Deferral for CO2 Emissions from Bioenergy 

and Other Biogenic Sources under the 

Prevention of Significant Deterioration (PSD) 

and Title V Programs

Summary of Public Comments and Responses

U.S. Environmental Protection Agency

Office of Air and Radiation

Washington, DC 20460

June 28, 2011
[This page intentionally left blank.]
Table of Contents

i

Table of Contents

Page

1.0 Introduction..........................................................................................................................1

2.0 Carbon Cycle Dynamics Background and Conclusions......................................................8

2.1 Cycling of Carbon Between Plants and the Atmosphere........................................ 8

2.2 Carbon Neutrality of Biomass ................................................................................ 8

2.3 Treatment of Biogenic Carbon Emissions in the U.S. GHG Inventory................ 11

2.4 Accounting for Carbon Stocks on Land in the U.S. GHG Inventory ................... 12

2.5 Distinction Between Biogenic and Fossil Carbon Dioxide Reservoirs................ 13

2.6 Distinction Between Biogenic Carbon Dioxide that is Natural versus 

Anthropogenic....................................................................................................... 13

3.0 PSD, Title V, and Tailoring Rule Background..................................................................15

3.1 Tailoring Rule Rationale and Requirements......................................................... 15

3.2 Tailoring Rule Applicability Thresholds.............................................................. 17

3.3 March, 2011 Updated Permitting Guidance ......................................................... 18

4.0 Recent Actions/Procedures................................................................................................20

4.1 National Alliance of Forest Owners (NAFO) Petition ......................................... 20

5.0 Consistency Among Programs...........................................................................................23

6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule......................25

6.1 Affected Industries................................................................................................ 25

6.2 Meaning of “Biologically-Based Material” .......................................................... 29

6.3 Meaning of Preamble Terms “Bioenergy and Other Biogenic Sources” or 

“Biogenic CO2 Emissions” ................................................................................... 29

6.4 Open-Loop Biomass ............................................................................................. 30

6.5 Wastewater Treatment CO2 .................................................................................. 31

6.6 Co-firing Fuel Mixtures........................................................................................ 32

6.7 Municipal Solid Waste Considerations................................................................. 33

7.0 Pollutants Included in Deferral ..........................................................................................35

7.1 Non-CO2 GHG and Non-GHG Pollutants............................................................ 35

7.2 Fugitive Emissions................................................................................................ 36

8.0 Duration of Deferral and Permitted Activities During Deferral ........................................38

8.1 Deferral Start Date ................................................................................................ 38

8.2 Permanent Exemption........................................................................................... 39

8.3 Three-Year Deferral Period .................................................................................. 40
Table of Contents

ii

8.4 Scientific Examination.......................................................................................... 44

8.5 Notice and Comment Rulemaking........................................................................ 50

9.0 BACT During the Deferral ................................................................................................51

9.1 Disagreement that Use of Biogenic Fuels is BACT ............................................. 51

9.2 Alternative BACT Considerations Other than Carbon Neutrality........................ 53

10.0 Facilities Permitted During Deferral..................................................................................55

10.1 Regulatory Uncertainty......................................................................................... 55

10.2 Permitting Decisions Made During Deferral Should Hold................................... 60

10.3 Permits Issued During Deferral Should Not be Grandfathered ............................ 62

10.4 EPA Should Issue a Moratorium on Major Biogenic Projects During Deferral... 62

11.0 Rationale and Legal Justification for Interim Deferral......................................................65

11.1 Applicability of Major Permitting Programs to Biogenic CO2............................. 65

11.2 Permitting is Required .......................................................................................... 74

11.3 Permitting is Not Required ................................................................................... 81

11.4 Authority to Exempt de minimis Emissions.......................................................... 83

11.5 De minimis Authority Does Not Apply ................................................................ 85

11.6 De minimis Authority Applies.............................................................................. 93

11.7 Potential for Some Biomass Feedstocks to Have a De minimis Impact on Carbon 

Levels in the Atmosphere ..................................................................................... 93

11.8 Administrative Burdens of Permitting Projects Involving Biogenic CO2 ............ 96

11.9 Applying the Tailoring Rule Rationale for Biomass.......................................... 102

11.10 Tailoring Rule Phase-in Approach is Inappropriate .......................................... 108

11.11 Supports Tailoring Rule Phase-in Approach ...................................................... 108

11.12 Subjecting Biogenic CO2 Emissions to Permitting may be Counterproductive 

because it could Discourage Utilization of the Biomass Feedstock as Fuel....... 109

11.13 EPA Should Not Promote Biomass Use ............................................................. 113

12.0 Mechanism for Deferral and State Implementation.........................................................123

12.1 Implementing “Subject to Regulation” Definition ............................................. 123

12.2 Public Health and the Environment .................................................................... 125

12.3 Consistency of Deferral Regulations Amongst the States.................................. 126

12.4 Effect of Regulating GHG through NSPS .......................................................... 127

12.5 Effect of the Deferral when Co-fired Feedstocks or Mixed Fuels...................... 127

12.6 State Numbers of Sources, Resource Constraints, and Preferences ................... 128

13.0 Calculation Methods During Deferral .............................................................................133

13.1 Methods for Determining Biogenic CO2 Emissions (general) ........................... 133
Table of Contents

iii

13.2 Methods for Determining Biogenic CO2 Emissions (mixed fuels) .................... 134

14.0 Interim Guidance for Biogenic CO2 Sources Under PSD Review ..................................136

14.1 Interim Guidance to Address Biogenic CO2 Sources Under PSD Review......... 136

14.2 Guidance Should be Expanded ........................................................................... 139

14.3 Agree BACT is Biomass..................................................................................... 140

14.4 Disagree BACT is Biomass................................................................................ 141

14.5 Biomass Fuels Alone .......................................................................................... 143

14.6 Step 4 - Energy, Environmental, and Economic Impacts................................... 144

14.7 Step 4 - Environmental Impacts.......................................................................... 145

14.8 Step 4 - Economic Impacts................................................................................. 147

14.9 Step 4 – Energy Impacts..................................................................................... 147

15.0 Accounting Approaches...................................................................................................149

15.1 Reconciling Accounting Systems: Facility-based Emissions and Land-based 

Sequestration....................................................................................................... 149

15.2 Complexity in Accounting for Land-based Sequestration.................................. 151

15.3 General Principles............................................................................................... 157

15.4 Case-by-Case Analysis ....................................................................................... 162

15.5 Categorical Exclusion ......................................................................................... 163

15.6 Contingent Exclusion.......................................................................................... 164

15.7 Feedstock-based Approach ................................................................................. 165

15.8 Whole Trees........................................................................................................ 168

15.9 Wood Residues................................................................................................... 169

15.10 Future Market Demand for Other Biomass Crops.............................................. 169

15.11 Biological Decomposition .................................................................................. 170

15.12 Biogas Combustion............................................................................................. 171

15.13 Biogenic Fraction of MSW................................................................................. 172

15.14 Open-loop Biomass............................................................................................. 173

16.0 Forest Economics and Sustainability...............................................................................174

16.1 Forest Biomass Use is Sustainable ..................................................................... 174

16.2 Forest Economics and Markets........................................................................... 175

17.0 Environmental Justice......................................................................................................178

18.0 Miscellaneous ..................................................................................................................180

18.1 Commenters Referencing Other Commenters.................................................... 180

18.2 Commenters Incorporating Prior Comments on Other Actions ......................... 180

18.3 Administrative Requirements ............................................................................. 181
Table of Contents

iv

18.4 Other ................................................................................................................... 181

Appendix A General Public Submissions................................................................................... A-1

Appendix B Examples of Form Letters......................................................................................B-1

List of Tables

1. List of Commenters for Which Summaries Are Provided...................................................2
Acronyms and Abbreviations

v

Acronyms and Abbreviations 

ARRA American Recovery and Investment Act of 2009

BACT Best available control technology

BAU Business as usual

CAA Clean Air Act

CARB California Air Resources Board

CFI Call for Information

CFR Code of Federal Regulations

C/LNG Compressed/liquefied natural gas

CH4 Methane

CO Carbon monoxide

CO2e Carbon dioxide equivalent

DOE U.S. Department of Energy

EDF Environmental Defense Fund

EGU Electrical Generating Unit

EIA Energy Information Administration

EIS Environmental Impact Statement

EPA U.S. Environmental Protection Agency

EU(-ETS) European Union (Emission Trading Scheme)

FIA Forest Inventory & Analysis

FIP Federal Implementation Plan

FLRA Federal Labor Relations Authority

FSC Forest Stewardship Council

FR Federal Register

FTC Federal Trade Commission

GHG Greenhouse gas(es)

GWP Global warming potential

IPCC Intergovernmental Panel on Climate Change

lb Pound(s)

LCFS Low Carbon Fuel Standard

LFG(TE) Landfill gas (to energy)

LLHWP Long-lived harvested forest products

LMOP Landfill Methane Outreach Program

LULUCF Land use change and forestry

MACT Maximum achievable control technology

MM Million
Acronyms and Abbreviations

vi

MMSCFD Million metric standard cubic feet per day

MSW Municipal Solid Waste

MW(H) Megawatt (hour)

NAAQS National ambient air quality standards

NAFO National Alliance of Forest Owners

NAICS North American Industrial Classification System

NCASI National Council for Air and Stream Improvement, Inc.

NMOC Non-methane organic compound(s)

NOX Nitrogen oxides

N2O Nitrous oxide

NRDC National Resources Defense Council

NSPS New source performance standards

NSR New Source Review

OMB Office of Management & Budget

PM Particulate matter

POTW Publicly Owned Treatment Works

PSD Prevention of Significant Deterioration

RES Renewable Energy Standard

RFS(2) Renewable Fuel Standard (2)

RGGI Regional Greenhouse Gas Initiative

RPS Renewable Portfolio Standard

SAB

SIP

Science Advisory Board

State Implementation Plan

SO2 Sulfur dioxide

TDF Tire-derived fuel

UNFCCC United Nations Framework Convention on Climate Change

USDA United States Department of Agriculture

USFS United States Forest Service

USGCRP United States Global Change Research Program

VOC Volatile Organic Compound(s)

WTE Waste to energy
1.0 Introduction

1

1.0 Introduction

This document provides responses to public comments on the U.S. Environmental Protection

Agency’s (EPA’s) March 21, 2011 proposed “Deferral for CO2 emissions from Bioenergy and 

Other Biogenic Sources under the Prevention of Significant Deterioration (PSD) and Title V 

Programs” (76 FR 15249). EPA received comments on this proposal via mail, e-mail, facsimile, 

and the web site at http://www.regulations.gov. Additionally, EPA conducted a public hearing to 

allow the public to provide oral testimony on the proposed rule. Copies of the public hearing

transcript and all comment letters submitted to the docket are available at the EPA Docket Center 

Public Reading Room, or electronically through http://www.regulations.gov by searching Docket 

ID EPA-HQ-OAR-2011-0083.

In light of the large number of comments received and the significant overlap between

comments, this document does not respond to each comment individually. Rather, EPA 

summarizes and provides a single response to each significant argument, assertion, and question 

contained within the totality of comments. Within each comment summary, EPA provides in 

parentheses one or more Docket ID numbers for commenters who raised particular issues. 

However, the list of commenter ID numbers is not meant to be exhaustive. EPA does not 

individually identify each and every commenter who made a certain point in all instances, 

particularly in cases where multiple commenters express essentially identical arguments. Table 1 

includes a list of commenters whose comments were included in the comment summaries. 

In some cases the same comment was submitted by multiple commenters (e.g., by submittal of a 

form letter prepared by an organization or by the commenter incorporating the comments in 

another comment letter). Rather than repeat all of these comments, EPA has included the 

comment only once and provided a list of all the commenters who submitted similar comments 

in Appendix A of this document. The general comments listed in Appendix A fit within the 

context of the significant comment excerpts included in the body of this document. Appendix B 

contains examples of the form letters.

The primary contact regarding questions or comments on this document is:

Carole Cook (202) 343-9334

U.S. Environmental Protection Agency

Office of Atmospheric Programs

Climate Change Division

Mail Code 6207-J

1200 Pennsylvania Avenue, NW

Washington, D.C. 20460

biodeferralPSD@epa.gov
1.0 Introduction

2

Table 1. List of Commenters for Which Summaries are Provided

Docket No.

EPA-HQ-OAR2011-0083- Commenter Name Affiliation

0014.1 David Reed Individual

0015.1 Kathryn Merritt-Thrasher Individual

0022 Thierry Sam Tamers Director, Beta Analytic Inc.

0023A Roger Martella Law Firm of Sidley Austin

0023B Chris Bliley Growth Energy

0023C Dave Tenny National Alliance of Forest Owners (NAFO)

0023D Matthew Thomas Coalition for Biomass Generation

0023E Navis Bermudez Southern Environmental Law Center (SELC), 

Clean Air Task Force, Conservation Law 

Foundation, Natural Resources Council of 

Maine

0023F Robert Cleaves California Biomass Energy Alliance

0023G Jamie Consuegra Natural Resources Defense Council (NRDC)

0023H Carl Ross Save America’s Forests; Buckeye Forest 

Council; Biowatch

0023I Richard Wiles Partnership for Policy Integrity (PFPI)

0023J Paula Hamel Dominion Resources Services, Inc.

0023K Cynthia Finley National Association of Clean Water Agencies 

(NACWA)

0029 Tom Kruzen Missouri Water Sentinels

0030 Ann Rogers Individual

0032 Nathan McClure Georgia Forestry Commission

0033.1 (duplicate 

of 0044.1)

Teresa Marks Arkansas Department of Environmental 

Quality (ADEQ)

0037.1 Eddie Terrill Oklahoma Department of Environmental 

Quality

0038.1 Michael Halpin Florida DEQ

0039.1 Barry Carpenter National Meat Association

0042.1 Richard Lewis Forest Resources Association

0043.1 Michael Goergen Society of American Foresters (SAF)
1.0 Introduction

3

Docket No.

EPA-HQ-OAR2011-0083- Commenter Name Affiliation

0045 Tyson Miller Green Press Initiative

0046 Dan Fink Clackamas Tree Farm Manager, Longview 

Timberlands LLC

0047.1 Leonard Peters Kentucky Energy and Environment Cabinet

0048.1 Lara Norkus-Crampton Individual

0049.1 Louise Gorenflo Tennessee Chapter of the Sierra Club

0050.1 Jeffrey Miller Treated Wood Council (TWC)

0051.1 Kevin Igli Tyson Foods, Inc.

0052.1 Traylor Champion Georgia-Pacific (GP)

0053.1 Jacqueline Kepke California Wastewater Climate Change Group 

(CWCCG)

0054.1 David Buff Florida Sugar Industry (FSI)

0055.1 Francesco Cherubini, et al. Norwegian University of Science and 

Technology

0056.1 Jim Gillingham Valero

0057.1 Adrian Miller Longview Timber Corporation

0058.1 Andrew Ginsburg Oregon DEQ

0059.1 John Skinner Solid Waste Association of North America 

(SWANA)

0060 Kristin Palecek Flambeau River Biofuels

0062.1 (duplicate 

of 0088.1)

Kerry Kelly Waste Management (WM)

0063.1 John Hendricks American Electric Power (AEP) Company

0064.1 Paul Perlwitz Nippon Paper Industries USA Co., Ltd.

0065.1 (duplicate 

of 0067.1)

Nevena Djurdjevic The Wilderness Society

0066 Shirley Nixon Individual

0069.1 Anne Gobin Connecticut Department of Environmental 

Protection (CTDEP)

0070.1 Pamela Faggert Dominion Resources Services, Inc.
1.0 Introduction

4

Docket No.

EPA-HQ-OAR2011-0083- Commenter Name Affiliation

0071.1 Mark Doumit Washington Forest Protection Association 

(WPFA)

0072.1 Mike Draper Forest Products Industry National Labor 

Management Committee

0073.1 (duplicate 

of 0134.1)

Alabama Forestry 

Association, et al.

Alabama Forestry Association, Arkansas 

Forestry Association, Empire State Forest 

Products Association, Florida Forestry 

Association, Forest Landowners Association, 

Louisiana Forestry Association, Oregon Forest 

Industries Council, Washington Forest 

Protection Association

0074.1 David Tenny National Alliance of Forest Owners (NAFO)

0075.1 Robert Bendick The Nature Conservancy

0077.1 Mark Dopp American Meat Institute

0078.1 Robert Glowinski American Wood Council (AWC)

0079.1 Shannon Broome Air Permitting Forum (APF)

0080.1 Edward Repa, Ph.D. National Solid Wastes Management 

Association (NSWMA)

0082.1 Sara Schreiner Kendall Weyerhaeuser Company

0083.1 Chris Hobson Southern Company

0084.1 Peter Wyckoff Corn Refiners Association (CRA) et al.

0085 Ed Wilusz Wisconsin Paper Council

0086.1 Bob Dinneen Renewable Fuels Association (RFA)

0087.1 Paul Noe American Forest & Paper Association 

(AF&PA)

0089.1 Robert Hunzinger Gainesville Regional Utilities (GRU)

0090.1 Cathy Woollums MidAmerican Energy Holdings Company

0091.1 Angela Marconi Delaware Solid Waste Authority (DSWA)

0092 Leonard Ornstein Mount Sinai School of Medicine

0093.1 Gregg Morris Green Power Institute

0094.1 James Capp Georgia Environmental Protection Division 

(GAEPD)
1.0 Introduction

5

Docket No.

EPA-HQ-OAR2011-0083- Commenter Name Affiliation

0095.1 Norman Fichthorn & Allison

Wood

Hunton & Williams LLP on behalf of Utility 

Air Regulatory Group (UARG)

0096.1 Tom Martin American Forest Foundation (AFF)

0099.1 Ray Arthur Fresno-Clovis Regional Wastewater 

Reclamation Facility (RWRF)

0100.1 Sam Phillips Louisiana Department of Environmental 

Quality (LDEQ)

0101.1 Kenneth Kimmell Massachusetts Department of Environmental 

Protection (Mass DEP)

0102.1 Frank Kohlasch Minnesota Pollution Control Agency

0103 Doug Duncan Duncan Tree Farm, LLC

0104.1 Meleah Geertsma, et al. Natural Resources Defense Council

0105.1 James Colman Massachusetts Department of Environmental 

Protection (Mass DEP)

0106.1 Georgia Murray Appalachian Mountain Club

0107.1 Sarah Amick Rubber Manufacturers Association (RMA)

0108.1 Richard Hamilton Ceres, Inc., et al.

0109.1 John Melby Jr. Wisconsin Department of Natural Resources 

(WDNR)

0110 Therese Vick Blue Ridge Environmental Defense League 

(BREDL)

0111.1 Joseph Seymour Biomass Thermal Energy Council (BTEC)

0112 Henry Warchol Individual

0114.1 Alice Edwards Alaska Department of Environmental 

Conservation (ADEC)

0115.1 Ingrid Brostrom Center on Race, Poverty & the Environment 

(CRPE)

0116.1 John Holladay Local Government Coalition for Renewable 

Energy

0117.1 Cynthia Finley National Association of Clean Water Agencies 

(NACWA)

0118.1 Larry Edwards Greenpeace
1.0 Introduction

6

Docket No.

EPA-HQ-OAR2011-0083- Commenter Name Affiliation

0119.1 Scot Quaranda Dogwood Alliance

0120.1 Jeff Jahnke National Association of State Foresters (NASF)

0121.1 Ernie Shea 25x’25 National Steering Committee

0122.1 Rick Holley Plum Creek Timber Company

0123.1 Carol Whitman National Rural Electric Cooperative 

Association (NRECA)

0124.1 Myra Reece South Carolina Department of Health and 

Environmental Control (SC DHEC)

0125.1 Gary Reed Arizona Chemical

0126.1 Frederick Eames Hunton & Williams on behalf of Coalition for 

Biomass Generation (CBG)

0128.1 Stacy Brown National Wildlife Federation (NWF)

0129.1 Niki Wuestenberg Republic Services, Inc.

0130.1 William Gupton Peaks & Vistas

0131.1 Bryan Bird WildEarth Guardians

0132.1 Louis Zeller Blue Ridge Environmental Defense League

0135.1 Michael Krancer Pennsylvania Department of Environmental 

Protection

0136.1 Dave Robertson Portland General Electric Company

0137.1 Frank Rambo & David Carr Southern Environmental Law Center (SELC); 

On behalf of Georgia ForestWatch & Wild 

Virginia

0138.1 Mary Booth and Richard 

Wiles

Partnership for Policy Integrity (PFPI)

0139.1 Jay O’ Laughlin University of Idaho – Moscow

0140.1 Richard McMahon, Jr. Edison Electric Institute (EEI)

0141 Cara Beth Jones Concerned Citizens of Crawford County, 

Indiana

0142.1 Joshua Marting Environmental Paper Network

0143.1 Rachel Smolker Biofuelwatch/Energy Justice Network, et al.

0144.1 Michael Cashin Minnesota Power (MP)
1.0 Introduction

7

Docket No.

EPA-HQ-OAR2011-0083- Commenter Name Affiliation

0145.1 Margaret Sheehan Biomass Accountability Project

0146 (form letter) Various Resource Management Service, LLC

Mass comment campaign (32)

0147 (form letter) Various Mass comment campaign: organization 

unknown (129)

0148 (form letter) Various Mass comment campaign: organization 

unknown (33)

0149 (form letter) Various Mass comment campaign: NRDC

(10,262)

0150.1 William Moomaw Tufts University

0166 (form letter –

Moratorium)

Various Various (see Appendix A)

0182 Karen Dorrough Individual

0216 John Miller Individual

0260 (form letter –

Biofuelwatch)

Various Various (see Appendix A)

0269 Gretchen Brewer PT AirWatchers

0275 Ellen Moyer Individual

0319 Jess Sand Re-nourish

0332 Ned Stowe Environmental and Energy Study Institute

0350.1 Ann Brewster Weeks Clean Air Task Force on behalf of Center for 

Biological Diversity et al.

0351 Joseph Wasserman CT Coalition of Environmental Justice

0354.1 Lorraine Krupa American Chemistry Council (ACC)

0355 David Mears Vermont Department of Environmental 

Conservation (DEC)

Shaded rows indicate comments from the public hearing transcript (EPA-HQ-OAR-2011-0083-0023). A letter code 

is added to the commenter number (e.g., 0023A) to delineate individual speakers at the public hearing. 
2.0 Carbon Cycle Dynamics Background and Conclusions

8

2.0 Carbon Cycle Dynamics Background and Conclusions

2.1 Cycling of Carbon Between Plants and the Atmosphere

Comment: Commenter 0032 requested that text on Page 15252, Section II.A.1 of the proposal 

be clarified. According to the commenter, “Plants contain...roughly 50% carbon by weight” is 

not entirely accurate. Plants are roughly 50% carbon by dry weight; plants are roughly 25% 

carbon by green weight.

Response:

2.2 Carbon Neutrality of Biomass

 Within the literature, percent carbon by weight is typically reported on the dry 

weight basis. The preamble language, “Plants contain...roughly 50% carbon by weight” within 

the Page 15252 Section II.A.1 of the proposed rule follows this approach, and refers to carbon 

content in dried plant material. However, to prevent confusion, dry versus wet weight carbon 

content will be clarified, where appropriate.

Comment:

• Such fuels are carbon neutral and displace use of fossil fuels; 

Multiple commenters (0015.1, 0023D, 0056.1, 0063.1, 0064.1, 0071.1, 0074.1, 

0082.1, 0083.1, 0086.1, 0087.1, 0090.1, 0091.1, 0093.1, 0095.1, 0121, 0107.1, 0111.1, 0126.1, 

0139.1, 0140.1, 0144.1, 0332) supported the conclusion that biomass is carbon neutral based on 

the premise that biomass is part of the natural carbon cycle, and does not add additional carbon 

to the atmosphere. Plants absorb CO2 from the atmosphere and combustion of this plant material 

as a feedstock merely returns this same CO2 back to the atmosphere. According to commenter 

0144.1, it is reasonable to categorize biomass utilization as a net benefit to the balance of GHG 

over the 100-year time horizon identified by the Intergovernmental Panel on Climate Change 

(IPCC) for climate change policy. Several commenters (0074.1, 0332, 0144.1) also suggested 

that the use of biogenic fuels may actually reduce atmospheric concentrations of GHG and net 

global warming potential (GWP) because:

• Use of such fuels precludes methane (CH4) emissions if the feedstock goes unused (i.e., 

undergoes decomposition which can release GHG with additional GWP, such as CH4);

and

• Use of biogenic fuels promotes expansion of forest lands by creating higher demand for 

forest products and providing market incentives to retain and expand land -use options 

which sequester carbon. 

Commenter 0090.1 noted that the direct firing of biomass may also be one of the most carbonneutral renewable generation technologies that is suitable for baseload generation operations.

Other commenters (0032, 0095.1, 0126.1) specifically focused on the carbon neutrality of forestbased fuel sources. As stated by 0126.1, if wood-producing land is continually being reforested 

for feedstocks, then each year, the atmosphere sees a net carbon emission of zero across the 

wood-producing region because the “emissions” associated with the harvest and combustion of 

one area are offset by the uptake of carbon occurring in new growth in other areas. In addition, 

commenters 0095.1 and 0032 supported carbon neutrality of forest fuels on the national scale by 

citing current congressional policy on sustainable forest management practices (0095.1) and 
2.0 Carbon Cycle Dynamics Background and Conclusions

9

referenced reports and data that demonstrate and predict the stability or increase of carbon stocks 

in U.S. forests during the past and into the future. Commenter 0095.1 went on to emphasize that 

carbon neutrality assessments at scales smaller than the national scale “are flawed and based on 

an overly narrow interpretation”. To support this statement, the same commenter (0095.1) 

referenced the Massachusetts Department of Energy Report (presumably the Manomet study) 

that focused on the status of specific trees on specific plots, and stated that the Report 

erroneously concluded that net CO2 emissions have increased because specific plots were not 

replanted. According to commenter 0095.1, the Massachusetts study included an apparent 

unrealistic assumption that absent the demand for biogenic fuels in the state, plots would not be 

harvested for other purposes. 

In direct contrast, multiple commenters supported the conclusion that biomass is not carbon 

neutral (0045, 0065.1, 0148, 0048, 0049.1, 0055.1, 0132.1, 0147, 0166, 0138.1, 0104.1, 0023G, 

0023I, 0131.1, 0023H, 0147, 0148, 0045, 0142.1, 0149, 0150.1, 0143.1, 0269). As stated by 

commenter 0055.1, CO2 molecules spend time in the atmosphere before being recaptured by 

biomass growth, and therefore contribute to global warming. In addition, many commenters 

stressed long time delays as a main reason for the lack of carbon neutrality. Commenters

(0065.1, 0104.1) highlighted the difference in time span between natural decay processes which 

may not return CO2 to the atmosphere for decades or centuries versus combustion which 

accelerates the return of CO2. Numerous commenters (0023G, 0023I, 0131.1) referenced the 

Manomet study to state that wood as a fuel will not be carbon neutral in a timeframe that is 

important in addressing climate change. “In Massachusetts, it would take 40 years of re-growth 

for the net-carbon emissions from biomass to achieve parity with emissions from burning coal 

for those same 40 years.” (0023I). Other commenters (0023H, 0023I, 0147, 0148, 0143.1, 0182, 

0275, 0065.1) cited multiple references (e.g., Manomet study, Fixing A Critical Climate 

Accounting Error) and stated that biomass is not carbon neutral because biomass combustion can 

release higher amounts of CO2 than coal combustion per unit electricity generated. Commenter 

0150.1 specifically outlined that biomass electricity is less efficient (carbon emission from 

biomass, at the time of burning, are approximately 50% greater than coal per unit electricity 

produced) because:

• the heat of combustion of wood per unit of carbon is substantially less than that of coal 

(or natural gas); 

• wood burning cannot reach the temperatures of coal or gas, and hence boiler efficiency is 

lower; and 

• much wood is burned wet or green.

Several commenters (0023I, 0104.1, and 0049.1) also expressed a concern that biomass 

combustion, which will require harvesting and burning of whole trees which is not carbon 

neutral. According to several commenters, it is inappropriate for the EPA to create incentives to 

burn biomass indiscriminately without safeguards in place (0142.1), and incentives to remove 

trees from the landscape have no place in policy designed to reduce GHG emissions (0023I). 

One of the most important actions to reduce global warming change would be to encourage more 

forest growth (0023H). Similarly, commenter 0065.1 states that claims of carbon neutrality often 

overlook the carbon lost when land is converted from a natural forest to an energy plantation. If 

left alone, living and growing trees continue to absorb carbon from the atmosphere (0131.1, 

0149, and 0049.1). In addition, the harvesting and burning of whole trees would also result in 
2.0 Carbon Cycle Dynamics Background and Conclusions

10

the loss of other important forest services including wildlife habitat, fresh air, clean water and 

places to hike and camp (0106.1, 0131.1, and 0149). 

Multiple commenters (0142.1, 0065.1, 0147, 0148, 0149, 0132.1, 0150.1, 0045.1, and 0049.1) 

disputed the carbon neutrality of biomass combustion based on the science, assumptions and 

methods behind carbon accounting systems. Commenter 0142.1 disagreed with EPA’s decision 

to ignore scientific input from the Call for Information (CFI); they believe this disregard is 

arbitrary and capricious. The commenter attached a long list of scientific studies to support their 

claims. One commenter (0132.1) also expressed a concern regarding the assumption that electric 

power produced by the combustion of biomass would displace electric power produced by coalfired and nuclear power plants, and that biomass electric power emissions could count as a credit 

against the emissions from the biomass fuel production. As posed by the commenter (0132.1), if 

the emissions of the biomass system are as large as or larger than those from a fossil-fueled 

plant, where is the benefit? 

Commenter 0150.1 noted that the IPCC methodology that accounts for carbon in the Land 

Use/Land Use Change and Forestry (LULUCF) Sector and not in the Energy Sector is 

recognized correctly in the register, but in practice carbon emissions are not credited to either 

harvesting or combustion, and therefore, biogenic carbon is assumed carbon neutral. The 

commenter stressed that many scientists, including those that developed the IPCC rules, were 

concerned with the misuse of the IPCC rules and science. Commenters 0045.1 and 0142.1 urge 

the EPA to use scientifically sound carbon accounting principles to measure biogenic emissions. 

Commenter 0269 also urges EPA not to allow industries to redefine biomass combustion 

categories so that burning tires can be considered beneficial debris clearing, or eliminating entire 

forests is to reduce risk of forest destroying fires, or clearing the youngest and oldest trees first is 

for the “good of the forest.”

Multiple commenters (0032, 0075.1, 0030, 0062.1, 0136.1, and 0319) supported carbon 

neutrality of biomass in certain circumstances. More specifically, commenter 0032 encouraged 

the EPA to avoid broad regulations that do not recognize regional differences in forest and 

ecosystem types, forest product markets, management techniques, climate, and other forest 

demographics that have significant impacts on the viability and carbon neutrality of various 

biomass feedstocks. Commenters requested that the EPA account for biomass-to-energy 

pathways that emit more CO2 than the fossil-fuel-generated energy that they would replace 

(0075.1), and to investigate the variability of biomass feedstocks on the net carbon cycle 

(providing Arundo donaxs as an example of a type of feedstock with the potential to positively 

impact the carbon cycle if used for biomass energy production) (0136.1). Commenter 0108.1 

stated that closed loop biomass, defined as any organic material from a plant that is planted 

exclusively for the purpose of being used for bioenergy, is carbon neutral and should be 

exempted. The commenter provided the example of perennial crops like switchgrass. Commenter 

0062.1 also recognized that although some forms of biomass may not be carbon neutral, energy 

from municipal solid waste combustion results in net greenhouse reductions or is carbon neutral;

municipal solid waste combustion does not post land-use change or carbon stock changes.

