continuing assessment of the Tier 3 

proposal (18). 

6 - See id. at 2847-2848. The comments submitted by Afton Chemical and automaker associations can be 

found at www.regulations.gov in docket: EPA-HQ-OAR-2002-0079. Afton Chemical incorporates by 

reference (as if included directly in these comments) all of the documents contained in the foregoing 

docket.

8 - See www.regulations.gov: docket EPA-HQ-OAR-2002-0079-0033, pp. 3-7.

14 - See, e.g., Afton Chemical Corporation v. Environmental Protection Agency, Case Nos. 06-1095 and 

06-1096, Status Report (April 1, 2013).

16 - EPA states only that “[m]anufacturers and catalyst suppliers perform detailed studies evaluating the 

cost and emission control performance of aftertreatment systems.” Draft Regulatory Impact Analysis: 

Tier 3 Motor Vehicle Emission and Fuel Standards (March 2013) (EPA-420-D-13-002), p. 1-26. As 
Tier 3 Summary and Analysis of Comments

6-65

Afton Chemical noted in comments responding to EPA’s supplemental notice concerning emission 

control system component durability, “[i]f good engineering judgment is to be the test for component 

durability, then EPA has to specify in its regulations what the test entails with sufficient specificity that 

interested members of the public will know how good engineering judgments are made by each 

automaker and can potentially replicate the exercise of engineering judgment in any particular case.” See 

www.regulations.gov: docket EPA-HQ-OAR-2002-0034, pp. 3-4.

17 - Several other provisions in EPA’s Tier 3 proposal also identify “good engineering judgment” as the 

metric for establishing the durability of emission-related components, including those that control 

evaporative and re-fueling emissions. See, e.g., 40 C.F.R. § § 86.1810.1(c), 86.1824(h) and 86.1825-

08(h). As with EPA’s proposed revision to 40 C.F.R. § 86.1823(g), these other provisions fall short of the 

rulemaking directive in § 206(d) of the Act (as Afton has explained in its administrative petition for 

reconsideration and related comments).

18 - The passage of time has obviated the need for EPA to address the second issue addressed in Afton 

Chemical’s administrative petition for reconsideration so Afton Chemical formally withdrawals that part 

of its petition. See www.regulations.gov: docket EPA-HQ-OAR-2002-0033, pp. 8-15. Regarding the first 

issue addressed in Afton Chemical’s petition, release by EPA of equivalency factors for all vehicles in the 

manner employed by EPA (i.e., reporting equivalency factors for each vehicle and each catalytic 

converter on each vehicle) addresses most, but not all of Afton Chemical’s concerns about 

implementation of the equivalency factor procedure. Afton Chemical notes, for example, that EPA has 

not updated its durability webpage to include any equivalency factors other than those for the 2008 model 

year even though EPA represents on its webpage that it would update equivalency factors on a semiannual basis. See http//www.epa.gov/otaq/regs/ld-hwy/durability (“The equivalency factor must be 

provided by manufacturers of light-duty vehicle, light-duty trucks and heavy-duty vehicles each model 

year and will be published semi-annually on this site.”).

Our Response:

In the Tier 3 proposal, EPA included purely administrative changes to the component 

durability regulations for vehicle certification to remove regulatory citations from the text. The 

component durability regulations referenced older versions of the component durability 

regulations promulgated in 1999. In the Tier 3 proposal, EPA’s intent was merely to remove the 

1999 citations and replace them with “plain language” describing the same, unchanged 

regulatory requirements. That proposed change may have inadvertently led to the mistaken 

impression that EPA was proposing a final decision on a separate rulemaking proposal, the 

component durability proposal, published in 2006 (71 FR 2843, Jan. 17, 2006). Given the 

confusion regarding the purpose and effect of the proposed changes, and our intent not to make 

any substantive changes or decisions related to these provisions in this rulemaking, we are not 

finalizing the proposed revisions.

As noted in comments, Afton Chemical has also submitted a petition for reconsideration 

for the 2006 Durability Final Rule (71 FR 2810, Jan. 17, 2006). The Tier 3 rule does not address 

that petition and does not include a response to that petition for reconsideration. EPA will 

finalize its response to that petition separately.

6.2.2. Other

6.2.2.1. Fuel Economy Labeling
Chapter 6: Regulatory Streamlining and Technical Amendments

6-66

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Current vehicle fuel economy labels include a smog rating ranging from 1 to 10. Vehicle labels 

need to convey complex information in a simple manner enabling an equitable comparison of 

vehicle attributes by new vehicle buyers. At no time should two differing smog rating scales be 

used, as it will only confuse consumers by demonstrating a false comparison. Current smog 

scales should be maintained until every vehicle manufactured is certified to the new Tier 3 

standards, at which time, all labels can be transitioned to an adjusted smog scale.

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Under Fuel Economy Labeling: We request comment on applying smog ratings to TZEV 

vehicles; in particular, we request comment on any appropriate differentiation of TZEV vehicles, 

such as assigning different smog ratings based on the particular SULEV exhaust emission 

standards or the allowance value for different all-electric range values. We request comment on 

these and other alternative approaches to revising the specifications for the smog rating on the 

fuel economy label.

We also request comment on whether one or more transition rating scales would be appropriate 

to gradually adjust the smog rating scale as the fleet average standards become more stringent.

With respect to the Smog Ratings for TZEVs, we recommend EPA work with industry to 

develop an appropriate method that will account for real-world emissions based on factors such 

as exhaust certification level and all-electric range. We believe that the appropriate accounting 

for real-world emissions of TZEV should be addressed in BOTH the smog ratings AND the 

value used to calculate fleet average NMOG+NOx.

With respect to transition to different smog ratings, the intent of smog ratings are to inform 

consumers. Consequently, consistency is very important. It is possible, and in fact likely, that 

two vehicles identical in all respects except MY, will have different smog ratings for no other 

reason than changes to the scoring. Such discrepancies lead to confusion and lead customers to 

ignore the label all together or incorrectly believe that a newer cleaner vehicle has the same 

emissions as an older vehicle. While it might be necessary to make changes to the label at some 

point, we recommend severely limiting those changes. 

Our Response:

In addition to the current rating scale, which will apply through MY 2017, EPA is 

finalizing one interim scale between now and MY2025. Though the standards will become more 

stringent annually, we believe it is important to strike a balance between maintaining consistency 

of the smog rating scales across multiple model years and targeting the midpoint of the smog 

rating to be at the current fleet average standard. An interim scale will allow for both. EPA 
Tier 3 Summary and Analysis of Comments

6-67

understands that the first model year of a new rating scale may need additional explanation to 

ensure consumers understand that the rating scale has changed. We intend to help communicate 

these changes via fueleconomy.gov and EPA’s Green Vehicle Guide.

EPA plans to develop guidance for smog ratings for TZEV vehicles in its annual fuel 

economy guidance letter. Therefore we are not finalizing a smog rating for California TZEV 

vehicles at this time.

In addition to the current rating scale, which will apply through MY 2017, EPA is 

finalizing one interim scale between now and MY2025. Though the standards will become more 

stringent annually, we believe it is important to strike a balance between maintaining consistency 

of the smog rating scales across multiple model years and targeting the midpoint of the smog 

rating to be at the current fleet average standard. An interim scale will allow for both. EPA 

understands that the first model year of a new rating scale may need additional explanation to 

ensure consumers understand that the rating scale has changed. We intend to help communicate 

these changes via fueleconomy.gov and EPA’s Green Vehicle Guide.

6.2.2.2. Vehicle Labeling

What Commenters Said:

Commenter: Ford Motor Company

Ford ... recommends that the requirement for vehicle ULSD labels be removed. Such vehicle 

labeling would be unnecessary for the same reasons that the ULSD pump label is no longer 

needed. 

Our Response:

EPA has already modified §86.1807-01(h) to discontinue the vehicle labeling 

requirement related to ULSD for model year 2014 and later vehicles subject to chassis-based 

standards (77 FR 34146, June 8, 2012). We proposed in the Tier 3 NPRM to adopt this same 

provision for vehicles equipped with engines certified to the engine-based standards in 40 CFR 

part 86, subpart A. We are including this provision without modification in the final rule.
Tier 3 Summary and Analysis of Comments

7-1

7. Costs

What We Proposed:

The comments in this chapter correspond to Section VII of the preamble to the proposed 

rule and address the estimated costs of the program. Summaries of the comments received and 

our responses to those comments are located below.

7.1. Costs of the Vehicle Standards

What Commenters Said:

Commenter: Consumers Union

In their comments, the Consumers Union states that, in addition to the tremendous public health 

benefits, vehicle owners will also see direct financial benefits from the proposed rule. The 

Consumers Union argues that lowering the sulfur content in gasoline cleans up exhaust from 

older cars, reduces corrosion of emissions control systems for existing vehicles and increases 

the lifespan of catalytic converters which can cost hundreds to thousands of dollars to replace. 

Commenter: Peoples Republic of China

In their comments, the Peoples Republic of China had a somewhat opposite view stating that, 

since the useful life is being increased to 150,000 miles, manufacture costs will increase due to 

the need for more durability testing—costs which will result directly in the rise of the sales 

price of each vehicle. Their comments went on to recommend that the useful life under Tier 3 

be the same as that under Tier 2. 

Our Response:

We agree with the comment that reducing the sulfur level of gasoline will clean up 

exhaust from the majority of older cars as observed in our Tier 2 sulfur test program and 

analysis (see the final RIA). However, current sulfur levels have not demonstrated a 

deleterious impact on system durability and, therefore, we have not included any change in 

catalytic converter lifespan or included any such savings in our cost analysis. 

Regarding the comment from the People’s Republic of China, we have carefully 

considered the vehicle costs associated with the Tier 3 standards and present those costs in 

detail in Chapter 2 of the final RIA.

What Commenters Said:

Commenter: Emissions Control Technology Association (ECTA)
Chapter 7: Costs

7-2

In their comments, the Emissions Control Technology Association (ECTA) states their belief 

that EPA’s track record in estimating future technology costs has traditionally been shown to be 

very conservative (SAE 2002-01-1980). ECTA goes on to state their belief that

The Tier 3 hardware cost estimates are also on the high side. As an example, ECTA notes that 

they are aware of advanced substrate developments being tested with customers that will 

decrease precious metal usage possibly 10-20% below current levels. 

Commenter: International Council on Clean Transportation (ICCT)

In their comments, the International Council on Clean Transportation (ICCT) states that the 

costs to comply are modest and likely overstated in the proposal [EPA-HQ-OAR-2011-0135-

4304-A1, p. 1]. ICCT also states that major advancements have occurred in vehicle emission 

control technology: catalysts have improved dramatically; fuel injection is more precise;

feedback of actual air/fuel ratio is faster; software algorithms to predict air/fuel ratio have 

improved; drive-by-wire systems allow air and fuel to be changed simultaneously; and,

development of initial idle retard for cold starts can bring the catalyst above light-off 

temperature before the initial 20-second idle is done. ICCT claims that, as these and other 

improvements are primarily due to better software algorithms, meeting the vehicle standards 

will be easier and will cost much less than assumed in the proposed rule. ICCT highlights their 

own analyses which found that catalyst precious metals will cost only about a third as much as 

estimated in the draft RIA and that optimized close-coupled catalyst, optimized thermal 

management, secondary air injection, and hydrocarbon adsorbers will not be needed on the vast 

majority of vehicles and/or will cost much less than estimated in the draft RIA. 

ICCT also points to recent research by Honda and Johnson Matthey showing platinum group 

metal (PGM) usage could be reduced by 25% with respect to current Tier 2 Bin 5 levels and 

still provide LEVIII SULEV30 compliance (i.e., Tier 3 Bin 30) by using an improved layered 

catalyst and improved oxygen storage capacity (OSC). ICCT also notes research by Umicore 

in which Umicore stresses the importance of a combined NMOG+NOx standard as being less 

demanding than separate NMOG and NOx standards ICCT also provided their assessment that 

a 20% increase in PGM loading is the most that would be required for Tier 3.

ICCT also states that the proposal appears to place too much emphasis on early LEVII-SULEV 

vehicles, some of which used secondary air injection or HC adsorbers to ensure compliance. 

ICCT argues that these were the first vehicles to comply with lower emission standards and 

they were relatively low volume making it easier and cheaper for manufacturers to add existing

hardware than to invest the engineering resources to fully optimize precise air/fuel control and 

fast light-off strategies, or to develop new hardware. ICCT adds that many manufacturers were 

able to meet the LEVII-SULEV standards without such additional hardware, even on their first 

attempt. 

Commenter: Manufacturers of Emission Controls Association (MECA)

In their comments, the Manufacturers of Emission Controls Association (MECA) states general 

agreement with the proposed cost estimates but, given that the Tier 3 vehicle cost estimates 
Tier 3 Summary and Analysis of Comments

7-3

were assembled approximately two years before the proposal was publicly released, MECA 

encouraged an update to the costs with the latest projections from the automobile industry and 

emission control industry. MECA states their belief that a number of factors will allow 

projected Tier 3 compliance costs to be lower than the proposed estimates. MECA notes that 

these factors include available and continued improvements in three-way catalyst technology, 

the additional flexibility of meeting a combined NMOG+NOx Tier 3 standard versus meeting 

individual NMOG and NOx emission standards, and the trend of engine/vehicle downsizing 

that auto manufacturers will use to comply with the future fuel economy/greenhouse gas 

emission standards. 

Commenter: Sierra Club

In their comments, the Sierra Club argued that the proposal had demonstrated that the 

substantial increase in stringency of the proposed rule does not have correspondingly high 

costs. The Sierra Club suggested that this is because federal fleets already are demonstrating 

actual emissions performance much cleaner than the level to which they are certified. The 

Sierra Club also argues that not every technology will be required on all vehicles to meet the 

proposed standards, and only the most difficult powertrain applications will require very 

expensive emissions control solutions. 

Our Response:

EPA agrees with these commenters that our proposed vehicle cost estimates 

used dated information and the estimated vehicle costs presented in the proposal were 

inappropriately high. For the final rule, as described fully in Chapter 2 of the final RIA, we 

have updated our vehicle cost estimates. In doing so, we have incorporated information from 

ICCT’s study (SAE 2013-01-0534), ICCT’s docket comments on the proposal, and a Umicore 

study (SAE 2012-01-1245). As a result, the vehicle cost estimates in the final rule and, in 

particular, the catalyst loading costs are considerably lower than in the proposal. Further, we 

consider the final estimates to be much more transparent in that they provide much greater 

detail behind the estimates, and we consider them far more robust given the greater level of 

supporting information

Regarding MECA’s statement that engine downsizing in the context of green house gas 

standards would help reduce Tier 3 costs, we agree and have accounted for that effect by using 

the EPA-projected fleet mix resulting from the 2017-2025 GHG standards. That fleet mix 

contains a predominance of gasoline I4 engines which are the least costly engines at meeting 

Tier 3 emissions standards. The fleet mix used in the final rule and how it differs from the 

proposed rule is discussed in Chapter 2.7 of the final RIA.

Regarding the comments from the Sierra Club, we agree that some vehicles are 

demonstrating compliance with the Tier 3 standards today and have incorporated that fact into 

the final vehicle cost analysis. We also agree that not every technology will be required on all 

vehicles and have incorporated that fact into our analysis via the penetration (or application) 

rates presented in Tables 2-16 and 2-17 of the final RIA.
Chapter 7: Costs

7-4

7.2. Costs of the Fuel Program

What Commenters Said:

Commenter: International Council on Clean Transportation (ICCT)

There are two additional very important points. First, reducing gasoline sulfur will result in 

large emission reductions not just from future Tier 3 vehicles, but also from the entire in-use 

fleet. The impacts of sulfur on older vehicles, in grams/mile, are fully as large as on Tier 3

vehicles, if not larger. As most of the sulfur impacts on catalysts are reversible, reducing 

gasoline sulfur will result in immediate and very large reductions of in-use emissions. 

Second, analyses of catalyst precious-metal loadings and cost are generally done without 

considering changes in fuel sulfur. Reducing gasoline sulfur will enable reductions in catalyst 

precious-metal loadings, further reducing the cost of compliance and offsetting much of the 

cost of reducing fuel sulfur. 

I also want to emphasize that the impact of sulfur on older vehicles in grams per mile are fully 

as large as on Tier 3 vehicles, if not larger. And as most of the sulfur impacts are reversible, 

reducing the sulfur will result in immediate and very large end use emission reductions.

Commenter: PBF Energy Inc.

PBF has reviewed and evaluated the proposed rule to control Air pollution from Motor 

vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards. PBF is concerned that this 

regulation will place a large economic burden on refiners who must modify facilities to meet 

the proposed new fuel standards. 

Commenter: State of Utah

In moving forward, EPA must minimize disruption and costs to refineries, costs which likely 

will be passed on to consumers. Manufacturing Tier 3 gasoline will require significant 

investments by Utah’s petroleum refineries. 

Our Response:

As shown in Sections V and VII of the preamble to the final rule, we believe that the 

costs imposed is reasonable in light of the environmental benefits the Tier 3 program provides 

and it is therefore a reasonable action for EPA to require under our statutory authority. As also 

discussed in Chapter 5.5 of this Summary and Analysis of Comments document, we designed 

the program with considerable flexibility to minimize the cost and burden of complying with 

the standards.
Tier 3 Summary and Analysis of Comments

7-5

7.2.1. Impact of the Sulfur Standard (on Refinery Closures, Price Spikes, Fuel 

Shortages)

What Commenters Said:

Commenter: Advanced Engine Systems Institute (AESI)

During the Tier 2 rulemaking process, petroleum industry executives predicted dire outcomes if 

that rule were to go into effect, including refinery closures, price spikes, and fuel shortages.

Some stated it melodramatically, ‘For some refiners, EPA’s proposed regulation will be the 

straw that broke the camel’s back. Facilities will close and jobs will be lost.’

Since then, refining activity has remained fairly constant, while shortages and price spikes 

driven by de-sulfurization requirements failed to materialize. In fact, an analysis done in late 

2007 by experts from the Federal Reserve Bank of Dallas found no discernible effect on 

gasoline prices of the fully phased in Tier 2 sulfur requirements. And studies show that Tier 2 

benefits in ozone reduction alone far outweighed oil industry costs of implementation.

For the proposed Tier 3 rule, the oil industry is again claiming that their costs of making sulfur 

reductions do not justify the benefits to the public’s health and the economy. Yet the oil 

industry’s most recent study for the Tier 3 proposal shows that no refineries will be closed or 

become uneconomic to operate, and it fails to accurately model the actual rule as proposed.

Commenter: Environmental Defense Fund (EDF)

Furthermore, erroneous claims of high costs by API are all too familiar. API made similar 

claims about the Tier 2 program and opposed a national program to address sulfur from 

vehicles and instead advocated for a less protective regional approach, suggesting western 

states had good air quality and that there would be only modest benefits of a national program 

(115). Yet, in recent testimony to EPA, API acknowledged that the Tier 2 program, “yielded 

measurable environmental benefits. The air quality benefits of the Tier 2 program are still being 

realized’ (116). 

115 - Environmental Protection Agency, Tier 2 Motor Vehicle Emission Standards and Gasoline Sulfur 

Control Requirements: Response to Comments, December 1999: 13-5.

116 - American Petroleum Institute, Testimony by Patrick Kelly at the EPA Philadelphia Public Hearing 

(Apr. 24, 2013).

Our Response:

We received comments that disputed claims of the refinery industry on the impacts of 

the sulfur standards. We agree with the commenters that the oil industry has made very 

dramatic claims in the past regarding refinery closures and shortfalls in product availability, 

and the most dramatic claims occurred in response to nonroad and highway diesel fuel 
Chapter 7: Costs

7-6

standards. After the first Baker and O’Brien cost study which made similar conclusions 

associated with low sulfur and low RVP standards prior to our Tier 3 NPRM, we compared 

what actually transpired to diesel fuel supply and refinery closures after 2006 when the 

highway diesel fuel sulfur standards took effect to the dramatic predictions made by Baker and 

O’Brien and provided our comparison in Chapter 5 of the draft RIA for the NPRM. Our 

findings were that none of the dire predictions made by Baker and O’Brien with respect to 

diesel fuel had occurred. We also note that the revised Baker and O’Brien cost study for Tier 3 

gasoline, which solely evaluated the cost of lower sulfur gasoline, neither forecasted any 

refinery closures nor reductions in the supply of gasoline like the first Baker and O’Brien study.

7.2.2. Cost (Average Cost and Marginal Cost, Such as 6 – 9 c/gal)

7.2.2.1 Average Cost

What Commenters Said:

Commenter: Natural Resources Defense Council (NRDC)

API has a history of inflated cost claims. A review of several clean fuels regulations finds that 

API estimates have been 3.6 to 6.4 times higher than actual observed price changes. 

The API high cost estimates have the potential to raise concerns of industry investors, and some 

refining companies are backing away from the API estimates to present more realistic figures.

For example, Valero Energy, which is the largest independent refiner in the U.S., recently told 

a group of financial analysts that its Tier 3 compliance will cost to $300 to $400 million. A 

finance expert colleague of mine at NRDC used the EPA’s marginal cost assumptions and 

found that the $400 Valero cost claim would equate to a compliance cost of approximately .6 

cents per gallon, more than 10 times less than the API high estimate.

For Valero, the .6 cent per gallon translates into annual costs of about $95 million, or just two 

percent of the four and a half billion in pretax earnings that the company made on refining in 

2012. While Valero and other companies point out the cost of compliance is minimal, API 

continues to inflate costs. Regulatory cost inflation is part of their history. By exaggerating 

costs, API has attempted to scare consumers into potential large gas price increases at the 

pump. 

The reality is that these large increases don’t appear. According to a peer review report by 

EPA, API’s estimates of compliance costs for previous clean fuel regulations adopted in the 

1990s have been 3.6 to 6.4 times higher than the actual observed price changes. Similarly, a 

recent study by Navigant Economics found that the Tier 2 gasoline sulfur regulations, which 

API estimated would cost about three cents a gallon, have had no discernible impact on retail 

prices.

Commenter: Navigant Economics
Tier 3 Summary and Analysis of Comments

7-7

First, there are serious flaws in the approach employed by Baker and O’Brien on behalf of the 

American Petroleum Institute to estimate the compliance cost to refineries. Second, I’ve 

examined EPA’s cost benefit analysis. It comports with economic logic and best practices, and 

it validates our conclusions. Third, we examined the effects of the Tier 2 sulfur rule on the 

price of gasoline and found little to no impact suggesting the Tier 3 effect will be negligible.

So going to my first point on the flaws in the Baker and O’Brien approach, there are several, 

but today I just want to address three. Baker and O’Brien failed to account for averaging and 

trading of credits, which reduces the compliance costs to refineries. As EPA explained, 

refineries with pre and post treaters are able to achieve further sulfur reductions below the 10 

parts per million standard at a relatively low incremental cost, and sell credits to refineries who 

would otherwise be faced with grass roots investments.

Averaging and trading reduces EPA’s estimated compliance cost from .97 cents per gallon to 

.79 cents per gallon, a reduction of nearly 20 percent with averaging in trading. Between eight 

and 25 high-cost refineries out of 11 would prefer to consume credits than to upgrade their 

facilities. Baker and O’Brien’s mistaken assumption that those high-cost refineries reduce the 

sulfur content of their gasoline they produce to 10 parts per million severely inflates their 

compliance cost estimates.

Second, Baker and O’Brien assume without support that the refinery with the highest cost of 

compliance will set the price of gasoline. However, if this were true, then the profits of the 

refinery industry, defined as the difference between the marginal cost and the average cost per 

gallon, would be four to seven cents, at which point the refiners should endorse Tier 3. Given 

the refiners’ opposition, it seems that Baker and O’Brien’s logic is faulty.

Third, Baker and O’Brien’s estimated capital cost for a grass roots FCC post treater is not 

reasonable according to companies that construct or install desulfurization units. Indeed, Baker 

and O’Brien’s capital cost estimates are between two and four times higher than industry 

benchmarks. Baker and O’Brien states that their estimates were based on actual installation for 

the Tier 2 program, but as EPA explains, a grass roots FCC post treater installed for Tier 2 

would remove about 10 times more sulfur than one installed for Tier 3, and, thus, would have 

significantly higher capital costs. Correcting this one defect in the Baker and O’Brien study 

causes their cost estimates to come into alignment with those of MathPro and of EPA.

Thank you for the, I guess, the support for our cost analysis. But if you could just spend just a 

moment, because you were cut a little short. So what are the main differences between, you 

know, our one cent a gallon and the six to nine cent estimate from Baker and O’Brien?

So I think the points that I rattled off were the main drivers. One is this conflation of the 

average and the marginal. I think that what -- when you actually saw for the average of the 

Baker and O’Brien, you don’t get that big of a divergence. You get something like one versus 

two.

But even there, the difference can be entirely explained away with just one change, and that’s 

this capital cost component of these treaters. And the way that we tried to ascertain that it was 
Chapter 7: Costs

7-8

exaggerated was by interviewing actual providers of these equipments, these types of 

equipment and founding out whether their costs were reasonable. And they told us they 

weren’t.

Commenter: Natural Resources Defense Council (NRDC)

API’s cost estimates for Tier 3 are inconsistent with API’s own members, which estimate costs 

as either immaterial to their business or less than a penny a gallon. 

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

We recognize that reducing the sulfur content of fuel will have a cost. However, as EPA details 

in the proposed rule, these costs have been exaggerated by the petroleum industry (66). Indeed, 

as a general matter, petroleum product prices are due primarily to changing global crude oil 

prices. The compliance costs of the sulfur reductions contained in the proposed rule will not 

have an appreciable effect on the price of gasoline at the pump. 

In the proposed rule EPA found that the cost of compliance with the fuel standards will be an 

average of 0.89 cents per gallon (67). The Baker and O’Brien study (API) found a 1.9 cent per 

gallon average increase from Tier 2 (6-9 cents marginal cost with no RVP change) (68). In 

contrast, the MathPro study for the International Council on Clean Transportation (ICCT) 

found a 0.8 to 1.4 cent per gallon increase from Tier 2 (69). In the proposed rule, EPA’s 

analyses were closer to the MathPro estimates, and exposed the invalid assumptions of the 

Baker and O’Brien study (70). It is extremely unlikely that a small (1 cent or less) increase in 

refining costs would be passed on to consumers in an increased gasoline price (71).

In short, both EPA’s data in the proposed rule and the Navigant study demonstrate that the 

overall cost impact of reduced sulfur will be very low on an average per-gallon basis, and 

significantly lower than the benefits of the rule. Navigant states that Tier 2 had no statistically 

significant impact on gas prices after controlling for cost of crude oil, refinery margins and 

other factors, and Tier 3 would impose only half the average cost of Tier 2 (approximately one 

cent per gallon versus 2 cents). Therefore, as noted above, it is very likely the retail pump 

impact of the reduced sulfur requirements will be close to or at zero. Even the Baker and 

O’Brien study, which both EPA and Navigant has discredited for a number of overestimates of 

cost, still found that no refinery shutdowns are projected from the reduction in sulfur proposed 

under the rule. The benefits of the rule far outweigh the costs, and the reductions in sulfur will 

be a crucial component of allowing the OEMs to achieve the required reductions in criteria 

pollutants.

65 - The (octane) grade weighted (pool average for US (excluding California) would be closer to 27 

ppm. Survey can be purchased from the Alliance website www.autoalliance.org. 

66 - 78 Fed. Reg. 29908 at 29972-29979 (May 21, 2013). 

67 - 78 Fed. Reg. 29908 at 29972 (May 21, 2013). 

68 - See March 2012 addendum to the original July 2011 Baker and O’Brien study. This was analyzed 

by the Navigant study. 
Tier 3 Summary and Analysis of Comments

7-9

69 - Id. 

70 - EPA cited to the Navigant study which found that Baker and O’Brien cost predictions have been 

inflated in the past (e.g., cost of reducing sulfur in diesel fuel was significantly less than predicted). 78 

Fed. Reg. 29908 at 29978 (May 21, 2013). EPA also points to Navigant’s data showing that the Baker 

and O’Brien study does not account for reductions in cost from averaging and trading. In addition, the 

Baker and O’Brien study also has other logical flaws, such as erroneously large capital cost assumptions 

and a lack of quality data about the individual U.S. refiners, both of which were noted by EPA. 

Navigant believes that the Baker and O’Brien study exaggerates the costs by a factor of 2 to 1. EPA and 

Navigant note that estimated capital cost for new FCC naphtha desulfurization unit used in the Baker & 

O’Brien study is not reasonable. 78 Fed. Reg. 29908 at 29978 (May 21, 2013). Navigant notes that 

differences in the refinery model methodologies (i.e. individual refinery versus PADD-based) between 

the Baker and O’Brien and Math Pro studies is not enough to account for their varying cost estimates. 

Instead, Navigant found that different assumptions about capital costs account for most of the difference 

in cost estimates. 

71 - See also recent MathPro Tier 3 testimony at the EPA public meeting.

Commenter: American Fuel & Petrochemical Manufacturers (AFPM)

A Baker and O’Brien analysis estimates that a gasoline sulfur content reduction will cost 

refiners $10 billion in capital costs, and $2.4 billion per year in operating costs, increasing the 

cost of producing gasoline by six to nine cents per gallon. 

Commenter: American Lung Association

Other Analyses Support EPA’s Findings that Standards Have Very Low Cost for Consumers: 

Two independent studies support EPA’s conclusions that the refining cost associated with Tier 

3 sulfur standards will be very low compared to the benefits. In 2011, MathPro, a consulting 

firm specializing in economic analysis of petroleum refining and related industries, 

commissioned by the International Council for Clean Transportation, found that the per-gallon 

refining cost of a Tier 3 program with a 10 parts per million sulfur standard would be 1.4 cents 

(47). 

In 2012, Navigant Economics, commissioned by the Emissions Control Technology 

Association, estimated the cost of low sulfur gasoline standard would be about one cent per 

gallon. This estimate is closer to EPA’s and MathPro’s estimates rather than the higher cost 

claims from the oil industry (48).

47 - MathPro. Refining Economics of a National Low Sulfur, Low RVP Gasoline Standard: A study 

performed for The International Council for Clean Transportation. MathPro Inc: Maryland, 2011. 

Available at 

http://www.theicct.org/sites/default/files/publications/ICCT04_Tier3_Report_Final_v4_All.pdf

48 - Schink GR, Singer HJ. Economic Analysis of the Implications of Implementing EPA’s Tier 3 

Rules: Prepared for the Emissions Control Technology Association. Navigant Economics: Washington 

D.C., 2012. Available at http://www.ectausa.com/061212-Economic-Analysis-of-the-Implications-ofTier-3-Sulfur-Reduction-Finalembargoed.pdf

Commenter: American Petroleum Institute (API) and the Association of Fuel & 
Chapter 7: Costs

7-10

Petrochemical Manufacturers (AFPM)

Reducing gasoline sulfur to an average of 10 parts per million is expensive. Research API 

shared with the Agency shows nearly $10 billion in capital costs. The annual compliance cost 

is about $2.4 billion, or six to nine cents per gallon in marginal costs. EPA should not consider 

these costs in a vacuum. Refiners need to balance these expenses with the cumulative costs of 

other Federal and States regulations.

EPA: Did you say that the annual cost from your study was $2.4 billion? 

API: The annual compliance costs. That includes the – it is the annual cost of compliance and 

includes capital recovery.

EPA: And so what is that in terms of cents per gallon then because that’s the average cost 

then?

API: That’s a total cost, the $2.4 billion. And it equates to a six to nine cent per gallon 

marginal cost in most markets. Does that answer your question?

EPA: I guess – well, what is the $2.4 equate to in terms of an annual – in terms of cent per 

gallon?

API: In marginal costs, it would be six to nine.

EPA: Do you have an average cost?

API: We didn’t do an average cost. While average cost is an important factor, in commodity 

markets, when all of the demand is needed for that commodity, the marginal cost is very 

relevant in setting the market price. And so, therefore, we looked at the marginal cost because 

of its importance to the marketplace.

EPA uses a cost estimate based on average cost that ignores the important role that marginal 

cost plays in gauging the market response to the regulation. EPA should not consider these 

costs in a vacuum. Refiners need to balance these costs with the cumulative cost of other 

Federal and States regulations.

Commenter: Attorney General of Connecticut, et.al; Attorney General of New York, et.al

Indeed, EPA concluded that “[t]he proposed fuel standards are projected to cost on average less 

than one cent per gallon of gasoline.” 78 Fed.Reg. at 29,827. 

Commenter: Chevron Products Company

We believe that EPA has underestimated the cost and complexity of the changes which will be 

required in the refining industry to achieve this reduction. EPA’s economic impact analysis 

relies entirely on the national average cost increase for gasoline production, instead of the 

marginal or incremental cost of supply as proposed by Baker and O’Brien (1). The incremental 

cost of supply is usually correlated with market price effects when demand must be met with 

more expensive sources of supply. Therefore, using the incremental value is more 

representative of the true societal cost than using the average. By using the national average 

cost increase, EPA is underestimating the true cost of the Tier 3 program. 

1 - Baker & O’Brien, ‘Potential Supply and Cost Impacts of Lower Sulfur, Lower RVP Gasoline’, 2011
Tier 3 Summary and Analysis of Comments

7-11

Commenter: Emissions Control Technology Association (ECTA)

We agree with EPA’s methodology for estimating the cost that the refining industry will incur 

to comply with the sulfur content requirement of Tier 3. We also agree with EPA’s estimate 

that the average cost of compliance for the refining industry is only 0.89 cents per gallon (16). 

We believe EPA’s estimated costs are reasonable for two reasons as described below. 

It is also noteworthy that EPA’s average cost per gallon estimates comported with those of 

Mathpro (0.8 cents), further validating its cost model (20). 

Based on a study by Baker O’Brien sponsored by the American Petroleum Institute, the 

refining industry cost estimates implies that the average cost of compliance would be 2.12 cents 

per gallon or more than double EPA’s estimate of 0.89 cents per gallon (24). We believe that 

EPA’s estimate is far more reliable than the refining industry’s estimate for three reasons. 

First, Baker & O’Brien assumed an after-tax ROI for capital invested for the hydrotreaters and 

hydrogen plants of 10%, which is unreasonably high. EPA assumed before-tax ROI of 7% (25). 

This before-tax ROI is equivalent to an after-tax rate of return of approximately 5.2 %, and it is 

consistent with the rates used by EPA in related matters (26). To be fair, Baker & O’Brien’s 

higher rate of return may be closer to what refiners use when evaluating conventional refinery 

investment opportunities (27). However, EPA correctly uses a lower 7% ROI when estimating 

the social costs of regulations. In other words, the EPA’s 7% before-tax rate of return is 

effectively a social discount rate; the same value is used by EPA to discount future benefits 

from environment regulations. Merely changing Baker & O’Brien’s assumed ROI to reflect the 

perspective of society (rather than private industry) reduces its estimated average compliance 

costs from 2.12 to 1.58 cents per gallon. 

20 - EPA Proposal, Fed. Reg. at 29977.

24 - Id. at 29977.

25 - Id. at 29978.

26 - See, e.g., EPA, Regulatory Impact Analysis: Heavy Duty Engine and Vehicle Standards and 

Highway Diesel Fuel Sulfur Control Requirements, EPA420-R-00-026, Dec. 2000.

27 - Mathpro, Refining Economics of National Low Sulfur, Low RVP Gasoline, Oct. 2011, at p. 13 

(hereinafter Mathpro Study).

Commenter: Environmental Defense Fund (EDF)

The fuel standards in the Tier 3 proposal are cost-effective. EPA estimates that the cost to 

refiners of reducing the sulfur in gasoline to an average of 10 ppm will be 0.89 cents per gallon 

averaged over all gasoline. 

Even if there were no ABT program, or no refiners decided to participate in the program, EPA 

estimates that the fuel costs would still only be 0.97 cents per gallon on average. Moreover, a 

study by Navigant Economics projects that these costs will not be passed on to consumers 

(106). 
Chapter 7: Costs

7-12

The International Council for Clean Transportation: The International Council for Clean 

Transportation (ICCT) commissioned a study by MathPro in 2011, building upon and updating 

a 2009 MathPro study commissioned by the Alliance of Automobile Manufacturers. The ICCT 

study analyzed the economic impact of a 10 ppm sulfur limit for all gasoline and found that the 

cost of lower sulfur standards to oil refiners would be 0.8–1.4 cents per gallon (107). MathPro 

estimates that $3.9 billion would need to be invested to meet low-sulfur standards and that the 

annual refining costs would be $1.5 billion. These estimated costs are very close to EPA’s 

estimates. 

Emissions Control Technology Association Study: A Navigant Economics study commissioned 

by the Emissions Control Technology Association (ECTA) in June 2012 found that the cost to 

oil refineries to produce 10 ppm sulfur gas would equate to approximately one cent per gallon 

(108). Furthermore, the study found that these small costs would likely not be passed on to 

consumers through higher retail gasoline prices. 

Navigant also conducted a multiple regression analysis to test whether the increased cost to 

U.S. refiners of implementing the Tier 2 gasoline sulfur reductions from 300 ppm to 30 ppm 

were passed on to consumers in the form of higher retail gasoline prices. The analysis found 

that the increase in cost to U.S. refiners of about two cents per gallon were not passed on to 

consumers, suggesting that it is highly unlikely that the Tier 3 costs will be passed on to 

consumers. 

American Petroleum Institute Study: The American Petroleum Institute (API) commissioned a 

study by Baker & O’Brien (B&O) in 2011, which estimated that the sulfur reduction 

requirement of Tier 3 would increase the marginal cost of refining by 6 to 9 cents per gallon 

(109). The marginal costs reflect the cost to the refineries that would experience the highest 

costs, not the average costs as estimated by EPA. 

The API commissioned study also indicates that the fuel program would be economically 

beneficial to the refining industry. B&O do not anticipate any refinery shutdowns as a 

consequence of Tier 3 and the analysis indicates that all U.S. refineries would find it costeffective to make the investments necessary to comply with these standards and that the capital 

required to make the investments will be available. According to EPA, API’s analysis “would 

suggest that the oil industry would profit from 10 ppm low sulfur standard by roughly 4 to 7 

cents per gallon, or roughly $4 to $8 billion dollars per year as a result of gasoline sulfur 

control.” 

Opponents to Tier 2 claimed the cost to consumers would be 5 cents per gallon (117). 

However, the ECTA study and other sources have found that Tier 2 did not have any impact on 

retail gasoline prices (118). Additionally, EPA projected that the monetized health benefits of 

reductions of PM and ozone under the Tier 2 program would outweigh the costs by about 5:1 

(119). 

106 - Navigant Economics, Economic Analysis of the Implications of Implementing EPA’s Tier 3 

Rules, prepared for the Emissions Control Technology Association (June 14, 2012).

107 - MathPro, Inc., Refining Economics of A Natural Low Sulfur, Low RVP Gasoline Standard, 

prepared for The International Council on Clean Transportation (Oct. 25, 2011).
Tier 3 Summary and Analysis of Comments

7-13

108 - Navigant Economics, Economic Analysis of the Implications of Implementing EPA’s Tier 3 

Rules, prepared for the Emissions Control Technology Association (June 14, 2012).

109 - Baker & O’Brien, Incorporated, Potential Supply and Cost Impacts of Lower Sulfur, Lower RVP 

Gasoline, prepared for the American Petroleum Institute (July 2011).

117 - Environmental Protection Agency, Tier 2 Motor Vehicle Emission Standards and Gasoline Sulfur 

Control Requirements: Response to Comments, 23-20 (Dec. 1999).

118 - Navigant Economics, Economic Analysis of the Implications of Implementing EPA’s Tier 3 

Rules, prepared for the Emissions Control Technology Association (June 14, 2012).

119 - Environmental Protection Agency, Regulatory Announcement, EPA’s Program for Cleaner 

Vehicles and Cleaner Gasoline (Dec. 1999), available 

at http://www.epa.gov/tier2/documents/f99051.pdf.

Commenter: Environmental Defense Fund (EDF)

While the B&O study did not report an estimate of the average U.S. refiner cost of reducing the 

sulfur content to 10 ppm, EPA calculated it from the information B&O provided as 2.12 cents 

per gallon. The Navigant study compared the B&O average cost estimates with the MathPro 

estimates and concluded that the approximately one cent per gallon difference in the two 

estimates is due almost entirely to the difference between MathPro’s and B&O’s estimates of 

the U.S. refiners’ compliance-related investment costs. 

Commenter: International Council on Clean Transportation (ICCT)

The cost of reducing gasoline sulfur from 30 ppm to 10 ppm is very modest. The ICCT 

contracted with MathPro in 2011 to evaluate the cost of reducing sulfur from 30 to 10 ppm. 

MathPro found that the cost would be 0.8 to 1.4 cents per gallon, and these results are likely to 

be conservative. 

Gasoline Sulfur Reduction Cost 

The cost of reducing gasoline sulfur from 30 ppm to 10 ppm is very modest. The ICCT 

contracted with MathPro in 2011 to evaluate the cost of reducing sulfur from 30 to 10 ppm. 

MathPro found that the cost would be 0.8 to 1.4 cents per gallon. The cost estimates include 

revamping the FCC naphtha hydrotreaters, historical rates of return on investment, supplying 

the additional hydrogen needed, replacing small losses in both gasoline volume and octane, and 

expanding sulfur recovery.

In fact, these cost estimates are likely overstated, as MathPro assumed that all existing FCC 

naphtha hydrotreating capacity would require revamping even though many hydrotreaters 

installed to meet the Tier 2 sulfur requirements are already capable of meeting the 10 ppm 

standard. 

A separate study carried out by Baker and O’Brien for the American Petroleum institute (API) 

estimated that production of 10 ppm sulfur gasoline would increase the marginal refining cost 

by 6–9 cents/gallon. However, there are two main reasons why these marginal cost estimates in 

the API study are unrealistic and should not be used. 
Chapter 7: Costs

7-14

First, in the Baker and O’Brien methodology, the indicated marginal cost is the highest cost of 

sulfur control that would be incurred by the least efficient refinery or refineries in the US. The 

petroleum market in the US is regional, i.e., there is not a single market. It is possible that the 

least efficient and highest cost refinery may be in, for example, PADD 4 and have a particular 

market to itself. That refinery might be able to pass the marginal costs on to producers in that 

market but will not have any effects in the rest of the US. However, this is not the typical case,

as most refineries are not so isolated. High cost refineries that are not isolated will not be able 

to pass the marginal costs onto consumers, due to competition from other efficient refineries. 

As a result, it is the average costs, not the marginal costs that represent the actual increase in 

the refining cost. 

If the average refining costs are considered instead of marginal costs and Baker and O’Brien’s 

investment costs for FCC naphtha hydrotreating are properly adjusted, Baker and O-Brien’s 

estimated refining costs would be similar to those estimated by MathPro. 

Commenter: Manufacturers of Emission Controls Association (MECA)

MECA agrees with EPA’s assessment that the cost of lowering average gasoline sulfur levels 

from today’s 30 ppm national average to the proposed 10 ppm national average is on the order 

of one penny per gallon of fuel. EPA’s gasoline cost assessment is supported by gasoline cost 

studies commissioned by the National Association of Clean Air Agencies (NACAA) and the 

Emission Control Technology Association (ECTA) that also indicate that costs for reducing 

gasoline sulfur levels to a 10 ppm national average are approximately one penny per gallon. 

Commenter: MathPro

In the summer of 2011, the International Council on Clean Transportation commissioned us to 

estimate the U.S. refining sector’s investment requirements and average cost for reducing 

average sulfur content of the U.S. gasoline pool from 30 ppm, the current standard, to 10 ppm, 

the proposed Tier 3 standard, and also for reducing the summer re-vapor pressure standard of 

U.S. conventional gasoline. Our report from that study was submitted to EPA in October of 

2011. 

My testimony today deals exclusively with sulfur control.

And that corresponds to an average cost of eight-tenths of a percent to 1.4 cent per gallon of 

gasoline.

This range of estimated average cost reflects different assumptions regarding two economic 

factors: the rate of return on refinery investment and the capital cost of revamping FCC naphtha 

hydro treaters, a particular type of unit in U.S. refineries to enable those units to carry out the 

more severe de-sulfurization needed to meet the 10 ppm standard.

The higher estimate of 1.4 cents a gallon reflects a 10 percent after tax return on investment and 

a capital cost for revamping of about 50 percent, about half, of the capital costs for a grass roots 

unit of the same kind and size. The lower estimate of eight-tenths of a cent a gallon reflects a 
Tier 3 Summary and Analysis of Comments

7-15

seven percent pre-tax return on investment, and about a 30 percent factor applied to the capital 

cost of revamping a grass roots unit.

Commenter: Medical Advocates for Healthy Air

By opponents of the Tier 3 standard, gasoline prices will increase by $.06 to $.09 per gallon. 

The EPA’s estimate is a mere $.01 per gallon. It is important to remember that when the EPA 

introduced Tier 2 standards to reduce the sulfur content of gasoline from 300 to 30 ppm, the 

increased cost of gasoline was much lower than the EPA’s estimate of $.02 cents per gallon. 

There is no reason to believe that the EPA’s estimate this time is conservative, and the ultimate 

cost may turn out to be less than 1 cent per gallon. 

Commenter: National Association of Clean Air Agencies (NACAA)

While the emission benefits of Tier 3 are very high, the costs of the program are very low. In 

our 2011 study, NACAA predicted an increase in the cost of gasoline of less than a penny a 

gallon and EPA has found the same (EPA’s analysis estimated 0.89 cents per gallon). 

Commenter: Natural Resources Defense Council (NRDC)

NRDC supports the EPA’s assessment that the average costs to reduce gasoline sulfur to 10 

parts per million is less than one cent per gallon. Recent estimates by the American Petroleum 

Institute (API) of 6 to 9 cents per gallon are not justified as average compliance costs. Further, 

the API estimates include per-gallon profits of 4 to 7 cents per gallon, which translates into $4 

to $8 billion in windfall profits for the oil industry each year. 

NRDC supports the EPA’s assessment that the average costs to reduce gasoline sulfur to 10 

parts per million is less than one cent per gallon. Recent estimates of 6 to 9 cents per gallon by 

the American Petroleum Institute (API), an association of oil companies, are not justified as 

average compliance costs and are inconsistent with figures by API’s own members, which 

estimate costs as either immaterial to their business or less than a penny a gallon. 

The 1.23 cents/gallon difference between the 2.12 cents/gallon average cost and EPA’s 0.9 

cents/gallon estimate can be explained by two factors. First, the API commissioned study 

assumes an additional 10 percent rate of return on investment (ROI) but ignores refiners’ ability 

to depreciate their investments so implicitly assumes a higher ROI than normal. In contrast, 

EPA assumes that the industry requires a 10 percent ROI after tax deductions are considered 

which is equivalent to a before tax ROI of 7 percent. EPA finds that when the API estimate is 

adjusted to a 7 percent before tax ROI, the API cost would be 1.58 cents per gallon.

Second, the remaining 0.69 cents/gallon difference can be attributed to differences in annual 

costs to install and operate the desulfurization equipment. The API commissioned study 

estimated a total annual cost of $2.4 billion compared to the EPA estimate of about $1.3 billion 

due to differences in equipment costs. As EPA notes in the DRIA, API’s claimed cost for a key 

piece of equipment to desulfurize oil, the fluidized catalytic cracker postreater, is 350 percent 

higher than EPA’s estimate.
Chapter 7: Costs

7-16

EPA has assessed the pre-regulation cost estimates by API to comply for clean fuel regulations 

with the actual impact seen in the marketplace. As shown in the figure below [Figure 1 can be 

found on p. 10 of Docket number EPA-HQ-OAR-2011-0135-4286-A1] from EPA’s peerreviewed report “Comparison of EPA and Other Estimates of Mobile Source Rule Costs to 

Actual Price Changes” (21) API’s estimates for regulations adopted in the 1990s have been 3.6 

to 6.4 times higher than actual observed price changes.

While the EPA report did not include the actual cost of the most recent gasoline sulfur 

reductions, a recent study by Navigant Economics (22) found that Tier 2 gasoline sulfur 

regulations, which API estimated would cost about 3 cents per gallon, (23) have had no 

discernible impact on retail prices.

Still, however, the oil industry claims that the Tier 3 sulfur reductions are too expensive. It 

appears that the industry believes that the public health protection should only be pursued if 

they can generate huge profit margins for the industry. API recently estimated the cost of 

complying with Tier 3 sulfur requirements at six to nine cents per gallon. EPA estimates the 

average cost at less than a penny, or .9 cents per gallon using the API assumptions. Most of the 

difference between the API and the EPA estimates is API’s projected profit margin.

As EPA described in the draft regulatory impact analysis, API’s cost estimate assumes a profit 

of four to seven cents per gallon, which translates into $4 to $8 billion in windfall profits for 

the oil industry each year. NRDC estimates that the oil industry is projecting an astounding 

rate of return on investment of 180 to 340 percent.

18 - EPA, “Draft Regulatory Impact Analysis: Tier 3 Motor Vehicle Emission and Fuel Standards”, 

EPA-420-D-13-002, March 2013.

19 - David C. Tamm and Kevin P. Milburn (Baker and O’Brien Incorporated), “Addendum to Potential 

Supply and Cost Impacts of Lower Sulfur, Lower RVP Gasoline,” March 2012.

20 - EPA, op. cit. Figure 5-1.

21 - Anderson, John F. and Sherwood, Todd, “Comparison of EPA and Other Estimates of Mobile 

Source Rule Costs to Actual Price Changes”, SAE Technical Paper 2002-01-1980, May 2002.

22 - Schink, George R., Ph.D. and Hal J. Singer, Hal J., Ph.D., Navigant Economics, “Economic 

Analysis of the Implications of Implementing EPA’s Tier 3 Rules”, Prepared for the Emissions Control 

Technology Association, June 14, 2012.

23 - Anderson, op. cit.

Commenter: Pennsylvania Department of Environmental Protection (DEP)

DEP recognizes that the proposed rules may increase costs for some refineries located in this 

region, and raise the cost of gasoline. 

The EPA should reexamine the estimated increase in production and at-the-pump costs.

According to the results of a study performed by the energy consulting firm Baker and O’Brian, 

the American Petroleum Institute (API) estimates a cost increase to consumers of six to nine 

cents per gallon with the proposed Tier 3 low sulfur gasoline. The EPA estimates a cost 

increase of about one cent per gallon. EPA used the industry’s cost models to model costs, and 

had the cost results reviewed by industry consultants. The EPA offers several reasons as to why 
Tier 3 Summary and Analysis of Comments

7-17

the cost discrepancy exists, but never fully closes the gap in costs. Recently, refining 

companies, including the nation’s largest, Valero, have disputed the API cost estimate. These 

refiners have indicated that the capital costs associated with complying with the Tier 3 

standards will be lower than the $10 billion API estimate. EPA should consult directly with 

refining companies to close the gap between these cost estimates. 

Commenter: Petroleum Marketers Association of America (PMAA)

PMAA represents over 8000 independent petroleum marketing companies who market liquid 

fuels at both wholesale and retail. We have examined the two cost related reports prepared by 

Mathpro and Baker/O’Brien. We are concerned that the penny per gallon cost identified by 

Mathpro is not accurate and consumers will be burdened with unjustified and burdensome 

higher gasoline costs. 

If in fact EPA eventually concludes the cost burden will exceed a penny per gallon, we believe 

EPA should revise the final rule to keep the costs at that threshold. 

Commenter: Refinery Automation Institute, LLC

To get an idea of costs, using DOE EIA June 3, 2013 price differential between New York 

gasoline and Los Angeles CARB gasoline of 13 cents/gallon, we are talking about a countrywide price burden increase of approximately 8.7 million bpd X 42 gal/bbl X $0.13/gal=$47.5 

million/day, or an additional $17.3 billion a year that consumers have to pay. In the current 

economic environment with 23+ million unemployed, this seems to me unconscionable, even 

though 2017 seems far in the future. 

Commenter: Sierra Club

In addition, EPA provides sufficient support that the 10 ppm sulfur level is economically 

feasible, including a refinery-specific cost of compliance study. On average, a 10 ppm sulfur 

level would cost refineries $0.97/gallon without the ABT program, and the costs decline with 

the inclusion of ABT and intra-company credit transfers. EPA further justifies the 10 ppm as a 

practical level because costs of further desulfurization would be costly at the present time. 

While the American Petroleum Institute’s scare tactics claim that these standards would cause 

gas prices to skyrocket, independent studies have shown that these standards can be achieved 

for less than a penny a gallon. This is a clear case where we can clean our air, protect our 

public health, and create jobs by reducing pollution from our cars and trucks.

Commenter: Sierra Club, Clean Air Watch, Respiratory Health Association

While the American Petroleum Institute’s scare tactics claim that these standards would cause 

gas prices to skyrocket, independent studies have shown that these standards can be achieved 

for less than a penny a gallon. This is a clear case where we can clean our air, protect our public 

health and create jobs by reducing pollution from our cars and trucks. 
Chapter 7: Costs

7-18

Commenter: Private Citizen

If my math is correct, Americans consume around 64.3 billion gallons of gas annually. A one 

cent increase per gallon would equate to a cost of $64,300,000, plus applicable taxes. Over a 17 

year period (2013 - 2030) the cost to US car owners would be over $109 trillion, and that’s just 

at a cost of 1 penny more per gallon and excluding city, county, state and federal taxes.

Our Response:

We received comments in support of and against our costs assessments, which included 

average and marginal costs for the sulfur standards. Commenters that agreed with our costs 

assessments viewed them as reasonable in light of the benefits of the Tier 3 program. Several 

comments disagreed with the refinery industry’s costs assessments that characterized our costs 

assessments as underestimating the average and marginal costs of sulfur controls.

As explained in Chapter 5 of the Final Regulatory Impact Analysis, we made a number 

of changes to the cost model since our proposal. Some of these changes are in response to 

comments we received on the proposed rulemaking, others are in response to the first round of 

peer reviewer comments and others were due to our own initiative to further improve the 

refinery model. Because of the number and scope of changes to the cost model, we conducted 

a second round of three independent peer reviews. We then addressed or incorporated the 

comments of the second round of peer reviews as appropriate. We also reviewed how credits 

are traded under the Tier 2 sulfur control program and found that sulfur credits are frequently 

traded between refining companies. Discovering that sulfur credits are widely traded, we 

changed the basis for the cost analysis to assume nationwide credit trading. The refinery cost 

model estimates that Tier 3 will cause refiners to make about $2 billion in capital investments 

and the program will cost 0.65 cents per gallon when the program costs are averaged over the 

entire U.S. gasoline pool. We believe that these costs are reasonable for achieving much lower 

sulfur gasoline and are far outweighed by the benefits due to lower emissions of environmental 

pollutants. 

We also reviewed cost estimates derived by several commenters who conducted their 

own cost studies. The cost studies conducted to estimate sulfur control costs for Tier 3 gasoline 

sulfur control to a 10 ppm standard derived very similar costs. The principal differences in 

costs can be attributed in large part to the impact of the averaging banking and trading (ABT) 

program. In total, three cost studies were conducted which estimated the cost of a 10 ppm 

average sulfur standard. In addition to our cost study, the American Petroleum Institute (API) 

and the International Council for Clean Transportation (ICCT) conducted cost studies to 

estimate the cost of complying with the proposed 10 ppm average cost standard. The 

following table summarizes the cost estimates conducted by the various cost studies. 
Tier 3 Summary and Analysis of Comments

7-19

Summary of Average Per-Gallon Costs (7% before-tax ROI)

With Credit 

Trading

No Credit Trading

EPA EPA API ICCT

0.65 0.87 0.97 0.8

The above table shows that our estimated costs for a 10 ppm average gasoline sulfur 

standard which includes an ABT program is 0.65 cents per gallon. For the three cost studies 

which assessed the costs without allowing for credit generation and trading, estimate costs fall 

in the range of 0.8 to 1.0 cents per gallon.1

To derive the per-gallon costs by API shown above, we had to combine the results of 

two separate cost studies conducted by API. One API cost study conducted by Baker and 

O’Brien estimated the cost of a 10 ppm average sulfur standard with a 20 ppm cap standard, 

which is 1.58 cents per gallon (before-tax 7% ROI). The second API cost study conducted by 

Turner Mason and Co. estimated the cost of a 20 ppm cap standard relative to the current 80 

ppm cap sulfur standard. The 1.58 cents per-gallon cost estimated by Baker and O’Brien study, 

which is based on an estimated capital cost of 9.6 billion dollars, is offset by removing API’s 

estimated 6 billion capital cost for a 20 ppm cap standard, thus reducing API’s per-gallon cost 

estimate from 1.58 cents per gallon to 0.97 cents per gallon. While we used the two API cost 

studies to estimate a per-gallon cost without a 20 ppm cap standard, we in no way endorse these 

cost studies as both studies have overestimated the capital costs. The result is nevertheless 

instructional. The costs of all three organizations looking at the same standards, but without 

assuming the ability for refineries to generate and trade sulfur credits result in very similar 

costs. This serves to support EPA’s belief that had these studies also evaluated the impact of 

trading sulfur credits between refineries they would have also resulted in cost estimates similar 

to our 0.65 cent per gallon estimate. 