Commenter 0108.1 suggested that EPA develop a strategy in which the PSD and Title V 

programs take into consideration the sources of biogenic CO2 emissions and the following 

additional factors: 1) what would have otherwise happened to the biomass had it not been 
2.0 Carbon Cycle Dynamics Background and Conclusions

11

combusted, 2) how and why the biomass was grown or cultivated in the first place, and 3) how 

and what biomass is re-grown after the initial biomass harvest takes place.

Response:

2.3 Treatment of Biogenic Carbon Emissions in the U.S. GHG Inventory

 EPA recognizes the complexity of accounting for net atmospheric impact of biogenic 

emissions considering the carbon cycle. Although plants can sequester CO2 from the atmosphere 

relatively rapidly, carbon absorbed by the plants may be returned to the atmosphere at different 

rates depending on factors such as plant type and carbon pool (ie, soil C or aboveground 

biomass). Therefore, issues raised by commenters, including the time delays between 

sequestration from and release to the atmosphere, differences between feedstocks, influence of 

spatial scale, and differences in combustion efficiencies are important in the development of 

accounting methodologies and will be considered during the scientific review that will take place 

during the three-year deferral period. EPA will consider these issues in order to account for 

biogenic CO2 emissions from stationary sources in ways that are scientifically sound and 

manageable in practice.

Comment:

Another commenter (0082.1) stated that because CO2 emissions from combustion of trees/wood 

are accounted for and tracked by the national inventory in the LULUCF Sector inventory, 

counting or regulating biogenic CO2 as an emission for PSD or Best Available Control 

Technology (BACT) will, in effect, double count the CO2 emissions from wood. Commenter 

0086.1 responded to the proposal’s discussion of the incompatibility of the retrospective U.S. 

GHG Inventory with forward looking construction and permitting programs, stating that the 

Inventory’s tracking of carbon stock trends in the LULUCF Sector provides a periodic 

assessment of atmospheric CO2 levels attributable to use of biomass for energy. Commenter 

0086.1 also noted the proposal’s recognition of this use of the Inventory under discussion of the 

“contingent exclusion.” In addition, commenter 0086.1 took exception to EPA’s characterization

of the rationale for not including biogenic CO2 at the point of fuel combustion in the Inventory 

and stated that this convention is more than just to avoid double‐counting. It is useful for 

showing the carbon neutrality of biomass combustion on a national scale.

 Multiple commenters (0082.1, 0063.1, and 0086.1) agreed with the treatment of 

biogenic carbon emissions in the U.S. GHG Inventory. Commenter 0063.1 stated that EPA’s 

inventory is prepared in accordance with the IPCC guidelines, and that these guidelines treat CO2

emissions from biomass combustion as neutral. There is no reason to deviate from these wellestablished and internationally accepted accounting principles.

However, a commenter (0119.1) expressed concerns regarding the treatment of biogenic carbon 

emissions in the U.S. GHG Inventory. More specifically, the commenter stated that accounting 

for the biomass‐derived carbon impact in the LULUCF Sector and not in the Energy Sector of 

the U.S. GHG Inventory fails to distinguish between very different activities with very different 

carbon implications. Furthermore, the commenter emphasized that placing the accounting in the 

LULUCF Sector removes accountability from an arena where there is regulatory control and 

experience (air quality) and places it in an arena lacking in regulatory power and the expertise 

(land use).

Response: During the three-year deferral period, various accounting methods for the treatment 

of biogenic carbon dioxide emissions (including that used in the U.S. GHG Inventory) will be 
2.0 Carbon Cycle Dynamics Background and Conclusions

12

reviewed by the EPA and an independent scientific panel, and issues raised by the commenters 

will be considered during this review.

2.4 Accounting for Carbon Stocks on Land in the U.S. GHG Inventory

Comment:

Multiple commenters (0064.1, 0082.1, and 0139.1) had specific comments regarding forest 

carbon stock estimates. According to commenter 0082.1, forest carbon stocks, forest volume 

and harvested wood products in the U.S. have increased steadily for over 50 years, and while 

deforestation is a serious global concern, strong U.S. markets for forest products provide 

incentives to retain sustainable working forests. Commenter 0064.1 agreed that forest stocks are 

increasing in volume, specifically in Washington State. However, commenter 0139.1 stated that 

the carbon sink represented by the LULUCF sector is larger than the amount stated in the 

proposed rule (i.e., 12 percent of the average gross emissions from all other sources combined in 

the US over the same time period) because seven or eight of the state‐level estimates are 

inaccurately reported as net sources. According to the commenter, inventory data clearly show 

that these states actually functioned as sinks. The commenter provides their own analysis of U.S. 

Forest Service baseline estimates for carbon stocks in Idaho.

Commenters 0082.1 and 0032 supported the accounting of carbon stocks on land in 

the U.S. GHG Inventory. Commenter 0082.1 concurred with EPA’s stated direction in its 2010 

GHG inventory that land use categories such as forestry should apply over the entire national 

land base and that the national land base should look at the balance of flux in greenhouse gas 

emissions and carbon sequestration across all land uses. The commenter stated that these 

principles align with EPA’s Endangerment Finding where EPA specifically determined the 

geographic scope of the endangerment finding to be the entire U.S. Another commenter (0032) 

stated that Section II.A.3. of the proposal should specify that long-lived harvested forest products 

(LLHWP) are included in the accounting of carbon flux in plant biomass in the national GHG 

inventory and that temporary decreases in forest carbon stocks that result from sustainable 

harvest are not considered emissions on a one-to-one basis because LLHWP count as a carbon 

sink. 

Commenter 0050.1 agreed with EPA’s explanation of the role of biomass as a net sink for 

carbon, its finding that the U.S. has functioned as a net sink from 1990 to 2008, and that the 

LULUCF sink will continue until at least 2020.

In contrast, one commenter (0119.1) did not support the accounting of carbon stocks on land in 

the U.S. GHG Inventory. Commenter 0119.1 declared that the simple math of the U.S. GHG 

Inventory cannot account for the different carbon sink/source implications of different land uses 

like logging of endangered forests, large-scale clear cutting, widespread conversion of natural 

forests to plantations, and the ditching and draining of critical coastal wetlands. Similarly, 

Commenter 0269 stated that the Governor of Washington has called for state-level averaging in 

the accounting of CO2 release and carbon sequestration so that all the protected parklands and 

wilderness areas are added to the carbon sequestration side of the equation in attempt to balance 

the combustion side.

Response: During the three-year deferral period, accounting for carbon stocks on land at 

various scales will be included in the review of accounting methodologies by the EPA and 

scientific panel. Issues raised by the commenters will be considered during this review. 
2.0 Carbon Cycle Dynamics Background and Conclusions

13

2.5 Distinction Between Biogenic and Fossil Carbon Dioxide Reservoirs

Comment:

Commenters (0055.1, 0132.1, 0093.1, 0023G, 0030) stated that biogenic and fossil CO2 have the 

same GWP in the atmosphere. Commenters 0055.1 and 0132.1 also stated that the true GWP of 

biogenic CO2 depends on interactions with the full carbon cycle and its sinks, the oceans and the 

terrestrial biosphere, which work on different time scales. 

Multiple commenters (0015.1, 0070.1, 0078.1, 0083.1, 0093.1, 0095.1, 0063.1, 

0023J, 0052.1, 0080.1) supported the distinction between biogenic and fossil CO2 reservoirs. 

Unlike fossil fuel carbon which has long been separated from the carbon cycle and would not 

return to atmosphere in the absence of combustion, biogenic carbon is actively cycled. The mass 

of CO2 released when burning biogenic carbon is equivalent to the mass respired from the 

atmosphere during the recent life of the biogenic fuel and equivalent to that which would 

otherwise be returned to the atmosphere by other natural processes. In addition, commenters 

(0023J) concurred with EPA’s statement that there is a significant difference in the length of 

time required to replenish the reservoirs where the carbon is stored. 

Multiple commenters (0030, 0023G, 0132.1) did not support the distinction between biogenic 

and fossil CO2 reservoirs. Commenter 0030 explained that there does not appear to be any 

viable legal basis for treating CO2 emissions from biomass differently from other CO2 emissions, 

because the Tailoring Rule explicitly states that “all carbon counts” in determining whether a 

stationary source is major. Commenters 0023G and 0319 also pointed out that trees are just like 

coal or other fossil fuels, in that they both burn and release carbon that has accumulated over 

long periods of time. Commenter 0132.1 noted that the natural carbon cycle also takes a very 

long time to sequester CO2 from the atmosphere, resulting in current CO2 emissions that will not 

be sequestered in carbon sinks until sometime in the distant future. 

Commenter 0080.1 pointed out that when waste materials derived from fossil fuels (e.g., 

plastics) are land-filled, this carbon is once again sequestered and not released into the 

atmosphere as CO2 because fossil-fuel waste materials are essentially not degradable. This 

commenter also stated that when biomass is converted to a biofuel and combusted or converted 

directly to CO2 or methane by microorganisms (e.g., via waste composting or land-filling) any 

CO2 generated by these processes should be treated as no net increase to the atmosphere, and 

further stated that land-filling and composting of waste leads to increased sequestration of carbon 

that reduces atmospheric CO2.

Response:

2.6 Distinction Between Biogenic Carbon Dioxide that is Natural versus

Anthropogenic

 The distinction between biogenic and fossil CO2 reservoirs is an important 

consideration in accounting for biogenic emissions at stationary sources. Therefore, during the 

three-year deferral period, EPA will evaluate the distinctions between biogenic and fossil fuel 

CO2, and consider issues raised by commenters during the review. Regarding the legal basis for 

the deferral, please see Section 11 of this document or legal authority section of the preamble. 

Comment: Commenter 0059.1 supported deferral because, in their opinion, the Tailoring Rule 

makes no distinction between biogenic and anthropogenic CO2 emissions. Commenter 0059.1 
2.0 Carbon Cycle Dynamics Background and Conclusions

14

argued that only anthropogenic emissions should count towards the permitting thresholds for the 

following reasons:

• This approach is consistent with proposed federal and state regulations;

• Including biogenic emissions would dramatically increase the number of facilities subject 

to permitting. 

• A failure to distinguish between natural and anthropogenic emissions could potentially 

harm bioenergy expansion and would create the absurd result of regulating biogenic CO2

produced during destruction of anthropogenic methane from landfills.

Commenter 0059.1 stated that EPA rests its authority to regulate GHG on the endangerment 

finding of December 2009 and that the endangerment finding was silent on biogenic CO2, but 

stated that the U.S. Global Change Research Program (USGCRP) had confirmed evidence that 

GHG concentrations are now at elevated and unprecedented levels due to anthropogenic 

emissions.

In contrast, commenter 0083 encouraged EPA to consider that human activities related to forest 

products and forest product markets can also result in carbon sequestration. 

Response: Biogenic CO2 emissions can come from natural and anthropogenic sources. As 

stated in the proposed rule, natural processes such as fire and decomposition of unmanaged

lands, and human activities such as forest management and harvesting all release CO2 into the 

atmosphere. Therefore, during the three-year deferral period, EPA will conduct a detailed 

examination of the science associated with biogenic emissions, including the distinction between 

natural and anthropogenic fluxes, and EPA will consider these comments during the review 

process. 
3.0 PSD, Title V, and Tailoring Rule Background

15

3.0 PSD, Title V, and Tailoring Rule Background

EPA received a number of comments expressing views on requirements of and rationale for the 

Tailoring Rule, as well as on aspects of the PSD and Title V permitting programs that are beyond 

the scope of this rule.

3.1 Tailoring Rule Rationale and Requirements

Comment: Commenter 0074.1 stated that the proposed deferral rule is properly re-establishing 

EPA’s position in the major source Tailoring Rule proposal (that biogenic CO2 does not count 

toward regulatory thresholds), because the definition of “carbon dioxide equivalent, or CO2e” in 

the Tailoring Rule proposal invoked calculations used in the “Inventory of U.S. Greenhouse Gas 

Emissions and Sinks” (the Inventory), and these calculations do not count biogenic CO2

emissions at stationary sources. Rather, the Inventory states that it is assumed the carbon 

released during consumption of biomass is recycled as U.S. forests and crops regenerate which 

causes no net addition of CO2 to the atmosphere. Commenter 0074.1 also took exception to 

EPA’s statements in the deferral proposal that suggested stakeholders misunderstood EPA’s 

intent in the Tailoring Rule proposal and that references to the Inventory were not meant to 

indicate biogenic emissions would be excluded from applicability determinations. Commenter 

0074.1 countered that the proposed Tailoring Rule “specifically and repeatedly stated that EPA 

would use the Inventory not only for determining a pollutant’s global warming potential, but also 

‘for guidance on how to calculate a source’s GHG emissions’”(74 FR 55351, 55352, and 55361). 

Response:

Carbon dioxide equivalent, or CO2e, means a metric used to compare the emissions from 

various greenhouse gases based upon their global warming potential (GWP). The CO2e for a 

gas is determined by multiplying the mass of the gas by the associated GWP. The applicable 

GWPs 

 The reference to the Inventory of U.S. Greenhouse Gas Emissions and Sinks within 

the definition of carbon dioxide equivalent, or CO2e specified the procedure for converting 

individual masses of the six compounds that compose the New Source Review (NSR) regulated 

pollutant, GHG, into the metric used for major source threshold calculations and for significant 

increase calculations. The context of the usage within the Tailoring Rule proposal definition of 

CO2e indicated that the reference to the Inventory’s calculation methods was for conversions of 

non-CO2 GHG compounds to a CO2e basis (see 74 FR 55351):

and guidance on how to calculate a source’s GHG emissions in tpy CO2e can be found 

in

References to the Inventory’s guidance for conversion of non-CO2 GHG compounds to the 

standard GWP basis of the rule was not intended to be construed as references to the Inventory’s 

accounting conventions for biogenic CO2 emissions at stationary sources or in the LULUCF 

sector.

EPA’s ‘‘Inventory of U.S. Greenhouse Gas Emissions and Sinks,’’ which is updated 

annually under [an] existing commitment under the United Nations Framework Convention 

on Climate Change (UNFCCC). (Emphasis added.)

Comment: Commenters 0059.1 and 0080.1 supported deferral but did not agree with EPA’s 

claim at promulgation of the Tailoring Rule that there was insufficient time or information to 

apply “absurd results” and “administrative necessity” doctrines to biogenic CO2. Commenter 
3.0 PSD, Title V, and Tailoring Rule Background

16

0059.1 pointed out that the Tailoring Rule makes no distinction between biogenic and 

anthropogenic CO2 emissions unlike other international and federal policies where biogenic 

emissions are considered part of the natural carbon cycle and are not counted towards regulatory 

requirements. Commenter 0059.1 stated that unless EPA provides this distinction, sources 

whose CO2 emissions are largely biogenic, such as landfills and waste to energy (WTE) 

operations, would easily trigger regulatory thresholds established under the Tailoring Rule. 

Commenters (0071.1, 0072.1, 0120.1) also supported deferral and stated that EPA has the legal 

authority to distinguish biogenic CO2 from other GHG constituents and to exclude such 

emissions from Clean Air Act (CAA) programs, because biogenic CO2 has no adverse impacts

on human health or the environment, and EPA has historically excluded certain air emissions 

from CAA programs even when such emissions are otherwise regulated in some contexts;

commenter 0071.1 also stated that it would be administratively impossible to regulate biomass, 

and both commenters (0071.1 and 0072.1) stated that EPA can use discretion to avoid imposing 

burdens on permit applicants and permit authorities. Commenters (0023E, 0023G, 0106.1, and 

0143.1) opposed the deferral and noted that the Tailoring Rule clearly states that all CO2 counts 

towards determining whether a stationary source is major, and therefore sources must hold 

construction and Title V operating permits for GHG emissions that reflect BACT.

Response: The record compiled to support the Tailoring Rule was based on permitting burdens 

estimated using the traditional 100/250 tons per year (tpy) major source permitting threshold for 

non-GHG applied to GHG. As explained in the preamble to the Tailoring Rule, EPA did not at 

the time the Tailoring Rule was finalized consider the associated rationale for tailoring new GHG 

thresholds for permitting applicability purposes a sufficient basis to exempt certain emissions 

from the PSD and Title V programs. However, in the final Tailoring Rule preamble, we stated 

that the decision not to provide a biogenic exclusion did not foreclose EPA’s ability to either (1) 

provide this type of an exclusion at a later time when we have additional information about 

overwhelming permitting burdens due to biomass sources, or (2) provide another type of 

exclusion or other treatment based on some other rationale. In the final Tailoring Rule preamble 

we also recognized the merit in commenters’ observations about accounting for various biomass 

feedstocks, and we stated our intention to seek further comment on how we might address 

emissions of biogenic CO2 under the PSD and Title V programs through a future action. In order 

to properly exercise discretionary authority consistent with the Act, we believe that a detailed 

examination of the science and technical issues associated with accounting for the net 

atmospheric impacts of biogenic CO2 emissions will address the issues raised by the commenter 

in future rulemaking we conduct to provide for such an accounting in the permitting programs.

Comment: Commenter 0079.1 disagreed with the underlying premise necessitating the 

proposed deferral, that GHG are able to trigger PSD in the first place even though there is no 

National Ambient Air Quality Standard (NAAQS) for GHG. The commenter stated that GHG

were not intended to be regulated under the PSD program. The commenter cited its comments 

(attached to their current comments) filed on the PSD and Title V Tailoring Rule proposal in 

support of the commenter’s contention that Part C of Title I did not contemplate non-criteria 

pollutants triggering PSD. The commenter also disputed EPA’s statements on page 15257 of the 

proposed deferral Federal Register (FR) notice stating that the scope of applicability of the PSD 

program is driven solely by the definition of “major emitting facility” in CAA Section 169 and 

the definition of “major stationary source” in 40 CFR § 51.166. 
3.0 PSD, Title V, and Tailoring Rule Background

17

Response: The commenter’s interpretation of Part C of Title I is inconsistent with the 

longstanding definition of “regulated NSR pollutant” under 40 CFR Parts 51 and 52, because this 

definition (which predates the Tailoring Rule amendments) only includes existence of a NAAQS 

as one of four types of pollutants that are subject to NSR regulation; the remaining three types of 

pollutants defined as NSR pollutants have bases independent of NAAQS. Furthermore, the fifth 

paragraph under the definition of “regulated NSR pollutant” (e.g., 40 CFR 51.166(b)(49)(v)) 

exemplifies why formal regulatory text is required to constrain unintended PSD applicability 

relative to rulemakings under CAA authorizations other than Part C of Title I (such as motor 

vehicle standards under Title II). Finally, the commenter’s interpretations are also inconsistent 

with the Administrator’s obligations and congressional purposes under Section 202(a) and 

Section 160(1) of the Act, respectively. EPA believes that the cited “major” definitions are 

integral to achieving the purposes of Part C of Title I based on the Supreme Court’s holding that 

GHG are air pollutants under the Act; the purpose and authority under Section 160(1) for the 

Administrator to protect public welfare from reasonably anticipated endangerment posed by air 

pollutants; the 2009 Endangerment Finding; and the pre-construction permitting requirements for 

major sources of air pollutants under Section 165(a) of the Act.

Comment:

Conversely, commenter 0042.1 stated that deferral is required so EPA can keep the commitment 

to reconsider treatment of biogenic emissions under CAA permitting programs consistent with 

the Tailoring Rule. Additionally, commenter 0043.1 would like to work with EPA to determine 

how to model the impact of carbon-based fuel sources and biogenic stationary sources. The 

commenter expressed concern regarding how these sources may be regulated if EPA does not 

amend the rules. Both commenters 0042.1 and 0043.1 urged EPA to consider employing a 

standard similar to the “enforceable commitment” for biogenic energy sources that is similar to 

the language included in the Tailoring Rule. Commenter 0043.1 noted that this would create a 

framework for regulation with specific targets set for categories of stationary fuel sources and 

would provide the flexibility necessary to adapt to the changing technology that makes use of 

biogenic energy viable. Another commenter (0139.1) was concerned about implications in the 

proposal that EPA would favor certain forms of biomass over other forms and concerns that EPA

may intend to develop land use regulations under PSD; the commenter pointed out that federal 

regulation of state and private land use is an enduring controversial issue that has been left to the 

states.

 Commenter 0132.1 opposed deferral and stated that EPA has no authority to avoid 

federal regulations of greenhouse gas emissions and stated that references to the IPCC 

methodology for reporting biogenic emissions could not be used as a legitimate basis for the 

Agency to avoid responsibilities mandated by Congress in the Act.

Response:

3.2 Tailoring Rule Applicability Thresholds

 EPA notes that the cited references to the IPCC convention for reporting biogenic 

emissions from the LULUCF sector occur within the proposal’s “Relevant Background” section 

as well as relevant background to our commitment to re-evaluate biogenic emissions in major 

source permitting. 

Comment: One commenter (0023B) stated that the major source threshold for PSD should be 

increased to 200,000 tons of CO2 per year if the intent is to truly regulate the largest emitters and 
3.0 PSD, Title V, and Tailoring Rule Background

18

stated that operators of facilities previously not classified as major sources continue to have 

concerns about being regulated under EPA’s Tailoring Rule, a regime designed for only “the 

very largest commercial facilities.”

Response:

3.3 March, 2011 Updated Permitting Guidance

 The deferral does not include revisions to the major source thresholds for GHG. 

This rule is solely focused on biogenic CO2 emissions from stationary sources subject to the PSD 

and Title V programs. The GHG applicability thresholds are discussed in the Tailoring Rule and 

in the response to comments (RTC) document associated with the Tailoring Rule. Revisions to 

the major source thresholds are outside the scope of this rulemaking. 

Comment:

For instance:

Commenter 0056.1 stated that there is risk going forward that permitting actions at 

industrial sources, such as refineries, will be required to address, and possibly in some cases 

adopt, the use of biomass fuel to meet a state’s BACT determination, because of “redefining the 

source” language in the newly-released BACT guidance that contains language implying that 

states have the latitude to consider this form of BACT in future permit actions, even to the extent 

of “redefining the source”. The commenter contended that this interpretation is extremely 

problematic and violates one of the primary tenants of the PSD program to only consider control 

options for the project under consideration, and not require a fundamental redesign of a project. 

EPA states: “The ‘redefining the source’ issue is ultimately a question of degree that is 

within the discretion of the permitting authority.” (pg. 13)

“EPA has recognized that a Step 1 (of the top-down BACT process) list of options need not 

necessarily include inherently lower polluting processes that would fundamentally redefine 

the nature of the source proposed by the permit applicant” (pg. 12).

“If the permit applicant is unable to demonstrate that a different allocation of primary fuels 

would fundamentally redefine the proposed source, the options at Step 1 should include 

varying allocations of the two primary fuels if the proportional allocation of fuels has the 

potential to affect the amount of GHG emitted from the facility or the net atmospheric GHG 

concentrations.” (pg. 16).

These excerpts from the March 2011 guidance document all clearly indicate that:

1. “Redefining the source” is simply one “tool” of many that permitting authorities may use 

in NSR permit actions,

2. This “tool” of “redefining the source” should be considered in NSR permit actions, and

3. Permit applicants must consider “alternative processes” in their top-down BACT 

evaluation.

The commenter stated that any requirement to “redefine the source” in an NSR permitting action 

is contrary to the statutory and regulatory language and intent of the NSR permitting regulations. 

Furthermore, this guidance document is another example of “regulations through guidance” in 

which the regulated communities (and permitting authorities) are being required to comply with 
3.0 PSD, Title V, and Tailoring Rule Background

19

Agency actions that have not undergone the proper rulemaking process of publication and public 

vetting.

The commenter objected to this language in the GHG BACT guidance documents and requested

that any reference or inference to “redefining the source” be removed.

Response: To clarify, EPA issued the interim guidance entitled, “Guidance for Determining 

Best Available Control Technology for Reducing Carbon Dioxide Emissions from Bioenergy 

Production” to help permitting authorities establish a basis for concluding that under PSD 

Programs the combustion of biomass fuels can be considered BACT for biogenic CO2 emissions 

at stationary sources before the deferral becomes effective. The interim BACT guidance is 

unnecessary and inapplicable in those jurisdictions where the deferral becomes effective while 

EPA conducts the scientific review of biogenic CO2 emissions and develops the accounting 

framework outlined in the preamble to this action. During this period, EPA will conduct a 

detailed examination of the science associated with biogenic CO2 emissions from stationary 

sources, including engaging with federal partners, technical experts, and an independent 

scientific panel to consider technical issues. Based on the feedback from the scientific and 

technical review, EPA will then undertake a rulemaking to determine how biogenic CO2

emissions should be treated and accounted for in PSD and Title V permitting. The proposed 

deferral focuses on biogenic CO2 emissions from stationary sources subject to the PSD and 

Title V programs. EPA considers comments on the interim BACT guidance to be beyond the 

scope of this action.
4.0 Recent Actions/Procedures

20

4.0 Recent Actions/Procedures

4.1 National Alliance of Forest Owners (NAFO) Petition

Comment: Commenter 0023A stated that deferral and further scientific study are appropriate 

steps in response to NAFO’s petition, because EPA did not properly inform stake holders on the 

treatment of biogenic CO2 in the Tailoring Rule proposal. Similarly, commenter (0087.1) 

believes EPA was justified in granting the petition for reconsideration, because the final 

Tailoring Rule presented new issues and commenters never had an opportunity to address EPA’s 

justification for including biogenic CO2.

Response: We agree with these commenters that the deferral is an appropriate step in light of 

the unique complexity posed by biogenic CO2 emissions. However, we also respectfully note 

that commenters did, in fact, have the opportunity to comment on the treatment of biogenic 

emissions during the Tailoring Rule process, and EPA received a number of comments in this 

regard. These comments were addressed in the final Tailoring Rule, where EPA also noted that 

the Agency had not yet evaluated the permitting burdens associated with biogenic CO2

emissions, and had not received comments indicating that an overwhelming burden justified 

exclusion at that time (75 FR 31,514, 31,591). There, we also indicated our intent to solicit 

additional comments, and perform the further investigation necessary to determine how to best 

treat biogenic CO2 emissions. Id. The present action fulfills that intent, and enables the Agency

to make its final decision on the treatment of these emissions based on a thorough analysis of 

applicable science and policy concerns.

Comment: Commenter 0023E stated that EPA’s decision to grant the Tailoring Rule 

reconsideration request brought by NAFO is unlawful, because industry sought biogenic 

exemption during the Tailoring Rule comment period, and NAFO’s request to reconsider the 

Tailoring Rule does not meet the requirements CAA Section 307(d)(7)(B).

Response:

Courts have consistently held that administrative agencies have inherent authority to reconsider 

their decisions. In Chevron v. NRDC, the Supreme Court noted that “[a]n initial agency 

interpretation is not instantly carved in stone,” rather, the agency “must consider varying 

interpretations and the wisdom of its policy on a continuing basis.” 467 U.S. 863-864 (1984). 

Lastly, this interpretation of Section 307(d)(7)(B), as it relates to EPA’s inherent authority to 

reconsider a rule, is consistent with past EPA practice. For example, on May 14, 2009, EPA 

issued a final rule announcing its decision to extend the effective date of its rule regarding 

‘‘aggregation’’ under the PSD and NSR programs. 74 FR 22,693, 22,693. 

 We disagree with this commenter’s analysis of the statute or the legal justification 

for granting reconsideration on this issue. It is EPA’s view that rather than circumscribing the 

Agency’s authority to reconsider a rule, Section 307(d)(7)(B) serves to define a situation where 

EPA must reconsider a rule. Id. This does not prohibit or otherwise limit EPA’s authority to 

reconsider a rule under circumstances outside of those defined in the statute. In Section

307(d)(7)(B) Congress set out when EPA must reconsider a rule; nowhere did Congress state that 

EPA may not consider a rule or change a past decision in other circumstances. 
4.0 Recent Actions/Procedures

21

Comment: Commenter 0014.1 noted that the petition for reconsideration was filed by an entity 

on the sequestration side of the biogenic balance due to speculative fears of economic 

impairment to regulated trading partners, and stated that EPA should consider that the petitioner 

may not be “directly affected by the ruling,” because permit applications are case-by-case 

examinations of sources. Commenter 0014.1 stated that if the petitioner does have members that 

operate sources, these members must operate under emissions constraints without consideration 

of other members’ sequestration areas because the presumption that equivalent sequestration is 

occurring off-site is theoretical without a case-by-case analysis.

Response: In general, comments on the economics of the biomass industry are beyond the scope 

of this action. EPA notes that there is no statutory or regulatory requirement that specifies how, 

or to what degree, a petitioner must be directly affected by the outcome of an agency’s decision 

to grant or deny a Petition for Reconsideration. Specifically addressing the commenter’s concern 

that NAFO’s interest was only speculative, EPA notes that forest owners often have on-site 

biomass-fueled electric generating units (EGUs) to power their operations; these units are subject 

to EPA’s determination regarding the regulation of CO2 emissions from biogenic sources. 

Comment:

The commenter also noted that EPA had not satisfied the statute’s procedural requirements 

governing decisions on submitted Petitions for Reconsideration, in that Administrator Jackson 

published her final decision to reconsider the rule in the proposed deferral notice. The 

commenter stated EPA provided no opportunity for public comment either on the industry 

group’s Petition for Reconsideration (which was never even docketed in the Tailoring Rule 

record, or relied on by the industry group in its filings in the litigation over the Rule), or on 

EPA’s sua sponte decision to reconsider this aspect of the Tailoring Rule. 42 U.S.C. §§ 7607 

(d)(1)(J) (notice and comment requirements apply to the “promulgation or revision of”

regulations under part C of subchapter I [the PSD provisions]”(emphasis added)); 7607(d)(2)(B) 

(the Administrator “shall convene a proceeding for reconsideration of the rule and provide the 

same procedural rights as would have been afforded had the information been available at the 

time the rule was proposed”). The commenter stated the nature of EPA’s decision-making 

process here is not only unlawful in its own right, but further demonstrates the unreasonable, 

arbitrary and capricious nature of this highly political decision-making.

 Commenter 0350.1 stated that EPA’s final decision to reconsider the Tailoring Rule 

does not meet the strict requirements of CAA §307(d)(2)B) for such decision making. The 

commenter stated EPA is only required to reconsider a rule based on a Petition for 

Reconsideration if the petitioner demonstrates to EPA that (1) it was impracticable to raise the 

objection during the comment period, or (2) that the grounds for such objection arose after the 

comment period but within the time specified for judicial review. The commenter stated that the 

industry group submitted extensive comments to the Tailoring Rule docket on the very issues it 

now raises in its Petition. The commenter stated the industry group’s petition does not satisfy 

either the statute’s strict limitations on reconsideration, or EPA’s recent interpretation of them. 

The commenter cited a recent EPA statement that says “section 307(d)(7)(B) does not provide a 

forum to request EPA to reconsider issues that actually were raised, or could have been raised, 

prior to promulgation of the final rule.”

Response: Several commenters expressed their view that EPA’s discretion to reconsider its 

treatment of CO2 emissions from biogenic sources is limited by Section 307(d)(7)(B) of the 
4.0 Recent Actions/Procedures

22

CAA. We disagree with these commenters’ analysis of the statute. It is EPA’s view that rather 

than circumscribing the Agency’s authority to reconsider a rule, Section 307(d)(7)(B) serves to 

define a situation where EPA must reconsider a rule. Id. This does not prohibit or otherwise 

limit EPA’s authority to reconsider a rule under circumstances outside of those defined in the 

statute. One commenter (0351.1) states that “EPA is only required to reconsider a rule based on 

a Petition for Reconsideration” if the petition makes the requisite showings per 307(d)(7)(B). 

This phrasing reiterates the plain language of this section. In Section 307(d)(7)(B) Congress set 

out when EPA must reconsider a rule; nowhere did Congress state that EPA may not consider a 

rule or change a past decision in other circumstances. 

Courts have consistently held that administrative agencies have inherent authority to reconsider 

their decisions. In Chevron v. NRDC, the Supreme Court noted that “[a]n initial agency 

interpretation is not instantly carved in stone,” rather, the agency “must consider varying 

interpretations and the wisdom of its policy on a continuing basis.” 467 U.S. 863-864 (1984). 

Lastly, this interpretation of Section 307(d)(7)(B), as it relates to EPA’s inherent authority to 

reconsider a rule, is consistent with past EPA practice. On May 14, 2009, EPA issued a final 

rule announcing its decision to extend the effective date of its rule regarding ‘‘aggregation’’ 

under the PSD and NSR programs. 74 FR 22,693, 22,693. In response to a petition for 

reconsideration issued by the Natural Resources Defense Council, EPA proposed this deferral to 

give the Agency sufficient time to reconsider the rule, as a three-month administrative stay 

issued pursuant to 307(d)(7)(B) was inadequate. Id. Section 307(d)(7)(B) does not diminish 

EPA’s inherent authority — via a new rulemaking such as the one undertaken here — to revise 

and reconsider its past rules and policies. 

One commenter also expressed concern that EPA’s decision to grant the Petition for 

Reconsideration was not opened up to public comment. EPA is not required to elicit public 

comment before deciding whether to grant or deny a Petition for Reconsideration. However, 

after EPA decided to grant the Petition for Reconsideration in its corresponding decision to 

reconsider the treatment of CO2 from biogenic sources, EPA solicited public comments and held 

a public hearing. EPA complied with all procedural requirements in issuing the proposed rule.
5.0 Consistency Among Programs

23

5.0 Consistency Among Programs

Comment:

Commenter 0070.1 stated that electric utilities that are subject to renewable energy standard

(RES) requirements in 29 states and the District of Columbia rely upon biomass, to varying 

degrees, to meet their compliance obligations. Biomass is part of the full portfolio of 

technologies and measures that electric utilities need to reduce GHG emissions, while continuing 

to provide reliable and affordable electric power in a manner that is consistent with a host of 

federal and state regulations. Permanent exemption of biogenic CO2e emissions from bioenergy 

and other biogenic stationary sources from PSD and Title V permitting further promotes 

compliance with voluntary or mandatory related RES policies.

Several commenters (0015.1, 0052.1, 0053.1, 0059.1, 0062.1, 0063.1, 0070.1, 

0074.1, 0080.1, 0082.1, 0086.1, 0099.1, 0108.1, and 0126.1) highlighted acknowledgement of 

carbon neutrality of biogenic fuels in international, U.S. government (including EPA) and State

regulatory and policy programs. Commenter 0053.1 noted that biogas is considered an important 

alternative energy source in Europe. Commenters 0062.1 and 0080.1 stated that EPA and other 

federal agencies, states and international groups have recognized the carbon neutrality of 

biogenic carbon in municipal solid waste (MSW) and landfills. The commenters provided 

multiple examples of regulatory and policy programs that treat biogenic fuels as a carbon neutral. 

One commenter (0059.1) listed a variety of international and domestic protocols and accounting 

systems that exclude biogenic CO2 emissions including: EPA’s GHG inventory, Clean 

Development Mechanism of the Kyoto Protocol, applicability determination for the EPA’s GHG 

Reporting Program, H.R. 2454, and California’s AB32 program. In addition, biomass emissions 

from combustion or non-combustion sources have not been capped under the current draft of the 

California cap-and-trade system, the Kyoto Protocol, the European Union Emission Trading 

Scheme (EU-ETS), or the Regional Greenhouse Gas Initiative (RGGI).

Response: The accounting approaches taken by other programs, including other EPA programs, 

will be included in EPA’s detailed examination of the scientific and technical issues related to 

biogenic CO2 emissions and any subsequent rulemakings we undertake during the deferral 

period.

Comment: Commenter 0108.1 stated that disqualifying bio-power as a form of renewable 

energy puts the U.S. at a grave disadvantage in the international arena. Treating biogenic carbon 

emissions from bio-power the same as fossil fuels sets a poor precedent for biofuels and may 

raise unneeded controversy around the existing Renewable Fuel Standard (RFS).

Response: The deferral rule relates to the applicability of biogenic CO2 emissions within the 

context of the PSD and Title V programs, and does not establish precedent for accounting for 

biogenic CO2 emissions associated with any RFS programs. Those programs are outside the 

scope of this rulemaking.

Comment: Commenter 0111.1 stated that deviations from sustainable forestry are already 

accounted for by the Land Use, Land-Use Change and Forest (LULUCF) protocol from the 

UNFCCC. The commenter encourages the EPA during its rulemaking to not duplicate this 

accounting process nor risk double counting emissions from the energy sector.
5.0 Consistency Among Programs

24

Response:

Any application of an accounting methodology to a particular stationary source program will be 

addressed through a future rulemaking and not this rulemaking. EPA will evaluate accounting 

methodologies during the three-year deferral period.

 As explained in the preamble, the Inventory addresses biogenic CO2 emissions in the 

LULUCF chapter to avoid double counting of those emissions in the Energy chapter at the 

national level. As also explained in the proposal, the Inventory was not designed to quantify the 

net atmospheric impacts of a particular type of fuel from a stationary source over a specified time 

period that extends into the future. 
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

25

6.0 Biomass-Related Definitions and Affected Industries in the 

Deferral Rule

Comment: Commenter 0086.1 stated that EPA should make clear that it will not be reassessing 

the concept of carbon neutrality of biofuels under Title II of the CAA during the detailed 

scientific review referenced in the proposal, and further stated that any actions considered by 

EPA should remain separate from EPA actions with respect to regulation of fuels under Title II 

of the CAA, because EPA’s lifecycle analysis under the RFS found that mobile source emissions 

should only include non‐CO2 gases, because the carbon emitted from biogenic fuel combustion is 

offset by the uptake of biogenic carbon during feedstock production. The commenter also noted 

that biofuels produced for mobile sources are also used in stationary sources.

Response:

6.1 Affected Industries

The final rule, which defers inclusion of biogenic CO2 from major stationary source 

applicability determinations under PSD and Title V, does not alter any regulatory text related to 

mobile sources or Title II of the CAA. This rulemaking does not address the treatment of 

biogenic CO2 emissions from mobile sources and within the RFS Program. Those programs and 

regulations are outside the scope of this rulemaking. 

Comment: Commenter 0054.1 stated that sugar industry processors operate industrial boilers 

fired primarily by bagasse, which is a co-product of sugarcane processing. Bagasse is a 

renewable, carbon-neutral fuel. The sugar industry uses bagasse to reduce its demand for fossil 

fuel and other sources of energy. Sugarcane processors operate boilers at sugar mills to produce 

process steam. The bagasse boilers burn 100-percent bagasse most of the time. A small amount 

of fossil fuel is burned at times, primarily for startup. The commenter operates a seasonal 

industry, with operations running October through April or May of each year, with one mill 

operating year-round to support sugar refining operations. Because the commenter’s facilities 

combust almost exclusively bagasse, their facilities emit significant amounts of CO2. However, 

over 98 percent of these CO2 emissions are biogenic in nature.

Response: EPA recognized in the preamble of the proposal that the potential may exist for it to 

determine in subsequent rulemaking that multiple types of biomass feedstocks would have a 

negligible or de minimis impact on the net carbon cycle, and that CO2 emissions from such 

feedstocks would result in a negligible net atmospheric impact. In particular, EPA noted that this 

may apply to residue or byproduct material that if not used as a bioenergy feedstock would have 

decomposed under natural circumstances in a relatively short period of time. The three-year

deferral will allow time for a detailed and transparent examination of the science associated with 

the net atmospheric impact of biogenic CO2 emissions, including CO2 emissions from 

agricultural byproducts and to conduct the subsequent rulemaking. 

Comment: Commenter 0084.1 recognized that agribusiness organizations are engaged in 

manufacturing and other operations that generate or have the potential to generate biogenic CO2

emissions, and as a result are subject to permitting under the CAA. The commenter stated that 

such permitting hinders the ability of agribusinesses to respond nimbly and flexibly to changing 

market conditions.
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

26

Response: EPA acknowledges the comment and notes that the final rule defers for three years 

the application of PSD and Title V permitting requirements to biogenic CO2 emissions. 

Comment: Commenter 0086.1 referred to EPA’s 2007 FR notice that clarified ethanol facilities 

are not “chemical process plants” subject to the 100 tpy major source threshold under PSD, and 

stated that the Tailoring Rule and uncertainty of outcomes following the deferral proposal have 

undermined EPA’s 2007 decision about ethanol plants. This commenter goes on to quote 2007 

FR passages about ethanol’s role in balancing energy independence, environmental protection, 

and economic growth.

Response: We disagree that the Final Tailoring Rule and deferral of applicability for biogenic 

CO2 emissions in PSD and Title V permitting undermines our 2007 decision. The 2007 decision 

applies to applicability thresholds for criteria air pollutants (not GHG).

Comment:

Commenter 0129.1 asserted that without deferral, biogenic CO2 emissions will trigger PSD at 

many landfills from the combustion of landfill gas in flares and landfill gas renewable energy 

projects, which have resulted in significant GHG reductions in recent years. The commenter 

stressed that even without the Tailoring Rule, permitting is complex for solid waste landfills 

because of PSD and New Source Performance Standards (NSPS) requirements. The commenter 

further expressed that deferral and exemption of biogenic CO2 from landfill flaring and landfill 

gas renewable energy projects would make the Tailoring Rule more consistent with NSPS 

requirements for gas collection and combustion that already reduce the GWP of landfill GHG 

emissions.

Commenter 0145.1 stated that the wide range of definitions for “biomass” in state 

and federal laws, including the “inadequate” definition in the deferral proposal, allow industry to 

evade regulation by confusing permitting authorities with the definition of “biomass” and state 

incentives for renewable energy. The commenter provided some specific examples of air permits 

to burn solid waste that have been issued to biomass projects and stated that one project was able 

to avoid solid waste incinerator facility siting laws by calling itself a renewable energy biomass 

project. 

Response: EPA recognizes the complex relationships between state and federal solid waste and 

air pollution laws and the challenges that permitting authorities and solid waste managers face 

integrating the disparate requirements and definitions of these programs into enforceable permit 

conditions. EPA also recognizes that Section 111 standards and guidelines should complement 

PSD program objectives but such considerations are not related to this rulemaking. The 

commenter’s allegations that a solid waste incinerator avoided applicable siting laws are outside 

the scope of the biogenic CO2 emissions deferral rulemaking and it is suggested that the 

commenter voice these types of project-specific concerns with compliance personnel at the 

appropriate state environmental agency or EPA regional office.

Comment: Commenter 0116.1 noted that the preamble in the deferral proposal refers several 

times to EPA’s intention to exclude “fossil fuel” from the deferral. However, the EPA sweeps 

too broadly by including CO2 emissions from the anthropogenic (or non-biogenic) portion of the 

MSW processed at WTE facilities. The commenter pointed out that local governments utilize

WTE because it is the best means for managing non-recycled waste and indicated that such 
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

27

utilization did not constitute “a fuel choice.” The commenter also stated that subjecting the nonbiogenic portion of WTE CO2 emissions to PSD and Title V permitting requirements would 

discourage WTE projects.

Response: EPA notes the commenter’s claims that the operation of WTE facilities result in 

reductions in GHG emissions, which provide the basis for advocating that the CO2 emissions 

from the fossilized portion of the MSW feedstock also be deferred, are related to the biogenic 

portion of the MSW feedstock, not the fossilized portion. The final rule defers for three years 

the application of PSD and Title V permitting requirements to biogenic CO2 emissions. EPA 

recognized in the preamble of the proposal that the potential may exist for it to determine in 

subsequent rulemaking that multiple types of biomass feedstocks would have a negligible impact 

on the net carbon cycle, and that CO2 emissions from such feedstocks would result in a 

negligible net atmospheric impact. The three-year deferral will allow time for a detailed 

examination of the science associated with the net atmospheric impact of biogenic CO2

emissions, including those CO2 emissions from WTE facilities, and to conduct the subsequent 

rulemaking. EPA recognizes that policies and permitting decisions related to GHG emissions 

from WTE facilities must consider factors unique to the MSW feedstock, and EPA notes that the 

current knowledge of GHG emissions from landfills and WTE facilities allow operators to 

evaluate the climate impacts of each of these disposal options. 

Comment: Commenter 0056.1 stated that “biogenic activities” should encompass everything 

from fermentation processes to the combustion of renewable fuels, including ethanol 

manufacturing, biodiesel production, and other alternative energy production based on biomass 

feedstocks.

Response: EPA agrees that the activities described by the commenter represent activities that 

result in biogenic CO2 emissions, as provided in the definition of “biogenic CO2 emissions” in 

the preamble of the proposal. This definition includes CO2 from combustion or decomposition of 

biologically-based materials, including CO2 from fermentation during ethanol production and 

CO2 derived from combustion of biological material, including all types of wood and wood 

waste, forest residue, and agricultural material.

Comment: Commenter 0107.1 requests that EPA recognize the natural rubber content of tires 

and exempt the CO2 emissions from the biogenic fraction of tire-derived fuel (TDF) from GHG 

reporting requirements. The commenter’s U.S. tire shipment data for 2008 indicates that the 

overall percentage of TDF that is natural rubber or biomass is approximately 26 percent. The 

commenter stated that TDF reduces net carbon emissions because it contains natural rubber,

which is biomass that is produced by sequestration of carbon dioxide through photosynthesis in

rubber trees.

Response: EPA agrees that the natural rubber content of tires represents non-fossilized and 

biodegradable organic material, and that CO2 emissions resulting from the combustion or 

decomposition of such material is included in the three-year deferral of the application of PSD 

and Title V permitting requirements to biogenic CO2 emissions. The three-year deferral will 

allow time for a detailed and transparent examination of the science associated with the net 

atmospheric impact of biogenic CO2 emissions, including CO2 emissions from the biological 

fraction of TDF.
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

28

Comment: Commenter 0125.1 reviewed their industry’s use of wood pulping co-products, 

where they extract all useful chemical components and then recover fuel value from residual byproducts. The commenter noted that EPA’s use of the term “biogenic” in the proposed rule 

appears to establish greater value for biomass used for bioenergy than for bio-based products. 

The commenter expressed concern that “wood waste and forest residue” is not well defined and 

the impact of the deferral on the commenter’s industry is not clear. Without clarification, the 

rule could damage availability of the commenter’s feedstocks.

Response: EPA’s use of the term “biogenic” is neutral with regard to the economic use of the 

biogenic material. The term “biogenic” is used to refer to CO2 emissions resulting from the 

combustion or decomposition of biologically-based materials other than fossil fuels. With regard 

to the definition of wood waste and forest residue, EPA does not believe that the broad 

regulatory language used in the final deferral rule has the potential to omit certain wood waste 

and forest residue categories, as it includes CO2 emissions resulting from the combustion or 

decomposition of all forest products, by-products, residues and waste. The regulatory language 

of the final deferral rule includes “products, by-products, residues and waste from agriculture, 

forestry and related industries...”

Comment: Commenter 0354.1 stated that in the preamble to the proposal, EPA specifically 

cites fermentation processes as an affected entity, with the examples of ethanol manufacturing 

and food/beverage processors using fermentation processes. However, there are other 

fermentation processes, namely in the pharmaceutical and biotechnology business, that also emit 

CO2 as a result of micro-organism transformation. EPA should clarify in the final rule preamble 

that all industrial fermentation processes would be covered under the deferral. EPA should also 

clarify that CO2 emissions resulting from the thermal decomposition of volatile organic 

compounds (VOCs) that are released when processing biomass are considered biogenic CO2

emissions and are therefore covered under the deferral. Furthermore, the commenter noted the 

proposed language in §§51.166, 52.21, and 70.2 states that the deferral applies to “...carbon 

dioxide emissions resulting from the combustion or decomposition of non-fossilized and 

biodegradable organic material originating from plants, animals, or micro-organisms...”

However, this definition does not appear to include the consumption of organic material by 

micro-organisms, which is what occurs during industrial fermentation processes.

Response: EPA agrees that other fermentation processes in addition to ethanol fermentation 

also result in CO2 emissions and are covered under the deferral provided in the final rule. While 

the examples of affected entities provided in Table 1 of the preamble to the proposal are 

illustrative and not intended to be exhaustive, in developing the preamble to the final rule, EPA 

has included in Table 1 the industrial classification category of “medicinal and botanical 

manufacturing” (NAICS 325411) in response to the comment. In response to the comment, EPA 

has also included in the preamble to the final rule a clarification that all forms of industrial 

fermentation represent an example of biogenic CO2 emissions, by clarifying the fermentation 

example to state “CO2 from fermentation during ethanol production or other industrial 

fermentation processes” (emphasis added). With respect to the comment regarding CO2

emissions resulting from the thermal decomposition of VOC that are released when processing 

biomass, EPA believes that such emissions are addressed in the phrase “decomposition of nonfossilized and biodegradable organic material” at §§51.166, 52.21, 70.2, and 71.2 of the final 

rule. With respect to the comment regarding language in §§51.166, 52.21, 70.2, and 71.2 of the 
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

29

final rule stating that the deferral applies to “...carbon dioxide emissions resulting from the 

combustion or decomposition of non-fossilized and biodegradable organic material originating 

from plants, animals, or micro-organisms...”, EPA believes that this language applies to the 

scenario described by the commenter involving the production of CO2 by micro-organisms 

during industrial fermentation processes. In such processes, biological materials are used as a 

growth media for microbes. In such a case, CO2 emissions result from the decomposition of 

biodegradable organic material and originate from micro-organisms. 

6.2 Meaning of “Biologically-Based Material”

Comment: Commenters 0051.1 and 0077.1 encouraged use of a broad definition of “biologicalbased material” and one that is flexible, so that it does not limit future technologies and biomass 

feedstocks. Commenter 0077.1 supports the broadest definition possible, given the diversity of 

biological material that could be used, and listed the following types of biologically-based 

materials used as energy sources in meat plant operations: rendered fats and recycled restaurant 

grease, tallow, sunflower hulls, biogas from wastewater treatment, biogas from manure 

treatment, and landfill gas.

Response:

6.3 Meaning of Preamble Terms “Bioenergy and Other Biogenic Sources”

or “Biogenic CO2 Emissions”

 “Biologically-based material” is included as a specific definition in the final rule (as 

proposed without change). EPA agrees that the materials noted by the commenter (rendered fats 

and recycled restaurant grease, tallow, sunflower hulls, biogas from wastewater treatment, biogas 

from manure treatment, and landfill gas) are within the scope of the description of biologicallybased material in the final rule (as proposed without change), which includes: “non-fossilized 

and biodegradable organic material originating from plants, animals, or micro-organisms 

(including products, by-products, residues and waste from agriculture, forestry and related 

industries as well as the non-fossilized and biodegradable organic fractions of industrial and 

municipal wastes, including gases and liquids recovered from the decomposition of nonfossilized and biodegradable organic material).” 

Comment:

1) Materials eligible for immediate, permanent exemption include materials for which the 

carbon content would likely return to the atmosphere in the near-term if the material is not 

used to produce energy: 

Commenters 0023J and 0070.1 supported EPA’s definition of biogenic CO2

emissions in the proposal and agreed with the list of biogenic CO2 emissions in the proposed 

rule. Commenter 0086.1 requested that EPA clarify in the final rule that CO2 emissions from the 

combustion of liquid biofuels, such as ethanol and biodiesel, in stationary power units should 

also be excluded. Commenter 0075.1 recommended that EPA separate feedstocks into two 

groups based on current knowledge of biomass-to-energy cycles. One group should be granted 

immediate permanent exemption from PSD and Title V permitting requirements, while the 

second group would be subject to further study as proposed by EPA. The two groups were 

described as follows:

a) Forest and agricultural wastes;

b) Urban wood wastes;
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

30

c) Removals associated with ecosystem restorations and maintenance of right-of-ways; and

d) Crops on lands in continuous agricultural production for a number of years. 

2) Materials subject to the deferral as proposed include materials where CO2 emission 

reduction benefits are open to questions and where further study is appropriate, such as:

a) Vegetable oils where indirect land-use change emissions can be substantial;

b) Materials from land recently converted from forest or grassland to tillage crops; 

c) Chipped or pelletized materials from whole trees; and 

d) Materials shipped long distances between harvest and the point of use. 

Commenter 0087.1 urged EPA to affirm the findings in the proposal that some feedstocks have a 

“negligible impact on the net carbon cycle” when utilized to produce energy or “would clearly 

reduce net atmospheric CO2 levels.” The commenter asked EPA to expand the list of such 

feedstocks referenced in the proposal to include forest residues and spent pulping liquor and 

provided key points of several research studies, as well as a lifecycle analysis, to support this 

request. The commenter concluded that the lifecycle analysis demonstrates the GHG and 

renewable energy benefits of combusting spent pulping liquors for energy.

Response:

6.4 Open-Loop Biomass

 EPA believes that the definition in the final rule provides permitting authorities 

sufficient flexibility to identify biogenic feedstocks during the deferral period, and EPA agrees 

that the biogenic fraction of liquid biofuels combusted by stationary sources is within the scope 

of the proposed definition. Regarding differentiation of feedstocks and suggestions to apply the 

deferral to only a subset of biogenic feedstocks, EPA believes that this type of differentiation 

requires a scientific record of analyses and peer review. EPA plans to complete these analyses in 

a transparent peer-reviewed process that is open to the public during the deferral period but not 

as part of this deferral rulemaking. Regarding forest residues and spent pulping liquor, EPA 

agrees that these feedstocks are within the scope of the current definition.

Comment:

Commenter 0108.1 stated that using open-loop biomass (waste biomass) for bio-power 

production releases carbon faster into the atmosphere than would have occurred naturally. The 

commenter agrees that the biogenic carbon emissions should be counted when determining PSD 

and Title V applicability, but that a significant discount compared to fossil fuel CO2 emissions

should be applied.

Commenter 0023D highlighted the benefits of open-loop biomass fuels, agreed with 

the proposed deferral to allow EPA to define the science of open-loop biomass (waste biomass), 

and discussed regulatory and market challenges that the biomass industry faces.

Commenter 0108.1 stated that any biomass harvested and collected through an open-loop 

process (waste biomass) must be replenished on a sustainable basis. Crops like perennial grasses 

can yield up to 10 dry tons per acre, per year by its second or third year of growth. Trees, on the 

other hand, have a slower rate of growth, and even the fastest-growing varieties are about half as

productive as grasses. Therefore, crops that are faster growing should be advantaged through 

some form of credit, as a means to reward the grower for removing CO2 faster and repaying the 

carbon “mortgage” that is created from the primary combustion of open-loop woody biomass 

more rapidly and more efficiently than replanting trees, for example.
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

31

Response: We acknowledge that different accounting considerations may be warranted for 

different types of feedstocks but such considerations are beyond the scope of this rulemaking. 

Various types of “open-loop biomass” will be considered along with other feedstocks as we 

study accounting methods for biogenic CO2 from stationary sources over the next three years.

Comment: Commenter 0064.1 noted that when forest biomass is used to generate energy, as a 

fossil fuel substitute, new CO2 emissions from fossil fuels are replaced by emissions that are 

already part of the closed-loop carbon cycle. The commenter also noted that biomass is often 

produced when over-crowded forests are thinned in order to improve the productivity and fire 

resiliency of forests. In so doing, the forests are better able to absorb and store more carbon over 

time.

Response:

6.5 Wastewater Treatment CO2

 EPA acknowledges that different accounting considerations may be warranted for 

different types of biomass feedstocks. We are considering the issues the commenter raises as we 

conduct a detailed examination of the science and technical issues associated with biogenic CO2

emissions, and the net atmospheric impact of such emissions, and develop an accounting 

framework that is scientifically sound and manageable in practice. 

Comment:

Commenter 0099.1 provided several reasons why waste-derived biofuels should be considered 

separate from other biofuel sources:

Commenters 0053.1, 0099.1, and 0117.1 stated that waste-derived biogas is a green 

renewable energy resource that should continue to be promoted as an environmentally friendly 

alternative to fossil fuel and that regulation of biogenic emissions from combustion of biogas 

only serves as a disincentive to renewable energy production and use. Commenter 0053.1 

discussed benefits of using biogas derived from wastewater treatment, referring to wastewater 

treatment practices and the California Air Resources Board (CARB) low carbon fuel standard

(LCFS). The commenter noted that regulating biogenic CO2 emissions under Title V and PSD 

would inhibit green energy and green fuel development and would stop projects that could 

reduce GHG emissions by displacing fossil fuel and converting methane to energy and biogenic 

CO2. 

• Waste-derived biofuels are largely generated locally, requiring little transportation to get 

the fuel to market;

• There is no competing land use impact;

• There is no possibility of carbon stock reversal, as with other sources of biomass; and 

• Sewage is a “must manage” waste. If this decomposition of organic material happens in 

nature, then no energy benefit is realized. However, by managing and accelerating 

decomposition in a controlled environment such as a landfill or wastewater treatment 

plant, potential is created for renewable energy.

Commenter 0099.1 noted that biogas contains approximately 40 percent CO2 and 60 percent 

methane. Some publicly owned treatment works (POTWs) use biosolids for energy generation. 

Biogas and biomass at wastewater facilities have significantly lower carbon pathways when 

compared to other commercial biomass energy production, particularly in the transportation fuels 
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

32

sector. The CARB, under AB32, has adopted a low carbon fuel standard that treats 

compressed/liquefied natural gas (C/LNG) produced from biogas as having the lowest carbon 

intensity of all transportation fuels that were evaluated.

Response: EPA acknowledges the comment and notes that the final rule defers for three years 

the application of PSD and Title V permitting requirements to biogenic CO2 emissions. EPA 

also acknowledges that different accounting considerations may be warranted for different types 

of biomass feedstocks. In addition, EPA recognized in the preamble of the proposal that the 

potential may exist for it to determine that multiple types of biomass feedstocks would have a 

negligible impact on the net carbon cycle, and that CO2 emissions from such feedstocks would 

result in a negligible net atmospheric impact. In particular, EPA noted that this may apply to 

residue or byproduct material that if not used as a bioenergy feedstock would have decomposed 

under natural circumstances in a relatively short period of time. We are considering the issues the 

commenter raises as we conduct a detailed examination of the science and technical issues 

associated with biogenic CO2 emissions, and the net atmospheric impact of such emissions, and 

develop an accounting framework that is scientifically sound and manageable in practice. 

Comment: Commenter 0117.1 stated that the deferral of biogenic CO2 emissions from CAA 

permitting programs should specifically include both combustion and non-combustion sources of 

biogenic CO2. In the proposed rule, combustion of biosolids and biogas are specifically listed as 

exclusions, but wastewater treatment process emissions are not mentioned. The commenter 

stated that wastewater treatment is a vital natural function that cannot be stopped, and utilities 

should therefore not be penalized for biogenic CO2 emissions resulting from the mandatory 

treatment of these wastes, adding that composting should be included as well, since its wastederived emissions are part of the same short-term carbon cycle.

Response:

6.6 Co-firing Fuel Mixtures

 The final rule includes the deferral of biogenic CO2 emissions resulting from the 

decomposition of organic material during wastewater treatment processes. The language of the 

final rule states that the deferral applies to “...carbon dioxide emissions resulting from the 

combustion or decomposition of non-fossilized and biodegradable organic material originating 

from plants, animals, or micro-organisms (including products, by-products, residues and waste 

from agriculture, forestry and related industries as well as the non-fossilized and biodegradable 

organic fractions of industrial and municipal wastes, including gases and liquids recovered from 

the decomposition of non-fossilized and biodegradable material)” (emphasis added). The 

inclusion of the phrase “including gases and liquids recovered from the decomposition of nonfossilized and biodegradable organic material” does not limit the language that precedes it. 

Comment: Commenters 0023J, 0063.1, and 0086.1 stated that in the proposal, EPA indicated 

the deferral will apply to biogenic CO2 emissions from biogenic feedstocks and is not limited to 

specific types of facilities. The commenters agreed that EPA should not limit the deferral based 

on the type of facility, and should apply the deferral to the biogenic fraction of CO2 emissions 

from projects planning to use mixtures of fossil fuels and biogenic fuels. 

Response: The final rule does not limit the deferral of biogenic CO2 emissions based on the 

type of facility from which such emissions originate. In addition, as was stated in the preamble to 
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

33

the proposal, the preamble to the final rule reiterates that for facilities that co-fire biologicallybased fuels and fossil fuels, and/or mixed fuels, the biogenic CO2 emissions from combustion are 

included in the deferral and the fossil CO2 emissions are not. 

6.7 Municipal Solid Waste Considerations

Comment: Commenter 0062.1 urged EPA to finalize its proposed deferral and to include the 

solid waste management sector in its evaluation of alternative accounting approaches for 

biogenic GHG emissions. The commenter noted that although the entire waste sector contributes 

only about two percent of total U.S. GHG emissions, landfills will be disproportionately 

impacted by the Tailoring Rule. The commenter stated that for their organization alone, the PSD 

permitting program will apply to approximately one-third of active landfills at some point in the 

future based on potential GHG emissions that include biogenic CO2.

Response: EPA acknowledges that different accounting considerations may be warranted for 

different types of biomass feedstocks. In addition, EPA recognized in the preamble of the 

proposal that the potential may exist for it to determine that multiple types of biomass feedstocks 

would have a negligible impact on the net carbon cycle, and that CO2 emissions from such 

feedstocks would result in a negligible net atmospheric impact. We are considering the issues the 

commenter raises as we conduct a detailed examination of the science and technical issues 

associated with biogenic CO2 emissions, and the net atmospheric impact of such emissions, and 

develop an accounting framework that is scientifically sound and manageable in practice.

Comment: Commenters 0059.1 and 0116.1 stated that use of MSW biomass as an energy 

source is different from the use of many other types of biomass, because not all sources of 

biomass reduce emissions equally on a lifecycle basis. Commenter 0116.1 articulated that EPA’s 

Municipal Solid Waste Decision Support Tool shows that WTE results in significant 

displacement of fossil fuels and is superior to land-filling from an environmental and energy 

perspective (including a net reduction in GHG emissions). However, the cost burden for WTE 

projects is already proportionally higher than land-filling, and Title V permitting could 

discourage the environmentally preferable option. Commenter 0116.1 provided several 

references in support of the environmental and GHG-mitigating benefits of WTE relative to

land-filling. Commenter 0059.1 argued that direct and indirect emissions from land-use changes 

must be considered when assessing sustainability of many biogenic feedstocks, and referred to a 

study that concluded across-the-board exemption of biogenic CO2 is inappropriate without 

consideration of emissions due to land-use changes. However, the commenter pointed out that 

the use of biogenic MSW is widely accepted as carbon neutral, because MSW is not harvested or 

grown, and that EPA made this same point in the preamble to the RFS rule in March 2010,

stating that renewable fuel produced from feedstocks consisting of wastes that would normally 

be discarded should be assumed to have little or no land-use emissions of GHG.