One of the commenters suggested that EPA should consult directly with refining 

companies to estimate the costs. We did so extensively during the development of the rule, 

meeting individually with companies that represented more than 60% of the refining capacity 

in the US. In these discussions the input we received ranged broadly from general support for 

our estimates to general support for API’s estimates or comparably high cost estimates. During 

the development of the rule we also consulted heavily with the contractors, technology firms, 

engineering firms, and vendors that service the refining industry, including submitting our 

modeling to two separate rounds of independent peer review by industry experts. This 

expertise was all utilized in our modeling and our assessments. The Natural Resources Defense 

Council (NRDC), in their comments on the proposal provided an overview of the public 

 

1

 As summarized and discussed below in Chapter 7.2.5 of this Summary and Analysis of Comments document, 

the oil industry states that the LP refinery modeling cost analysis conducted by Mathpro for ICCT reflect some 

averaging, like a credit trading program, which is inherent in LP refinery models. In its cost analysis for ICCT, 

Mathpro assumed that each refinery would either add a grassroots unit or revamp an existing FCCpostreater and 

chose a representative unit size for the refineries in each PADD that it modeled, Thus, we believe that Mathpro 

avoided most all the potential overoptimization, and related underestimation in costs, which can occur using such 

refinery models. 
Chapter 7: Costs

7-20

statements made by some of the publicly traded refiner (see Chapter 7.2.3 below). While this 

could not be used in our modeling or analysis, it may provide some general perspective on 

expected Tier 3 compliance costs. 

7.2.2.2. Marginal Cost

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

Economic theory and discussion of average vs. marginal costs: Throughout EPA’s analysis, and 

especially in Chapter 5.2 of the DRIA, EPA places extraordinary emphasis on their average 

cost calculations, which for reasons explained above, are biased downward. At the same time, 

EPA mistakenly ignores the marginal cost impacts. EPA implicitly acknowledges the relevance 

of marginal costs as evidenced by EPA’s analysis of cost impacts refinery-by-refinery that 

highlighted the marginal cost. 

Adjusting for shortcomings mentioned above in EPA’s modeling efforts, their results could 

align very well with the Baker & O’Brien study. The marginal cost graph below [See Figure 9 

on p. 31 of Docket number EPA-HQ-OAR-2011-0135-4276-A2] (from the Baker & June 28, 

2013 31 O’Brien report) illustrates the point that a larger volume of gasoline production will 

incur higher than average costs of production. By definition, half the volume falls on either side 

of the average. Figure 9 below includes a point estimate of approximately 1 cent per gallon 

(i.e., EPA and MathPro) and illustrates approximately 50% of gasoline production is covered 

by the average cost, the other half is not. Even EPA’s graphs demonstrate this fact. 

The Baker & O’Brien study concluded that allocating compliance and capital cost on an 

annualized basis resulted in a marginal cost of 6 to 9 cents per gallon in most markets. EPA’s 

own analysis in the DRIA (Figure 5-4) illustrates a marginal cost curve that appears to exceed 

6.5 cents per gallon. Does EPA believe that gasoline will be delivered to market at the average 

cost of production? 

EPA needs to recognize that basic economics teaches that the market will have to bear the 

marginal cost of bringing the last increment of demanded supply into the market. Thus the 

marginal cost represents the true cost of this proposal to the consumer. 

In section 9.3 of the DRIA, EPA reports that they do not estimate consumer price impacts of 

the proposed Tier 3 program. However, EPA goes on to note that the increase “should be 

positive and up to the increase of manufacturers’ cost of gasoline production.” 

In this contradiction, not only does EPA point out their analytical shortcomings, but EPA has 

also ignored economic theory. Increasing marginal costs of production, (illustrated in both 

Baker & O’Brien and EPA) results in a positive relationship between total quantities supplied 

and price of that quantity in the market place (i.e. supply curve). 
Tier 3 Summary and Analysis of Comments

7-21

EPA focuses on the average cost, which is misleading because refineries producing up to 1⁄2 of 

gasoline production will by definition incur costs higher than average, some significantly 

higher, in order to comply with the Tier 3 proposed regulation. In order to ensure these 

marginal supplies of gasoline are brought to the market place, market signals will be required to 

incentivize these incremental supplies. 

Gasoline costs. Navigant’s portrayal of market mechanisms is misleading - the fact is that 

consumers ultimately bear the cost of regulations. This has been true with numerous 

regulations, including Tier 2, and will likely be repeated with Tier 3 costs. Navigant’s use of 

European Brent spot prices as an example to compare against U.S. gasoline retail prices makes 

little sense, since the Brent price has been very unrepresentative of actual average U.S. crude

costs for the past 5 years. 

15 - MathPro Inc. Refining Economics of a National Low Sulfur, Low RVP Gasoline Standard. 

Performed for The International Council For Clean Transportation. October 2011. 

EPA’s modeling shortcomings: It is interesting how EPA spends a large portion of Chapter 5 of 

the DRIA discussing their refinery by refinery model. However, EPA fails to mention their 

refinery by refinery results of 4.5 cents per gallon marginal costs even with an Averaging, 

Banking, and Trading (ABT) program in place. Given the shortcomings mentioned above of 

EPA modeling efforts, this result if adjusted properly would align very well with the Baker & 

O’Brien results which did not include an ABT program. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

EPA’s calculation errors: The costs that EPA reports on Figure 5-6 [of the DRIA] and in the 

proposal text are a nationwide average cost of 0.79 cents per gallon. However, if one simply 

uses the data on the graph, it appears that the average cost is 1.08 cents per gallon. If one takes 

the same steps with Figure 5-1, which is very similar to the Figure VII-2 used in the proposal, 

the average cost calculates to be 1.21 cents per gallon instead of the 0.97 cents per gallon that 

EPA uses in the text of the proposal. One would suspect that these differences are due to 

volume weighting but for EPA to simply slap an average cost on a graph which does not 

demonstrate that average is very misleading and confusing. At the very least, EPA should add 

an explanatory footnote. 

Commenter: Marathon Petroleum Company LP (MPC)

EPA makes the assumption that mandated 10 ppm average sulfur level will result in refineries 

targeting exactly 10 ppm. Refinery operations do not always run exactly as planned and as a 

result refiners must aim below the 10 ppm target, since ending the year above 10 ppm is 

unacceptable. Refineries will aim for somewhere around 8 ppm, so that an upset at the end of 

the year does not result in non-compliance for the entire year. Even with Averaging, Banking 

and Trading (ABT) program, the refineries generating credits and those using the credits will 

target around 2 ppm below the average that they must have for compliance. The ability to 

create Tier 2 sulfur credits is in part caused by this under targeting of sulfur levels. EPA 

assumes that refineries operate with perfection and in that world everyone will on average 
Chapter 7: Costs

7-22

achieve exactly 10 ppm sulfur in gasoline. The fact is that the refining industry has almost 

always overachieved when meeting mandated product specifications. EPA needs to redo their 

analysis based on an 8 ppm sulfur average. 

EPA’s modeling shortcomings: It is interesting how EPA spends a large portion of Chapter 5 of 

the DRIA discussing their refinery by refinery model. However, EPA fails to mention their 

refinery by refinery results of 4.5 cents per gallon marginal costs even with an Averaging, 

Banking, and Trading (ABT) program in place. Given the shortcomings mentioned above of 

EPA modeling efforts, this result if adjusted properly would align very well with the Baker & 

O’Brien results which did not include an ABT program. 

Economic theory and discussion of average vs. marginal costs: Throughout EPA’s analysis, and 

especially in section 5.2 of the DRIA, EPA places extraordinary emphasis on their average cost 

calculations, which for reasons explained above, are biased downward. At the same time, EPA 

mistakenly ignores the marginal cost impacts. EPA implicitly acknowledges the relevance of 

marginal costs as evidenced by EPA’s analysis of cost impacts refinery-by-refinery that 

highlighted the marginal cost. 

Adjusting for shortcomings mentioned above in EPA’s modeling efforts, their results could 

align very well with the Baker & O’Brien study. The marginal cost graph below (from the 

Baker & O’Brien report) illustrates the point that a larger volume of gasoline production will 

incur higher than average costs of production. By definition, half the volume falls on either side 

of the average. Figure 7 includes a point estimate of approximately 1 cent per gallon (i.e. EPA 

and MathPro) and illustrates approximately 50% of gasoline production is covered by the 

average cost, the other half is not. Even EPA’s graphs demonstrate this fact. 

The Baker & O’Brien study concluded that allocating compliance and capital cost on an 

annualized basis resulted in a marginal cost of 6 to 9 cents per gallon in most markets. EPA’s 

own analysis in the DRIA (Figure 5-4) illustrates a marginal cost curve that appears to exceed 

6.5 cents per gallon. Does EPA believe that gasoline will be delivered to market at the average 

cost of production? 

EPA needs to recognize that basic economics teaches that the market will have to bear the 

marginal cost of bringing the last increment of demanded supply into the market. Thus the 

marginal cost represents the true cost of this proposal to the consumer. 

In section 9.3 of the DRIA, EPA reports that they do not estimate consumer price impacts of 

the proposed Tier 3 program. However, EPA goes on to note that the increase “should be 

positive and up to the increase of manufacturers’ cost of gasoline production.” 

In this contradiction, not only does EPA point out their analytical shortcomings, but EPA has 

also ignored economic theory. Increasing marginal costs of production, (illustrated in both 

Baker & O’Brien and EPA) results in a positive relationship between total quantities supplied 

and price of that quantity in the market place (i.e. supply curve). 
Tier 3 Summary and Analysis of Comments

7-23

EPA focuses on the average cost, which is misleading because refineries producing up to 1⁄2 of 

gasoline production will by definition incur costs higher than average, some significantly 

higher, in order to comply with the Tier 3 proposed regulation. In order to ensure these 

marginal supplies of gasoline are brought to the market place, market signals will be required to 

incentivize these incremental supplies. 

Gasoline costs: To believe Navigant, refiners did not pass any Tier 2 costs, average or 

marginal, to the consumer and are therefore highly unlikely to pass the Tier 3 costs on to the 

consumer. One has to wonder what kind of economist would truly believe that businesses don’t 

attempt to pass their costs on to consumers. If businesses can’t pass any of their costs on to the 

consumer; how do they stay in business? Playing sleight of hand with multiple regression 

analysis does not change the economic tenant that businesses must recover their costs to stay in 

business. Using a European Brent spot price to compare against U.S. gasoline retail prices 

makes little sense, since the Brent price has been very unrepresentative of actual average U.S. 

crude costs for the past 5 years. 

Commenter: United States Congress, House of Representatives, Pennsylvania, 7th District

Some estimates show that the proposed new rules will cost the American motorist an additional 

6 to 9 cents per gallon. Additionally, the EPA should consider the example of California, where 

it already has imposed regulations similar to Tier 111 and its motorists pay 40 cents more per 

gallon than the national average. 

Commenter: MathPro

Another difference is that our focus was on estimating average refining costs. This is 

sometimes called a social cost or a national cost. And we did not -- well, we did not return or 

publish a marginal cost, whereas the headline number in the Baker and O’Brien study was a 

marginal cost, you know, the economics of a high cost refiner. And we did not do that because 

we didn’t think it was appropriate for this analysis.

Commenter: Emissions Control Technology Association (ECTA)

It should be noted that Baker and O’Brien’s estimate implies that Tier 3 will generate profit for 

the refining industry. Baker & O’Brien estimated that the marginal cost of compliance—that is, 

the cost of compliance to the refinery that would incur the highest costs—would be 6 to 9 cents 

per gallon. Baker & O’Brien also assumed (without justification) that the highest cost refineries 

would set the price of gasoline. The difference between the average cost and marginal cost is 

the oil industry’s profit. Thus, Baker & O’Brien’s analysis suggests that the oil industry will 

profit from 10 ppm low sulfur standard by roughly 4 to 7 cents per gallon. If this were the case, 

then the oil industry would support Tier 3. 

20 - EPA Proposal, Fed. Reg. at 29977.

24 - Id. at 29977.

25 - Id. at 29978.
Chapter 7: Costs

7-24

26 - See, e.g., EPA, Regulatory Impact Analysis: Heavy Duty Engine and Vehicle Standards and 

Highway Diesel Fuel Sulfur Control Requirements, EPA420-R-00-026, Dec. 2000.

27 - Mathpro, Refining Economics of National Low Sulfur, Low RVP Gasoline, Oct. 2011, at p. 13 

(hereinafter Mathpro Study).

Commenter: Natural Resources Defense Council (NRDC)

The main difference between the API 6 to 9 cents/gallon estimates and EPA’s 0.9 cents/gallon 

estimate is expected profit for the oil industry. As EPA describes in the DRIA, API’s cost 

estimate assumes a profit of 4 to 7 cents per gallon, which translates into $4 to $8 billion in 

windfall profits for the oil industry each year (18). 

The API estimates are based on a study by consulting firm Baker and O’Brien (19) that finds 6-

9 cents per gallon is the marginal cost of upgrades to refineries that need the highest cost 

upgrades. The study assumes that the market price for gasoline would be set by the small 

number of high upgrade-cost refineries. A more appropriate measure of gasoline price impact is 

the average industry cost of compliance because the market prices will be set by the majority of 

gasoline volume that is produced by refineries that do not need to make expensive upgrades. 

Based on EPA’s assessment of refinery-by-refinery costs without a sulfur credit averaging, 

banking and trading (ABT) program, fewer than 10 refineries of the 111 U.S. refineries would 

incur costs above 3 cents per gallon and average refinery costs would be about 0.97 

cents/gallon (20). With the proposed ABT program, the average cost is further lowered to 0.89 

(or 0.9) cents/gallon. 

Using data from the Baker and O’Brien study, EPA was able to assess average industry 

compliance costs for 10 ppm gasoline. Sensitivity Case 4 from the Baker and O’Brien study 

shows annual costs of $2.39 billion with an expected gasoline production of 7,343 thousand 

barrels per day, not including California refineries that already produce an average of 10 ppm 

gasoline. These industry assumptions result in an average cost of 2.12 cents/gallon. Compared 

to the average cost of 2.12 cents/gallon, API’s gasoline price impacts of 6 to 9 cents/per gallon 

would result in windfall profits of 3.88 to 6.88 cents/gallon, or $4.3 billion to $7.7 billion in 

annual profits at their projected production rates. With these windfall profits, the oil industry is 

projecting an astounding rate of return on investments of 180 to over 330 percent. 

Our Response:

We received comments in support of and against our costs assessments, which included 

average and marginal costs for the sulfur standards. Commenters that agreed with our costs 

assessments viewed them as reasonable in light of the benefits of the Tier 3 program. Several 

comments disagreed with the refinery industry’s costs assessments that characterized our costs 

assessments as underestimating the average and marginal costs of sulfur controls.

API reports a cost estimate of 6 – 9 cents per gallon based on the refineries with the 

highest Tier 3 gasoline sulfur compliance costs in its cost analysis. API and commenters citing 

their study are trying to make the case that the refineries with the highest Tier 3 gasoline sulfur 
Tier 3 Summary and Analysis of Comments

7-25

compliance costs will translate into the price increase for gasoline at retail and that this 

represents the true cost of the Tier 3 sulfur control program. This argument fails on both 

counts.

First, while economic theory would support that the marginal cost supplier of gasoline 

may in fact set the price of gasoline in its various submarkets, there are far more and larger 

factors that impact the marginal cost supplier of gasoline than the cost of gasoline sulfur 

control. These include crude oil costs, refining costs, refinery complexity, operating costs, 

distribution costs and on and on. There is no evidence to suggest, and no evidence provided by 

the commenters, that refineries with the highest marginal costs for Tier 3 gasoline 

desulfurization bear any relationship to the marginal cost suppliers of gasoline in a market. A 

simple example highlights this. According to the Pace refining margin report for the fourth 

quarter of 2013, the US refineries with the poorest margins are those refineries refining a light 

sweet crude oil (Bonny Light). Also, the refinery likely setting the marginal price is probably a 

non-conversion refinery (does not have an FCC unit) because the refinery is not realizing the 

cost benefit of upgrading the poorest quality, lowest value part of the crude oil barrel. 

However, because this refinery does not have an FCC unit, its gasoline sulfur level is likely 

already at 10 ppm or below, and thus, it would not be incurring any cost under Tier 3 (and it 

could actually earn credits if its gasoline sulfur is less than 10 ppm). The price setter refinery 

in this case will not incur a gasoline production cost increase under Tier 3, which could result 

in no impact on gasoline prices in the gasoline submarket. 

’Second, even if the refineries with the highest marginal cost of gasoline production and 

the highest marginal Tier 3 gasoline desulfurization costs in each submarket were one and the 

same refineries, it may help inform potential market price impacts resulting from Tier 3, but it 

would not be appropriate to use this in assessing the cost of the Tier 3 program. The Office of 

Management and Budget (OMB) lays out the methodology to be used for estimating the costs 

and benefits of new regulatory programs.2 OMB states that the estimated costs not include any 

transfer payments. API’s cost analysis (not adjusting for the 20 ppm cap standard that the API 

cost analysis assumed) estimates that the social cost of the Tier 3 sulfur control program is 1.58 

c/gal (7% before-tax ROI), however the reported marginal costs is 6 – 9 cents per gallon. Thus, 

the amount of the transfer payment is 4.42 – 7.42 cents per gallon, which corresponds to 4 to 8 

billion dollars per year. Thus, the marginal cost estimated by the API cost assessment would 

overestimate the social cost by a factor of 300 to 500 percent. It assumes that consumers would 

pay this additional cost, resulting in the oil industry realizing a substantial profit from Tier 3. 

Furthermore, the marginal cost estimates assumed by the commenters are inflated. As 

discussed in Section VII.B of the preamble to the final rule and in Chapter 5 of the RIA, the 

cost analysis conducted by Baker and O’Brien modeled a more stringent sulfur control program 

than the one finalized by EPA. The Baker and O’Brien cost analysis assumed a 20 ppm cap, 

which precluded refineries from utilizing the trading flexibility inherent in the Tier 3 program. 

This caused every refinery to have to invest capital to comply rather than allowing them the 

flexibility to comply through the use of credits. This in turn drove up the marginal costs. In 

 

2

 Economic Analysis of Federal Regulations under Executive Order 12866, Office of Management and Budget, 

January 11, 1996.
Chapter 7: Costs

7-26

addition, as discussed in Chapter 7.2.3 below, the Baker and O’Brien study assumed capital 

costs well above what is reasonable, further driving up the marginal cost estimates. In contrast 

to the Baker and O’Brien marginal cost range of 6-9 cents per gallon, our final rule estimates 

marginal costs only as high as 2.8 cents per gallon, and that is only for a single refinery that 

very well may have other compliance options available to it that we were unable to model. The 

next several highest marginal cost refineries are in the 1.5-2.1 cent per gallon range, and only 

15 refineries are projected to have costs higher than 1 cent per gallon.

What Commenters said:

Commenter: Marathon Petroleum Company LP (MPC)

EPA’s calculation errors:

The costs that EPA reports on Figure 5-6 and in the proposal text are a nationwide average cost 

of 0.79 cents per gallon. However, if one simply uses the data on the graph, it appears that the 

average cost is 1.08 cents per gallon. If one takes the same steps with Figure 5-1, which is very 

similar to the Figure VII-2 used in the proposal, the average cost calculates to be 1.21 cents per 

gallon instead of the 0.97 cents per gallon that EPA uses in the text of the proposal. One would 

suspect that these differences are due to volume weighting but for EPA to simply slap an 

average cost on a graph which does not demonstrate that average is very misleading and 

confusing. At the very least, if EPA has adequate justification for this average cost, it must add 

a detailed explanatory footnote. 

Our Response:

We changed the format of these figures in our final rule document to indicate the full 

range of costs across all the refineries. The relationship between the average costs and the 

range of refinery-specific costs is clearer to the reader.

7.2.3. Capital Cost

What Commenters Said:

Commenter: American Fuel & Petrochemical Manufacturers (AFPM)

A Baker and O’Brien analysis estimates that a gasoline sulfur content reduction will cost 

refiners $10 billion in capital costs, and $2.4 billion per year in operating costs, increasing the 

cost of producing gasoline by six to nine cents per gallon. [This comment can also be found in 

section 7.2.2 of this comment summary.]

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

EPA has chosen to underestimate the costs of a proposed program in an effort to improve the 

appearance of their cost/benefit analysis. EPA significantly underestimated refinery capital 
Tier 3 Summary and Analysis of Comments

7-27

costs, e.g., FCC post-treater 1,500 $/B vs. 6,800 $/B in Baker & O’Brien. Even though EPA 

criticized the Baker & O’Brien capital costs, they admitted that EPA received two vendor 

estimates for grassroots FCCU post-treating and elected to ignore the higher cost estimate. 

Significant differences between preliminary vendor estimates and actual refinery project costs 

EPA presumes a high degree of accuracy from vendor estimates and makes no adjustments to 

reflect that vendors are typically incentivized to provide the lowest possible estimates. After 

more thorough negotiations between refiners and vendors, engineering complexities are 

addressed and costs for specific technologies at specific refineries typically increase. Expertise 

in capital improvements at refineries is necessary to evaluate vendor estimates; EPA is not 

appropriately challenging estimates to the point that they provide realistic cost estimates or 

design factors. 

Refiners and refinery construction contractors typically have an idea of the variability in capital 

costs estimates, and they typically adjust vendor estimates accordingly based on their past 

experiences with particular vendors. EPA lacks this expert knowledge and thus makes a low 

estimate of capital costs. In addition, adapting theoretical design to a real refinery platform 

always results in extra costs to handle these interface adjustments. Refiners and refinery 

construction contractors typically add some percentage above the estimate to cover these 

contingencies, but EPA has not factored in these costs. 

Critique of Navigant study (16) – The Navigant study makes incorrect claims on: 

Refinery capital costs. Navigant starts their analysis with the assumption that MathPro and EPA 

are the “experts” in the area of sulfur reduction costs. In this particular case this is not an 

accurate assessment; as both MathPro and EPA simply relied on rough vendor cost estimates. 

On the contrary, as mentioned earlier, the Baker & O’Brien study was based on discussions 

with many refiners to determine actual on the ground costs at refineries. In reality refineries 

cannot add on small increments of new units and the supporting utilities as the MathPro and 

EPA approach would suggest. As a result real world compliance costs are higher than rough 

estimates using a notional or theoretical refinery. 

16 - Schink, G. and Singer, H. (2012). Economic Analysis of the Implications of Implementing EPA’s 

Tier 3 Rules 

Commenter: Emissions Control Technology Association (ECTA)

Second, Baker and O’Brien’s capital cost assumptions are inflated compared to those used by 

EPA. In particular, the grassroots FCC postreater costs used by Baker & O’Brien are much 

higher than what EPA used (28). EPA’s capital costs are consistent with those estimated by 

both the National Petroleum Council and Jacobs. Baker & O’Brien based their capital cost 

estimates on the actual installation for the Tier 2 program. Because a grassroots FCC postreater 

installed for Tier 2 would typically remove ten times more sulfur than one installed for Tier 3, a 

grassroots FCC postreater installed for Tier 3 would be significantly less capital-intensive than 

a comparable Tier 2 FCC postreater. Yet Baker & O’Brien ignored this consideration entirely 

when relying on the Tier 2 benchmark. Moreover, interviews of experts at companies who sell 

and install desulfurization equipment to refiners also suggest that Baker & O’Brien’s capital 

cost estimates are not aligned with industry norms. For example, Baker & O’Brien’s cost 
Chapter 7: Costs

7-28

assumption for naptha desulfurization is 257 percent higher than the experts’ estimates. 

Correcting Baker & O’Brien’s capital cost estimates (along with its ROI assumption) brings its 

average compliance cost estimates into alignment with those of EPA (29). 

28 - EPA Proposal, Fed. Reg. at 29978.

29 - Id.

Commenter: Environmental Defense Fund (EDF)

Navigant interviews with companies engaged in implementing the refinery upgrades required 

to reduce the sulfur content of gasoline confirm that the MathPro estimates are in the 

reasonable range and that the Baker & O’Brien estimates are too high. The B&O study also 

does not take into account the well-established flexibility provided in the program through 

averaging and trading. 

In fact, several individual refiners have countered API’s claims about Tier 3. For example, the 

Northern Tier Energy LP, a refining and retail gasoline company, states that “preliminary 

engineering assessments predict that no capital spending will be required to comply with the 

new standards’ (111). CVR Refining, LP announced that “estimated costs to meet Tier 3 

standards are less than $20 million’ (112). Alon US Partners estimated Tier 3 will cost less than 

$30 million (113) and Calumet Specialty Products Partners also made a public statement that 

Tier 3 will not materially impact their business (114).

111 - Northern Tier Energy, Northern Tier Energy LP comments on EPA’s proposed Tier III standards 

(2013) [Press release], retrieved from http://finance.yahoo.com/news/northern-tier-energy-lp-comments183900329.html.

112 - CVR Energy, CVR Energy subsidiary CVR refining reports minimal investment required to meet 

EPA proposed Tier III standards (2013) [Press release], retrieved from 

http://investors.cvrenergy.com/phoenix.zhtml?c=203637&p=irolnewsArticle&ID=1803055&highlight=.

113 - Alon USA Energy,. Alon USA Energy comments on EPA’s proposed Tier III standards (2013) 

[Press release], retrieved from http://www.reuters.com/article/2013/04/08/tx-alon-epa-upgradesidUSnPnDA90077+160+PRN20130408.

114 - Calumet Specialty Products Partners, Calumet Specialty Products Partners, L.P. comments on 

EPA’s proposed Tier III standards (2013) [Press release], retrieved from 

http://markets.on.nytimes.com/research/stocks/news/press release.asp?docTag=201304100830PR 

NEWS USPRX DE91948&feedID=600&press symbol=4043615.

Commenter: International Council on Clean Transportation (ICCT)

Second, the API marginal costs are upwardly biased. Baker and O’Brien overestimated the 

investment costs for FCC naphtha hydrotreating, as indicated by MathPro’s informal contacts

with companies involved in refinery upgrading. Their survey showed that investment costs 

used by MathPro are in a reasonable range. 

Commenter: Marathon Petroleum Company LP (MPC)
Tier 3 Summary and Analysis of Comments

7-29

The Agency has significantly underestimated the costs for the required gasoline sulfur 

reductions, overestimated the benefits and failed to take into consideration the accuracy of the 

ozone and PM measurements used in their justification for this rule. Compliance with this Tier 

3 proposal will cost the refining industry about $10 billion, which is approximately what 

compliance with the Tier 2 gasoline regulations cost the industry. 

DRIA Cost/Benefit Analysis – Underestimated Costs: Well in advance of the release of the 

EPA Tier 3 proposed rule, API published two studies conducted by Baker & O’Brien: a 2011 

study titled “Potential Supply and Cost Impacts of Lower Sulfur, Lower RVP Gasoline” and a 

2012 study “Addendum to Potential Supply and Cost Impacts of Lower Sulfur, Lower RVP 

Gasoline.” 

EPA has chosen to underestimate the costs of a proposed program in an effort to improve the 

appearance of their cost/benefit analysis. EPA significantly underestimated refinery capital 

costs, e.g., FCC post-treater 1,500 $/B vs. 6,800 $/B in Baker & O’Brien. 

Significant differences between preliminary vendor estimates and actual refinery project costs

EPA presumes a high degree of accuracy from vendor estimates and makes no adjustments to 

reflect that vendors are typically incentivized to provide the lowest possible estimates. After a 

more thorough negotiations between refiners and vendors will engineering complexities that 

additional costs for specific technologies at specific refineries become fully acknowledged. 

Expertise in capital improvements at refineries is necessary to evaluate vendor estimates, and 

EPA is not appropriately challenging estimates to the point that they provide realistic cost 

estimates or design factors. 

Refiners and refinery construction contractors typically have an idea of the variability in capital 

costs estimates, and they typically adjust vendor estimates accordingly based on their past 

experiences with particular vendors. EPA lacks this expert knowledge and thus makes a low 

estimate of capital costs. In addition, adapting theoretical design to a real refinery platform 

always results in extra costs to handle these interface adjustments. Refiners and refinery 

construction contractors typically add some percentage above the estimate to cover these 

contingencies, but EPA has not factored in these costs. 

Critique of Navigant analysis (6): The Navigant study makes incorrect claims on: Refinery 

capital costs. Navigant starts their analysis with the assumption that MathPro and EPA are the 

“experts” in the area of sulfur reduction costs. In this particular case this is not an accurate 

assessment; as both MathPro and EPA simply relied on rough vendor cost estimates. On the 

contrary, as mentioned earlier, the Baker & O’Brien study was based on discussions with many 

refiners to determine actual on the ground costs at refineries. In reality refineries cannot add on 

small increments of new units and the supporting utilities as the MathPro and EPA approach 

would suggest. As a result real world compliance costs are higher than rough estimates using a 

notional or theoretical refinery.

6. Schink, G. and Singer, H. (2012). Economic Analysis of the Implications of Implementing EPA’s 

Tier 3 Rules
Chapter 7: Costs

7-30

Commenter: MathPro

Our analysis indicated that the refinery investment for meeting the 10 ppm gasoline sulfur 

standard would be in the range of $3 to $4 billion per year, and that the corresponding total 

annual refining cost would be in the range of $.9 to $1.5 billion a year. 

In turn, we estimated that the capital cost of a grass roots FCC naphtha hydro treater would be 

about $1,800 per barrel per day, which is a standard unit of capital cost measurement and 

refining, and that includes both on-site and offsite investments. 

Meeting the 30 ppm standard, we posited that the method of choice for refiners would be to 

revamp their existing units rather than build grass units of another type. Refineries that now 

meet the 30 ppm standard with these units would add facilities, go through a revamp, and 

through that achieve the 10 ppm standard.

We understand that many of these units that are already in place already have the capability to 

meet a 10 ppm standard, but in our analysis, we assume that all units in the U.S. refining sector 

would require revamping. 

The U.S. refining industry has already installed about 75 of these advanced units in order to 

comply with Tier 2, and many similar units have been installed in other countries as well.

Hence, the range of capital costs and operating costs for these units is now reasonably well 

established.

EPA: Earlier today we heard some testimony about a study that was commissioned by the 

American Petroleum Institute. Are you familiar with that?

Mathpro: I am, Baker and O’Brien.

EPA: Would you care to comment on the primary differences that account for the cost range in 

your work versus the six to nine cents that was cited this morning?

Mathpro: Sure. There are several. One has to do with the estimated capital cost for building 

grass roots FCC post treaters and, hence, for revamping them. The estimate that we use, which 

I mentioned in my testimony, is about $1,800 of daily barrel. I believe the Baker and O’Brien 

study used a number that was about double that approximately. So that was one difference.

Commenter: National Association of Clean Air Agencies (NACAA)

In terms of impacts on refiners, EPA estimates that 111 refineries could potentially be affected 

by Tier 3. Of this total, 16 would need to install new equipment to comply with Tier 3. Of the 

remaining 95 refineries, 66 could meet the requirements by modifying their existing equipment 

and 29 already comply with Tier 3 or could do so by making operational changes. 

Commenter: Natural Resources Defense Council (NRDC)

API’s Estimates are Not Supported by Member Companies. Public statements by several 

refineries indicate that the expected cost of compliance with Tier 3 regulations will be lower 

than API’s 6 to 9 cents/gallon estimate, if material at all. Valero Energy, which is the largest 
Tier 3 Summary and Analysis of Comments

7-31

independent refiner in the U.S., recently told a group of financial analysts that its Tier 3 

compliance will cost $300 to $400 million (24). Using Valero’s high cost estimate of $400 

million, with a 7 percent pre-tax return on capital and a 5 year depreciation, NRDC estimate 

that Valero’s s marginal cost is approximately 0.6 cents per gallon, which is more than 10 times 

less than the API high estimate. For Valero, the 0.6 cents per gallon translates into annual costs 

of approximately $97 million or just 2 percent of the $4.45 billion in pre-tax earnings that the 

company made on refining in 2012.

- Northern Tier, which operates a refinery in Minnesota, stated in a press release that its 

“current assessment is that the proposed updated standard will not have a material financial 

impact to the Company. Preliminary engineering assessments predict that no capital spending 

will be required to comply with the new standards” (25).

- CVR Energy, operating refineries in both Oklahoma and Kansas, announced that “the 

proposed U.S. Environmental Protection Agency Tier III sulfur regulations will have no impact 

on the company’s previously announced full year 2013 distribution guidance... The full amount 

of this upgrade was reserved as cash on the company’s balance sheet at the close of its IPO on 

Jan. 23, 2013...Operating cost increases as a result of the higher desulfurization levels of 

gasoline are not expected to be material to the company’s performance” (26).

- Calumet Specialty Products Partners, L.P., which is based in Indiana and operates eleven 

facilities located in Louisiana, Wisconsin Montana, Pennsylvania, Texas and Missouri, 

announced that its “current assessment is that the proposed updated standards are not expected 

to have a material financial impact to Calumet. Calumet’s preliminary assessments of its 

operations indicate that capital spending requirements, if any, will be immaterial to comply 

with the proposed updated standards” (27).

- Alon USA Partners, which owns and operates a refinery in Texas, issued a press release 

stating that “[o]perating cost increases as a result of the higher desulfurization levels of 

gasoline are not expected to be material to the partnership’s performance” (28).

24 - Siders, Alison, “Valero: EPA Gasoline Plan Would Cost Hundreds of Millions of Dollars,” Wall 

Street Journal, April 2, 2013.

25 - http://www.reuters.com/article/2013/04/03/ct-northern-tier-epaidUSnPnNY88352+160+PRN20130403.

26 - http://www.prnewswire.com/news-releases/cvr-energy-subsidiary-cvr-refining-reports-minimalinvestment-required-to-meet-epa-proposed-tier-iii-standards-201264271.html.

27 - http://online.wsj.com/article/PR-CO-20130410-907218.html.

28 - http://www.alonpartners.com/phoenix.zhtml?c=251560&p=irolnewsArticle&ID=1803979&highlight.

Commenter: Phillips 66 Company

Project Costs in Excess of EPA Estimate: 

Given the significant project scopes required, we believe EPA has significantly underestimated 

the cost to comply with the 10ppm proposal. In an independent study commissioned by API, 

consultants Baker and O’Brien determined that the capital cost required by industry will be 

about $10 billion in contrast to EPA’s estimate of $2.1 billion. 
Chapter 7: Costs

7-32

Based on preliminary analysis of our potential refinery projects, Phillips 66 believes the 

investment costs required to comply with the proposed standard are well in excess of EPAs 

estimates. The high investment required for the rule continue to place competitive pressures on 

an already capital intensive industry. 

Commenter: Union of Concerned Scientists (UCS)

Meeting the 10 ppm standard is estimated to cost the refiners less than a penny per gallon. An 

independent study by Navigant Economics confirms EPA’s estimates, finding that the cost of 

complying with Tier 3 for U.S. refiners is “in the vicinity of 1 cent per gallon” (13). 

Additionally, Navigant states that “this expression of the compliance costs on a cents per gallon 

basis does not imply that these compliance costs will be passed through fully to consumers.” 

According to analysis by the Center for American Progress, the oil industry is one of the 

world’s most profitable industries. The five largest companies took home a combined $118 

billion in profits in 2012 alone (15). It’s time for the oil industry to stop blocking progress –

and given their record profits, less than a penny a gallon is a small price to pay to protect the air 

we breathe.

13 - Schink, George R. and Hal Singer. 2012. Economic Analysis of the Implications of Implementing 

EPA’s Tier 3 Rules. Online at 

http://naviganteconomics.com/docs/061212%20Economic%20Analysis%20of%20the%20Implications

%20of%20Tier %203%20Sulfur%20Reduction%20Final_embargoed%20copy.pdf, p.14, accessed on 

June 21, 2013.

15 - Center for American Progress. 2013. Speed Trap: Big Oil Profits from High Gasoline Prices. 

Online at http://www.americanprogress.org/issues/green/news/2013/02/06/51967/big-oil-profits-fromhigh-gasoline-prices/ accessed on June 28, 2013.

Commenter: United States Congress, House of Representatives, Pennsylvania, 7th District

Refiners, including in the 7th congressional district and the greater Philadelphia area, are 

currently meeting the Tier II vehicle standards that reduced sulfur in gasoline from 300 parts 

per million to 30 parts per million — a 90-percent reduction. 

American refiners have already spent billions of dollars to achieve a 90 percent reduction in 

sulfur levels since 2004, and Tier III will require refiners to spend an estimated $10 billion in 

new infrastructure and another $2.4 billion per year in operating costs. These Washington 

requirements will further jeopardize our refining industry and workers, and increase the cost of 

end product fuels for consumers. 

Commenter: Navigant Economic

First, there are serious flaws in the approach employed by Baker and O’Brien on behalf of the 

American Petroleum Institute to estimate the compliance cost to refineries. Second, I’ve 

examined EPA’s cost benefit analysis. It comports with economic logic and best practices, and 

it validates our conclusions. Third, we examined the effects of the Tier 2 sulfur rule on the 

price of gasoline and found little to no impact suggesting the Tier 3 effect will be negligible.
Tier 3 Summary and Analysis of Comments

7-33

So going to my first point on the flaws in the Baker and O’Brien approach, there are several, 

but today I just want to address three. Baker and O’Brien failed to account for averaging and 

trading of credits, which reduces the compliance costs to refineries. As EPA explained, 

refineries with pre and post treaters are able to achieve further sulfur reductions below the 10 

parts per million standard at a relatively low incremental cost, and sell credits to refineries who 

would otherwise be faced with grass roots investments.

Averaging and trading reduces EPA’s estimated compliance cost from .97 cents per gallon to 

.79 cents per gallon, a reduction of nearly 20 percent with averaging in trading. Between eight 

and 25 high-cost refineries out of 11 would prefer to consume credits than to upgrade their 

facilities. Baker and O’Brien’s mistaken assumption that those high-cost refineries reduce the 

sulfur content of their gasoline they produce to 10 parts per million severely inflates their 

compliance cost estimates.

Second, Baker and O’Brien assume without support that the refinery with the highest cost of 

compliance will set the price of gasoline. However, if this were true, then the profits of the 

refinery industry, defined as the difference between the marginal cost and the average cost per 

gallon, would be four to seven cents, at which point the refiners should endorse Tier 3. Given 

the refiners’ opposition, it seems that Baker and O’Brien’s logic is faulty.

Third, Baker and O’Brien’s estimated capital cost for a grass roots FCC post treater is not 

reasonable according to companies that construct or install desulfurization units. Indeed, Baker 

and O’Brien’s capital cost estimates are between two and four times higher than industry 

benchmarks. Baker and O’Brien states that their estimates were based on actual installation for 

the Tier 2 program, but as EPA explains, a grass roots FCC post treater installed for Tier 2 

would remove about 10 times more sulfur than one installed for Tier 3, and, thus, would have 

significantly higher capital costs. Correcting this one defect in the Baker and O’Brien study 

causes their cost estimates to come into alignment with those of MathPro and of EPA.

EPA: Thank you for the, I guess, the support for our cost analysis. But if you could just spend 

just a moment, because you were cut a little short. So what are the main differences between, 

you know, our one cent a gallon and the six to nine cent estimate from Baker and O’Brien?

Navagant: So I think the points that I rattled off were the main drivers. One is this conflation 

of the average and the marginal. I think that what – when you actually saw for the average of 

the Baker and O’Brien, you don’t get that big of a divergence. You get something like one 

versus two.

But even there, the difference can be entirely explained away with just one change, and that’s 

this capital cost component of these treaters. And the way that we tried to ascertain that it was 

exaggerated was by interviewing actual providers of these equipments, these types of 

equipment and founding out whether their costs were reasonable. And they told us they 

weren’t.

Our Response:
Chapter 7: Costs

7-34

We received many comments in support of and against our capital costs estimates. 

Commenters in support of our estimates viewed them as reasonable while other commenters 

from the oil industry argued that we had underestimated those costs. Specifically, API 

commented that EPA significantly underestimated Tier 3 refinery capital costs and compared 

the capital cost it used in its cost study for a grassroots postreater, which is $6800 per barrel per 

day, to EPA’s capital cost which is $1,500 per barrel per day. Several commenters viewed the 

oil industry’s cost as inflated.

’We disagree with the cost comparison made by API.

3

 The total capital cost that we 

used for a grassroots postreater for the NPRM is higher than what API reported in its 

comments. The $1,500 per barrel per day value solely represents the inside battery limits costs 

(the direct costs associated with the hydrotreater), but when the offsite factor (representing the 

indirect costs of the hydrotreater) our capital costs total $1875 per barrel per day. When a 

separate overdesign factor that we applied is included (which was not included in the cost table 

in Chapter 5 of our Regulatory Impact Analysis document which summarized our capital cost, 

but was described in our description of our refinery-by-refinery model), our capital costs for a 

grassroots postreater increases to $2,015 per barrel per day. 

Before discussing the methodology used in deriving two cost estimates and the final 

cost estimates, we will review the steps that EPA and API took to estimate the capital costs for 

installing a grassroots postreater.

EPA’s Postreater Capital Costs 

The cost estimates that we are making for refineries are made in two steps. The first 

step is to estimate the inside battery limits (ISBL) costs, which are the costs for the primary 

units (i.e., reactor, heater compressors) subunits (pumps, heat exchangers strippers) and the 

piping, electrical and control hardware. The vendors understand their technology very well and 

understand how to make such cost estimates because they know how their technologies are 

currently configured and are being operated in refineries today (are the hydrotreaters being 

operated severely or more mildly), and therefore understand how the grassroots and revamps 

would have to be configured to achieve the targeted lower sulfur standard. 

The second step is estimating other costs called outside battery limit (OSBL) costs 

which include piping the new unit to other units, control building for control equipment and the 

operations personal, cooling towers, electrical switchgear laboratory facilities, etc. Vendor 

companies are generally not very good at estimating offsite costs because it requires experience 

installing such units in refineries, and the vendor companies rarely do that sort of work. For 

estimating the offsite costs for Tier 3 desulfurizing units we spoke to two engineering 

 

3

 In Baker and O’Brien’s report for API, the capital cost that they used is $6540 per barrel per day ($228.8 MM 

for a 35,000 barrel per day unit). However, when API submitted its comments to EPA, it reported a capital cost of 

$6800 per barrel per day. We believe that API adjusted its capital cost to be on the same basis as our costs which 

is 30,000 barrels per day instead of 35,000 barrels per day and this is why they report the value of 6800 instead of 

6540.
Tier 3 Summary and Analysis of Comments

7-35

companies (Foster Wheeler and Bechtel) which installed desulfurization units for Tier 2. In 

both cases, the engineering companies estimated that the offsite costs would be about 35% of 

the onsite costs and we used that offsite cost factor for our cost estimate (our offsite factor is 

within the range of 30% to 50% estimated by one vendor). Thus, we believe we are making a 

very good estimate for the ISBL and OSBL capital investments expected to be made for Tier 3. 

This has been corroborated by two rounds of independent peer review by knowledgeable 

experts in refining. 

API’s (Baker & O’Brien) Postreater Capital Costs

API’s costs are based on Tier 2 compliance costs. API obtained either estimated 

installation costs or actual installation costs (API did not specify) for FCC postreaters for 

installation in 5 different refineries for complying with the Tier 2 30 ppm gasoline sulfur 

standard. The postreater capital cost information which reflected cost information from the 

years 2003 to 2005 was adjusted upward to reflect mid-year 2009 capital costs using the 

Nelson-Farrar index and normalized to reflect a 35 thousand barrel per day unit. This resulted 

in an average ISBL cost of $144.5 million for installing a Tier 2 compliant FCC postreater. 

After API discussed this capital cost estimate with several refiners who built several of the 

units in recent years, those refiners felt that the estimated capital costs that API had calculated 

were too low, and one refiner thought that the estimated capital costs should be doubled. Based 

on the opinion expressed by that one refiner, API doubled its estimated capital costs for a 35K 

bbl/day FCC postreater to $228.8 million. For estimating the capital cost for revamps of 

existing postreaters, API applied a generic 30% cost estimation factor as their means for 

estimating the revamp costs from the grassroots cost.

Discussion of EPA and API Estimated Postreater Capital Costs 

EPA and API used two totally different cost estimation methodologies for estimating 

the capital costs. We estimated the FCC postreater costs using a bottom-up approach, while 

API used a top-down approach. Either approach is viable, although we favor our method for 

several reasons. 

1) For complying with the Tier 2 gasoline sulfur standard, a typical refinery would have 

installed an FCC postreater to desulfurize the FCC naphtha from about 800 ppm down 

to about 75 ppm, a 725 ppm, or a 91 percent sulfur reduction. In the case of a 

grassroots postreater that would be installed for Tier 3, the postreater would treat FCC 

naphtha already low in sulfur due to the pretreater installed before the FCC unit (these 

refineries are currently complying with Tier 2 using an FCC pretreater). Thus, the new 

grassroots FCC postreater installed for Tier 3 would only have to reduce the FCC 

naphtha from 100 ppm to 25 ppm, a much smaller 75 ppm or 75 percent sulfur 

reduction. A grassroots FCC postreater installed for Tier 2 would typically remove 10 

times more sulfur than one installed for Tier 3. This is important because a significant 

portion of the FCC postreater capital cost is devoted to avoiding the recombination 

reactions which occur when hydrogen sulfide concentrations are high and react with the 

olefins contained in the FCC naphtha. Thus, a grassroots FCC postreater installed for 

Tier 3 would be expected to be significantly lower in capital cost compared to a Tier 2 
Chapter 7: Costs

7-36

FCC postreater. API’s costs are based solely on Tier 2 compliance costs, which is one 

reason why their costs are high (we believe about 30% higher).

2) Refiner project cost estimates for adding an FCC postreater for Tier 2 may have 

included additional costs for other subprojects that the refiner may have included with 

the Tier 2 project, even though they may be unrelated to the FCC postreater project or 

for reducing the sulfur level of gasoline. API would not be able to distinguish these 

other costs from the desulfurization costs and would have included their costs in their 

estimate for Tier 3.

3) In their project design cost estimates, engineering companies add on an additional 

contingency cost beyond the best estimate for completing the project. They do so to 

guarantee the project completion under budget. We asked an engineering company 

what a typical cost guarantee contingency factor would be for capital cost projects. The 

engineering company typically adds 15% above and beyond the estimated costs. 

4) Based on an anecdotal comment by a refiner, API doubled the capital costs that it uses 

for an FCC postreater over the refinery installations cost estimates for Tier 2 which 

were adjusted to current year dollars.

We believe that these various factors associated with API’s cost estimation 

methodology led to the overestimation of API’s cost estimate for an FCC postreater. We know 

that API’s cost estimate for an FCC postreater is high because their estimated capital costs for 

an FCC postreater are higher than that for an FCC pretreater sized the same, however, FCC 

pretreaters are a much higher pressure and are constructed of much more expensive metallurgy 

than FCC postreater units. 

API commented that vendors are incentivized to provide the lowest possible costs and 

EPA failed to adjust them higher to reflect realistic capital costs. We believe that vendors can 

underestimate the cost of its costs when the vendors anticipate that its costs will be published 

and compared to other vendor costs. In this case, we wanted to avoid placing the vendors in 

that position, so we promised the vendors that we would not publish individual vendor cost 

estimates, but aggregate them together. For this reason, we believe that the vendors provided 

their best estimates for the capital costs of their grassroots units and revamps. In fact, we see 

no basis for this assertion when we look across the range and variety of data and sources made 

available to us. Conversely, these comments ignore the very real bias of the refining industry 

estimates themselves in estimating the costs of EPA fuel standards, which has been 

demonstrated in cost studies in the past. The only vendor that appeared to demonstrate a clear 

bias was the vendor that is also a refiner, and provided costs far out of line with other sources 

of information. This information proved unusable since it assumed Tier 2 was not in place, and 

not a valid estimate for the increment of sulfur control needed for Tier 3. We also believe that 

we are not overestimating capital costs based on the pitfalls inherent in the API capital cost 

estimation methodology. 

While we have high confidence in our estimated costs, the peer review comments make 

a strong case for accounting for additional costs. Three peer reviewers on our cost analysis, as 

well as oil industry comments, pointed out that refiners may incur additional costs not covered 
Tier 3 Summary and Analysis of Comments

7-37

by the ISBL and OSBL costs. For example, a refinery may need to add pilings to establish a 

solid foundation for its reactor and other major units if the soil is poor, the project planning and 

construction workers may require overtime pay, the refiner will incur some costs (termed 

owner costs) for planning and executing the project, and there are miscellaneous contingencies 

which must be addressed. Two of the peer reviewers suggested that we add an additional 30% 

contingency factor to capture such costs. One of the peer reviewers commented that one of the 

vendor’s costs were very similar to the costs that they use for a two stage FCC postreater 

provided that a 30 percent contingency factor is applied. Another peer reviewer suggested that 

we add a 20% contingency factor while another peer reviewer supported the capital costs that 

we used, which did not include a contingency factor, as the costs are consistent with the capital 

costs that they used in their modeling and the capital costs estimated by Mathrpo for the ICCT. 

After considering the various comments, we chose to use a 20% contingency cost factor added 

to our capital costs to account for costs that may not otherwise have been fully accounted for.

What Commenters Said:

Commenter: Marathon Petroleum Company LP (MPC)

Even though EPA criticized the Baker & O’Brien capital costs, they admitted that EPA 

received two vendor estimates for grassroots FCCU post-treating and elected to ignore the 

higher cost estimate.

Our Response:

While we agree with the comment that we did not use the vendor cost that estimates a 

higher cost, we disagree with the comment that we should have considered the higher cost. We 

used the vendor that provided the ISBL cost estimate for a grassroots postreater for Tier 3 that 

estimated the capital costs to be $1500 per barrel per day, for a 30 thousand barrel per day unit. 

We rejected the other vendor that provided an ISBL cost estimate for a Tier 2 postreater 

(desulfurizing FCC naphtha from 800 ppm down to 75 ppm) with estimated capital costs to be 

$2894 per barrel per day for a 10 thousand barrel per day unit. When we adjusted the second 

vendor’s cost estimate to reflect a 30 thousand barrel per day unit size (to be on the same basis 

as the other estimate), the second vendor’s capital cost decreased to $1970 per barrel per day. 

The difference between the two capital cost estimates reflects the cost of installing a Tier 2 

grassroots FCC postreater ($1970 per barrel per day) compared to a grassroots Tier 3 FCC 

postreater ($1500 per barrel per day) as we described above. If we would have based our 

capital cost estimate on the second vendor that provided the capital cost for a grassroots Tier 2 

postreater, we would have overestimated the capital cost for a grassroots FCC postreater 

installed for Tier 3 by about 30%.

7.2.4. Octane Cost

What Commenters Said:
Chapter 7: Costs

7-38

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

EPA’s inadequate modeling of octane costs: For estimating the costs of the proposal, EPA 

correctly pointed out that, “the most important input is the cost making up the octane loss that 

occurs with desulfurization.” [DRIA 5.1.2 page 5-3] However, EPA then goes on to 

immediately dismiss the octane costs by assuming “the cost of octane is expected to decrease 

dramatically due to expected much larger use of ethanol under the RFS2 rulemaking”. [DRIA 

5.1.2 page 5-4] Specifically, EPA assumes that by 2017, 50% of the gasoline market is E10 and 

the other half is E15, a contested fuel authorized under a partial waiver for late model vehicles 

only.

First, it is not appropriate to assume high market penetration of a contested fuel simply because 

it makes the Tier 3 proposal more palatable from a cost perspective. It is not clear that if given 

the choice, consumers would willingly consume E15 fuel given its lower energy content and 

vehicle manufacturer statements advising against its use. It is also unclear whether the vehicle 

fleet composition and fueling infrastructure in RFG zones will be able to convert 75% of 

consumption to E15. EPA makes the assumption that since E15 does not qualify for the 1 psi 

ethanol waiver, 100% of the E15 will be sold in RFG areas, which will make E15 75% of all 

gasoline in those markets (page 7-12). 

Second, EPA’s assumption for the FCC octane loss penalty from increased desulfurization is 

overly optimistic. In Table 5-18, EPA suggests that refiners will, on average, have to reduce 

sulfur in FCC naphtha from 80 ppm to 21 ppm. Then for the vendor requests to estimate this 

cost, EPA only requested a 75 ppm to 25 ppm target. The stated rationale appears to be that a 

50-ppm reduction is close enough to the 80 to 21 calculated in their averages, even though 

octane loss is not linear with desulfurization, especially at lower sulfur levels. The final result 

in Table 5-26, is that the volume-weighted average octane loss for this target is 0.49 (R+M/2). 

In their model, this half octane number reduction translated into 0.38 cents per gallon of FCC 

naphtha (page 5-5 and table 5-41 which is incorrectly referenced). FCC naphtha is assumed to 

be 36% of the gasoline pool, making EPA’s net operating cost for octane loss an astonishingly 

low value of 0.14 cents per gallon of gasoline.

Finally, this low octane cost per gallon of gasoline does not align with the trend of market 

octane cost. By examining the spread between premium and regular grades of gasoline, and 

knowing the difference in octane value of each grade, a cost/octane gallon can be calculated. 

Figure 8 [of EPA-HQ-OAR-2011-0135-4276] shows the annual average of daily posted prices 

and makes it clear that octane is getting more expensive, even as ethanol blending has saturated 

the market. Unless the market is assumed to be inefficient, it would appear octane has value 

and it is increasing. This is in direct contradiction to EPA’s assessment that costs associated 

with octane destruction through desulfurization are largely negligible as described in the prior 

paragraph. 

Our Response:
Tier 3 Summary and Analysis of Comments

7-39

The oil industry commented that we should use the wholesale price difference between 

premium and regular gasoline grades to develop an octane cost. Using this method, they 

estimated that the cost of octane would be $1/octane number-barrel. To verify API’s estimated 

octane cost using the wholesale price difference between premium and regular gasoline grades, 

we also evaluated what the octane cost would be based on bulk pricing data differences 

between premium and regular gasoline, divided by six. Based on actual data from 2008 to 

2012, we estimated the average cost as $1.08/ octane number-barrel of gasoline. 

We believe that the premium minus regular grade pricing method for estimating octane 

cost considerably overstates the cost of making up lost octane in the FCC naphtha pool. 

Premium grade gasoline is produced in smaller batches than regular grade and must be handled 

specially and separately to avoid compromising its octane content, and is transported in smaller 

batches. For example, when shipping premium gasoline in pipelines, the interface between 

premium and regular grades of gasoline must be downgraded into the regular grade gasoline to 

ensure that premium gasoline’s high octane content is not compromised – this downgrading 

increases the production cost of premium gasoline. Furthermore, the pricing between regular 

and premium grades of gasoline tends to reflect higher profit margins on premium fuel. Thus, 

if we used the wholesale price difference between premium and regular grade gasolines, we 

would be estimating the cost of not only producing the premium gasoline, but also include the 

cost for special handling of premium gasoline relative to regular grade gasoline, plus some 

profit, which is irrelevant to the cost of making up lost octane at the refinery due to Tier 3

sulfur control. 

Instead, we estimated the cost of making up the lost octane in the FCC naphtha. To do 

this we ran a control case using the Haverly LP refinery model which was run to model the 

octane loss associated with desulfurizing gasoline in the year 2018. To only capture the cost of 

the octane loss we reduced the octane value of the FCC naphtha by one octane number, and this 

was the sole change relative to the reference case. The control case was run with capital costs 

evaluated at a 15 percent rate of return on investment (ROI) after taxes.4 Unlike for the NPRM 

where commenters criticized us for assuming E15 for the FRM analysis, this case was run with 

E10 (no E15) and a small volume of E85, and we substituted 2013 natural gas liquid prices 

(ethane, propane and butane) which are much lower compared to the historical price 

relationship from previous years (the lower natural gas prices increases the octane cost 

provided by the reformer since the reformer produces natural gas liquids as byproducts). The 

octane cost estimated by the LP cost model is $0.31/octane number-barrel (0.74 c/octane 

number-gallon). Because the octane loss associated with a specific sulfur control technology 

may be lower or higher than 1 octane number, we scaled the octane cost based on the relative 

estimated octane loss on the FCC naphtha (i.e., a 1⁄2 octane loss of the FCC naphtha was 

estimated to cost $0.155/octane number-barrel. 

 

4

 Normally we conduct the refinery modeling assuming an after-tax 15% ROI and adjust the costs to reflect a 

before-tax 7% ROI to report the costs. However, in this case because the new capital investments were so 

minimal, we omitted the capital cost amortization adjustment because its effect on costs was judged to be 

negligible. 
Chapter 7: Costs

7-40

However, it was further analysis of our LP refinery modeling work which further 

explained why the price differentials between premium and regular grade gasoline overstates 

the cost of octane when the octane loss is occurring in the FCC naphtha. While the octane cost 

for making up octane loss in the FCC naphtha is $31/octane number-barrel from the LP model, 

the octane cost determined by the premium-regular grade differential using the LP model is 

$0.50/octane number-barrel, which is 60 percent higher. We believe that the LP refinery model 

is estimating a higher octane cost for the premium-regular grade differential because of the cost 

of producing premium gasoline, which is typically 6 octane numbers higher than the regular 

grade. And yet, the LP model is not capturing the additional cost inflating factors mentioned 

above such as smaller tankage, special handling and distribution and profit. Our conclusion 

from this analysis is that the premium-regular grade price differential is a poor indicator of the 

cost of making up the small amount of lost octane in FCC naphtha due to desulfurization and 

by using it would overstate the cost. Despite our confidence in the octane cost that we 

generated, we recognize the need to quantify the impacts on our costs if octane costs are indeed 

higher than what we estimated, so where we present the Tier 3 fuel cost in the Chapter 5.2 of 

the RIA for the FRM, we provide a sensitivity cost estimate assuming that octane costs 

$0.50/octane number-barrel. 