Response: EPA acknowledges that different accounting considerations may be warranted for 

different types of biomass feedstocks. In addition, EPA recognized in the preamble of the 

proposal that the potential may exist for it to determine that multiple types of biomass feedstocks 

would have a negligible impact on the net carbon cycle, and that CO2 emissions from such 

feedstocks would result in a negligible net atmospheric impact. We are considering the issues the 

commenter raises as we conduct a detailed examination of the science and technical issues 
6.0 Biomass-Related Definitions and Affected Industries in the Deferral Rule

34

associated with biogenic CO2 emissions, and the net atmospheric impact of such emissions, and 

develop an accounting framework that is scientifically sound and manageable in practice.

Comment: Commenter 0080.1 stated that EPA did not examine the regulatory burdens 

associated with extending PSD and Title V requirements to biogenic CO2 from modern landfills 

in the Tailoring Rule. Commenters (0062.1 and 0080.1) stated that conventional landfill projects 

without energy recovery have not triggered PSD, since the primary pollutant is non-methane 

organic compounds (NMOCs) and pointed out that EPA programs for control of NMOCs from 

landfills have prompted voluntary landfill gas-to-energy (LFGTE) projects with higher CO2

emissions than flares. Commenter 0062.1 indicated that LFGTE projects have triggered PSD 

permitting primarily for carbon monoxide emissions and to a lesser extent for nitrogen oxides 

(NOx) emissions. Engine- and turbine-based LFGTE projects tend to have significantly higher 

carbon monoxide (CO) and NOx emissions than flares when burning landfill gas, and the 

siloxanes entrained in landfill gas preclude the use of stack emissions control technology.

Commenter 0080.1 stated that without the deferral and subsequent permanent exemption of 

biogenic CO2, recent EPA actions will result in more LFGTE projects triggering PSD and deter 

such projects and the reductions in methane emissions that come with such projects.

Response: EPA acknowledges the comments and notes that the final rule defers for three years 

the application of PSD and Title V permitting requirements to biogenic CO2 emissions, including 

biogenic CO2 emissions from LFGTE projects. 

Comment: Commenter 0062.1 referenced an EPA Office of Solid Waste lifecycle assessment 

that concluded accounting for and regulating biogenic GHG emissions from solid waste 

management would result in double-counting, because at the point of waste generation

reductions in the carbon sink due to harvesting wood or plant material and manufacturing a 

consumer product have already been accounted for.

Response: While double counting of biogenic CO2 emissions may be an issue addressed within 

the context of the OSW lifecycle assessment, this does not necessarily mean that emissions 

would be double counted in the PSD and Title V programs and it is beyond the scope of this 

rulemaking. EPA will evaluate the issues the commenter raises during its detailed examination 

of the science and technical issues associated with accounting for biogenic CO2 emissions.
7.0 Pollutants Included in Deferral

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7.0 Pollutants Included in Deferral

7.1 Non-CO2 GHG and Non-GHG Pollutants

Comment: Commenters 0070.1 and 0144.1 suggested that the biogenic deferral, and eventually 

permanent biogenic exemption should apply on a CO2e basis because the GWP of the non-CO2, 

GHG emissions is typically small compared to the CO2 emitted during biogenic combustion. 

The commenter stated that inclusion of CH4 and nitrous oxide (N2O) in the deferral would 

promote the construction of biomass facilities and comport with state renewable energy 

standards. Commenter 0070.1 also stated that an alternative approach is to deem CH4 and N2O 

de minimis for purposes of the threshold determination, so as not to undermine EPA’s stated 

purpose for proposing the deferral.

Response: While CH4 and N2O are produced when biomass is combusted, the level of 

emissions and resulting impact on atmospheric concentrations of these gases are primarily 

related to the feedstock handling and combustion conditions at the specific plant rather than to 

the source of the feedstocks. We finalized this rule as proposed and included only biogenic CO2

emissions for this reason, and we note further that emissions of non-CO2 GHGs are typically a 

small proportion of the total GHG emissions from combustion of biologically based material. 

Since the non-CO2 GHGs are so small relative to CO2, the deferral of biogenic CO2 emissions 

will ensure the biomass combustion projects will likely not meet the applicability thresholds 

based on their CH4 and N2O emissions alone.

Comment: Commenter 0094.1 urged EPA to expand the scope of the detailed scientific review 

that will be conducted during the deferral to include an evaluation of issues associated with all 

biogenic emissions, including methane from landfills. Currently EPA’s rules require, in most 

instances, that a gas collection system be installed and routed to a flare when the capacity of a 

landfill reaches a certain threshold. Prior to this point, landfills may be subjected to a PSD permit 

review based on their ultimate potential to emit methane. However, since the control 

requirement would likely be a gas collection system and a flare, which would convert the 

methane to CO2, the same issues associated with combustion of a biogenic feedstock would still 

need to be addressed only now it would be after the permitting process is complete.

Response: As noted in Section III of the preamble, the deferral will give EPA time to complete 

its work including a detailed examination of the scientific and technical issues associated with 

accounting for biogenic CO2 emissions from stationary sources and any subsequent rulemakings. 

The proposed rule addresses issues from methane sources, noting in Section III.A.5 of the 

proposal preamble, that the combustion of CH4-laden biogas (e.g., from landfills or other large 

sources of methane) for energy-production reduces overall CO2e emissions because of the higher 

GWP for CH4. 

Comment: One commenter (0102.1) disagreed with the statement in Section III.C of the 

proposal that “... non-CO2 GHG do not participate in natural biogeochemical carbon cycles as 

CO2 does...” This commenter stated that methane is part of the global carbon cycle; nitrous 

oxide emissions and removals are a part of the global nitrogen cycle. The commenter requested 

that the sentence be revised to reflect current scientific understanding.
7.0 Pollutants Included in Deferral

36

Response: We have revised this text in the preamble to the final rule. We emphasize that while 

CH4 and N2O are produced when biomass is combusted, the level of emissions and resulting 

impact on atmospheric concentrations of these gases are primarily related to the feedstock 

handling and combustion conditions at the specific plant rather than to the source of the 

feedstocks. 

Comment: Commenter 0143.1 contended that if EPA’s CO2 permitting exemption is allowed to 

stand there will be a large increase in emissions of particulates and other toxic air pollutants from 

biomass combustion. The commenter provided numerous examples of the health impacts of 

biomass emissions, citing several prominent health organizations. Similarly, commenter 0182 

noted that biomass incinerators release more particulate, particularly fine particulate, requiring 

more use and disposal of water for scrubbers.

Response: We agree that EPA regulations should address harmful health impacts; however, the 

CAA does not always give EPA authority to consider health impacts as part of the regulatory 

development process for particular regulations. As noted in Section III of the preamble, the 

deferral will give EPA time to complete its work including a detailed examination of the 

scientific and technical issues associated with accounting for biogenic CO2 emissions from 

stationary sources and any subsequent rulemakings. This rule does not address emissions of 

other particulates and other toxic air pollutants.

Comment:

Commenter 0056.1 suggested that the lifecycle analysis of biogenic methane should be included 

in EPA’s overall carbon lifecycle analysis of biogenic emissions.

 Commenter 0093.1 recommended that EPA consider not CO2 emissions but carbon 

emissions for deferral, and defer regulation of all stationary source biogenic carbon emissions: 

biogenic CH4, biogenic CO and non-methane hydrocarbon emissions. These carbon emissions 

are part of the natural carbon cycle as well as part of bioenergy applications, and if the energy 

alternative produces a net reduction in the CH4 emissions associated with biomass recycling, 

credit should be given for that reduction.

Response:

7.2 Fugitive Emissions

 While CH4, N2O, and other hydrocarbons are produced when biomass is combusted, 

the level of emissions and resulting impact on atmospheric concentrations of these gases are 

primarily related to the feedstock handling and combustion conditions at the specific plant, rather 

than to the source of the feedstocks. We finalized this rule as proposed and included only 

biogenic CO2 emissions for this reason, and we note further that emissions of non-CO2 GHGs are 

typically a small proportion of the total GHG emissions from combustion of biologically based 

material. Since the non-CO2 GHGs are so small relative to CO2, the deferral of biogenic CO2

emissions will ensure the biomass combustion projects will likely not meet the applicability 

thresholds based on their CH4 and N2O emissions alone. Further, in Section III.A.5 of the 

proposal preamble, we note that combustion of CH4-laden biogas for energy-production reduces 

overall CO2e emissions because of the higher GWP for CH4. 

Comment: Commenter 0080.1 noted that at the present time, there are no accepted or approved 

methodologies for determining the site specific sources of biogenic CO2 at solid waste 

management facilities. Area sources like landfills and compost facilities are highly complex 
7.0 Pollutants Included in Deferral

37

sources, and CO2 emissions are emitted from a variety of locations. A recent report found that 

these emissions can only be estimated, but not quantified. Before EPA imposes GHG accounting 

at waste management facilities, a standardized approach should be developed, along with reliable 

and accurate test methods, considering the cost implications of mandating such requirements.

Response:

As mentioned in Section II.D of the preamble, the three-year deferral period for regulation of 

biogenic CO2 emissions under PSD was proposed so the Agency can develop an appropriate 

accounting methodology that satisfies the principles of predictability, practicality, and scientific 

soundness. Should it be necessary, EPA proposes in the future to implement an appropriate 

accounting methodology through notice-and-comment rulemaking within the three-year

timeframe. Comments about particular emissions estimation or determination methods or the 

application of future permitting requirements to a particular source or source category are outside 

the scope of this rulemaking.

 The commenter asserts that there are no accepted or approved methodologies for 

determining the sources of biogenic CO2 at solid waste facilities. There are, however, existing 

methods for direct measurement of CO2 in collected landfill gas. While methodologies for 

estimating CO2 emissions from composting are less developed than for landfills, estimating these 

emissions is somewhat easier than for landfills because essentially all of the carbon loss from the 

waste is emitted as CO2. 
8.0 Duration of Deferral and Permitted Activities During Deferral

38

8.0 Duration of Deferral and Permitted Activities During Deferral

8.1 Deferral Start Date

Comment: Multiple commenters (0023J, 0062.1, 0080.1, 0086.1, and 0091.1) supported 

finalization of the proposed deferral prior to July 1, 2011. Commenter 0086.1 added that EPA 

should defer the July 1, 2011 trigger date entirely until pending petitions for reconsideration and 

pending court cases are resolved, and because States are not prepared to implement the 

permitting program. Commenter 0062.1 stated the deferral was necessary to prevent triggering 

permit requirements for a large number of new municipal waste management facilities.

Response: This rule defers the application of the PSD and Title V programs to biogenic CO2

emissions for three years. The dates, thresholds and other requirements established in the 

Tailoring Rule remain unchanged and are not a subject of this rulemaking. 

Comment:

A source or modification that would be major only for GHGs must begin actual construction 

prior to July 1, 2011, in order to avoid PSD applicability for GHGs and for all other 

attainment pollutants that trigger the significance levels. 

 Commenter 0079.1 stated that EPA should not only defer regulation of biogenic 

CO2 but also completely eliminate the July 1, 2011, date for GHG to trigger PSD permitting 

requirements, because states are not prepared to implement the program and in light of pending 

petitions for reconsideration of EPA’s statutory thesis for GHG. The commenter cited EPA 

permitting determinations that deferred the January 2, 2011 trigger date for certain sources as 

evidence that the Tailoring Rule schedule moves too quickly to implement PSD for GHG and 

contrasted this previous deferral with statements in the final Tailoring Rule. The commenter 

stated that there is even greater justification for deferring the July 1, 2011 trigger date, which 

brings far more sources into the program, than the January 2, 2011 trigger date. The commenter 

summarized the Tailoring Rule as follows: 

Based on the Step 2 deadline the commenter observed that many states have a significant minor 

NSR permitting backlog and obtaining the required permits to begin construction may not be 

possible based on routine permitting time frames of a year or more for minor NSR permits. The 

commenter further stated that the useful timeframe was further constrained by EPA’s 

requirement that construction must commence prior to July 1, and stated that EPA was 

“incorrect” in statements that the Tailoring Rule provided sufficient time for sources to “begin

actual construction” before July 1, 2011. The commenter closed stating that EPA should defer 

the July 1, 2011, trigger date at least until the litigation is resolved and no sooner than 2013, 

because by 2013, the litigation in the United States Court of Appeals for the D.C. Circuit 

challenging EPA’s suite of GHG rules should be resolved and EPA will be able to provide 

sources with more certainty regarding the applicable regulatory requirements.

Response: This rule defers the application of the PSD and Title V programs to biogenic CO2

emissions for three years. The dates, thresholds and other requirements established in the 

Tailoring Rule remain unchanged and are not a subject of this rulemaking. 
8.0 Duration of Deferral and Permitted Activities During Deferral

39

8.2 Permanent Exemption

Comment: Several commenters (0023B, 0023D, 0023K, 0052.1, 0054.1, 0064.1, 0070.1, 

0084.1, 0086.1, 0089.1, 0117.1, 0122.1, 0126.1, 0103.0, 0139.1, 0140.1, 0144.1) generally 

supported the proposed deferral while maintaining that the proper long-term solution is 

permanent exemption based on both scientific and administrative issues related to biogenic CO2

emissions. Two commenters (0117.1 and 0023B) stated that permanent exemption will re-align 

CAA permitting programs with major GHG regulatory and policy programs worldwide.

Commenter 0126.1 also provided a legal rationale justifying a permanent exemption. Commenter 

0023B added that permanent exemption would avoid placing burdensome regulations and costs 

on fuel ethanol, a far better environmental alternative to fossil fuels. Commenter 0023K also 

specifically supported permanent exemption of biogas and bio-solids from wastewater treatment. 

Commenter 0089.1 noted that biomass fuels derived from forestry wastes and other biomass 

materials that have been clearly demonstrated to be carbon neutral could be permanently 

exempted.

Response: This rulemaking defers the application of the PSD and Title V programs to biogenic 

CO2 emissions for a period of three years because that is the amount of time EPA has determined 

is necessary to complete its work and the commenters have not provided sufficient information 

to suggest otherwise. EPA is conducting a detailed examination of the science and technical 

issues associated with accounting for biogenic CO2 emissions. Once that work is complete the 

Agency intends to undertake a rulemaking to establish the treatment of these emissions in the 

PSD and Title V programs. At this time, we do not have enough information or analysis to 

establish a permanent accounting methodology or permanent exclusions, inclusion, or other 

treatment for biogenic CO2 emissions, even emissions from certain types of feedstocks, in the 

PSD and Title V programs. We also note, as explained in the preamble, that it is possible that 

the subsequent rulemaking, depending on the nature of EPA’s determinations, would supersede 

this rulemaking and become effective in fewer than three years.

Comment: Commenter 0332.1 stated that for certain types of biomass, the climate benefits are 

clear and there is little scientific debate about their carbon neutrality. The commenter believes 

that bioenergy producers who use these types of biomass should be exempted from the Tailoring 

Rule regulations and thus, be released from the threat of future regulatory action under the 

Tailoring Rule – a threat which now creates uncertainty for farmers, forest owners, bioenergy 

producers, investors, workers, and communities. Commenter 0089.1 also supported a permanent 

exemption for certain types of biomass fuels that have been demonstrated to be carbon neutral, 

and recommended EPA apply the deferral only to those biomass fuels where EPA needs to 

resolve the uncertainty of impact on the carbon cycle.

Response: EPA is considering the issues the commenter raises as it conducts it detailed 

examination of the science and technical issues associated with accounting for biogenic CO2

emissions. As stated in the preceding response, once that work is complete the Agency intends 

to undertake a rulemaking to establish the treatment of these emissions in the PSD and Title V 

programs. We have determined that three years will be required to complete the scientific work 

as well as the follow-on rulemaking. However, we would also note, as explained in the preamble, 

it is possible that the subsequent rulemaking, depending on the nature of EPA’s determinations, 

would supersede this rulemaking and become effective in fewer than three years.. At this time, 
8.0 Duration of Deferral and Permitted Activities During Deferral

40

we do not have enough information or analysis to establish a permanent accounting methodology 

or permanent exclusion, inclusion or other treatment for biogenic CO2 emissions, even those 

emissions from certain types of feedstocks, in the PSD and Title V programs.

8.3 Three-Year Deferral Period

Comment: Commenter 0014.1 rejected EPA’s explanation that the proposed deferral timeframe 

is due to difficulties in accounting for different types of biogenic feedstocks, because “this is not 

directly linked to biogenic emissions” at a specific source within the current paradigm for 

permitting individual stationary sources on a case-by-case basis. The commenter felt this 

explanation should not be used to justify relaxation of existing permitting requirements for 

stationary sources for three years.

Response: EPA disagrees with the commenter’s view that this action is unsupported by the law 

or science. As EPA explained in the preamble, this interim deferral represents a permissible 

application of well-established administrative law doctrines, necessitated by the scientific 

uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a regulatory 

scheme that implements the CAA in a step-wise fashion designed to minimize administrative 

burdens and avoid unnecessary regulation of de minimis sources of air pollution. Subsequent 

regulations to establish treatment of specific sources of biogenic emissions under the PSD and 

Title V programs, based on the results of the study and development of the accounting 

framework, are beyond the scope of this action.

Comment: One commenter (0355) believes EPA’s deferral should only last for one year, and 

stressed that EPA must commit the necessary resources to complete these studies. Commenter 

0049.1 suggested EPA reduce the study period to 2 years, and then develop PSD and Title V 

regulations for bioenergy sources, after completing an environmental analysis to support the 

regulations.

Response:

We also note, as explained in the preamble, that it is possible that the subsequent rulemaking, 

depending on the nature of EPA’s determinations, would supersede this rulemaking and become 

effective in fewer than three years.

 EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. Once that work is complete the Agency 

intends to undertake a rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. We have determined that three years will be required to complete the 

scientific work as well as the follow-on rulemaking, and the commenter has not provided 

information to suggest otherwise. 

Comment: One commenter (0145.1) stated that the biomass industry already exploits CAA 

loopholes, avoiding BACT determinations. The commenter provided a list of facilities and 

alleges that they have unlawfully obtained “minor source status” to avoid PSD permitting and the 

Tailoring Rule, even though their emissions exceed Tailoring Rule thresholds. Instead of 

exempting biomass energy for 3 years, EPA should conduct a wholesale examination of the 

manner in which the industry is escaping PSD permitting and the fact that this is being 

sanctioned by the states.
8.0 Duration of Deferral and Permitted Activities During Deferral

41

Response: This rulemaking defers the application of the PSD and Title V programs to biogenic 

CO2 emissions for a period of three years. Facilities with minor source permits and the other 

issues raised by the commenter are beyond the scope this rulemaking. 

Comment: Commenter 0074.1 supports the deferral and notes that EPA has ample legal 

authority to finalize the proposal. The commenter maintains that EPA must remove the 

automatic sunset date from the final deferral rule based on concerns that EPA may not be able to 

complete all required analyses and related rulemaking procedures within three years.

Response:

We do not agree with the commenter’s suggestion to remove the automatic sunset provision. 

This deferral is intended to be a temporary measure to allow the Agency time to complete its 

work and determine what, if any, the treatment of biogenic CO2 emissions should be in the PSD 

and Title V programs. This action is not the Agency’s final determination on the treatment of 

biogenic CO2 emissions in those programs. 

 EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. Once that work is complete the Agency 

intends to undertake a rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. We have determined that three years will be required to complete the 

scientific work as well as the follow-on rulemaking, and the commenter has not provided 

information to suggest otherwise. In fact, as explained in the preamble, it is possible that the 

subsequent rulemaking, depending on the nature of EPA’s determinations, would supersede this 

rulemaking and become effective in fewer than three years.

Comment: Commenter 0062 supports deferral and a public review of biogenic carbon neutrality 

while emphasizing the time critical need to promulgate the deferral prior to July 1, 2011.

Response: EPA thanks the commenter for their comment. We have made every attempt to 

finalize this deferral as close to July 1, 2011 as possible. 

Comment: Commenter 0070.1 stated that as an initial step, EPA should defer for a period of 

three years application of PSD and Title V regulations to biogenic CO2 emissions because 

biogenic CO2 differs from fossil CO2 in the time required to replenish carbon reservoirs.

Response: This rulemaking defers the application of the PSD and Title V programs to biogenic 

CO2 emissions for a period of three years.

Comment: Commenter 0082.1 stated that EPA should extend deferral until final rulemaking is 

complete to avoid encumbering potential investments in projects and associated jobs with 

uncertainty regarding whether issues identified in the deferral can be resolved within three years.

Response: EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. Once that work is complete the Agency 

intends to undertake a rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. We have determined that three years will be required to complete the 

scientific work as well as the follow-on rulemaking, and the commenter has not provided 

information to suggest otherwise. In fact, as explained in the preamble, it is possible that the 
8.0 Duration of Deferral and Permitted Activities During Deferral

42

subsequent rulemaking, depending on the nature of EPA’s determinations, would supersede this 

rulemaking and become effective in fewer than three years. We do not agree with the 

commenter’s suggestion to remove the automatic sunset provision. This deferral is intended to 

be a temporary measure to allow the Agency time to complete its work and determine what, if 

any, the treatment of biogenic CO2 emissions should be in the PSD and Title V programs. This 

action is not the Agency’s final determination on the treatment of biogenic CO2 emissions in 

those programs. 

Comment: Commenter 0086.1 supports deferral based on carbon neutrality while expressing 

concerns that EPA must take additional actions to ensure the three-year deferral can be 

effectuated considering existing State regulations that cannot be revised by July 1, 2011.

Response:

With this final rule, states may require additional time to review their state laws to incorporate 

the deferral. To the extent no such deferral is available under the PSD permitting regulations 

applicable at the time a permitting authority issues a PSD permit for a bioenergy facility EPA has 

issued guidance entitled, “Guidance for Determining Best Available Control Technology for 

Reducing Carbon Dioxide Emissions from Bioenergy Production”. The guidance is provided to 

help permitting authorities establish a basis for concluding that under PSD Programs the 

combustion of biomass fuels can be considered BACT for biogenic CO2 emissions at stationary 

sources. 

This rulemaking defers the application of the PSD and Title V programs to biogenic 

CO2 emissions for a period of three years because that is the amount of time EPA has determined 

it is necessary to complete its work.

Comment: Commenter 0084.1 declared that EPA should defer applicability of PSD/Title V to 

biogenic GHG emission on the basis of common sense. The commenter quoted the preamble to 

the proposal, “EPA has sufficient information at this time to conclude that at least some biomass 

feedstocks that may be utilized to produce energy have a negligible impact on the net carbon 

cycle ....” The commenter stated that EPA believes it can come to a decision on the remaining 

biomass feedstocks within three years. The commenter asserted that if EPA were to adopt the 

deferral, PSD/Title V would apply at the end of those three years automatically to biogenic CO2

emissions from all sorts of combustion or decomposition processes. The commenter stated that 

this would be arbitrary and capricious and would be impossible to justify upon judicial review. 

Commenter 0084.1 stated that EPA should instead defer PSD/Title V indefinitely and bring any 

cases of net carbon contribution by biogenic materials within the domain of major permitting 

programs on a case-by-case basis through rulemaking. The commenter further contended that a 

three-year period is far too short for the amount of work EPA anticipates.

Response: EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. Once that work is complete the Agency 

intends to undertake a rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. We have determined that three years will be required to complete the 

scientific work as well as the follow-on rulemaking, and the commenter has not provided 

information to suggest otherwise. In fact, as explained in the preamble, it is possible that the 

subsequent rulemaking, depending on the nature of EPA’s determinations, would supersede this 

rulemaking and become effective in fewer than three years.
8.0 Duration of Deferral and Permitted Activities During Deferral

43

This deferral is intended to be a temporary measure to allow the Agency time to complete its 

work and determine what, if any, the treatment of biogenic CO2 emissions should be in the PSD 

and Title V programs. This action is not the Agency’s final determination on the treatment of 

biogenic CO2 emissions in those programs. 

Comment: Commenter 0014.1 is concerned that the deferral might slow development of control 

technologies for small sources, if major sources are not required to comply with BACT. 

Commenter 0014.1 also expressed concerns about new major sources of biogenic CO2 emissions 

being constructed in marginally attainment or not-attainment areas and stated that these concerns 

warrant only a two year deferral.

Response: This rulemaking defers the application of the PSD and Title V programs to biogenic 

CO2 emissions for a period of three years because that is the amount of time EPA has determined 

it is necessary to complete its work. Technology development and attainment/non-attainment 

issues are outside the scope of this rulemaking. 

Comment: Commenter 0150.1 opposed deferral and stated that there is no need to defer for 

three years because the science of accounting for carbon from burning wood is well known and 

the concept of biogenic carbon neutrality is “based on a host of false assumptions”; see EPAHQ-OAR-2011-0083-0150.2, -0150.3, -0150.4, and -0150.5.

Response: EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. Once that work is complete the Agency 

intends to undertake a rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. We have determined that three years will be required to complete the 

scientific work as well as the follow-on rulemaking, and the commenter has not provided 

information to suggest otherwise. In fact, as explained in the preamble, it is possible that the 

subsequent rulemaking, depending on the nature of EPA’s determinations, would supersede this 

rulemaking and become effective in fewer than three years. This deferral is intended to be a 

temporary measure to allow the Agency time to complete its work and determine what, if any, 

the treatment of biogenic CO2 emissions should be in the PSD and Title V programs. This action 

is not the Agency’s final determination on the treatment of biogenic CO2 emissions in those 

programs. 

Comment: Commenter 0142.1 believes the decision to propose a three-year deferral was 

arbitrary and capricious. The proposal to delay and in the interim to consider bioenergy of all 

types to be best available technology appears to be driven by forces and factors other than what a 

large body of scientific research and the precautionary principle indicates. If this deferral is 

granted, the science indicates there is a strong possibility for irreversible damage to be done to 

the climate, and therefore should be reconsidered. The commenter also questions the rationale 

behind the length of time chosen for the deferral, which appears too arbitrary and lengthy, and 

specifically asks why three years was chosen. 

Response: This rulemaking defers the application of the PSD and Title V programs to biogenic 

CO2 emissions for a period of three years because that is the amount of time EPA has determined 

it is necessary to complete its work, not an arbitrary and capricious time period, as the 

commenter suggests. In fact, as explained in the preamble, it is possible that the subsequent 
8.0 Duration of Deferral and Permitted Activities During Deferral

44

rulemaking, depending on the nature of EPA’s determinations, would supersede this rulemaking 

and become effective in fewer than three years.

This deferral is intended to be a temporary measure to allow the Agency time to complete its 

work and determine what, if any, the treatment of biogenic CO2 emissions should be in the PSD 

and Title V programs. This action is not the Agency’s final determination on the treatment of 

biogenic CO2 emissions in those programs. 

During the deferral period, EPA is conducting a detailed examination of the science and 

technical issues associated with accounting for biogenic CO2 emissions. Once that work is 

complete the Agency intends to undertake a rulemaking to establish the treatment of these 

emissions in the PSD and Title V programs. During that process, EPA may find that some 

sources of biogenic CO2 emissions have a de minimus effect on atmospheric CO2. 

It is true that stationary sources that combust biomass and construct or modify during the threeyear deferral period will avoid the application of PSD to the biogenic CO2 emissions resulting 

from those actions. However, at this time, we are unable to predict which biogenic CO2 sources, 

if any, currently subject to the deferral would be subject to any permanent exemptions, or which 

currently deferred sources would be potentially required to account for their emissions in relation 

to future permitting actions as a result of the future rulemaking. Thus, we do not have enough 

information at this time to consider the effects of allowing or not allowing such grandfathering. 

Comment: Commenter 0056.1 supported an extension of the proposed deferral to a total of five 

years, from the currently proposed three years, because the analysis needed to characterize the 

life-cycle emissions and pathways of biogenic activities will require additional time beyond the 

three years envisioned, owing to the complexity of life-cycle emission calculations and the 

myriad processes that require evaluation, and when the additional time for regulatory proposal 

and finalization is considered (12-18 months), it becomes clear that three years is inadequate to 

properly characterize and codify a task of this complexity. In order to ensure that EPA prepares a 

complete, scientifically sound, and defensible analysis, the commenter recommends a minimum 

5-year duration for this deferral.

Response:

8.4 Scientific Examination

EPA is considering the issues the commenter raises as it conducts a detailed 

examination of the science and technical issues associated with accounting for biogenic CO2

emissions. Once that work is complete the Agency intends to undertake a rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. We have 

determined that three years will be required to complete the scientific work as well as the followon rulemaking, rather than five years as the commenter suggests. In fact, as explained in the 

preamble, it is possible that the subsequent rulemaking, depending on the nature of EPA’s 

determinations, would supersede this rulemaking and become effective in fewer than three years.

Comment: Commenter 0047.1 stated a proper study is needed to determine if fossil and 

biogenic CO2e should be treated differently under the Tailoring Rule, and requested that EPA 

perform a thorough and expeditious review of the available science related to biogenic CO2

emissions. Commenter 0032 recommended that EPA engage with state forestry and agriculture 
8.0 Duration of Deferral and Permitted Activities During Deferral

45

agencies as non-federal expert partners during scientific review of biogenic CO2 emissions. 

Commenter 0059.1 encouraged EPA to include a representative from the MSW management 

industry. Commenter 0062.1 recommended that the EPA include solid waste management 

experts from academia and the public and private sectors and offered to provide suggested 

experts for the Agency’s deliberation.

Response:

On April 27, 2011, EPA’s SAB published a notice soliciting experts for a peer review of EPA’s 

science and technical work on biogenic CO2 emissions. The commenter should contact the SAB 

directly with any questions, comments or suggestions. 

 EPA is considering the issues the commenter raises as it conducts it detailed 

examination of the science and technical issues associated with accounting for biogenic CO2

emissions. EPA intends to provide their work to the Science Advisory Board (SAB) for peer 

review later in 2011. The SAB is serving as the “independent scientific panel” cited in proposed 

deferral. The public will have the opportunity to provide comments for SAB consideration. 

Comment: Commenters 0043.1 and 0054.1 recommended that EPA take the full three-year

deferral period to evaluate how to regulate biogenic stationary sources of CO2. Commenter 

0050.1 stated it is appropriate for EPA to seek more time to examine technical and accounting 

issues related to biomass emissions, to collaborate with federal and independent experts, while 

deferring application of PSD and Title V requirements to avoid creating disincentives. During 

the deferral period, the commenter would be pleased to provide additional information to 

demonstrate the reasoning for the permanent exclusion of biogenic CO2 emissions from PSD and 

Title V. The commenter also supports giving EPA time to conduct a detailed examination of the 

science, to engage with an independent scientific panel and then, if appropriate, to initiate a 

notice and comment rulemaking to implement an accounting approach.

Response: EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. Once that work is complete the Agency 

intends to undertake a rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. The commenter will have the opportunity to provide the additional 

information cited at several steps in the process including the peer review that will be conducted 

by the SAB later this year and the rulemaking mentioned above. 

Comment: Commenter 0093.1 stated that the risks to climate posed by a three-year deferral in 

order to get the science right are negligible, while the risks of seriously harming the bio-energy 

industry in its formative stages, and preventing it from delivering the greenhouse gas benefits it 

is capable of, are large.

Response: EPA thanks the commenter for the comment. 

Comment: Commenter 0084.1 urged EPA to build into the final deferral “grandfather”

language that clearly defines whether a project is “new” as of the switch-over date (i.e., the end 

of the deferral period). The commenter preferred the “commencement” of construction concept 

because it is well-developed and relatively clear.

Response: EPA will not be developing “grandfather” language in this action as this deferral is 

intended to be a temporary measure to allow the Agency time to complete its work and 
8.0 Duration of Deferral and Permitted Activities During Deferral

46

determine what, if any, the treatment of biogenic CO2 emissions should be in the PSD and Title 

V programs. This action is not the Agency’s final determination on the treatment of biogenic 

CO2 emissions in those programs. 

Comment: Commenter 0078.1 encouraged EPA to move forward with its study and rulemaking 

as soon as possible to relieve long-term uncertainties regarding Title V permitting and to 

improve biomass project viability.

Response: EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. Once that work is complete the Agency 

intends to undertake a rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. 

Comment:

a) the draft work product submitted for peer review; 

Commenter 0086.1 noted concerns with the peer review process in the RFS and 

urged EPA to engage in an open and transparent process to ensure objectivity and participation 

by the public when conducting independent panel reviews during deferral. Commenter 0086 also 

stated that EPA should allow stakeholders to nominate members of the panel, and that EPA 

should not exclude nominees purely on the grounds that they may have ties to industry. 

Commenter 0086 stated that EPA should provide a voice representing all stakeholder interests, 

should allow the public to comment on the charge questions to the panel, and should allow the 

public to provide comments to the panel itself. Commenter 0086 also stated that EPA should 

utilize Office of Management and Budget (OMB) Guidance and EPA’s Peer Review Handbook 

to ensure transparency and objectivity and that the following materials should be made available 

to the public:

b) materials and information given to the peer reviewers; 

c) the peer review report, which summarizes the peer review findings and contains 

information about the peer reviewers; 

d) logistical information about the conduct of the peer review; 

e) a memorandum, or other record, responding to the peer review comments; and 

f) the final work product. 

Response:

The SAB is an advisory body established by Congress to provide independent advice and peer 

review to EPA’s Administrator on the scientific and technical aspects of environmental issues. 

The SAB’s members are composed of experts nominated for candidacy by the public and other 

federal agencies, and selected to provide an independent scientific review of the scientific and 

technical information used or proposed as a basis for Agency regulations. The SAB operates 

through a transparent and public process as required by the Federal Advisory Committee Act. 

The SAB process follows both the EPA Peer Review Handbook and OMB’s “Final Information 

Quality Bulletin for Peer Review” (issued December 16, 2004). 

EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. EPA intends to provide its work to the 

SAB for peer review later in 2011. 
8.0 Duration of Deferral and Permitted Activities During Deferral

47

On April 27, 2011, EPA’s SAB published a notice soliciting experts for a peer review of EPA’s 

science and technical work on biogenic CO2 emissions. The commenter should contact the SAB 

directly with any questions, comments or suggestions. 

Comment: Commenters 0086.1 and 0060.1 suggested that EPA’s consideration of accounting 

methods during the scientific study should be based on science, not policy. The methodology 

should be built on the requirements of EPA IQA guidelines. Commenter 0060.1 suggested that a 

cost-benefit analysis be performed. Particularly in this case, the credibility of the models used by 

EPA depends on their transparency and ensuring the models reflect the latest knowledge about 

agricultural and food systems.

Response: EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. EPA is following all relevant guidelines 

during this process. The study and supporting documentation and analysis will be provided to 

the SAB for peer review. During the SAB peer review the public will have the opportunity to 

provide comment to the SAB of all of the information presented. 

Comment: Commenter 0104.1 suggested for categories of biomass that are less clearly longterm sources of pollution or truly carbon neutral within 1-3 years, EPA should undertake a 

scientific review of data on carbon turnover rates. The Agency does not need three years to do so 

nor is it clear that these sources should be exempted in the interim.

Response: EPA is considering the issues the commenter raises as it conducts a detailed 

examination of the science and technical issues associated with accounting for biogenic CO2

emissions. Once that work is complete the Agency intends to undertake a rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. We have 

determined that three years will be required to complete the scientific work as well as the followon rulemaking, and the commenter has not provided information to suggest otherwise. In fact, as 

explained in the preamble, it is possible that the subsequent rulemaking, depending on the nature 

of EPA’s determinations, would supersede this rulemaking and become effective in fewer than 

three years. This deferral is intended to be a temporary measure to allow the Agency time to 

complete its work and determine what, if any, the treatment of biogenic CO2 emissions should be 

in the PSD and Title V programs. This action is not the Agency’s final determination on the 

treatment of biogenic CO2 emissions in those programs. 

Comment: Commenter 0104.1 noted if EPA is going to delay regulating these biogenic carbon 

emissions considered to be de minimis, it must identify the knowledge gaps and establish that it 

can reasonably expect to fill these gaps in a timely fashion.

Response: EPA is considering the issues the commenter raises as it conducts it detailed 

examination of the science and technical issues associated with accounting for biogenic CO2

emissions. 

Comment: Commenters 0023B, 0023C, and 0117.1, noted that they look forward to working 

with the independent scientific panel and EPA to consider the technical issues of biogenic carbon 

emissions over the next three years.
8.0 Duration of Deferral and Permitted Activities During Deferral

48

Response: EPA thanks the commenters for their comments. 

Comment: One commenter (0023I) suggested the Agency may need three years because 

scientists realized that the issue of whether biomass electricity generation is carbon neutral is not 

a question of science; it’s a question of policy.

Response: This rulemaking defers the application of the PSD and Title V programs to biogenic 

CO2 emissions for a period of three years because that is the amount of time EPA has determined 

it is necessary to complete its work and the commenters have not provided information to 

suggest otherwise. In fact, as explained in the preamble, it is possible that the subsequent 

rulemaking, depending on the nature of EPA’s determinations, would supersede this rulemaking 

and become effective in fewer than three years. EPA is conducting a detailed examination of the 

science and technical issues associated with acconting for biogenic CO2 emissions. Once that 

work is complete the Agency intends to undertake a rulemaking to establish the treatment of 

these emissions in the PSD and Title V programs. Through these steps EPA will address both 

scientific and policy issues associated with biogenic CO2 emissions from stationary sources. 

Comment: Commenter 0106.1 agreed that EPA should conduct a scientific review to improve 

the understanding of the impact of bio-energy facilities on net greenhouse gas emissions and 

other environmental considerations. The scientific review should not be undertaken at the 

expense of delaying implementation. There already exist appropriate tools for wood-energy 

plants that could be considered BACT for CO2 such as certification from the Forest Stewardship 

Council (FSC). The Agency should advance the science to bring further clarity to the carbon 

accounting needed to assess the best regulatory methodology and achieve the goal of protecting 

the public health and welfare from the negative impacts of greenhouse gas pollution. However, 

this will always be an ongoing process and should not become the reason to delay 

implementation when appropriate methods are available today.

Response:

While we are considering the information the commenter cites, at this time, we do not have 

enough information or analysis to establish a permanent accounting methodology or permanent 

exemption or other treatment for biogenic CO2 emissions, even those emissions from certain 

types of feedstocks, in the PSD and Title V programs. 

 EPA is conducting a detailed examination of the science and technical issues 

associated with accounting for biogenic CO2 emissions. Once that work is complete the Agency 

intends to undertake a rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. We have determined that three years is a sufficient amount of time to 

complete that work. In fact, as explained in the preamble, it is possible that the subsequent 

rulemaking, depending on the nature of EPA’s determinations, would supersede this rulemaking 

and become effective in fewer than three years.

Comment: Commenter 0049.1 supported the proposed study of how to safeguard against 

biomass carbon pollution and to protect the ecological services that forests provide. The 

commenter also urged EPA to expand the study scope to include analysis of the forest as an 

ecosystem and the ecological services it provides. The commenter recommended the larger 

integrated study include: current role of forests in carbon sequestration and air scrubbing 

services; carbon footprint of different sources of biomass; carbon emissions of various biomass 
8.0 Duration of Deferral and Permitted Activities During Deferral

49

technologies and energy efficiencies of these technologies; appropriate scale and intensity of 

harvesting trees for biomass energy; carbon sequestration potential of forests under potential 

carbon credit policy guidelines; local economic development impacts of different biomass 

technologies; long-term cumulative impacts of the addition of biomass to the harvesting of pulp 

and other forest products upon the current forest resources and services; protection of native 

forests from conversion to biomass plantations; protection of habitat of threatened and 

endangered species and other wildlife; criteria to determine within a region and local area the 

state of forests as to age classes, rotation cycles, conversion to plantations and other non-forest 

uses, resiliency from past abuses, forest soils health, pestilence potential for native forests and 

for mono-culture plantations.

Response: EPA is considering some of the issues the commenter raises as it conducts it detailed 

examination of the science and technical issues associated with accounting for biogenic CO2

emissions. However some of the broader issues (e.g., carbon sequestration potential of forests 

under potential carbon credit policy guidelines, protection of native forests from conversion to 

biomass plantations, pestilence potential for native forests and for mono-culture plantations) are 

outside the scope of this deferral. EPA will keep in mind the commenter’s views as it conducts 

the detailed examination described above. 

Comment: Commenter 0122.1 recommended that EPA should include forestry scientists with a 

practical understanding of forests and forest practices as well as biometrics on the EPA science 

team to ensure EPA builds on proven forestry modeling protocols as it develops principles to 

evaluate the carbon benefits of biomass for energy, because building on these protocols will 

contribute to a scientifically sound understanding of the forest carbon life cycle that includes the 

entire forest system and will also aid the EPA in understanding how multiple forest products, 

processes, and conditions can be effectively considered together to understand the overall net 

carbon benefit of sustainable forestry.

Response:

On April 27, 2011, EPA’s SAB published a notice soliciting experts for a peer review of EPA’s 

science and technical work on biogenic CO2 emissions. The commenter should contact the SAB 

directly with any questions, comments or suggestions. 

 EPA is considering the issues the commenter raises as it conducts it detailed 

examination of the science and technical issues associated with accounting for biogenic CO2

emissions. EPA intends to provide its work to the SAB for peer review later in 2011. The public 

will have the opportunity to provide comments for SAB consideration.

Comment: Commenter 0122.1 suggested that EPA should include policy analysis as part of its 

scientific effort, because practical and effective policy should be simple and easy to implement 

and should avoid complex and onerous carbon accounting procedures unless it can be 

demonstrated to be scientifically necessary.

Response: EPA is considering the issues of practicality and effectiveness as it conducts a 

detailed examination of the science and technical issues associated with accounting for biogenic 

CO2 emissions. Once that work is complete the Agency intends to undertake a rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. Through these steps 

EPA will address both scientific and policy issues associated with biogenic CO2 emissions from 

stationary sources. 
8.0 Duration of Deferral and Permitted Activities During Deferral

50

8.5 Notice and Comment Rulemaking

Comment: One commenter (0023A) stated that this proposal and comment process represents 

very good government, concepts of transparency, stakeholder input and incorporation of sound 

science and policy and reflects that EPA is taking the time to get issues right and study them 

closely before making very significant decisions that may have unintended consequences. 

Commenter 0051.1 agreed that biogenic CO2 deserves further review and a separate rulemaking.

Response: EPA thanks the commenter for their comment. 
9.0 BACT During the Deferral

51

9.0 BACT During the Deferral

9.1 Disagreement that Use of Biogenic Fuels is BACT

Comment: Commenter 0101.1 stated that EPA should use the PSD program to require biomass 

projects to consider emissions controls and energy efficiency measures to reduce emissions. 

Response:

Furthermore, as discussed in the guidance, EPA does recommend that emissions controls and 

energy efficiency measures should be considered when completing a top-down BACT analysis. 

However, EPA believes that the analysis given in the guidance document is sufficient in most 

cases to support the conclusion that utilization of biomass fuels alone is BACT for a bioenergy 

facility.

 To clarify, EPA’s March 2011 Guidance for Determining Best Available Control 

Technology for Reducing Carbon Dioxide Emissions from Bioenergy Production was intended to 

apply only on an interim basis before the deferral becomes effective. EPA considers the 

commenter’s views about the appropriate controls and energy efficiency measures for biogenic 

emission sources to be beyond the scope of this action. Permitting authorities for which the 

deferral has not become effective may find the guidance useful as an interim measure to assist 

with their permitting actions. As explained in the guidance document, EPA has not provided a 

final determination of BACT for a particular source, since such determinations can only be made 

by individual permitting authorities on a case-by-case basis after consideration of the record in 

each case. Upon consideration of the record in an individual case, if a permitting authority has a 

reasoned basis to address particular issues in a different manner than EPA recommends in the 

Bioenergy BACT guidance, they have the discretion to do so. 

Comment: Commenters 0101.1 and 0132.1 contended that EPA’s March 2011 Guidance for 

Determining Best Available Control Technology for Reducing Carbon Dioxide Emissions from 

Bioenergy Production allows biomass fuel to be considered BACT for controlling biogenic CO2

emissions at energy projects. The commenter urged EPA not to adopt this approach. 

Additionally, the commenter asserted that biomass projects should be confined by the rules even 

if they deliver broad energy and environmental benefits.

Response: To clarify, EPA’s March 2011 Guidance for Determining Best Available Control 

Technology for Reducing Carbon Dioxide Emissions from Bioenergy Production was intended to 

apply only on an interim basis before the deferral becomes effective. EPA considers the 

commenter’s views about content of the guidance to be beyond the scope of this deferral action. 

Permitting authorities for which the deferral has not become effective may find the guidance 

useful as an interim measure to assist with their permitting actions. As explained in the guidance 

document, EPA has not provided a final determination of BACT for a particular source, since 

such determinations can only be made by individual permitting authorities on a case-by-case 

basis after consideration of the record in each case. Upon consideration of the record in an 

individual case, if a permitting authority has a reasoned basis to address particular issues in a 

different manner than EPA recommends in the Bioenergy BACT guidance, they have the 

discretion to do so.
9.0 BACT During the Deferral

52

Regarding the comment that biomass projects should still be confined by the rules, EPA is 

granting the deferral of biogenic CO2 emissions from stationary source permitting requirements 

because the issue of accounting for the net atmospheric impact of biogenic CO2 emissions is 

complex enough that further consideration of this important issue is warranted. During the threeyear deferral period, EPA will conduct a detailed examination of the science associated with 

biogenic CO2 emissions from stationary sources, including engaging with federal partners, 

technical experts, and an independent scientific panel to consider technical issues. Based on the 

feedback from the scientific and technical review, EPA will then undertake a rulemaking to 

determine how biogenic CO2 emissions should be treated and accounted for in PSD and Title V 

permitting. The deferral focuses on biogenic CO2 emissions from stationary sources subject to 

the PSD and Title V programs.

Comment: Commenter 0150.1 noted that the assumption that CO2 released from burning wood 

and other biomass is simply reabsorbed by new plant growth may be true for algae or very shortterm annual crops, but is incorrect for the cutting of living. This claim was supported by 

scientific evidence (see EPA-HQ-OAR-2011-0083-0150.1). In sum, commenter 0150.1 

contended that the claim that “BACT for biogenic CO2 emissions at stationary is the combustion 

of biomass fuels by itself” is simply incompatible with the basic science.

Response: EPA considers the commenter’s view about what constitutes BACT for biogenic 

CO2 emissions from stationary sources to be beyond the scope of this deferral action. EPA is 

granting the deferral of biogenic CO2 emissions from stationary source permitting requirements 

because the issue of accounting for the net atmospheric impact of biogenic CO2 emissions is 

complex enough that further consideration of this important issue is warranted. During the threeyear deferral period, EPA will conduct a detailed examination of the science associated with 

biogenic CO2 emissions from stationary sources, including engaging with federal partners, 

technical experts, and an independent scientific panel to consider technical issues. Based on the 

feedback from the scientific and technical review, EPA will then undertake a rulemaking to 

determine how biogenic CO2 emissions should be treated and accounted for in PSD and Title V 

permitting.

Comment: Commenter 0142.1 notes the choice to allow biomass energy to be considered 

BACT seems arbitrary and costly to the climate. The commenter states EPA’s awareness that 

hundreds of stand-alone biomass incineration facilities are under construction, and this decision 

will keep subsidies in place without informed guidance.

Response: EPA considers the commenter’s view about what constitutes BACT for biogenic 

CO2 emissions from stationary sources to be beyond the scope of this deferral action. To clarify, 

EPA’s March 2011 Guidance for Determining Best Available Control Technology for Reducing 

Carbon Dioxide Emissions from Bioenergy Production was intended to apply only on an interim 

basis before the deferral becomes effective. Permitting authorities for which the deferral has not 

become effective may find the guidance useful as an interim measure to assist with their 

permitting actions. As explained in the guidance document, EPA has not provided a final 

determination of BACT for a particular source, since such determinations can only be made by 

individual permitting authorities on a case-by-case basis after consideration of the record in each 

case. Upon consideration of the record in an individual case, if a permitting authority has a 
9.0 BACT During the Deferral

53

reasoned basis to address particular issues in a different manner than EPA recommends in the 

Bioenergy BACT guidance, they have the discretion to do so.

9.2 Alternative BACT Considerations Other than Carbon Neutrality

Comment: Commenter 0101.1 contended that the BACT review process could be used to 

require an analysis of the fuel source on CO2 emissions, but EPA may want to consider using the 

Additional Impact Analysis required under PSD.

Response:

Regarding the additional impacts analysis, see the Tailoring Rule preamble (75 FR 31514) for a 

full description of why we are not requiring an analysis. In short, there are currently no NAAQS 

or PSD increments established for GHG, and therefore these PSD requirements would not apply 

for GHG, even when PSD is triggered for GHG.

 Any comments concerning BACT for biogenic CO2 is beyond the scope of this 

deferral rulemaking. To clarify, EPA’s March 2011 Guidance for Determining Best Available 

Control Technology for Reducing Carbon Dioxide Emissions from Bioenergy Production was 

intended to apply only on an interim basis before the deferral becomes effective. Permitting 

authorities for which the deferral has not become effective may find the guidance useful as an 

interim measure to assist with their permitting actions. As explained in the guidance document, 

EPA has not provided a final determination of BACT for a particular source, since such 

determinations can only be made by individual permitting authorities on a case-by-case basis 

after consideration of the record in each case. Upon consideration of the record in an individual 

case, if a permitting authority has a reasoned basis to address particular issues in a different 

manner than EPA recommends in the Bioenergy BACT guidance, they have the discretion to do 

so.

Comment: Commenter 0101.1 stated that there is no need to defer applicability of the PSD 

program to biogenic emissions. Biomass projects would simply be required to consider energy 

efficiency measures and carbon capture and sequestration, as appropriate.

Response: EPA is granting the deferral of biogenic CO2 emissions from stationary source 

permitting requirements because the issue of accounting for the net atmospheric impact of 

biogenic CO2 emissions is complex enough that further consideration of this important issue is 

warranted. During the three-year deferral period, EPA will conduct a detailed examination of the 

science associated with biogenic CO2 emissions from stationary sources, including engaging 

with federal partners, technical experts, and an independent scientific panel to consider technical 

issues. Based on the feedback from the scientific and technical review, EPA will then undertake 

a rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting. The deferral focuses on biogenic CO2 emissions from stationary 

sources subject to the PSD and Title V programs.

Comment: Commenter 0101.1 noted that should EPA implement the PSD program in a way 

that recognizes the full impact of biomass combustion, the requirement to identify the most 

stringent control technology used in similar facilities and to explore technology transfer and 

innovation under BACT could be used to push biomass projects toward best-practice fuel 

procurement strategies.
9.0 BACT During the Deferral

54

Response: EPA considers the commenter’s view about what constitutes BACT for biogenic 

CO2 emissions from stationary sources to be beyond the scope of this deferral action. To clarify, 

EPA’s March 2011 Guidance for Determining Best Available Control Technology for Reducing 

Carbon Dioxide Emissions from Bioenergy Production was intended to apply only on an interim 

basis before the deferral becomes effective. Permitting authorities for which the deferral has not 

become effective may find the guidance useful as an interim measure to assist with their 

permitting actions. EPA is granting the deferral of biogenic CO2 emissions from stationary 

source permitting requirements because the issue of accounting for the net atmospheric impact of 

biogenic CO2 emissions is complex enough that further consideration of this important issue is 

warranted. During the three-year deferral period, EPA will conduct a detailed examination of the 

science associated with biogenic CO2 emissions from stationary sources, including engaging 

with federal partners, technical experts, and an independent scientific panel to consider technical 

issues. Based on the feedback from the scientific and technical review, EPA will then undertake 

a rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting. The deferral focuses on biogenic CO2 emissions from stationary 

sources subject to the PSD and Title V programs.
10.0 Facilities Permitted During Deferral

55

10.0 Facilities Permitted During Deferral

10.1 Regulatory Uncertainty

Comment: Commenter 0082.1 noted that Table 1 in the proposal gave examples, specifically 

identifying several affected entities including biomass combustion and fermentation processes. 

However, the guidance EPA issued in March 2011, which will be applicable until the deferral 

rule becomes effective, is more narrowly focused on combustion sources. This inconsistency 

places projects that would utilize biomass in fermentation processes subject to high uncertainty. 

The commenter stated that EPA should include bioenergy sources and other biogenic CO2

emissions in both the deferral rule and the subsequent rulemaking that will address exclusions for 

biogenic CO2 longer term. Commenter 0078.1 stated that EPA plans for follow-up rulemakings 

for potential step reductions in GHG applicability thresholds represent planned but unknown 

actions that hold many mills with strategic plans and decisions in suspense.

Response: The deferral rulemaking did not address or ask for comment on the guidance that is 

of concern to the commenter, thus, it is beyond the scope of this rulemaking. EPA issued interim 

guidance entitled, “Guidance for Determining Best Available Control Technology for Reducing 

Carbon Dioxide Emissions from Bioenergy Production” to help permitting authorities where the 

deferral is not effective establish a basis for concluding that under PSD programs the combustion 

of biomass fuels can be considered BACT for biogenic CO2 emissions at stationary sources, 

which is related to the treatment of biogenic CO2 emissions during the three-year deferral period. 

During this period, EPA will conduct a detailed examination of the science associated with 

biogenic CO2 emissions from stationary sources, including engaging with federal partners, 

technical experts, and an independent scientific panel to consider technical issues. Based on the 

feedback from the scientific and technical review, EPA will then undertake a rulemaking to 

determine how biogenic CO2 emissions should be treated and accounted for in PSD and Title V 

permitting. EPA understands that there is a high amount of uncertainty relating to biogenic CO2

emissions which is why we are moving forward with the deferral. The proposed deferral focuses 

on biogenic CO2 emissions from stationary sources subject to the PSD and Title V programs.

Comment: Commenter 0082.1 contended that regulating GHG will slow economic recovery 

and states that including biogenic CO2 emissions in PSD exacerbates these concerns because 

EPA’s decisions have lead to regulatory uncertainty and delay of biomass energy projects, 

further stating that such decisions ultimately will harm our nation’s forest land base by

undermining the value of working forest lands. Commenters 0082.1 and 0144.1 stated that the 

deferral as proposed provides no relief from regulatory uncertainty and predicts that projects are 

likely to continue to be delayed or abandoned while EPA continues to further study the LULUCF 

net carbon sink in the United States. Consequently, one commenter (0144.1) urges EPA to make 

a decision now that biomass used in energy applications is indefinitely excluded from CO2 -

related PSD and Title V provisions, thereby removing uncertainty. Commenter 0047.1 stated that 

regulatory uncertainty can stymie the momentum of the bioenergy industry and requested EPA 

reach an acceptable ruling as quickly as possible.

Response: EPA recognizes the concerns regarding the treatment of biomass used in energy 

applications, and is mindful of the role that biomass or biogenic fuels and feedstocks could play 

in state and local policies. However, EPA considers the commenters’ views about the economics 
10.0 Facilities Permitted During Deferral

56

of the biomass industry to be beyond the scope of this deferral action. As discussed in the 

preamble, EPA is finalizing this deferral to in order to conduct a detailed study of the science 

surrounding biogenic CO2 emissions and to develop an accounting methodology. Based on the 

feedback from the scientific and technical review, EPA will then undertake a rulemaking to 

determine how biogenic CO2 emissions should be treated and accounted for in PSD and Title V 

permitting.

EPA believes that at least some biomass feedstocks that may be utilized to produce energy have

a negligible impact on the net carbon cycle. It appears that the potential may exist for EPA to 

determine that other types of biomass feedstocks would have a negligible impact on the net 

carbon cycle impact after further detailed examination of the science associated with biogenic 

CO2 emissions. Thus, if EPA were to require all bioenergy facilities to limit emissions of CO2

before this assessment is complete, it may later determine that such actions have yielded trivial 

gain. To avoid this outcome EPA believes an initial deferral of the PSD requirements for 

bioenergy and other biogenic sources is justified at this time. However, the possibility also 

remains that more detailed examination of the science of biogenic CO2 will demonstrate that the 

utilization of some biomass feedstocks for bioenergy production will have a significant impact 

on the net carbon cycle, making application of the PSD program requirements to such emissions

necessary to fulfill Congressional intent. Therefore, EPA is finalizing a temporary, rather than a 

permanent, deferral of PSD requirements for such sources at this time in order to conduct the 

scientific study, develop and accounting methodology and take subsequent rulemaking actions to 

establish the treatment of biogenic CO2 emissions under the PSD and Title V permiting 

programs.

Comment: Commenter 0089.1 indicated the preamble language created uncertainty as to 

whether the deferral fully exempts new and modified sources permitted during the three-year

period or only delays applicability. The commenter had concerns that the temporary deferral 

could delay renewable biomass energy projects until EPA makes a permanent decision.

Response:

At this time, we are unable to predict which biogenic CO2 sources, if any, currently subject to the 

deferral would be subject to any permanent exemptions or which currently deferred sources 

would be potentially required to account for their emissions in relation to future permitting 

actions as a result of the future rulemaking EPA has committed to undertake for such purposes in 

three or fewer years, and thus, we do not have enough information at this time to consider the 

effects of allowing such grandfathering. No decision has yet been made regarding permit 

applications and permits issued after the three-year deferral period expires. 

 Stationary sources that combust biomass and construct or modify during the threeyear deferral period will avoid the application of PSD to the biogenic CO2 emissions resulting 

from those actions. Note that the deferral applies only to CO2 emissions and does not affect nonGHG pollutants or other greenhouse gases.

To the extent the deferral is not effective in a particular state at the time a PSD permit is issued, 

then the permit would need to include BACT limitations for GHG if the source emits above 

levels that make GHG subject to regulation under applicable rules. Some states may not have 

any, or may have only a few, sources that combust biomass, and may have adequate information 

and resources as to the nature of biogenic emissions from those sources. To further reduce 
10.0 Facilities Permitted During Deferral

57

uncertainty, EPA issued interim guidance entitled, “Guidance for Determining Best Available 

Control Technology for Reducing Carbon Dioxide Emissions from Bioenergy Production” that is 

applicable for permitting authorities where the deferral is not effective, and various methods are 

available to calculate both the biogenic and fossil portions of CO2 emissions, including those 

methods contained in the GHG Reporting Program (40 CFR part 98).

Comment: Commenter 0078.1 stated that if EPA fails to finalize a permanent solution for 

biomass emissions after the three-year deferral period, biogenic CO2 would automatically be 

included in PSD and Title V permitting, and EPA must avoid the uncertainty that automatic 

default would cause and provide an orderly determination and path for treatment of biogenic 

emissions that does not penalize projects.

Response:

Based on the feedback from the scientific and technical review, EPA will then undertake a 

rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting. This will reduce uncertainty for permitting authorities and sources 

preparing applications and permits with potential biogenic CO2 emissions.

 At this time, we are unable to predict which biogenic CO2 sources, if any, currently 

subject to the deferral would be subject to any permanent exemptions or which currently deferred 

sources would be potentially required to account for their emissions in relation to future 

permitting actions as a result of the future rulemaking EPA has committed to undertake for such 

purposes in three or fewer years. Thus, we do not have enough information at this time to 

consider the effects of allowing such grandfathering. No decision has yet been made regarding 

permit applications and permits issued after the three-year deferral period expires. EPA is 

committed to conducting a detailed examination of the science associated with biogenic CO2

emissions from stationary sources, including engaging with federal partners, technical experts, 

and an independent scientific panel to consider technical issues all within the three-year deferral 

period, thus preventing an ‘automatic default.’ Recently, EPA’s SAB published a notice 

soliciting experts for a peer review of EPA’s science and technical research on biogenic CO2

emissions. EPA intends to provide their study that examines the science and technical associated 

with biogenic CO2 emissions from stationary source and accompanying accounting framework to 

the SAB for peer review later in 2011. 

Comment: Commenter 0144.1 recognized that burning whole trees for fuel likely warrants 

demonstration that the biomass combustion emissions are offset with life cycle demonstrated regrowth from an academic perspective. Yet, Minnesota forests are in a net re-growth situation that 

is a backdrop for individual land owner choices for harvesting and re-growing trees. Placing a 

hold on biomass exclusion for the sake of documenting whole tree energy life cycle assessment 

can have the unintended consequence of creating uncertainty for all biomass energy production 

in a situation where use of whole trees for energy production is not currently or expected to be a 

significant practice in Minnesota.

Response: EPA believes that at least some biomass feedstocks that may be utilized to produce 

energy have a negligible impact on the net carbon cycle, and it appears that the potential may 

exist for other types of biomass feedstocks to have a negligible impact on the net carbon cycle 

impact. Yet the possibility also remains that the utilization of some biomass feedstocks for 

bioenergy production will have a significant impact on the net carbon cycle, making application 
10.0 Facilities Permitted During Deferral

58

of the PSD program requirements to such emissions necessary to fulfill Congressional intent.

Therefore, EPA is committed to a detailed examination of the science associated with biogenic 

CO2 emissions from stationary sources, including engaging with federal partners, technical 

experts, and an independent scientific panel to consider technical issues. Based on the feedback 

from the scientific and technical review, EPA will then undertake a rulemaking to determine how 

biogenic CO2 emissions should be treated and accounted for in PSD and Title V permitting.

To the extent the deferral is not effective in a particular state at the time a PSD permit is issued, 

then the permit would need to include BACT limitations for GHG if the source emits above 

levels that make GHG subject to regulation under applicable rules. Some States may not have 

any, or may have only a few, sources that combust biomass, and may have adequate information 

and resources as to the nature of biogenic emissions from those sources. To further reduce 

uncertainty, EPA issued interim guidance for permitting authorities for which the deferral has not 

become effective entitled, “Guidance for Determining Best Available Control Technology for 

Reducing Carbon Dioxide Emissions from Bioenergy Production” and various methods are 

available to calculate both the biogenic and fossil portions of CO2 emissions, including those 

methods contained in the GHG Reporting Program (40 CFR part 98).

Comment: Commenters 0013.1, 0046, 0056.1, 0071.1, and 0090.1 expressed concern that the 

regulation of biomass will spring back into effect after three years if EPA does not finalize a 

further rule. This kind of sunset treatment will create significant uncertainty throughout the 

three-year period. No one can predict what events might delay EPA’s consideration of this issue 

and ultimate revision of the Tailoring Rule. The commenter urged the Agency to take a more 

flexible approach, such as removing the sunset provision and maintaining the position that EPA 

should not regulate biomass emissions unless it adopts a rule to do so after notice and comment. 