When we had our cost model peer reviewed the first time, one of the peer reviewers 

also evaluated octane cost and concluded that while recent octane costs using premium minus 

regular grade price differences were in the $1/octane number barrel range, modeled future 

octane costs for 2015 and 2020 were appreciably lower. This peer reviewer’s estimate for 

future octane costs could be much lower and provided a range of $0.25 - $0.5/octane numberbarrel. The octane cost that we are using is well within the projected octane cost range 

projected by this peer reviewer and our octane cost sensitivity case is at the high end of this 

range.

Based partially on the oil industry comments as well as our own understanding of the 

hurdles that E15 is facing for widespread implementation, we elected to base our LP refinery 

modeling octane cost case assuming E10 and a small volume of E85, but no assumed E15 

penetration. 

What Commenters Said:

Commenter: Small Business Refiners (SBR)

In addition to capital costs and increased operating expenses incurred through additional 

hydrotreating, we expect the refinery yield to decrease as a result of this change. As a result of 

desulfurization through hydrotreating, the resultant fuel octane is lower. To compensate for a 

lower octane blend component, the catalytic reformer severity must be increased to improve 

blend component octane. The net effect of this process change is a one to two percent yield loss 

on the products. 

Our Response:
Tier 3 Summary and Analysis of Comments

7-41

We agree that to the extent that refiners rely on reformers to make up for the octane loss 

due to desulfurization (instead, refiners could use alkylation units, isomerization units or blend 

in isooctane or more ethanol to make up for the lost octane), that there will be some yield loss. 

This occurs because some of the reformer feed is cracked to lighter hydrocarbons. The cost 

impact of this is reflected in our estimated octane cost. Because the reformate (the product 

from the reformer unit) is higher in energy density than the feed, the volume loss that occurs 

with reformers is somewhat offset by the higher energy density of the higher octane reformate. 

The U.S. fuels market is now in a mode of slacking gasoline demand relative to increasing 

diesel fuel demand, thus, the small reduction in gasoline yield associated with Tier 3 will have 

no perceived impact on gasoline supply. 

What Commenters Said:

Commenter: Marathon Petroleum Company LP (MPC)

EPA’s assumption for the FCC octane loss penalty from increased desulfurization is overly 

optimistic. In Table 5-18, EPA suggests that refiners will, on average, have to reduce sulfur in 

FCC naphtha from 80 ppm to 21 ppm. Then for the vendor requests to estimate this cost, EPA 

only requested a 75 ppm to 25 ppm target. The stated rationale appears to be that a 50-ppm 

reduction is close enough to the 80 to 21 calculated in their averages, even though octane loss is 

not linear with desulfurization, especially at lower sulfur levels. The final result in Table 5-26, 

is that the volume-weighted average octane loss for this target is 0.49 (R+M/2). In their model, 

this half octane number reduction translated into 0.38 cents per gallon of FCC naphtha (page 5-

5 and table 5-41 which is incorrectly referenced). FCC naphtha is assumed to be 36% of the 

gasoline pool, making EPA’s net operating cost for octane loss an astonishingly low value of 

0.14 cents per gallon of gasoline.

Our Response:

We recognized after we completed the cost analysis for the NPRM that we were not 

capturing the range of desulfurization costs experienced at refineries that had higher and lower 

levels of sulfur reduction than what the vendor data estimates (although on an average basis, 

our method of using typical desulfurization amounts is still valid). In response to comments, a 

change we made in our cost analysis for the final rulemaking is to scale the sulfur reduction 

costs based on the amount of sulfur reduction in the FCC naphtha. If the actual sulfur reduction 

was 60 ppm instead of 50 ppm that the vendor data was based on, we increased the octane loss 

and hydrogen consumption by 20 percent (60 ppm is 20% greater than 50 ppm). We also 

created a cost factor for exponentially increasing desulfurization costs above a certain 

desulfurization percentage (96% desulfurization for single stage units and 99% desulfurization 

for two stage units), which reduced the potential for underestimating desulfurization costs for 

cases of deep desulfurization.

The inclusion of additional vendor data coupled with our adjustments increased the 

volume-weighted average octane loss for a revamp of an existing FCC postreater to produce 25 

ppm FCC naphtha (to produce 10 ppm gasoline) from 0.49 (R+M)/2 to 0.77 (R+M)/2. 
Chapter 7: Costs

7-42

One reason why the octane cost number we are estimating seems “astonishing low” to 

API is API is overestimating the cost of recouping octane by basing their octane cost on the 

price differential between regular and premium grade gasoline as discussed above. 

7.2.5. Modeling Techniques

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

DRIA Cost/Benefit Analysis: EPA makes the assumption that mandated 10 ppm average sulfur 

level will result in refineries targeting exactly 10 ppm. Refinery operations do not run smoothly 

and as a result refiners must aim below the 10 ppm target, since ending the year above 10 ppm 

is unacceptable. Refineries will aim for somewhere around 8 ppm, so that an upset at the end of 

the year does not result in non-compliance for the entire year. Even with Averaging, Banking 

and Trading (ABT) program, the refineries generating credits and those using the credits will 

target around 2 ppm below the average that they must have for compliance. The ability to 

create Tier 2 sulfur credits is in part caused by this under targeting of sulfur levels. EPA of 

course assumes that the world is perfect and in that world everyone will on average achieve 

exactly 10 ppm sulfur in gasoline. The fact is that the refining industry has almost always 

overachieved when meeting mandated product specifications. EPA needs to redo their 

modeling and analysis based on an 8 ppm sulfur average to reflect real world conditions. 

Our Response:

We acknowledge that refiners could target a lower sulfur level than 10 ppm to generate 

credits for use within the company or for sale to other refining companies. However, we 

believe our assumptions are reasonable because if a refiner thought that it would not be able to 

sell the credits it generated, it would not continue to produce gasoline with less than 10 ppm 

sulfur since they would be overcomplying at a cost to the refiner. Since FCC postreaters do not 

provide any economic return, we believe that across the entire refining industry, refiners will 

target 10 ppm on average. If they were overcomplying, they would adjust their operations and 

average 10 ppm going forward to avoid the excess cost. 

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

It is well known that Linear Programming (LP) modeling approaches such as EPA’s refining 

model over optimize and underestimate refinery costs. The refinery LP approach assumes that 

the entire PADD modeled essentially has infinite trading capabilities for crude properties, final 
Tier 3 Summary and Analysis of Comments

7-43

product properties, intermediate stream properties and unit processing capabilities. For 

example, EPA’s average refinery is assumed to have a small hydrocracker when in fact most 

U.S. refineries do not have hydrocrackers. This assumption allows the notional refinery a 

multitude of processing options that are unavailable to most refineries. 

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

DRIA Cost/Benefit Analysis – Underestimated Costs: On page 5-41, EPA admits to not using 

any refinery data more recent than 2009 and therefore assuming that most refineries with sulfur 

averages above 80 ppm have an average of 30 ppm sulfur. This is a poor modeling assumption 

to start off a refinery by refinery analysis.

Our Response:

Consistent with our normal refinery modeling practice which is also responsive to these 

comments, we updated our cost analysis to more recent 2011 refinery gasoline quality and 

volume data. Since all refineries were required to comply with Tier 2 in 2011 (all the small 

refiner and geographic phase-in delays had expired at the end of 2010), we were able to use 

refinery data for each refinery’s gasoline sulfur level and not use estimates. 

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

Another mistake that EPA makes in many areas is to use average values inappropriately. EPA 

assumes that refineries process crude with average properties and designs the units in the EPA 

refinery by refinery model on that basis. EPA provides no data on which specific crudes are 

used by the refineries in this analysis. EPA fails to recognize that refinery units must be 

designed with flexibility to handle the worst crudes and the poorest quality feedstocks 

anticipated in the refinery slate. A grassroots or revamp FCCU post-treating unit designed on a 

minimal basis to handle a 100 ppm sulfur feed will not produce the required sulfur reduction 

when a 300 ppm or 500 ppm sulfur feed is used. EPA simply assumes that the high sulfur feed 

will average with the low sulfur feed but this is not the case in the real world. EPA’s use of the 

“average case” and failure to “design” for a range of refinery feedstocks, results in a constant 

bias toward underestimating refinery unit costs. 

Our Response:

We do not agree with the comment that we should not be using average crude oil 

qualities since this could affect compliance with the Tier 3 sulfur standard. These comments 

may have some relevance if we were finalizing a 10 ppm cap standard that applies in other 
Chapter 7: Costs

7-44

countries around the world. However, because the Tier 3 sulfur standard is an averaging 

standard, it is entirely appropriate to use average crude oil qualities. If, for example, a refiner 

refined a crude oil containing 2.0 weight percent (wt%) sulfur for half the year and 1.0 wt% 

sulfur for the other half the year, the refiner could assess how to comply with Tier 3 assuming 

1.5% sulfur, which is the average between the two. Assuming that the refiner had targeted a 

sulfur level of 10 ppm in its gasoline pool based on the average crude oil sulfur level, when 

refining the 1.0 wt% sulfur crude oil, the refinery will likely average about 7 ppm gasoline, and 

when refining 2.0wt% sulfur crude oil the refinery will likely average about 15 ppm gasoline. 

However, since the Tier 3 sulfur standard is an annual average standard, it would be fine for the 

refinery to average 7 ppm sulfur gasoline for half the year and 15 ppm sulfur gasoline for the 

other half of the year. The very high 80 ppm cap standard allows the refinery this flexibility. 

There may be situations where the crude oil refined by an individual refinery will result in 

higher amounts of sulfur in gasoline than what we modeled and in that case we may have 

underestimated the cost of compliance. However, our cost analysis is also most likely 

overestimating the desulfurization cost at another refinery which is refining a different crude oil 

which tends to produce gasoline with lower amounts of sulfur in the gasoline pool than what 

we modeled. Since we are estimating costs on an industry wide basis, these sorts of issues tend 

to average out across our analysis.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

DRIA Cost/Benefit Analysis – Underestimated Costs – EPA assumes that the industry cost of 

capital is 7% before taxes, which would approach 3.5% for most companies. This is compared 

to the 10% after taxes that Baker & O’Brien assumed. EPA mistakenly assumes that this ROI 

on regulatory driven refinery projects is all profit when in fact it represents the cost of obtaining 

the capital for such large projects and the opportunity cost of that capital. EPA is way off base 

with respect to the true cost of capital and the opportunity cost associated with regulatory 

driven investment. In the real world, a cost of capital of 3.5% over the life of the investment is 

far too low. 

Our Response:

The oil industry commented that the methods used for amortizing capital costs do not 

correctly represent a refiner’s investment cost.

’In OMB circular A-94, OMB directs federal departments and agencies to assess capital 

costs using a before-tax 7% ROI because it approximates the opportunity cost of capital. Also, 

OMB circular A-94 instructs federal departments and agencies to assess costs at a different ROI 

as a sensitivity analysis of another discount rate. In the RIA, we provide a cost estimate for the 

final Tier 3 gasoline sulfur standard based on an after-tax 10% ROI. An important reason for 

using the discount rate based on a before-tax 7% ROI is that all cost analysis conducted by 
Tier 3 Summary and Analysis of Comments

7-45

EPA are conducted on the same basis, which allows comparison of different environmental 

programs on the same basis.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

The MathPro study conducted for ICCT reports an average cost for PADD but in fact these are 

not average costs but the costs for an average notional refinery in each PADD. If the costs for 

refineries of different sizes fell along a straight line, this average refinery cost would be 

appropriate. However, a typical cost curve for refineries and for refinery units is exponential in 

nature not linear, as demonstrated in Figure 9 [of EPA-HQ-OAR-2011-0135-4276]. EPA 

recognizes the exponential nature of economies of scale in their equation 5-4 on page 5-34 

which incorporates the six-tenths rule. By applying this rule, curves such as EPA’s DRIA 

Figure 5-4 demonstrate that the costs are not linear and the mid-point of the curve is not 

representative of the average of all the points on the curve. Thus EPA’s own RIA analysis 

demonstrates that the MathPro approach is faulty and does not represent the real average. 

It is well known that modeling approaches such as MathPro’s notional model underestimate 

refinery costs. The notional LP approach assumes that the entire PADD modeled essentially has 

infinite trading capabilities for crude properties, final product properties, intermediate stream 

properties and unit processing capabilities. For example, MathPro’s notional refinery is 

assumed to have a small hydrocracker when in fact most U.S. refineries do not have 

hydrocrackers. This assumption allows the notional refinery a multitude of processing options 

that are unavailable to most refineries.

It should also be noted that MathPro’s use of an average notional refinery represents some 

elements of a sulfur banking and credit trading system. While it does not represent the factors 

involved in the early credit program, it does represent the final sulfur ABT system since the 

notional refinery has the average sulfur removal capacity in the PADD and achieves average 

compliance across the PADD. 

5. MathPro Inc. Refining Economics of a National Low Sulfur, Low RVP Gasoline Standard. Performed 

for The International Council For Clean Transportation. October 2011.

Commenter: Emissions Control Technology Association (ECTA)

First, EPA’s methodology is sound because it appropriately used a refinery-by-refinery cost 

model that permitted each refinery to embrace a different sulfur-reduction strategy based on its 

particular circumstances. EPA’s cost model was peer-reviewed by two refinery industry 

consultants, (17) and it was built off the model developed by Mathpro to estimate the cost of 

benzene control under MSAT2 (18). The EPA notes that the peer-review process “suggested 
Chapter 7: Costs

7-46

that there would be little to no change in [its] desulfurization cost estimate,” indicating that 

EPA’s model complied with best practices in the profession (19). 

Commenter: MathPro

These investment estimates and refining cost estimates cover de-sulfurizing the refinery 

streams needed to meet the 10 ppm average, supplying the additional hydrogen needed for desulfurization, replacing the small losses in both gasoline volume and gasoline octane that 

accompany tight de-sulfurization, and expanding refineries’ sulfur recovery in offsites is 

needed to support additional sulfur control.

We conducted our analysis using four regional refinery LP models representing projected 

aggregated refining capacity in pads one through four, with all major regulatory programs 

affecting fuel quality in place. We have used similar refinery LP models in many previous 

analyses of the refining costs of new fuel standards, including Tier 3 gasoline sulfur, ULSD, 

Federal and California RFG programs, and Arizona CBG.

In this study, our models represented the U.S. refining sector maintaining regional and total 

U.S. gasoline production at the volumes projected by EIA for 2015, meaning the refineries 

would adjust operations to replace the small losses in volume that would accompany tighter 

sulfur control. Our projected product volumes, crude oil, and natural gas prices for 2015 were 

developed from EIA’s AEO 2011.

Our Response:

We received comments in support of and against the LP refinery model. The oil 

industry commented that it was over-optimized resulting in underestimates of refinery costs. 

We also received comments in support of the model.

We disagree with the oil industry comment that EPA LP refinery modeling case was 

over optimized. The most important LP refinery modeling case that we ran for the Tier 3 

rulemaking was the octane cost case. When we analyzed that case post modeling, the refinery 

model simply increased the charge volume of heavy naphtha to reformers which were 

underutilized. This means that the refinery model only needed to estimate operational changes 

in octane level and cost which are not impacted by refinery size because capital investments in 

reforming capacity were not necessary. Thus there was no risk of the refinery model 

overoptimizing costs due to oversized assumed refinery unit (reformer) size. The second way 

that the refinery model protected against overoptimization of octane costs was by pooling 

refinery streams together, such as the light and heavy FCC catalytic naphtha. Although many 

refineries (but not all) separate the light cat (FCC) naptha from the heavy FCC cat naphtha for 

hydrotreating which allows those refineries to optimize their blending by blending them 

separately, in our refinery cost model we choose a more conservative approach by pooling the 

light and heavy cat naphtha together and blending the pooled FCC naphtha stream. This results 

in the underoptimizion of gasoline blending of FCC naphtha. Also, “That a model is limited or 

imperfect is not, in itself a reason to remand agency decisions based upon it.” Id. “It is only 

when the model bears no rational relationship to the characteristics of the data to which it is 
Tier 3 Summary and Analysis of Comments

7-47

applied that [courts] will hold that the use of the model is arbitrary and capricious.” 

Appalachian Power Company v. EPA, 135 F.3d 791, 802 (D.C. Cir. 1998)(internal citations 

omitted). 

Moreover, the oil industry failed to provide any information or data to support the 

comment that Mathpro’s LP cost analysis for ICCT, which is based on a PADD- average LP 

refinery models, over optimized costs. LP refinery models do average the costs over many 

refineries to estimate costs, but whether any LP refinery model over or under-optimizes capital 

costs depends on what unit size is chosen in the refinery modeling. If the unit size being 

modeled represents a smaller size than that of the refineries in the PADD the refinery model 

would tend to underoptimize costs. However, if the unit size modeled is larger than average, 

then the refinery model would tend to overoptimize costs. Why we say that the commenter did 

not verify whether the Mathpro refinery model overoptimized capital costs is because the 

commenter did not compare the unit size modeled to the unit sizes of the modeled refineries in 

each PADD to verify that the unit size selected was too large. Reading through the refinery 

modeling report, Mathpro discussed overoptimization of capital costs and did model a higher 

capital cost for PADD 4 refineries to capture the poorer economies of scale for those smaller 

refineries. This suggests that Mathpro did assume an FCC postreater unit size to avoid 

overoptimization.

The Mathpro refinery modeling study did not model an ABT program as the oil industry 

comment suggested because in the LP refinery model study Mathpro assumed either grassroots 

installation or revamps of FCC postreaters at each refinery. If the Mathpro cost analysis was 

modeling an ABT program, the model would have been set up to allow some refineries to 

reduce their gasoline sulfur further than required and generate credits to show compliance for 

other refineries through credit transfers to the refineries which do not take action. In this 

regard, the Mathpro refinery model explicitly did not model an ABT program.

Regardless, these comments appear directed at the Mathpro study, not at EPA’s cost 

analysis. Linear program models such as the one used by Mathpro have several advantages and 

several disadvantages compared to other modeling techniques. We have chosen for our 

analysis to develop and use a refinery-by-refinery model for our cost analysis, but which is still 

informed and aided by a refinery LP model when necessary and appropriate that is also widely 

used by industry. 

7.2.6. ABT Program Impacts on Cost

What Commenters Said:

Commenter: Emissions Control Technology Association (ECTA)

EPA accommodates an averaging, banking, and trading (ABT) mechanism that reduces the 

compliance costs by permitting “high cost” firms to meet the sulfur requirement via consuming 

credits. EPA found that many refineries with both pre- and postreaters are able to achieve sulfur 

reductions beyond the 10 ppm standard at a relatively low incremental cost and then sell the 
Chapter 7: Costs

7-48

credits to those refineries that would otherwise be faced with grassroots FCC postreater 

investments (21). Assuming counterfactually that each refinery were required to produce at 

exactly 10 ppm—that is, without the benefit of trading—EPA estimated the average 

compliance cost across all refineries to be 0.97 cents per gallon (22). With a credit-trading 

system in place, EPA estimated the average compliance cost would fall to 0.79 cents per gallon, 

with 25 refineries consuming credits. Under a more limited trading program, in which credits 

could only be exchanged within companies that owned multiple refineries, EPA estimated that 

the average cost of compliance would be 0.89 cents per gallon, with only eight refineries 

consuming credits.

EPA conservatively chose to use the estimate from this restricted, intra-firm trading regime for 

its proposal (23). Yet we believe that firms would have strong incentives to trade credits with 

other firms under Tier 3. In particular, so long as the cost of consuming a credit plus the 

transaction costs associated with inter-firm trading was less than the cost of reducing sulfur at a 

given refinery, that refinery would consume a credit from another firm. Accordingly, we expect 

the true average compliance cost to be closer to 0.79 cents per gallon. EPA’s analysis was also 

conservative in the sense that it restricted refineries that sought to reduce sulfur to achieve 

sulfur levels of precisely 10 ppm or 5 ppm, when in reality, some of those refineries could 

reduce sulfur to levels above 10 ppm (say 20 ppm) and consume credits, expanding the 

opportunities for further trading and further average cost reductions. 

Baker and O’Brien failed to properly consider the average, banking, and trading (ABT) 

provisions of EPA’s Tier 3 proposal. In particular, API imposed a rigid 20 ppm cap for each 

refinery, which eliminates many of the opportunities for trading credits (30). In contrast, EPA 

imposed a more flexible cap of 80 ppm, which permits additional gains from trading and 

thereby reduces average compliance costs (31). 

20 - EPA Proposal, Fed. Reg. at 29977.

21 - Id. at 29973.

22 - Id. at 29974.

23 - Id. at 29975.

28 - EPA Proposal, Fed. Reg. at 29978.

29 - Id.

30 - Id. at 29977. 31Id. at 29972.

Commenter: Environmental Defense Fund (EDF)

The averaging, banking, and trading (ABT) program will help achieve these low costs by 

allowing refiners to optimize their investments. And that low cost estimate assumes that less 

than a quarter of the 111 existing refiners will participate in the ABT program. [This statement 

also cross-referenced with section 5.5.1]

Commenter: National Association of Clean Air Agencies (NACAA)

Opponents of Tier 3 contend that the cost of low-sulfur fuel will be not less than a penny a 

gallon, but between 6 cents and 9 cents per gallon. However, in making this estimate they did 
Tier 3 Summary and Analysis of Comments

7-49

not account for the mitigating impacts of EPA’s proposed set of flexibilities, all of which have 

proven successful in prior fuel programs adopted by the agency (e.g., lowering gasoline vapor 

pressure).

These include 1) an annual average sulfur standard with an ability to use a higher per-gallon 

cap; 2) an averaging, banking and trading program that would allow refiners six years —

January 1, 2014 through December 31, 2019 — over which to spread out their investment and 

receive credit for early compliance by over complying with the current 30-ppm average sulfur 

standard from 2014 through 2016; 3) relief for small refiners and refineries — those producing 

fewer than 75,000 barrels a day — in the form of a three-year delay in compliance until 

December 31, 2019; and 4) relief for economic and technical hardship, available to all refiners.

Our Response:

We agree with the comments that the flexibilities inherent in the ABT program lowers 

the cost of complying with Tier 3 and will ease compliance with the Tier 3 program start date. 

As summarized above in Chapter 7.2.2.1 of this Summary and Analysis of Comments 

document, the ABT program is estimated to reduce the cost of the Tier 3 sulfur program by 

about 25%. As we discuss in Chapter 5.1.4.3 of this document, the flexibilities offered by the 

ABT program will enable refiners to earn early sulfur reduction credits prior to the program 

start date which will provide refiners the flexibility to start up their grassroots or revamped 

FCC postreaters that fits best in the schedule for installing and tying in the capital additions at 

each refinery.

7.2.7. Other Issues

What Commenters Said:

Commenter: Pennsylvania Department of Environmental Protection (DEP)

The EPA should examine whether damage will occur to seals on gas station equipment or other 

equipment. It is always a risk that equipment will be affected when fuel specifications change. 

These risks do not appear to have been considered in the proposed rulemaking. Lower levels of 

sulfur could cause some older gaskets in engines and equipment to leak. Additionally, although 

EPA does not address the 15 percent volume content of ethanol fuel directly in this proposed 

rule, the agency does indicate that it believes that 15 volume percent ethanol will eventually be 

in widespread use. EPA should factor in the potential cost from damage that could occur as a 

result of increasing ethanol content to 15 volume percent. EPA has failed in this proposed Tier 

3 rule and in its earlier ethanol rule to address potential costs and emissions that will result if 

the higher ethanol content fuel causes damage to gasoline storage and dispensing equipment or 

other types of highway and nonroad equipment. Alcohol can degrade plastic, rubber and some 

types of metals. 

Our Response:
Chapter 7: Costs

7-50

Tier 3 sulfur control is not expected to cause other fuel changes that might have any 

impacts on vehicles and engines. The only expected impact of the sulfur control is the benefits 

to the operation of the catalytic aftertreatment systems that are intended by the sulfur standard. 

Concerns with respect to E15 ethanol blends or other fuels are outside the scope of this 

rulemaking.

7.3. Cost Effectiveness of the Tier 3 Standards

What Commenters Said:

Commenter: American Petroleum Institute and American Fuel and Petrochemical 

Manufacturers

In their comments, API and AFPM argued EPA’s cost-effectiveness analysis is fundamentally 

flawed. They state that, “in assessing cost-effectiveness, EPA simply computes the costs 

incurred in the years 2017 and 2030 and divides those costs by the emission reductions it 

estimates will occur in those years. This approach is simply incorrect.” They go on to say that, 

“under the approach used by EPA in the RIA, the compliance cost for a given year represents 

only the costs for new vehicles sold in that year; those costs are then divided by the cumulative 

emission reductions achieved by the regulation, which include benefits from previous modelyear vehicles.” 

Commenter: Marathon Petroleum Company LP (MPC)

In their comments, Marathon argues that the proposal’s cost effectiveness analysis was 

inconsistent with OMB guidelines. Marathon notes that OMB states that the three basic 

elements of a good regulatory analysis should include: 1) a statement of the need for the 

proposed action; 2) an examination of alternative approaches, and; 3) an examination of 

benefits and costs of the proposed action and the main alternatives (OMB Circular A-4, page 

2). EPA’s draft RIA does not include an examination of alternative approaches and fails to 

meet the above basic criteria.

Marathon notes that, for major rule-makings, OMB recommends providing both a benefit cost 

analysis (BCA) and a cost-effectiveness analysis (CEA) (OMB Circular A-4, page 9). 

Marathon argues that, even though Tier 3 is a major rule, EPA did not provide a CEA that 

addresses alternative measures to reduce PM2.5 and ozone air pollution, costs of alternate 

measures, and cost comparisons and, without a CEA, EPA cannot determine if the Tier 3 rule is 

the most cost effective way to reduce PM2.5 or ozone air pollution. 

Our Response:

We acknowledge that the analysis presented in the proposal as a cost-effectiveness 

analysis was not a “cost-effectiveness” analysis in the way the commenter is using the term and 

should have been described as a “cost per ton-reduction” analysis. The numbers in proposed 
Tier 3 Summary and Analysis of Comments

7-51

preamble Table VII-9 (see 78 FR 29979) are, in fact, the annual costs of the program in the 

indicated year divided by the tons reduced by the program in that given year. 

That being said, a cost-effectiveness analysis is not a requirement of the Clean Air Act 

sections under which our Tier 3 regulatory authority resides. We are required to give 

appropriate consideration to cost, among other factors, when issuing vehicle standards under 

section 202(a) of the Clean Air Act, but the statute does not prescribe a cost-effectiveness 

analysis. Similarly, section 211(c)(1) of the Clean Air Act, which is our statutory authority to 

issue fuel standards makes no mention of a need to demonstrate the cost-effectiveness of the 

fuel standards. While a cost-effectiveness analysis is not a statutory requirement, we 

nonetheless have sometimes presented cost/ton-reduced numbers in the supporting analyses for 

regulations that we issue. “Because section 213 does not mandate a specific method of cost 

analysis, we find reasonable the EPA's choice to consider costs on the per ton of emissions 

removed basis.” Husqvarna AB v. EPA, 254 F. 3d 195 at 200 (D.C. Cir. 2001)).

What Commenters Said:

Commenter: American Petroleum Institute and American Fuel and Petrochemical 

Manufacturers:

In their comments, API and AFPM claim that EPA has not performed the incremental costeffectiveness analysis required to establish that individual portions of the Tier 3 Proposal are cost 

effective. They state that, “the vehicle standards and sulfur reduction elements of the Tier 3 

program are severable, as either could be implemented by EPA without the implementation of the 

other. Given this, EPA should have assessed the costs and benefits of each element individually so 

that the need for each element could be assessed based on its relative contribution to the overall 

benefits expected from the Tier 3 proposal and in light of its relative contribution to the overall 

costs.”

They also claim that the fuel sulfur control provisions of the Tier 3 proposal provide only a small 

portion of the total expected health benefits and are therefore “expected to be much less cost 

effective than the proposed vehicle standards.”

Commenter: Chevron Products Company

In their comments, Chevron states that they do not believe that the reduction in annual average 

gasoline sulfur from 30 ppm to 10 ppm is warranted based on tailpipe emissions and cost 

effectiveness. Chevron states their belief that that the reduction in annual average gasoline 

sulfur from 30 ppm to 10 ppm is not warranted based on tailpipe emissions and cost 

effectiveness. 

Chevron also states that EPA’s cost-benefit analysis is based on an assumption that a sulfur 

level of 10 ppm is necessary to obtain the claimed benefits. Since EPA did not test at an 

intermediate sulfur level, there was insufficient data available at the time the NPRM was 

written to properly determine whether to set the new standard at 10 ppm or some intermediate 

level between 10 and 30 ppm. 
Chapter 7: Costs

7-52

Chevron also states that the NPRM does not discuss the cost-effectiveness of the program as a 

whole (vehicles and fuels) with a sulfur level between 10 and 30 ppm and that there is no 

compelling argument for why the sulfur level should be 10 ppm and not somewhere in 

between. 

Commenter: Countrymark

In their comments, Countrymark argues that the Tier 3 reduction in gasoline sulfur will be 

significantly more expensive per pound of sulfur removal, than previous regulations. They state 

that the Tier 2 sulfur reductions cost approximately $100,000 per ppm of sulfur, while Tier 3 

sulfur reductions are expected to cost $900,000 to $1,000,000 per ppm of sulfur. 

Our Response:

EPA disagrees with the commenters’ claim that the vehicle and fuel programs are 

“severable, as either could be implemented by EPA without the implementation of the other.” 

For both the proposal and the final rulemaking, EPA analyzed the combined fuel and vehicle 

program, in keeping with the fundamental principles of the Tier 3 program: that vehicles and 

fuels should be treated as an integrated system, as has been successfully done in the mobile 

source emission control program for over a decade.

As described in detail in Sections I.A and IV.A.6 of the preamble to the final rule, there 

is a first-order relationship between fuel sulfur content and the efficiency of modern three-way 

catalytic converters. The Tier 3 final rulemaking addresses the stringency of exhaust gas 

standards and fuel sulfur level as a system because, as documented in the scientific literature 

and more fully described in Section IV.A.6 of the preamble to the final rule, the two are 

strongly linked. For this reason, it is not possible to ascribe emission reductions, air quality and 

human health benefits to the vehicle program independent of the sulfur program (or vice versa), 

because the new vehicle program depends on the reduced sulfur level of the fuel program.

While it is not possible to identify the air quality impacts, health effects, or benefits of a 

fuel sulfur program independent of a vehicle program, the final rulemaking contains a 

significant amount of analysis that distinguishes between the emission reductions associated 

with the fuel program on the existing fleet (pre-Tier 3 vehicles) and the emission reductions 

associated with the vehicle and fuel programs on the new fleet (Tier 3 vehicles). See preamble 

Section III.B of the preamble for these emission impacts. 

In addition to the impacts of fuel sulfur standards alone on the pre-Tier 3 fleet and the 

impacts of fuel sulfur standards and vehicle standards combined on the Tier 3 fleet presented in 

Tables III-2 through III-4 of the preamble, EPA has also conducted air quality modeling for 

2018 in order to understand the immediate impacts of the Tier 3 standards. The air quality 

impacts in 2018 are mostly due to the impact of the fuel sulfur program on the existing fleet, 

reflecting the corresponding reduction in emissions. These air quality modeling results are 

presented in detail in Section III.C of the preamble to the final rule and RIA Chapter 7. Finally, 

we performed an illustrative analysis of monetized impacts associated with the final rulemaking

in 2018 (See Section VIII.E of the preamble to the final rule and RIA Chapter 8.1.4). Total 

benefits in 2018 are estimated to be between $1.9 and $5.6 billion, depending on the suite of 
Tier 3 Summary and Analysis of Comments

7-53

health impact studies and discount rates used. Total benefits in 2030 are estimated to be 

between $6.7 and $19 billion.

The final rulemaking analysis also estimates the costs of the vehicle and sulfur 

programs both separately and combined, for both 2018 and 2030. 

The Tier 3 final rulemaking presents substantial and transparent analysis of the impacts 

of the vehicle and sulfur standards, and the results of this analysis demonstrate the estimated 

benefits of the final standards clearly outweigh the projected costs.

Further, as described in Section IV of the preamble, we believe that 10 ppm sulfur is 

required to enable the Tier 3 standards. We see no reason to have analyzed the costs and 

emission reductions of sulfur levels between 10 and 30 ppm, as suggested by Chevron, given 

that the vehicle program would not be feasible at those intermediate sulfur levels. We received 

similar comments – that EPA should have considered sulfur levels between 10 and 30 ppm –

and summarize them and respond to them in Chapter 4.1.4.3 of this Summary and Analysis of 

Comments document.

Lastly, we do not see the relevance of comparisons between the Tier 2 and Tier 3 

programs in terms of costs per ppm of sulfur reduction. Both programs are feasible, provide 

significant public health benefits and do so at reasonable costs.
Tier 3 Summary and Analysis of Comments

8-1

8. Estimated Benefits of the Proposed Rule

What We Proposed:

The comments in this chapter correspond to Section VIII of the preamble to the proposed 

rule and address the estimated benefits of the Tier 3 program. A summary of the comments 

received and our response to those comments are located below.

8.1. Comments on Benefits Methods and Assumptions

What Commenters Said:

Commenter: Institute for Energy Research (IER)

Second, EPA is required to publish key pieces of information when it proposes a new rule. 

Specifically, EPA shall provide a summary of “the factual data on which the proposed rule is 

based” and “the methodology used in obtaining the data and in analyzing the data.”3 EPA has 

failed to comply with this requirement. For example, the vast majority of benefits from this rule 

come from reductions in particulate matter, but EPA has consistently refused to release the data 

upon which it relies for these benefits calculations to the public. This failure is in clear violation 

of President Obama’s claim that his administration is “the most transparent administration in 

history’. 

Our Response:

The Tier 3 final rulemaking presents substantial and transparent analysis of the impacts 

of the vehicle and sulfur standards, and the results of this analysis demonstrate the estimated 

benefits of the final standards clearly outweigh the projected costs. For both the proposal and the 

final rulemaking, we provide factual data on which the rulemaking is based, both in the preamble 

and Regulatory Impact Analysis. We also provide extensive documentation of our data, 

methods, and underlying assumptions in the docket that accompanies this rule (EPA-HQ- OAR–

2011–0135).

We also reject the commenter’s claim that EPA has consistently refused to release the 

underlying data that supports the PM2.5 benefits analysis. The peer-reviewed scientific evidence 

that particulate matter (and ozone) are associated with significant public health impacts is robust, 

well-understood, and has been documented extensively in the rulemaking package (for example, 

see Chapter 6 and Chapter 8 of the RIA).

Questions have been raised in specific regard to the underlying data associated with the 

PM-related mortality studies EPA uses in its risk and benefits analyses (the American Cancer 

Society and Harvard Six Cities cohort studies). The data are held by the outside research 

institutions that conducted these large-scale epidemiological studies, not the EPA, and the 

Agency has released all of the data that we have received thus far from those institutions. The 

Agency is also engaged with the relevant research institutions to get access to additional data.
Chapter 8: Benefits

8-2

We emphasize, however, that the fact that some of the data is not currently public in no 

way undermines the validity of the studies’ results. Nor does it call into question the EPA’s 

reliance on those studies, along with thousands of other peer-reviewed studies, when the agency 

considers the scientific foundation regarding methods used in risk and benefits assessments. In 

fact, the original studies based on these cohorts already have been subject to reanalysis and 

validation by the Health Effects Institute (HEI). HEI entered into confidentiality agreements 

with the owners of the data to have access to the data in order to conduct a reanalysis of the study 

cohorts. The reanalysis confirmed the validity of the findings and methodology.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Implausible health benefits due to highly conservative, unrealistic assumptions:

Using more realistic assumptions per existing references, the economic benefits of this proposed 

rule would be markedly reduced lower than the costs in the proposed rule. Additionally, the 

DRIA does not comply with various sections of the OMB Circular A-4 guidelines. The 

references used in this section can be found in the Appendix [EPA-HQ-OAR-2011-0135-4276].

Our Response:

We base our analysis of the program’s impact on human health and the environment on 

peer-reviewed studies of air quality and human health effects.1,2,3 Our benefits methods are 

consistent with the Regulatory Impact Analyses (RIAs) that accompanied the final revisions to 

the National Ambient Air Quality Standards (NAAQS) for Particulate Matter, the 2008 final 

ozone NAAQS, and the 2010 ozone NAAQS reconsideration. 

These benefits methods are fully consistent with Circular A-4

4

and EPA guidance.

5

However, we note that Circular A-4 provides guidance to Federal agencies on the development 

of regulatory analyses under Executive Orders 12866 and 13563 and does not establish legally 

enforceable requirements.

 

1 U.S. Environmental Protection Agency. (2012). Regulatory Impact Analysis for the Final Revisions to the 

National Ambient Air Quality Standards for Particulate Matter. Prepared by: Office of Air and Radiation, EPA452/R-12-005. Retrieved November 22, 2013 at http://www.epa.gov/ttn/ecas/ria.html

2 U.S. Environmental Protection Agency. (2008). Final Ozone NAAQS Regulatory Impact Analysis. Prepared by: 

Office of Air and Radiation, Office of Air Quality Planning and Standards. Retrieved November 22, 2013 at 

http://www.epa.gov/ttn/ecas/ria.html. EPA-HQ-OAR-2009-0472-0238

3 U.S. Environmental Protection Agency. (2010). Summary of the updated Regulatory Impact Analysis (RIA) for the 

Reconsideration of the 2008 Ozone National Ambient Air Quality Standard (NAAQS). Prepared by: Office of 

Air and Radiation, Office of Air Quality Planning and Standards. Retrieved November 22, 2013 at 

http://www.epa.gov/ttnecas1/regdata/RIAs/s1-supplemental_analysis_full.pdf.

4 Office of Management and Budget (OMB). 2003. Circular A-4: Regulatory Analysis. Washington, DC. Available

on the Internet at <http://www.whitehouse.gov/omb/circulars/a004/a-4.html.>

5 U.S. Environmental Protection Agency (U.S. EPA). 2010. Guidelines for Preparing Economic Analyses. EPA 240-

R-10-001. National Center for Environmental Economics, Office of Policy Economics and Innovation. 

Washington, DC. December. Available on the Internet at <http://yosemite.epa.gov/ee/epa/eerm.nsf/vwAN/EE0568-50.pdf/$file/EE-0568- 50.pdf>.
Tier 3 Summary and Analysis of Comments

8-3

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Inflated economic benefits based on “avoided or premature mortality”:

To monetize the mortality related benefits, EPA continues to use the inappropriate metric of 

“avoided deaths” and the Value of a Statistical Life (VSL). This approach is inconsistent with the 

older age of the population most impacted by air pollution (Sunstein et al. 2004; Rabl et al. 2003 

and 2006; Leksell and Rabl 2001). EPA VSL-only approach is also inconsistent with OMB 

guidelines which call for the presentation of results of mortality valuation using both the value of 

statistical life year (VSLY) or similar metric such as value of a life year (VOLY) and VSL 

(OMB Circular A-4, page 30). This single factor resulted in an approximate 5-fold over 

estimation of the mortality benefits versus those that would have been resulted if EPA used a 

VOLY figure such as the one from Aldi and Viscusi (2007). If EPA used the VOLY or a similar 

approach as recommended by OMB and held all other assumptions constant, the costs and 

benefits of the rule would be about the same. 

It is worth noting that EPA is the only regulatory authority worldwide that uses a VSL only 

approach to assess the economic impacts of mortality attributed to air pollution. In the European 

Union, both the VSL and VOLY approaches are used. The VOLY is the approach preferred by 

UK Institute of Occupational Medicine, the group that develops health component of the cost 

benefit analysis for the Clean Air for Europe program. The World Health Organization uses a 

quality adjusted life year approach to assess impacts of air pollution. 

EPA’s 8.0 to 9.9 M$ VSL figures are by far the highest used worldwide and nearly an order of 

magnitude higher than the 1 M Euro figure used to assess the economic impacts/ benefits of air 

pollution reduction policies in Europe, a region with an economy and population characteristics 

similar to the U.S. 

Even though hedonic wage studies are not applicable for air pollution control policy 

development, EPA inappropriately used them to derive recommended VSL for the Tier 3 DRIA. 

As noted by Fraas and Lutter (2012), the inclusion of hedonic wage studies results in a two-fold 

inflation of the VSL figure currently used by EPA. 

EPA again used the same limited approach to assess uncertainty and did not provide a 

quantitative analysis of the key uncertainties that drive the very high benefits figures. Some of 

the key uncertainties that were not addressed include: ... 4) the impact of using a high end versus 

a more central VSL and the impact of using the more policy relevant VOLY metric to monetize 

loss of life expectancy. 

Our Response:
Chapter 8: Benefits

8-4

Regarding the application of a Value of Statistical Life (VSL) versus a Value of 

Statistical Life Year (VSLY) approach as an appropriate metric, OMB Circular A-4 suggests that 

agencies consider quantifying life years, but it does not require an agency to do so. The EPA has 

explored the issue of remaining life expectancy and its potential effect on WTP in the past and 

has received guidance from the Science Advisory Board (SAB) on the matter.

6

To summarize, 

the SAB concluded that economic theory is ambiguous on how people’s willingness to pay to 

reduce mortality risks should change over their lifetime, leaving it therefore as an empirical 

matter. The judgment of the SAB, however, is that the empirical literature is not advanced 

enough to provide clear guidance on how age and health status affect willingness to pay to 

reduce mortality risks and that “...the use of a constant Value of a Statistical Life Year (VSLY), 

which assumes that the VSL is strictly proportional to remaining life expectancy, is 

unwarranted.” (p. ii) Instead, the SAB recommended that EPA use an age-independent valuation 

of mortality risk reductions (an age-independent VSL), which the EPA has done here. This is 

also consistent with EPA’s Economic Guidelines, which conclude that, for the present time, the 

appropriate default approach for valuing the benefits of reductions in mortality risk is provided 

by a central VSL estimate.

EPA’s VSL approach for monetizing benefits from reductions in mortality risk (including 

sources of estimates and methods for adjustment over time) has been peer reviewed by the SAB. 

The 26 estimates underlying EPA’s guidance for Willingness to Pay (WTP) for mortality risk 

reductions come from Viscusi (1992),7 which describes the selection criteria for the studies that 

EPA originally used in The Benefits and Costs of the Clean Air Act: 1970 to 1990.

8 Most of the 

estimates in this set of literature are based on wage differentials for workplace risks. While these 

estimates cannot be taken as precise values for mortality risk reductions from environmental 

policies, their usefulness for informing environmental policy analysis has been recognized 

repeatedly by the Environmental Economics Advisory Committee of the SAB (SAB-EEAC).

9,10

In the context of re-evaluating Agency guidance on this issue, EPA examined multiple 

meta-analyses published in the economics literature and consulted with the SAB-EEAC on how 

to evaluate and apply meta-analyses of mortality risk valuation studies in a policy context. 

Specifically, when asked whether EPA guidance on the issue should rely on stated preference or 

 

6 U.S. Environmental Protection Agency—Science Advisory Board (U.S. EPA-SAB). 2007. SAB Advisory on 

EPA’s Issues in Valuing Mortality Risk Reduction. EPA-SAB-08-001. October. Available on the Internet at 

<http://yosemite.epa.gov/sab/sabproduct.nsf/4128007E7876B8F0852573760058A978/$File/sab-08-001.pdf>.

7 Viscusi, W.K. 1992. Fatal Tradeoffs: Public and Private Responsibilities for Risk. New York, NY: Oxford 

University Press.

8 U.S. Environmental Protection Agency (EPA). 1997. The Benefits and Costs of the Clean Air Act, 1970 to 1990. 

Prepared for U.S. Congress by U.S. EPA, Office of Air and Radiation/Office of Policy Analysis and Review, 

Washington, DC.

9 U.S. Environmental Protection Agency—Science Advisory Board (U.S. EPA-SAB). 2000. An SAB Report on 

EPA’s White Paper Valuing the Benefits of Fatal Cancer Risk Reduction. EPA-SAB-EEAC-00-013. July. 

Available on the Internet at 

<http://yosemite.epa.gov/sab%5CSABPRODUCT.NSF/41334524148BCCD6852571A700516498/$File/eeacf01

3.pdf>.

10 U.S. Environmental Protection Agency (U.S. EPA). 2010. Guidelines for Preparing Economic Analyses. EPA 

240-R-10-001. National Center for Environmental Economics, Office of Policy Economics and Innovation. 

Washington, DC. December. Available on the Internet at <http://yosemite.epa.gov/ee/epa/eerm.nsf/vwAN/EE0568-50.pdf/$file/EE-0568- 50.pdf>.
Tier 3 Summary and Analysis of Comments

8-5

hedonic wage studies, the SAB-EEAC responded, “[t]he SAB believes that both stated 

preference and revealed preference studies should be considered in valuing mortality risks ... 

Both approaches have strengths and weaknesses in a particular context, and, as a result, we do 

not believe that the Agency should rely exclusively on one or the other in all contexts.”11

More recently, in the context of reviewing EPA’s strategy for updating mortality risk 

valuation estimates in the future, the SAB supported combining the two streams of literature to 

arrive at estimates for use in regulatory analysis, stating “...to the extent that each literature 

provides useful information about the VRR [Value of a Risk Reduction] in a particular context, 

or the variation of VRR between contexts, it is important to combine their results.”12

Regarding the comment that EPA should examine the impact of using a high end versus a 

more central VSL, we do indeed examine this impact in our probabilistic uncertainty analysis. 

The EPA currently recommends a central VSL of $8.3m (1990$, 1990 income) based on a 

Weibull distribution fitted to 26 published VSL estimates (5 contingent valuation and 21 labor 

market studies). The underlying studies, the distribution parameters, and other useful information 

are available in Appendix B of the EPA’s Guidelines for Preparing Economic Analyses.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

EPA also inappropriately scaled up the VSL over time based on the assumption that there will be 

a continuing increase in real income in the United States. As a result, in the draft DRIA, EPA 

used a VSL figure that grew from $8.0 million in 2000 to $9.9 million in 2030. EPA’s 

assumption defies recent economic trends as reported by the United States Census Bureau 

(2012). Adjusted for inflation, the average median household income in the United States has 

steadily declined each year over the last four years, falling from $54,489 in 2007 to $50,054 in 

2011. 

Our Response:

Our analysis accounts for expected growth in real income over time. This is a distinct 

concept from inflation and currency year. Economic theory argues that Willingness to Pay 

(WTP) for most goods (such as environmental protection) will increase if real incomes increase. 

 

11 U.S. Environmental Protection Agency—Science Advisory Board (U.S. EPA-SAB). 2007. SAB Advisory on 

EPA’s Issues in Valuing Mortality Risk Reduction. EPA-SAB-08-001. October. Available on the Internet at 

<http://yosemite.epa.gov/sab/sabproduct.nsf/4128007E7876B8F0852573760058A978/$File/sab-08-001.pdf>.

12 U.S. Environmental Protection Agency—Science Advisory Board (U.S. EPA-SAB). 2011. Review of Valuing 

Mortality Risk Reductions for Environmental Policy: A White Paper (December 10, 2010). EPA-SAB-11-011 

July. Available on the Internet at 

<http://yosemite.epa.gov/sab/sabproduct.nsf/298E1F50F844BC23852578DC0059A616/$File/EPA-SAB-11-011-

unsigned.pdf>.
Chapter 8: Benefits

8-6

There is substantial empirical evidence that the income elasticity13 of WTP for health risk 

reductions is positive, although there is uncertainty about its exact value. Thus, as real income 

increases, the WTP for environmental improvements also increases. Although many analyses 

assume that the income elasticity of WTP is unit elastic (i.e., a 10% higher real income level 

implies a 10% higher WTP to reduce risk changes), empirical evidence suggests that income 

elasticity is substantially less than one and thus relatively inelastic. As real income rises, the 

WTP value also rises but at a slower rate than real income.

The effects of real income changes on WTP estimates can influence benefits estimates in 

two different ways: through real (national average) income growth between the year a WTP 

study was conducted and the year for which benefits are estimated, and through differences in 

income between study populations and the affected populations at a particular time. The SABEEAC advised the EPA to adjust WTP for increases in real income over time but not to adjust 

WTP to account for cross-sectional income differences “because of the sensitivity of making 

such distinctions and because of insufficient evidence available at present.”

14 An advisory by 

another committee associated with the SAB, the Advisory Council on Clean Air Compliance 

Analysis (SAB-Council), has provided conflicting advice. While agreeing with “the general 

principle that the willingness to pay to reduce mortality risks is likely to increase with growth in 

real income” and that “[t]he same increase should be assumed for the WTP for serious nonfatal 

health effects,” they note that “given the limitations and uncertainties in the available empirical 

evidence, the Council does not support the use of the proposed adjustments for aggregate income 

growth as part of the primary analysis.”

15 Until these conflicting advisories have been reconciled, 

the EPA will continue to adjust valuation estimates to reflect income growth.

The agency continues to update its income elasticity and income growth estimates using 

the available projections in growth, including GDP growth.

What Commenters Said:

Commenter: Marathon Petroleum Company LP (MPC)

Furthermore, OMB recommends that agencies use multiple measures of effectiveness (OMB 

Circular A-4, page 13) including at least one integrated measure of effectiveness such as Quality 

 

13 Income elasticity is a common economic measure equal to the percentage change in WTP for a 1% change in 

income.

14 U.S. Environmental Protection Agency—Science Advisory Board (U.S. EPA-SAB). 2000. An SAB Report on 

EPA’s White Paper Valuing the Benefits of Fatal Cancer Risk Reduction. EPA-SAB-EEAC-00-013. July. 

Available on the Internet at 

<http://yosemite.epa.gov/sab%5CSABPRODUCT.NSF/41334524148BCCD6852571A700516498/$File/eeacf01

3.pdf>.

15 U.S. Environmental Protection Agency—Science Advisory Board (U.S. EPA-SAB). 2004. Review of the Draft 

Analytical Plan for EPA’s Second Prospective Analysis—Benefits and Costs of the Clean Air Act, 1990-2020: 

An Advisory by the Advisory Council for Clean Air Compliance Analysis. EPA-SAB-COUNCIL-ADV-04-004. 

May. Available on the Internet at 

<http://yosemite.epa.gov/sab/sabproduct.nsf/7CCBBFE15CD4C8B185256F17005E3079/$File/council_adv_040

04.pdf>.
Tier 3 Summary and Analysis of Comments

8-7

Adjusted Life Year if the rule claims both mortality and morbidity benefits (Circular A-4, page 

12). As mentioned above, EPA only used a VSL to monetize mortality in this rule and the draft 

rule does claim morbidity benefits. Therefore, EPA’s VSL only approach does not comply with 

two separate sections of OMB guidelines as described in Circular A-4.

Our Response:

As we note in Chapter 7.3 of this document, a cost-effectiveness analysis is not a 

requirement of the Clean Air Act sections under which our Tier 3 regulatory authority resides. 

We are required to give appropriate consideration to cost, among other factors, when issuing 

vehicle standards under section 202(a) of the Clean Air Act, but the statute does not prescribe a 

cost-effectiveness analysis. Similarly, our statutory authority to issue fuel standards makes no 

mention of a need to demonstrate the cost-effectiveness of the fuel standards (see section 

211(c)(1) of the Clean Air Act). We do, however, conduct a Cost Benefit Analysis (CBA), 

which is entirely consistent with OMB guidance.

Furthermore, Circular A-4 does not require agencies to conduct a cost-effectiveness 

analysis: “...you should prepare a cost-effectiveness analysis ... to the extent that a valid 

effectiveness measure can be developed to represent expected health and safety outcomes [p. 

9].”16 According to EPA’s economic guidelines:

“The fields of health economics and public health often account for health status through 

the use of quality-adjusted life years (QALYs) or disability adjusted life years (DALYs). 

These measures have their place in evaluating the cost-effectiveness of medical 

interventions and other policy contexts, but have not been fully integrated into the 

welfare economic literature on risk valuation.”17

In conclusion, EPA’s use of the VSL to monetize the reductions in premature mortality is 

fully consistent with Circular A-4 and EPA guidance.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Inappropriately monetized health effects not caused by PM2.5:

In the DRIA as per all recent air related RIAs, EPA monetized a large number of health effects 

that have clearly not been established to be caused by PM or ozone. The most significant of these 

from an economic perspective is chronic bronchitis attributed to exposure to PM2.5. 

 

16 Office of Management and Budget (OMB). 2003. Circular A-4: Regulatory Analysis. Washington, DC. Available 

on the Internet at <http://www.whitehouse.gov/omb/circulars/a004/a-4.html.>

17 U.S. Environmental Protection Agency (U.S. EPA). 2010. Guidelines for Preparing Economic Analyses. EPA 

240-R-10-001. National Center for Environmental Economics, Office of Policy Economics and Innovation. 

Washington, DC. December. Available on the Internet at <http://yosemite.epa.gov/ee/epa/eerm.nsf/vwAN/EE0568-50.pdf/$file/EE-0568- 50.pdf>.
Chapter 8: Benefits

8-8

To estimate the incidence of chronic bronchitis, EPA relied on a very poor quality and outdated 

study (Abbey et al. (1999). This study examined oxidative air pollution in southern California 

over three decades ago. Abbey et al. did not evaluate fine PM but rather a different NAAQS 

pollutant, total suspended particulates. EPA inappropriately converted the risks attributed to 

course PM in Abbey et al. to fine PM. With this approach, EPA ignored well-known medical 

knowledge that bronchitis is a disease of the upper airway where larger particles deposit. It is 

unlikely that exposure to fine PM influence the development of bronchitis. Since Abbey et al. did 

not report a statistically significant increase in bronchitis due to exposure to PM, EPA used a 

non-statistically significant finding to estimate bronchitis incidence due to fine PM exposure. 

Our Response:

We base our analysis of the program’s impact on human health and the environment on 

peer-reviewed studies of air quality and human health effects.18,19 Our benefits methods are 

consistent with the RIA that accompanied the final revisions to the National Ambient Air Quality 

Standards (NAAQS) for Particulate Matter and the final ozone NAAQS. As a result of this 

update to be consistent with the PM NAAQS analysis, we have removed the quantification of 

chronic bronchitis from our main analysis. This change is consistent with the findings of the PM 

Integrated Science Assessment (ISA) that the evidence for an association between long-term 

exposure to PM2.5 and respiratory effects is more tenuous.20

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

No estimates of Tier 3 impacts on urban populations.

Our Response:

This is an incorrect statement, since EPA’s impacts analysis – including emissions, air 

quality, and health benefits – cover the national impacts of the final rulemaking, including both 

urban and rural areas (the contiguous 48 state area for the air quality modeling and benefits 

analysis).

 

18 U.S. Environmental Protection Agency. (2012). Regulatory Impact Analysis for the Final Revisions to the 

National Ambient Air Quality Standards for Particulate Matter. Prepared by: Office of Air and Radiation, EPA452/R-12-005. Retrieved August 14, 2013 at http://www.epa.gov/ttn/ecas/ria.html

19 U.S. Environmental Protection Agency. (2008). Final Ozone NAAQS Regulatory Impact Analysis. Prepared by: 

Office of Air and Radiation, Office of Air Quality Planning and Standards. Retrieved March, 26, 2009 at 

http://www.epa.gov/ttn/ecas/ria.html. EPA-HQ-OAR-2009-0472-0238

20 U.S. Environmental Protection Agency (U.S. EPA). 2009b. Integrated Science Assessment for Particulate Matter 

(Final Report). EPA-600-R-08-139F. National Center for Environmental Assessment—RTP Division. 

December. Available on the Internet at <http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=216546>.
Tier 3 Summary and Analysis of Comments

8-9

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Insufficient quantification of key uncertainties in claimed benefits:

The quantitative treatment of uncertainty was extremely limited. As has become standard for all 

recent EPA RIAs, here EPA only presented a simple range of figures based on whether they used 

the results of Pope et al. (2002) or Laden et al. (2006) to assess chronic PM mortality. EPA did 

not address the full range of uncertainty in this single factor, i.e. the PM mortality concentration 

response relationship. As noted above, EPA excluded from consideration many other studies that 

report a different range of results.

Similarly, for ozone, the only uncertainty EPA attempted to address quantitatively was the 

magnitude of the acute ozone mortality risk function. Again, EPA did not address this issue 

thoroughly. Rather, EPA selected two positive studies and excluded from consideration many 

other studies that provided a different spectrum of results. 

As pointed out by Frass and Lutter (2012), EPA’s current approach to assess uncertainties 

focuses narrowly on the PM and ozone mortality concentration response functions; as such it 

does not meet the National Research Council recommendations (NRC, 2002). Similarly, the 

approach used by EPA does not meet the requirements of OMB (OMB Circular A-4, page 40-

41). For rules for which the costs are projected to exceed $1 billion annual threshold OMB 

requires a formal quantitative analysis of the relevant uncertainties including, if possible, 

probability distributions. 

EPA again used the same limited approach to assess uncertainty and did not provide a 

quantitative analysis of the key uncertainties that drive the very high benefits figures. Some of 

the key uncertainties that were not addressed include: 1) the quantitative impact of using other 

studies besides the outdated ACS Pope and Harvard Six Cities Laden to estimate PM mortality; 

2) the quantitative impact of using studies besides Bell and Levy to estimate ozone mortality.

Commenter: Mercatus Center at George Mason University

We find that the EPA has failed to acknowledge the high degree of uncertainty surrounding its 

estimates of benefits from this regulation. 