Response:

EPA believes it has the authority to exclude biogenic CO2 emissions from the PSD and Title V 

requirements for the three-year deferral period and will be exploring whether a permanent 

exemption is permissible for at least some and perhaps all types of feedstocks. As discussed in 

the preamble, EPA believes that at least some biomass feedstocks that may be utilized to produce 

energy have a negligible impact on the net carbon cycle and it appears, after further examination 

of the science, that the potential may exist for EPA to determine that other types of biomass 

feedstocks would also have a negligible impact as well. If EPA were to require all bioenergy

facilities to limit emissions of CO2 before this assessment is complete, it may later determine that 

 The purpose of the three-year deferral is to better understand the impacts of biogenic 

CO2 emissions. The EPA is committed to an expeditious schedule – during the three year 

deferral period, EPA will conduct a detailed examination of the science associated with biogenic 

CO2 emissions from stationary sources, including engaging with federal partners, technical 

experts, and an independent scientific panel to consider technical issues. Recently, EPA’s SAB

published a notice soliciting experts for a peer review of EPA’s science and technical work on 

biogenic CO2 emissions. EPA intends to provide their study that examines the science and 

technical associated with biogenic CO2 emissions from stationary source and accompanying 

accounting framework to the SAB for peer review later in 2011. Based on the feedback from the 

scientific and technical review, EPA will then undertake a rulemaking to determine how biogenic 

CO2 emissions should be treated and accounted for in PSD and Title V permitting. The Agency 

does not foresee any delays in our reconsideration at this time.
10.0 Facilities Permitted During Deferral

59

such actions have yielded trivial gain. To avoid this outcome EPA believes an initial deferral of 

the PSD requirements for bioenergy and other biogenic sources is justified at this time. However, 

the possibility also remains that more detailed examination of the science of biogenic CO2 will

demonstrate that the utilization of some biomass feedstocks for bioenergy production will have a 

significant impact on the net carbon cycle, making application of the PSD program requirements 

to such emissions necessary to fulfill Congressional intent. Thus, EPA is proposing only a

temporary, rather than a permanent, deferral of PSD requirements for such sources at this time.

Comment: Commenters (0121.1 and 0120.1) are concerned about the consequences that 

regulatory uncertainty could create for the biomass market and thus encourage EPA to declare 

biomass exempt from GHG regulation until it adopts rules. The commenter requested a speedy 

exemption as to avoid a protracted period of market uncertainty, which would ultimately be 

detrimental to landowners as well as source lands. 

Response:

The Agency is proceeding as expeditiously as possible, ensuring that a detailed examination of 

the science associated with biogenic CO2 emissions from stationary sources is conducted, 

including engaging with federal partners, technical experts, and an independent scientific panel 

to consider technical issues. Stationary sources that combust biomass and construct or modify 

during the three-year deferral period will avoid the application of PSD to the biogenic CO2

emissions resulting from those actions. Note that the deferral applies only to CO2 emissions and 

does not affect non-GHG pollutants or other greenhouse gases.

 EPA recognizes the concerns regarding the treatment of biomass used in energy 

applications, and is mindful of the role that biomass or biogenic fuels and feedstocks could play 

in state and local policies. EPA considers the commenters’ views on the economics of the 

biomass industry to be beyond the scope of this deferral action. The information gathered from 

stakeholders in response to the CFI provided diverse perspectives on treatment of biogenic CO2

emissions in pre-construction and operating permit reviews, and therefore, further study is

warranted. 

At this time, we are unable to predict which biogenic CO2 sources, if any, currently subject to the 

deferral would be subject to any permanent exemptions or which currently deferred sources 

would be potentially required to account for their emissions in relation to future permitting 

actions as a result of the future rulemaking EPA has committed to undertake for such purposes in 

three or fewer years, and thus, we do not have enough information at this time to consider the 

effects of allowing such grandfathering. No decision has yet been made regarding permit 

applications and permits issued after the three-year deferral period expires. 

To the extent the deferral is not effective in a particular state at the time a PSD permit is issued, 

then the permit would need to include BACT limitations for GHG if the source emits above 

levels that make GHG subject to regulation under applicable rules. Some States may not have 

any, or may have only a few, sources that combust biomass, and may have adequate information 

and resources as to the nature of biogenic emissions from those sources. To further reduce 

uncertainty, EPA issued interim guidance for permitting authorities for which the deferral has not 

become effective entitled, “Guidance for Determining Best Available Control Technology for 

Reducing Carbon Dioxide Emissions from Bioenergy Production” and various methods are 
10.0 Facilities Permitted During Deferral

60

available to calculate both the biogenic and fossil portions of CO2 emissions, including those 

methods contained in the GHG Reporting Program (40 CFR part 98).

Comment: Four commenters (0064.1, 0090.1, 0111.1, and 0120.1) stated that imposition of the 

Tailoring Rule and PSD permitting requirements would delay and potentially jeopardize planned 

projects that have beneficial effects. Commenter 0064.1 listed benefits such as air quality 

improvements, reduction of fossil fuel consumption, long term provision of renewable 

electricity, and retention and potential creation of jobs. 

Response:

Based on the feedback from the scientific and technical review, EPA will then undertake a 

rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting. As discussed in the preamble, EPA believes that at least some 

biomass feedstocks that may be utilized to produce energy have a negligible impact on the net 

carbon cycle, and it appears that the potential may exist for EPA to determine that other types of

biomass feedstocks also would have a negligible impact. However, the possibility also remains

that more detailed examination of the science of biogenic CO2 will demonstrate that the 

utilization of some biomass feedstocks for bioenergy production will have a significant impact 

on the net carbon cycle, making application of the PSD program requirements to such emissions

necessary to fulfill Congressional intent. Thus, EPA is proposing only a temporary, rather than a 

permanent, deferral of PSD requirements for such sources at this time.

 EPA recognizes the concerns regarding the treatment of biomass and is mindful of 

the role that biomass or biogenic fuels and feedstocks could play in state and local policies. EPA 

considers the commenters’ views about the economics of the biomass industry to be beyond the 

scope of this deferral action. Information gathered from stakeholders in response to the CFI 

provided diverse perspectives on treatment of biogenic CO2 emissions in pre-construction and 

operating permit reviews, which indicates further study is warranted. The Agency is proceeding 

as expeditiously as possible, ensuring that a detailed examination of the science associated with 

biogenic CO2 emissions from stationary sources is conducted. The Agency is committed to 

working with stakeholders to examine appropriate ways to treat biogenic CO2 emissions.

10.2 Permitting Decisions Made During Deferral Should Hold

Comment: Commenters 0078.1, 0082.1, 0083.1 and 0140.1 and stated that complete and 

approved PSD permit applications and non-PSD projects initiated during the period the deferral 

rule is in effect must be honored after the deferral period ends. Commenter 0089.1 had concerns 

that PSD requirements could be applied retroactively after the three-year deferral, and suggested 

that EPA clarify the impacts on sources permitted, constructed, or modified in the three-year

period.

Response: Major stationary sources of biogenic CO2 emissions that are constructed or modified 

where the deferral is effective will avoid the application of PSD to the biogenic CO2 emissions 

resulting from those actions. At this time, we are unable to predict which biogenic CO2 sources, 

if any, currently subject to the deferral would be subject to any permanent exemptions or which 

currently deferred sources would be potentially required to account for their emissions in relation 

to future permitting actions as a result of the future rulemaking EPA has committed to undertake 

for such purposes in three or fewer years. Note that the deferral applies only to CO2 emissions 
10.0 Facilities Permitted During Deferral

61

and does not affect non-GHG pollutants or other greenhouse gases. Sources issued complete and 

approved permits during the deferral period would continue their projects accordingly. 

No decision has yet been made regarding permit applications and permits issued after the threeyear deferral period expires. During the deferral, EPA will conduct a detailed examination of the 

science associated with biogenic CO2 emissions from stationary sources, including engaging 

with federal partners, technical experts, and an independent scientific panel to consider technical 

issues. Based on the feedback from the scientific and technical review, EPA will then undertake 

a rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting.

Comment: Commenters 0084.1 and 0089.1 urged EPA to build into the final deferral 

“grandfather” language that clearly defines whether a project is “new” as of the switch-over date 

(end of deferral period). Commenter 0084.1 preferred the “commencement” of construction 

concept because it is well-developed and relatively clear.

Response:

No decision has yet been made regarding permit applications and permits issued after the threeyear deferral period expires. During the deferral, EPA will conduct a detailed examination of the 

science associated with biogenic CO2 emissions from stationary sources, including engaging 

with federal partners, technical experts, and an independent scientific panel to consider technical 

issues. Based on the feedback from the scientific and technical review, EPA will then undertake 

a rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting.

 EPA will not be developing “grandfather” language as this rule is a deferral for the 

purposes of better understanding the impacts of biogenic CO2 emissions. Major stationary 

sources of biogenic CO2 emissions that are constructed or modified where the deferral is 

effective will avoid the application of PSD to the biogenic CO2 emissions resulting from those 

actions. Note that the deferral applies only to CO2 emissions and does not affect non-GHG

pollutants or other greenhouse gases. Sources issued complete and approved permits during the 

deferral period would continue their projects accordingly.

Comment:

Response: Stationary sources of biogenic CO2 emissions that are constructed or modified where 

the deferral is effective will avoid the application of PSD to the biogenic CO2 emissions resulting 

from those actions. Note that the deferral applies only to CO2 emissions and does not affect nonGHG pollutants or other greenhouse gases. Sources issued complete and approved permits 

during the deferral period would continue their projects accordingly. 

Commenter 0056.1 asked that EPA clarify use of the word “defer” in regard to the 

accounting of emissions, rather than using the word “exempt.” This implies the possibility that 

permitting actions during this three-year window may be forced into a retroactive review once 

EPA establishes the biogenic life-cycle factors. The risk of a retroactive review of projects 

undertaken during the three-year window would significantly inhibit alternative energy projects 

due to a lack of regulatory certainty and the resulting economic impact. The commenter strongly 

recommends that EPA provide clarification in the final rule that permitting actions undertaken in 

the three to five year window will not be retroactively examined.
10.0 Facilities Permitted During Deferral

62

No decision has yet been made regarding permit applications and permits issued after the threeyear deferral period expires. During the deferral, EPA will conduct a detailed examination of the 

science associated with biogenic CO2 emissions from stationary sources, including engaging 

with federal partners, technical experts, and an independent scientific panel to consider technical 

issues. Based on the feedback from the scientific and technical review, EPA will then undertake 

a rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting.

10.3 Permits Issued During Deferral Should Not be Grandfathered

Comment: Several commenters (0023H, 0023I, 0166, 0101.1 0137.1, and 0142.1) were 

concerned that biogenic sources permitted during the deferral period would be permanently 

exempt from BACT requirements for CO2, and that such an exemption could have climate 

change implications outlasting the deferral period even if EPA concludes after the scientific 

study that biogenic CO2 should not be exempt from BACT requirements. Commenter 0166 is 

also concerned that the deferral will provide an incentive for industry to obtain a large number of 

permits for biogenic sources that will be grandfathered from PSD requirements creating de facto 

sacrifice zones in rural, working class, and minority communities. Commenter 0048.1 stated that 

grandfathering of existing facilities under less stringent rules should not be allowed, as this sets a 

bad precedent.

Response: EPA will not be developing “grandfather” language as this rule is a deferral for the 

purposes of better understanding the impacts of biogenic CO2 emissions. Major stationary

sources of biogenic CO2 emissions that are constructed or modified where the deferral is 

effective will avoid the application of PSD to the biogenic CO2 emissions resulting from those 

actions. Note that the deferral applies only to CO2 emissions and does not affect non-GHG

pollutants or other greenhouse gases.

At this time, we are unable to predict which biogenic CO2 sources, if any, currently subject to the 

deferral would be subject to any permanent exemptions or which currently deferred sources 

would be potentially required to account for their emissions in relation to future permitting 

actions as a result of the future rulemaking EPA has committed to undertake for such purposes in 

three or fewer years, and thus, we do not have enough information at this time to consider the 

effects of allowing such grandfathering. No decision has yet been made regarding permit 

applications and permits issued after the three-year deferral period expires. During the threeyear deferral period, EPA will conduct a detailed examination of the science associated with 

biogenic CO2 emissions from stationary sources, including engaging with federal partners, 

technical experts, and an independent scientific panel to consider technical issues. Based on the 

feedback from the scientific and technical review, EPA will then undertake a rulemaking to 

determine how biogenic CO2 emissions should be treated and accounted for in PSD and Title V 

permitting.

10.4 EPA Should Issue a Moratorium on Major Biogenic Projects During 

Deferral

Comment: Commenters 0023H, 0023I, 0048.1, 0049.1, 0110, 0118.1, 0119.1, 0138.1 0142.1, 

0143.1, 0148, 0166, 0216, and 0269 stated that EPA should initiate a moratorium on construction 
10.0 Facilities Permitted During Deferral

63

of sources of biogenic CO2 until the scientific studies are complete. Commenter 0023I also 

presented the alternative that EPA should make it clear that any plant built during the deferral 

will be subject to the new rules developed based on the scientific study, and commenters 0048.1 

and 0166 further stated that there should be no expansion of existing facilities during the 

deferral.

Commenter 0118.1 communicated that this would protect the environment and the public 

interest, allow time for EPA to consider the science and unique characteristics of various 

feedstocks, and avoid administrative burdens related to permitting at both state and federal 

levels. Furthermore, the commenter noted that the “potential to emit” phrase in 40 CFR 51.166 

and 40 CFR 70.2 provides the administrative means to differentiate between facilities which 

clearly are not subject to regulation, and those which have a “potential to emit” at or above the

threshold levels.

Commenter 0119.1 declared that without a moratorium facilities will be permitted or modified at 

the expense of our forests, climate, and local communities without consideration of what the 

implications may be for forests. The commenter noted that a regulatory holiday can only increase 

the already‐frenzied rate of development of the bioenergy industry at the time when calm and 

careful consideration of science and policy options is needed. The commenter further contended 

that the effect of the three year deferral could actually be much longer because once permitted, 

PSD regulations would not apply until facilities undertook a major modification.

Response: EPA recognizes the concerns regarding the treatment of biomass and potential 

impacts to environment and health. The Agency is proceeding as expeditiously as possible, 

ensuring that a detailed examination of the science associated with biogenic CO2 emissions from 

stationary sources is conducted, including engaging with federal partners, technical experts, and 

an independent scientific panel to consider technical issues. Based on the feedback from the 

scientific and technical review, EPA will then undertake a rulemaking to determine how biogenic 

CO2 emissions should be treated and accounted for in PSD and Title V permitting.

In some cases, the use of biological material as a fuel would clearly reduce net atmospheric CO2

levels. In these cases, requiring permitting at this time, before conducting the detailed scientific

examination that is required to develop an appropriate accounting system for bioenergy and other 

biogenic sources, might actually discourage projects that would have a net benefit for the

atmosphere. However, the possibility also remains that more detailed examination of the science 

of biogenic CO2 will demonstrate that the utilization of some biomass feedstocks for bioenergy

production will have a significant impact on the net carbon cycle, making application of the PSD 

program requirements to such emissions necessary to fulfill Congressional intent. Thus, EPA is 

proposing only a temporary, rather than a permanent, deferral of PSD requirements for such

sources at this time.

Comment: Commenter 0142.1 asks whether EPA considered the following questions: 

1. The cumulative impact to our forests from new construction of facilities that will almost 

certainly occur due to the EPA’s decision to defer this permitting for three years?

2. The cumulative effect on our nation’s air quality from new construction of facilities that 

will almost certainly occur due to the EPA’s decision to defer this permitting for three 

years? Impacts and costs from asthma and other respiratory diseases, etc.?
10.0 Facilities Permitted During Deferral

64

3. The impact to recycling programs and infrastructure by allowing virgin forest fiber kraft 

pulp mills to perpetuate the myth of carbon-neutrality of these emissions from the high 

volumes of burning of black liquor, hogged fuel and other biomass? Or competition for 

municipal solid waste, especially paper, by allowing incinerators this loophole and that 

will almost certainly occur due to the EPA’s decision to defer this permitting for three 

years? These two factors hurt recycling and recycled product manufacturing significantly 

and are unfair. A decision to defer, which will create winners and losers, and makes these 

other industries the losers, is arbitrary. And incidentally, also contrary to EPA’s long 

established scientifically driven goals in waste management and support for recycling.

Response: The purpose of the three-year deferral is to weigh a variety of factors, such as those 

listed by the commenter above. Multiple factors need to be considered to accurately assess the 

net atmospheric impacts of the use of a particular type of fuel by a stationary source over a

specified time period, that extends into the future: Net emissions to the atmosphere (emissions 

from the facility and sequestration elsewhere) of carbon from the biomass used for bioenergy; 

the time scale against which net emissions should be measured; delineation of geographic areas 

for measurement; and leakage.

EPA recognizes the concerns regarding the treatment of biomass and potential environmental 

and health impacts, and is mindful of the role that biomass or biogenic fuels and feedstocks 

could play in state and local policies. The Agency is allowing sufficient time to consider the 

unique characteristics and attributes of biogenic CO2 feedstocks and is committed to working 

with stakeholders to examine appropriate ways to treat biomass combustion emissions. EPA is 

proceeding as expeditiously as possible, ensuring that a detailed examination of the science 

associated with biogenic CO2 emissions from stationary sources is conducted, including 

engaging with federal partners, technical experts, and an independent scientific panel to consider 

technical issues. Based on the feedback from the scientific and technical review, EPA will then 

undertake a rulemaking to determine how biogenic CO2 emissions should be treated and 

accounted for in PSD and Title V permitting.
11.0 Rationale and Legal Justification for Interim Deferral

65

11.0 Rationale and Legal Justification for Interim Deferral

Comment: Commenter 0042.1 declared that in the Tailoring Rule EPA dictated which 

stationary sources of greenhouse gases would have to obtain permits and meet other 

requirements under PSD and Title V and which would not. Specifically, the commenter noted, 

the proposed rule directed that EPA’s Inventory of U.S. Greenhouse Gas Emissions and Sinks 

should be used “to calculate a source’s GHG emissions.” Commenter 0042.1 further pointed out 

that the inventory does not count carbon dioxide emissions from combustion of biomass at 

stationary sources; rather, it assumes these sources are carbon neutral. Due to the inventory and 

because EPA provided no further explanation in the preamble to the proposed regulations or 

elsewhere, the commenter always presumed that EPA did not propose to deviate from this policy 

in PSD and Title V. The commenter expressed shock when the final Tailoring Rule provided 

that carbon dioxide emissions from biomass combustion would count toward the rule’s 

applicability thresholds for the PSD and Title V. Commenter 0042.1 noted that no one had ever 

asked EPA to exempt biogenic emissions from the Tailoring Rule; rather commenters had asked 

EPA to maintain the policy separating biogenic emissions from fossil fuel emissions.

Response: The deferral rulemaking did not address or ask for comment on the Final Tailoring 

Rule which is of concern to the commenter, thus, it is beyond the scope of this rulemaking. The 

proposal was solely focused on biogenic CO2 emissions from stationary sources subject to the 

PSD and Title V programs, which is related to the treatment of biogenic CO2 emissions during 

the three-year deferral period. During this period, EPA will conduct a detailed examination of the 

science associated with biogenic CO2 emissions from stationary sources, including engaging 

with federal partners, technical experts, and an independent scientific panel to consider technical 

issues. Based on the feedback from the scientific and technical review, EPA will then undertake 

a rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting. 

11.1 Applicability of Major Permitting Programs to Biogenic CO2

Comment: Commenter 0087.1 stated that EPA was justified in granting the NAFO petition for 

reconsideration, because there are many important issues about application of CAA programs to 

biogenic emissions which were not considered prior to EPA’s promulgation of the Tailoring 

Rule and because the final rule presented new issues not included in the proposal by applying 

permitting requirements to biogenic emissions. The commenter stated that the final rule 

justification failed to respond to some comments about treatment of biogenic emissions provided 

by stakeholders in response to the proposal and the justification presented arguments in response 

to other biogenic comments for the first time in the final rule. The commenter stated that 

stakeholders did not consider the proposed Tailoring Rule to apply to biogenic CO2 emissions

because EPA referenced standard methodologies (for calculating GHG emissions from stationary 

sources) that do not include biogenic emissions in both the endangerment finding and the 

Tailoring Rule proposal and because EPA’s previous regulations concerning CO2 emissions 

reporting did not include CO2 emissions from biogenic fuels, consistent with IPCC protocols that 

excluded biogenic CO2 emissions. The commenter understood the proposed Tailoring Rule to 

consistently incorporate the carbon neutrality of biogenic CO2 that EPA (and the U.S. 

Department of Energy [DOE]) had consistently used in all previous rules and guidelines, because

the proposed rule stated that sources should rely on EPA’s Inventory of U.S. Greenhouse Gas 
11.0 Rationale and Legal Justification for Interim Deferral

66

Emissions and Sinks for guidance on how to calculate a source’s GHG emissions. The 

commenter stated that industry stakeholders and others supported the proposed Tailor Rule’s 

approach and commented extensively on the problems that would result if EPA applied the 

permitting programs to biogenic emissions and urged EPA to explicitly exclude biogenic CO2

emissions in the final Tailoring Rule. The commenter stated that stakeholders never had an 

opportunity to address EPA’s justification for including biogenic CO2 emissions in the final 

Tailoring Rule and found inadequacies in the final rule’s responses to stakeholder comments. 

The commenter stated that because EPA did not propose to apply the PSD and Title V programs 

to biogenic emissions, and because many new issues about biogenic emissions were raised in 

EPA’s response to comments for the final Tailoring Rule, the petition for reconsideration raised 

objections to the final rule that arose after the public comment period, meeting the criteria for a 

petition for reconsideration under CAA Section 307(d)(7).

Response: Based on careful consideration of the petitioners' arguments, together with the 

weight of the comments received on the CFI, EPA concluded that the issue of accounting for the 

net atmospheric impact of biogenic CO2 emissions is complex enough that further consideration 

of this important issue is warranted. Therefore, EPA granted the petition for reconsideration on 

January 12, 2011. Regarding commenters' claims that the Inventory excludes CO2 emissions 

from biomass, the Inventory does not exclude these emissions. Rather, they are included in the 

LULUCF Sector rather than the Energy Sector to avoid double-counting at the national scale. 

The narrow reference to the use of the Inventory's GWP values for estimating GHG emissions 

was provided to offer consistent guidance on how to calculate these emissions and not as an 

indication, direct or implied, that biomass emissions would be excluded from permitting 

applicability merely by association with the national inventory (see 74 FR 55351, under the 

definition for “carbon dioxide equivalent”). EPA also notes that commenters did, in fact, have 

the opportunity to comment on the treatment of biogenic emissions during the Tailoring Rule 

process, and EPA received a number of comments in this regard. These comments were 

addressed in the final Tailoring Rule, where EPA also noted that the Agency had not yet

evaluated the permitting burdens associated with biogenic CO2 emissions, and had not received 

comments indicating that an overwhelming burden justified exclusion at that time. 75 FR

31,514, 31,591. There, we also indicated our intent to solicit additional comments, and perform 

the further investigation necessary to determine how to best treat biogenic CO2 emissions. Id. 

This action fulfills that intent, and enables the Agency to make its final decision on the treatment 

of these emissions based on a thorough analysis of applicable science and policy concerns.

Comment: Comments were received both supporting and opposing the deferral based on 

applicability criteria under PSD and Title V. One State permitting authority commenter (0102.1) 

was concerned that without the deferral many ethanol, biodiesel, and wastewater treatment plants 

would be affected by the PSD and Part 70 rules. One commenter (0095.1) supported deferral, but 

cited 40 CFR 51.166(a)(6)(i),(iii) as bases for asserting that states with federally approved PSD 

programs are not required to revise PSD applicability criteria until three years after promulgation 

of the Tailoring Rule. Several commenters (0063.1, 0086.1, 0087.1, and 0091.1) used biogenic 

carbon neutrality arguments to state that such emissions are properly excluded from major source 

threshold determinations. Commenters (0063.1, 0086.1, and 0091.1) suggested that absence of 

land use emissions or discussions of biogenic emissions in the endangerment finding requires 

exclusion, because the endangerment finding is the source of CAA authority for GHG 
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67

regulations. Commenter 0091.1 stated that the source of the generation of biogenic CO2 should 

not be used as a factor to determine if it should be regulated, but that examples exist where EPA

has determined that biogenic CO2 is carbon neutral (e.g., landfill gases). Therefore, placing 

biogenic CO2 under the regulatory umbrella of PSD and Title V will create an undue burden on 

the regulated community as well as the regulating agencies. Similarly, commenter 0087.1 stated 

that EPA should revise its definition of GHG to exclude biogenic CO2 to avoid imposing 

permitting and BACT requirements on biogenic sources. 

Response: EPA appreciates commenters who expressed support for the deferral based on the 

applicability criteria under PSD and tile V permitting programs and notes EPA will be evaluating 

the carbon neutrality arguments in greater detail as part of its development of accounting 

methodologies. These comments underscore the complexity of issues associated with biogenic 

emissions of CO2 and their role in the carbon cycle. As discussed in the preamble, EPA is using 

the time under this interim deferral to study the science surrounding biogenic CO2 emissions and 

is developing an accounting framework to assist permitting programs and sources. This interim 

deferral represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis sources of air pollution. EPA will consider the information about the 

carbon lifecycle presented by these commenters, as well as others, as it conducts this study and 

develops the accounting framework prior to developing subsequent regulations establishing 

treatment for biogenic emissions under the PSD and Title V programs. Subsequent regulations 

to establish treatment of specific sources of biogenic emissions under the PSD and Title V 

programs, based on the results of the study and development of the accounting framework, are 

beyond the scope of this action.

Comment: Commenter 0104.1 opposed the deferral and did not feel that EPA had justified the 

special treatment of biogenic CO2 discussed in the proposal, because a PSD netting approach that 

counts off-site, un-enforceable activities that may occur in the future (i.e., biomass re-growth) as 

equivalent to a source’s direct emissions would be a significant departure from EPA’s historic 

approach to PSD applicability, and such an approach would undermine the effectiveness of the 

Act as the best method for setting targets for GHG reductions in the absence of further 

Congressional action on climate change. Similarly, Commenter 0115.1 stated that nothing in the 

statute allows the EPA to create an exemption from PSD and Title V programs based on the fuel 

supply or type of source that emits the pollutant. The commenter argued that exempting biogenic 

CO2 emissions during the deferral violates the CAA by permitting biomass facilities without 

requiring a demonstration that the sources will meet the BACT requirement for greenhouse 

gases.

Response: EPA disagrees with the commenters’ characterization of the action being taken in 

this rulemaking. As explained in the preamble, EPA believes that based on information currently 

before the Agency, including information provided in response to the CFI and the proposal for 

this rule, that emissions from certain biomass feedstocks may be carbon neutral or de minimis but 

also believes based on the complexity of this evidence that the deferral to allow for further study 

is warranted. EPA is using the time under this interim deferral to study the science surrounding 

biogenic CO2 emissions and is developing an accounting framework to assist permitting 
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68

programs and sources. This interim deferral represents a permissible application of wellestablished administrative law doctrines, necessitated by the scientific uncertainty surrounding 

the accounting of biogenic CO2 emissions, to develop a regulatory scheme that implements the 

CAA consistent with Congressional intent in a step-wise fashion designed to minimize 

administrative burdens and avoid unnecessary regulation of de minimis amounts of air pollution. 

EPA will consider the information about the carbon lifecycle presented by the commenter, as 

well as others, as it conducts this study and develops the accounting framework prior to 

developing subsequent regulations. Subsequent regulations to establish treatment of specific 

sources of biogenic emissions under the PSD and Title V programs, based on the results of the 

study and development of the accounting framework, are beyond the scope of this action.

Comment: Commenter 0350.1 stated that EPA’s proposal to redefine “subject to regulation” to 

exclude biogenic CO2 is not supported. The commenter noted that in the Tailoring Rule, EPA 

re-defined “subject to regulation” to temporarily increase the statutory threshold for all 

greenhouse gas emissions; now, EPA proposes to revise the term by splitting the regulated 

pollutant while admitting that biogenic CO2 molecules have the same GWP in the atmosphere as 

fossil CO2 molecules. The commenter asserted that there can be no doubt that CO2 indeed is now 

“subject to regulation.” The commenter stated that in the Tailoring Rule, the Agency determined 

that it had no basis for exempting biogenic CO2 emissions from the permitting requirements on 

the “administrative necessity,” and “absurd results” doctrines and that conclusion remains 

correct. The commenter stated that the proposal either changes or contradicts the Tailoring Rule. 

The commenter pointed out that the air pollutant is CO2, not “fossil-fuel-based CO2,” and under 

any reading of the term “subject to regulation under the Act,” CO2 is now subject to permitting. 

The commenter stated that EPA’s deferral proposal is not the result of analysis or interpretation 

of the terms “air pollutant” and “subject to regulation” in Sections 165(a)(4) and 169(3), or of 

any other statutory language anywhere else in the CAA, or an examination of Congressional 

intent. The commenter noted that EPA does not devote a single sentence to trying to justify its 

rulemaking based on such an inquiry, but instead, EPA seeks to justify its actions solely based on 

the doctrines of “de minimis,” “administrative necessity,” and “absurd results.”

Response: EPA disagrees with the commenters’ characterization of the action being taken in 

this rulemaking. Courts have consistently held that administrative agencies have inherent 

authority to reconsider their decisions and change previously issued regulations. In Chevron v. 

NRDC, the Supreme Court noted that “[a]n initial agency interpretation is not instantly carved in 

stone,” rather, the agency “must consider varying interpretations and the wisdom of its policy on 

a continuing basis.” 467 U.S. 863-864 (1984). As explained in the preamble, EPA believes that 

based on information currently before the Agency, including information provided in response to 

the CFI and the proposal for this rule, that emissions from certain biomass feedstocks may be 

carbon neutral or de minimis but also believes based on the complexity of this evidence that the 

deferral to allow for further study is warranted. EPA is using the time under this interim deferral 

to study the science surrounding biogenic CO2 emissions and is developing an accounting 

framework to assist permitting programs and sources. This interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis amounts of air pollution. Subsequent regulations to establish treatment of specific 
11.0 Rationale and Legal Justification for Interim Deferral

69

sources of biogenic emissions under the PSD and Title V programs, based on the results of the 

study and development of the accounting framework, are beyond the scope of this action.

Comment: Commenter 0350.1 stated that EPA’s proposed blanket exemption will thwart the 

purpose and design of the CAA permitting requirements. The commenter stated that deferring 

permitting for biogenic CO2 emissions cannot be reconciled with the purposes of the PSD 

program under Section 160 of the Act, because even a temporary deferral from permitting 

requirements would increase incentives for uncontrolled biomass development and significantly 

increase near-term CO2 emissions. The commenter stated that the deferral does not protect 

health or welfare, preserve air quality, insure growth will be consistent with preservation of air 

resources, or promote careful decision making and informed public participation. The 

commenter indicated EPA’s proposed approach undermines the fundamental policy choices that 

Congress made in adopting the PSD program: (1) that it is preferable to prevent air pollution 

from becoming a problem in the first place; and (2) that controls should be installed when new 

sources are being constructed rather than as retrofits on existing sources.

The commenter stated that waiving the applicable permitting requirements on the basis that 

further study might determine that there could be CO2 emission benefits, demonstrably 

undermines the “prevention” purpose of the PSD program and the policy choices made by 

Congress. The commenter indicated it is simply not reasonable to believe that Congress could 

have intended EPA to adopt a stance of deliberate ignorance concerning the foreseeable result, 

due to the proposed exemption, of increased near-term CO2 emissions. The commenter pointed 

out that EPA’s proposal will allow biomass-fueled stationary sources to be built and operated for 

years or decades without any demonstration that these sources are controlled to meet BACTbased CO2 emissions limits. The commenter goes on to say that EPA creates a competitive 

advantage for biomass facilities in that they will be relieved of demonstrating any form of BACT 

for GHG, including efficiency improvements, carbon capture and sequestration, or other 

technologies that fossil-fueled sources will be required to explore. The commenter further states 

that when it subsequently is determined that the biomass feedstocks fueling those facilities are 

and have been more damaging from a climate perspective than other available feedstocks, the 

Act does not provide a mechanism to “fix” the problem, unless and until the facilities undertake 

major modification. The commenter stated EPA’s proposed deferral runs completely counter to 

the fundamental design of the statutory program under which it is proposed. See Public Citizen, 

831 F.2d at 1113; Alabama Power, 636 F.2d at 360 (Agency’s attempt to interpret a statute is an 

unlawful overreach where it would thwart statutory purpose or command).