Additionally, there is a high degree of uncertainty, which the EPA itself acknowledges, 

surrounding the EPA’s benefits estimates. For example, the EPA describes criticisms related to 

its uncertainty analysis made by the National Resource Council in a 2002 report (1). Despite the 

EPA’s acknowledgement of these criticisms, the EPA continues to evaluate uncertainty in a 

similar manner (2). 

Our Response:
Chapter 8: Benefits

8-10

The EPA disagrees that it has not sufficiently quantified uncertainty in the Tier 3 benefits 

analysis. Our analysis contains a complex uncertainty characterization for the estimated benefits 

including a suite of quantitative and qualitative uncertainty analyses organized within a tiered 

uncertainty framework. The quantitative uncertainty analyses include Monte Carlo and 

probabilistic assessments, as well as sensitivity analyses using alternate assumptions. The EPA’s 

uncertainty analyses for benefits examine the effects of the most important methodological 

choices on results. For example, the EPA estimates mortality impacts using health effect 

estimates garnered from an EPA-sponsored expert elicitation,

21 which provide a range of effect 

estimates that span from smaller than the effect coefficient in the American Cancer Society 

cohort studies (Pope et al., 2002; Krewski et al, 2009)22,23 and larger than the effect coefficient in 

the Harvard Six Cities cohort studies (Laden et al., 2006; Lepeule et al., 2012).

24,25

Furthermore, we characterize ozone mortality using a range across six studies, not only 

the two cited by the commenter – three multi-city studies (Bell et al., 2004; Huang et al., 2005; 

Schwartz, 2005) and three meta-analyses (Bell et al., 2005; Ito et al., 2005; Levy et al., 

2005).26,27,28,29,30,31 This approach is consistent with recommendations provided by the National 

Research Council (NRC, 2008)32 and the studies were reviewed as part of the last ozone 

Integrated Science Assessment (ISA) prepared for the ozone NAAQS.33 

These approaches are fully consistent with Circular A-4 and EPA guidance.

 

21 Roman, Henry A., Katherine D. Walker, Tyra L. Walsh, Lisa Conner, Harvey M. Richmond, Bryan J. Hubbell, 

and Patrick L. Kinney. 2008. “Expert Judgment Assessment of the Mortality Impact of Changes in Ambient Fine 

Particulate Matter in the U.S.” Environ. Sci. Technol., 42(7):2268-2274.

22 Pope, C.A., III, R.T. Burnett, M.J. Thun, E.E. Calle, D. Krewski, K. Ito, and G.D. Thurston. 2002. “Lung Cancer, 

Cardiopulmonary Mortality, and Long-term Exposure to Fine Particulate Air Pollution.” Journal of the American 

Medical Association 287:1132-1141.

23 Krewski D, Jerrett M, Burnett RT, Ma R, Hughes E, Shi, Y, et al. 2009. “Extended follow-up and spatial analysis 

of the American Cancer Society study linking particulate air pollution and mortality.” HEI Research Report, 140, 

Health Effects Institute, Boston, MA.

24 Laden, F., J. Schwartz, F.E. Speizer, and D.W. Dockery. 2006. “Reduction in Fine Particulate Air Pollution and 

Mortality.” American Journal of Respiratory and Critical Care Medicine 173:667-672.

25 Lepeule J, Laden F, Dockery D, Schwartz J 2012. “Chronic Exposure to Fine Particles and Mortality: An 

Extended Follow-Up of the Harvard Six Cities Study from 1974 to 2009.” Environ Health Perspect. 

Jul;120(7):965-70.

26 Bell, M.L., et al. (2004). Ozone and short-term mortality in 95 U.S. urban communities, 1987-2000. JAMA, 

2004. 292(19): p. 2372-8. EPA-HQ-OAR-2009-0472-1662

27 Huang, Y.; Dominici, F.; Bell, M. L. (2005) Bayesian hierarchical distributed lag models for summer ozone 

exposure and cardio-respiratory mortality. Environmetrics. 16: 547-562. EPA-HQ-OAR-2009-0472-0233

28 Schwartz, J. (2005) How sensitive is the association between ozone and daily deaths to control for temperature? 

Am. J. Respir. Crit. Care Med. 171: 627-631. EPA-HQ-OAR-2009-0472-1678

29 Bell, M.L., F. Dominici, and J.M. Samet. (2005). A meta-analysis of time-series studies of ozone and mortality 

with comparison to the national morbidity, mortality, and air pollution study. Epidemiology. 16(4): p. 436-45. 

EPA-HQ-OAR-2009-0472-0222

30 Ito, K., S.F. De Leon, and M. Lippmann (2005). Associations between ozone and daily mortality: analysis and 

meta-analysis. Epidemiology. 16(4): p. 446-57. EPA-HQ-OAR-2009-0472-0231

31 Levy, J.I., S.M. Chemerynski, and J.A. Sarnat. (2005). Ozone exposure and mortality: an empiric bayes 

metaregression analysis. Epidemiology. 16(4): p. 458-68. EPA-HQ-OAR-2009-0472-0236

32 National Research Council (NRC). 2008. Estimating Mortality Risk Reduction and Economic Benefits from 

Controlling Ozone Air Pollution. National Academies Press. Washington, DC.

33 U.S. EPA. Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Final Report). U.S. 

Environmental Protection Agency, Washington, DC, EPA/600/R-10/076F, 2013.
Tier 3 Summary and Analysis of Comments

8-11

Since the publication of NRC (2002),34 the EPA has continued work to improve the 

characterization of uncertainty in both health incidence and benefits estimates. In response to 

these recommendations, the EPA expanded our previous analyses to incorporate additional 

quantitative and qualitative characterizations of uncertainty. While we have not yet been able to 

make as much progress towards the full, probabilistic uncertainty assessment envisioned by the 

NAS as we had hoped, we have added a number of additional quantitative and qualitative 

analyses to highlight the impact that uncertain assumptions may have on the benefits estimates. 

In addition, for some inputs into the benefits analysis, such as the air quality data, it is difficult to 

address uncertainty probabilistically due to the complexity of the underlying air quality models 

and emission inputs. In cases where there is insufficient scientific evidence to support alternative 

assumptions about key uncertain parameters, we provide qualitative assessments and do not 

simply speculate for the purposes of generating probabilistic uncertainty distributions.

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

EPA’s DRIA assumes implausible health benefits due to highly conservative, unrealistic 

assumptions. In the DRIA, the overwhelming majority of the benefits are derived from a very 

small calculated reduction of 0.05 μg/m3 in PM2.5 when the NAAQS standard is 12 μg/m3. 

EPA assumes with 100% certainty that exposure to any level of PM and ozone, whether far 

above or far below the current national standards, causes mortality. If EPA’s assumptions on 

mortality are not correct, and mortality does not occur at all or does not occur at lower levels, the 

benefits of the Tier 3 rule would be markedly reduced and the costs of the rule would exceed the 

benefits. API and AFPM detail our concerns in each of these areas, and point out the omission of 

key uncertainties that EPA failed to quantify. Using more realistic assumptions per existing 

references, the economic benefits of this proposed rule would be markedly lower than the costs 

in the proposed rule. As explained in detail in the comments, the flawed DRIA does not comply 

with OMB guidelines and should be withdrawn.

Over-estimated mortality attributed to small changes in PM2.5:

Similar to recent EPA air-related rules, most of the economic benefits of the proposed Tier 3 rule 

(well over 95%) accrue from preventing “premature mortality” attributed to small reductions in 

ambient PM2.5 and ozone. EPA assumes with 100% certainty that exposure to any level of PM 

and ozone, whether far above or far below the current national standards, causes mortality. If 

EPA’s assumptions on mortality are not correct, and mortality does not occur at all or does not 

occur at lower levels, the benefits of the Tier 3 rule would be markedly reduced and the costs of 

the rule would exceed the benefits. 

Nearly a decade ago, the National Research Council recommended that EPA discontinue using 

both the American Cancer Society (ACS) and Harvard Six Cities (H6C) cohorts for decision-

 

34 National Research Council (NRC). 2002. Estimating the Public Health Benefits of Proposed Air Pollution 

Regulations. Washington, DC: The National Academies Press. Washington, DC.
Chapter 8: Benefits

8-12

making (NRC, 2004). This recommendation was based on the concern for the age of the cohorts 

and fact that the individual and group factors used to adjust air pollution mortality risks were 

collected over 20 years ago and were never been updated. Today, the average ages of these 

cohorts is now 87 and the individual and group risk factors are over 30 years out of date. 

According to data provided by the Centers for Disease Control, cardiovascular mortality rates in 

the United States have been steadily decreasing (Kochanek et al. 2009; Danaei et al. 2009). In 

just one year, 2008 to 2009, the age-adjusted death rate for diseases of the heart decreased by 3.7 

% (Kochanek et al. 2009). The key factors responsible for this trend include reduction in 

smoking rates, various efforts to control blood pressure, and changes in diets (Danaei et al. 

2009). These factors for cardiovascular risk, called covariates in epidemiology studies, have 

changed markedly over the last three decades. For example, when the ACS and Harvard Six 

Cities cohorts were enrolled in the late 1970’s to early 1980’s, smoking rates were 33-37% 

(CDC, 2012). Today, these rates have fallen to under 20%. Various updates and reanalysis of the 

ACS and Harvard Six Cities studies inappropriately assume that the much higher rates were 

constant or proportional over the 30 years of study follow-up. 

Similarly, other key cardiovascular risk factors including control of high blood pressure and low 

density and total cholesterol, intake of salt and omega 3 fatty acids, have markedly changed over 

the last 30 years (Danaei et al. 2009). By not considering these national trends in well accepted 

risk factors for cardiovascular disease, the reduction in cardiovascular mortality that has been 

occurring in the U.S. has been inappropriately assigned by EPA to the coincident reduction in 

ambient PM2.5 in the U.S.

Despite the recommendations of the NRC and the well-known changes in risk factors responsible 

for the decline of cardiovascular mortality in the U.S., in the DRIA for the Tier 3 rule, EPA once 

again exclusively relied on studies using these two aged cohorts to estimate chronic mortality 

attributed to PM2.5 exposure. EPA ignored studies that used more modern cohorts or that 

reported a different spectrum of results (Greven et al., 2011; Krewski et al. 2000; Enstrom 2005; 

Beelen et al. 2008; Janes et al. 2007). EPA also ignored studies that reported a threshold for 

mortality (Abrahamowicz et al. 2003; Nicolich and Gamble 1999; Smith et al. 2000; Stylinaou 

and Nicolich 2009; Gamble and Nicolich 2006) and other studies that challenge EPA’s no 

threshold approach to risk assessment for PM (Koop and Tole 2006; Roberts and Martin 2006). 

In the draft DRIA, over two-thirds of the economic benefits are attributed to a small (0.05 

μg/m3) reduction in PM2.5 and most of these benefits are attributed to mortality. For the primary 

regulatory scenario that EPA presents in the DRIA, the number of PM mortalities estimated to be 

prevented ranged from 800 using Pope et al. (2002) to 2,100 using Laden et al. (2006). By 

comparison, the estimated ozone mortalities avoided were 170 to 770.

EPA used a single range of mortality coefficients (Pope to Laden) for PM2.5 and applied them 

across the U.S., even though significant regional heterogeneity has been reported in recent 

studies (Peng et al. 2005; Dominici et al. 2006, 2007; Enstrom 2005). In this manner, EPA does 

not address the issue that the benefits in various regions of the country differ widely. Since OMB 

guidelines encourage exploring regional variations in benefits (Circular A-4 page 8), EPA’s draft 

DRIA for the Tier 3 rule is deficient in this area. 
Tier 3 Summary and Analysis of Comments

8-13

Over 90% of the benefits result from reducing ambient levels of PM2.5 well below the NAAQS 

level [See Figure 12 on p. 39 of Docket number EPA-HQ-OAR-2011-0135-4276-A2]. Since a 

large fraction of the U.S. population lives in areas where the PM2.5 levels are well below EPA’s 

recently revised NAAQS, EPA assumes that ambient exposures even near background present an 

equal risk. EPA should not calculate mortality or other health benefits below the NAAQS for PM 

and ozone, levels.

If EPA set aside the economic benefits of the Tier 3 rule that are estimated below the NAAQS 

for PM and ozone, and ignored all of the other changes suggested here, the benefits of this rule 

would be markedly reduced (90% reduction) and would fall in the range of $0.8-2.3 billion. In 

this case, EPA’s estimated costs of the rule ($3.4 billion) would exceed the benefits by about 1.5-

4 fold. 

EPA again used the same limited approach to assess uncertainty and did not provide a 

quantitative analysis of the key uncertainties that drive the very high benefits figures. Some of 

the key uncertainties that were not addressed include: 4) the impact of extrapolating mortality 

and other health effects to far below levels deemed safe by EPA to near or below background/

EPA’s assumption that soluble sulfate and nitrate PM produce mortality with no threshold is 

inconsistent with published scientific information. Despite numerous attempts to encourage EPA 

to recognize that a long term epidemiology study has evaluated this key issue, EPA again 

ignored the study by Abrahamowicz et al. (2003) which reported no mortality at sulfate 

concentrations less than 12 μg/m3. This level is far above current ambient levels of sulfate PM in 

the U.S. Although soluble nitrate PM has not been evaluated in long term epidemiology studies, 

based on physical chemical properties, a similar result would be expected. Thus, the results of 

Abrahamowicz et al. suggest reducing secondary sulfate levels further by a fraction of 1 μg/m3 

as proposed in this rule will not result in any decrease in mortality. Therefore most of the 

mortality related benefits that EPA claims will result from this rule are not expected to occur. 

Commenter: Mercatus Center at George Mason University

A growing literature calls into question the causal link between the total concentration of 

ambient particulate matter and mortality levels, especially at the low doses that exist today in 

many parts of the United States. 

First, over 50 percent of the quantified benefits from the regulation are due to reductions in total 

particulate matter. However, a growing literature raises doubts about the causal link between 

ambient PM2.5 levels and increases in mortality. 

The EPA also acknowledges uncertainty with regards to its benefits analysis, including these 

points from table 8-16 of the Regulatory Impact Analysis for the rule: 

The extrapolation of effect estimates is beyond the range of ozone or PM concentrations 

observed in the source epidemiological study. 
Chapter 8: Benefits

8-14

Each point is important. First, the EPA states that its estimates go beyond those confirmed in the 

epidemiological study upon which it bases its findings. This means benefits of the regulation are 

based primarily upon model selection, not empirical evidence. The EPA assumes a linear-dose 

response down to the origin, resulting in large benefits estimates. Selecting another model, such 

as a threshold- or hormetic-dose response at low doses, would produce vastly lower benefits 

estimates. Recent academic literature has suggested there may be reason to believe PM exhibits a 

hormetic-dose response at low doses. 

Points 1...above imply that a benefits estimate of zero is within the realm of possibility for 

benefits resulting from reductions in particulate matter. Acknowledging this uncertainty should 

be a part of the Regulatory Impact Analysis (RIA). Elsewhere in the RIA, the EPA 

acknowledges that the “EPA estimated PM-related mortality without applying an assumed 

concentration threshold (section 8-9 of RIA).” Thus, the EPA assumes PM-related health 

benefits continue all the way down to very low levels. However, Cox has shown that there may 

be a hormetic-, or J-shaped-, dose-response curve for PM at low dose levels. If true, this implies 

there may be no negative health effects and potentially even health benefits to PM exposure at 

low-dose levels, rather than the harm the EPA assumes by model selection. Elsewhere, Cox has 

argued that the causal link between PM and human health benefits has not been adequately 

demonstrated at low doses. The EPA appears to be pointing to correlations without assessing 

whether causation is present. Fortunately, there are tests that can be done to demonstrate 

causation. The EPA would benefit from running these tests with the data available and 

presenting these results to the public. 

Additionally, Lutter and Fraas show that uncertainties surrounding benefits estimates from PM 

reductions may greatly exceed those that the EPA acknowledges in previous analyses for PMrelated rules. Lutter and Fraas give the EPA the benefit of the doubt and assume a causal 

relationship exists between PM and increases in mortality. They go on to demonstrate that 

benefits estimates vary greatly by modifying assumptions such as the value of reducing mortality 

risk or whether the toxicity is above or below the average for fine particles. 

Other experts in the field of environmental risk assessment have shown similar skepticism about 

the benefits of PM-related regulations. For example, the number of lives saved may be vastly 

overstated. 

The EPA’s methodology appears to be at odds with the very standards it applied to its own 

analyses prior to 2009. The EPA even acknowledges this methodological problem in point 1 

above. 

Our Response:

The EPA disagrees with the commenters regarding the evidence for health impacts at low 

concentrations, disagrees with the commenters’ recommendations regarding the assumptions and 

magnitude of benefits results that the EPA should apply in the RIA, and disagrees with the 

commenters’ erroneous interpretation of the NRC guidance with regard to the American Cancer 

Society (ACS) and Harvard Six Cities (H6C) studies. We also disagree that zero is within the 

realm of possibility for benefits resulting from reductions in particulate matter. The EPA’s 
Tier 3 Summary and Analysis of Comments

8-15

methods for quantifying health benefits of emission reductions are based on the best available 

peer-reviewed science and methods that have withstood scrutiny from EPA’s independent 

Science Advisory Board (SAB), the National Academy of Sciences (NRC, 2002), and 

continuous interagency review.

Regarding the NRC guidance, the citation provided is taken out of context. The NRC 

commented that the EPA should not rely on the Harvard Six Cities cohort and American Cancer 

Society cohort alone to the exclusion of a “new generation of cohort studies.” In formulating the 

decisions that informed the PM NAAQS (and also inform the Tier 3 analysis), the EPA 

considered all of the available scientific evidence, including studies of new cohorts. In addition, 

two separate panels of EPA’s independent Science Advisory Board (SAB) recently 

recommended that the EPA use these two cohorts to quantify PM2.5-related mortality risks and 

benefits (i.e., CASAC (2009, 2010) and Council (2010)).35,36,37 Despite some inherent 

limitations, these cohorts continue to have several advantages over other currently available 

cohorts, including age and gender representativeness, geographic representativeness, study size, 

consideration of confounders, and length of follow-up. EPA’s approach is consistent with the 

advice from NRC and SAB.

The EPA has also carefully considered the epidemiological, toxicological and clinical 

evidence linking exposure to fine particles and the onset of adverse health outcomes. When 

estimating PM-related risks, we rely upon studies and conclusions considered in the Integrated 

Science Assessment for Particulate Matter (PM ISA)(U.S. EPA, 2009) and the Provisional 

Assessment (U.S. EPA, 2012).38,39 These two comprehensive documents have assessed the entire 

body of scientific evidence regarding particles, including thousands of new studies (and include 

the studies mentioned by the commenter). The PM ISA received two rigorous rounds of peer 

review by the independent Clean Air Scientific Advisory Committee (CASAC) and concluded 

that the no-threshold model is best supported by the available data. Specifically, the PM ISA 

concluded that “[o]verall, the studies evaluated further support the use of a no-threshold log-

 

35 U.S. Environmental Protection Agency—Science Advisory Board (U.S. EPA-SAB). 2009. Review of Integrated 

Science Assessment for Particulate Matter (Second External Review Draft, July 2009). EPA-CASAC-10-001. 

November. Available on the Internet at 

<http://yosemite.epa.gov/sab/SABPRODUCT.NSF/81e39f4c09954fcb85256ead006be86e/151B1F83B02314558

5257678006836B9/$File/EPA-CASAC-10-001-unsigned.pdf>.

36 U.S. Environmental Protection Agency Science Advisory Board (U.S. EPA-SAB). 2010. CASAC Review of 

Quantitative Health Risk Assessment for Particulate Matter—Second External Review Draft (February 2010). 

EPA-CASAC-10-008. Available on the Internet at 

<http://yosemite.epa.gov/sab/sabproduct.nsf/264cb1227d55e02c85257402007446a4/BC4F6E77B638515585257

7070002F09F/$File/EPA-CASAC-10-008-unsigned.pdf>.

37 U.S. Environmental Protection Agency Science Advisory Board (U.S. EPA-SAB). 2010. Review of EPA’s 

DRAFT Health Benefits of the Second Section 812 Prospective Study of the Clean Air Act. EPA-COUNCIL-10-

001. June. Available on the Internet at 

<http://yosemite.epa.gov/sab/sabproduct.nsf/9288428b8eeea4c885257242006935a3/59e06b6c5ca66597852575e

7006c5d09!OpenDocument&TableRow=2.3#2.>.

38 U.S. Environmental Protection Agency (U.S. EPA). 2009. Integrated Science Assessment for Particulate Matter 

(Final Report). EPA-600-R-08-139F. National Center for Environmental Assessment—RTP Division. 

December. Available on the Internet at <http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=216546>.

39 U.S. Environmental Protection Agency (U.S. EPA). 2012. Provisional Assessment of Recent Studies on Health 

Effects of Particulate Matter Exposure. EPA/600/R-12/056A. National Center for Environmental Assessment—

RTP Division. December.
Chapter 8: Benefits

8-16

linear model.” In 2010, the Health Effects Subcommittee of the EPA’s independent Advisory 

Council on Clean Air Compliance Analysis (Council) “fully supports EPA’s decision to use a 

no-threshold model to estimate mortality reductions. This decision is supported by the data, 

which are quite consistent in showing effects down to the lowest measured levels. Analyses of 

cohorts using data from more recent years, during which time PM concentrations have fallen, 

continue to report strong associations with mortality. Therefore, there is no evidence to support a 

truncation of the CRF [concentration-response function].”

40 A summary of the scientific review 

statements regarding the lack of a threshold in the PM2.5-mortality relationship is documented in 

a technical support document.

41

Our approach to estimating PM-related health impacts below the lowest measured level 

(LML) is consistent with this advice. In general, we are more confident in the magnitude of the 

risks we estimate from simulated PM2.5 concentrations that coincide with the bulk of the 

observed PM concentrations in the epidemiological studies that form the basis of those 

estimates. Likewise, we are less confident in the risk we estimate from simulated PM2.5

concentrations that fall below the bulk of the observed data in these studies. For this reason, the 

EPA includes statistics in the final RIA showing the percentage of health impacts occurring 

above these levels for readers to understand the effect of this methodological decision. While 

this assessment provides some insight into the level of uncertainty in the estimated PM mortality 

benefits, EPA does not view the LML as a threshold and continues to quantify the PM-related 

mortality impacts using the full range of modeled air quality concentrations as the best estimate 

of the benefits.

We disagree with the comment that the RIA is deficient because the analysis does not 

address the issue that the benefits in various regions of the country differ widely, even though 

significant regional heterogeneity has been reported in recent studies. 

With respect to understanding the nature and magnitude of PM2.5-related risks, the EPA 

agrees that epidemiological studies evaluating health effects associated with long-term PM2.5

exposures have reported heterogeneity in responses between cities and effect estimates across 

geographic regions of the U.S. (U.S. EPA, 2009, sections 6.2.12.1, 6.3.8.1, 6.5.2, and 7.6.1; U.S. 

EPA, 2011, p. 2-25).42,43 However, the rationale that heterogeneity in risk estimates presents a 

potential bias as posed by the commenters is simplistic and does not account for a number of 

 

40 U.S. Environmental Protection Agency Science Advisory Board (U.S. EPA-SAB). 2010. Review of EPA’s 

DRAFT Health Benefits of the Second Section 812 Prospective Study of the Clean Air Act. EPA-COUNCIL-10-

001. June. Available on the Internet at 

<http://yosemite.epa.gov/sab/sabproduct.nsf/9288428b8eeea4c885257242006935a3/59e06b6c5ca66597852575e

7006c5d09!OpenDocument&TableRow=2.3#2.>.

41 U.S. Environmental Protection Agency (U.S. EPA). 2010. Technical Support Document: Summary of Expert 

Opinions on the Existence of a Threshold in the Concentration-Response Function for PM2.5-related Mortality. 

Research Triangle Park, NC. June. Available on the Internet at 

<www.epa.gov/ttn/ecas/regdata/Benefits/thresholdstsd.pdf>.

42 U.S. Environmental Protection Agency (U.S. EPA). 2009. Integrated Science Assessment for Particulate Matter 

(Final Report). EPA-600-R-08-139F. National Center for Environmental Assessment—RTP Division. 

December. Available on the Internet at <http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=216546>.

43 U.S. Environmental Protection Agency (U.S. EPA). 2011. Policy Assessment for the Review of the Particulate 

Matter National Ambient Air Quality Standards. EPA-452/D-11-003. April. Available on the Internet at 

<http://www.epa.gov/ttnnaaqs/standards/pm/s_pm_2007_pa.html>.
Tier 3 Summary and Analysis of Comments

8-17

factors that have been shown to influence city-specific risk estimates in epidemiologic studies. 

As discussed in the ISA, the EPA recognizes that there are compositional differences in PM2.5

across the country and that the county-level air quality data used in epidemiological studies may 

result in exposure error, which could in part account for variability in city-specific risk estimates 

(U.S. EPA, 2009, section 2.3.2).

Overall, the EPA recognizes that uncertainties still remain regarding various factors that 

contribute to heterogeneity observed in epidemiological studies. Nonetheless, the EPA 

recognizes that this heterogeneity could be attributed, at least in part, to differences in PM2.5

composition across the U.S., as well as to exposure differences that vary regionally such as 

personal activity patterns, microenvironmental characteristics, and the spatial variability of 

PM2.5 concentrations in urban areas (U.S. EPA, 2009, section 2.3.2; 77 FR 38910).

The current epidemiological evidence and the limited amount of city-specific speciated 

PM2.5 data does not allow conclusions to be drawn that specifically differentiate effects of PM in 

different locations (U.S. EPA, 2011, p. 2-25). Furthermore, the PM ISA concluded, “that many 

constituents of PM2.5 can be linked with multiple health effects, and the evidence is not yet 

sufficient to allow differentiation of those constituents or sources that are more closely related to 

specific health outcomes” (U.S. EPA, 2009, p. 2- 17). CASAC thoroughly reviewed the EPA’s 

presentation of the scientific evidence indicating heterogeneity in PM2.5 effect estimates in 

epidemiological studies and concurred with the overall conclusions presented in the ISA.

For all of the reasons listed above, the EPA believes that the approach used to estimate 

and present the human health benefits of the Tier 3 rule is appropriate and consistent with the 

currently accepted best practices for conducting national-level health impacts and benefits 

analyses. 

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Dismissed chemistry differences in PM toxicity potential:

Similar to EPA’s air-related rules, most of the chemistry of PM reduction from the Tier 3 rule is 

soluble secondary inorganic sulfate and nitrate PM that exhibits low toxicity potential in animal 

and human clinical studies (Schlesinger et. al. 2003; Amdur et al. 1998). By 2017, EPA 

estimated this rule will result in reduction of 284,381 tons of nitrogen oxides and 16,261 tons of 

sulfur oxides. EPA predicted much of these gaseous emissions will be converted to PM. By 

comparison, in the executive summary of the DRIA, EPA estimated the rule will produce a small 

(121 ton) reduction in directly emitted PM2.5 whereas in another section 7.1.3.2.2, EPA predicts 

the rule will produce an increase in directly emitted PM2.5. In either case, the rule will have little 

impact on ambient levels of directly emitted PM2.5 in the U.S. Thus, the large economic benefits 

EPA estimated for this rule are highly dependent on the assumption that soluble sulfate and 

nitrate PM exhibit the same remarkably high mortality producing potential as claims for PM2.5, 

the form of PM evaluated in the underlying health studies that EPA relied on. 
Chapter 8: Benefits

8-18

EPA again used the same limited approach to assess uncertainty and did not provide a 

quantitative analysis of the key uncertainties that drive the very high benefits figures. Some of 

the key uncertainties that were not addressed include: ... 3) the quantitative impact of varying 

particle chemistry on the PM mortality risk functions and benefits.

Commenter: Mercatus Center at George Mason University

The EPA also acknowledges uncertainty with regards to its benefits analysis, including these 

points from table 8-16 of the Regulatory Impact Analysis for the rule: 

Direct causal agents within the complex mixture of PM have not been identified. 

Next, the EPA fails to address whether the concentration of total particulate mass or the 

composition of those particulates are the cause of the health effects found in the cited studies. 

Moreover, because the composition of rural particulates is different from urban particulates, the 

health effects are likely to be different than those estimated. In order to provide a causal link, the 

EPA should be able to determine which components of particulate matter are the sources of the 

higher morbidity and mortality rates. For instance, Bell finds that higher concentrations of PM2.5 

Nickel are associated with higher rates of cardiovascular or respiratory hospitalizations. 

As Bell et al. conclude: Because of these limitations, health risks could be associated with the 

true concentrations of a component or set of components that co-varies with PM2.5 total mass, 

even if measured concentrations in this data set do not co-vary with PM2.5 total mass because of 

measurement error. Further, we did not investigate the possibility that observed PM2.5 health 

effects could result from a set of components with a collective concentration that co-varies with 

PM2.5 total mass, although individual component concentrations do not. 

Without a clear link between the chemical components of PM2.5 that are associated with health 

effects, the EPA is left to assume that the overall level of PM2.5 is the source of health risks, 

rather than particular components of the total PM2.5. If the health effects are due to a particular 

component, a more targeted, lower-cost, and potentially higher-benefit air pollution regulation 

might be warranted. The EPA does acknowledge that the causal connection between PM and 

human health outcomes is uncertain, as point 2 above demonstrates. 

Our Response:

While there remain uncertainties about the role and relative toxicity of various 

components of fine PM, the current evidence continues to support the view that fine particles 

should be addressed as a group for purposes of public health protection and that “many 

constituents of PM can be linked with differencing health effects and the evidence is not yet 

sufficient to allow differentiation of those constituents or sources that are more closely related to 

specific health outcomes” such that it is inappropriate to remove any constituent of PM2.5 from 
Tier 3 Summary and Analysis of Comments

8-19

the standard (U.S. EPA, 2009, 2-17; U.S. EPA, 2011, p. 2-25).44,45 EPA therefore disagrees that 

uncertainty in this assumption would eliminate almost all of the benefits associated with the Tier 

3 standards.

While most epidemiological studies continue to be indexed by PM2.5 mass, several recent 

epidemiological studies included in the ISA have used PM2.5 speciation data to evaluate health 

effects associated with fine particle exposures. In the ISA, the EPA thoroughly evaluated the 

scientific evidence that examined the effect of different PM2.5 components and sources on a 

variety of health outcomes (U.S. EPA, 2009, section 6.6) and observed that the available 

information continues to suggest that many different chemical components of fine particles and a 

variety of different types of source categories are all associated with, and probably contribute to, 

effects associated with PM2.5. The ISA concluded that the current body of scientific evidence 

indicated that “many constituents of PM can be linked with differing health effects and the 

evidence is not yet sufficient to allow differentiation of those constituents or sources that are 

more closely related to specific health outcomes” (U.S. EPA, 2009, p. 2-26 and 6-212). 

Furthermore, the ISA concluded that the evidence is not sufficient to support eliminating any 

component or group of components associated with any specific source categories from the mix 

of fine particles included in the PM2.5 indicator (U.S. EPA, 2009, p. 2-56). The Clean Air 

Science Advisory Committee (CASAC) agreed that it was reasonable to retain PM2.5 as an 

indicator for fine particles, as “[t]here was insufficient peer-reviewed literature to support any 

other indicator at this time” (p. 12).46

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Over-estimated mortality assumptions from small changes in ozone:

To estimate acute mortality attributed to ozone exposure, EPA used the study by Bell et al. 

(2004) and Levy et al. (2005) to characterize the low end and high end range, respectively, of the 

available literature. In this manner, EPA only used studies that reported a positive association 

between ozone and mortality. EPA excluded other studies that reported no clear association and 

confounding by particular matter (Smith et al. 2009, Franklin et al. 2007; Katsouyianni et al. 

2009). EPA also excluded epidemiology studies that report a threshold for ozone mortality 

(Stylianou et al. 2009) as well as other studies that conclude it is not possible to determine 

 

44 U.S. Environmental Protection Agency (U.S. EPA). 2009. Integrated Science Assessment for Particulate Matter 

(Final Report). EPA-600-R-08-139F. National Center for Environmental Assessment—RTP Division. 

December. Available on the Internet at <http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=216546>.

45 U.S. Environmental Protection Agency (U.S. EPA). 2011. Policy Assessment for the Review of the Particulate 

Matter National Ambient Air Quality Standards. EPA-452/D-11-003. April. Available on the Internet at 

<http://www.epa.gov/ttnnaaqs/standards/pm/s_pm_2007_pa.html>.

46 U.S. Environmental Protection Agency Science Advisory Board (U.S. EPA-SAB). 2010. CASAC Review of 

Quantitative Health Risk Assessment for Particulate Matter—Second External Review Draft (February 2010). 

EPA-CASAC-10-008. Available on the Internet at 

<http://yosemite.epa.gov/sab/sabproduct.nsf/264cb1227d55e02c85257402007446a4/BC4F6E77B638515585257

7070002F09F/$File/EPA-CASAC-10-008-unsigned.pdf>.
Chapter 8: Benefits

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whether or not thresholds exist at low ozone levels with observational data given the poor 

ambient to personal exposure correlation and high exposure misclassification (Brauer et al. 

2002). It is hard to understand how EPA could use anything other than zero for the low end.

Our Response:

The range of ozone benefits associated with the final Tier 3 rule is estimated based on 

risk reductions derived from several sources of ozone-related mortality effect estimates. This 

analysis presents six alternative estimates for the association based upon different functions 

reported in the scientific literature. We use three multi-city studies,47,48,49 including the Bell, 

2004 National Morbidity, Mortality, and Air Pollution Study (NMMAPS) that was used as the 

primary basis for the risk analysis in the ozone Staff Paper50 and reviewed by the Clean Air 

Science Advisory Committee (CASAC).51 We also use three studies that synthesize ozone 

mortality data across a large number of individual studies.52,53,54 This approach is consistent with 

recommendations provided by the NRC in their ozone mortality report (NRC, 2008),55 “The 

committee recommends that the greatest emphasis be placed on estimates from new systematic 

multicity analyses that use national databases of air pollution and mortality, such as in the 

NMMAPS, without excluding consideration of meta-analyses of previously published studies.” 

The NRC goes on to note that there are uncertainties within each study that are not fully captured 

by this range of estimates, but that analyses should “give little or no weight to the assumption 

that there is no causal association between estimated reductions in premature mortality and 

reduced ozone exposure.”

 

47 Bell, M.L., et al. (2004). Ozone and short-term mortality in 95 US urban communities, 1987-

2000. Jama, 2004. 292(19): p. 2372-8.

48 Huang, Y.; Dominici, F.; Bell, M. L. (2005) Bayesian hierarchical distributed lag models for 

summer ozone exposure and cardio-respiratory mortality. Environmetrics 16: 547-562.

49 Schwartz, J. (2005) How sensitive is the association between ozone and daily deaths to control 

for temperature? Am. J. Respir. Crit. Care Med. 171: 627-631.

50 U.S. EPA (2007) Review of the National Ambient Air Quality Standards for Ozone, Policy 

Assessment of Scientific and Technical Information. OAQPS Staff Paper.EPA-452/R-07-003. 

This document is available in Docket EPA-HQ-OAR-2003-0190. Retrieved on April 10, 

2009, from http:www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_sp.html

51 CASAC (2007). Clean Air Scientific Advisory Committee’s (CASAC) Review of the 

Agency’s Final Ozone Staff Paper. EPA-CASAC-07-002. March 26.

52 Bell, M.L., F. Dominici, and J.M. Samet. (2005). A meta-analysis of time-series studies of 

ozone and mortality with comparison to the national morbidity, mortality, and air pollution 

study. Epidemiology, 16(4): p. 436-45.

53 Ito, K., S.F. De Leon, and M. Lippmann. (2005). Associations between ozone and daily 

mortality: analysis and meta-analysis. Epidemiology. 16(4): p. 446-57.

54 Levy, J.I., S.M. Chemerynski, and J.A. Sarnat. (2005). Ozone exposure and mortality: an 

empiric bayes metaregression analysis. Epidemiology. 16(4): p. 458-68.

55 National Research Council (NRC), 2008. Estimating Mortality Risk Reduction and Economic 

Benefits from Controlling Ozone Air Pollution. The National Academies Press: Washington, 

D.C.
Tier 3 Summary and Analysis of Comments

8-21

The point raised by the commenters that the Smith et al. 2009, Franklin et al. 2007; and 

Katsouyianni et al. 2009 studies do not provide evidence of a clear association with ozone and 

mortality is incorrect. It is important to note that the scientific evidence available at the time of 

the 2008 Ozone NAAQS review forms the basis of this analysis. As such, these studies 

mentioned by the commenter were not considered in this analysis. However, these studies were 

thoroughly evaluated in the recently completed Ozone (O3) ISA, which will form the scientific 

basis of the ongoing O3 NAAQS review.56 Overall, these studies add to the growing body of 

scientific evidence for short-term O3 exposures and mortality and contributed to the ISA 

concluding that there is “likely to be causal relationship between short-term O3 exposures and 

mortality.” 

Finally, regarding the comment about thresholds, the conclusions in EPA’s recently 

completed ozone Integrated Science Assessment summarizes our position:

“Overall, the studies evaluated support a linear O3-mortality C-R relationship and 

continue to support the conclusions from the 2006 O3 Air Quality Criteria Document 

(AQCD), which stated that “if a population threshold level exists in O3 health effects, it is 

likely near the lower limit of ambient O3 concentrations in the United States” (U.S. EPA, 

2006).”57

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

EPA’s reliance on the meta analysis study by Levy et al. is not appropriate and significantly 

inflated the ozone mortality values. EPA’s use of this study is inconsistent with the conclusion 

the Agency reached in Integrated Science Assessment (ISA) for ozone. In the ISA, EPA 

recognized the risk estimates reported by Levy were biased high. Levy et al. only considered 

positive studies and there is inherent positive study publication bias in the time-series literature. 

Our Response:

It is unclear what the commenters are referring to because the Levy study was not reevaluated in the 2013 ISA.58 It is possible the commenters are referring to the 2006 Ozone Air 

 

56 U.S. EPA. Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Final Report). U.S. 

Environmental Protection Agency, Washington, DC, EPA/600/R-10/076F, 2013.

57 U.S. EPA. Air Quality Criteria for Ozone and Related Photochemical Oxidants (2006 Final). U.S. Environmental 

Protection Agency, Washington, DC, EPA/600/R-05/004aF-cF, 2006.

58 U.S. EPA. Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Final Report). U.S. 

Environmental Protection Agency, Washington, DC, EPA/600/R-10/076F, 2013.
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Quality Criteria Document (AQCD).59 In the AQCD, EPA never states that the Levy et al. results 

are biased high. In fact, we state they are consistent with the Bell and Ito meta-analyses:

“As stated earlier, the combined O3 excess mortality risk estimates from the metaanalyses by Bell et al. (2005), Ito et al. (2005), and Levy et al. (2005) were all very 

consistent. Although the analyses were conducted independently, there was considerable 

overlap among the risk estimates used in the three meta-analyses; thus, the agreement in 

the combined risk estimates was not unexpected... The positive O3 effect estimates, 

along with the sensitivity analyses in these three meta-analyses provide evidence of a 

robust association between ambient O3 and mortality. The combined effect estimates 

from the various meta-analyses ranged from 1.5 to 2.5% excess risk in all-cause mortality 

(p. 7-96 to 7-97; 2006 O3 AQCD).”

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

In the draft DRIA, EPA calculated U.S. wide ozone mortality using a single range of “national” 

risk coefficients (Bell to Levy) and applied this range across the United States. EPA excluded 

published studies that report clear regional heterogeneity in the ozone mortality association 

(Smith et al. 2009; Bell and Dominici 2008; Bell et al. 2007). In many regions of the U.S., no 

ozone mortality association is observed. Therefore, there is no valid national risk coefficient. In 

this manner, EPA avoided the issue that the benefits in various regions of the country will differ 

widely. Again, EPA’s approach did not conform to OMB guidelines that encourage exploring 

regional variation in benefits (OMB Circular A-4 page 8). 

Our Response:

The EPA recognizes that various individual- and community-level factors may influence 

regional heterogeneity (see p. 2-34 to 2-35 of the 2013 Ozone Integrated Science Assessment).60

We also recognize that there is currently no one currently agreed upon national risk coefficient to 

estimate ozone-related premature mortality. Instead, we present risk reductions derived from 

several sources of ozone-related mortality effect estimates, each with its own within-study 

probabilistic distribution of uncertainty. This approach is consistent with other measures of 

health impacts where multiple mortality effect estimates are available in the literature (e.g., PMrelated mortality risk). We therefore disagree that we did not conform to OMB guidelines when 

assessing the national-level health impacts associated with the Tier 3 rulemaking. 

Furthermore, the OMB A-4 guidelines cited by the commenter (pg. 8, “Different 

Requirements for Different Geographic Regions) are not applicable to the methods cited in the 

 

59 U.S. EPA. Air Quality Criteria for Ozone and Related Photochemical Oxidants (2006 Final). U.S. Environmental 

Protection Agency, Washington, DC, EPA/600/R-05/004aF-cF, 2006.

60 U.S. EPA. Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Final Report). U.S. 

Environmental Protection Agency, Washington, DC, EPA/600/R-10/076F, 2013.
Tier 3 Summary and Analysis of Comments

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comment. The guidelines cited by the commenter refer to alternative regulatory approaches (or 

the form of the standard), not to national-level health impact assessment methods. 

As mentioned earlier in this comments section, the range of ozone benefits associated with the 

final Tier 3 rule is estimated based on risk reductions derived from several sources of ozonerelated mortality effect estimates. This analysis presents six alternative estimates for the 

association based upon different functions reported in the scientific literature. We use three 

multi-city studies,61,62,63 including the Bell, 2004 National Morbidity, Mortality, and Air 

Pollution Study (NMMAPS) that was used as the primary basis for the risk analysis in the ozone 

Staff Paper64 and reviewed by the Clean Air Science Advisory Committee (CASAC).65 We also 

use three studies that synthesize ozone mortality data across a large number of individual 

studies.66,67,68 This approach is consistent with recommendations provided by the NRC in their 

ozone mortality report (NRC, 2008),69 “The committee recommends that the greatest emphasis 

be placed on estimates from new systematic multicity analyses that use national databases of air 

pollution and mortality, such as in the NMMAPS, without excluding consideration of metaanalyses of previously published studies.” The NRC goes on to note that there are uncertainties 

within each study that are not fully captured by this range of estimates, but that analyses should 

“give little or no weight to the assumption that there is no causal association between estimated 

reductions in premature mortality and reduced ozone exposure.”

At this time, as noted in the 2013 Ozone ISA (p. 2-35), “studies have not consistently 

identified specific community characteristics that explain the observed heterogeneity,” making it 

difficult to isolate and account for regional heterogeneity in a national-level rulemaking analysis. 

EPA continues to review the literature and will update our analyses as appropriate.

 

61 Bell, M.L., et al. (2004). Ozone and short-term mortality in 95 US urban communities, 1987-

2000. Jama, 2004. 292(19): p. 2372-8.

62 Huang, Y.; Dominici, F.; Bell, M. L. (2005) Bayesian hierarchical distributed lag models for 

summer ozone exposure and cardio-respiratory mortality. Environmetrics 16: 547-562.

63 Schwartz, J. (2005) How sensitive is the association between ozone and daily deaths to control 

for temperature? Am. J. Respir. Crit. Care Med. 171: 627-631.

64 U.S. EPA (2007) Review of the National Ambient Air Quality Standards for Ozone, Policy 

Assessment of Scientific and Technical Information. OAQPS Staff Paper.EPA-452/R-07-003. 

This document is available in Docket EPA-HQ-OAR-2003-0190. Retrieved on April 10, 

2009, from http:www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_sp.html

65 CASAC (2007). Clean Air Scientific Advisory Committee’s (CASAC) Review of the 

Agency’s Final Ozone Staff Paper. EPA-CASAC-07-002. March 26.

66 Bell, M.L., F. Dominici, and J.M. Samet. (2005). A meta-analysis of time-series studies of 

ozone and mortality with comparison to the national morbidity, mortality, and air pollution 

study. Epidemiology, 16(4): p. 436-45.

67 Ito, K., S.F. De Leon, and M. Lippmann. (2005). Associations between ozone and daily 

mortality: analysis and meta-analysis. Epidemiology. 16(4): p. 446-57.

68 Levy, J.I., S.M. Chemerynski, and J.A. Sarnat. (2005). Ozone exposure and mortality: an 

empiric bayes metaregression analysis. Epidemiology. 16(4): p. 458-68.

69 National Research Council (NRC), 2008. Estimating Mortality Risk Reduction and Economic 

Benefits from Controlling Ozone Air Pollution. The National Academies Press: Washington, 

D.C.
Chapter 8: Benefits

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What Commenters Said:

Commenter: Mercatus Center at George Mason University

Additionally, the EPA failed to consider other adverse effects of its rules, such as impacts on 

low-income individuals and adverse employment effects that were overlooked in the EPA’s scant 

employment impact analysis.

Finally, the EPA should go further to estimate unintended effects of its rules on employment and 

on low-income populations. 

Our Response:

As discussed in Preamble Section X.D and RIA Chapters 9.2.2 and 9.3.2, we expect the 

Tier 3 standards will have little effect on both the economy and jobs. Some commenters argue 

that the standards may increase, rather than decrease, employment (see Chapter 9.3 of this 

Response to Comments). In both the vehicle and the refinery sectors, reduced sales will tend to 

reduce employment, but the cost of the program is only about $72 per vehicle and less than a 

penny per gallon of gasoline. At the same time, the technologies required to comply with the 

standards will tend to contribute to increased employment, for example creating jobs at refineries 

and at high-tech companies developing and deploying emission control equipment for vehicles. 

EPA does not quantify most of the employment impacts of the standards and thus does not 

evaluate these countervailing impacts. However, because these two effects are likely to be small 

and counterbalance each other, we expect net employment impacts to be small.

Regarding impacts on low-income individuals, we note that the costs of these standards 

are estimated to be small – about $72 per vehicle, and less than one cent per gallon of gasoline.

Because low-income households rarely buy new vehicles, we expect the impacts of the vehicle 

standards on low-income households to be very small.

What Commenters Said:

Commenter: Chevron Products Company

There is more uncertainty around the non-economic components of the modeling used in the 

rule. This uncertainty stems from uncontrolled or poorly controlled confounding by co-pollutants 

and other risk factors when estimating an individual pollutant’s effect which likely overestimates 

the risk. Thus, in many studies, the data are likely compatible with a risk estimate of zero, 

particularly when reference is made to ozone mortality at ambient levels. 

Our Response:
Tier 3 Summary and Analysis of Comments

8-25

It is important to note for studies that examine the relationship between health effects and 

short-term air pollution exposures the only potential confounders are those variables that can also 

fluctuate on a day-to-day basis, such as other air pollutants, temporal trends, and weather. Within 

the 2006 O3 AQCD,70 specifically sections 7.1.3 and 7.6.4, the EPA thoroughly reviewed issues 

related to confounding and the evidence of potential confounding by copollutants. EPA 

recognizes that a major methodological issue affecting O3 epidemiologic studies concerns the 

evaluation of the extent to which other air pollutants may confound or modify O3-related effect 

estimates, and that the changing relationship between O3 and copollutants across seasons further 

complicates the issue. The use of multipollutant regression models is the prevailing approach for 

controlling potential confounding by copollutants in O3 health effects studies (2006 Criteria 

Document, p.7-24). In section 7.6.4.2, the 2006 Criteria Document reviews the evidence from 

studies that use multipollutant models to evaluate confounding by copollutants for effects 

ranging from mortality and respiratory hospitalizations to lung function measures and symptoms. 

EPA concluded in the 2006 Criteria Document that multipollutant regression analyses indicated 

that O3 risk estimates, in general, were not sensitive to the inclusion of copollutants, including 

PM2.5 and sulfate. As can be seen in Figure 1 below (Figure 7-22 from the 2006 Criteria 

Document) the O3 effect estimates for mortality are generally unchanged upon inclusion of PM 

in the models. These results suggest that the effect of O3 on respiratory health outcomes appears 

to be robust and independent of the effects of other copollutants (2006 Criteria Document, p.7-

154). Additionally, though the O3 effect was shown to be slightly diminished and did not retain 

statistical significance in multipollutant models with NO2, SO2 and PM10, there was considerable 

overlap in the 95% confidence intervals between the single-pollutant and multipollutant model 

results, leading EPA to conclude that the association was generally robust.

 

70 U.S. EPA. Air Quality Criteria for Ozone and Related Photochemical Oxidants (2006 Final). U.S. Environmental 

Protection Agency, Washington, DC, EPA/600/R-05/004aF-cF, 2006.
Chapter 8: Benefits

8-26

Attachment 2 - Associations between acute O3 exposure and mortality robust in multi-pollutant models including PM

Figure 7-22. All-cause (nonaccidental) O3 excess mortality risk 

estimates (95% CI) with adjustment for PM indices for all-year analyses per standardized increment. Analyses include all ages unless otherwise noted.

Figure 1. All-cause (nonaccidental) O3 excess mortality risk estimates (95% CI) with 

adjustment for PM indices for all-year analyses per standardized increment (see Section 

7.1.3.2, 2006 Criteria Document). Analyses include all ages unless otherwise noted.

Additional epidemiologic studies that examine the relationship between short-term O3

exposures and mortality, published since the completion of the 2006 O3 AQCD, were evaluated 

in the 2013 O3 Integrated Science Assessment (ISA) (Section 6.6.2.1).71 Unlike previous studies 

that were limited to primarily examining the confounding effects of PM10, the newer O3-

mortality studies expanded their analyses to include multiple PM indices (e.g., PM10, PM2.5, and 

 

71 U.S. EPA. Integrated Science Assessment of Ozone and Related Photochemical Oxidants (Final Report). U.S. 

Environmental Protection Agency, Washington, DC, EPA/600/R-10/076F, 2013.
Tier 3 Summary and Analysis of Comments

8-27

PM components). An examination of copollutant models reported evidence that associations 

between O3 and all-cause mortality were robust to the inclusion of PM10 or PM2.5 (Stafoggia et 

al., 2010; Katsouyanni et al., 2009; Bell et al., 2007),

72,73,74 while other studies reported evidence 

of a modest reduction (~20-30%) when examining PM10 (Smith et al., 2009).

75 An additional 

study that examined PM components, specifically sulfate, reported evidence for reductions in 

O3-mortality risk estimates in copollutant models (Franklin and Schwartz, 2008).

76 However, 

those studies that reported evidence of reductions in the O3-mortality associations had limited 

PM or PM component datasets as a result of the every-3rd- and 6th-day PM sampling schedule 

instituted in most cities, limiting the overall sample size employed to examine whether PM or 

one of its components confounds the O3-mortality relationship. Overall, the results from 

copollutant models in studies evaluated in the 2013 O3 ISA are consistent with and generally 

support the total body of epidemiologic evidence indicating that the O3-mortality risk estimates 

remain positive in copollutant models. 

In addition to examining copollutant confounding, the 2006 O3 AQCD evaluated 

sensitivity to model specification and concluded that O3 effect estimates “were generally 

more sensitive to alternative weather models than to varying degrees of freedom for 

temporal trend adjustment” (2006 Criteria Document, p.7-176). Model specification was 

further assessed in the 2013 O3 ISA, specifically for mortality, within the Air Pollution and 

Health: a European and North American Approach (APHENA) study. In APHENA the 

authors examined the influence of the extent of temporal smoothing on O3-mortality risk 

estimates. Katsouyanni et al. (2009) found that the extent of smoothing or the methods used 

for adjustment can influence O3 risk estimates when not applying enough degrees of 

freedom to control for temporal/season trends. This is because of the opposing seasonal 

trends between O3 and mortality. Overall, the results of the APHENA study are consistent 

with and support the conclusions of the 2006 O3 AQCD.

What Commenters Said:

Commenters: American Fuel & Petrochemical Manufacturers (AFPM), American Petroleum 

Institute (API), Marathon Petroleum Company LP (MPC), Chevron and Mercatus Center at 

George Mason University

 

72 Stafoggia, M; Forastiere, F; Faustini, A; Biggeri, A; Bisanti, L; Cadum, E; Cernigliaro, A; Mallone, S;

Pandolfi, P; Serinelli, M; Tessari, R; Vigotti, MA; Perucci, CA. (2010). Susceptibility factors to ozonerelated

mortality: A population-based case-crossover analysis. Am J Respir Crit Care Med 182: 376-384.

http://dx.doi.org/10.1164/rccm.200908-1269OC

73 Katsouyanni, K; Samet, JM; Anderson, HR; Atkinson, R; Le Tertre, A; Medina, S; Samoli, E; Touloumi, G;

Burnett, RT; Krewski, D; Ramsay, T; Dominici, F; Peng, RD; Schwartz, J; Zanobetti, A. (2009). Air

pollution and health: A European and North American approach (APHENA). (Research Report 142).

Boston, MA: Health Effects Institute. http://pubs.healtheffects.org/view.php?id=327

74 Bell, ML; Kim, JY; Dominici, F. (2007). Potential confounding of particulate matter on the short-term

association between ozone and mortality in multisite time-series studies. Environ Health Perspect 115:

1591-1595. http://dx.doi.org/10.1289/ehp.10108

75 Smith, RL; Xu, B; Switzer, P. (2009). Reassessing the relationship between ozone and short-term mortality in

U.S. urban communities. Inhal Toxicol 21: 37-61. http://dx.doi.org/10.1080/08958370903161612

76 Franklin, M; Schwartz, J. (2008). The impact of secondary particles on the association between ambient ozone

and mortality. Environ Health Perspect 116: 453-458. http://dx.doi.org/10.1289/ehp.10777
Chapter 8: Benefits

8-28

EPA Overstates Air Quality Benefits by Citing Benefits for Reducing Pollutants for Areas that 

are Already in Attainment:

Carbon Monoxide – In Table III-1 of the Tier 3 proposal, EPA projects CO reductions of 

746,683 tons in 2017 and 5,765,362 tons in 2030, but EPA does not even bother to discuss these 

benefits in the Tier 3 emissions reduction section. This is because EPA knows that nationwide 

CO emissions are averaging less than 25% of the CO NAAQS and have decreased 73% over the 

past 20 years. Reductions of pollutants below the established NAAQS safe levels do not count as 

benefits. All CO non-attainment areas are now in attainment and are now in maintenance mode. 

EPA needs to eliminate throughout this proposal all CO references that imply there are benefits 

from further CO as part of Tier 3, including its mention in Table III-1. 

Estimated Air Quality Benefits – The Clean Air Act requires EPA to set NAAQS at a level that 

protects public health with an adequate margin of safety. Therefore, there is no basis to look for 

or estimate possible effects below the level of the standard. The analysis should be a comparison 

of effects between the reference situation (i.e., no Tier 3) and the control situation (with Tier 3 in 

place) for counties not in attainment for a given standard at the onset of the Tier 3 program. 

EPA cites benefits for reducing pollutants for areas that are already in attainment—like reducing 

CO in a CO attainment area. Monetizing these reductions and attributing the economic benefit to 

Tier 3 is overstating the true value of the program. The Tier 3 program should not claim 

additional economic benefits for pollutant reductions when the base pollutant level is already in 

attainment with an existing standard. Only PM and ozone reductions are relevant for the 

proposed Tier 3 rule—all other criteria species are either attainment nationwide or attainment 

practically everywhere. 

We have identified several examples where we believe air quality benefits have been overstated:

- Ozone benefits are stated for counties that are already in attainment. Out of 676 nationwide 

counties modeled by EPA, only 11 non-California counties are forecast to exceed the 2008 ozone 

NAAQS in 2030 and therefore benefit from ozone precursor reductions. EPA included benefits 

for all counties modeled. 

- Similarly, annual Average Particulate Matter air quality levels are not significantly impacted by 

the Tier 3 rulemaking. Of 864 counties modeled, only 12 counties require PM2.5 precursor 

controls. By 2030, the Tier 3 rulemaking will actually increase PM2.5 levels in 10 nonattainment 

counties. This ‘disbenefit’ effect is due to reductions in reactive precursor species (like NOx) 

which can often result in increases in the secondary pollutants ozone and PM. 

- Carbon monoxide reductions in emissions are not needed since all counties experience healthy 

air concentration levels--monetized benefits attributed to CO reductions are therefore 

inappropriate, except perhaps as an ozone or PM precursor. 

- Mobile Source Air Toxics reductions are appropriately described but EPA is precluded by the 

Clean Air Scientific Advisory Committee from using current tools to monetize or justify benefits 

because human health data and ambient measurements are not credible. Therefore, MSAT 

emissions reductions can be acknowledged but not as a quantifiable benefit. 

Based on these observations, we conclude that EPA has overstated the monetary value of the 

Tier 3 air quality benefits. 
Tier 3 Summary and Analysis of Comments

8-29

It is also odd that the EPA would seek to reduce PM levels beyond those the EPA just finalized 

in new NAAQS standards for PM in January. If there are so many unclaimed benefits from 

reducing PM, why not make the NAAQS standards even lower when the EPA had the chance? 

Our Response: 

EPA does not agree that it has overstated the monetary value of the Tier 3 air quality 

benefits. Chapter 8 of the RIA describes the methodology for quantifying and monetizing 

benefits. The quantified benefits associated with this rule are based on reductions in emissions, 

for the entire contiguous United States, that affect ambient concentrations of ozone and PM2.5. 

EPA does not quantify or monetize health benefits associated with CO or mobile source air 

toxics. To be consistent and transparent in its assessment of Tier 3 impacts, EPA presents 

changes in emissions and ambient concentrations for all criteria pollutants (including CO) and 

some mobile source air toxics. EPA also presents changes in all modeled ozone and PM2.5 

design values due to the Tier 3 standards. Design values are projected only for counties with 

monitored data available. 

EPA disagrees with the statement that “reductions of pollutants below the established 

NAAQS safe levels do not count as benefits.” The NAAQS are not set at levels that eliminate 

the risk from air pollution. Instead, EPA sets the NAAQS at a level requisite to protect public 

health with an adequate margin of safety, taking into consideration effects on susceptible 

populations found in the scientific literature. For instance, the risk analysis prepared in support of 

the PM NAAQS reported risks below these levels, while acknowledging that the confidence in 

those effect estimates is higher at levels closer to the standard (U.S. EPA, 2010).77 Furthermore, 

both the PM and Ozone Integrated Science Assessments (U.S. EPA, 2009 and U.S. EPA, 

2013)78,79 have determined that there is no evidence of a population-level threshold (i.e., a level 

below which there is no risk for adverse health effects) in PM- and ozone-related health effects 

in the epidemiological literature. While estimates of PM- and ozone-related health impacts that 

occur below the standards are more uncertain than those occurring above the standards, the EPA 

considers these to be legitimate components of measures of criteria pollutant health risk.

EPA also states in Section II of the preamble that as of September 27, 2010 all CO 

nonattainment areas were redesignated to maintenance areas.

What Commenters Said:

 

77 U.S. Environmental Protection Agency (U.S. EPA). 2010. Quantitative Health Risk Assessment for Particulate 

Matter—Final Report. EPA-452/R-10-005. Office of Air Quality Planning and Standards, Research Triangle 

Park, NC. September. Available on the Internet at 

<http://www.epa.gov/ttnnaaqs/standards/pm/data/PM_RA_FINAL_June_2010.pdf>.

78 U.S. Environmental Protection Agency (U.S. EPA). 2009. Integrated Science Assessment for Particulate Matter 

(Final Report). EPA-600-R-08-139F. National Center for Environmental Assessment—RTP Division. 

December. Available on the Internet at <http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=216546>.

79 U.S. Environmental Protection Agency (U.S. EPA). 2013. Integrated Science Assessment for Ozone and Related 

Photochemical Oxidants (Final Report). EPA 600/R-10/076F. National Center for Environmental Assessment—

RTP Division. December. Available on the Internet at 

<http://cfpub.epa.gov/ncea/isa/recordisplay.cfm?deid=247492>.
Chapter 8: Benefits

8-30

Commenter: Chevron Products Company

As noted by Environ in their assessment of the impacts of nationwide adoption of the LEV III 

program and a 10 ppm sulfur standard, (1) the Tier 2 program is estimated to result in substantial 

emission reductions. In 2022, Environ estimated that the Tier 2 program would result in a 66% 

reduction in NOx (11,342 Mg/day) and a 55% reduction in VOC (3787 Mg/day) for the on-road 

motor vehicle fleet relative to the Tier 1 program. On the other hand, the LEV III/10 ppm S 

controls (similar to EPA’s Tier 3 proposal) would result in a 6% reduction from both NOx (628 

Mg/day) and VOC (179 Mg/day)relative to Tier 2 in 2022 (greater reductions would accrue as 

the vehicle standards are fully implemented). EPA should also report the benefits attributable to 

the Tier 2 program to allow an assessment of the incremental benefits of the Tier 3 proposal 

relative to the Tier 2 program. 

It is not clear exactly how EPA estimated the health and economic benefits. Without a better 

understanding, it is difficult to understand how the extremely modest estimated impact of the 

Tier 3 programs had on pollutant levels by 2030 translated into the EPA reported health and 

economic benefits. For example, Chapter 7.2.4 of the draft RIA estimates that, in 2030, Tier 3 

will result in a reduction of the weighted annual average values for ozone and PM2.5 that are 

each less than l percent of the current annual standards. 

Our Response: 

The benefits presented in the RIA are based on the incremental reduction in PM- and 

ozone-related pollutant emissions related to the final Tier 3 standards compared to a world 

without the Tier 3 standards in place. This baseline, or reference case, includes all finalized 

regulations at the time of the analysis. The baseline therefore includes Tier 2 emission controls; 

the benefits of the Tier 3 rule are incremental to those related to the Tier 2 rule. We refer the 

commenter to the Tier 2 RIA for information about the estimated impacts of that rulemaking 

(http://www.epa.gov/tier2/).

Chapter 8 of the RIA describes the methodology involved in quantifying and monetizing 

the benefits of the Tier 3 rule. We base our analysis of the program’s impact on human health 

and the environment on peer-reviewed studies of air quality and human health effects.80,81,82 Our 

benefits methods are consistent with the Regulatory Impact Analyses (RIAs) that accompanied 

the final revisions to the National Ambient Air Quality Standards (NAAQS) for Particulate 

Matter, the 2008 final ozone NAAQS, and the 2010 ozone NAAQS reconsideration.

 

80 U.S. Environmental Protection Agency. (2012). Regulatory Impact Analysis for the Final Revisions to the 

National Ambient Air Quality Standards for Particulate Matter. Prepared by: Office of Air and Radiation, EPA452/R-12-005. Retrieved November 22, 2013 at http://www.epa.gov/ttn/ecas/ria.html

81 U.S. Environmental Protection Agency. (2008). Final Ozone NAAQS Regulatory Impact Analysis. Prepared by: 

Office of Air and Radiation, Office of Air Quality Planning and Standards. Retrieved November 22, 2013 at 

http://www.epa.gov/ttn/ecas/ria.html. EPA-HQ-OAR-2009-0472-0238

82 U.S. Environmental Protection Agency. (2010). Summary of the updated Regulatory Impact Analysis (RIA) for 

the Reconsideration of the 2008 Ozone National Ambient Air Quality Standard (NAAQS). Prepared by: Office 

of Air and Radiation, Office of Air Quality Plannin and Standards. Retrieved November 22, 2013 at 

http://www.epa.gov/ttnecas1/regdata/RIAs/s1-supplemental_analysis_full.pdf.
Tier 3 Summary and Analysis of Comments

8-31

What Commenters Said:

Commenter: Private Citizen

It is my belief that the supposed cost savings in health costs will never materialize as suggested 

by proponents of the bill. What we do know from past experience is that 1) the government 

always under estimates the cost of everything they foist upon the public 2) that the performance 

of light and medium vehicles will diminish 3) the cost to implement and comply with these 

regulations will be much greater than proposed 4) this is but another attack on the free enterprise 

system. Those in favor of this regulation point out that a large number of people in this country 

have asthma and apparently it is caused by the exhaust from automobiles. Is that true? If 

automobile exhaust is the cause of asthma why doesn’t everyone suffer from asthma? If this 

regulation is implemented how many asthma suffers will be cured? How many will be prevented 

from becoming asthmatics? I see this as another unneeded intrusion by government into the free 

enterprise system.

Our Response:

Chapter 7 of the RIA that accompanies this rulemaking describes the methods and 

assumptions that inform our cost analysis. Our cost estimates reflect the most up-to-date and 

scientifically sound data available, and we believe our estimates are therefore accurate 

predictions of future costs associated with the final Tier 3 rulemaking. Furthermore, as presented 

in Chapter 8 of the RIA, the final Tier 3 rulemaking will provide the public with very significant 

health benefits that clearly outweigh the costs. For the final rulemaking, we estimate that by 

2030, the annual emission reductions of the Tier 3 standards will annually prevent between 660 

and 1,500 PM-related premature deaths, between 110 and 500 ozone-related premature deaths, 

2,200 hospital admissions and asthma-related emergency room visits, 19,000 asthma 

exacerbations, 30,000 upper and lower respiratory symptoms in children, and 1.3 million lost 

school days, work days, and minor restricted activity days.

Asthma prevalence in the United States is widespread and well-documented, but there is 

currently no cure for asthma. Asthma symptoms can be triggered by a number of different 

causes, including air pollution emitted from vehicles. The health impact assessment (HIA) in the 

Tier 3 RIA quantifies the changes in the incidence of adverse health impacts resulting from 

changes in human exposure to both PM2.5 and ozone air quality. HIAs are a well-established 

approach for estimating the change in adverse health impacts expected to result from populationlevel changes in exposure to pollutants. They rely on the published scientific literature to 

ascertain the relationship between PM2.5, ozone, and adverse human health effects. For asthmarelated endpoints included in this analysis, we estimate the number of exacerbated asthma attacks 

and the number of asthma-related emergency room visits that will be avoided as a result of the 

PM2.5 and ozone reductions associated with the final Tier 3 rulemaking. Please refer to Chapter 

8 of the RIA for more information.
Tier 3 Summary and Analysis of Comments

9-1

9 Economic Impact Analysis

What We Proposed:

The comments in this chapter correspond to Section X of the preamble to the proposed 

rule and address the economic impacts of the program. A summary of the comments received 

and our response to those comments are located below.

What Commenters Said:

Commenter: BlueGreen Alliance

The Tier 3 standard will only bolster the auto industry's ability to meet a strong fuel efficiency 

standard and generate these net positive economic outcomes. Implementation of Tier 3 will 

also have a positive economic impact in other sectors as well.

Additionally, the program includes critical elements that will allow refiners to deliver 

cleaner fuels to the market in an economical and timely manner, as well as provisions that 

ensure smaller manufacturers and refiners can reach compliance without unfair burden. It is 

critical to provide a mechanism like this to help industries transition to a cleaner regulatory 

framework. For example, the advanced technology vehicle manufacturing loan program has 

created or sustained more than 40,000 jobs in the auto sector advancing fuel saving 

technologies.

As we have seen in the automobile and other industries, investment in pollution reduction 

technologies leads to gains in efficiency and job creation.

Commenter: Boulder County Board of Commissioners and Boulder County Board of Health

Boulder County applauds the EPA for proposing the Tier 3 package and reiterates its strong 

support for this program because it will directly benefit the air quality in our community and 

across the nation. These are substantial, cost-effective emission reductions from proven 

technologies that will create jobs and improve public health and the environment. 

Commenter: Business for Innovative Climate and Energy Policy (BICEP)

In sum, the proposed Tier 3 standards represent a unique opportunity for the United States to 

strengthen the economy and create jobs, as well as prevent illness and reduce healthcare 

expenditures. 

Commenter: California Air Resources Board (CARB)

CARB staff supports the approach used to evaluate the economic impacts of U.S. EPA's Tier 3 

proposal. 
Chapter 9: Economic Impact Analysis

9-2

Due to the differences in regulatory scope, timeframes, and geography, a direct comparison to 

CARB's LEV III economic impact analysis is incompatible. However, given that the proposal's 

compliance costs and cost-effectiveness metrics are on the same order of magnitude as those 

estimated by CARB in previous related rulemakings, CARB staff concurs with U.S. EPA's 

overall conclusions on the direction and magnitude of economic impacts to the auto and 

refinery sectors. However, some time has passed since the initial evaluation of technology costs 

detailed in the draft Regulatory Impact Analysis. Therefore, it may be appropriate for U.S. EPA 

to revisit those costs estimates to determine if any revisions are warranted. 

Commenter: Ceres Investor Network on Climate Risk

Furthermore, Tier 3 will result in net economic gains and job growth, and help ensure the 

United States’ leadership position in vehicle and emission control technology. As widely 

diversified investors with exposure across virtually all industries, sectors and markets the 

performance of member portfolios is linked in no small part to overall economic performance. 

Consequently, we believe the economic benefits described in this letter will also be beneficial 

to the performance of our investments. 

Further, Tier 3 also presents an opportunity to ensure the United States continues to be a 

globally competitive leader in the auto and emission control industries. The standards will send 

a clear regulatory signal to suppliers and manufacturers, encouraging technological innovation 

and investment. 

Commenter: Emissions Control Technology Association (ECTA)

ECTA has long supported the adoption of emission control standards reflected in EPA’s Tier 3 

proposal, but opponents have continuously tried to undermine Tier 3 by making claims that it 

would have negative economic consequences. It has been claimed that the sulfur content 

requirement of Tier 3 will dramatically increase the cost of refining gasoline, increase the price 

of gasoline at the pump, cause job loss, and reduce economic activity. To address these 

criticisms, ECTA engaged Navigant Economics [See Docket number EPA-HQ-OAR-2011-

0135-4293-A2] to evaluate the economic impact of the pending rule (1). The study concluded 

that the pending rule would increase the average cost of refining by about one cent per gallon, 

in all likelihood not affect gasoline prices, increase employment, and generate economic 

activity. A copy of the study is attached with this comment.

The rule had not been published when this study was completed in June, 2012. But, it was well 

known in June, 2012 that the substance of the proposal would be similar to LEV III, which was 

adopted by California in 2012.

Commenter: Kentucky Division for Air Quality

EPA’s documents state that the increase in gas and Vehicle prices would cause an initial 

decrease in the sales of gas and vehicles. Historically, the reduced travel was determined to be 

negligible; therefore, it would have little impact. It is also for this reason, we do not see EPA’s 

Tier 3 proposed rule affecting KYTC in an adverse way.
Tier 3 Summary and Analysis of Comments

9-3

Commenter: Manufacturers of Emission Controls Association (MECA)

EPA’s proposed Tier 3 emissions and fuel standards will provide additional support for the 

continued development of a thriving U.S. industry focused on a wide range of technologies that 

can reduce vehicle criteria emissions. 

Commenter: Motor & Equipment Manufacturers Association (MEMA)

As the process moves forward, the EPA must maintain regulatory clarity and a coherent 

national pathway that affords the vehicle manufacturers and vehicle parts suppliers with critical 

planning and investment certainty. MEMA recognizes the need for appropriate, sensible 

regulation. On the other hand, regulations should not place an undue burden on free enterprise, 

should not be arbitrary and capricious in their requirements or implementation, and should not 

hinder the global competitiveness of the industry. Rather, the regulations should be based on 

sound science and data and balance the public interest objectives with economic realities of 

manufacturers. The effectiveness of the proposed regulations are projected figures and should 

be periodically evaluated and reviewed with recorded, real-world data to see if the cost/benefit 

projections are being realized. 

Commenter: PennFuture

In addition, Tier 3 will drive the advances in emissions control technology developed here in 

the U.S. and exported globally.

Commenter: United Steelworkers Union (USW)

The USW has a diverse membership that will, in several cases, benefit from the proposed rule. 

For example, USW members employed at Corning Inc. who produce advanced catalytic 

converters will see the benefits of high tech jobs building pollution-reducing vehicle 

components. 

Commenter: Wespath Investment Management

Wespath has reviewed positions on both sides of Tier 3, and has considered the potential longterm financial implications to our investments, which is material to fulfill our promises to our 

stakeholders. In our view, Tier 3 standards will be beneficial to several sectors where we hold 

investments, including the auto manufacturers, auto parts manufacturers, trucking companies, 

health care providers, and health insurance companies. We also invest in many oil refining 

companies, which have expressed concern over the impact of Tier 3 on their operations. 

Overall, we believe the potential for negative impact in the oil sector is limited, and outweighed 

by the collective benefit to other sectors. 

Job creation: The fact that a wide range of stakeholders have spoken in favor of the proposed 

standards speaks to the broad economic benefits. The standards are supported by trade 

associations such as the Alliance of Automobile Manufacturers, Global Automakers, the 
Chapter 9: Economic Impact Analysis

9-4

American Trucking Association, and the Manufacturers of Emission Controls Association. 

Public companies whose shares we hold that have also made supportive statements include 

General Motors, Honda, Toyota, Daimler Chrysler, Ford, Donaldson Company, Tenneco, 

BorgWarner, and Corning. These companies believe that the standards are in their long-term 

best interests and will promote their future growth, and we agree. 

Many companies have told us that without clear policy signals from Washington, innovation 

stalls and capital sits on the sidelines. Setting strong standards will be the signal companies are 

looking for to begin production that incorporates new technologies. This will ripple throughout 

the supply chain, allowing manufacturers to bring new and more efficient products to market. 

Further, many in the industry have said that the Tier 3 standards are necessary to enable auto 

companies to meet the new fuel economy and greenhouse gas standards, which will spur 

innovation and growth in the auto industry.

Our Response:

Some of these comments express support for the Tier 3 standards based on the positive 

impacts and innovation that these standards will spur; others provide statements of caution 

about the tradeoffs between “public interest objectives [and] economic realities of 

manufacturers.” Some comments suggest that the standards will increase economic activity 

and employment, while others suggest that the effects will be small. Chapters 9.1, 9.2, and 9.3

below provide more detailed responses related to the impacts on vehicle sales, oil production, 

and employment. As discussed in Section X. of the Preamble and Chapter 9 of the RIA, EPA 

has concluded that the effects of the standards on sales in both the auto and refinery sectors are 

likely to be small, because the cost impacts to consumers are expected to be small. These small 

impacts imply small effects on employment as well.

We agree, as several commenters note, that the standards are likely to encourage firms 

to innovate in order to find less expensive ways to achieve the standards. The certainty 

provided by the standards is expected to encourage investment both to achieve the standards 

and to find less expensive ways to meet them.

We agree with MEMA that “the regulations should be based on sound science and data 

and balance the public interest objectives with economic realities of manufacturers.” The 

Preamble and RIA provide our full discussion of these tradeoffs. RIA Chapter 8.1.3 provides a 

comparison of the benefits and costs, and finds that the benefits in 2030 (the year in which air 

quality benefits are monetized) are expected to outweigh the costs: for a 3% discount rate, 

benefits less costs are estimated to be $5.9-$18 billion; for a 7% discount rate, benefits less 

costs are estimated to be $5.2-$17 billion. EPA follows trends in the auto and fuels industries 

relating to costs, and it monitors compliance with the standards and the impacts on air quality. 

9.1. Vehicle Sales Impacts

What Commenters Said:
Tier 3 Summary and Analysis of Comments

9-5

Commenter: Attorney General of Connecticut, et.al

The Tier 3 standards would also benefit our economy. Automakers strongly support the 

standards, which would enable them to sell vehicles meeting California’s Low Emission

Vehicle III standards in all 50 states and at the same time achieve EPA greenhouse gas 

emission standards for the model years 2017-25. 

Commenter: Attorney General of New York, et.al:

The Tier 3 standards would also benefit our economy. Automakers strongly support the 

standards, which would enable them to sell vehicles meeting California’s Low Emission 

Vehicle III standards in all 50 states and at the same time achieve EPA greenhouse gas 

emission standards for the model years 2017-25. 

Commenter: Consumers Union

New car buyers will also benefit. Starting in 2017, new cars will have tighter limits on tailpipe 

emissions, including carbon monoxide and benzene, which can linger in garages and even 

attached residential living space (4). The proposed rule also offers automakers an incentive to 

go beyond the minimum 8-year/ 80,000-mile warranty currently required for emissions control 

systems, and extend it to 15-years/150,000 miles for new vehicles. This move could improve 

reliability and lower costs to maintain emissions control systems.

Low sulfur gasoline also enables auto makers to develop a greater array of technology, such as 

lean burn, to meet emissions and fuel economy standards more creatively and at a lower cost.

4 - International Journal of Ventilation Volume 2 No 3 , “Air and Pollutant Transport from Attached 

Garages to Residential Living Spaces – Literature Review and Field Tests,“, National Institute of 

Standards and Technology, available at: http://fire.nist.gov/bfrlpubs/build03/PDF/b03067.pdf.

Commenter: Manufacturers of Emission Controls Association (MECA)

MECA agrees with EPA staff’s assessment that achieving the proposed Tier 3 exhaust and 

evaporative emission standards and associated emission reductions are both technically feasible and 

cost-effective. This fact is clearly demonstrated by the more than two million SULEV- and 

PZEV-compliant light-duty vehicles that have been sold in the U.S. market since these nearzero emission, gasoline vehicles were first introduced more than ten years ago.

Commenter: Consumers Union

New car buyers will also benefit. Starting in 2017, new cars will have tighter limits on tailpipe 

emissions, including carbon monoxide and benzene, which can linger in garages and even 

attached residential living space.

4

The proposed rule also offers automakers an incentive to go 

beyond the minimum 8-year/ 80,000-mile warranty currently required for emissions control 

systems, and extend it to 15-years/150,000 miles for new vehicles. This move could improve 

reliability and lower costs to maintain emissions control systems. 
Chapter 9: Economic Impact Analysis

9-6

4

International Journal of Ventilation Volume 2 No 3 , “Air and Pollutant Transport from Attached 

Garages to Residential Living Spaces – Literature Review and Field Tests,“, National Institute of 

Standards and Technology, available at: http://fire.nist.gov/bfrlpubs/build03/PDF/b03067.pdf.

Commenter: U.S. Coalition for Advanced Diesel Cars

The standards will also encourage the development of innovative new technologies and provide 

American consumers with more and cleaner vehicle choices.

Our Response:

These comments express support for the standards based on their impacts on vehicle 

sales and innovation. The auto industry is expected to take advantage of having one set of 

standards for the U.S.; this program contributes to that goal. We agree with MECA that the 

new standards are feasible. We agree as well that new vehicle owners as well as the general 

public will benefit from reduced tailpipe and evaporative emissions. And, as discussed in the 

introductory part of Chapter 9 (above) of this S&A, we agree that the standards will encourage 

innovation in technologies.

9.2. Impacts on Petroleum Industry

What Commenters Said:

Commenter: Clean Air Watch

I'll just note that they're wrong. You're going to hear today, I believe, from Navigant, who's 

going to critique some of the oil industry's current cost projections on this study, so I will hope 

that you'll listen carefully and then leave it to them. But I'd like to look at some of the past 

examples of what I would call crying wolf by the oil industry. Let's consider a few examples 

where they've been wrong.

When EPA proposed a phase out of lead in gasoline in the 1970s, the oil industry claimed there 

was no public health advantage to be gained, and that this would cause supply shortages. Not 

only was this sky is falling prediction dead wrong, we know now it was one of the best steps 

for public health ever made by the EPA. Taking lead out of gas reduced the risk of lead 

toxicity for hundreds of thousands of children. It also decreased the risk of heart attack and 

stroke. Oh, and we didn't have those supply shortages.

In 1999, when EPA proposed the so-called Tier 2 standards in allied sulfur and gas reductions, 

once again the oil industry claimed that clean up wasn't needed, and it would cause shut downs 

and supply shortages. In fact, in this case they even said it would threaten national security.

Well, of course these problems didn't happen either. It was sheer nonsense.

Let's take a third example. In the year 2000 after EPA proposed clean diesel fuel standards, the 

oil industry again claimed – now, can you guess – that the cleanup wasn't needed, and it was 

cause refinery shutdowns and supply shortages. Guess what? The exact opposite happened.

The U.S. now exports clean diesel fuel because EPA stuck to its guns.
Tier 3 Summary and Analysis of Comments

9-7

So I would just like to say let's learn from the past. This is not the United States of Amnesia, I 

hope. Let's remember the oil industry has cried wolf so many times in the past, always been 

wrong. It's doing it again here. Let's consider the massive health benefits of this plan that a lot 

of other witnesses have already talked about. We know that they dwarf the very modest costs.

Commenter: Emissions Control Technology Association (ECTA)

Tier 3 is Unlikely to Increase Retail Gasoline Prices. We disagree with EPA’s conclusion that 

the proposed rule would increase the cost of gasoline to consumers. 

EPA concludes that:

“We do not estimate the price increase that consumers are likely to face, though we note that it 

should be positive and up to the increase in manufacturer’s cost of gasoline production” (2). 

This conclusion is drawn from: (1) the observation that in a perfectly competitive industry the 

increased cost of refining would be passed along to consumers; and (2) the assumption, based 

upon a report published by the Federal Trade Commission, that the refining industry is 

relatively competitive (3). 

While we do not comment on the competitiveness of the U.S. refining industry, we believe that 

the proposed rule is unlikely to result in an increase in the price of gasoline to consumers. We 

draw this conclusion from an empirical analysis previously prepared by Navigant Economics 

(4), which examined the effect of EPA sulfur content regulation on the monthly average price 

of gasoline during the period from January 2001 to January 2012. 

This statistical evidence leads one to conclude that, in all probability, the sulfur-content 

regulation of Tier 2 did not increase gas prices. Given this conclusion, it is unlikely that the 

sulfur content regulation of Tier 3 would result in higher gas prices for two reasons. 

First, relative to Tier 2, Tier 3 requires a much smaller reduction in the average sulfur of 

content of the fuel. Tier 3 requires a reduction of 20 ppm (from an average of 30 ppm to 10 

ppm), while Tier 2 required a reduction of 270 ppm (from 300 ppm to 30ppm). Tier 3 requires 

a reduction in sulfur that is 93% lower than that required of Tier 2. 

Second, relative to Tier 2, Tier 3 imposes a much smaller cost of compliance on refiners. EPA 

estimates that the sulfur requirement of Tier 3 will increase the cost of refining by 0.89 cents 

per gallon, which is considerably less than the agency’s prior cost estimate of Tier 2 (1.7 to 1.9 

cents per gallon). From the perspective of the refiners, Tier 3 will impose half the costs of Tier 

2. 

It has been noted by some commenters in this proceeding that Tier 3 would “...increase the 

price for gasoline paid at the pump by 6 to 9 cents per gallon (5). These comments cite a study 

prepared by Baker and O’Brien for the American Petroleum Institute (6). Although Baker & 

O’Brien concluded that Tier 3 would increase the marginal cost of refining by 6 to 9 cents per 

gallon, their study was silent on the associated retail price effect. Advocates for the refining 

industry often characterize the Baker and O’Brien study as concluding that Tier 3 will increase 

gasoline prices, but even the study’s authors were not willing to embrace this position. 

2 - EPA, Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel 

Standards, May 21, 2013, Proposed Rules (hereafter EPA Proposal). Fed Register pp. 29988-29989.

3 - Id. at footnote: 499, p. 29989.
Chapter 9: Economic Impact Analysis

9-8

4 - See Navigant Economics, Economic Analysis of the Implications of Implementing EPA’s Tier 3 

Rules, prepared for The Emissions Control Technology Association, June 14, 2012, p. 17-23 and 

Technical Annex (hereinafter “Navigant Study”).

5 - May 23, 2013 letter to Gina McCarthy from the Institute For Energy Research, p. 2.

6 - See Baker & O’Brien, Inc. Potential Supply and Cost Impacts of Lower Sulfur, Lower RVP 

Gasoline, prepared for the American Petroleum Institute, July 2011 (hereinafter “Baker & O’Brien 2011 

Study”), and The Baker & O’Brien, Inc., Addendum to Potential Supply and Cost Impacts of Lower 

Sulfur, Lower RVP Gasoline, prepared for the American Petroleum Institute, March 2012 (hereinafter 

“Baker & O’Brien 2012 Study”).

Commenter: Mercatus Center at George Mason University

REGRESSIVE EFFECTS 

While the EPA estimates that that this regulation will have a minimal impact (approximately 

one penny) on fuel costs, others have estimated the impact to be significantly greater, perhaps 

as much as 9 cents per gallon (18). Exactly how much gasoline prices may rise is difficult to 

say, but given that energy costs consume a higher proportion of low-income individuals’ 

income relative to high-income individuals, it is worth acknowledging that this regulation may 

impose a disproportionate impact on low-income individuals. Similarly, recent academic 

research has shown that regulations, such as the proposed regulation, are often more in line 

with risk preferences of wealthy households (19). It is unlikely that poor households are 

worried about the risks posed from PM2.5 and ozone when they face much larger risks 

elsewhere in their lives. The income they lose to comply with this regulation may be better 

utilized toward other risk mitigation. 

18 - David Tamm and Kevin Milburn, “Addendum to Potential Supply and Cost Impacts of Lower 

Sulfur, Lower RVP Gasoline,” (American Petroleum Institute, Houston, TX, March 2012).

19 - Diana Thomas, “Regressive Effects of Regulation.” (Working Paper No. 12-35, Mercatus Center at 

George Mason University, Arlington, VA, November 2012), http://mercatus.org/publication/regressiveeffects-regulation.

Commenter: Northeast States for Coordinated Air Use Management (NESCAUM)

To put the Tier 3 low sulfur impacts on the petroleum refining industry into perspective, it is 

instructive to summarize what has been previously required in other fuel programs. Over the 

past 13 years, EPA undertook three rulemakings, requiring significant reductions in the sulfur 

content of petroleum fuels. The Tier 2 regulation, promulgated in 2000, reduced the 

sulfur content of gasoline from a pre-regulation average of about 330 ppm down to 30 ppm and 

included an interim 120 ppm step. The highway diesel regulation, promulgated in 2001, 

reduced the sulfur content of diesel from 500 ppm down to 15 ppm. The non-road diesel 

regulation, promulgated in 2004, reduced the sulfur content of non-road fuel from a preregulation average of 3000 ppm down to 15 ppm, with an interim 500 ppm step. Compared to 

what is now proposed under Tier 3, these previous initiatives required very ambitious 

reductions. The refining industry met these challenges, supplying the market with compliant 

fuel while continuing to prosper economically. EPA’s structuring of these regulations played a 

critical role in facilitating the transition from high to low sulfur fuels in each case. 
Tier 3 Summary and Analysis of Comments

9-9

Specifically, EPA built several very important regulatory flexibilities for refiners into the 

gasoline and diesel fuel sulfur standards, including 1) providing several years of lead time for 

all refiners to add and/or enhance desulfurization capabilities, 2) ABT programs to encourage 

early compliance where possible and provide means for extending compliance dates where 

needed, 3) provisions for smaller refiners to further extend compliance deadlines and credit 

generation opportunities, 4) opportunities for refiners to integrate their desulfurization 

infrastructure planning processes across all three fuels programs, 5) interim sulfur limits to

allow refiners to phase their operations into compliance with the final standards, and 6) various 

hardship waiver provisions to provide a means to address unexpected circumstances. Most of 

these same flexibilities are built into the proposed Tier 3 program structure and in conjunction 

with comparatively modest requirements for reduction in sulfur will make for a relatively 

smooth transition from a 30 ppm average down to a 10 ppm average sulfur content. 

Some in the refining sector have made projections that the Tier 3 sulfur standards will force a 

number of refineries to close because the costs of compliance will be too high and/or the 

deadlines are too soon to make the necessary equipment and operational changes at the 

refinery. Consequently, the U.S. fuel markets allegedly will become increasingly more 

dependent on competitive foreign imports of products. Similar projections were made during 

promulgation of the previous rulemakings for low sulfur fuels. It is instructive to briefly review 

what actually occurred in the U.S. refining sector over the phase-in period of these regulations 

in order to gain a sense of what the likely outcomes will be under this more modest Tier 3 

scenario. 

Refining activity in the U.S. increased over the same period as indicated in Table 2 [p. 10 of 

EPA-HQ-OAR-2011-0135-4283-A1]. Particularly noteworthy is the fact that desulfurization 

capacity increased by 40 percent from 2000 to 2010, indicating that the domestic refining 

industry responded positively to the regulatory challenge and succeeded in dramatically 

reducing the sulfur content of fuels. 

Refiners’ original projections of very high compliance costs were principally based on the 

assumption that conventional energy-intensive hydrotreating technology would have to be 

deployed almost exclusively to achieve the low sulfur levels in the final products. In actual 

practice, refiners opted for a combination of technologies and facility efficiency improvements 

to cost-effectively remove fuel sulfur. At around the time of the first of the three rulemakings 

(Tier 2 gasoline), the National Petroleum Council issued a report (16) identifying several more 

cost-effective desulfurization technology improvements, classified either as “demonstrated” or 

“near commercial status.” By the time refiners had to select equipment for meeting Tier 2 

gasoline standards, there were several additional, less energy-intensive technology choices 

available to them (17). Despite industry predictions of insufficient lead time and manufacturing 

resources for timely compliance with the standards for all three rulemakings, early compliance 

was widespread, as evidenced by the surplus of credits under the ABT programs (18,19). 

[T]here are strong economic incentives for refiners to design and purchase the most energyefficient process equipment to minimize the cost of production. For example, most of the new 

or modified units expected to be involved in refinery projects designed to meet the proposed 

Tier 3 standards are fuel combustion units (e.g., process heaters). Because fuel cost (direct cost 
Chapter 9: Economic Impact Analysis

9-10

in the case of purchased natural gas and opportunity cost in the case of refinery-generated fuel 

gas) represents a significant component of total operating cost for such units, refineries will 

strive to maximize energy efficiency based on available technologies as part of their project 

design (20).

Regarding the issue of foreign imports of fuels, the discussion in the proposed rule points out 

that “despite refining industry projections that previously imposed diesel rules would lead to 

greater U.S. reliance on imports through major negative impacts on domestic refining, the 

reverse has actually occurred. Over the last 8 years, imports of gasoline and diesel fuel have 

continued to be the marginal supply, and have even dropped precipitously so that the U.S. is 

now a net exporter of diesel fuel and is importing half the gasoline that it did at its peak in 

2006. With the projected decline in future gasoline demand in the U.S. as vehicle fuel 

efficiency improves, gasoline imports are expected to continue to decline' (21). According to 

the U.S. Energy Information Administration’s 2013 Annual Energy Outlook, the U.S. is 

projected to be a net exporter of petroleum products at least through 2040. 

In response to favorable long-term economic outlooks, the North American refining industry is 

taking the initiative to make significant new investments in its capacity to increase the supply 

of petroleum products, including low sulfur products. Several refineries in the Northeast that 

recently were in danger of permanently closing have reopened or remained in business due to 

ownership changes and favorable developments related to petroleum and product supply. In 

2010, PBF Energy purchased the Valero refinery in Delaware City, DE. In conjunction with the 

purchase of the Delaware City facility, PBF Energy announced plans to invest $500 million to 

enhance its desulfurization capacity (22). In 2011, PBF Energy announced plans to invest $1 

billion at the Delaware City refinery to boost distillate output and heavy crude capacity. 

In 2010, Marathon Petroleum completed a $3.9 billion expansion, nearly doubling the capacity 

of its Garyville, LA refinery (23). This refinery is now the fourth largest in the U.S. and 

increases the ability of Gulf Coast refiners to augment the petroleum product needs in the 

Northeast. In 2009, Irving Oil Refinery (Saint John, New Brunswick) completed a $220 million 

upgrade. The majority of the work focused on improving its yield of ultra-low sulfur products. 

The Saint John Refinery is Canada’s largest and exports more than 80 percent of its products to 

the U.S. (24). 

16 - U.S. DOE. 2000. U.S. Petroleum Refining: Assuring the Adequacy and Affordability of Cleaner 

Fuels, June 2000.

17 - MathPro Inc. 2003. Evolution of Process Technology for FCC Naphtha Desulfurization: 1997-

2003; An Example of Technical Progress Induced by Environmental Regulation, March 2003.

18 - U.S. EPA, Summary and Analysis of the 2005 Highway and Nonroad Diesel Fuel Pre-Compliance 

Reports, EPA 420-R-06-012, June 2006.

19 - U.S. EPA. 2010. Summary and Analysis of the 2010 Nonroad Diesel Fuel Pre-Compliance Reports, 

EPA 420-R¬10-028, December 2010.

20 - 78 FR 29934, May 21, 2013

21 - 78 FR 29992, May 21, 2013.

22 - heatingoil.com. Delaware Refinery to Reopen with Plans to Produce Low-Sulfur Heating Oil and 

Biofuels, Posted June 2, 2010.

23 - The Times-Picayune, Marathon Completes $3.9 Billion Expansion in Garyville, March 25, 2010.
Tier 3 Summary and Analysis of Comments

9-11

24 - Irving Oil Company. 2009. Press Release: Irving Oil Refinery Completes $220 Million Investment 

Project, November 17, 2009.

Commenter: Pennsylvania Department of Environmental Protection (DEP)

DEP recognizes the important health benefits and cost-effectiveness of this proposed rule. 

Nevertheless, DEP has concerns about the impacts of costs to refiners of gasoline, projected 

gasoline cost increases to be passed along to the consumer.

Commenter: United States Congress, House of Representatives, Pennsylvania, 7th District

High gas prices have stretched Pennsylvania families thin already, and in the Philadelphia area, 

the refining industry is showing new promise after weathering a very tough economy for the 

sector. Adding new regulations without appropriate consultation with stakeholders— including 

the oil workers whose jobs could be put at risk through new mandates — and a thorough 

evaluation of the regulation's economic and consumer consequences is the wrong approach. 

Our Response:

These comments reflect two views: one, that the standards will have significant adverse 

effects; the other, that the standards will have negligible or no effects.

EPA estimates that the national average refinery costs incurred to comply with the fully 

phased-in Tier 3 sulfur control program with ABT program will be 0.65 cents per gallon, averaged 

over all gasoline. Section VII.B of the Preamble, Chapter 5 of the RIA, and Chapter 7.2 of this 

document discuss EPA’s fuel cost estimates in detail. As discussed in Preamble Section X.C. 

and RIA Chapter 9.3, EPA considers this impact to be small, and thus to be a barely measurable 

contributor to gasoline prices. We do not consider this view to contradict the study by 

Navigant (cited by ECTA) that was not able to find any impacts from the larger Tier 2 

standards; in that case, and likely in the case of Tier 3 as well, the small increases may be 

swamped by the general variability in fuel prices. We agree with NESCAUM that the refinery 

sector on the whole has weathered the Tier 2 standards and is likely to face less additional 

difficulty with the Tier 3 standards. Because the impact of the standards on gasoline prices is 

expected to be small, we do not believe that the standards will contribute in a measurable way 

to household fuel costs. We expect this impact to be small even for low-income households. 

An increase of 0.65 cents per gallon for gasoline is less than 0.2 percent. The lowest quintile of 

U.S. households in 2012 spent $1,222 on gasoline and motor oil (Bureau of Labor Statistics, 

Consumer Expenditure Survey, Quintiles of income before taxes, 

http://www.bls.gov/cex/#tables); an increase of 0.2 percent is under $3 per year, an amount that 

is unlikely to cause significant additional hardship to low-income households. 

Households will, in addition, receive the benefits of cleaner air. As stated in Preamble 

Section XII.J, “This final rule will reduce emissions from vehicles across the nation, both new 

vehicles (beginning in model year 2017, when the vehicle standards start to apply) and existing 

vehicles (as soon as the lower-sulfur gasoline becomes available in 2017). As such, this rule

increases the level of environmental protection for all populations. As discussed in Section 
Chapter 9: Economic Impact Analysis

9-12

III.C.7, there is evidence that minority populations and low-income populations live 

disproportionately near high-traffic roadways, where concentrations of many air pollutants are 

elevated. We expect this final rule to increase the level of environmental protection for these 

populations.”

In addition to receiving many public comments, both in public hearings and submitted 

in writing, EPA has conducted significant consultation with stakeholders in developing these 

standards; see Preamble Section XI. Section V.L of the Preamble, Chapter 4 of the RIA, and 

Chapter 5 of this document discuss the feasibility for refineries to meet these standards. As 

discussed in those, we believe that refineries will not be put at undue risk. We agree with 

Clean Air Watch that previous rulemakings have not led to significant adverse impacts in the 

refining sector, nor do we expect these standards to have significant adverse impacts. EPA 

agrees that the Tier 3 standards, as well as the other standards cited by Clean Air Watch, have 

produced significant public health benefits. The benefits of Tier 3 are discussed in Preamble 

Section VIII and RIA Chapters 6-8.

Preamble Section X.D, RIA Chapter 9.3.2, and Chapter 9.3.2 of this document provide 

EPA’s examination of employment impacts on refineries. EPA does not quantify most of the 

employment impacts of the standards. Most likely, employment will be gained in some sectors 

or locations, and it may be reduced in other sectors or locations; the net effect is expected to be 

small. We note that the United Steel, Paper and Forestry, Rubber, Manufacturing, Energy, 

Allied Industrial and Service Workers International Union (USW) and the International Union, 

United Automobile, Aerospace & Agricultural Implement Workers of America (UAW) 

provided comments supportive of Tier 3, including mention of expected positive job impacts 

from the standards.

9.3. Employment Impacts

What Commenters Said:

Commenters: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM)

Jobs. Mandatory government regulations requiring capital expenditures and the creation of 

temporary jobs for unjustified new specifications constitute inefficient uses of market financial 

resources. As such, it makes little sense for Navigant or EPA to count the mandated costs of a 

regulation, i.e. Tier 3, as “benefits” when in reality economic growth is slowed from what it 

could have been with more efficient use of capital. 

Commenter: Marathon Petroleum Company LP (MPC)

Jobs. An objective economist would be aware that mandatory government regulations requiring 

significant capital expenditures and the creation of jobs to perform unnecessary gasoline sulfur 

reductions is an inefficient use of market financial resources, pulling capital from more 

efficient uses. As such it makes little sense for Navigant or EPA to count the mandated costs of 
Tier 3 Summary and Analysis of Comments

9-13

a regulation as benefits when in reality economic growth is slowed from what it could have 

been with more efficient use of capital. 

Commenter: Care 2 (comment campaign)

The new standards will also create jobs as automakers apply advanced technologies and 

refineries upgrade their equipment. 

Commenter: Union of Concerned Scientists (comment campaign)

I support Tier 3 standards that will: create new jobs at refineries, installing and operating sulfur 

reduction equipment, and in the automotive sector, developing and manufacturing cleaner 

vehicles. 

Commenter: Medical Advocates for Healthy Air

Financial Benefits: In purely economic terms, the implementation of cleaner fuel standards will 

create 5,300 permanent jobs in the operation and maintenance of new refining equipment as 

well as over 24,000 new jobs, over a three year period, for equipment installation at the 

nation’s refineries. The industry which manufactures emissions control technology generated 

$12 billion of economic activity and accounted for 65,000 US jobs in 2010. Lower traffic 

pollution will lead to improved health outcomes and greatly reduce absenteeism from work and 

school, thus increasing productivity. 

Commenter: Mercatus Center at George Mason University

EMPLOYMENT EFFECTS 

The EPA cites three different ways in which regulations may impact employment: demand 

effects, cost effects, and factor-shift effects. The first method reduces employment in a 

regulated industry, the second increases it, and the last effect is ambiguous. However, the EPA 

should be careful to acknowledge that both jobs gained and jobs destroyed are costs of the 

proposed regulation. Ideally, compliance jobs should be minimized, not viewed as a benefit of 

a regulation (15). 

The EPA should consider some of the long-term effects of its rules on those who lose their jobs 

at this unusual moment in time, with unemployment at a level that exceeds historical norms. 

The literature shows that these effects can be significant. For example, recent estimates of 

earning losses resulting from job loss range from 1.4 years of earnings in times of low 

unemployment to 2.8 years during times of high unemployment (16). Similarly, research shows 

that after reemployment it can take as long as 20 years for workers to catch up on lost earnings, 

largely due to skill mismatches between the jobs lost and the new jobs created in the economy 

(17). Additionally, the EPA should acknowledge that those who lose jobs and those who gain 

them are not in fact the same individuals; vastly different skill sets may be required in one type 

of employment relative to the other. Moving from one area of employment to the other may 

require significant skills retraining if those laid off are to be reemployed in the new line of 
Chapter 9: Economic Impact Analysis

9-14

compliance work. 

15 - See for example Keith Hall, 'Goodbye to Green Jobs, You Won’t Be Missed,” Forbes, April 4, 

2013, http://www.forbes.com/sites /realspin/2013/04/04/goodbye-to-green-jobs-you-wont-be-missed/.

16 - Keith Hall, 'The Employment Costs of Regulation.” (Working Paper No. 13-06, Mercatus Center at 

George Mason University, Arlington, VA, March 2013), http://mercatus.org/publication/employmentcosts-regulation.

17 - Ibid.

Commenter: Natural Resources Defense Council (NRDC)

The Tier 3 new vehicle and fuel standards will add thousands of jobs to the U.S. economy by 

requiring new technologies to clean up gasoline and clean vehicle exhaust. 

New Vehicle and Fuel Standards will Create Thousands of Jobs. The Tier 3 standards will add 

thousands of jobs to the U.S. economy by requiring new technologies to clean up gasoline and 

clean vehicle exhaust. Importantly, Baker and O’Brien found that the Tier 3 regulations would 

not result in refinery closures. With continued operation, some refineries will have to deploy 

new technologies. Similarly, jobs will be created in the automobile manufacturing and 

automobile parts sectors to add new technologies. Total long-term job estimates in both the 

refining and automotive sectors range from at least about 2,000 jobs in EPA’s low-end 

assessment to nearly 5,300 jobs estimated by Navigant Economics (29). In the short-term, EPA 

and Navigant agree that thousands of workers are expected be employed to design and build the 

needed modifications to refineries. 

29 - Schink, op. cit.

Commenter: Northeast States for Coordinated Air Use Management (NESCAUM)

In addition to critical air quality, public health, and environmental benefits, Tier 3 would 

promote economic growth and create jobs throughout the U.S. According to the Manufacturers 

of Emission Controls Association, the emission control technology industry provides 65,000 

domestic jobs and accounted for $12 billion in economic activity in the U.S. in 2010 (7).

7 - Manufacturers of Emission Controls Association. 2011. Press release: MECA Highlights Economic 

Benefits of Mobile Source Emissions Control Industry. Available online at 

http://www.meca.org/galleries/defaultfile/MECA%20economic%20benefits%20press%20release%20031111.pdf.

Commenter: Sierra Club, Clean Air Watch, Respiratory Health Association

Further, the new standards will bring more American jobs as parts suppliers develop and build 

new technology and refiners and automakers install it. According to a study by Navigant 

Economics, implementation of cleaner tailpipe standards would create nearly 5,300 permanent 

jobs in the operation and maintenance of new refining equipment, as well as more than 24,000 

new jobs over a three-year period as refineries install new equipment.3 [EPA-HQ-OAR-2011-0135-4308-A1 
Tier 3 Summary and Analysis of Comments

9-15

p. 2-3]

3 Navigant Economics. Economic Analysis of the Implications of Implementing EPA’s Tier 3 Rules. 

June 2012. http://www.ectausa.com/061212-Economic-Analysis-of-the-Implications-of-Tier-3-SulfurReduction-Final embargoed.pdf

Commenter: United Steelworkers Union (USW)

In fact U.S. refiners who currently export to 10ppm sulfur standard countries have already 

made efforts to upgrade assets to compete. As indicated on the April second 2013 tier three call 

organized by EPA, out of the one hundred and eleven (111) U.S. refineries impacted by the 

proposed rule, twenty-nine (29) can already meet the new standards or need to make 

operational changes. Sixty-six (66) will need to make equipment modifications and sixteen (16) 

will need to acquire additional equipment. These modifications will improve the health and 

welfare of the communities our members live and work in and provide economic development 

in the areas where the refineries operate.

The modifications and upgrades required under the proposed rule will also provide sustained 

employment for our members employed at refineries as well as create additional jobs. The 

Emissions Control Technology Association (ECTA) contracted with Navigant Economics to 

review the impacts of the EPA Tier 3 standards and found installation of the refinery 

modifications produces almost 24,500 jobs for full-time equivalent employees in the upgrading 

of facilities to comply with the rule and the continuing annual operation of the refinery 

modifications produces almost 5,300 jobs for full time equivalent employees (1).

As stated above, the proposed rules will allow domestic refining capacity to remain globally 

competitive and will provide significant employment opportunities for workers who 

manufacture, install, and operate the necessary refinery equipment to produce 10ppm sulfur 

gasoline.

1 - http://www.ectausa.com/061212-Economic-Analysis-of-the-Implications-of-Tier-3-SulfurReduction-Final embargoed.pdf

Our Response:

Most of these commenters cite estimates of job increases associated with the Tier 3 

standards. As discussed in Preamble Section X.D and RIA Chapters 9.2.2 and 9.3.2, EPA does 

not quantify most of the employment impacts of the standards and thus does not evaluate these 

estimates. Most likely, employment will be gained in some sectors or locations, and it may be 

reduced in other sectors or locations; the net effect is expected to be small.

The Mercatus Center recommends that “the EPA should be careful to acknowledge that 

both jobs gained and jobs destroyed are costs of the proposed regulation. Ideally, compliance 

jobs should be minimized, not viewed as a benefit of a regulation.” This assertion is confusing, 

in that it implies that any effect on employment, positive or negative, is costly. MPC and API 

and AFPM argue that employment impacts should not be counted as benefits. The discussion 

in Preamble Section X.D of the employment impacts of the standards is intended to identify 

additional ways that these standards will affect the public. Employment clearly provides 
Chapter 9: Economic Impact Analysis

9-16

benefits to the people who are employed, and reducing unemployment is considered a desirable 

outcome in times of high unemployment. EPA disagrees that minimizing compliance jobs 

should be an independent objective of this rulemaking. The objective of the program is to 

improve air quality through reductions in vehicle emissions; we provide information 

concerning employment impacts as part of our overall analysis of economic impacts from the 

rule.

The Mercatus Center also requests that we consider the long-term effects of 

unemployment on workers who may lose jobs, and that we acknowledge that those who lose 

jobs may not be the same people who gain jobs. We recognize there are costs to workers who 

shift from one job to another,[1] but we also note, as discussed in Preamble Section X.D., that 

we expect very small employment impacts from the standards. 

We disagree with API and AFPM that the standards are “unjustified,” and with MPC 

that these standards are “unnecessary;” see Preamble Section VIII and RIA Chapter 8 for an 

assessment of the benefits of the standards and the benefit-cost analysis, which show 

significantly positive net benefits. In sum, as earlier explained in Chapter 2.1 of this document, 

we believe that the final rule implements the Tier 3 program in a manner consistent with our 

legal obligations, with sound science, and with sound environmental, energy, and economic 

policy, and we disagree with comments suggesting that the Tier 3 rule is not justified. The Tier 

3 program, including the gasoline sulfur standards, will reduce ambient levels of air pollution 

that endanger public health and welfare and will provide important benefits to the public such 

as preventing PM- and ozone-related premature deaths. The Tier 3 Preamble very clearly 

explains the need for the Tier 3 standards in Section II, our technical justification for the 

vehicle emission controls in Section IV, and technical justification for the fuel standards in 

Section V. A vast body of underlying technical analyses supporting the Tier 3 standards can be 

found in our Regulatory Impact Analysis, which reflects the best methods, data and 

assumptions available at the time of the rulemaking analysis. We thus disagree that 

investments to meet the standards are an inefficient use of resources.

[1] E.g., Jacobson, Louis S., Robert J. LaLonde, and Daniel G. Sullivan, “Earnings Losses of Displaced 

Workers.” American Economic Review 83(4) (1993): 685-709.

9.3.1. Employment Impacts in the Auto Sector 

What Commenters Said:

Commenter: BlueGreen Alliance

The automotive industry has added more than 200,000 jobs since 2009, and the U.S. auto 

market has had three consecutive years of double digit growth due in large part to rising 

demand for these cleaner cars in the market. 'Gearing Up,' our report last year by the BlueGreen 

Alliance and the American Council for an Energy Efficient Economy, estimated that meeting 

the 54.5 mile per gallon rule will create more than 500,000 jobs through the U.S. economy by 

2030. Building cleaner, more efficient cars creates jobs by sending money otherwise spent on 
Tier 3 Summary and Analysis of Comments

9-17

fuel back into the U.S. economy, and also through the development and production of new, 

more efficient vehicle components.

Americans are working in a variety of industrial sectors in the Midwest and across the country.

Members of the auto workers and steel workers will manufacture vehicle emission control 

technologies to meet these standards. As the BlueGreen Alliance's Regional Program Manager 

for Illinois and Indiana, I am frequently in contact with people working in the automotive 

industry.

Indiana ranks third in the country and Illinois seventh for jobs in the automotive parts industry, 

and they are also both in the top 10 for States with jobs in automotive assembly. The Tier 3 

standard will bolster the auto industry's ability to meet a strong fuel efficiency standard and 

generate net positive economic outcomes.

Commenter: Business for Innovative Climate and Energy Policy (BICEP)

Additional benefits and jobs in the auto and emission control industries, which are significant 

drivers of the economy, will result from the development and production of Tier 3 technology. 

Commenter: California Air Resources Board (CARB)

Additionally, we believe that given the magnitude of compliance costs relative to the size of the 

domestic economy, U.S. EPA's more qualitative approach for estimating employment effects 

using the Morgenstern et al. framework instead of relying on economy-wide modeling is 

reasonable. 

Commenter: Ceres Investor Network on Climate Risk

Additional benefits and jobs in the auto and emission control industries, which are significant 

drivers of the economy, will result from the development and production of Tier 3 technology. 

 

Commenter: Emissions Control Technology Association (ECTA)

Although Navigant did not estimate the impact of the rule on the auto and parts industries, we 

disagree with EPA’s conclusion that the associated employment effect would be negligible. We 

draw two conclusions from the RIMS model. The model shows that for every $1 million 

investment in new automotive parts, the RIMS multipliers imply 5.9 jobs (14). 

We believe that these positive short-term employment effects are quite important as a matter of 

policy. The U.S. economy is currently operating under its full potential as witnessed by the 

high unemployment rate of 7.6 percent, as well as testimony by the Congressional Budget 

Office (CBO) that the rate will stay above 7.5 percent through 2014. CBO also stated in its 

testimony that economic output will stay below its potential level until 2017 (15). The 

simulative effect of new investment is most pronounced during periods of less-than-full 

employment. In the case of Tier 3, labor and other resources that are currently underutilized 
Chapter 9: Economic Impact Analysis

9-18

will be utilized by the refining and automobile makers as they comply with the new rule. This 

will increase economic activity and employment at a time when the nation desperately needs it. 

14 -

http://www.cityofventura.net/files/file/commdevelop/Economic%20Development/Economic%20Inform

ation-Data%20Book/18-Regional%20Input-Output%20Modeling%20System.pdf

15 - CBO Testimony, CBO Budget and Economic Outlook, February 15, 2013, 

http://www.cbo.gov/publication/4394.

Commenter: Sierra Club (comment campaign)

The new standards will also create jobs as automakers apply advanced technologies and 

refineries upgrade their equipment. 

Commenter: Sierra Club

The new standards will not only reduce air pollution, they will create jobs as auto part suppliers 

manufacturer the technologies that reduce vehicle emissions. Auto makers apply advanced 

vehicle technologies and refineries upgrade their equipment. This is a win-win for public 

health and the economy, and EPA should move forward to finalize these standards without 

delay.

Commenter: United Automobile Workers

These proposed rules are part of a comprehensive approach to creating the next generation of 

clean vehicles. They go hand-in-hand with the new CAFE standards that were passed to 

regulate the fuel efficiency of our nation’s vehicles over the next twelve years. Automakers are 

investing billions of dollars in retooling and expanding to produce the cleaner cars that 

consumers are demanding. Manufacturing advanced vehicles and their fuel-efficient 

components here in the United States is a crucial opportunity to develop domestic jobs that are 

sustainable in the long-term. 

Commenter: Wespath Investment Management

It is also anticipated that the development and production of Tier 3 technology will result in 

additional jobs in the auto and emission control industries. 

Our Response:

All these comments suggest that these standards will increase employment in the auto 

sector. EPA believes that this outcome is possible, though we do not expect a large effect, 

because the standards are not expected to have a large effect on auto production or costs.

ECTA argues that job impacts will be not only positive in the auto and auto parts sectors, but 

substantially more positive than EPA states, based on Regional Input-Output Modeling System 

(RIMS) multipliers that find increases of 5.9 jobs for every $1 million investment in new auto 

parts. Multiplier impacts trace the entire chain of job impacts associated with an expenditure, 

including factors such as changes in employment in retail establishments due to changes in 
Tier 3 Summary and Analysis of Comments

9-19

workers in the auto sector. Because the expenditures will occur when unemployment is still 

high, ECTA argues, it is important to consider the multiplier effects of the expenditures that are 

embedded in the RIMS multipliers. As discussed in Preamble Section X.D, the multiplier 

impacts of expenditures depend heavily on the state of the macroeconomy. Because of 

uncertainty over the state of the economy when the increased expenditures will occur, EPA has 

not quantified the multiplier impacts due to changes in employment associated with these 

standards. As discussed again below, some expenditures, perhaps especially in the refinery 

sector, will occur before the standards take effect, to get the manufacturing processes in place 

to meet the standards. These near-term expenditures may have some multiplier effects, because 

they are more likely to have their impacts during the current period of above-average 

unemployment. In contrast, the ongoing costs of complying with the standards, which 

contribute most directly to price increases, are likely to come in future years, when it is 

expected that unemployment rates will be lower.

9.3.2. Petroleum Industry Employment Impacts 

What Commenters Said:

Commenters: Attorney General of Connecticut, et.al; Attorney General of New York, et.al; 

BlueGreen Alliance; Business for Innovative Climate and Energy Policy 

(BICEP); Ceres Investor Network on Climate Risk; Clean Air Council; League 

of Conservation Voters (comment campaign); Sierra Club; Wespath Investment 

Management

The refinery upgrades necessary to meet the lower sulfur gasoline standards are expected to 

generate 24,500 installation jobs during the first three years of the program and 5,300 

permanent jobs.

Commenter: Emissions Control Technology Association (ECTA)

Tier 3 Is Likely to Have a Positive Impact on Employment and the Economy: We disagree with 

EPA’s conclusion that the proposed rule would have an ambiguous effect on employment in the 

refining sector. We find that the employment effect will be positive and significant. 

EPA concludes that: 

“...it is not evident whether the proposed rule would increase or decrease employment in the 

refining sector. However, given the small anticipated reduction in quantities sold, it appears 

that the rule would not have major employment consequences for [the refining] sector” (7). 