Response: EPA disagrees with commenter’s characterization of this action. EPA concluded in 

the Tailoring Rule that it is authorized under relevant case law to tailor applicability 

requirements to apply PSD and Title V to such sources in a phased-in manner, starting with the 

largest sources first. This action further implements Congressional intent by administering the 

CAA’s permitting programs in a step-wise manner that avoids absurd results and impossible 

administrative burdens stemming from the scientific uncertainty associated with biogenic 

emissions of CO2 from stationary sources. 

Comment: Commenter 0350.1 stated EPA can never justify a departure from the CAA statutory 

language and design on purely policy grounds. The commenter stated that absent any basis in 
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70

law or science, the only plausible explanation for EPA’s proposal is that the Agency is 

promoting a policy, or political, preference, as justification for avoiding the clear statutory 

requirements of the CAA. The commenter noted that EPA’s authority under the Act, however, 

does not include administrative discretion to avoid statutory commands in order to create de 

facto policy-based economic subsidies for particular industries and cited a recent Supreme Court 

case where EPA was reminded that the Agency’s policy discretion is limited by statute, not the 

other way around. (Massachusetts v. EPA, 549 U.S. 497, 532-35 2007). The commenter 

continued by noting that an agency may not “avoid the Congressional intent clearly expressed in 

the [statutory] text simply by asserting that its preferred approach would be better policy.”

(Engine Mfrs. Ass'n v, EPA, 88 F.3d 1075, 1089 (D.C. Cir. 1996). And yet, that is precisely what 

EPA attempts here, without providing any justification, never mind the “extraordinarily 

convincing justification” required in such circumstances. Appalachian Power Company v. EPA, 

249 F.3d 1032, 1041 (D.C. Cir. 2001).

Response: EPA disagrees with the commenter’s view that this action is based purely on policy 

grounds or costs and is unsupported by the law or science. As EPA explained in the preamble 

and in our other responses to this commenter, this interim deferral represents a permissible 

application of well-established administrative law doctrines, necessitated by the scientific 

uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a regulatory 

scheme that implements the CAA in a step-wise fashion designed to minimize administrative 

burdens and avoid unnecessary regulation of de minimis amounts of air pollution. 

Comment: Commenter 0350.1 stated EPA’s policy arguments do not support any exemption or 

deferral. The commenter stated the land-based accounting conventions used in the Inventory 

cannot answer the questions essential to an applicability determination under the PSD and Title 

V permitting programs, as the inventory’s conventions are backward-looking and provide a 

snapshot of carbon stock changes across wide geographical areas over a handful of years, and the 

PSD and Title V program require quantification of a particular facility’s projected emissions and 

the application of emission limits and controls in order to reduce them. The commenter noted it 

is puzzling that EPA then proposes to defer regulation for 3 years so that it can explore an 

Inventory-style land-based accounting system for use in applicability determinations, and the 

commenter stated EPA’s approach is unlawful and scientifically indefensible. The commenter 

pointed out that analysis of off-site future sequestration has no place in pre-construction permit 

applicability determinations under the CAA, and this should be obvious to EPA. The commenter 

noted that EPA’s concept of a forward-looking, land-based “baseline” for analysis of facilitylevel impacts is similarly misplaced, although noted that such an approach may have a place in 

evaluating case-by-case BACT determinations or in BACT guidance, but not for PSD and Title 

V applicability. The commenter further stated that policy arguments about domestic energy 

independence or the promotion of “renewable fuels,” whether pursued by state or federal 

agencies, are not related to the fundamental purpose of the permitting requirements of the statute, 

that is, the reduction of emissions of air pollutants. EPA’s attempt to base an exemption from the 

permitting requirements on such policy arguments, clearly disregards not only statutory language 

and structure, but also the statute’s fundamental purpose.

The commenter noted that the only state that has analyzed the best available scientific 

information, Massachusetts, has now decided to tightly restrict eligibility of biomass-based 

power for state renewable energy credits. The commenter indicated that Massachusetts 
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71

suspended biomass units for the renewable portfolio standard (RPS), commissioned a research 

study by Manomet Center for Conservation Science, and the study findings show that net GHG 

emission from biomass combustion to generate electricity in utility-scale plants are higher than 

when using coal (40 year basis), and when compared to natural gas, net GHG emissions from 

biomass combustion are still higher after 90 years. The commenter indicated that Massachusetts 

then proposed its revised regulation in May 2011 to (1) narrowly define biomass to include 

residues, limited thinning, and salvage wood, but not healthy whole trees; (2) require a 50 

percent reduction in GHG over 20 years, as compared to a natural gas-fired electric generating 

facility; (3) establish site-sensitive restrictions on woody biomass removal, ranged from 40 

percent by weight to 0 percent; and (4) create minimum efficiency standards for generators, of 40 

percent before qualifying for renewable energy credits from use of biomass. The commenter 

pointed out that the actions taken by Massachusetts contradict EPA’s position that its proposed 

deferral is consistent with state policies.

Response: EPA disagrees with the commenter’s view that this action is unsupported by the law, 

policy or science. The comment underscores the complexity of the science associated with 

accounting for biogenic CO2 emissions as part of the PSD and Title V permitting programs. As 

discussed in the preamble, EPA is using the time under this interim deferral to study the science 

surrounding biogenic CO2 emissions and is developing an accounting framework to assist 

permitting programs and sources. EPA will consider the information about the carbon lifecycle 

presented by this commenter, as well as others, as it conducts this study and develops the 

accounting framework. 

Comment: Commenter 0084.1 agreed that the de minimis doctrine provides EPA with sufficient 

authority to defer permitting for biogenic CO2 emissions; however, there is a more fundamental 

statutory basis − one that actually obviates the need for EPA to engage in mere deferral and then 

further study with respect to biogenic CO2 emissions. The commenter reasoned that unless EPA 

makes an endangerment finding for a particular pollutant stream, it may not regulate the stream

under CAA. The commenter asserted that EPA has never made the necessary endangerment 

finding for biogenic CO2 emissions per se. The commenter continued that the only GHG-related 

endangerment finding that EPA has ever made related to GHG emissions from certain classes of 

motor vehicles, all of which EPA understood to combust fossil fuels predominantly. The 

commenter noted that in the FR of said endangerment finding, EPA’s description of and 

justification for the finding did not once mention the word “biogenic,” ''biomass,'' “biofuel,” or 

“ethanol, thus EPA has never determined the combustion or decomposition of biogenic materials 

cause or contribute significantly to air pollution. As a result, the commenter noted, EPA lacks 

authority to bring biogenic GHG emissions within the domain of PSD and Title V. The 

commenter stated that until EPA makes an endangerment finding biogenic GHG emissions 

cannot constitute “a pollutant subject to regulation” for PSD and Title V purposes. Consequently, 

the commenter requested that EPA repeal applicability of biogenic CO2 to PSD and Title V 

indefinitely.

Response: EPA appreciates the commenter’s support for the interim deferral. EPA disagrees 

with the commenter’s arguments pertaining to the status of CO2 as a regulated pollutant and the 

endangerment and cause-and-contribute findings. A pollutant becomes “subject to regulation”

when the pollutant is subject to either a provision in the CAA, or a nationally-applicable 

regulation codified by the Administrator. Comments concerning biogenic CO2 as a regulated 
11.0 Rationale and Legal Justification for Interim Deferral

72

pollutant and CO2’s inclusion in the GHG air pollutant subject to regulation are beyond the scope 

of this rulemaking and are not being reconsidered as part of this action. As explained in more 

detail in the “Endangerment and Cause or Contribute Findings for Greenhouse Gases Under 

Section 202(a) of the Clean Air Act” (74 FR 66496), and the Light Duty Vehicle Rule, the 

Agency has found that air pollution in the form of elevated concentrations of a group of six 

individual GHG in the atmosphere, including CO2, may reasonably be anticipated to endanger 

both public health and public welfare and that emissions from new motor vehicles of an air 

pollutant composed of this same group of GHG contributes to this air pollution. In the Light 

Duty Vehicle Rule EPA set standards applicable to emissions of this air pollutant. Once GHG 

became subject to action control under the light-duty vehicle rule, applicability of the PSD and 

Title V permitting programs was triggered under the CAA.

Comment: Commenter 0118.1 proposed that EPA apply, for three years, PSD and Title V 

requirements to all facilities that have the potential for net biogenic CO2 at or above Tailoring 

Rule thresholds. The commenter declared that this approach provides a generalized technical 

review, which is easy to administer because the “potential emissions” element of the screen is 

coarse. Commenter 0118.1 stressed that the screen must be ensure that environment and public 

interest are protected from facilities that will cause an increase in atmospheric CO2 burden.

Response: EPA disagrees with the commenter’s characterization of the state of the science and 

the rationale in support of this action. As explained in the preamble, EPA believes that based on 

information currently before the Agency, including information provided in response to the CFI 

and the proposal for this rule, that emissions from certain biomass feedstocks may be carbon 

neutral or de minimis but also believes based on the complexity of this evidence that the deferral 

to allow for further study is warranted. EPA is using the time under this interim deferral to study 

the science surrounding biogenic CO2 emissions and is developing an accounting framework to 

assist permitting programs and sources. This interim deferral represents a permissible application 

of well-established administrative law doctrines, necessitated by the scientific uncertainty 

surrounding the accounting of biogenic CO2 emissions, to develop a regulatory scheme that 

implements the CAA consistent with Congressional intent in a step-wise fashion designed to 

minimize administrative burdens and avoid unnecessary regulation of de minimis amounts of air 

pollution. Subsequent regulations to establish treatment of specific sources of biogenic emissions 

under the PSD and Title V programs, based on the results of the study and development of the 

accounting framework, are beyond the scope of this action.

Comment: Commenter 0054.1 is in general agreement with the approach and the rationale for 

deferring biogenic CO2 emissions, as described in the preamble to the proposed rule.

Response: EPA appreciates the commenter’s support for the deferral.

Comment: One commenter (0054.1) stated that an important reason for the three-year deferral 

period is to allow sufficient time to consider the unique characteristics and attributes of biogenic 

CO2 feedstocks, using the results from a detailed examination. Absent this deferral, there would 

be significant additional and unique complexities to implementing the PSD and Title V 

programs. As a result, there would be additional permitting burden in terms of time and 

resources requirements, resulting from the associated analysis that would be required for sources 

of biogenic CO2 emissions as well as permitting agencies.
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The commenter believes that, absent the deferral period and the completion of EPA’s full 

analysis of the unique technical issues associated with these diverse facilities emitting biogenic 

CO2, it would be particularly challenging for permitting authorities and facilities to process 

permits involving these emissions. Therefore, for the reasons cited above the FSI supports the 

proposed three-year deferral.

Response: EPA appreciates the commenter’s support for the interim deferral and agrees that the 

scientific uncertainties associated with biogenic CO2 emissions and lack of accounting 

methodologies, which EPA will address during the deferral period, will exacerbate the existing 

administrative burdens of permitting agencies, which EPA described in detail in the Tailoring 

Rule and in the preamble to this action.

Comment: Commenter 0064.1 stated EPA has the legal authority to enact a three-year deferral 

and to permanently exempt CO2 emissions from biomass fired sources. There is no basis under 

the Act to regulate biogenic emissions because the endangerment finding was limited to fossil 

fuel combustion from motor vehicles. The original petition for an endangerment finding, the 

Supreme Court opinion in Massachusetts v. EPA, and EPA’s eventual endangerment finding 

were limited to greenhouse gas emissions from motor vehicles. In its final Endangerment 

Finding, EPA states: “The only issue under CAA section 202(a) is whether the air pollution is 

reasonably anticipated to endanger, and whether emissions from one domestic source category—

new motor vehicles—cause or contribute to this air pollution.” (74 FR 66496, 66521) 

Even if EPA considers its endangerment finding to extend to sources other than motor vehicles, 

the findings do not expressly address biomass sources. Therefore, EPA has inherent discretion to 

distinguish biogenic and non-biogenic emissions for purposes of a deferral or permanent 

exemption. Exclusion of biomass emissions from the Tailoring Rule can also be defended as a de 

minimis exemption supported by longstanding case law. The carbon neutrality of biomass 

emissions means that the net effect is not only de minimis but likely has a beneficial effect 

(especially if compared to combustion of fossil fuels).

Response: EPA appreciates the commenter’s support for the interim deferral. EPA disagrees 

with the commenter’s arguments pertaining to the status of CO2 as a regulated pollutant and the 

characterization of the endangerment and cause and contribute findings. Comments concerning 

biogenic CO2 as a regulated pollutant and CO2’s inclusion in the GHG air pollutant subject to 

regulation are beyond the scope of this rulemaking and are not being reconsidered as part of this 

action. As explained in more detail in the “Endangerment and Cause or Contribute Findings for 

Greenhouse Gases Under Section 202(a) of the Clean Air Act” (74 FR 66496), and the Light 

Duty Vehicle Rule, the Agency has found that air pollution in the form of elevated 

concentrations of a group of six individual GHG in the atmosphere, including CO2, may 

reasonably be anticipated to endanger both public health and public welfare and that emissions 

from new motor vehicles of an air pollutant composed of this same group of GHG contributes to 

this air pollution. In the Light Duty Vehicle Rule EPA set standards applicable to emissions of 

this air pollutant. 

Comment: Commenter 0079.1 stated that excluding biogenic CO2 emissions from the “Subject 

to Regulation” definition will not address those emissions for PSD applicability if EPA regulates 

GHG under an NSPS for utilities or refineries. By embedding the deferral of biogenic CO2
11.0 Rationale and Legal Justification for Interim Deferral

74

emissions in the definition of the term “subject to regulation,” the Agency only “solves” the 

problem it has identified temporarily – until an NSPS is issued applicable to CO2. The 

commenter provided the text of 40 CFR 52.21(b)(50) that defines the term “regulated NSR 

pollutant,” and 40 CFR 52.21(b)(49), that defines the term “subject to regulation.” EPA proposes 

to place the biomass deferral in the “subject to regulation” definition, which will exclude 

biogenic CO2 emissions to the extent CO2 becomes a regulated NSR pollutants under the “any 

pollutant otherwise subject to regulation” clause of Section 52.21(b)(50)(iv). However, it would 

not exclude biogenic CO2 emissions to the extent CO2 becomes a regulated NSR pollutant under 

the “any pollutant that is subject to any standard promulgated under section 111 of the Act”

clause of Section 52.21(b)(50)(ii). The thresholds and exclusions included in subparagraph 

52.21(b)(49) are apparently applicable only to pollutants that come into the program through the 

“subject to regulation” language. However, that language is found nowhere in the provision that 

makes NSPS pollutants “regulated NSR pollutants” under EPA’s rules.

The commenter understands that EPA embedded the thresholds for GHG and the phasing in of 

the program in the new “subject to regulation” definition for the purpose of avoiding the need for 

states to revise their state implementation plans (SIPs). An unintended consequence of revising 

the rules in this way is that it does not appear to address the effects of EPA issuing an NSPS for 

GHG. EPA has agreed to issue an NSPS for the utility and refining sectors in the near future 

(with the first standard in May of 2012), long before the three-year deferral proposed here would 

expire. Therefore, EPA’s proposed regulatory language will not have the desired effect of 

actually deferring biogenic CO2 emissions.

Response: EPA appreciates the views of the commenter but notes that regulation of CO2, 

including from biogenic sources, under the CAA Section 111 NSPS program is beyond the scope 

of this action. 

Comment: Commenter 0126.1 stated that the Agency applied the “administrative necessity”

doctrine in fashioning the regulatory limits of the Tailoring Rule, but stated that this and other 

doctrines were inapplicable to its considerations regarding biomass.

Response: As discussed in the preamble, EPA is using the time under this interim deferral to 

study the science surrounding biogenic CO2 emissions and is developing an accounting 

framework to assist permitting programs and sources. This interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis sources of air pollution. Subsequent regulations to establish treatment of specific sources 

of biogenic emissions under the PSD and Title V programs, based on the results of the study and 

development of the accounting framework, are beyond the scope of this action.

11.2 Permitting is Required

Comment: Many commenters (0010, 0023E, 0023G, 0029, 0030, 0045, 0049.1, 0066, 0101.1, 

0104.1, 0115.1, 0137.1, and 0145.1) are opposed to the deferral. Commenter 0101.1 cited a study 

that found higher CO2 emissions from biomass than from coal combustion and stated the study 
11.0 Rationale and Legal Justification for Interim Deferral

75

indicated permitting is necessary to evaluate fuel sources, efficiencies, and other project 

complexities. Commenter 0104.1 argued that permitting is critical for peaking GHG emissions 

and joined other commenters (0010, 0023E, 0023H, 0030, 0104.1, 0145.1) with concerns that 

deferral will encourage projects that will consume whole trees and increase CO2 concentrations 

in the near term. Commenter 0104.1 suggested that EPA amend the proposal to defer only 

feedstocks which are clearly carbon neutral (e.g., biogenic wastes), but suggests the carbon 

neutrality of questionable feedstocks (e.g., whole trees) be resolved during the proposed deferral 

period. Additionally, Commenter 0104.1 requested that EPA investigate Massachusetts 

regulations for qualifying for the RPS. Commenter 0023E argued that the Act does not support 

permanent or temporary permitting exemptions for biogenic CO2. Commenter 0023G supported 

improvement of accounting methods and recognized that climate impacts are feedstock specific 

but objected to complete exemption of biogenic emissions for three years, because the 

commenter sees the permitting process as a method for ensuring sustainability and use of wastes, 

residues, herbaceous and short rotation wood while preserving food production. Commenter 

0014.1 stated industry is familiar with the permitting process and will not be unduly burdened 

with biogenic CO2 permitting.

Response: EPA appreciates the views of the commenters and notes that it has received other 

comments taking an opposing view of the science. EPA believes these comments underscore the 

complexity of the science associated with accounting for biogenic CO2 emissions as part of the 

PSD and Title V permitting programs. EPA believes that based on information currently before 

the Agency, including information provided in response to the CFI and the proposal for this rule, 

that emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, but further believes based on this evidence that the deferral to allow for 

further study is warranted. As discussed in the preamble, EPA is using the time under this 

interim deferral to study the science surrounding biogenic CO2 emissions and is developing an 

accounting framework to assist permitting programs and sources. In addition, EPA is conducting 

an independent peer review by the SAB of the science and accounting methodologies associated 

with biogenic CO2 emissions. EPA will consider the information about the carbon lifecycle 

presented by these commenters, as well as others, as it conducts this study and develops the 

accounting framework. EPA considers the commenters’ views about the economics of the 

biomass industry to be beyond the scope of this action but notes that business decisions are made 

based on a number of factors, not just regulatory requirements.

Comment: Commenter 0048.1 stated that during the three-year deferral, safeguards are needed 

to prevent new biomass incinerators, as well as mixed waste incinerators burning biomass, from 

being permitted without adequate safeguards to protect our air, water, soil, and public health.

Response: EPA appreciates the commenter’s views. As EPA explained in the preamble, this 

interim deferral represents a permissible application of well-established administrative law 

doctrines, necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2

emissions, to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent to protect air quality in a step-wise fashion designed to minimize 

administrative burdens and avoid unnecessary regulation of de minimis amounts of air pollution. 

Subsequent regulations to establish treatment of specific sources of biogenic emissions under the 

PSD and Title V programs, based on the results of the study and development of the accounting 

framework, are beyond the scope of this action.
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Comment: Commenter 0049.1 stated there is no scientific basis for completely ignoring carbon 

pollution from biomass, and the exemption of biomass emissions from a source’s PTE introduces 

regulatory bias that accelerates biomass burning, particularly burning of whole trees. 

Commenter 0049.1 stated all carbon emissions from major sources should count and 

preconstruction and operation permits should be required during the study period.

Response: EPA appreciates the views of the commenter and notes that it has received other 

comments taking an opposing view of the science. EPA considers the commenter’s views about 

the economics of the biomass industry to be beyond the scope of this action but notes that 

business decisions are made based on a number of factors, not just regulatory requirements. 

EPA believes these comments underscore the complexity of the science associated with 

accounting for biogenic CO2 emissions as part of the PSD and Title V permitting programs. 

EPA agrees that based on information currently before the Agency, including information 

provided in response to the CFI and the proposal for this rule, that emissions from certain 

biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2, but 

further believes based on this evidence that the deferral to allow for further study is warranted. 

As discussed in the preamble, EPA is using the time under this interim deferral to study the 

science surrounding biogenic CO2 emissions and is developing an accounting framework to 

assist permitting programs and sources. This interim deferral represents a permissible application 

of well-established administrative law doctrines, necessitated by the scientific uncertainty 

surrounding the accounting of biogenic CO2 emissions, to develop a regulatory scheme that 

implements the CAA consistent with Congressional intent in a step-wise fashion designed to 

minimize administrative burdens and avoid unnecessary regulation of de minimis amounts of air 

pollution. Subsequent regulations to establish treatment of specific sources of biogenic emissions 

under the PSD and Title V programs, based on the results of the study and development of the 

accounting framework, are beyond the scope of this action.

Comment: Commenter 0049.1 stated EPA policies must reflect the science of biomass carbon 

accounting and forest protection, and EPA must create a path for treating biomass emissions 

correctly under the CAA. The commenter stated EPA must work with other federal agencies to 

develop methods and criteria to determine whether biomass is sustainable without degrading 

ecological health of the forest and its dependent biota. 

Response: See previous response to commenter 0049.1. In addition, EPA agrees on the 

importance of working with other federal agencies, as well as scientists and state and local 

agencies, to understand the forest ecology and developing accounting methodologies. 

Comment: Commenters 0065.1, 0106.1, 0118.1, 0119.1, 0128.1, 0141, 0143.1, 0275, 0319, and 

0351 are opposed to the deferral. Commenter 0118.1 noted that a deferral – amounting to 

complete suspension of the regulations for three years– is an extreme step contrary to legal 

requirements that EPA protect the environment and the public interest, and it is unnecessary to 

based on the reasons given in the proposal. Commenter 0119.1 is opposed because it will allow 

biomass facilities to be permitted or modified at the expense of forests, climate, and local 

communities. Additionally, commenter 0119.1 noted that the effect of the three year deferral 

could actually be much longer because once permitted, PSD regulations will not apply (perhaps 

for decades) until a major modification is requested. Commenter 0128.1 noted that the deferral 
11.0 Rationale and Legal Justification for Interim Deferral

77

sets a bad precedent for CAA compliance and fails to acknowledge the important differences in 

biomass energy applications that may or may not achieve net GHG reductions. Additionally, the 

commenter asserts that there will be no federal limits on biomass burning in the foreseeable 

future which could create perverse incentives that lead to only marginal gains in air quality. 

Commenter 0275 further stated that biomass burning is not a solution but is a severe problem in 

and of itself, and is the worst thing we could do from a climate change perspective.

Response: EPA disagrees with commenters’ views that the interim deferral is not based on 

sound legal rationales. As EPA explained in the preamble, this interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis amounts of air pollution. EPA disagrees with the commenters that the deferral may 

exceed three years or would necessarily lead to a degradation of air quality in violation of 

Congressional intent. EPA notes that the issue of subsequent applicability of the PSD and Title 

V programs to facilities that may be permitted during the deferral period is beyond the scope of 

this action and will be addressed in any rulemakings subsequent to the conclusion of the 

scientific study and development of the accounting methodologies. In response to the comment 

opposed to biomass burning, EPA notes that a variety of Federal and State policies have 

recognized that some types of biomass can be part of national strategy to reduce dependence on 

fossil fuels and to reduce emissions of GHG.

Comment: Commenter 0150.1 noted that EPA should not have removed biogenic carbon 

emissions from consideration of the Tailoring Rule, and further should not take more than one 

year to develop appropriate carbon accounting rules. Moreover, the commenter asserted that a 

three-year delay will allow a number of biomass to electricity facilities to be built that will 

significantly increase US CO2 emissions.

Response: EPA disagrees with the commenter. As explained in the preamble, EPA concluded it 

would need the three years of the deferral period to complete the scientific study and to develop 

the accounting framework for biogenic CO2 emissions. In fact, as explained in the preamble, it 

is possible that the subsequent rulemaking, depending on the nature of EPA’s determinations, 

would supersede this rulemaking and become effective in fewer than three years. The deferral 

period is no longer than necessary to complete these tasks in order to develop a regulatory 

scheme that implements the CAA consistent with Congressional intent in a step-wise fashion 

designed to minimize administrative burdens and avoid unnecessary regulation of de minimis 

amounts of air pollution. Subsequent regulations to establish treatment of specific sources of 

biogenic emissions under the PSD and Title V programs, based on the results of the study and 

development of the accounting framework, are beyond the scope of this action.

Comment: Commenter 0130.1 stated that EPA’s recent decision to exempt CO2 emissions from 

the combustion of biomass under the CAA regulation for the next three years will place 

communities across America at significant risk.
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Response: EPA appreciates the views of the commenter and notes that it has received other 

comments taking an opposing view of impact of the deferral. 

Comment: Commenter 0128.1 noted that the deferral sets a bad precedent for CAA compliance 

and fails to acknowledge the important differences in biomass energy applications that may or 

may not achieve net GHG reductions. Additionally, the commenter asserts that there will be no 

federal limits on biomass burning in the foreseeable future which could create perverse 

incentives that lead to only marginal gains in air quality. The commenter further contends that 

the deferral puts states in the difficult position of developing their own methodologies that could 

lead to an uneven patchwork of regulatory approaches.

Response: EPA disagrees with commenter’s characterization of this action and believes the 

comment underscores the complexity of the science surrounding biogenic emissions of CO2 and 

their impact on the carbon cycle. As EPA explained in the preamble, this interim deferral 

represents a permissible application of well-established administrative law doctrines that EPA 

has used in other aspects of implementing the PSD program and other parts of the CAA. As 

discussed in the preamble, EPA is using the time under this interim deferral to study the science 

surrounding biogenic CO2 emissions and is developing an accounting framework to assist 

permitting programs and sources. EPA notes that it has received comments taking an opposing 

view of the impact of the deferral on the development of the biomass industry. In addition, EPA 

notes that a variety of Federal and State policies have recognized that some types of biomass can 

be part of national strategy to reduce dependence on fossil fuels and to reduce emissions of 

GHG.

Comment: Two commenters (0138.1, 0131.1) objected to EPA’s expressed concern about the 

proposal to defer regulation of deter safeguards for biogenic carbon dioxide emissions. The 

commenter agreed that EPA should study GHG CO2 emissions from biogenic energy sources, 

but suspending regulation of biogenic emissions is not supported by good science.

Response: EPA appreciates the commenters’ support for the scientific study but disagrees with 

the view that the deferral is not based on “good” science. EPA notes that it has received other 

comments taking an opposing view of the science, which underscores the complexity of the 

science associated with accounting for biogenic CO2 emissions as part of the PSD and Title V 

permitting programs. EPA agrees that based on information currently before the Agency, 

including information provided in response to the CFI and the proposal for this rule, that 

emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, but further believes based on this evidence that the deferral to allow for 

further study is warranted. As discussed in the preamble, EPA is using the time under this 

interim deferral to study the science surrounding biogenic CO2 emissions and is developing an 

accounting framework to assist permitting programs and sources. In addition, EPA is conducting 

an independent peer review by the SAB of the science and accounting methodologies associated 

with biogenic CO2 emissions. EPA will consider the information about the carbon lifecycle 

presented by these commenters, as well as others, as it conducts this study and develops the 

accounting framework. EPA also notes that a variety of Federal and State policies have 

recognized that some types of biomass can be part of national strategy to reduce dependence on 

fossil fuels and to reduce emissions of GHG.
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Comment: One commenter (0138.1) projected that biomass power generation will quadruple 

over the next ten years, and this rapid growth will have dramatic consequences for forests and 

carbon emissions because industry data demonstrate that the overwhelming majority of existing 

bio-energy plants use wood as fuel, and the overwhelming majority of new plants being planned 

and built will use wood as fuel. The commenter stated that plants co-firing biomass have a 

particular need for wood, rather than agricultural crops, since their boilers and emissions control 

equipment are not equipped to deal with the slagging and fouling that can accompany 

combustion of agricultural materials, and processed wood is the fuel of choice for coal plants 

wanting to co-fire biomass. The commenter stated that the three-year deferral on biomass 

pollution safeguards would create a flawed incentive for new and expanded power plants to burn

biomass instead of other fuels and stated that because the supply of sustainable, low-carbon 

forestry wastes is extremely limited, expanding the biomass power industry will require burning 

whole trees. The commenter stated that EPA should not be creating incentives for burning 

biomass without safeguards for forests and the commenter provided projections of wood usage 

and CO2 emissions associated with industrial plans to expand use of biogenic fuels. The 

commenter stated that the projected growth in wood consumption and the associated growth in 

CO2 emissions are grounds for EPA to reject the proposed deferral.

Response: EPA notes that it has received other comments taking an opposing view of the 

impact of the deferral and the science, which underscores the complexity of the science 

associated with accounting for biogenic CO2 emissions as part of the PSD and Title V permitting 

programs. EPA believes based on information currently before the Agency, including 

information provided in response to the CFI and the proposal for this rule, that emissions from 

certain biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2,

but also believes based on the complexity of this evidence that the deferral to allow for further 

study is warranted. As discussed in the preamble, EPA is using the time under this interim 

deferral to study the science surrounding biogenic CO2 emissions and is developing an 

accounting framework to assist permitting programs and sources. This interim deferral represents 

a permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis amounts of air pollution. EPA will consider the information about the carbon lifecycle 

presented by the commenter, as well as others, as it conducts this study and develops the 

accounting framework prior to developing subsequent regulations. EPA considers the 

commenter’s views about the economics of the biomass industry to be beyond the scope of this 

action but notes that business decisions are made based on a number of factors, not just 

regulatory requirements.

Comment: Commenter 0269 opposed deferral and stated that the biomass incinerators being 

proposed and constructed are a fast grab for scarce taxpayer dollars, are economically 

unconscionable, are economically unsustainable without major subsidies, are environmentally 

unconscionable, and are environmental travesties. The commenter also thought these sources 

should be subject to the same rules as other sources.

Response: EPA considers this commenter’s views about the economics of the biomass industry 

to be beyond the scope of this action.
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Comment: Commenter 0350.1 stated EPA’s proposed exemption is unlawful, arbitrary, and 

capricious. The commenter opposed the blanket three-year exemption on policy grounds 

because if finalized it will have the effect of increasing uncontrolled near-term emissions of CO2. 

The commenter stated EPA has not justified its proposal, either as a matter of law or science. 

The commenter stated that the blanket exemption is a plain violation of the statute’s language 

and Congressional intent. Commenter 0350.1 stated EPA’s only lawful course of action is to 

require PSD and Title V permits for every major source that emits CO2 at the Tailoring Rule 

thresholds. The commenter noted that inquiries concerning allegedly clean fuel feedstocks for 

each facility must be resolved on a case-by-case basis as part of the BACT analysis.