We disagree with this conclusion and believe that the employment impact on the refining 

industry will be positive and potentially quite significant. It could result in the creation of 

24,500 jobs (i.e., full time equivalents or FTEs) over the three years during the installation of 

desulfurization equipment and 5,300 jobs for the operation and maintenance of the equipment 

over the longer term. We draw this conclusion from a study by Navigant Economics on the job 

impact of Tier 3 on the refining industry (8). 
Chapter 9: Economic Impact Analysis

9-20

We agree with EPA’s use of the “demand effect,” the “cost effect,” and the “factor shift effect” 

in analyzing the impact of the rule on employment in the refining and auto sectors (9). But, we 

draw a sharply different conclusion when applying this analytical approach to the refining 

sector. 

First, EPA concludes that the demand effect is expected to be negative; that is, the cost of Tier 

3 to refiners will be passed on to consumers in the form of higher gasoline prices, which will 

reduce the demand for gasoline and hence output by the refining sector. As explained in detail 

in Section I of this submission, we find that the increased cost to refiners is unlikely to be 

passed on to consumers; accordingly, we do not expect any negative demand effect arising 

from the rule. Even if a portion of the rather small costs to refiners were passed along, the 

demand effect would be minimal because the demand for gasoline is relatively inelastic as 

consumers have no close substitutes for gasoline. 

Second, EPA concludes that in the short-term the “cost effect” is likely to be positive; that is, 

the increased investment by the refining industry to comply with Tier 3 will generate increased 

employment over the short-run. We agree with this conclusion, but we find that the cost effect 

will be much larger than EPA’s estimate. 

EPA expects that refiners will invest $2.2 billion between 2014 and 2019, which will increase 

employment by 7,000 jobs for design, engineering, and construction of the desulfurization 

equipment (10). We conclude from the Navigant study that the refining industry’s initial 

investment of $3.9 billion (relating to installation expenditures) will create 24,500 FTEs for the 

first three years of implementation. The Navigant estimate is generated through the use of the 

RIMS II input-output model developed and maintained by the Bureau of Economic Analysis. In 

addition to a significant positive employment effect, this model also projects that the increased 

investment by the refining industry will generate over $2 billion in economic value-added per 

year over three years, $1.2 billion annually in increased employment compensation, and $0.5 

billion per year in tax revenue for federal, state, and local government (11). 

We also conclude from the Navigant study that a further 5,300 jobs will be created from the 

$0.5 billion per year in operation and maintenance costs associated with the desulfurization 

equipment after it is installed. This will generate $0.6 billion per year in economic value added, 

$0.3 billion in employment compensation annually, and $0.1 billion in increased tax revenue 

per year (12). EPA gave no consideration to the economic impact of the expenditures that are 

related to the operation and maintenance of the new equipment. 

Finally, like EPA, we did not analyze the “factor shift effect”; that is, the changes in labor 

intensity associated with a regulation that drives demand for new technology that is more or 

less labor intensive than the “old technology.” Because Tier 3 would not require refineries to 

deploy a new technology— instead, the same technology used to reduce sulfur would be 

intensified—we think the concept of factor shift effect is not applicable here. 

EPA concludes: 
Tier 3 Summary and Analysis of Comments

9-21

“...while we do not have an estimate of the direction of the overall effect of the proposed rule 

on auto-sector employment, we expect it to be imperceptible (13). 

7 - EPA Proposal, Fed. Reg. at p. 29992.

8 - Navigant Study at pp. 25-27.

9 - EPA Proposal, Fed. Reg. at p. 29991.

10 - EPA Proposal, Fed. Reg. at p. 29999.

11 - Navigant Study, pp. 25-27 and footnote 42.

12 - Navigant Study, pp. 25-27.

13 - EPA Proposal, Fed. Reg. at 29991.

Commenter: National Association of Clean Air Agencies (NACAA)

Tier 3 will also provide new employment opportunities. In its draft RIA, EPA projects that the 

work refineries will need to undertake to satisfy the Tier 3 requirements will create about 1,000 

front-end design and engineering jobs and 6,000 construction jobs for a total of 7,000 new jobs. 

The agency notes that the petroleum sector employed about 65,000 workers in 2009. Therefore, 

the new jobs to be created as a result of Tier 3 would increase employment in the petroleum 

sector by over 10 percent compared to 2009 levels. 

Our Response:

Most of these comments cite Navigant Economics for positive and substantial job 

impacts; NACAA cites EPA’s estimates from the NPRM. 

As discussed in Chapter 9.3.1 of this Summary and Analysis of Comments document, 

EPA is not using multiplier effects for its estimates of employment impacts here, as does the 

Navigant Economics study, because of uncertainty over the state of the macroeconomy at the 

time that these expenditures will occur. As discussed in Chapter 9.2 of this document, we do 

not consider our finding of a small demand or output effect to contradict Navigant Economics’ 

finding of no demand effect; it is possible that the effect of the standards on price, and thus on 

fuel sales, is too small to measure.

EPA has revised its employment estimates for refineries for this final rule. As 

discussed in Preamble Sections V.L.3.e and X.D.2, to meet the Tier 3 sulfur standards, EPA 

now estimates that refiners are expected to invest $2 billion between 2012 and 2019 and utilize 

approximately 250 front-end design and engineering jobs and 1,500 construction jobs. As the 

petroleum sector employed approximately 71,000 workers in 2011, this temporary increase in 

employment will be small when compared to 2011 levels.

Commenters: American Petroleum Institute (API) and the Association of Fuel & 

Petrochemical Manufacturers (AFPM); Marathon Petroleum Company LP 

(MPC)

Refining sector jobs:

We recommend that EPA removes the reference and benefits from 1,600 “jobs gained in the 

refinery sector”. First, it should be pointed out that these are temporary constructions jobs and 
Chapter 9: Economic Impact Analysis

9-22

not permanent jobs gained in the refinery sector. Second, this estimate was based on a single 

study by Morgenstern et al. “Jobs versus the environment: an industry level perspective. J. Env. 

Econ. and Manag. 43:412-436.” EPA used a figure of 2.17 jobs created per M$ of 

expenditures (1987 dollars scaled to 1.289 G$ costs in 2017.) The applicability of the 

Morgenstern study, which focuses on jobs associated with refinery emission reductions, to Tier 

3 gasoline sulfur reduction is questionable. 

Commenter: Chevron Products Company

EPA does not account for the economic hardship and resulting impact on local and regional 

economies incurred as a result of the above average cost of production for some of the 

refineries. This analysis also alludes to increases in employment in the refining sector resulting 

from past regulations without any reference to the economic context of that time or the global 

competitive forces. This leads the reader to conclusions without any fact or basis. EPA makes 

the argument that ‘While closing refineries has a negative effect on industry employment, it is 

likely that the increased refining capacity at many of the remaining plants had a positive effect 

on industry employment.’ Increases in production may not result in any significant increases in 

employment to offset the impact of closing refineries.’ If throughput is increased without the 

addition of new equipment trains to manage, the labor needed to keep the refinery running 

would be about the same. 

Our Response:

In the NPRM, EPA presented the Morgenstern et al.-based estimate, not as a conclusive 

estimate, but rather as one estimate that we too consider of unclear applicability to the 

standards. As discussed in Section X.D of this final rule, we are now using estimates from 

Berman and Bui (“Environmental Regulation and Labor Demand: Evidence from the South 

Coast Air Basin.” Journal of Public Economics 79(2) (2001): 265-295) that "employment 

effects are very small, generally positive, but not significantly different from zero." As 

discussed above, to meet the Tier 3 sulfur standards, EPA now estimates that refiners are 

expected to invest $2 billion between 2012 and 2019 and utilize approximately 250 front-end 

design and engineering jobs and 1,500 construction jobs. As the petroleum sector employed 

approximately 71,000 workers in 2011, this temporary increase in employment will be small 

when compared to 2011 levels.

Chevron Products Company states that we do not account for the hardship on local and 

regional economies due to the increase in refinery costs. Because we do not consider 

employment impacts to be large, even at local and regional scale, we do not expect large 

impacts on the economies at that scale. Chevron also states that our employment analysis does 

not account for economic context or global competitive forces. These are both considered in 

Preamble Section X.D and RIA Chapter 9.3. As discussed there, we recognize that 

employment impacts depend on the overall state of the macroeconomy. We also discuss the 

effects of Tier 3 in a global context: Canadian and Caribbean refineries are expected to have 

costs similar to those of U.S. refineries, while European refineries are already producing 

gasoline to a 10-ppm sulfur cap for Europe. EPA and Chevron appear to agree that minor 

changes in production are not expected to lead to significant changes in employment.
Tier 3 Summary and Analysis of Comments

10-1

10. Statutory Process and Executive Orders

What We Proposed:

The comments in this chapter correspond to Section XII of the preamble to the proposed 

rule and address statutory process and executive orders as they relate to the Tier 3 rule. A 

summary of the comments received and our responses to those comments are located below (and 

in Section XII of the preamble to the final rule).

10.1. Administrative Procedure

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM)

EPA is pursuing a flawed process in developing this rule. It is outrageous for EPA to hold public 

hearings as the docket continues to be populated with supporting information. It is invalid for 

EPA to hold these hearings in advance of publishing the rule in the Federal Register.

EPA must follow the Clean Air Act’s procedural requirements. Section 307 sets clear 

requirements for the rulemaking process that begins with EPA first publishing a proposed rule in 

the Federal Register. In this publication, EPA shall specify the comment period. EPA cannot set 

a deadline for public comments on a proposal that has not yet been published, and the 

supplemental publication that merely identifies the hearing dates and locations is a clear attempt 

to circumvent public participation in the rulemaking process.

Clean Air Act Section 307 also requires EPA must include with the Federal Register publication 

factual data on which the proposed rule is based, the methodology used in obtaining the data and 

in analyzing the data, and the major legal interpretations and policy considerations underlying 

the proposed rule. In short, this means all the information EPA uses as the basis for the rule must 

be available. As of last week, over 700 new documents had been added to the docket, leaving not 

time to analyze the information to provide meaningful input.

Once the proposed rule is published, the comment deadline needs to be revised. Another public 

hearing should be scheduled, and it must be held long enough after publication to allow for 

public review of all of EPA’s data and analysis. The availability of a pre-publication rule cannot 

be used as a reason to truncate the review period.

Commenter: Chevron Products Company

Chevron does not agree with the notice and comment process that EPA followed for publishing 

the Tier 3 NPRM. The delayed publication of the NPRM and the accelerated timeline for review 

and comment establishes a poor precedent for future rulemakings. A proposal of this importance 
Chapter 10: Statutory Process and Executive Orders

deserves to be presented with a transparent administrative process and sufficient time for review 

and comment.

Regarding the administrative process for the Tier 3 NPRM, Chevron is disappointed by the 

procedure that EPA has followed for publishing the proposal and soliciting comments. The 

NPRM was published in the Federal Register on May 21, 2013, and EPA established a comment 

submittal deadline of July 1, 2013. This is a 41 day comment period for a proposal that 

comprises several thousand pages of regulatory text, analysis, test data, and various other docket 

submissions. A proposal of this length and complexity deserves to be presented with a 

transparent administrative process and sufficient time for review and comment.

We understand from prior discussion with EPA that the Tier 3 NPRM has been under 

development and was largely completed for perhaps a year or more prior to its release. There has 

been ample time to inform the public of the proposal and conduct the notice and comment 

process without resorting to an unrealistic, accelerated schedule. We are concerned by the 

precedent that this establishes for future rulemakings. EPA owes it to all Tier 3 stakeholders and 

the American public to conduct these proceedings with the highest regard for transparency, 

fairness, and due diligence. 

Commenter: Chrysler Group LLC

EPA’s Procedural Obligations Under the Clean Air Act:

Chrysler observes that EPA failed to comply with its procedural obligations under the Clean Air 

Act (CAA) in issuing the proposed rule. Specifically, CAA section 307(d)(3) states that a “notice 

of proposed rulemaking [must] be published in the Federal Register” and must “specify the 

period available for public comment” (40). The CAA further requires EPA to “ensure a 

reasonable period for public participation of at least 30 days” (41). Here, EPA published a 

Federal Register notice on April 8, 2013, announcing not the rule, but that public hearings for the 

proposed Tier 3 rule would be conducted on April 24, 2013 and April 29, 2013. Without having 

published the actual rule, that federal register notice also announced that the comment period for 

the proposed Tier 3 rulemaking would end on June 13, 2013. Curiously, then, the proposed Tier 

3 rule itself was not published in the Federal Register until May 21, 2013, less than 30 days prior 

to June 13, 2013, and EPA did not “refresh” the comment period in the proposal in order to 

comply with the CAA.

EPA cannot, consistent with the CAA, establish a public comment period prior to publishing the 

actual proposed rule on which the public is to participate/comment, especially where the 

resultant comment period does not comport with the CAA. As such, EPA’s initial decision to 

close the public comment period on June 13, 2013—24 days after the proposed rule was 

issued—violated the CAA’s minimum 30-day public comment requirement. Only after EPA 

received correspondence pointing out these procedural flaws did the agency extend the comment 

deadline to July 1, 2013. Chrysler commends EPA for extending the comment period and 

complying with the statutory obligation and urges the Agency to refrain from taking such an 

approach in future notice-and-comment rulemaking actions. 

40 - 42 U.S.C. § 7607(d)(3). 
Tier 3 Summary and Analysis of Comments

10-3

41 - 42 U.S.C. § 7607(h).

Commenter: Marathon Petroleum Company LP (MPC)

EPA has also taken several questionable steps in the process that it has followed for this 

proposed rulemaking. Most notably, EPA conducted field hearings for this proposal prior to 

official publication of the proposal in the Federal Register. EPA also failed to provide the 

affected stakeholders with sufficient time to comment on a rulemaking of this magnitude. And 

on June 25, 2013 (less than one week before comments were due) the Agency was still adding 

large supporting documents to the docket. 

As a result of the overall lack of justification for these fuel changes and the significant time 

needed for review of EPA documents, MPC asserts that finalizing this proposal would be 

arbitrary and capricious and unlawful. EPA should either drop the current proposal or restart the 

proposal process in a manner that allows all stakeholders to have sufficient time to analyze and 

understand all the documents and issues involved in this complex rulemaking and to make 

appropriate comments. EPA must strictly re-examine the purported benefits of this rule and its 

real costs.

My comments today aren’t really on the rule – the proposal itself, but the process that EPA is 

using in this rulemaking, and the fact that they’ve created a very unusual and unacceptably 

shortened comment period, which won’t allow adequate public comment on the rule. And it’s a 

rule that has significant impact on both my industry and the consumer.

It’s taken EPA at least two years to get to this point, and the administrative record right now 

reflects a very complex set of documents consisting of thousands of pages of text. EPA has 

chosen to hold only two field hearings on this proposal, one today and one last week, and unless 

they actually printed the proposal in the Federal Register today, we haven’t got an official copy 

of the proposal yet.

The two field hearings are occurring way too early, and simply stated, EPA has provided the 

stakeholders with insufficient time to analyze the overwhelming quantity of data and documents 

offered in support of the Agency’s proposed action. We are still searching the docket trying to 

find several key documents that EPA references in the draft Regulatory Impact Analysis, and we 

have no assurance that the proposal we’re working from is going to be the final proposal since 

each page has got a memo attached to it that says this is not an official version.

The public and the regulated community should be allowed at least the typical 90 days to review 

and comment on any proposal, especially this proposal. And the EPA shouldn’t shorten the 

process that it has historically used in developing the proposed rules.

Affected parties deserve and should be granted adequate time to review the hundreds of 

documents that the Agency has placed in the docket in the last two weeks, and those that EPA is 

still placing in the docket. According to EPA – or according to us, we recommend that EPA 

schedule a third hearing that’s a minimum of 30 days after the publication of the Proposed 

Notice of Rulemaking in the Federal Register, and after all the documents are put in the docket.
Chapter 10: Statutory Process and Executive Orders

This would allow all the interested parties to have time to review the entire proposal and 

documentation before combining their comments.

Additionally, the comment period should not close sooner than 90 days after the rule is published 

in the Federal Register and all the documents are put in the docket. This is a significant rule, and 

it warrants and complete and thoughtful input from all the affected parties.

We in our industry have gone to great lengths to try to understand the implications for our 

industry and for consumers in lowering sulfur levels to 10 ppm. As of last week, despite 

requests over the last two-year period, the Agency still hasn’t given us sufficient justification for 

lowering sulfur levels. We’re now facing a forced march to comment based on a pre-publication 

announcement that simply references sources of justification that have just started to be placed in 

the docket.

This absence of information and a truncated comment period basically fly in the face of the 

Administration’s promise to have regulatory transparency. Proceeding in this fashion may even 

be unlawful under the Administrative Procedures Act and the Clean Air Act.

In summary, it’s not reasonable, fair, or lawful for EPA to expect us to come up with an 

intelligible set of comments in such a short period of time to the complicated and incomplete 

regulatory package that EPA has provided. We ask that EPA proceed fairly, lawfully, and issue 

the entire proposal, all the background documents, publish the proposal in the Federal Register, 

and put all the other documents in the docket, and all stakeholders 30 days to prepare for a public 

hearing, and 90 days to enter all their comments.

Commenter: Environmental Defense Fund (EDF)

EPA’s Public Participation Procedures for the Tier 3 Proposal Met All Legal Requirements:

In a letter to EPA dated May 7, 2013, API alleged that the Agency did not follow the Clean Air 

Act’s procedural requirements in proposing Tier 3. As EPA set forth in its May 23, 2013 

response to API, however, the Agency’s Tier 3 procedures met all legal requirements, including 

requirements for publication of the proposed rule in the Federal Register and public participation 

opportunities such as the period for written and oral comments. As EPA noted, the Tier 3 

proposal was prominently posted and available for public review upon signature, on March 29, 

2013. In addition, EPA widely disseminated notice of the proposal’s availability at that time and 

specifically notified stakeholders, including API and the American Fuel & Petrochemical 

Manufacturers. With the extension of the comment period until July 1, 2013, this means that 

commenters have had, as a practical matter, over 90 days to review the proposed rulemaking. In 

addition, EPA provided notice in the Federal Register on April 8, 2013 of the location of the 

docket, the dates for the public hearings, and the duration of the comment period. In summary, 

EDF believes that the Agency met all legal requirements in proposing Tier 3, and strongly urges 

the Agency to move expeditiously to finalize the Tier 3 standards by December 31, 2013. 

Commenter: Union of Concerned Scientists (UCS)
Tier 3 Summary and Analysis of Comments

10-5

Finally, the procedures that EPA followed for the Tier 3 proposal met, and exceeded, all legal 

requirements, including requirements in the Clean Air Act for publication of the proposed rule in 

the Federal Register and public participation activities such as the public comment period and the 

public hearings. The rule was prominently posted and available for public review when it was 

signed on March 29th. With comments due on July 1st, commenters will have had more than 90 

days to comment on the rule, including more than 30 days after the proposal was published in the 

Federal Register. 

Commenter: Flint Hills Resources, LP (FHR)

Proposed Rules for Fuel Used in Flexible-Fuel Vehicles Should Be Published in the Federal 

Register:

EPA’s preamble to the proposed Tier 3 regulations references a separate memorandum (1) that 

includes additional proposed regulations for which EPA seeks comments. These additional 

regulations include prescribing new requirements for E51- E83 for key fuel properties such as 

sulfur, RVP, and benzene. While FHR may support EPA’s effort to develop regulations for E51-

E83, the process EPA used to inform the regulated community runs afoul of the federal 

Administrative Procedures Act (APA) (2) and the federal Clean Air Act (CAA). 

The APA is clear that EPA’s forum for informing the public of substantive rules, amendments, 

and revisions is through the Federal Register (3). Further, the APA states ‘except to the extent 

that a person has actual and timely notice of the terms thereof, a person may not in any manner 

be required to resort to, or be adversely affected by, a matter required to be published in the 

Federal Register and not so published.’

Section 307(d)(3) of the CAA echoes the requirement for proposed rules to be published in the 

Federal Register. Among other things, the notice must ‘specify the period available for public 

comment.’ In addition, at the time of publication, there must be a publicly available docket that 

includes: (1) the factual data on which the proposal is based; (2) an explanation of how EPA 

collected and analyzed the data; and (3) an explanation of the major legal interpretations and 

policy considerations underlying the proposal. 

In the instant matter, EPA describes and seeks comment on very significant potential changes to 

the regulations. EPA is required, by law, to publish such a proposal in the Federal Register. 

Posting on the EPA website or including within the rulemaking docket is not an option —

publication in the Federal Register means publication in the Federal Register. EPA must include 

all proposed changes in the proposed rule. References to documents external to the proposed rule 

do not give the regulated community and public the opportunity to which it is entitled to generate 

informed and timely comments regarding the proposed rule. 

1- Herzog, J. (January 2012). Possible Approach to Fuel Quality Standards for Fuels Used in FlexibleFuel Automotive Spark-Ignition Vehicles (FFVs), Memorandum to the docket. The memorandum is 

referenced in footnote 388 of the pre-publication proposed rule; however, the footnote reference is to a 

memorandum dated January 2012 but the memorandum in the docket is dated April 8, 2013. Further, this 

memorandum was not in the docket at the time the proposed rules were announced on EPA’s website.

2 - United States Code, Title 5, Chapter 5
Chapter 10: Statutory Process and Executive Orders

Our Response:

With regard to the public comment period, EPA met all legal requirements, including 

requirements in the Clean Air Act for publication of the proposed rule and notice of hearings and 

the public comment period in the Federal Register. EPA provided early notice of the Tier 3 

proposal by posting it on EPA’s website upon signature (March 29, 2013), and the docket was 

opened early to allow the public access to materials in the docket. Further, EPA held two public 

hearings for the Tier 3 rulemaking, and also provided an extension of the comment period. All 

of these items were announced in Federal Register notices—and posted on EPA’s website—

going beyond the procedural steps required by law, to promote transparency and public 

participation.

As explained in Section V.H of the preamble to the final rule, we are deferring final action 

on our proposed requirements for E51-83 at this time. We appreciate the valuable input provided 

by commenters and will take this into consideration in our final actions on these standards. We 

will continue to work with stakeholders in developing in-use fuel quality standards for higher 

level ethanol blends. We may issue a supplementary proposal prior to issuing a final rule if the 

additional information we receive from stakeholders warrants such an action.

10.2. Other Executive Orders

Environmental Justice

What Commenters Said:

Commenter: Concerned Citizens Around Murphy

The U.S. Environmental Protection Agency has made good changes to the gasoline we use in our 

vehicles. 

One of the first changes was to mandate unleaded gasoline, which has provided a healthier 

environment for us and our children. Then came low-sulfur gasoline, which also introduced 

ethanol into the product. Then, the EPA required a low-benzene gasoline. The Tier 3 proposal 

will require reductions once again in the sulfur content of gasoline. The reduction of volatile 

organic compounds and sulfur from our vehicles is an important goal to which we should all do 

our part to be part of the solution, but it should not come at the cost of the little good air that is 

left in our neighborhoods around refineries. 

The air quality in fenceline neighborhoods can be so poor at times that residents shelter 

themselves in place or hold their noses when they are on the roads that pass through the refinery 

facilities. 

Clean fuel shouldn’t cost air quality. The EPA should do more to control emissions from the 

refineries that make the lower sulfur content gasoline. Lowering vehicle emissions is important, 

but too much emphasis has been placed on achieving that goal through manufacturing and 
Tier 3 Summary and Analysis of Comments

10-7

refining of lower sulfur content fuels and not enough enforcement and compliance at the 

refineries that make the gasoline. 

EPA’s Tier 3 proposal fails to consider that the reductions at the tailpipe will be offset by the by 

the increased emissions in the neighborhoods around those refineries that do not simultaneously 

install upgraded pollution controls. 

EPA’s Tier 3 proposal fails to consider the increased emissions at the processing plants (the 

refineries). At a recent St Bernard Parish Quality of Life Commission meeting, representatives 

from Louisiana DEQ made a presentation on the non-attainment status for the 2010 sulfur 

dioxide standard. They were asked how the anticipated State SIP for SO2 attainment would 

address Tier 3 mandates. Officials were asked if the refineries lower sulfur in gasoline (for EPA 

Tier 3 mandates), if they take more SO2 out of the gasoline, where will it go? Louisiana DEQ 

responded to assure residents that ‘certainly we will not let it go into the air.” Yet, neither EPA 

nor LDEQ have the authority to require zero sulfur emissions from Tier 3 projects. That sulfur is 

going to go somewhere. That somewhere is our neighborhoods. Whether it happens from 

everyday processing emissions or from switching to a higher content sulfur crude oil or sand oil 

or from emergency flaring or shutdown and startup emissions, the sulfur emissions at the plants 

will offset the reductions at the tailpipes. 

While EPA’s proposed Tier 3 is said to prevent up to 2,400 premature deaths, 23,000 cases of 

childhood respiratory ailments, and 1.8 million lost school days, work days, and days when 

activities would be restricted due to air pollution, the proposal does not account for the health, air 

quality, and quality of life in the refinery fenceline neighborhoods. Those sacrifice zones, areas 

that are overburdened and underserved, where residents are mainly low income people of color, 

will be traded for improvements in other areas that do not have refineries. Air quality in 

fenceline communities will be sacrificed for lower emissions at the tailpipe.

While EPA’s proposed Tier 3 is said to prevent up to 2,400 premature deaths, 23,000 cases of 

childhood respiratory ailments, and 1.8 million lost school days, work days, and days when 

activities would be restricted due to air pollution, the proposal does not account for the health, air 

quality, and quality of life in the refinery fenceline neighborhoods. Those sacrifice zones, areas 

that are overburdened and underserved, where residents are mainly low income people of color, 

will be traded for improvements in other areas that do not have refineries. Air quality in 

fenceline communities will be sacrificed for lower emissions at the tailpipe.

We urge EPA to reconsider how the emissions at the refinery(s) will offset the emissions from 

the tailpipes. We urge EPA to require simultaneous installation of state-of-the-art control 

technology at the refineries that manufacture Tier 3 gasoline products. Our health is depending 

on it.

Commenter: Mercatus Center at George Mason University

While the EPA estimates that that this regulation will have a minimal impact (approximately one 

penny) on fuel costs, others have estimated the impact to be significantly greater, perhaps as 

much as 9 cents per gallon (18). Exactly how much gasoline prices may rise is difficult to say, 
Chapter 10: Statutory Process and Executive Orders

but given that energy costs consume a higher proportion of low-income individuals’ income 

relative to high-income individuals, it is worth acknowledging that this regulation may impose a 

disproportionate impact on low-income individuals. Similarly, recent academic research has 

shown that regulations, such as the proposed regulation, are often more in line with risk 

preferences of wealthy households (19). It is unlikely that poor households are worried about the 

risks posed from PM2.5 and ozone when they face much larger risks elsewhere in their lives. The 

income they lose to comply with this regulation may be better utilized toward other risk 

mitigation. 

18 - David Tamm and Kevin Milburn, “Addendum to Potential Supply and Cost Impacts of Lower Sulfur, 

Lower RVP Gasoline,” (American Petroleum Institute, Houston, TX, March 2012).

19 - Diana Thomas, “Regressive Effects of Regulation.” (Working Paper No. 12-35, Mercatus Center at 

George Mason University, Arlington, VA, November 2012), http://mercatus.org/publication/regressiveeffects-regulation.

Commenter: WE ACT for Environmental Justice

Thank you for the opportunity to provide comments on the proposed Tier 3 Motor Vehicle 

Emission and Fuel Standards. My name is Dr. Jalonne L. White-Newsome and I am a federal 

policy analyst with WE ACT for Environmental Justice, a 25-year old environmental justice 

organization with offices in Harlem, New York and Washington, DC. WE ACT’s mission is to 

build healthy communities by assuring that people of color and/or low income participate 

meaningfully in the creation of sound and fair environmental health and protection policies and 

practices. The inception of our organization, in fact, was fueled by the battle for clean, healthy 

air in Northern Manhattan. In an effort to protect and address the health concerns related to air 

emissions from a sewage treatment plant that was plopped into the Harlem community, as well 

as the 6 diesel bus depots, 4 garbage truck depots and many other sources of pollution...WE ACT 

continues to educate, engage community residents, academic and health partners to demand that 

the protection of human health and welfare be afforded to all – despite the hue of your skin, the 

amount of money and resources in your pockets, and the zip code you happen to live in. Since 

1988, we have had the opportunity to be that voice, not only in Harlem, but on the national stage 

to help influence the conversation around several domains of environmental work, with clean air 

always being a priority concern. 

I’m sure you know that the residents of Harlem, NY and many other similar cities and towns 

across our great nation are not breathing the same air – some of clean, and some is pretty dirty. 

So as many organizations across the country are wrapping up their Earth Day celebrations, just 

yesterday, I was reminded of why we do the work we do. 

I went to pick up my 4 and 6 year old from school yesterday, going through the usual motions of 

signing out my girls, saying HI to other Moms and Dads, when I noticed something different this 

time. As I peered behind the secretary’s desk, a cute little girl, with two little pig-tails and 

beautiful bright eyes, caught my attention – first because she reminded me of my little one, but, 

more importantly in addition to her school uniform, she was wearing a breathing mask, 

connected to a small machine, receiving a breathing treatment. I think the secretary saw me 

looking with a concerned look on my face and I gave the little girl a slight smile. I walked to my 

car, thinking about this young lady, and the many other children that I know that have to receive 
Tier 3 Summary and Analysis of Comments

10-9

breathing treatments, or take medications, miss school, etc. to survive and try and live a kid’s 

life. Due to no fault of their own – other than playing outside, going to school and living – their 

quality of life is compromised because of the state of the air they breathe. A child. 

And then I thought about some of the senior citizens I have worked with, specifically in Detroit, 

Michigan, a part of Wayne County and one of the areas discussed in the rule documentation and 

I thought about my great Aunt, who is in her mid-80s that suffers with severe asthma, constantly 

having to be hospitalized because she has lived the majority of her life in various neighborhoods 

in Detroit, my hometown – unfortunately in areas that continue to be overwhelmed with multiple 

social stressors – crime, poverty, etc. – but also air toxins from both stationary and mobile 

sources that continue to negatively impact her health status.

You know, cumulative risk assessment or cumulative impact assessment, however you want to 

phrase it, is a way of understanding the real and total impacts on communities. We know that 

environmental pollution doesn’t act in silos, and that’s what we really need to consider as we 

look at these different rules.

When you look at EJ communities, they’re hot spots. They’re areas where there’s a lot of things 

going on, and most of the time the rules and the things that we use to frame these rules don’t 

capture everything that’s happening. And so, what I would suggest is that, I guess, really offer a 

competent suggestion is that keep in mind that having these more stringent standards will work 

towards minimizing the burden on communities that are already compromised.

So if we focus on really the most vulnerable, I truly believe that more people will benefit overall, 

and having the rules, like the soot rule, Tier 3, and others, work in parallel is great. And so my 

suggestion, however, is that in future analyses, a cumulative impact strategy be employed.

I know that several of your colleagues in the EPA are working towards this as well as developing 

an environmental justice guidance that will be incorporated throughout the Agency. But I hope 

that this is something that you will strongly consider in future assessments to make sure that we 

get a real glimpse of the impacts and the benefits that come from these proposed rules.

I’m sure you are aware of the Urban Air Toxics report that is supposed to be prepared for 

Congress per Section 112(k) of the Clean Air Act. Briefly, the purpose of this report was to 

provide an update on the strategies taken on by the EPA to address the cumulative health risks in 

urban areas, specifically around urban toxics. Unfortunately, the first report was issued back in 

2000 but there has not been an update since then. From what I have heard, the EPA is working 

on getting this report out in the near future. I bring this report up because the Tier 3 rules 

proposed will work to address – over time – some of the air toxins identified in the urban air 

toxics strategy. It is so critical that we can document the levels of air toxins in our urban 

neighborhoods, but also quantify the health impacts of potential carcinogens in our EJ 

communities. Having the data is the only way we can understand the present levels in our most 

compromised communities, and evaluate, over time, if the variety of programs and other 

mitigation efforts are actually working. So I hope, that in addition to these proposed standards, 

that the proper and adequate monitoring of our roadways, as well as refining the specificity of 

urban air toxics monitoring and urban communities will be an issue that is addressed, so we can 
Chapter 10: Statutory Process and Executive Orders

truly understand the exposure and, hopefully, the decrease in urban air toxins in the communities 

that are already disproportionately impacted. 

Urban air toxics are a significant factor in cumulative risk assessment or ‘Cumulative impacts’ as 

those in the environmental justice community like to capture this ideal. Because pollution –

whether it be air, waste, water - does not act in a silo. Consequently, we believe that in order to 

properly characterize and environmental justice community, the SUM of the exposures must be 

considered – together, and not just individual pollutants. I do believe that the word ‘cumulative 

impacts’ was mentioned in the proposed rule. And I simply want to offer a comment and 

suggestion. Keep in mind that the more stringent standards will work towards minimizing that 

burden on communities that are already compromised. So, if we can focus on making life better 

for the “most vulnerable”, I truly believe that more people will benefit, overall. Having the rules 

– soot rule, Tier 3 and others – work in parallel is great. My suggestion, however, is that in future 

analysis, a cumulative impacts strategy is employed. I know several of your colleagues are 

working to develop environmental justice guidance as well as guidance for preparing a 

cumulative risk assessment strategy so I would encourage you to potentially look into that work 

and how it can be integrated this time or in the next iteration of proposed rules. 

Our Response:

Regarding the Mercatus Center comment, please see Chapter 9.2 of this Summary and 

Analysis of Comments document.

Regarding the comments from Concerned Citizens Around Murphy, please see Chapter

3.3.1 of this Summary and Analysis of Comments document.

Regarding WE ACT for Environmental Justice’s comments, we acknowledge the 

concerns expressed and agree that these standards will help to reduce the burden on communities 

affected by multiple stressors. While the air quality improvements associated with this final rule 

affect the nation as a whole, locations in close proximity to major roadways will experience the 

most direct changes in a way that reduces their exposures. With regard to the comment urging 

analysis of cumulative impacts, EPA notes that the quantitative air quality analyses used to 

evaluate the health impacts of this rule include multiple air pollutants, including PM2.5, ozone, 

and air toxics. Furthermore, the RIA reviews available literature on the health effects associated 

with living or attending school in close proximity of traffic. In describing how this rule affects 

environmental justice, the RIA summarizes studies that evaluate the cumulative impacts of air 

pollution and social stressors such as neighborhood violence. EPA agrees that consideration of 

the full range of impacts of the rule is important. We acknowledge the comments concerning 

updating the Urban Air Toxics report and urging proper monitoring of air quality, but they are 

beyond the scope of this rulemaking.

10.3. Comment Period

What Commenters Said:
Tier 3 Summary and Analysis of Comments

10-11

Commenter: American Fuel & Petrochemical Manufacturers (AFPM)

As you know, the Agency released a proposal for Tier 3 motor vehicle and fuel standards on 

March 29, 2013. This proposal has not yet been published in the Federal Register.

In a hearing notice published in the Federal Register on April 8, 2013, EPA announced that the 

public comment period would end on June 13, 2013. The length of this comment period is 

inadequate for a broad technical rulemaking such as this, especially one that includes diverse 

topics of vehicle emissions standards, fuel standards and the distinct unrelated issue of 

Performance Based Measurement System. Each of these issues requires different technical 

expertise to analyze.

The docket was opened on April 15. There are over 600 documents now in the Tier 3 docket in 

the Supporting and Related Material category. It is virtually impossible to review and analyze 

this volume of supporting technical information in the time allotted for public comment. 

Accordingly, we request additional time to prepare informed comments on the proposal.

AFPM requests that the public comment period be extended to 90 days after publication of the 

proposal in the Federal Register.

The AFPM has requested that the public comment period for the Tier 3 rulemaking be extended 

beyond June 13. There are hundreds of documents in the docket, and additional time is 

necessary for a comprehensive review. AFPM recommends 90 days after publication of this 

proposal in the Federal Register.

Commenter: Institute for Energy Research (IER)

The Institute for Energy Research is deeply concerned about EPA’s proposed Tier 3 rulemaking. 

The public comment period deadline has been set for June 13th, and yet EPA only published the 

proposed rule in the Federal Register on May 21st. This allows the public less than a month’s 

time examine the significant economic implications of the rule. Moreover, questions remain 

about the data used by EPA to derive the costs and benefits of the Tier 3 proposal, and the rule 

has also included several non-germane regulations such as the E15 certification fuel. Given these 

complexities and unanswered questions, we request at least a 90-day extension for the comment 

period.

Closing the public comment period on June 13, 2013 is likely in violation of the Clean Air Act 

that requires “notice of proposed rulemaking shall be published in the Federal Register” and that 

“[the Administrator] shall ensure a reasonable period for public participation of at least 30 days.” 

The abbreviated period of 24 days does not give the American people sufficient time to comment 

on this complex and expensive regulation, which will impact each and every American.

Third, the impact of Tier 3 will be widespread and detrimental to the U.S. economy, and as such, 

the rule warrants greater consideration. A study by Baker & O’Brien Inc., prepared for the 

American Petroleum Institute, estimated that Tier 3 would impose initial compliance costs to oil 

refineries of $9.7 billion dollars. The ongoing costs associated with this rule would also increase 
Chapter 10: Statutory Process and Executive Orders

the price paid for gasoline at the pump by 6–9 cents per gallon, which does not capture what the 

full “ripple effect” would be on the greater economy (6). Given the large costs, and the fact that 

EPA has failed to conduct whole-economy modeling for the rule, an extension of 90 days does 

not seem unreasonable.

We appreciate EPA’s concern and actions to ensure legal and transparent public participation in 

the rulemaking process. Strict legal compliance with rulemaking procedures as outlined in the 

Clean Air Act will ensure this rule is fully evaluated and given proper consideration by all 

concerned parties in an effort to identify and craft legislation that best serves the public interest 

of this country. It is therefore critical that EPA extend the comment period and release all of the 

data upon which it relies. Such an action would be in keeping with the President’s pledge to 

foster openness and transparency in the workings of the federal government, particularly when 

they affect the public so profoundly.

6 - Tamm, David C. and Milburn, Kevin P. (2012) Addendum to Potential Supply and Cost Impacts of 

Lower Sulfur, Lower RVP Gasoline. Houston, TX. Retrieved May 17th, 2013 from http://api.org/newsand-media/news/newsitems/2012/mar-2012/~/media/Files/News/2012/12-March/Addendum-PotentialImpacts-of-Lower-Sulfur-Lower-RVP-Gasoline-Report.ashx

Commenter: National Propane Gas Association (NPGA)

NPGA urges the Agency to extend the comment period beyond the stated June 13, 2013 

deadline.

The current 23 day comment period (based on the May 21, 2013 publication in the Federal 

Register) simply does not grant adequate time to complete a detailed analysis of this complex, 

377-page proposed rule. The additional time is needed to develop the substantive comments 

sought by EPA.

NPGA believes a 60-day comment period should be established, based on the Federal Register 

publication date, which is standard for a proposal of this complexity. This would extend the 

deadline to July 21, 2013, and NPGA strongly urges EPA to take the action of extending the 

comment period.

Our Response:

EPA’s procedures for the Tier 3 rulemaking have met and exceeded all legal 

requirements, including requirements in the Clean Air Act for publication of the proposed rule in 

the Federal Register and opportunities for public participation. In addition to holding two public 

hearings on the proposed rule, we provided early public notice of the proposal (prominently 

posted on EPA’s website and available for public review immediately after signature on March 

29, 2013) as well as early public access to the Tier 3 rulemaking docket.

In response to requests, we also extended the comment deadline from June 13, as 

originally set, to July 1, 2013 to provide the public with more time to prepare and submit 

comments. With the extension, we provided over 90 days to review and submit comments on the 
Tier 3 Summary and Analysis of Comments

10-13

proposed rule, including more than 30 days after the May 21, 2013 publication of the proposed 

rule in the Federal Register. We concluded that the extension to July 1 was sufficient in light of 

the time period provided to review and submit comments on the proposal. We were also mindful 

that additional delay could affect the timely finalization and implementation of the Tier 3 

program and its close harmonization with the California LEV III program, the need to provide 

adequate compliance lead time for regulated parties, and the importance of assisting states by 

achieving emission reductions to help attain and maintain the existing National Ambient Air 

Quality Standards (NAAQS).

We continue to believe that these actions complied with and went beyond the procedural 

steps required by law, to promote transparency and public participation in the Tier 3 rulemaking. 
Tier 3 Summary and Analysis of Comments

11-1

11. Comments on Proposed Regulatory Text

What We Proposed:

The comments in this chapter correspond to the proposed regulations, and are specific 

edits to the regulatory text that were suggested by commenters. As described below, many of 

these regulatory comments (such as those that were editorial or otherwise very specific) do not 

fit well within the structure of this document and are addressed elsewhere. This is because the 

majority of the comments received on this rule were comments on the proposed policy rather 

than the proposed regulatory text. Thus, the other chapters of this Summary and Analysis of 

Comments document were structured to address such policy comments rather than the type of 

comments addressed by this Chapter. While summaries of the regulatory comments received 

and our responses to those comments are discussed briefly below, readers are referred to other 

documents in the public docket for this rulemaking for a more complete analysis of these 

comments.

11.1. Engine and Vehicle Testing Regulations (40 CFR Parts 86, 1065, and 1066)

What Commenters Said:

We received detailed comments from manufacturers and the State of California on the 

regulatory text describing the test procedures. These comments and our responses to them have 

been summarized in detail in 5 memoranda to the docket,1and are not repeated here. The 

comments addressed issues such as temperature tolerances for testing, design specifications for 

laboratory cooling fans, and preconditioning sample systems prior to testing, along with dozens 

of similar comments.

Commenters:

Alliance of Automobile Manufacturers (Alliance) and Association of Global Automakers 

(Global)

BMW

California Air Resources Board (CARB)

Emissions Control Technology Association (ECTA)

Manufacturers of Emission Controls Association (MECA)

Truck and Engine Manufacturers Association (EMA)

Volkswagen Group of America, Inc.

Volvo Car Group

11.2. Fuels Regulations (40 CFR Parts 78 and 80)

What Commenters Said:

 

1 EPA-HQ-OAR-2011-0135.
Chapter 11: Comments on Proposed Regulatory Text

11-2

We received comments from several parties in the fuel industry with detailed edits on the 

proposed regulatory text in 40 CFR parts 79 and 80. These edits, which are not repeated or 

summarized here, addressed various areas of the regulations including suggested changes to 

definitions, deadlines, and additions/deletion of text to add clarity to the regulations.

Commenters:

American Petroleum Institute (API) and the Association of Fuel & Petrochemical Manufacturers 

(AFPM)

Chevron Products Company

Growth Energy

Magellan Midstream Partners, L.P.

Marathon Petroleum Company LP (MPC)

POET, LLC

Renewable Fuels Association (RFA)

Shell Oil Products for Shell and Motiva

Weaver and Tidwell LLP

Our Response:

We have responded to some of the issues raised by the edits to the fuel-related regulatory 

text in Chapters 5.3, 5.5, 5.6, and 6.1 of this Summary and Analysis of Comments document. 

Further, we have made changes to the regulations, where appropriate, based on these suggested 

edits or new information received. A summary of our responses to these comments is contained 

in a memorandum to the docket entitled “Summary of Responses to Comments Regarding 

Detailed Edits of the Proposed Fuel Regulations in the Tier 3 NPRM”.
Tier 3 Summary and Analysis of Comments

12-1

12. Comments Unrelated to the Proposed Rule

What We Proposed:

The comments in this chapter do not necessarily correspond to a specific section of the 

preamble to the proposed rule, but rather are comments that span various areas and issues. A 

summary of the comments received and our responses to those comments are located below.

12.1. Boutique Fuels

Organizations: National Association of Clean Air Agencies (NACAA)

Mid-Atlantic Regional Air Management Association Inc. (MARAMA)

When promulgating this final rule, EPA should provide a clear path forward for state and local 

agencies with respect to transitioning from current boutique fuel programs to the federal Tier 3 

program including a streamlined SIP process and related guidance. 

Our Response:

This comment appears to request that the Agency work with them to develop a 

streamlined process whereby States may end their current State-run fuel programs without 

interfering with their SIP compliance. The commenters appear to believe that the emission 

reductions resulting from Tier 3 may obviate the need for their existing “boutique fuel programs” 

which are almost all State or Local RVP control standards. The EPA would be willing to 

discuss options for doing so, but this comment is otherwise outside the scope of this rulemaking.

12.2. Comments Related to the Renewable Fuels Standard

What Commenters Said:

Commenter: Pennsylvania Department of Environmental Protection (DEP)

The EPA should explore opportunities and implement program changes for relieving the burden 

placed on refiners to meet the Tier 3 requirements. 

A practical way to relieve the burden on refiners to meet the Tier 3 standards would be for EPA 

to reduce or stop increasing the national quota for biofuel production. The EPA sets this 

increasing biofuel mandate or Renewable Portfolio Standard which costs refiners resources that 

refiners could use to meet the Tier 3 standards. While reduced sulfur in gasoline, which will 

occur as a result of Tier 3, allows for better catalytic converter performance for reducing NOx 

emissions, the annually increasing Renewable Fuel Portfolio standard, which relies heavily on 

ethanol use, increases NOx emissions from automobiles. Given the huge health benefits 

associated with lowering NOx emissions and ozone levels as stated in this proposed rulemaking, 
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12-2

ail EPA priority should be to reduce NOx emissions from all programs, and correspondingly, 

ozone levels across the nation. 

Commenter: Clean Fuels Development Coalition (CFDC)

We also applaud EPA for recognizing its key role in the implementation of the federal 

Renewable Fuel Standard. EPA identified in its Regulatory Impact Analysis that accompanied 

the final rule governing the RFS, there are substantial benefits that can result from full 

implementation of the RFS and specific and quantifiable positive health impacts. Because of our 

broad base of membership and interests as well as our longevity in working on these issues, both 

our organizations regularly communicate with other stakeholders and like-minded organizations.

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

RFS2 Q&A 7.8 (diesel blendstock RVO issue) (44) suggests that any diesel blendstock or 

heating oil that meets the qualities of MVNRLM diesel should be included in an obligated party's 

obligated volume. This is in direct contradiction to § 80.1407 (e) and (f), in Preamble II F 2 (75 

FR 14720 and 14721) which state that diesel fuel that is designated as heating oil, jet fuel, or any 

designation other than MVNRLM or a subcategory of MVNRLM will not be subject to the 

applicable percentage standard and will not be used to calculate the RVOs. EPA should strike 

RFS2 Q&A 7.8 (diesel blendstock RVO issue).

The regulations specify that when a refiner designates gasoline or diesel which it produces, for 

export, there is a commensurate reduction in that refiner’s RFS RVO. This limitation will likely 

result in obligated parties having to purchase RINs for exported gasoline and diesel since it often 

happens that the party that designates product for export will be other than the refiner of that 

product. EPA should allow any obligated party that “designated for export” gasoline or diesel to 

reduce their RVO regardless of whether that product was so designated when it was produced. 

Likewise, a company that changes the use of a fuel “designated for export” to domestic use 

would incur a RVO obligation for the volume that the use designation was changed. This ensures 

industry wide volume obligations are properly accounted for and attainable. This system allows a 

refiner to claim the RVO benefit without unnecessary tracking by designating product for export. 

It also ensures appropriate accounting for fuels designated for export that are later used 

domestically.

Our Response:

These comments are related to specific elements of the RFS program, and are thus 

outside of the scope of the Tier 3 program.

The issue involving exports and RVOs is outside the scope of this proposed rulemaking.

However, it was initially addressed in the RFS Renewable Identification Number (RIN) Quality 

Assurance Program proposed rule (78 FR 12158 (February 21, 2013)). It will be fully addressed 

in the final rule for the RIN Quality Assurance Program which is expected to be finalized in the 

coming months.
Tier 3 Summary and Analysis of Comments

12-3

12.3. Vapor Pressure Reduction of In-Use Fuels

What Commenters Said:

Commenter: Ford Motor Company (Ford)

Meeting the more stringent evaporative emissions standards of Tier 3 is made possible through 

the promotion of the “fuels and vehicle are a system” messaging communicated in the Tier 3 

NPRM. The reduction in market fuel vapor pressure affects the entire fleet of vehicles on the 

road, giving benefits immediately after introduction of the new fuel. Additionally, any gasoline 

powered off-road vehicle or machinery would also immediately benefit from reduced 

evaporative emissions due to an appropriate reduction in vapor pressure.

Our Response:

A reduction in the vapor pressure of in-use fuels as discussed by the commenter was not 

part of the proposed or final Tier 3 evaporative emission standards. 

12.4. Comments Related to Ethanol and Aromatics Control

What Commenters Said:

Commenter: POET, LLC

As noted above, ethanol cost-effectively provides a high-octane, clean-burning fuel that is 

important for meeting recently-tightened CAFE and EPA greenhouse gas emissions standards. 

Ethanol, including from cellulosic and other next generation biofuel sources, can dramatically 

reduce GHG emissions and even further increase the environmental benefits of ethanol. In 2012 

renewable fuel use reduced greenhouse gas emissions by over 33 million metric tons. (9) 

Furthermore, EPA estimates that by 2022, the RFS will reduce greenhouse gas emissions by 138 

million metric tons or the equivalent of taking 27 million passenger vehicles off the road. (10) 

Numerous companies, including POET and DSM, have made significant investments in 

cellulosic ethanol production that can provide particularly significant greenhouse gas reductions. 

(11) 

Regarding emissions, clean-burning ethanol is key to Tier 3 emission reduction goals for sulfur 

and particulate matter, two pollutants around which the Tier 3 rule is anchored. Ethanol contains 

sulfur in de minimis amounts, so increasing ethanol blends in gasoline can help bring about the 

sulfur-related benefits that Tier 3 seeks to accomplish. Ethanol can also reduce highly harmful 

particulate matter emissions, particularly in next-generation engines. (5) 

Clean burning ethanol is also critical to reducing air toxics, a subset of particularly harmful 

substances. The Clean Air Act fuel ‘air toxics’ regulations in Section 202(1) specifically identify 
Chapter 12: Comments Unrelated to the Tier 3 Rulemaking

12-4

three pollutants including benzene, 1,3 butadiene, and formaldehyde, and Section 211(k)(10) 

further identifies as ‘toxic air pollutants’ polycyclic organic matter (which includes polycyclic 

aromatic hydrocarbons known as PAHs), and acetaldehyde. In contrast to gasoline, ethanol does 

not contain benzene, a key air toxic. Increased ethanol use can also reduce PAHs (6) and 1,3-

butadiene. (7) The Harvard Center for Risk Analysis has found that gasoline aromatic 

hydrocarbons, including benzene, lead to ‘approximately 3800 predicted premature mortalities 

nationwide.’ (8) Clean-burning ethanol provides a ready means of reducing toxic aromatics, 

including benzene and others. 

Oddly, EPA in the Proposed Rule mischaracterizes (without clear explanation) ethanol as an air 

toxic; EPA must avoid this mischaracterization. As noted above, ethanol is not listed as one of 

the specifically enumerated air toxics of concern in Sections 202(1) or 211(k)(10). Furthermore, 

the Agency did not include ethanol among the 177 air toxics compounds that were evaluated in 

the most recent National-Scale Air Toxics Assessment. (12) Nor does the Proposed Rule provide 

any reasoned grounds for its passing reference to ethanol as an air toxic.

It should also be recognized that the Tier 3 rule and the RFS are mutually-reinforcing. In 

particular, EPA recognizes that the RFS ‘will result in significant amounts of ethanol-blended 

gasoline in the implementation timeframe of the proposed Tier 3 program.’ (18) Ethanol can help 

to obtain Tier 3’s emissions reduction goals, while a properly-designed Tier 3 rulemaking can 

help to provide a market for, and enable the deployment of, clean-burning biofuels to ensure that 

Congress’ biofuels use targets in the RFS are met. 

In summary, clean-burning ethanol is key to Tier 3 emission reduction goals for sulfur, 

particulate matter, air toxics, and other key pollutants, and improves our nation’s economy and 

energy security. However, to achieve these emissions reductions, appropriate regulations are 

necessary for the widespread use of low-emitting, domestically-sourced biofuels. 

5 - See e.g., M. Maricq et al., The Impact of Ethanol Fuel Blends on PM emissions from a Light-Duty 

GDI Vehicle, 46 Aerosol Science & Technology 576 (January 2012), available at 

http://www.tandfonline.com/doi/pdf/10.1080/02786826.2011.648780; see also, Robert A. Stein et al., An 

Overview of the Effects of Ethanol-Gasoline Blends on SI Engine Performance, Fuel Efficiency, and 

Emissions, AVL Powertrain Engineering Inc. and Ford Motor Company (April 8, 2013), regarding the 

ability of increased ethanol blends to improve engine efficiency and reduce a variety of pollutants, 

including particulate matter.

6 - See, e.g., M.A. Costagliola et al., Combustion efficiency and engine out emissions of a S.I. engine 

fueled with alcohol/gasoline blends, Applied Energy (2012), available at 

http://www.sciencedirect.comjscience/article/pii/S0306261912006836.

7 - While ethanol may increase emissions of acetaldehyde and formaldehyde, due to the much higher 

toxicity weighting of benzene and 1,3-butadiene, ethanol nevertheless results in significant health benefits 

due to reductions in these pollutants. See Stein et al., An Overview of the Effects of Ethanol-Gasoline 

Blends on SI Engine Performance, Fuel Efficiency, and Emissions, supra.

8 - See Katherine von Stackelberg, et al., Public health impacts of secondary particulate formation from 

aromatic hydrocarbons in gasoline, 12 Environmental Health 19 (February 20, 2013), available at 

http://www.ehjournal.net/content/12/1/19 -/abstract.

9 - Renewable Fuels Association, Battling for the Barrel: 2013 Ethanol Industry Outlook (February 

2013), p.18, available at http://ethanolrfa.org/page/-/PDFs/2013%2ORFA%200utlook.pdf?nocdn=1.
Tier 3 Summary and Analysis of Comments

12-5

10 - EPA final rule, Regulation of Fuels and Fuel Additives: Changes to Renewable Fuel Standard 

Program, 75 Fed. Reg. 14,670, 14,683 (March 26, 2010).

11 - POET-DSM’s first commercial ethanol production facility, slated to begin operating in early 2014, 

has been predicted by a third-party analysis to reduce GHGs by 111% compared to gasoline—i.e., the 

cellulosic ethanol will more than offset the GHG emissions of gasoline. See Air, Inc., Lifecycle 

Emissions of POET’s LIBERTY Cellulosic Ethanol Plant, available at http://poet.com/media/LCA-execsummary.pdf. These significant GHG reductions are achieved by eliminating the need for fossil fuel both 

at the cellulosic plant and at an adjacent, grain-based ethanol facility.

12 - See, e.g., the list of Air Toxics in the 2005 NATA Assessment released March 11, 2011, available at 

http://www.epa.govittn/atwinata2005.

18 - 78 Fed. Reg. 29,820.

Commenter: American Coalition for Ethanol (ACE)

The combination of the Renewable Fuel Standard (RFS), 2017-2025 GHG/CAFE standards, and 

Tier 3 proposal by EPA make up the best option for substantially further reducing GHG 

emissions from the transportation sector because collectively these programs will result in the 

use of higher blends of ethanol. These higher ethanol blends will replace the marginal gallon of 

petroleum (that has significantly higher GHG emissions) and are much more practical in the near 

term than electric cars (powered by coal and natural gas) and LNG vehicles that also have 

significant infrastructure issues. Taken in combination, the RFS and proposed Tier 3 standards 

should help signal to oil companies and automakers that future vehicle technologies will need to 

be capable of taking advantage of ethanol’s clean octane and the many other benefits that 

ethanol-blended fuels have to offer. 

ACE believes it is proper for EPA to use the Tier 3 rule to limit sulfur and harmful gasolinebased aromatics and for public health reasons, but we also take this opportunity to encourage the 

Agency to address other public health concerns stemming from petroleum as well. 

First, EPA needs to revisit its models with respect to data on emissions from today’s petroleum. 

We encourage the Agency to place a priority on making certain that the Community Multiscale 

Air Quality (CMAQ) model recognizes the dominant role gasoline aromatics play in urban 

particulate matter (PM2.5) secondary aerosol (SOA) emissions. A recent Harvard study confirms 

that EPA’s models under-predict SOA emissions by at least a factor of two to four times, and 

that they are responsible for tens of billions of dollars worth of avoidable public health impacts.2 

Second, EPA should be more transparent about the air and water pollution health risks from 

highly toxic polycyclic aromatic hydrocarbons (PAHs), which the Agency acknowledges in its 

regulatory impact analysis, but for some reason does not currently regulate for mobile sources. 

Recent studies by automakers show that midlevel blends of ethanol (such as E30) are able to 

reduce these particle-borne PAH emissions by 45 — 60 percent or more, and we encourage the 

Agency to include these findings in the final rule.3 

Finally, it is critically important that EPA recognize it unfairly penalizes ethanol’s field-to-wheel 

carbon footprint. We encourage the Agency to correct deficiencies in the GHG rule regarding 

ethanol’s significantly smaller carbon footprint compared to gasoline. Doing so would help 

provide more sufficient incentives for automakers to manufacture additional FFVs and future 
Chapter 12: Comments Unrelated to the Tier 3 Rulemaking

12-6

vehicle technologies which can take greater advantage of the high and clean octane benefits of 

midlevel ethanol blends.

Fully valuing the impacts of petroleum and advantages of higher ethanol blends as discussed 

above will significantly underscore the benefit in EPA’s implementation of Tier 3, CAFE-GHG, 

and the RFS and further motivate more rapid expansion of higher octane ethanol blends in the 

United States. 

2 Katherine von Stackelberg, et al., 12 Public Health Impacts of Secondary Particulate Formation from 

Aromatic Hydrocarbons in Gasoline, Environmental Health (2013), available at

http://www.ehjournal.net/content/12/1/19.

3

See Koichiro Aikawa, et al., Development of a Predictive Model for Gasoline Vehicle Particulate Matter 

Emissions, SAE International (Oct. 25, 2010); M.A. Costagliola, et al., Combustion Efficiency and 

Engine Out Emissions of a S.I. Engine Fueled with Alcohol/Gasoline Blends, Applied Energy (2012); M. 

Matti Maricq, et al., The Impact of Ethanol Fuel Blends on PM Emissions from a Light-Duty GDI 

Vehicle, 4 6 Aerosol Sci. & Tech. 57 (2012).

Commenter: American Council on Renewable Energy (ACORE)

There is a major policy option that will significantly reduce our dependence on oil, and improve 

the nation’s health and economy. In Section 202 of the 1990 Clean Air Act Amendments, EPA 

was required to reduce aromatics in gasoline to the maximum extent possible. EPA designed 

questionable models (and still relies on these out-of-date computer models). Consequently the 

EPA determined the most cost-effective approach, and then established a 25% ceiling on 

benzene, toluene, and xylene and continues to reduce the benzene level, with little mention of 

other chemicals in the aromatics group. It soon became clear that aromatic levels could be 

appreciably lowered, providing important economic and human health benefits; and at the same 

time boosting the market share in the light-duty transportation sector for sustainable alcohols. 

But, EPA has not taken action, even though there is a plethora of information to fully justify this 

action. This information is available to the Committee, and in some cases has already been or 

being supplied by several forces, specifically now in the Coalition/Urban Air Initiative 

(EFC/UAI) comments. 

Commenter: Clean Fuels Development Coalition (CFDC)

In particular we had an opportunity to review and contribute to comments submitted to you on 

this Rule by the Urban Air Initiative and the Energy Future Coalition. CFDC and 25 x 25 have 

been studying the impacts of aromatic hydrocarbons for several years now and completely agree 

with the UAI/EFC comments with regard to calling on EPA to recognize and quantify the public 

health benefits that can be achieved by reducing toxic aromatic compounds in gasoline. The UAI 

comments and supporting documentation does, in our view provide an excellent case for 

reducing the use of aromatics in transportation fuels and importantly ties it to numerous other 

public policy initiatives EPA is grappling with ranging from overall CO2 greenhouse gas 

emissions to black carbon and particulates. Therefore, we urge EPA to focus on the UAII/EFC 

comments as they are representative of the views of our organizations as well. 
Tier 3 Summary and Analysis of Comments

12-7

The other huge impediment to getting more high-ethanol capable vehicles on the road was 

created through the Corporate Average Fuel Economy/Greenhouse Gas Rule last year. In that 

Rule vehicles operating on blends even as high 85% receive a paltry 1% GHG Credit due to 

outdated and inaccurate modeling. We believe ethanol’s GHG advantages over petroleum are 

severely under estimated and when combined with some of these other initiatives could provide a 

pathway to increased biofuel use, successfully implementing the RFS. 

Commenter: E.I. du Pont de Nemours and Company

In enacting the RFS, the Congress set a forward looking 15-year policy intended to incent the 

large scale development of renewable fuels in the U.S. It succeeded ahead of schedule for grain 

ethanol, and has to date met its overall volume targets successfully. The existing suite of biofuels 

policies, of which the RFS is a significant component, has been very successful in standing up a 

U.S. biofuels industry that is making a material contribution to U.S. energy security and reducing 

the environmental footprint of transportation. 

Specifically, biofuels have made significant contributions to reducing GHG emissions but also 

provide a low sulfur, aromatic-free, olefin-free gasoline volume which assists in meeting criteria 

pollutant goals. 

We have to remember that we started down the road of alternative transportation fuels because of 

the variety of security, environmental and economic ramifications of our dependence on 

petroleum. Those challenges have only grown more acute and we are making solid progress. 

Today, biofuels production in the U.S. offsets over 10 billion gallons of petroleum demand each 

year. 

Commenter: Energy Future Coalition and Urban Air Initiative 

Air quality and public health: Aromatic hydrocarbons—which are air toxics in their own right—

make up approximately 20%-30% of standard motor vehicle fuel in the United States. On 

combustion, these compounds produce emissions of benzene, toluene, ethylbenzene, xylene, 1,3-

butadiene, polycyclic aromatic hydrocarbons (PAHs), and a host of other hazardous air 

pollutants, including dangerous levels of fine and ultra-fine particulate matter (PM2.5 and 

UFPs). Ethanol is a substitute for octane-enhancing aromatics; the average aromatics content in 

gasoline has dropped 16 percent over the past decade due to ethanol blending. (2) 

PM2.5 is widely viewed as the most lethal air pollutant in the United States. It causes thousands 

of deaths every year, as well as a range of other health and environmental effects. (54) As EPA 

noted in its 2007 MSAT rule, “[h]ealth effects associated with short-term exposures (e.g., hours 

to days) in ambient PM2.5 include mortality, increased hospital admissions, heart and lung 

diseases, increased cough, adverse lower-respiratory symptoms, decrements in lung function and 

changes in heart rate rhythm and other cardiac effects.” (55) Studies also show associations 

between long-term exposure to PM2.5 and cardiorespiratory and lung-cancer mortality. (56)

54 - See C. Arden Pope III, Epidemiology of Fine Particulate Air Pollution and Human Health: Biologic 

Mechanisms and Who’s at Risk?, 108 Environ. Health Perspectives Supplements (2000); Pope, et al., 
Chapter 12: Comments Unrelated to the Tier 3 Rulemaking

12-8

Lung Cancer, Cardiopulmonary Mortality, and Long-term Exposure to Fine Particulate Air Pollution, 287 

JAMA 1132 (2002), available at http://www.epw.senate.gov/107th/Levy_1.pdf. 

55 - 2007 MSAT Rule, 72 Fed. Reg. at 8443; accord Regulation of Fuels and Fuel Additives: Changes to 

Renewable Fuel Standard Program, 75 Fed. Reg. 14670, 14808-09 (March 26, 2010) [hereinafter 

“RFS2”] (“Health effects associated with short-term exposures (hours to days) to ambient PM include 

premature mortality, aggravation of cardiovascular and lung disease (as indicated by increased hospital 

admissions and emergency department visits), increased respiratory symptoms including cough and 

difficulty breathing, decrements in lung function, altered heart rate rhythm, and other more subtle changes 

in blood markers related to cardiovascular health.”). 

56 - See RFS2, 75 Fed. Reg. at 14808-09 (“Long-term exposure to PM2.5 and sulfates has also been 

associated with mortality from cardiopulmonary disease and lung cancer, and effects on the respiratory 

system such as reduced lung function growth or development of respiratory disease. A new analysis 

shows an association between long-term PM2.5 exposure and a subclinical measure of atherosclerosis.”).

A recent study led by the Harvard Center for Risk Analysis, with participation by EPA, 

estimated the public health impacts from exposure to only one of these hazards—PM2.5 

originating from aromatic hydrocarbons in gasoline—at approximately 3800 premature 

mortalities nationwide and total social costs of $28.2 billion. (3) A straight-line extrapolation of 

aromatics reduction from ethanol replacement suggests that a 30% ethanol blend would save on 

the order of $9 billion annually for just this one of many public health benefits—more than the 

low end of the total monetized health benefits of the Proposed Rule. (4) Of particular concern, 

emission reduction technology in newer vehicles may worsen PM2.5 pollution if aromatics are 

not reduced in fuel. (5) Reduction of mobile source air toxics, required by the Clean Air Act

Amendments of 1990, has been too long neglected by EPA. 

Achieving reductions in PM2.5 from mobile sources would also reduce regulatory pressure on 

stationary sources to find ever more costly ways to meet the National Ambient Air Quality 

Standard for concentrations of PM2.5 in the air. Electric utilities already face annual costs of 

$9.6 billion to reduce such hazardous air pollutants. (6) 

We also recommend that EPA take this opportunity to lead a nationwide transition to cleaner fuel 

in order to meet the requirements of the Clean Air Act Amendments of 1990 and ensure “the 

greatest degree of [air toxic] emissions reduction achievable” from motor vehicle exhaust. (15) 

Shifting to a mid-level ethanol blend is achievable with currently available technology and a 

sensible plan of action; however, the regulatory regime currently governing certification fuel and 

fuel marketability has thus far prevented automobile manufacturers and fuel refiners from 

initiating such a change. As EPA recognized in the Proposed Rule, meaningful emissions 

reductions can only come about “as part of a systems approach in addressing the impacts of 

motor vehicles and fuels on air quality and public health.” (16) EPA has both the power and legal 

authority to craft such an approach. With time—and the removal of regulatory disincentives for 

alternative fuels—the nation’s motor vehicles could all be running on cleaner, safer fuel and 

benefiting from the performance enhancement that a higher-octane blend would make possible. 

Accordingly, we respectfully request that EPA take the following steps to facilitate a nationwide 

transition to a cleaner, safer mid-level ethanol blend vehicle fuel:

- Approve a splash-blended, mid-level ethanol blend as a certification fuel;
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- Adjust the greenhouse gas emissions calculation for all vehicles certifying on this fuel to 

account for ethanol’s life-cycle carbon advantage over gasoline; 

- Extend to this fuel the one-pound waiver for Reid vapor pressure (RVP) that currently applies 

to E10; 

- Beginning with a future model year, require all new gasoline vehicles to be certified on this 

fuel; and 

- Consistent with the pace of adoption of both fuel and vehicles, limit the aromatic content of all 

light-duty motor vehicle fuel to the greatest degree achievable.

EPA Must Reduce Mobile Source Air Toxics in Motor Vehicle Fuel: What goes into motor 

vehicle fuel directly affects the emissions that come out the tailpipe. By transitioning to a midlevel ethanol blend, EPA would fulfill its statutory duty to regulate air toxics from mobile 

sources. In the 1990 Clean Air Act Amendments, Congress gave EPA the duty to “promulgate 

(and from time to time revise)” regulations governing emissions of “hazardous air pollutants 

from motor vehicles and motor vehicle fuels.” (25) Furthermore, Congress required that these 

regulations “reflect the greatest degree of emission reduction achievable through the application 

of technology which will be available” (26); in other words, the mandate is strict and technologyforcing. “Hazardous air pollutants,” as that term is used in section 202(l) of the Act, are 

synonymous with “mobile source air toxics” (MSATs) and include the aromatic compounds 

which currently make up approximately 20%-30% of light-duty motor vehicle fuel in the United 

States. On combustion, these aromatic hydrocarbons—which are air toxics in their own right—

produce benzene, toluene, ethylbenzene, xylene, 1,3-butadiene, polycyclic aromatic 

hydrocarbons (PAHs), and a host of other hazardous air pollutants. (27) In addition, the 

combustion of aromatics in motor vehicle engines produces dangerous levels of fine and ultrafine particulate matter (PM2.5 and UFPs), causing a range of environmental and human health 

effects, including thousands of deaths every year. (28) Finally, the combustion of aromatics in 

motor vehicle engines produces emissions of black carbon, one of the most powerful agents of 

climate change. Perhaps counterintuitively, in gasoline direct injection (GDI) engines (which are 

likely to become standard equipment in response to stricter fuel economy and greenhouse gas 

standards in the recent CAFE rule), emissions of black carbon and ultra-fine particles (UFPs) 

will increase if the level of aromatics in gasoline is not reduced. (29) 

EPA Has Not Met its Obligation to Regulate MSATs: EPA has acknowledged that the 

“hazardous air pollutants” that must be regulated under section 202(l) of the Clean Air Act 

include aromatics, yet, apart from requiring a small decrease in benzene content in 2007, (30) the 

Agency has not yet substantially reduced aromatics in motor vehicle fuel. In a study required by 

section 202(l)(1), EPA discussed aromatics, including “benzene, formaldehyde, and 1,3-

butadiene,” as well as the “gasoline particulate” that they produce. (31) In its 2001 MSAT Rule,

the Agency included in its list of MSATs the aromatics benzene, toluene, xylene, 1,3-butadiene, 

naphthalene, and polycyclic organic matter (POM), a subclass of air toxics that includes all 

PAHs. (32) Nevertheless, EPA did not require any reductions in emissions beyond those already 

required by other existing or proposed mobile source regulations. (33) In its 2007 MSAT rule, 

EPA required a slight reduction in benzene content in vehicle fuel, but—based on several factual 

predicates that have since changed, (34) the Agency declined to regulate aromatics further. (35)
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Today, EPA has an opportunity to correct this deficiency and reduce the dangers of motor 

vehicle exhaust to public health. As noted in the Proposed Rule, more than 158 million 

Americans are currently experiencing unhealthy levels of air pollution, which are linked with 

respiratory and cardiovascular problems and other adverse health impacts that lead to increased 

medication use, hospital admissions, emergency department visits, and premature mortality. 

Motor vehicles are a particularly important source of exposure to air pollution, especially in 

urban areas. (36) 

Because current motor vehicle fuel is a major contributor to air toxics and particulate matter in 

the atmosphere, (37) and because benzene, toluene, ethylbenzene, and xylene (BTEX) (the class 

of aromatics added in the highest quantities to motor vehicle fuel) all produce benzene on 

combustion, EPA has the authority, and indeed the obligation, to reduce the aromatic content of 

motor vehicle fuel under sections 202(l) and 211 of the Clean Air Act. EPA must promulgate 

regulations that “reflect the greatest degree of emissions reduction achievable through the 

application of technology which will be available, taking into consideration the availability and 

costs of the technology, and noise, energy, and safety factors, and lead time.” (38) While 

declining to regulate aromatics in 2007 because of cost and other factual predicates that are no 

longer applicable, the Agency acknowledged that “[t]here may be compelling reasons to consider 

aromatics control in the future, especially regarding reduction in secondary PM2.5 emissions, to 

the extent that evidence supports a role for aromatics in secondary PM2.5 formation.” (39) The 

Agency now acknowledges the important role of aromatics in PM2.5 formation, (40) and the 

time for cleaner gasoline has come; indeed, it is long overdue. EPA leadership to initiate a 

nationwide switch to a cleaner, less aromatics-intensive, mid-level ethanol blend would 

constitute a great stride toward a cleaner energy future and produce widespread environmental 

and health benefits.

MSATs Have a Significant Impact on Human and Environmental Health, Especially in Urban 

Areas: Regulation of gasoline aromatics under Clean Air Act sections 211 and 202(l) is urgently 

needed because aromatics cause thousands of deaths each year, along with a host of other serious 

health and environmental problems. All of these problems would be greatly ameliorated through 

the use of a cleaner, mid-level ethanol blend. 

Benzene, toluene, ethylbenzene, and xylene, known collectively as “BTEX,” are all aromatic 

compounds included in gasoline to increase its octane rating. These air toxics, which belong to a 

class known as volatile organic compounds (VOCs), are emitted in tailpipe exhaust. Recent 

studies show that the majority of BTEX (83%-100%) on and near roadways is the result of 

gasoline tailpipe emissions. (41) As a result, BTEX from gasoline exhaust has significant health 

and developmental implications, especially for urban populations (42)—pertinent to EPA’s 

environmental justice criterion in the Proposed Rule. (43) 

On their own, VOCs cause many harmful effects on the human nervous system and can 

contaminate soil and groundwater with lasting effects. (44) Benzene, for example, is a known 

human carcinogen and causes a range of health effects, including blood disorders and 

immunotoxicity. (45) Furthermore, once in the ambient air, VOCs combine through complex 

chemical pathways to produce significant amounts of fine particle pollution, including 

particularly dangerous ultra-fine particles (UFPs), which can become coated by toxic polycyclic 
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aromatic compounds (PAHs), allowing these harmful cytotoxic and mutagenic chemicals to 

penetrate deep inside the human body. Each of these dangerous forms of pollution caused by 

aromatics is discussed below. 

Fine Particle Pollution (PM2.5): Aromatics in gasoline are among the most efficient 

anthropogenic precursors of secondary organic aerosol (SOA), (46) a species of fine particulate 

matter (PM2.5)—i.e., particles less than 2.5 micrometers in diameter. It is widely acknowledged 

that EPA’s current models do not adequately capture the SOA-forming potential of gasoline 

aromatics, (47) nor do motor vehicle emissions tests capture the formation of SOA. (48) 

However, aromatics’ SOA formation potential is of deadly import, because SOA is a major 

contributor to the PM2.5 burden throughout the United States, particularly in urban areas. (49) In 

addition to SOA, gasoline aromatics produce direct PM in the form of black carbon and PAHs, 

both discussed below. (50) In fact, the entire PM2.5 formation potential of gasoline comes from 

aromatics. (51) Ethanol, by contrast, does not produce PM2.5, as EPA’s own investigations have 

concluded. (52) Thus, a reduction in the aromatic content of motor vehicle fuel would 

significantly reduce PM2.5 levels in urban areas and near roadways. (53) 

Because PM2.5 is particularly lethal, power plants and other stationary sources are strictly 

regulated to reduce emissions, and States must meet a National Ambient Air Quality Standard 

(NAAQS) that limits concentrations of PM2.5 in the air. 

Nevertheless, States are currently unable to obtain routine State Implementation Plan credit 

toward meeting the NAAQS by reducing SOA from motor vehicles, (57) and EPA’s own PM2.5 

regulations focus mainly on stationary sources such as power plants. As a result, costly 

reductions are required in remote areas, while relatively little is done to reduce PM2.5—

particularly SOA—from motor vehicles, even in densely populated areas, where the benefits of 

reducing mobile source PM would be significantly higher on a per-ton basis. (58) This anomaly 

is particularly perverse considering that, unlike stationary source reductions, which cost billions 

of dollars per year to implement, (59) reducing SOA from motor vehicle fuel could save 

consumers billions of dollars per year at the pump. (60) Focusing exclusively on stationary 

sources thus places an unnecessary burden on state regulators, who must require unnecessarily 

costly ways to reduce PM pollution in order to meet their NAAQS obligations. This regulatory 

disparity between mobile and stationary sources effectively grants refiners a “hidden subsidy,” 

since aromatics’ considerable health costs are both borne directly by affected citizens, taxpayers, 

and health providers and transferred indirectly to other businesses by state environmental 

authorities—even though aromatics could be significantly reduced by ethanol at far lower cost 

than other means of control. 

When it comes to fine particulate pollution, size and type matter. Because of their small size, 

ultra-fine particles (UFPs)—that is, particles less than 100 nanometers in diameter—are an 

especially dangerous byproduct of high-distillate aromatics, (61) including naphthalene, in 

gasoline. Unlike larger particles, which can sometimes deposit in the mouth and throat after 

inhalation, UFPs are likely to travel deep into the alveolar region of the lungs, (62) which allows 

them to function as vehicles on which dangerous toxic compounds such as PAHs (63) (also 

present in large quantities in gasoline exhaust as a result of aromatics combustion) can enter 

bodily tissues and wreak havoc on a cellular level. (64) Once in the alveolar tissue, UFP-borne 
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PAHs (and the particulate matter itself) can be absorbed into the bloodstream and enter other 

bodily organs, such as the liver. (65) UFPs in gasoline exhaust exhibit a relatively high number 

of these so-called “redox-active” compounds. Paired with greater bioavailability and lung 

retention than other forms of particulate, this makes UFPs highly pathogenic. (66) Studies have 

linked UFPs to myriad adverse health effects, including asthma and other respiratory conditions; 

cardiovascular disease; preterm births; a wide range of cancers; DNA damage; even autism and 

brain disorders. (67) Furthermore, the small size of UFPs means that—beyond the added danger 

posed by particle type—each ton of UFPs is more dangerous than a ton of PM2.5 because UFP 

pollution contains many more particles per unit mass (this property is known as “particle 

number,” or “PN”). (68) However, because EPA currently regulates only mass, but not particle 

number or type, of particulate pollution, (69) the Agency has yet to separately measure or 

regulate these highly pathogenic UFPs. Of particular concern, emission reduction technology in 

newer vehicles tends to produce more high-particle-number emissions, even as it reduces 

particulate emissions by mass. (70) Thus, the health impact of UFP pollution will only grow as 

the next generation of direct injection vehicles replaces older port injection vehicles. Perhaps 

counterintuitively, newer vehicles tend to emit more UFPs than legacy vehicles by as much as 

fourfold. (71) 

PAHs are a chemical subset of polycyclic organic matter (POM) and are a particularly 

dangerous, yet largely unregulated, air toxic largely attributable to mobile sources generally, (72) 

and gasoline-fueled vehicles in particular. (73) As with UFPs, PAHs are produced by aromatics 

in gasoline, (74) particularly high-distillate aromatics. (75) PAHs can exist in both gaseous and 

particle form. They are oxidative derivatives of gasoline aromatics and result from incomplete 

combustion of fused aromatic rings. Many aromatics are themselves PAHs. Naphthalene, for 

instance, is a dangerous aromatic in motor vehicle fuel—and it is the simplest of the PAHs. 

However, the most harmful PAHs are the high-molecular-weight PAHs that coat UFPs. (76) 

Urban UFPs disproportionately carry PAHs. (77) As EPA noted in its 2007 MSAT rule, “[r]ecent 

studies have found that maternal exposures to PAHs in a population of pregnant women were 

associated with several adverse birth outcomes, including low birth weight and reduced length at 

birth, as well as impaired cognitive development at age three.” (78) Laboratory experiments 

show that fetal nervous systems may be particularly sensitive to PAHs, (79) which can cross the 

placenta and blood-brain barrier from mother to child. (80) PAHs have been linked to a range of 

adverse health outcomes in infants and children, including developmental delay, reduced IQ, 

anxiety/depression, and possible endocrine disruption. (81) Motor vehicle emissions are a major 

source of PAHs found to contaminate groundwater and aquatic organisms. (82) As with other 

hazardous air toxics from gasoline, the worst effects of PAHs are found in urban areas. (83) 

Although PAHs and their associated health risks are better understood today than in the recent 

past, EPA restates verbatim its six-year-old statement of uncertainty about their prevalence. (84)

The temperature at which a given percentage of fuel, by volume, will evaporate is an important 

characteristic from a pollution perspective. Gasoline contains a wide range of components, 

including aromatics of various molecular weights and chemical properties, which boil at 

different temperatures. High-distillate aromatics evaporate only at very high temperatures and 

often do not vaporize during gasoline combustion. (85) “T50,” “T90,” and “endpoint” numbers 

for a given fuel refer to the temperatures at which 50%, 90%, and 100% of the fuel will 

evaporate, respectively. Since compounds that do not evaporate during engine combustion are 
Tier 3 Summary and Analysis of Comments

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often emitted from the tailpipe in the form of dangerous pollution, the more high boilers present 

in a fuel blend (and thus the higher the T50, T90, and endpoint numbers of the fuel), the more 

pollution the fuel will cause. If T50, T90, and endpoint numbers are reduced, on the other hand, 

pollution will decrease.

High-distillate aromatics raise the T50, T90, and endpoint numbers of a fuel blend because they 

evaporate only at very high temperatures. As discussed above, these “heavy” aromatics, 

including naphthalene, are the primary source for dangerous UFPs and the PAHs that bind to 

them. (86) It is no surprise, then, that fuel blends with higher levels of high-distillate aromatics 

produce more of nearly every type of pollution. In a 2010 SAE paper, Honda reports that 

predictive modeling indicated that aromatics with a high boiling point and a high double bond 

equivalent (DBE) value tended to produce more PM emissions. . . . [A]ll of the additional PM is 

considered a PAH . . . with a high boiling point or soot. The higher the boiling point hydrocarbon 

added, the more the PM increases. This trend is particularly notable with aromatic substances. 

(87)

EPA’s EPAct model corroborates this observation. To produce the fuels used in the EPAct study, 

modelers created new types of gasoline “blendstock” to mix with ethanol, so that the final blends 

would maintain the same T50 and T90 numbers as the non-ethanol fuels used in the study. 

Because ethanol has a relatively low boiling point, mixing ethanol with standard gasoline (i.e., 

“splash blending”) results in final blends with significantly lower T50 and T90 numbers. 

Therefore, in order to maintain the original T50 and T90 numbers, modelers had to increase the 

high boiler components of the gasoline blendstock when adding ethanol—resulting in blends 

with a much larger proportion of high-distillate aromatics than would be permitted in market 

gasoline. (For a discussion of the significance of this methodology, see the comments at Part 

IV.A.). 

Adding high-distillate aromatics caused nearly every type of tailpipe pollution to increase. For 

example, the EPAct study found hot-running NOx emissions to be “dominated by the effect of . . 

. ethanol, followed closely by aromatics.” (88) This result can only be explained by the addition 

of high-distillate aromatics to compensate for ethanol’s favorable effect on the T50 and T90 

numbers of blended fuel. (89) Not surprisingly, these harmful aromatics increased NOx 

emissions. That effect cannot be attributed to ethanol. When ethanol is simply splash-blended 

into ordinary gasoline, it has the opposite effect—it lowers NOx emissions. (90) 

In addition to producing traditional air pollutants, aromatics in motor vehicle fuel contribute to 

global climate change.

Black carbon (BC), commonly referred to as “soot,” is the “carbonaceous component of PM that 

absorbs all wavelengths of solar radiation.” (91) The term “BC” is often used interchangeably 

with elemental carbon (EC), but the two terms refer to different measurement techniques that 

capture roughly the same substance. (92) BC emissions result from incomplete engine

combustion, which is worsened by the presence of high-distillate aromatics in motor vehicle fuel. 

(93) BC is considered either PM2.5 or UFP, depending on its size. Apart from being a form of 

direct PM with various health and environmental effects described above, BC has an established 

impact on climate change. (94) 
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After CO2, BC is considered the second largest contributor to global warming, and it causes net 

radiative forcing through a number of processes. (95) For instance, its “high capacity for light 

absorption and its role in key atmospheric processes link it to a range of climate impacts, 

including increased temperatures, accelerated ice and snow melt, and disruptions in precipitation 

patterns.” (96) When deposited on snow and ice, BC darkens the surface, thereby decreasing 

reflectivity and increasing absorption; this raises surface temperatures and accelerates melting. 

(97) BC deposits have been linked to accelerated snow and ice melting in certain areas, (98) 

including Himalayan glaciers (99) and in the Western United States, where BC deposition on 

mountain glaciers causes early spring melting and impacts freshwater resources. (100) EPA, in 

the Regulatory Impact Assessment accompanying last year’s proposed PM implementation rule, 

cites research showing that “[p]er unit of mass in the atmosphere, BC can absorb a million times 

more energy than CO2.” (101) Because BC is such a powerful agent of climate change, and yet 

is relatively short-lived, controlling its emission from fossil fuel has been identified as one of the 

most effective and immediate ways of slowing global climate change. (102) 

Mobile sources are “the dominant contributor to total BC emissions in the United States.” (103) 

Indeed, EPA estimates that mobile sources are responsible for a majority—52.3%— of BC 

emissions in the USA. (104) Although heavy-duty diesel vehicles have been thought to be the 

main contributor of BC emissions, recent studies show that light-duty gasoline emissions form a 

very significant part of the overall BC burden and that past research seriously underestimated 

this contribution. (105) In fact, recent tests performed by the California Air Resources Board 

(CARB) estimate that—in stark contrast to prior understanding—EC accounts for approximately 

70% of PM mass emissions from gasoline-powered light duty vehicles. (106) What is worse, 

newer, gasoline direct injection (GDI) engines emit significantly more black carbon than legacy 

port fuel injection (PFI) engines, (107) so the contribution of gasoline vehicles to ambient soot is 

likely to significantly worsen in future years as auto manufacturers gravitate to GDI technology 

in order to meet more stringent fuel economy and CO2 emissions standards in years 2017 and 

beyond. 

In sum, soot formed by aromatics in motor vehicle fuel has a significant impact on climate 

change, putting it at direct odds with EPA’s goal in the recent 2017 and Later Model Year Light 

Duty Vehicle Greenhouse Gas Emissions and Corporate Average Fuel Economy Standards (108) 

and with the Administration’s strong commitment to slowing and preventing global climate 

change. As noted above, black carbon, like all gasoline PM, is attributable solely to the aromatic 

content of the fuel. (109) 

Beyond black carbon, current motor vehicle fuel negatively impacts climate change in several 

additional ways. SOA, produced in significant quantities by gasoline aromatics, has a direct 

climate forcing effect. (110) In addition, current motor vehicle fuel blends, and aromatics in 

particular, produce significant greenhouse gas pollution that would be mitigated in mid-level 

ethanol blends. (111) 

Splash blending ethanol with gasoline blendstock, at a level between 20% and 45% on a 

volumetric basis, would produce a high-octane, clean fuel with significantly less aromatic 

content, thereby reducing numerous forms of tailpipe pollution, including BTEX, (112) UFPs, 

(113) PAHs, (114) SOA, (115) and black carbon, (116) in accordance with EPA’s statutory 
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MSAT obligation. (117) In addition, because of ethanol’s oxygenate quality, a mid-level ethanol 

blend would reduce pollution, particularly carbon monoxide (CO), beyond what could be 

achieved by simple reduction of toxic aromatics. (118) Other significant co-benefits would 

include increased U.S. energy security, decreased retail fuel prices, and—as discussed below—

reduced CO2 emissions on a life-cycle basis. 

Ethanol is a motor vehicle fuel derived from renewable biomass, which removes carbon dioxide 

from the air as it grows. As a result, tailpipe CO2 emissions from ethanol are offset by upstream 

reductions. The majority of ethanol in the U.S. market is so-called “conventional biofuel,” 

derived from corn starch. (119) However, the Renewable Fuel Standard (RFS) requires 

significant increases in the use of advanced and cellulosic biofuels in coming years. (120) 

“Advanced biofuel,” often made from sugar cane, must be at least 50% less carbon-intensive 

than gasoline, while ethanol qualifying as “cellulosic” must be at least 60% less carbonintensive. 

According to EPA’s indirect land use analyses, corn-based ethanol is responsible for 21% less 

greenhouse gas pollution than gasoline on a life-cycle basis. (121) However, recent studies show 

that EPA models may significantly underestimate the carbon sequestration effects of corn, and 

one study estimates that corn ethanol is actually 48% to 59% less carbon-intensive than gasoline. 

(122) Similarly, a 2007 study by Argonne National Laboratory found life-cycle greenhouse gas 

reductions of 19% to 52% from the use of corn ethanol over gasoline, depending on the source of 

energy used during ethanol production. (123) This result is almost certainly conservative, as a 

nine-year USDA study of no-till corn (124) subsequently found that over half the increase in soil 

organic carbon (SOC) (used in the Argonne study to measure the carbon-sequestration effect of 

corn) occurs more than 30 cm below the surface, and that the model used in the Argonne study—

which relied on samples near the soil surface—significantly underestimated corn’s carbonsequestration benefits. (125) 

Corn is part of a small subset of plants known as C4 plants, meaning that the first product of 

carbon fixation in corn is a molecule with four carbon atoms, in contrast to most other plants, 

which produce a molecule having three carbon atoms (C3). The C4 pathway was discovered in 

the 1960s, (126) and it represents a major evolutionary efficiency gain over the more common 

C3 photosynthesis pathway. (127) Because C4 plants such as corn more efficiently absorb CO2 

in photosynthesis, they sequester more greenhouse gases proportionally than the more common 

C3 plants: In fact, although only 3% of plants use C4 photosynthesis, these plants are responsible 

for roughly 20% to 30% of total soil-based carbon fixation. (128) Corn’s carbon sequestration 

characteristics give ethanol a significant environmental advantage over fossil fuels, whose 

extraction and refinement result in significant carbon dioxide emissions, in addition to that 

produced when gasoline is burned as fuel.

Ethanol’s carbon sequestration advantage over gasoline will only grow as higher levels of nextgeneration and cellulosic biofuels enter the market, in response to RFS requirements, while the 

increasing share of tar sands, oil shale, and fracking technologies will result in substantially 

larger carbon footprints for the same amount of gasoline. 
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Finally, EPA should use its authority under sections 202 (l) and 211 to require a phase-down in 

the aromatic content of all gasoline blends, thereby ensuring that a cleaner, mid-level ethanol 

blend becomes widely available in the marketplace. As described above, (164) EPA is not 

currently meeting its statutory obligation to reduce air toxics in motor vehicle exhaust to the 

greatest extent achievable. However, no practical barrier remains, and a high-octane mid-level 

ethanol blend offers a ready alternative. Meanwhile, the extensive body of credible science 

detailing the serious environmental and health effects of aromatics in motor vehicle fuel makes 

the problem one of deadly import. EPA should require all new gasoline vehicles to certify on this 

new, cleaner fuel blend and then use its statutory authority to reduce the allowable aromatics 

content in gasoline blends—thus cutting both air toxics-related pollution and greenhouse gas 

pollution.

2 - Proposed Tier 3 Rule, 78 Fed. Reg. at 29909.

3 - Katherine von Stackelberg, et al., Public Health Impacts of Secondary Particulate Formation from 

Aromatic Hydrocarbons in Gasoline, Environmental Health 2013 12:19, Feb. 20, 2013, 

http://www.ehjournal.net/content/pdf/1476-069X-12-19.pdf.

4 - Proposed Tier 3 Rule, 78 Fed. Reg. at 29827.

5 - See infra Part III.B.3 & note 71.

6 - National Emission Standards for Hazardous Air Pollutants from Coal- and Oil-Fired Electric Utility 

Steam Generating Units and Standards of Performance for Fossil-Fuel-Fired Electric Utility, IndustrialCommercial-Institutional, and Small Industrial-Commercial-Institutional Steam Generating Units, 77 Fed. 

Reg. 9306 (Feb. 16, 2012), http://www.gpo.gov/fdsys/pkg/FR-2012-02-16/pdf/2012-806.pdf.

15 - 42 U.S.C. § 7521(l)(2).

16 - Proposed Tier 3 Rule, 78 Fed. Reg. at 29995.

25 - Clean Air Act § 202(l), 42 U.S.C. § 7521(l). 

26 - Id. 

27 - Elsewhere, the Clean Air Act provides that regulation of emissions of “toxic air pollutants” includes 

regulation of the “aromatic hydrocarbon content” of that fuel. 42 U.S.C. § 7545(k)(1)(A), (3)(A)(ii) 

(pertaining to reformulated gasoline); see also 42 U.S.C. § 7547(k)(10)(c) (defining “toxic air pollutants” 

to include benzene, 1,3 butadiene, and polycyclic organic matter (POM) [a term which includes PAHs 

such as naphthalene]). Another section of the Act explicitly includes the aromatics benzene “including 

benzene from gasoline,” toluene, and xylenes-in a list of “hazardous air pollutants” subject to regulation. 

Clean Air Act § 112, 49 U.S.C. § 7412 (pertaining to emissions from stationary sources). 

28 - See von Stackelberg, et al., supra note 3, at 1 (estimating a “baseline” of up to 4,700 deaths per year 

due to secondary organic aerosol (SOA) from gasoline, or over 6,300 deaths per year assuming 100% of 

aromatic-produced SOA in urban areas is from motor vehicles. These estimates did not take into account 

deaths from direct PM, the enhanced pathogenic qualities of UFPs, or PAH-related deaths); see infra Part 

III.B.6.a, III.B.3, III.B.4. 

29 - See infra notes 71, 107. 

30 - Control of Hazardous Air Pollutants from Mobile Sources, 72 Fed. Reg. 8428, 8477 (Feb. 26, 2007) 

[hereinafter “2007 MSAT Rule”]. 

31 - Control of Emissions of Hazardous Air Pollutants from Mobile Sources, 66 Fed. Reg. 17230, 17234 

(Mar. 29, 2001) [hereinafter “2001 MSAT Rule”]. 

32 - Id. at 17235. 

33 - Id. 

34 - See Appendix II. 

35 - 2007 MSAT Rule, 72 Fed. Reg. at 8478-79; see Appendix II for a complete discussion of the 

changes in factual predicate since 2007. 

36 - Proposed Tier 3 Rule, 78 Fed. Reg. at 29819. 
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37 - See California Office of Health Hazard Assessment, Summary of Scientific Meeting Held June, 2000 

on Approaches to Assessing Health Impacts of Gasoline-Related Exposures in California, 5 [hereinafter 

“2000 Assessment of Gasoline-Related Health Impacts”], available at 

http://www.oehha.ca.gov/public_info/pdf/GasOEHHA.pdf. 

38 - 42 U.S.C. § 7521(l)(2). 

39 - 2007 MSAT Rule, 72 Fed. Reg. at 8479. 

40 - Clean Air Fine Particle Implementation Rule, 72 Fed. Reg. 20,586, 20,593 (Apr. 25, 2007) 

[hereinafter “PM Implementation Rule”]. 

41 - See, e.g., Eric M. Fujita, et al., Concentrations of Air Toxics in Motor Vehicle-Dominated 

Environments, Health Effects Institute Research. Rep. No. 156, at 2 (2011); see also 2000 Assessment of 

Gasoline-Related Health Impacts, supra note 37, at 5 (“[I]t appears that light-duty gasoline vehicle 

particulate matter emissions are significantly underestimated in current inventories. Light-duty gasoline 

vehicles are the major source of 1,3-butadiene and BTEX.”). 

42 - K.P. Wyche, et al., Gas Phase Precursors to Anthropogenic Secondary Organic Aerosol: Detailed 

Observations of 1,3,5-Trimethylbenzene Photooxidation, 9 Atmos. Chem. Phys. 635 (2009) (“[Aromatic 

VOCs] make up as much as 40% of the total mass of anthropogenic hydrocarbon emissions in the city 

environment.”), available at http://www.atmos-chem-phys.net/9/635/2009/acp-9-635-2009.pdf; see also 

Frederica P. Perera, Prenatal Polycyclic Aromatic Hydrocarbon (PAH) Exposure and Child Behavior at 

Age 6-7 Years, 120 Environ. Health Perspectives 921, 921 (2012) (“Urban, minority populations in the 

United States often have disproportionate exposure to air pollution and are at greater risk for adverse 

health and developmental outcomes.”). 

43 - Proposed Tier 3 Rule, 78 Fed. Reg. at 29849. 

44 - See John S. Zogorski, et al., The Quality of Our Nation’s Waters: Volatile Organic Compounds in 

the Nation’s Ground Water and Drinking-Water Supply Wells, U.S. Department of the Interior, U.S. 

Geological Survey, Circular 1292, at 8, 9 (2006), available at 

http://pubs.usgs.gov/circ/circ1292/pdf/circular1292.pdf. 

45 - 2007 MSAT Rule, 72 Fed. Reg. at 8435 (citing EPA, Integrated Risk Information System 

File:Benzene (2000), http://www.epa.gov/iris/subst/0276.htm); see generally EPA National Center for 

Environmental Assessment, Rep. No. EPA/635/R-02/001F, Toxicological Review of Benzene 

(Noncancer Effects) (2002), available at http://www.epa.gov/iris/toxreviews/0276tr.pdf. 

46 - E.Z. Nordin, et al., Secondary Organic Aerosol Formation from Gasoline Passenger Vehicle 

Emissions Investigated in a Smog Chamber, 12 Atmos. Chem. & Phys. Discussions 31,725, 31,749 

(2012) (“As shown in this study gasoline exhaust readily forms secondary organic aerosol with a 

signature aerosol mass spectrum with similarities to the oxidized organic aerosol that commonly 

dominates the OA mass spectra in and downwind urban areas. This substantiates recent claims that 

gasoline SOA is a dominating source to SOA in and downwind large metropolitan areas.”), available at 

http://www.atmos-chem-phys-discuss.net/12/31725/2012/acpd-12-31725-2012-print.pdf; L. Hildebrandt, 

et al., High Formation of Secondary Organic Aerosol from the Photo-oxidation of Toluene, 9 Atmos. 

Chem. Phys. 2973, 2973 (2009), available at http://www.atmos-chem-phys.net/9/2973/2009/acp-9-2973-

2009.pdf (“Toluene and other aromatics have long been viewed as the dominant anthropogenic secondary 

organic aerosol precursors.”); id. at 2984 (“The SOA yields from the photo-oxidation of toluene are 

higher than previously reported values.”); J.A. de Gouw, et al., Sources of Particulate Matter in the 

Northeastern United States in Summer: 1. Direct Emissions and Secondary Formation of Organic Matter 

in Urban Plumes, 113 J. Geophys. Research D08301, at 8 (2008) (“Particulate yields [of OM] . . . are . . . 

highest for aromatic compounds.” (citation omitted)); see also id. at 1 (“Approximately 37% of the 

secondary formation [of aerosol organic matter] can be accounted for by the removal of aromatic 

precursors.”). 

47 - One recent study found that EPA’s CMAQ v5.0 model underestimates gasoline’s PM2.5 contribution 

by a factor of 3.8. Stackelberg, et al., supra note 3, at 5; see also Kenneth S. Docherty, et al., 

Apportionment of Primary and Secondary Organic Aerosols in Southern California During the 2005 

Study of Organic Aerosols in Riverside (SOAR-1), 42 Environ. Sci. Tech. 7655, 7660 (2008) (“With 
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regard to SOA yields, it has been shown that model predictions based on simulation chamber yields 

dramatically underestimate SOA formation in the polluted atmosphere.” (citing R. Volkamer, et al., 

Secondary Organic Aerosol Formation from Anthropogenic Air Pollution: Rapid and Higher than 

Expected, 33 Geophys. Research Letters 17 (2006))); Draft Regulatory Impact Analysis: Tier 3 Motor 

Vehicle Emission and Fuel Standards, at 7-66 (March 2013) [hereinafter “Tier 3 DRIA”] (“Studies have 

indicated that ambient OC levels may be underestimated by current model parameterizations. While the 

treatment of new precursors has likely reduced the model/measurement bias, underestimates can 

persist.”); Q. Zhang, et al, Ubiquity and Dominance of Oxygenated Species in Organic Aerosols in 

Anthropogenically-Influenced Northern Hemisphere Midlatitudes, 34 Geophys. Research Letters L13801, 

at 1 (2007) (“[S]econdary organic aerosols (SOA), formed by chemical transformation and condensation 

of volatile and semivolatile species, are underestimated by an order of magnitude or more by current 

models when applied in and downwind of urban areas/polluted regions.”). 

48 - See generally Nordin, et al., supra note 46, at 31726 (“[T]here is a lack of laboratory studies to 

systematically investigate SOA formation in real-world exhaust.”). 

49 - See sources cited supra note 46; see also Nordin, et al., supra note 46, at 31726 (“Gasoline vehicles 

have elevated emissions of volatile organic compounds during cold starts and idling and have recently 

been pointed out as potentially the main source of anthropogenic secondary organic aerosol (SOA) in 

megacities.”); PM Implementation Rule, 72 Fed. Reg. at 20593 (“Aromatic compounds such as toluene, 

xylene, and trimethyl benzene are considered to be the most significant anthropogenic SOA precursors 

and have been estimated to be responsible for 50 to 70 percent of total SOA in some airsheds.”); Wyche, 

et al., supra note 42, at 635; see also Elizabeth A. Stone, et al., A Comparison of Summertime Secondary 

Organic Aerosol Source Contributions at Contrasting Urban Locations, 43 Environ. Sci. Technol. 3448, 

3454 (2009) (finding spatial differences in the primary and secondary sources of OC between cities and 

noting that they “demonstrate the need to treat geographically distinct source regions individually in the 

study of source contributions to SOA”). 

50 - See infra Parts III.B.6.a, III.B.4. 

51 - See J.R. Odum, et al., The Atmospheric Aerosol-Forming Potential of Whole Gasoline Vapor, 276 

Science 96, 96 (1997) (“[T]he atmospheric organic aerosol formation potential of whole gasoline vapor 

can be accounted for solely in terms of the aromatic fraction of the fuel.”), available at 

http://www.unc.edu/courses/2007fall/envr/416/001/OdumScience97.pdf. 

52 - See Tier 3 DRIA, supra note 47, at 7-64. 

53 - See, e.g., R. Bahreini, et al., Gasoline Emissions Dominate Over Diesel in Formation of Secondary 

Organic Aerosol Mass, 39 Geophys. Research Letters L06805, at 1 (2012) (“[S]ubstantial reductions of 

SOA mass on local to global scales will be achieved by reducing gasoline vehicle emissions.”); Michael J. 

Kleeman, et al., Source Apportionment of Secondary Organic Aerosol During a Severe Photochemical 

Smog Episode, 41 Atmos. Environ. 576 (2007) (finding that gasoline engines represented the greatest 

anthropogenic contributor of SOA in Los Angeles during a smog event); 2000 Assessment of GasolineRelated Health Impacts, supra note 37, at 18 (“For some of the high molecular weight PAH, gasoline 

appears to be the dominant source. Naphthalene levels are higher in gasoline than in diesel.”); id. at 26 

(“Data from the Northern Front Range Study showed that even moderately clean vehicles emitted a lot 

more or comparable or higher emission rates of both gas phase and particle phase PAHs-than diesel 

vehicles.”); Shang Liu, et al., Secondary Organic Aerosol Formation from Fossil Fuel Sources Contribute 

Majority of Summertime Organic Mass at Bakersfield, 117 J. Geophys. Research D00V26, at 1 (2012) 

(“In urban areas, the major source [of the organic fraction of atmospheric particles] is fossil fuel 

combustion from gasoline- and diesel-powered vehicles and other industrial activities (e.g., oil 

burning).”), available at http://onlinelibrary.wiley.com/doi/10.1029/2012JD018170/pdf. 

57 - In order to obtain SIP credit for mobile source reductions, States would have to undertake costly 

studies to, in effect, prove to EPA that credit is warranted, and even then credit would not be ensured. See 

PM Implementation Rule, 72 Fed. Reg. at 20594. 

58 - EPA, Environmental Benefits Mapping and Analysis Program (BenMAP): RSM-based Benefit Per 

Ton Estimates, (estimating the national average benefit in per ton reduction of PM at $630,000 for mobile 
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sources and only $520,000 for point sources such as EGUs), 

http://www.epa.gov/airquality/benmap/bpt.html; see also Neal Fann, et al., The Influence of Location, 

Source, and Emission Type in Estimates of the Human Health Benefits of Reducing a Ton of Air 

Pollution, 2 Air Qual. Atmos. Health 169, 170, 173-74 (2009) (finding that “the size of the population 

exposed to PM2.5 and the susceptibility of that population to adverse health outcomes” is an important 

factor in calculating the benefit of pollution reduction, and that “area source and mobile source [as 

opposed to ‘point source’/EGU] carbonaceous particle emissions, in particular, show the highest [benefit 

per ton]—suggesting that the emissions and population centers exposed are colocated”). 

59 - See, e.g., National Emission Standards for Hazardous Air Pollutants from Coal- and Oil-Fired 

Electric Utility Steam Generating Units and Standards of Performance for Fossil-Fuel-Fired Electric 

Utility, Industrial-Commercial-Institutional, and Small Industrial-Commercial-Institutional Steam 

Generating Units, 77 Fed. Reg. 9304, 9305-06 & table 2 n.b (Feb. 16, 2012) [hereinafter “Utility 

MACT”], (estimating annual social costs of $9.6 billion to implement, with over 90% of monetized 

benefits coming from reduction in premature fatalities due to PM), http://www.gpo.gov/fdsys/pkg/FR2012-02-16/pdf/2012-806.pdf. 

60 - A recent study at Louisiana State University found that “each additional billion gallons of ethanol 

reduces gasoline prices as much as $0.06 per gallon. Considering U.S. ethanol production in 2010, which 

was more than 13 billion gallons, ethanol production could result in having lower gasoline prices of up to 

$0.78 per gallon.” Hassan Marzoughi, The Impact of Ethanol Production on the U.S. Gasoline Market 16 

(presented Feb. 4-7, 2012), 

http://www.ethanol.org/pdf/contentmgmt/The_Impact_of_Ethanol_Production_on_the_US_Gasoline_Ma

rket.pdf. Likewise, a study at Iowa State University suggests “that increases in ethanol production over 

the last decade have reduced overall blended fuel prices.” Notice of Decision Regarding Requests for a 

Waiver of the Renewable Fuel Standard, 77 Fed. Reg. 70752, 70766 (Nov. 27, 2012) [hereinafter RFS 

Waiver Denial] (citing Xiaodong Du & Dermot J. Hayes, The Impact of Ethanol Production on U.S. and 

Regional Gasoline Markets: An Update to 2012 (May 2012), available at 

http://www.card.iastate.edu/publications/synopsis.aspx?id=1166)). 

61 - See infra Part III.B.5. 

62 - See, e.g., Morton Lippmann & Roy E. Albert, The Effect of Particle Size on the Regional Deposition 

of Inhaled Aerosols in the Human Respiratory Tract, 30 Am. Indus. Hyg. Ass’n J. 257 (1969), available at 

http://legacy.library.ucsf.edu/documentStore/b/p/e/bpe89c00/Sbpe89c00.pdf. 

63 - See infra Part III.B.4. 

64 - Gwami Shrestha, et al., Black Carbon’s Properties and Role in the Environment: A Comprehensive 

Review, 2 Sustainability 294, 307 (2010), available at http://www.mdpi.com/2071-1050/2/1/294/pdf ; 

2000 Assessment of Gasoline-Related Health Impacts, supra note 37, at 4 (Because of their small size, 

UFPs “can serve as an important vehicle for carrying other toxicants into the lung.”). 

65 - Shrestha, et al., supra note 64, at 307-08; 2000 Assessment of Gasoline-Related Health Impacts, 

supra note 37, at 4. 

66 - Jesus A. Araujo & Andre E. Nel, Particulate Matter and Atherosclerosis: Role of Particle Size, 

Composition and Oxidative Stress, 6 Particle & Fibre Toxicology (2009), available at 

http://www.particleandfibretoxicology.com/content/6/1/24/ref (also noting that “[i]t will be important to 

determine whether all these factors confer greater toxicity to UFP in human subjects since they may imply 

the need for adjusting the metrics of exposure to take account of particle number, surface area, and 

oxidant potential”). 

67 - Lee Hotz, The Hidden Toll of Traffic Jams, The Wall Street. Journal, Nov. 8, 2011, at D1, available 

at http://online.wsj.com/article/SB10001424052970203733504577024000381790904.html. 

68 - See Araujo & Nel, supra note 66 (“[P]articles 85-90% of the total PM2.5 particle number. Therefore, 

it is conceivable that larger particle numbers in UFP atmospheres, despite a smaller mass, could result in 

larger biological effects. In our study, development of larger atherosclerotic lesions in the UFP exposures 

correlated with increased particle numbers rather than with PM mass.” (footnote call omitted)); Zhi Ning 

& Constantinos Sioutas, Atmospheric Processes Influencing Aerosols Generated by Combustion and the 
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12-20

Inference of Their Impact on Public Exposure: A Review, 10 Aerosol & Air Quality 43, 54-55 (2010) 

(“The emission of these smaller particles in the atmosphere may pose a greater threat to public health, 

since they deposit deeper in the human respiratory systems and their chemical composition appears to be 

intrinsically more toxic than the non-labile PM. . . . Given the increased toxicity of these semi-volatile 

species [e.g., PAHs], efforts should be made to reduce their emissions from newer vehicles, including 

reductions in their gas-phase precursors formed during the combustion process.”), available at 

http://aaqr.org/VOL10_No1_February2010/6_AAQR-09-05-IR-0036_43-58.pdf. 

69 - See 40 C.F.R. § 86.096-8(a)(1) (setting emissions standards in grams per mile). 

70 - See Ning & Sioutas, supra note 68, at 54 (“Advanced vehicle emission control technologies are 

effective in reducing solid, non-labile PM emissions by means of filtration. However, recent 

investigations have shown substantial increases (by one order of magnitude and often more) of particle 

number emissions from retrofitted-vehicles due to the formation of nucleation mode particles from 

organic vapors in the exhaust.”); Walter Piock, et al., Strategies Toward Meeting Future Particulate 

Matter Emission Requirements in Homogeneous Gasoline Direct Injection Engines, SAE International 

(2011), available at http://delphi.com/pdf/techpapers/2011-01-1212.pdf. 

71 - See Health Effects Institute Special Committee on Emerging Technologies, The Future of Vehicle 

Fuels and Technologies: Anticipating Health Benefits and Challenges 3 (2011) (“Because of the less 

complete mixing of fuel vapor and air [in a direct-injection engine] . . . , the particulate emissions of the 

engine increase, including the number of ultrafine particles.”); Felix Leach, et al., The Effect of Fuel 

Volatility and Aromatic Content on Particulate Emissions from GDI Engines (presented at 16th 

Combustion Generated Nanoparticles, Zurich, 2012), available at 

http://www.lav.ethz.ch/nanoparticle_conf/Former/Posters_I-L.pdf; Constantinos Sioutas, et al., Final 

Technical Report: Physical and Chemical Characteristics of PM in the LAB (Source Receptor Study): 

Topic C: Studies of the Effects of Varying Spatial and Temporal Patterns of Ambient Particulate Matter 

(PM) and Co-pollutants and Resulting Health Effects with Emphasis on the Role of Atmospheric 

Chemistry (Mar. 30, 2005) (“Compared to previous studies at the Caldecott tunnel, less particle mass but 

more particle numbers (by factors of 2-4 fold) are emitted by vehicles than was the case 7 years ago. As 

the emissions of carbonaceous PM of newer engines decreases, the formation of nucleation mode 

particles is favored due to the reduction of the available surface for adsorption of the semi-volatile 

material. The resulting supersaturation of the mostly organic vapor increases the production of nanoparticles by nucleation.”), available at http://www.epa.gov/ncer/reports/r827352C014fr.pdf; see also infra 

note 107 & accompanying text (discussing increased black carbon emission from direct injection 

engines). 

72 - See Control of Hazardous Air Pollutants from Mobile Sources, Regulatory Impact Analysis, at 3-112 

(2007) [hereinafter “2007 MSAT RIA”] (“Major sources of PAHs include mobile sources.”); Ning & 

Sioutas, supra note 68, at 50 (“PAH concentrations were consistently higher when the nearby freeway 

was busy with traffic during morning rush hours.”). 

73 - 2000 Assessment of Gasoline-Related Health Impacts, supra note 37, at 5 (“Light-duty gasoline 

vehicles emit particulate matter containing higher fractions of particulate PAHs [than heavy-duty diesel 

vehicles]. Light-duty gasoline vehicles are significant sources of gas phase PAHs. Cold starts, high 

accelerations, and high emitters account for most of the [LDV] particulate matter emissions. . . . [I]t 

appears that [LDV] particulate matter emissions are significantly underestimated in current inventories. 

Light-duty gasoline vehicles are the major source of 1,3-butadiene and BTEX.”). 

74 - See generally id.; Memorandum from Robert Harley, Department of Civil and Environmental 

Engineering, U.C. Berkeley, to Steve Brisby, Stationary Source Division, California Air Resources Board 

(Apr. 26, 2007) (“[L]owering heavy aromatics in gasoline could help to reduce polycyclic aromatic 

hydrocarbons (PAH), another class of toxic compounds that are not included currently in the predictive 

model’s definition of toxic pollutant emissions.”). 

75 - See infra Part III.B.5. 

76 - See Yuling Jia, et al., Estimated Reduction in Cancer Risk due to PAH Exposures If Source Control 

Measures during the 2008 Beijing Olympics Were Sustained, 119 Environ. Health Perspect. 815, 820 
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(2011) (noting the importance of including high-molecular-weight PAHs in pollution studies despite their 

low environmental concentrations because of the disproportionately high cancer risk associated with 

them), available at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3114816/; see also supra Part III.B.3 

(discussing UFPs). 

77 - Araujo & Nel, supra note 66 (“Urban UFP contain a higher content per unit mass of polycyclic 

aromatic hydrocarbons (PAH).”). 

78 - 72 Fed. Reg. at 8439. 

79 - Perera, supra note 42, at 921 (citing L.A. Brown, et al., Down-Regulation of Early Ionotrophic 

Glutamate Receptor Subunit Developmental Expression as a Mechanism for Observed Plasticity Deficits 

Following Gestational Exposure to Benzo(a)pyrene, 28 Neurotoxicology 965 (2007); M.M. McCallister, 

et al., Prenatal Exposure to Benzo(a)pyrene Impairs Later-Life Cortical Neuronal Function, 29 

Neurotoxicology 946 (2008); D.D. Wormley, Environmental Contaminant-Mixture Effects on CNS 

Development, Plasticity, and Behavior, 197 Toxicol. Appl. Pharmacol. 49 (2004)). 

80 - Perera, supra note 42, at 921 (citing Brown, supra note 79). 

81 - Id. 

82 - See EPA, Technical Factsheet on Polycyclic Aromatic Hydrocarbons (PAHs) (“If released to soil 

[benzo(a)pyrene] will be expected to adsorb very strongly and will not be expected to leach to the 

groundwater. However, its presence in some groundwater samples indicates that it can be transported 

there by some mechanism.”), available at http://www.epa.gov/ogwdw/pdfs/factsheets/soc/tech/pahs.pdf; 

2007 MSAT Rule, 72 Fed. Reg. at 8444 (“[R]ecent studies have reported gasoline and diesel vehicles as 

major contributors in the atmospheric deposition of PAHs to [various watersheds].”). 

83 - Kanae Bekki, et al., Evaluation of Toxic Activities of Polycyclic Aromatic Hydrocarbon Derivatives 

Using In Vitro Bioassay, 55 J. Health Sci. 601, 606-07 (2009) (“PAH ketones and quinines originating 

from gasoline and diesel engine exhausts are present at comparatively high concentrations . . . in urban 

air.”), available at http://dspace.lib.kanazawa-u.ac.jp/dspace/bitstream/2297/19415/1/PH-PR-BEKKI-K601.pdf. 

84 - Tier 3 DRIA, supra note 47, at 6-25 (“Trends in PAH deposition levels are difficult to discern 

because of highly variable ambient air concentrations, lack of consistency in monitoring methods, and the 

significant influence of local sources on deposition levels.”); 2007 MSAT RIA, supra note 72, at 3-112 

(same). Despite EPA’s recognition of the dangers of PAHs, the Agency excludes PAHs from the 

performance evaluation of its CMAQ model. See Tier 3 DRIA, supra note 47, at 7-58. 

85 - See Tier 3 DRIA, supra note 47, at 3-11 (“[G]asoline containing a large fraction of heavier aromatics 

compounds with high [double bond equivalent] values result in greater vehicle PM emissions.”). 

86 - See supra Parts III.B.3 and III.B.4; see also generally 2000 Assessment of Gasoline-Related Health 

Impacts, supra note 37, at 5 (“Light-duty gasoline and heavy-duty diesel vehicles emit significant 

numbers of ultrafine particles.”). 

87 - Koichiro Aikawa, et al., Development of a Predictive Model for Gasoline Vehicle Particulate Matter 

Emissions, 3 SAE Int’l J. Fuels & Lubricants, 610, 610-11 (Oct. 25, 2010). 

88 - EPAct/V2/E-89: Assessing the Effect of Five Gasoline Properties on Exhaust Emissions from LightDuty Vehicles Certified to Tier 2 Standards: Final Report 221, Rep. No. EPA-420-R-13-002 (2013) 

[hereinafter “EPAct Results Report”], available at 

http://www.epa.gov/otaq/models/moves/documents/420r13002.pdf; but see id. at 221 (finding that 

aromatics—not ethanol—“is the single most important effect [on cold-start NOx emissions] by a wide 

margin”); id. (finding RVP to be the most important term for hot-start NOx emissions, but suggesting 

measurement error); EPAct/V2/E-89: Assessing the Effect of Five Gasoline Properties on Exhaust 

Emissions from Light-Duty Vehicles Certified to Tier 2 Standards: Final Report on Program Design and 

Data Collection 76, Rep. No. EPA-420¬R-13-004 (2013) [hereinafter “EPAct Design Report”], available 

at http://www.epa.gov/otaq/models/moves/documents/420r13004.pdf (noting as one “source of 

measurement error and variability” that “dilute gaseous emission measurements such as NOx may have 

sample concentrations similar in magnitude to background for some portions of the test”). 
Chapter 12: Comments Unrelated to the Tier 3 Rulemaking

12-22

89 - EPA has acknowledged that the increased NOx emissions it has predicted for some ethanol blends 

“depend[] on how other fuel properties change.” Partial Grant of Clean Air Act Waiver Application 

Submitted by Growth Energy To Increase the Allowable Ethanol Content of Gasoline to 15 Percent, 76 

Fed. Reg. 4662, 4672 (Jan. 26, 2011) [hereinafter “2011 E15 Waiver”]. 

90 - See M. Matti Maricq, et al., The Impact of Ethanol Fuel Blends on PM Emissions from a Light-Duty 

GDI Vehicle, 46 Aerosol Sci. & Tech. 580 (2011) (finding decreases in NOx emissions of “about 

20%”when the ethanol content of fuel is increased from 0% to 17% or higher). 

91 - California Ai

Commenter: Governors’ Biofuels Coalition

EPA must ensure that its fuel models are updated to reflect new science and the realistic 

emissions from the combustion of commercial gasoline (as opposed to unrealistic certification 

fuels). 

One of the top priorities should be for EPA to make sure that its Community Multiscale Air 

Quality (CMAQ) model recognizes the dominant role gasoline aromatics play in urban PM2.5 

secondary organic aerosol (SOA) emissions. A recent Harvard study has confirmed that EPA’s 

models under-predict SOA emissions by at least a factor of two to four times, and that they are 

responsible for tens of billions of dollars worth of avoidable public health impacts.3 

EPA’s final rule should recognize the air and water pollution health risks from highly toxic 

polycyclic aromatic hydrocarbons (PAHs), which EPA acknowledges in its regulatory impact 

analysis, but for some reason does not currently regulate for mobile sources. We are surprised 

and disappointed that EPA has failed to consider recent studies by automakers which show that 

E30+ blends are able to reduce these particle-borne PAH emissions by 45 to 60 percent or more, 

and we urge the EPA to include these findings in the final rule.4 

EPA should take this opportunity to correct the deficiencies in last year’s GHG-CAFE rule, and 

recognize ethanol’s carbon reduction benefits. Proper recognition of ethanol’s lower carbon 

footprint compared to gasoline — and especially gasoline aromatic compounds —would lead 

EPA to incentivize automakers’ post-2016 model years to manufacture E30 capable and 

optimized vehicles able to take full advantage of the high octane, high performance, ultra-low 

emissions of E30 blends. 

A final rule that fails to improve U.S. transportation fuel standards by reducing aromatic 

compounds is the wrong policy for America. On behalf of the Coalition, I respectfully urge you 

to modify the proposed rule so as to provide market-based incentives and encourage the costeffective substitution of domestic clean octane alternatives for toxic aromatic compounds derived 

largely from imported crude oil. 

3 Katherine von Stackelberg, et al., 12 Public Health Impacts ofSecondary Particulate Formation from 

Aromatic Hydrocarbons in Gasoline, Environmental Health (2013), available at 

http://www.ehjournal.net/content/12/1/19

4

See Koichiro Aikawa, et al., Development of a Predictive Model for Gasoline Vehicle Particulate 

Matter Emissions,SAE International (Oct. 25, 2010); M.A. Costagliola, et al., Combustion Efficiency and 

Engine Out Emissions of a S.I. Engine Fueled with Alcohol/Gasoline Blends, Applied Energy (2012); M. 
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Matti Maricq, et al., The Impact ofEthanol Fuel Blends on PM Emissions from a Light-Duty GDI Vehicle, 

46 Aerosol Sci. & Tech. 576 (2012).

Commenter: Growth Energy

While Aromatic Gasoline Components Substantially Increase PM Emissions, Ethanol Improves 

Air Quality: As we noted in previous comments to the Agency, numerous studies have looked at 

the impact of fuel quality on emissions from vehicles. These studies have found that the heavier 

gasoline components-aromatics - substantially increase particulate matter (PM) emissions 

(Iizuka, M., Kirii, A., Takeda, H., Watanabe, H. (2007). Effect of Fuel Properties on Particulate 

Matter Emissions from a Direct Injection Gasoline Vehicle. JSAE Technical Paper 20074414, 

2007, http://www.pecj.or.jp/japanese/overseas/asian/asia_symp_5th/pdf_5th/15-

MasashiIizuka.pdf; Jetter, J. (2010). Effect of Fuel Composition on PM Emissions, LEV III 

Workshop, May 18, 2010, El Monte, California; Aikawa, K., Sakurai, T., Jetter, J.J. (2010). 

Development of a Predictive Model for Gasoline Vehicle Particulate Matter Emissions. SAE 

Technical Paper 2010-01-2115. DOI: 10.4271/2010-01-2115; Khalek I.A., Bougher T., Jetter, J. 

(2010). Particle Emissions from a 2009 Gasoline Direct Injection Engine Using Different 

Commercially Available Fuels. SAE Technical Paper 2010-01-2117. DOI: 10.4271/2010-01-

2117.) 

Alternatively, there is substantial evidence that increased ethanol will actually reduce particulate 

matter mass and number emissions (PM and PN) from the vehicle fleet. Szybist et al.,(J. Szybist, 

A. Youngquist, T. Barone, J. Storey, W. Moore, M. Foster, and K. Confer, Ethanol Blends and 

Engine Operating Strategy Effects on Light-Duty Spark Ignition Engine Particle Emissions, 

Energy and Fuels, vol. 25, pp. 4977-4985, 2011) also summarize recent literature on how 

ethanol affects production engines:

A number of investigations have examined the effect of ethanol content on particle emissions in 

vehicles. Storey et al. found that blends of 10 and 20% ethanol in gasoline (E10 and E20) 

decreased particle number emissions during vehicle drive cycles, with the 20% blend decreasing 

particles by about 40% during the high-load US06 vehicle drive cycle. In comparison to 

gasoline, He et al. found a 20% reduction in particle emissions with E20 but no change with E10. 

Khalek and Bougher showed that E10 increased particle emissions compared to two different 

gasoline formulations, both with higher volatility than the E10. This works showed the 

importance of the hydrocarbon fraction of the E10 blend and suggests that the heavier 

hydrocarbons used to control vapor pressure of E10 may also increase particulate emissions. 

Aakko and Nylund found that the particle mass emissions from 85% ethanol (E85) were 

comparable to those with gasoline in a PFI vehicle but that DI (direct injection) fueling with 

gasoline produced particle emissions that were an order of magnitude higher. 

The Szybist et al. study investigated the effects of fuel type, fueling strategy, and engine 

breathing strategy on particle emissions in a flexible spark ignited engine that was designed for 

optimization with ethanol. They report:

When DI fueling is used for gasoline and E20, the particle number emissions are increased by 1 

to 2 orders of magnitude compared to PFI fueling, depending upon the fuel injection timing. In 
Chapter 12: Comments Unrelated to the Tier 3 Rulemaking

12-24

contrast, when DI fueling is used with E85, the particle number emissions remain low and 

comparable to PFI fueling. Thus, by using E85, the efficiency and power advantages of DI 

fueling can be gained without generating the increase in particle emissions observed with 

gasoline and E20. The main finding of the study is that use of E85 results in 1 to 2 orders of 

magnitude reduction in particle emissions relative to sDI (spray-guided DI) fueling with gasoline 

and E20. Furthermore, sDI particle emissions with E85 are similar to that for PFI fueling with 

gasoline. Thus, an increase in particle emissions beyond that of PFI engines can be prevented 

while gaining the efficiency of DI engines using E85. 

Storey et al., 2010 (J. Storey, T. Barone, K. Norman, and S. Lewis, Ethanol Blend Effects On 

Direct Injection Spark-Ignition Gasoline Vehicle Particulate Matter Emissions, SAE publication 

2010-01-2129) characterized the emissions, including PM and aldehydes, from a U.S. legal 

stoichiometric direct injected spark-ignited (DISI) vehicle operating on E0, E10, and E20. The 

PM emissions were characterized for mass, size, number concentration and OC-EC (organic 

carbon-elemental carbon) content. The DISI particle number-size distribution curves were 

similar in shape to light-duty diesel vehicles without Diesel Particle Filters, but had lower overall 

particle number and mass emissions. The aggressive US06 transient cycle had much higher PM 

mass emissions in comparison to the PM mass emission observed for the FTP. With respect to 

added ethanol, Storey et al. concluded:

Ethanol blends reduced the PM mass and number concentration emissions for both transient and 

steady-state cycles. By increasing the ethanol blend level from E0 to E20, the average mass 

emissions declined 30% and 42% over the FTP and US06, respectively. Measurements during 

hot cycle transient operation demonstrated that E20 also lowered particle number concentrations. 

The adoption of small displacement, turbocharged DISI engines into the U.S. fleet is likely to 

continue in the future, and the results of this study suggest that increasing ethanol blend levels in 

gasoline will lower DISI PM emissions. In addition, increasing ethanol content significantly 

reduced the number concentration of 50 and 100 nm particles during gradual and wide open 

throttle (WOT) accelerations. 

Maricq et al., 2012 (M. Maricq, J. Szente, and K. Jahr: The Impact of Ethanol Fuel Blends on 

PM Emissions from a Light Duty GDI Vehicle, Aerosol Science and Technology, 465, 576-583) 

tested a light-duty truck equipped with a 3.5-L V6 gasoline turbocharged direct injection engine 

that is representative of current GDI products, but contained prototype elements that allowed 

changes in engine calibrations. Because PM formation in GDI engines is sensitive to a number of 

operating parameters, two engine calibrations were examined to gauge the robustness of the 

results. The study used four fuels: certification test gasoline (E0), a commercial E10 fuel similar 

to that expected for future certification, a commercial pump grade E10, and a commercial E100 

fuel used for blending. E100 and E0 were splash-blended to produce E17, E32, and E45 fuels. 

Maricq et al. report:

As the ethanol level in gasoline increases from 0% to 20%, there is possibly a small (<20%) 

benefit in PM mass and particle number emissions, but this is within test variability. When the 

ethanol content increases to >30%, there is a statistically significant 20%-45% reduction in PM 

mass and number emissions observed for both engine calibrations. 
Tier 3 Summary and Analysis of Comments

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The results reported by Zhang (Zhang et al, “A Comparison of Total Mass, Particle size 

Distribution and Particle Number Emissions of Light Duty Vehicles tested at Haagen-Smit 

Laboratory from 2009 to 2010,” In Proceedings of 21st CRC Real World Emissions Workshop, 

San Diego, CA, USA, 20-23 March 2011) are also particularly informative. In this testing, a 

2008 FFV was tested on a hot Unified Cycle on E6, E35, E65, and E85. Ethanol appears to have 

caused a large reduction in PM emissions (and particularly PN) from E6 to E35, with further PM 

reductions as ethanol concentration increased. However, the most significant PM and PN 

reductions are between E6 and E35. 

EPA’s analysis of EPACT data shows the possibility of slightly higher PM emissions with 

increasing ethanol concentration. However, the EPACT test fleet was all Tier 2 vehicles, with 

few if any vehicles with direct injection. Direct injection vehicles can experience higher baseline 

PM emissions than ported fuel injected vehicles, which is the predominate fuel system 

technology utilized for Tier 2 vehicles. It is likely that increasing ethanol content would reduce 

PM on DI vehicles, as shown in the previously referenced studies in these comments. Also, the 

fuels used in the EPACT testing program were match-blended. The higher ethanol blend used in 

the EPACT study - an E20 fuel - is not likely to be representative of a higher ethanol blend that 

would have higher octane. Therefore, the EPACT testing results are not applicable with respect 

to PM emissions for the 2017 and later Tier 3 fleet. 

Thus, there are now a substantial number of studies showing that ethanol blends of 20 percent 

and higher reduce PM mass and number emissions in a variety of engines and vehicles. EPA 

should review these studies in detail and give serious consideration to further regulate the 

harmful components of gasoline as well as to encourage the use of additional ethanol as a means 

to improve the nation’s air quality. 

Commenter: INEOS Bio

Aromatics and Toxics: INEOS Bio urges the EPA to reconsider the potential health effect 

benefits associated with these higher ethanol blends. Ethanol is a high octane, low cost and nontoxic alternative fuel that can be used to displace the aromatics in gasoline. These are highly 

toxic chemicals that are the subject of multiple regulatory constraints under the CAA. EPA’s 

own discussion of air toxics makes clear that auto exhaust remains the primary source of air toxic 

exposure for individuals, especially those living near roadways. In fact it is estimated that 1 in 3 

people still live in areas that exceed at least one of the health-based National Ambient Air 

Quality Standards (NAAQS), and residing where ozone (also known as smog) levels exceed the 

federal standard.

EPA is required to set pollution standards for new light-duty vehicles under section 202 of the 

Clean Air Act. They are also required to set standards at a level that protects public health and 

welfare. The original CAA covered mobile source pollution standards for smog-forming, toxics, 

and other emissions for decades. Following the Supreme Court’s decision in Massachusetts v. 

EPA that ruled that greenhouse gas emissions are pollutants under the CAA and that those gases 

do endanger public health, the agency was required to set global warming pollution standards for 

vehicles under the CAA. Another provision of the 1990 CAA - the mobile source air toxics 

(MSAT) provision, requires EPA to reduce toxics as far as technology will permit. EPA has not 
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enforced this section except to reduce benzene by only small amounts in 2007, notwithstanding 

that the US is abundant in non-toxic alternatives such as ethanol. It seems that it would be 

appropriate to consider enforcing this section as increased volumes of ethanol become available. 

Biofuels and Their Supportive Policies Are Important to the U.S. Fuel Supply: The federal RFS, 

enacted in 2005 and updated in 2007, is an important tool in achieving the objectives of energy 

independence and pollution reduction. The RFS is the single most important federal policy 

driving investment and commercialization of conventional and advanced biofuels. Biofuel 

production under the RFS has already displaced nearly 10 percent of gasoline consumption and 

will account for more than 20 percent of U.S. transportation fuel by 2022. Biofuel production 

under the RFS reduced the need for imported oil by more than 462 million barrels in 2012. 

Investment in biofuels, largely spurred by the RFS, has led to the development of facilities like 

our 1st commercial biorefinery in Vero Beach, Florida, and KiOR’s in Columbus, Mississippi, 

which represent several hundred million dollars of investment in the United States and are poised 

to begin production of the next generation of renewable fuel from non-food feedstocks this year. 

Dozens more advanced biofuel projects are planned or under construction, illustrating the visible 

success the RFS has had in driving development of highly skilled, well-paying jobs in rural 

America. 

The “Blend Wall”: INEOS Bio firmly believes that the limits to market access for biofuels 

commonly referred to collectively as the “blend wall” represent a series of barriers contrived by 

obligated parties (4) to prevent biofuels from gaining access to the marketplace. (5) Multiple 

avenues exist for blending additional volumes of biofuel into the nation’s fuel supply. For 

instance, as the proposed rule recognizes, E15 blends are approved and ready for use, and 

production of flex fuel vehicles continues to increase. These options provide a suite of 

opportunities for the growth of the entire biofuels industry and RFS compliance. 

The Agency should encourage the development of biofuels, including E15 and higher octane 

blends of ethanol, and the engines and infrastructure to support them. In addition, EPA should 

allow the 1# RVP waiver to apply to E15 to be consistent with its current proposal for ethanol 

and butanol blends and that it currently allows for E10. This development can readily grow the 

supply of biofuels in the market and overcome the blend wall by allowing Renewable 

Identification Numbers (RINs) to truly reflect their market value. It will also help drive the 

market and encourage retailers to adopt new infrastructure. INEOS Bio is supportive of the 

proposed rule and believes the final Tier 3 rule has the potential to continue the progress of the 

biofuels industry and help alleviate the “blend wall” as described above. 

EPA should also seek to identify opportunities to grow biofuel markets, including adoption of a 

higher-octane blend as the gasoline base fuel. Reconsideration of the gasoline base fuel would 

enable engine manufacturers to optimize beneficial characteristics of higher ethanol blends in 

engine design. 

Commenter: National Corn Growers Association (NCGA)
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12-27

We also commend the agency on its recognition of the benefits of ethanol in transportation fuel, 

and its continued support for the Renewable Fuel Standard regulation, which is significantly 

reducing GHG emissions and improving energy security in the United States through the use of 

domestically produced ethanol. 

Our Response:

The emission analyses in this rule take into account impacts of the ethanol mandate in the 

Energy Independence and Security Act (EISA), on both emissions from vehicles and upstream 

sources. Impacts of ethanol on criteria pollutant and toxic emissions, as well as air quality, were 

previously addressed in EPA’s Renewable Fuel Standard (RFS2) rule. The Tier 3 standards will 

result in significant reductions in air toxics, including aromatic compounds, as indicated in 

Chapter 7 of the RIA. 

Several commenters urge EPA to use its authority under Section 202(l)(2) of the Clean 

Air Act to reduce aromatics in gasoline. Those comments are beyond the scope of the current 

rule. Further, comments related to comparison of air quality impacts of different ethanol blends 

is beyond the scope of the Tier 3 rule.

A commenter states that EPA mischaracterized ethanol as an air toxic. In EPA’s 2007 

mobile source air toxics rule (72 FR 8428, February 26, 2007) the term “mobile source air 

toxics” was used to define compounds that are emitted by mobile sources and have the potential 

to cause serious adverse health effects. The RIA makes no statements about whether ethanol is 

an air toxic of concern at environmental exposure levels.

A number of comments state that aromatics in gasoline create higher emissions of 

numerous pollutants, including PAHs and other toxics, BC, and precursors of SOA and UFPs. 

The Agency continues to research how various fuel properties and combustion processes affect 

emissions of PAHs, other toxics, BC, UFPs, and SOA precursors. A number of commenters 

urged EPA to improve the modeling of SOA in CMAQ. Commenters also stated that current 

emission measurements and models do not account for the full contribution to SOA from 

gasoline exhaust. EPA continues to improve the modeling capabilities of CMAQ. Many factors 

affect formation of secondary organic aerosols, including emissions of PAHs and other aromatic 

compounds from diesel and gasoline motor engines, as well as other SOA precursors, such as 

isoprene and α-pinene. NOx also plays an important role in SOA formation. EPA is conducting 

ongoing research to better understand relationships between fuel properties and emissions of 

aromatics and other SOA precursors, as well as their reactions in the atmosphere under different 

conditions.

Some commenters also urged EPA to encourage the use of ethanol, including by 

revisiting the greenhouse gas emissions standards and fuel efficiency standards, by extending the 

1-psi RVP waiver for E10 to E15 and butanol blends, or specifying different certification fuels. 

Discussion of similar comments can be found in Chapter 4.5.1.5 of this Summary and Analysis 

of Comments document, and are otherwise outside the scope of this rulemaking. 

12.5. Nonroad Diesel Engines
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What Commenters Said:

Commenter: Dresser Trap Rock, Inc.

The most fuel efficient engines we have operated since 1979 were the pre-Tier 1 engines. As we 

had to transition to Tier 1 engines, none of our operators wanted to ruin the new loaders as they 

were too slow, particularly at loading railcars and off road haul trucks.

With the advent of Tier 2 engines, it was exactly the same story all over again; the operators 

could not load off road haul trucks and particularly railcars with rock as quickly as they did with 

the Tier 1 engines.

Again, with the advent of Tier 3 engines, we found through observation of Tier 1 powered end 

loaders and Tier 3 powered loaders that a Tier 1 loader could make 4 passes to the Tier 3 

powered loader’s 3.

Now, you may say that there is more fuel economy and less emissions with Tier 3 engines 

relative to the Tier 1 engines, but if the operator has to run the loader at full throttle 25% longer 

to accomplish the identical task as a Tier 1, there cannot possibly be a reduction fuel 

consumption or emissions. 

Our Response:

This Tier 3 motor vehicle emissions rulemaking does not pertain to the nonroad engines 

of concern to the commenter (nonroad diesel engines are, coincidentally, also regulated by EPA 

in tiers—Tiers 1,2, 3, and 4). 

12.6. Anti-backsliding Study

What Commenters Said:

Commenter: American Petroleum Institute (API) and the Association of Fuel & Petrochemical 

Manufacturers (AFPM); Marathon Petroleum Company LP (MPC)

Anti-backsliding – EPA has not provided Congress with analyses required by legislation. We 

believe that the emissions benefits from the Tier 3 rule should be counted as offsets for the 

environmental impacts of the Renewable Fuel Standard since the RFS was effective long before 

Tier 3.

EPA has not provided Congress with analyses required by legislation. The Agency is required to 

conduct anti-backsliding studies per section 1506 of EPAct05 (draft for public comment was due 

summer 2009 and a final report was due summer 2010) and section 209 of EISA (due summer 

2009). 
Tier 3 Summary and Analysis of Comments

12-29

In letters to Charles Drevna (AFPM) and Jack Gerard (API) dated March 6, 2012, EPA 

emphasized that the Tier 3 rule is independent of this upcoming anti-backsliding study. EPA 

repeated this in a letter to Senator Inhofe dated March 19, 2012. Gina McCarthy restated this 

independence on page 113 of her answers to Senator Vitter in May 2013. 

We believe that the emissions benefits from the Tier 3 rule should be counted as offsets for the 

environmental impacts of the Renewable Fuel Standard since the RFS was effective long before 

Tier 3.

Our Response:

The anti-backsliding study is required by Clean Air Act sections 211(q) and (v) and is 

outside the scope of this rulemaking. EPA’s analysis and modeling to support the Clean Air Act 

section 211(q) and 211(v) “anti-backsliding” study is still underway. As required by Clean Air 

Act section 211(q), EPA will release a draft report for public comment before publishing it in 

final form. Thus, there will be an opportunity to review and comment on EPA’s analysis and 

conclusions.

12.7. Alternative Fuels

What Commenters Said:

Commenter: Advanced Biofuels USA (ABFUSA)

Allow Optional Renewable Higher Octane Additives: While biomass, 

cellulose/hemicellulose/pectin, (“cellulosic ethanol” in RFS2) derived ethanol is the current 

primary octane enhancing component foreseen for Higher Octane, Higher Ethanol Fuel, final 

Tier 3 regulations should provide flexibility for other biofuel derived additives provided the 

following four criteria are met: 

1. Life Cycle GHGs of the alternative additives are within 110% of industry wide life-cycle 

GHG emissions of the biomass ethanol used at the time of the introduction of the alternative 

additives. 

2. The composition of the biofuel derived fuel components do not exceed EPA or CARB, 

whichever is lower, aromatic or other fuel composition standards in effect at the time of their 

introduction.

3. The use of such fuel components would not materially effect the cost of vehicle certification 

testing procedures. 

4. The use of such fuel components would not materially effect any fuel system or engine 

components of the vehicles it was used in. 

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global); General Motors LLC (GM)

While OEMs discussed the interconnection of fuels and vehicle issues with EPA during the 

negotiations leading to the 2017 CAFE/GHG requirements, EPA declined to include fuel issues 
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12-30

in that rulemaking. However, at that time EPA gave the industry assurance that these issues 

would be addressed promptly within the Tier 3 rulemaking in order to facilitate the needed 

product changes to support the CAFE/GHG standards, as well as Tier 3 requirements. The OEMs 

are spending billions of dollars (34) on compliance with the CAFE/GHG rules and require the 

cleanest fuels possible to meet these obligations. We urge EPA to support the progress toward 

cleaner vehicles by ensuring that the proper fuels are widely available. 

To date, EPA has only agreed to propose changes to the existing sulfur market fuel standards. 

The Alliance and Global note that there are a number of other time-sensitive market gasoline 

changes that warrant federal standards and that should be addressed by EPA in a supplemental 

rulemaking. We reiterate that the regulations for engines and fuels must be integrated to ensure 

environmental progress, and to ensure that new engine designs, vehicle exhaust and evaporative 

after-treatment systems do not become stranded investments or opportunities, from a lack of 

commitment to improve fuel quality to achieve cleaner, more efficient vehicle operation.

34 - As noted in Alliance testimony for this rulemaking, according to EPA, automakers will spend about 

$15 billion in just ten years to meet the requirements of this proposed rule, and effectively remove tailpipe 

emissions from the environmental equation. As EPA further states, combined with the fuel economy and 

greenhouse gas program, this rule would bring auto investment in the vehicle emission reduction 

programs through 2025 to more than $216 billion –about 100 times the investment that the oil industry is 

being asked to make under the NPRM.

Our Response:

These comments are outside the scope of the Tier 3 rulemaking. There are already in 

place a set of regulations associated with the introduction into commerce of new fuels and fuel 

additives in keeping with our CAA responsibilities. Any other fuel standards would have to go 

through a 211(c) rulemaking process similar to Tier 3.

12.8. Detergency Requirements

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

Detergency Requirements Need Improvement: Our members support EPA’s proposed 

requirements that clarify the treatment of gasoline additives (82). However, additional regulatory 

improvements are needed with regard to detergency additives for motor vehicle fuel. 

Lowest Additive Concentration (LAC) Detergency: Due to the ability of detergents to inhibit the 

formation of engine deposits (83) and decrease emissions, the addition of detergents is required 

in the U.S. under the CAA (84). The implementing regulations (40 C.F.R. Part 80, Subpart G) 

allow refiners and marketers to meet the requirements by adding the lowest additive 

concentration (LAC) that minimizes deposits, based on tests conducted by the additive supplier 

using an EPA-defined fuel that reflects a (one-time) determination of the 65th percentile highest 
Tier 3 Summary and Analysis of Comments

12-31

value for four fuel properties (sulfur, aromatics, olefins, and T90).85 This additive concentration 

can then be used by any fuel supplier. The shortcoming of this practice is that there are fuels in 

the marketplace that produce more deposits than the 65th percentile fuel, and therefore will not 

be adequately treated to control deposits.

Automaker experience has shown that the required evaluations for fuels meeting LAC are 

insufficient to assure consistency and efficacy across the fuels marketplace for today’s nearly 

250 million vehicles. The LAC principle has resulted in gasoline refiners and marketers reducing 

the concentrations of detergent additives in their fuels by as much as half of levels observed in 

the 1990s. This degradation of detergency is shown in Figure 3 [Figure 3 can be found on p. 91 

of Docket number EPA-HQ-OAR-2011-0135-4461-A1]. The trending downward of unwashed 

gum levels (a marker for the amount of detergent additive present) suggests lower detergent 

additive doses and downgraded quality (albeit that in some newer products, lower concentrations 

can produce the same effect). At the same time, vehicle emissions and durability requirements 

have become increasingly more stringent. 

Recommendation: Auto manufacturers remain concerned about induction system deposits in 

U.S. marketed vehicles. These concerns have been raised on multiple occasions with EPA. In the 

past, the EPA was provided with data which demonstrated on-going problems with U.S. gasoline 

detergency compliance showing that the program was not effective at retail. We urge EPA to 

refocus on this issue, which has emissions impacts and should be a Tier 3-related market fuel 

issue. Because of these adverse trends, as apparent in Figure 3, EPA must assure that all fuels 

include sufficient detergent concentration. We would be happy to work with the Agency and the 

other stakeholders on a regulatory solution.

82 - 78 Fed. Reg. 29908 at 29929 (May 21, 2013).

83 - Deposits are formed within the engine and/or fuel system during normal vehicle operation over a 

period of time. Certain gasoline components such as di-olefins are relatively unstable and they thermally 

break down during engine operation, leading to formation of deposits on fuel injectors, inlet valves, and 

within the combustion chamber. Combustion chamber deposits (CCD) can result in a higher effective 

compression ratio, which then increases the need for a higher octane rated fuel. Additionally, CCDs can 

absorb and release hydrocarbons, leading to an increase in hydrocarbon emissions. See also current 

edition Worldwide Fuel Charter recommendations, available from the Alliance of Automobile 

Manufacturers.

84 - The text from the CAA requirement in Sec. 211(1) reads as follows: “Effective beginning January 1, 

1995, no person may sell or dispense to an ultimate consumer in the United States, and no refiner or 

marketer may directly or indirectly sell or dispense to persons who sell or dispense to ultimate consumers 

in the United States any gasoline which does not contain additives to prevent the accumulation of deposits 

in engines or fuel supply system. Not later than 2 years after the date of the enactment of the Clean Air 

Act Amendments of 1990, the Administrator shall promulgate a rule establishing specifications for such 

additives.”

85 - The LAC requirement is defined in 40 C.F.R. Part 80, Subpart G, Sec. 80.141(c)(3) as follows: 

“Minimum recommended concentration: (i) The lower boundary of the recommended range of 

concentration for the detergent additive package in gasoline, which the additive manufacturer must report 

pursuant to the registration requirements in § 79.21(d) of this chapter, must equal or exceed the minimum 

concentration which the manufacturer has determined to be necessary for the control of deposits in the 

associated fuel type, pursuant to paragraph (e) of this section. The minimum recommended concentration 

shall be provided to EPA in units of gallons of detergent additive package per thousand gallons of 
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12-32

gasoline or PRC, reported to four digits. This concentration is the lowest additive concentration (LAC) 

referred to elsewhere in this subpart.”

Commenter: Ford Motor Company (Ford)

Increased Detergency Requirements for Market Fuel: Gasoline additives used to protect vehicles 

from damage caused by deposits are known as detergents. Deposits are formed within the engine 

and/or fuel system during normal vehicle operation over a period of time. Certain gasoline 

components have higher boiling points, such as di-olefins, and during the combustion process, 

they thermally breakdown during engine operation, leading to formation of deposits on fuel 

injectors, inlet valves, and within the combustion chamber. Combustion chamber deposits (CCD) 

can result in a higher effective compression ratio, which then increases the need for a higher 

octane rated fuel. Additionally, CCDs allow for a medium to which liquid hydrocarbons can 

absorb and release, leading to an increase in hydrocarbon emissions. Another consequence of 

CCD is ‘carbon knock’ which can result from the mechanical interference between the piston top 

and the cylinder head. Fuel injector deposits are of particular concern because the fuel passages 

are so small that deposits can prevent normal flow of fuel, resulting in degraded driveability, 

decreased power and fuel economy and increased exhaust emissions. Intake valve deposits also 

result in reduced power, cold-start and warm-up driveability issues and increased exhaust 

emissions. 

The lowest additive concentration (LAC) regulation allows for refiners to meet the requirements 

by adding the lowest additive concentration that prevents deposits based on a selected batch 

sample from the refinery. The shortcoming of this practice is that the batch sample selected may 

be a sample representative of the “best-case” fuel formulation that results in minimal deposit 

formation. This allows obligated parties to choose an under representative sample from the 

population of fuels that the obligated party produces for the marketplace. Common practice 

results in an incorrectly calculated LAC that is then employed across all fuels produced. 

Experience has shown that fuels meeting LAC are insufficient for meeting the needs across the 

marketplace, which includes nearly 250 million vehicles. Auto manufacturers remain concerned 

about induction system deposits in U.S. marketed vehicles. Despite continued messaging about 

the need for more stringent detergency requirements, the LAC program has received no 

modifications since its inception, over two decades ago. Since the Tier 3 program acknowledges 

that “vehicles and fuels [are] a system,” the detergency requirements of fuels must be adjusted to 

ensure adequate deposit control protection for all finished gasoline sold in the U.S. market, so 

that meeting the increased durability requirements of Tier 3 can be assured. 

Recommendation: Ford supports the Alliance’s request to require all fuels meet deposit control 

tests such that enough detergents are added to meet the needs of the lowest quality product batch 

rather than just the cleanest stream. Ford supports the Alliance’s request that the Lowest 

Additive Concentration (LAC) requirement for gasoline detergency be eliminated and an 

appropriate rule be introduced in its place. 

Our Response:
Tier 3 Summary and Analysis of Comments

12-33

EPA’s consideration of whether changes to the gasoline deposit control program are

needed is beyond the scope of the Tier 3 rule. There is no data available that indicates the 

current levels of deposit control protection are insufficient to support the maintenance of the Tier 

3 vehicle emissions standards in-use. EPA continues to be open to working with industry to 

evaluate the potential emissions benefits of implementing updated deposit control requirements. 

Data on the potential emissions benefits is vital to this evaluation. As discussed in Chapter 6.1.4

of this Summary and Analysis of Comments document and Section VI.A.4 of the preamble to the 

Tier 3 final rule, we are finalizing provisions to accept “Top Tier” deposit control test data in the 

certification of deposit control additives.

12.9. Methylcyclopentadienyl Manganese Tricarbonyl (MMT)

What Commenters Said:

Commenter: Alliance of Automobile Manufacturers (Alliance) and Association of Global 

Automakers (Global)

EPA Should Undertake Regulatory Review of MMT/Metallic Additive: All vehicle 

manufacturers have long opposed the use of any metallic based additive in gasoline, including 

compounds of iron, silicon, phosphorus, and manganese such as MMT (methylcyclopentadienyl 

manganese tricarbonyl). Their use results in damage to engine parts and emissions control 

components. 

Manganese-based additive can be used as an octane enhancer for gasoline; however, when 

combusted in an internal combustion engine, manganese is transformed into manganese oxide 

particles. As documented in numerous studies and scientific papers, the prolonged use of 

gasoline with manganese-based additives results in such particles contributing to the plugging 

and failure of catalytic converters, which have been used on vehicles for decades to control 

emissions of carbon monoxide, hydrocarbons, and oxides of nitrogen. 

Over the years, catalytic converter technology has improved dramatically, with conversion 

efficiencies today of more than 95%, to keep pace with increasingly more stringent vehicle 

emission standards. The residual amount, technically speaking, corresponds to the vehicle’s 

tailpipe emission level. As emission standards become more stringent, this residual amount 

becomes even smaller. For today’s advanced equipment, such plugging and failure problems –

which reduce conversion efficiencies – are especially problematic. Degradation and failure of 

catalytic converters cause vehicles to have higher emissions, degrading air quality and 

potentially causing vehicles to exceed emissions standards, and to fail state/local vehicle mission 

inspections. Damaged catalytic converters are very expensive to replace.

The manganese oxide particles also cause deposits to build up on internal engine parts, spark 

plugs, and oxygen sensors. This can also cause vehicle performance and emission problems, 

including loss of fuel economy and illumination of dashboard “check engine” lights, and 

premature and additional vehicle repairs for consumers. 
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12-34

Because of these risks, all major manufacturers selling vehicles in the U. S. recommend in their 

vehicle owner manuals that any fuel containing manganese-based additives NOT be used in 

today’s vehicles. 

Metallic additives, including those with manganese, are prohibited in Federal reformulated 

gasoline (RFG), which represents about one-third of the U.S., non-California gasoline pool and 

is prohibited under State law in all gasoline sold in California. EPA allows the use of MMT in 

non-RFG gasoline at a maximum of 1/32 gram Mn as MMT/gallon (80) following a long 

stakeholder controversy beginning that had resulted in an earlier EPA ban of MMT. 

For a number of years there have been no MMT or other metallic additives detected in the annual 

(Summer/July and Winter/January) Alliance of Automobile Manufacturers North American Fuel 

Surveys for the U.S. In the past several years, however, in several States, including Nevada and 

neighboring states, and also in the Southeast, there has been renewed local interest in using 

MMT additive, raising concerns among various stakeholders. An issue so fundamental for all 

vehicles is not suited for State by State response – the same costly and inconsistent dynamic 

which led to CAA additive provisions and a federal EPA standard in the first instance. 

It would be appropriate for EPA to again consider a comprehensive prohibition for metallic 

additives for any gasoline sold in the US, at the earliest possible time. EPA should formally 

consider studies and data that have become available on adverse effects of MMT on vehicle 

equipment since EPA’s last action, for example, the findings in the 2008 Sierra Research Report 

“Impacts of MMT(R) Use in Unleaded Gasoline on Engines, Emissions Control Systems, and 

Emissions (copy attached as Appendix 6 to these comments) (81). 

Many other organizations are also on record opposing the use of manganese-based gasoline 

additives for both technical and health reasons, including the Manufacturers of Emission 

Controls Association, The International Council for Clean Transportation, Truck and Engine 

Manufacturers Association, and the National Resources Defense Council. See also, the current 

4th edition and pending 5th edition of the Worldwide Fuel Charter, available from the Alliance 

of Automobile Manufacturers website (www.autoalliance.org). 

CAA §211(c) addresses EPA’s ability to prohibit or limit the sale of fuel additives that are 

already approved if they will “impair to a significant degree the performance of any emission 

control device or system which is in general use.” The Agency should undertake an updated 

evaluation of MMT use as a gasoline additive. 

Recommendation: EPA should promptly initiate a formal review of MMT use with notice and 

comment to prevent putting all gasoline engines and emission reductions at risk from metallic 

additives. 

80 - See http://www.epa.gov/otaq/regs/fuels/additive/mmt cmts.htm; and 65 Fed. Reg. 44775 (July 19, 

2000).

81 - Sierra Research, Report No. SR2008-08-01, August 29, 2008, prepared for the Canadian Vehicle 

Manufacturers’ Association and Association of International Automobile Manufacturers of Canada. Also 

available from the Alliance website under Fuels, www.autoalliance.org.
Tier 3 Summary and Analysis of Comments

12-35

Commenter: American Honda Motor Co., Inc.

Honda wishes to voice strong support for the recommendation made in the joint Association of 

Global Automakers-Alliance of Automobile Manufacturers comments regarding the issue of 

MMT and other metallic fuel additives. Honda sees an urgent need for, and strongly 

recommends, that EPA once again consider a comprehensive prohibition of metallic additives for 

any gasoline sold in the United States.

Commenter: Ford Motor Company (Ford)

Elimination of the use of Metallic Additives in Market Fuel: The use of manganese (also known 

as methylcyclopentadienyl manganese tricarbonyl or MMT) began with the phase-out of leaded 

fuel as it is marketed as an octane booster. When used in gasoline as an octane booster, MMT 

does not burn completely, as does its ethanol counterpart. Instead, the manganese in MMT reacts 

during the combustion process to form solid manganese oxide particles that are reddish-brown in 

color. These particles form deposits in the engine as well as accumulate on the front inlet face of 

catalytic converters and throughout the exhaust system. Manganese oxide deposits also appear 

on engine components including deposits on spark plugs (leading to misfire, which leads to 

increased emissions, increased fuel consumption and poor performance) and on the oxygen 

sensor (causing malfunction and again increasing emissions and resulting in poor performance). 

Additionally, manganese oxide deposits on the catalytic converter cause plugging of the catalyst, 

increased back pressure, poor vehicle operation and increased fuel consumption, as well as 

increased tailpipe emissions due to diminished emission control function.

In order to meet the more stringent emissions standards of Tier 2, the vast majority of vehicle 

manufacturers implemented the use of high density close coupled catalysts (HDCC) which 

contain more catalyst cells per unit area than older technology catalysts. The increase in the 

number of cells per unit area results in an increase in the overall catalytic active surface area and 

also decreases the actual size of each individual channel of the substrate. This advanced 

technology allows for reduced time needed for the catalyst to reach operating temperatures, but 

due to the smaller channel sizes, it also results in increased susceptibility to front-face catalyst 

blockage from manganese oxide deposits. Many manufacturers cite that no other technologies 

exist that are as effective as HDCC catalysts. Further, the need to meet the more stringent 

emissions standards of the future will drive the catalysts closer to the engine, resulting in 

increased catalyst inlet and front-face temperatures. With the inevitable manganese oxide 

deposits that the combustion of MMT in gasoline creates, these HDCC catalysts can be rendered 

useless for emissions control and can create vehicle performance issues once contaminated. 

The following images, extracted from the 2008 Sierra Research report (9), illustrate the typical 

severity of the plugging observed on a catalyst exposed to MMT. The first image (Figure 1) is a 

catalyst obtained from a vehicle operated with MMT-free fuel for approximately 100,000 miles 

while the second image (Figure 2) shows a catalyst from a vehicle after accumulating only 

40,000 miles using gasoline containing MMT. The considerable amount (almost 95% of the 

catalyst is covered) of manganese oxide deposits in Figure 2 demonstrates the severity of 

manganese-based deposits coating catalysts (and therefore rendering them useless). Furthermore, 

the additional emissions durability requirements of 150,000 miles will demand that vehicles do 
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not use fuel which may damage the catalyst. Thus, considering the known abilities of MMT 

containing gasoline to damage vehicle catalysts, MMT and similar metallic additives must be 

prohibited from market fuels. 

Recommendation: Ford continues to remain opposed to the use of any metallic based gasoline 

additive (lead, iron, silicon, phosphorus, and manganese) and strongly supports the Alliance 

comments which ask for the EPA to perform a regulatory review of the use of metallic additives 

and manganese (also known as MMT). Ford strongly supports the Alliance comments submitted 

in regard to MMT and seconds their recommendation for the ban of manganese based gasoline 

additives. 

9 Sierra Research Inc. “Impacts of MMTR Use in Unleaded Gasoline on Engines, Emission Control 

Systems, and Emissions,” August 29, 2008.

Our Response:

Comments on metallic fuel additives are outside the scope of this Tier 3 rulemaking.

12.10. Other

What Commenters Said:

Commenter: Peoples Republic of China

We noticed that in the measurement of limits of evaporative pollutants, Remote Sensing Device 

(RSD) testing technology is adopted, while in the measurement of PM emission level, a new FTP 

PM testing standard is adopted. In order to achieve the target specified by USA’ Tier 3 emission 

standard, as specified in Article 11.3 of TBT Agreement, the Proposer shall grant other 

Members, especially the developing country Members, guidance on the testing technology and 

technical resistance, help them fully apprehend new testing technology and improve their 

production process scientifically to accommodate themselves to new technical requirement in 

time. 

Environment protection is a common responsibility to be borne by all countries. Superior or 

inferior environment quality in any region is just partial and temporary. With a view to realize 

effective environmental protection, we believe that in accordance with Article 2.6 of TBT 

Agreement, WTO Members that are advanced in science and technology shall, giving priority to 

appropriate international standardizing bodies, play a full part in and promote preparation of 

international standards, lead actively the world to take concerted actions to realize 

comprehensive and scientific environmental protection. 

Commenter: Algenol Biofuels Inc.

The national policy particularly favors biofuels such as Algenol’s ethanol which has an 

especially low life-cycle output of greenhouse gas emissions. A life-cycle analysis conducted by 
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the company along with the Georgia Institute of Technology’s Strategic Energy Institute 

demonstrates at least a 60%, and in many scenarios 80%, reduction in greenhouse gas emissions 

when compared to regular gasoline. (See Luo, Hu, et al, “Life Cycle Energy and Greenhouse 

Gas Emissions for an Ethanol Production Process based on Blue-Green Algae,” Environmental

Science & Technology, 2010, 44 (22), pp. 8670-8677.) 

Commenter: Private Citizen

Subsidize electric vehicles instead! When they become less costly and services more widely 

available, people will easily change to electric.

Commenter: Private Citizen

This may also decrease the emission of cadmium which is present in all combustion but not 

measured adequately since lead was removed from gasoline. All the problems associated with 

exposure to motor vehicle emissions can occur with cadmium exposure alone. Cadmium lowers 

25 OH vit D3. Low levels are found in all serious diseases. This phenomenon has occurred since 

lead was removed from gasoline. Lead blocks cadmium uptake and lead chloride formed a 

complex with cadmium fumes making it less bioavailable. Blood, urine, and hair levels of 

cadmium do not necessarily reflect cadmium exposure and toxicity because if there is not 

sufficient metallothionein to bind it, cadmium quickly disappears from blood into the lining cells 

of blood vessels and into endocrine cells and the choroid plexus. 

These new standards need to address cadmium as well by developing new technologies to look at 

cadmium fumes from motor vehicle emissions. 

It is really necessary to re-examine the effects of lead in gasoline. Lead is the lesser toxin. By 

removing lead from gasoline RICE which contains arsenic is more toxic. Lead, cadmium and 

arsenic block each other’s toxicity while cadmium and arsenic are synergistically toxic. 

We know that these new standards are highly cost-effective – costing about a penny per gallon of 

gasoline. In return, Americans would save over $10 billion per year on health care costs by 2030. 

They would save even more if cadmium were addressed. 

Commenter: Open Joint-Stock Company

Currently, we also found a way to solve the above-mentioned major environmental problems. To 

fulfill this goal, we have developed a comprehensive high-tech multi-functional devices of new 

generation for the petrochemical industry, for example, CS ‘TORNADO’. Moreover, on the 

basis of CS ‘TORNADO’, developed, such as CS ‘Mercury’ and other complex systems and 

installations for the treatment and disposal of toxic and output of toxic gases, as well as a variety 

of solid particles produced by different factories and mills of various sources of pollution. 

The main purpose of the above systems, a complete cleaning of exhaust gases and obtaining 

alternative fuel, for example, synthesis gas, and other gas mixtures for combustion of 

hydrocarbon fuel, and for cleaning of gases. The use of CS ‘TORNADO’ for crude oil and other 
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chemicals, will raise the refining and petrochemical sector in Latvia to a new level of high-tech 

development and production standards. 

We offer you a brief look at some key features and specifications of CS ‘TORNADO’, which 

will be applied in the 21st century, and possibly the 22nd century. Next, read the applications ... 

(See Appendix 4).

Commenter: Robert Bosch GmbH, Gasoline Systems, Germany

Also it needs to be assured the levels for silicone compounds from biomethane originating from 

waste or sewage sludge are fixed at 0,1 mg/m3 to ensure proper working of exhaust gas treatment 

systems. 

Commenter: Private Citizen

I would like to add one thing. Please create a stop pollution hotline. Create a 1- 800-CLE-ANUP 

hotline so that drivers and pedestrians may report vehicles that seem to be polluting, whether it is 

from tail pipes or uncovered loads of materials being transported. Let such a violation result in 

the situation being improved and heavy fines being collected. Perhaps the fines could be used to 

reimburse hospitals that work on asthma patients. Although you will receive this message from 

other citizens who care about the atmosphere, I will leave it in the letter. The facts are important 

and clearly stated. Let’s not emulate the pollution in China.

Commenter: Children’s Environmental Health Network (CEHN)

EPA should issue a public annual compliance “report card” on each automaker. This level of 

transparency is in the spirit of right-to-know laws and facilitates informed consumer choices.

Commenter: Textile Industries, Inc.

I am admittedly not a scientist or an expert on sequestration of greenhouse gases, but due to my 

profession, I am required to keep myself apprised of all things having to do with our 

environment. As such, I can say with some confidence that there is enough scientific evidence 

now to show that air pollution, and especially greenhouse gases, are mainly responsible for 

global warming, also known as climate change, in the world we currently live in. And this is the 

only world we’ve got.

Some scientific evidence indicates that we have perhaps already passed a tipping point beyond 

which we cannot prevent the domino effect of increased greenhouse gases being released from 

beneath the ocean bottoms in the form of methane, which is worse even than the CO2 which has 

been primarily responsible for climate change until now.

Commenter: Thomas Jefferson University Hospital
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I have spent over 150 hours a year for the last 20 years as a volunteer in trying to decrease the 

burden of asthma on children in this city and State. I’ve been an advocate on many levels. I was 

one of the founding members of the Pennsylvania Allies Against Asthma, now deceased because 

of funding, but a great organization in its time. And I’m now the Medical Director of the 

Pennsylvania Asthma Partnership.

Why am I spending all this time? That’s about three weeks of my year that I spend doing this, 

and, trust me, no one pays me for it. Well, I do it because asthma is the most common cause of 

medical school absence nationally, and, in Philadelphia, which has an even larger burden, it 

reflects almost half the days lost in school to medical reasons. I do it because it’s the most 

common reason that people from our emergency rooms are admitted to the hospital.

But as a group, we can cause an even more important effect, and that’s the effect of diesel 

vehicle’s emissions on asthma. If you live on a street that has lots of trucks and buses going 

down it, your chances of having either chronic or acute asthma is almost double that of someone

who lives in the same city a few blocks away on a quiet street that doesn’t have trucks on it.

So we know that truck emissions, even though the diesel vehicles are much cleaner than they 

ever were, we know we can do more. And we can, once we have a problem, solve it. When I 

started in pediatrics 34 years ago, the average lead in a child in Philadelphia was a 20 

micrograms per deciliter. It is now a three. There’s no safe level of lead in children, but three is 

a lot better than 20.

In this same way, if we can actually stop trucks and buses from idling, if we can install systems 

that turn them off when they come to a red light, if we can take the city light system, stop light 

system, and get them to be coordinated so there are less stops and less traffic jams, and on a few 

streets put some traffic officers to stop traffic jams from happening, we can reduce the number of 

children I see in the ER. We can reduce the number of children admitted, and we can have 

children go to school a lot more days than they’re going to school right now. And from the 

world of pediatrics, we would thank – all of us would thank you if you could do anything to help 

us out on that.

Commenter: National Corn Growers Association (NCGA)

We also provide comments on EPA’s stated plan to develop an assessment of the health effects 

of exposure to ethanol in Appendix A. 

The proposed rule indicates that: EPA is planning to develop an assessment of the health effects 

of exposure to ethanol, a compound which is not currently listed on EPA’s IRIS database. 

Extensive health effects data are available for ingestion of ethanol, while data on inhalation 

exposure effects are sparse. In developing the assessment, EPA is evaluating pharmacokinetic 

models as a means of extrapolating across species (animal to human) and across exposure routes 

(oral to inhalation) to better characterize the health hazards and dose-response relationships for 

low levels of ethanol exposure in the environment. 
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The potential for health effects due to ethanol exposures associated with its use in motor vehicle 

fuel were extensively evaluated a number of years ago by several organizations. The California 

EPA, (21) the Health Effects Institute (HEI), and several other groups evaluated ethanol as a 

replacement when problems associated with the gasoline additive, methyl tertiary-butyl ether 

(MTBE), became apparent. All these analyses have concluded that the exposures to ethanol from 

its use as a motor vehicle fuel are very unlikely to have any adverse consequences. 

Although it is well established that relatively high doses of ingested ethanol and high blood 

levels of ethanol associated with the consumption of alcoholic beverages have toxic effects in 

humans, the amount of alcohol absorbed from the low doses of environmental ethanol is 

extremely small in comparison. In fact, the small doses that may be experienced are the same 

order of magnitude as naturally-occurring levels of ethanol in blood. In addition, ethanol is 

readily degraded in the environment, both in air and in water so it will not accumulate to levels 

of concern. These findings provide strong evidence that environmental exposures to ethanol will 

have no adverse health impact. 

The California analysis included detailed modeling of the ambient ethanol exposures for several 

fuel variations and comparisons of the results to levels of concern developed by the Office of 

Environmental Health Hazard Assessment (OEHHA). The modeled incremental ambient ethanol 

concentrations were in the range of 5 to 100 ppb. The OEHHA health protective concentration 

(HPC) was 53 ppm. It was derived from a study that reported a lowest effect level of 5300 ppm 

for sensory irritation from inhaled ethanol in normal healthy subjects. OEHHA applied an 

uncertainty factor of 100 to derive the 53 ppm (53,000 ppb) health protective level. 

When the modeled ambient levels were compared to the acute and chronic non-cancer HPCs, 

OEHHA concluded that modeled concentrations are at least 500-fold below the HPCs. This led 

OEHHA to conclude that health effects due to ethanol exposure are not expected to occur. 

OEHHA also evaluated the potential for cancer and concluded that there is no evidence that 

ethanol is carcinogenic via the inhalation route even though heavy consumption of alcoholic 

beverages is known to be associated with increased incidences of some cancers, including those 

of the oral cavity and of the liver. OEHHA noted that ethanol was considered by the Proposition 

65 Science Advisory Panel, who reviewed the evidence as to the carcinogenic and cocarcinogenic effects of ethanol in humans and animals. The Panel specified the listing of 

“alcoholic beverages, when associated with alcohol abuse” as carcinogenic in July 1988. The 

1999 OEHHA report followed this assessment in concluding that, whereas high levels of chronic 

exposure to ethanol are carcinogenic to humans, the levels of ethanol predicted to occur in air or 

water as a result of its use in gasoline were unlikely to result in a cancer risk to the exposed 

population. 

The Health Effects Institute carried out a thorough review of the information on exposures to and 

health effects from various oxygenates including ethanol. In agreement with CalEPA, the HEI 

Committee concluded that it was unlikely that the low exposures to ethanol would cause any 

health effects. For example, the Health Effects Institute review included estimates of incremental 

blood level increases for two refueling exposure: a typical refueling scenario, 1 ppm for 3 

minutes, and an extreme exposure scenario, 10 ppm for 15 minutes. The HEI Panel concluded: 
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Even the extreme scenario is expected to result in an incremental blood level that is insignificant 

compared with the endogenous blood levels resulting from normal metabolism. 

The HEI Committee concluded that in exposure scenarios encountered by the general public, it is 

unlikely that an increase in ethanol blood levels will be measurable and that health effects from 

exposure to ambient levels of ethanol are unlikely because endogenous blood ethanol levels are 

not predicted to increase significantly from inhaling ethanol in fuel. 

In addition to the findings of the extensive reviews by HEI, CalEPA and others, the U. S. EPA 

has not considered ethanol as an air toxic of concern in its recent evaluations and rulemakings. 

For example, the Agency did not include ethanol in a group of 177 air toxics compounds that 

were evaluated in the most recent National-Scale Air Toxics Assessment. Ethanol was 

not explicitly considered in the February 26, 2007 Mobile Source Air Toxics Rulemaking. When 

EPA first announced its interest in removing MTBE, the Agency understood that.

Given that ethanol is formed naturally in the body at low levels, inhalation exposure to ethanol at 

the low levels that human are likely to be exposed are generally not expected to result in adverse 

health effects. 

Although the EPA IRIS database does not currently include ethanol, there has been a 1,000 ppm 

occupational standard for ethanol for decades. The 1,000 ppm 8-hour time-weighted average 

standard was set to provide a no-effect level for irritation in the occupational setting. An 

additional relevant study is available. Nadeau, et al., 2003 specifically evaluated possible 

neuromotor effects of six-hour exposures to 0, 250, 500, and 1,000 ppm ethanol to healthy nonsmoking adult males in a controlled environment exposure chamber. Nadeau et al. report no 

significant differences in body sway, hand tremor, or reaction time between exposed and nonexposed conditions. In addition, ethanol was not detected in blood or in alveolar air when

volunteers were exposed to 250 and 500 ppm. At 1,000 ppm, the blood alcohol concentration 

was 0.4 mg/dl. For comparison, the legal limits for drivers are usually 80 to 100 mg/dl and the 

peak blood alcohol for an adult male consuming a typical alcoholic beverage containing 12 g of 

alcohol is on the order of 25 mg/dl. Given the extremely low doses of alcohol from inhalation of 

ambient ethanol, the health impacts of ethanol should not be a serious concern in the Tier 3 

Rulemaking. 

Our Response:

These comments are all outside of the scope of the Tier 3 rulemaking.