Response: EPA disagrees with commenter’s views that the interim deferral is arbitrary and 

capricious and not based on sound legal rationales or science. As EPA explained in the preamble, 

this interim deferral represents a permissible application of well-established administrative law 

doctrines, necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2

emissions, to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent in a step-wise fashion designed to minimize administrative burdens and 

avoid unnecessary regulation of de minimis amounts of air pollution. EPA believes that based on 

information currently before the Agency, including information provided in response to the CFI 

and the proposal for this rule, that emissions from certain biomass feedstocks may have a 

neglible impact on atmospheric concentrations of CO2, but also believes based on this evidence 

that the deferral to allow for further study is warranted. As discussed in the preamble, EPA is 

using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

EPA considers the commenter’s views on the requirements of a BACT analysis to be beyond the 

scope of this action. 

Comment: Commenter 0350.1 stated EPA’s proposed exemption for biogenic CO2 emissions is 

unlawful. The commenter stated the CAA language and statutory design require the “emissions”

of “any air pollutant” including biogenic CO2 count toward PSD and Title V applicability. The 

commenter stated that the plain language of the CAA and EPA’s practice for decades makes 

absolutely clear that, in determining whether a facility must apply for a PSD or Title V permit 

(the “applicability determination”), all emissions of an air pollutant directly from the facility 

must be taken into account; regardless of the fuel types used at a source, if the relevant pollutant 

emission threshold is met, a preconstruction permit must be held, and the emissions limits it 

contains complied with, when the source is operational.

The commenter indicated that Section 165(a) of the Act requires that prior to the commencement 

of construction of any major emitting facility, a permit must be issued for the proposed facility 

based on the “best available control technology for each pollutant” emitted by the facility. 42 

U.S.C.§§ 7475(a)(1), (a)(4)(emphasis added). The commenter noted the definition of “major 

emitting facility” in Section 169(a) also hinges on the emission of specified quantities of “any air 

pollutant.” 42 U.S.C. §7479(1)(emphasis added). The commenter cited a court case where the 

Supreme Court, in Massachusetts v. EPA, 549 U.S. 497, 528-30 (2007), firmly established that 

CO2 is an “air pollutant” within the meaning of the CAA, and that holding applies to all CO2, not 

just to “fossil-fuel-based” CO2. The commenter stated biogenic CO2, like all other CO2, is an air 

pollutant. The commenter noted that nothing in the language of the CAA permits EPA to count 
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81

less than all of the air pollutant that is emitted, or to carve out an exemption for some molecules 

of an air pollutant, depending on the fuel type from which it is produced. The PSD (and Title V) 

permitting requirements are triggered if the amount of emissions generated by the facility make it 

a “major emitting facility.” 42 U.S.C. §7479(1). The statutory framework and EPA’s 

longstanding interpretation of that framework10 requires assessment of how much of the air 

pollutant is emitted by the source. Specifically, a facility becomes a “major emitting facility”

based on the amounts of pollutants which it “emit[s] or ha[s] the potential to emit.” 42 USC § 

7479(1)(emphasis added). Similarly, Section 165(a) of the Act requires that a facility’s permit 

state the “emission limitations for such facility,” and applies BACT for each pollutant “emitted 

from or which results from such facility.” 42 U.S.C.§§ 7475(a)(1), (a)(4)(emphasis added). In 

other words, if the relevant threshold is met by a facility’s at the stack and fugitive emissions, 

compliance with the BACT requirement is mandatory

The commenter stated there is nothing about biogenic CO2 emissions that justifies the radical 

departure proposed by EPA from the statute’s permitting framework. In short, CO2, regardless 

of its source, is an air pollutant, and it is the amount of a facility’s emissions that determines 

permit program “applicability,” that is, whether the facility must hold PSD and Title V permits.

Response: EPA disagrees with commenter’s views that the interim deferral is unlawful. As EPA 

explained in the preamble, this interim deferral represents a permissible application of wellestablished administrative law doctrines, which EPA has used to implement other aspects of the 

PSD program and other provisions of the CAA, necessitated by the scientific uncertainty 

surrounding the accounting of biogenic CO2 emissions, to develop a regulatory scheme that 

implements the CAA consistent with Congressional intent in a step-wise fashion designed to 

minimize administrative burdens and avoid unnecessary regulation of de minimis amounts of air 

pollution. EPA notes that the Supreme Court recently described the appropriateness of this 

approach as follows: “Agencies, like legislatures, do not generally resolve massive problems in 

one fell regulatory swoop;” and instead they may permissibly implement such regulatory 

programs over time, “refining their preferred approach as circumstances change and as they 

develop a more nuanced understanding of how best to proceed.” Massachusetts v. EPA, 549 U.S. 

497, 524 (2007). EPA believes that based on information currently before the Agency, including 

information provided in response to the CFI and the proposal for this rule, that emissions from 

certain biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2,

but also believes based on the complexity of this evidence that the deferral to allow for further 

study is warranted. As discussed in the preamble, EPA is using the time under this interim 

deferral to study the science surrounding biogenic CO2 emissions and is developing an 

accounting framework to assist permitting programs and sources. Once that work is complete the 

Agency intends to undertake a rulemaking to establish the treatment of these emissions in the 

PSD and Title V programs. At this time we do not have enough information or analysis to 

establish an accounting methodology or treatment for specific sources biogenic CO2 emissions in 

the PSD and Title V programs. 

11.3 Permitting is Not Required

Comment: Numerous commenters (0013.1, 0015.1, 0023J, 0032.1, 0039.1, 0042.1, 0043.1, 

0045.1, 0046.1, 0047.1, 0050.1, 0051.1, 0053.1, 0056.1, 0057.1, 0060.1, 0062.1, 0064.1, 0071.1, 

0072.1, 0074.1, 0077.1, 0078.1, 0082.1, 0084.1, 0086.1, 0087.1, 0089.1, 0093, 0094.1, 0095.1, 
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0096.1, 0099.1, 0100.1, 0107.1, 0109.1, 0111.1, 0114.1, 0117.1, 0121.1, 0122.1, 0123.1, 0124.1,

0126.1, 0129.1, 0135.1, 0139.1, 0140.1, and 0146) supported the proposal. Commenter 0071.1 

suggested that EPA should defer any regulation until new rules are in place. Commenters 0078.1 

and 0082.1 stated projects (including bio-energy development projects) should not have to face 

uncertainty and potentially unnecessary costs and delays related to permitting and BACT while 

EPA deliberates. Commenters 0053.1 and 0062.1 encouraged EPA to differentiate biogenic 

emissions at municipal wastewater and solid waste facilities from harvested biomass when 

studying the biogenic permitting program, and commenter 0062.1 stated that Step 2 of the 

Tailoring Rule will prompt permitting for a very large number of these facilities. Similarly, 

commenter 0087.1 noted that requiring permitting at certain projects (e.g., methane combustion 

projects) could be counterproductive because such projects result in lower potential for global 

warming, and commenter 0077.1 described plans and projects to use methane from wastewater 

facilities to displace fossil fuels. Commenters 0032, 0043.1, and 0136.1 stated that the deferral is 

useful to take the time to review the science and engage with experts in order to properly 

consider how biogenic carbon should be permitted. Commenters 0074.1, 0095.1, 0126.1 and 

0063.1 agreed that deferral of permitting is appropriate because science backs biogenic carbon 

neutrality, precedence has treated them as such, and regulation of de minimis emissions should 

be avoided. Commenter 0074.1 further stated that permitting is administratively infeasible 

through CAA programs. Commenter 0063.1 argued that the deferral of biogenic permitting 

requirements is appropriate because it will reduce dependence on fossil fuels, promote the use of 

renewable sources of energy, and reduce GHG emissions. Commenter 0086.1 supported the 

deferral and urges the EPA to adopt a categorical permitting exemption in line with EPA’s 

treatment of biogenic emissions in other policies. Commenter 0023A cited court decisions 

supporting EPA’s authority to exempt de minimis emissions from permitting and stated that since 

they pose no endangerment, biogenic emissions should be exempt from permitting.

Commenter 0100.1 provided a list of factors that should be considered to assess the net 

atmospheric impact of biogenic CO2 emissions. Commenter 0056.1 stated that recognizing the 

reduced lifecycle footprint of biogenic emissions will lower GHG emissions profiles and avoid 

major permitting, at projects (such as ethanol production or other alternative fuel ventures) that 

promote EPA goals under RFS2 by aiding development and availability of alternative fuel 

sources.

Commenter 0101.1 supported deferral because the following factors indicate permitting biogenic 

energy development projects would not be good usage of limited permitting resources:

1. Forestland in the United States is a net carbon sink.

2. EPA has sufficient information to conclude that some biogenic fuels have negligible 

impact on the net carbon cycle.

3. In some cases, the use of biogenic fuel would clearly reduce net atmospheric CO2 levels.

4. EPA has explicitly recognized that a permitting authority might determine that certain 

types of biomass by themselves represent BACT for GHG.

Response: EPA appreciates the commenters’ views in support of the deferral. EPA notes that it 

has received other comments taking an opposing view of the impact of the deferral and the 

science, which underscores the complexity of the science associated with accounting for 

biogenic CO2 emissions as part of the PSD and Title V permitting programs. EPA believes that 

based on information currently before the Agency, including information provided in response to 
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the CFI and the proposal for this rule, that emissions from certain biomass feedstocks may have a 

neglible impact on atmospheric concentrations of CO2, but also believes based on the complexity 

of this evidence that the deferral to allow for further study is warranted. As discussed in the 

preamble, EPA is using the time under this interim deferral to study the science surrounding 

biogenic CO2 emissions and is developing an accounting framework to assist permitting 

programs and sources. This interim deferral represents a permissible application of wellestablished administrative law doctrines, necessitated by the scientific uncertainty surrounding 

the accounting of biogenic CO2 emissions, to develop a regulatory scheme that implements the 

CAA consistent with Congressional intent in a step-wise fashion designed to minimize 

administrative burdens and avoid unnecessary regulation of de minimis amounts of air pollution. 

EPA will consider the information about the carbon lifecycle presented by these commenters, as 

well as others, as it conducts this study and develops the accounting framework prior to 

developing subsequent regulations establishing treatment for biogenic emissions under the PSD 

and Title V programs.

Comment: Commenter 0079.1 advises EPA to defer the implementation of its Tailoring Rule 

approach for all sources and emissions until at least 2013. If EPA does not implement this 

recommendation, the commenter supports the deferral of CO2 emissions from biomass 

combustion. 

Response: EPA appreciates the commenter’s views in support of the deferral but notes that the 

commenter’s request to defer implementation of the Tailoring Rule until 2013 is beyond the 

scope of this action and is not being reconsidered as part of this action.

11.4 Authority to Exempt de minimis Emissions

Comment: Commenter 0104.1 recognized EPA’s authority to exempt emissions based on the de 

minimis doctrine, but stated that the proposal did not clearly specify the timeframe for assessing 

whether biogenic emissions have de minimis impacts on public health and welfare with respect to 

the urgent need to peak GHG emissions as recognized by U.S. delegates in the 2010 conference 

in Cancun. The commenter went on to say that the appropriate time frame for assessing carbon 

neutrality and whether biogenic impacts are de minimis is one to three years and suggested that 

EPA’s authority to use the de minimis doctrine should be justified on a feedstock-specific basis. 

Response: EPA appreciates the commenter’s views in support of EPA’s decision to defer 

applicability of the PSD and Title V permitting programs to at least certain feedstocks and 

sources of biogenic emissions. EPA notes that it has received other comments taking an 

opposing view of the rationale in support of the deferral and the state of the science, which 

underscores the complexity of the science associated with accounting for biogenic CO2

emissions as part of the PSD and Title V permitting programs. EPA believes that based on 

information currently before the Agency, including information provided in response to the CFI 

and the proposal for this rule, that emissions from certain biomass feedstocks may have a 

neglible impact on atmospheric concentrations of CO2, but also believes based on this and other 

evidence that the deferral to allow for further study is warranted. As discussed in the preamble, 

EPA is using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

This interim deferral represents a permissible application of well-established administrative law 
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doctrines, necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2

emissions, to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent in a step-wise fashion designed to minimize administrative burdens and 

avoid unnecessary regulation of de minimis amounts of air pollution. EPA believes that the full 

three-year deferral period, as opposed to only one year, is necessary to complete this work and to 

develop any subsequent regulations to establish treatment of the PSD and Title V programs to 

specific biogenic sources of CO2 emissions.

Comment: Commenter 0086.1 cited previous EPA assertions of authority to exempt de minimis 

emissions, used the PSD rule’s exclusion of certain compounds from the definition of “volatile 

organic compound” and the PSD rule’s use of significant impact concentrations as precedence, 

and stated that biogenic emissions warrant a similar assertion, because the carbon neutrality and 

the rapid carbon cycle of biomass are sufficient to support a finding that biogenic CO2 emissions 

have a de minimis effect on human health or the environment. 

Response: EPA appreciates the commenter’s views in support of EPA’s decision to defer 

applicability of the PSD and Title V permitting programs to at least certain feedstocks and 

sources of biogenic emissions. The deferral is necessitated by the complexity surrounding the 

accounting of biogenic CO2 emissions, and is needed to give EPA and other permitting 

authorities time to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent in a step-wise fashion designed to minimize administrative burdens and 

avoid unnecessary regulation of de minimis amounts of air pollution. 

Comment: Commenter 0138.1 disagreed with EPA’s justification that some biomass feedstocks 

have a de minimis impact on carbon levels. The commenter stated that EPA has not 

demonstrated that “residue” materials decompose in a short period of time. It has also not 

justified treating such emissions, which are assumed to achieve parity with decomposition 

emissions in 10 – 15 years, are worthy of being treated as instantaneously carbon neutral. 

Further, the Agency has not demonstrated that such materials constitute the sole or even 

predominant source of fuel for the current and future biomass industry. EPA thus has not 

provided the required proofs that regulating biogenic CO2 would yield a gain of trivial or no 

value. Not only has EPA not provided the required proofs that its exemption is supportable or 

justified, but it cannot. The science does not exist to show that burning biomass emits only de 

minimis carbon emissions, and the Agency has admitted as much by stating that different kinds 

of biomass have different effects on emissions.

Burning biomass emits so much more carbon than burning fossil fuels because biomass powered 

electricity generating facilities are generally much less efficient than fossil fuel powered 

facilities, meaning whatever the source of biomass – whether it be waste, whole trees, or 

purpose-grown crops – emissions at the stack are much greater than emissions from generating 

the same amount of energy using coal, oil, or natural gas. For example, the air permit for the 

proposed 50 megawatt (MW) We Energies/Domtar biomass to energy plant in Rothschild, WI 

includes an emissions rate of 3,050 pounds of CO2 per megawatt hour (lb/MWH)–or a total of 

634,553 tons per year operating at 95% capacity, as compared with a gas-fired boiler which

would generate around 1,130 lb of CO2/ MWH or 235,097 tons of CO2 per year given the same 

size, operating and capacity assumptions. The commenter provides CO2 emissions for existing 

facilities using biofuels, and states that those emissions are significant, over 89 million tons, and 
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in the state of Maine, emissions from biomass burning are larger that emissions from the fossil 

fuel burning power sector. 

Response: EPA disagrees with the commenter’s characterization of EPA’s rationale. As 

explained in the preamble, EPA believes that based on information currently before the Agency, 

including information provided in response to the CFI and the proposal for this rule, that 

emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 

evidence that the deferral to allow for further study is warranted. EPA is using the time under 

this interim deferral to study the science surrounding biogenic CO2 emissions and is developing 

an accounting framework to assist permitting programs and sources. This interim deferral 

represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. EPA will consider the information about the 

carbon lifecycle presented by the commenter, as well as others, as it conducts this study and 

develops the accounting framework prior to developing subsequent regulations establishing 

treatment for specific sources of biogenic emissions of CO2 under the PSD and Title V programs. 

11.5 De minimis Authority Does Not Apply

Comment: Commenter 0104.1 stated that EPA does not have authority to depart from current 

regulatory accounting provisions as proposed, because the proposal draws its exemption too 

broadly by including types of biomass feedstocks that have very different characteristics and 

whose burning will result in large GHG increases over a period of several decades. The 

commenter argued that the Agency therefore has not met its burdens to “depart no more than 

necessary to render the requirement administrable” and cited Alabama Power v. Costle, 636 F.2d 

323, 359 (D.C. Cir. 1980).

Response: EPA disagrees with the commenter’s characterization of EPA’s rationale. As 

explained in the preamble, EPA believes that based on information currently before the Agency, 

including information provided in response to the CFI and the proposal for this rule, that 

emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 

evidence that the deferral to allow for further study is warranted. EPA is using the time under 

this interim deferral to study the science surrounding biogenic CO2 emissions and is developing 

an accounting framework to assist permitting programs and sources. This interim deferral 

represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. EPA will consider the information about the 

carbon lifecycle presented by the commenter, as well as others, as it conducts this study and 

develops the accounting framework prior to developing subsequent regulations establishing 

treatment for specific sources of biogenic emissions of CO2 under the PSD and Title V programs.
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Comment: Commenters 0104.1 and 0137.1 disagreed with proposal language asserting that 

biogenic carbon emissions are de minimis and stated that EPA did not provide adequate support 

for invoking the de minimis doctrine, because “current science overwhelmingly demonstrates 

that a blanket assumption of the carbon neutrality of non-wood[-]waste biomass, such as 

standing trees, is patently unreasonable.” These commenters state that standing trees are the only 

viable feedstock that can satisfy the rapidly increasing demand for biogenic fuels in response to 

RPS and other incentives in the U.S. and Europe. Based on projections of the growth in demand 

for whole trees, commenter 0137.1 concluded that EPA is taking an unreasonable risk relying on 

the unproven potential for standing trees to be carbon neutral to justify this proposal.

Response: EPA disagrees with the commenter’s characterization of EPA’s rationale. As 

explained in the preamble, EPA believes that based on information currently before the Agency, 

including information provided in response to the CFI and the proposal for this rule, that 

emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 

evidence that the deferral to allow for further study is warranted. EPA is using the time under 

this interim deferral to study the science surrounding biogenic CO2 emissions and is developing 

an accounting framework to assist permitting programs and sources. This interim deferral 

represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. EPA will consider the information about the 

carbon lifecycle presented by the commenters, as well as others, as it conducts this study and 

develops the accounting framework prior to developing subsequent regulations establishing 

treatment for specific sources of biogenic emissions of CO2 under the PSD and Title V programs.

Comment: Commenter 0350.1 stated EPA has not met its heavy burden of proof under the “de 

minimis” doctrine. The commenter noted that neither of EPA’s claims (that some biomass 

feedstocks emissions are negligible or de minimis, and that other biomass feedstocks may be 

determined to be negligible or de minimis in the future) would be legally sufficient justification 

for an immediate blanket exemption, and in fact, EPA provides no factual support at all. The 

commenter stated that EPA knows that the weight of the current and thorough science 

overwhelmingly demonstrates that biomass feedstocks are not carbon neutral and do not have 

negligible effects when combusted for energy production, particularly in the near-term 

timeframes that are most meaningful in addressing climate change. The commenter indicated 

that studies in the CFI amply demonstrate that near-term CO2 emissions from stationary sources 

that combust biomass are greater than emissions from sources that combust fossil fuels for the 

same energy output (see docket items EPA-HQ-OAR-2010-0560-0066.2, EPA-HQ-OAR-2010-

0560-0157.1, and EPA-HQ-OAR-2010-0560-0432.1).

Response: EPA disagrees with the commenter’s characterization of EPA’s rationale. As 

explained in the preamble, EPA believes that based on information currently before the Agency, 

including information provided in response to the CFI and the proposal for this rule, that 

emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 

evidence that the deferral to allow for further study is warranted. EPA is using the time under 
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87

this interim deferral to study the science surrounding biogenic CO2 emissions and is developing 

an accounting framework to assist permitting programs and sources. This interim deferral 

represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. EPA will consider the information about the 

carbon lifecycle presented by the commenters, as well as others, as it conducts this study and 

develops the accounting framework prior to developing subsequent regulations establishing 

treatment for specific sources of biogenic emissions of CO2 under the PSD and Title V programs.

Comment: Commenter 0350.1 stated EPA’s authority to create “de minimis” exemptions from 

statutory requirements is extremely limited. The commenter pointed out that the de minimis 

doctrine is reserved for trifling matters, and EPA bears the burden of proving that any such 

departure from the language and the structure (the ‘legislative design’) of the statute truly is a 

trifle or inconsequential, and EPA’s burden is a high one. The commenter quoted the following: 

“Determination[s] 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.”

Alabama Power, 636 F.2d 323, 360 (D.C. Cir. 1979); see also NRDC v. EPA, 966 F.2d 1292, 

1306 (9th Cir. 1992) (rejecting EPA’s attempt to create a de minimis exemption because of lack 

of data showing that regulation would be of “trivial or no value”). 

The commenter noted that the authority for such exemptions is limited to creating a standard

only to the minimum extent necessary “to alleviate ‘severe’ administrative and economic 

burdens by lifting requirements on ‘minuscule’ emission increases.” New York v. EPA, 443 F.3d 

880, 888 (D.C. Cir. 2006) (quoting and citing Alabama Power, 636 F.2d at 405, as basis for 

vacatur of a regulatory provision that would have allowed modified sources with non-de minimis 

emissions increases to avoid statutory control requirements). 

The commenter further noted that the de minimis doctrine does not provide an expansive “ability 

to depart from the statute, but rather a tool to be used in implementing the legislative design ... to 

provide an exemption when the burdens of regulation yield a gain of trivial or no value.” AA LJ 

v. FLRA, 397 F.3d at 962(quoting, EDF v. EPA, 82 F3d 451, 465-66 (D.C. Cir. 1996)); see also 

Public Citizen v. FTC, 869 F.2d 1541, 1556-57 (D.C. Cir. 1989) (doctrine permits exemptions 

when application of statute would have no benefit). Therefore, “the doctrine obviously is not 

available to thwart a statutory command.... Nor is an agency to apply it on a finding merely that 

regulatory costs exceed regulatory benefits.” Public Citizen v. Young, 831 F.2d 1108, 1113 (D.C. 

Cir. 1987) (quoting Alabama Power, 636 F.2d at 360). 

Response: EPA disagrees with the commenter’s characterization of the deferral and EPA’s 

authority to issue the deferral under well-established administrative law doctrines. As explained 

in the preamble, EPA believes that based on information currently before the Agency, including 

information provided in response to the CFI and the proposal for this rule, that emissions from 

certain biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2, or 

may be de minimis but also believes based on the complexity of this evidence that the deferral to 

allow for further study is warranted. EPA is using the time under this interim deferral to study 

the science surrounding biogenic CO2 emissions and is developing an accounting framework to 
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88

assist permitting programs and sources. This interim deferral represents a permissible application 

of well-established administrative law doctrines, necessitated by the scientific uncertainty 

surrounding the accounting of biogenic CO2 emissions, to develop a regulatory scheme that 

implements the CAA consistent with Congressional intent in a step-wise fashion designed to 

minimize administrative burdens and avoid unnecessary regulation of de minimis amounts of air 

pollution. EPA will consider the information about the carbon lifecycle presented by the 

commenter, as well as others, as it conducts this study and develops the accounting framework

prior to developing subsequent regulations establishing treatment for specific sources of biogenic 

emissions of CO2 under the PSD and Title V programs.

Comment: Commenter 0350.1 stated EPA has not met its required burden of proof to support 

the blanket exemption on the ground[s] that the exempted CO2 emissions will be “de minimis” in 

context. The commenter stated EPA has made no effort to show all biogenic CO2 emissions can 

be exempted because they are trivial or inconsequential in context. The commenter noted that 

EPA only states that it “believes” it has the authority to exclude all biogenic CO2 emissions on 

de minimis grounds, provides no justification, and that EPA’s failure to provide the legally 

required support for this rationale demonstrates the unlawfulness of its proposed blanket 

exemption. The commenter indicated that the science and engineering show that burning 

biomass emits more carbon than burning fossil fuels for the same energy output. The commenter 

cited a permit example where 840 lb CO2 per MWH are emitted for a natural gas-fired unit, 

1,885 lb CO2 per MWH are emitted for a coal-fired unit, and 3,050 lb CO2 per MWH are emitted 

for a biomass unit; the biomass unit emits 2 times the coal unit CO2 emissions and almost 4 times 

the natural gas unit CO2 emissions.

The commenter argued that EPA has insufficient scientific justification for a total exemption for

all biomass feedstocks, and in fact, EPA has not even justified a limited exemption for specific 

feedstocks, for example, for residue materials. The commenter noted that EPA has not shown 

that residue materials actually do decompose in a short time period, has not shown that 

instantaneous emissions from biomass combustion are analogous to the emissions that occur over 

the course of a 10 to 15 year decomposition period, and EPA must at the very least make this 

showing to meet its burden to justify an exemption for residue material on the grounds that CO2

emissions is de minimis in context. The commenter went on to state that EPA has not 

demonstrated that residue materials constitute the sole or predominant source of fuel for the 

biomass industry, and if a biomass facility burns other feedstocks than only residues, increased 

forest harvesting and the resulting net forest loss will create CO2 increases beyond those 

measured at the stack. The commenter noted that until the last two or three years, when greater 

scientific scrutiny has been brought to bear on the question, harvesting trees for fuel was widely 

assumed to be “carbon neutral” based on an uncritical acceptance that as long as forests were

allowed to regrow, carbon released by harvesting and combustion would be re-sequestered. The 

commenter indicated that recent science demonstrates that increased forest harvesting to meet 

increased demand for fuel dramatically increases net CO2 emissions above the existing baseline, 

and cited findings from several recent studies, including: the critical importance of taking 

ongoing forest carbon sequestration into account when calculating net carbon emissions from 

biomass energy; the greater carbon emissions per unit energy from biomass than fossil fuels 

combined with the lost forest carbon sequestration associated with additional fuel harvesting 

produce net CO2 emission that greatly exceed fossil fuels; and use of standing trees for bioenergy 
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immediately transfers carbon to the atmosphere, provides relatively smaller GHG benefit from 

displacing coal or gasoline, and increases overall emissions for several decades.

The commenter provided Energy Information Administration (EIA) data showing that in 2009, 

the existing biomass power industry emissions were already a significant source of CO2, at 89 

million tons CO2. The commenter provided EIA CO2 emissions specifically for Maine, where 

total power sector emissions are 5.2 million tons of CO2 (where biomass CO2 emissions are 

counted as zero emissions), and the biomass emissions are another 6.2 million tons CO2 (wood 

and wood-derived fuels only, excludes municipal waste combustion), i.e., biomass CO2

emissions more than double the total. The commenter noted that residues will not meet the new 

biomass demand, and increased forest harvesting will be required, which has been shown to 

significantly increase carbon emissions above fossil fuels. The commenter pointed out that both 

industry sources and the U.S. Forest Service admit that residues and wastes are not sufficient to 

meet biomass demand for energy production. In addition, the commenter noted that industries 

that make wood products have expressed concern that new biomass burning will increase the 

demand for wood. The commenter provided another example for Florida, where 6 new biomass 

plants will need the residues from approximately 1.9 million acres per year (based on estimate of 

4.46 tons per acre) but the entire acreage for forest cutting in Florida is only approximately 0.33 

million acres per year. The commenter stated that these data demonstrate the pressure to 

increase forest harvesting and wood production, even before EPA’s proposed complete 

exemption for biomass facilities is finalized. The commenter suggested that a significant rampup in biomass co-firing at coal plants can be expected in response to the regulatory exemption. 

The commenter reiterated that EPA has not shown that burning forestry wastes for energy 

production would yield only de minimis or trivial net CO2 emissions. The commenter argued 

that burning biomass, even residues, instantly transfers more carbon to the air than burning fossil 

fuels, that decomposition takes time, and that it is not legitimate for EPA to treat CO2 emissions 

from burning waste wood as if they achieve instant parity with emissions that would occur if 

decomposition were occurring instead. The commenter provided a graphic that shows 

significant amounts of decomposing material remains even 10 to 30 years after harvest. 
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The commenter cited a Finnish study that notes forest energy is not as low in emissions as is 

generally assumed; harvesting of wood from forests reduces the quantity of atmospheric carbon 

accumulated in forests; and logging residue would store carbon for a long time if left to rot in the 

forest. The commenter pointed out that EPA’s assertion that burning dead trees killed by 

mountain pine beetles would reduce CO2 emissions is completely unsupported. The commenter 

stated that larger wood masses like standing dead trees take far longer to decompose than 

logging residues, and EPA completely misstates the current scientific understanding of 

decomposition. The commenter pointed out that EPA has not provided a single example where 

combustion of biomass actually reduces GHG emissions. The commenter also cited a recent 

study that indicates the severity of crown fires may be reduced in beetle-killed stands relative to 

undisturbed stands. The commenter stated that EPA has not adequately distinguished its 

proposed treatment of the purported future effect from its longstanding approach to regulating 

criteria pollutants. The commenter went on to note that NOx is regulated at the point and time of 

emissions, and EPA does not ask the question of what the net balance of NOx will be at some

point 10 to 30 years into the future, even though NOx does change after it is emitted. While 

EPA says the situation is unique to GHG regulation, the commenter noted that EPA provides no 

support or justification for this distinction.

Response: EPA disagrees with the commenter’s characterization of the deferral and EPA’s 

authority to issue the deferral under well-established administrative law doctrines. EPA notes 

that it has received other comments taking an opposing view of rationale in support of the 

deferral and the science, which underscores the complexity of the science associated with 

accounting for biogenic CO2 emissions as part of the PSD and Title V permitting programs. As 

explained in the preamble, EPA believes that based on information currently before the Agency, 

including information provided in response to the CFI and the proposal for this rule, that 
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91

emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on this evidence that the 

deferral to allow for further study is warranted. EPA is using the time under this interim deferral 

to study the science surrounding biogenic CO2 emissions and is developing an accounting 

framework to assist permitting programs and sources. This interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis amounts of air pollution. EPA will consider the information about the carbon lifecycle 

presented by the commenter, as well as others, as it conducts this study and develops the 

accounting framework prior to developing subsequent regulations establishing treatment for 

specific sources of biogenic emissions of CO2 under the PSD and Title V programs.

Comment: Commenter 0350.1 stated EPA’s proposal, stripped to its most essential points, is 

entirely made on economic cost/benefit grounds, which cannot justify divergence from statutory 

requirements. The commenter stated that EPA’s blanket exemption proposal is based on a thinly 

disguised policy argument that regulatory costs exceed regulatory benefits, which is never

sufficient, standing alone to justify a de minimis exemption. Public Citizen, 831 F.2d at 1113. 

The commenter indicated that EPA nakedly speculates that the permitting requirements of the 

statute might someday prove financially wasteful, should EPA conclude, following a scientific 

investigation that the Agency has not yet conducted, that some unspecified biomass feedstocks 

might have a negligible carbon footprint. The commenter noted that an industry group asserts 

that its member companies will “obtain substantial benefits” under a biomass CO2 exemption, 

and that biomass energy projects would be at risk of cancellation or delay if the exemption is not 

finalized, but the commenter stated these are purely economic arguments. The commenter cited

additional industry group arguments against regulating the industry, such as reductions in capital 

investment, job losses, and other economic impacts; however, the commenter pointed out that 

even if true, there is no indication that these arguments are any more true for the biomass 

industry than for any other industry that emits CO2 and is subject to EPA regulations. The 

commenter stated such arguments cannot justify a departure from statutory requirements, on de 

minimis grounds. Public Citizen, 831 F.2d at 1113.

Response: EPA disagrees with the commenter’s view that this action is based purely on policy 

grounds or costs and is unsupported by the law or science. As EPA explained in more detail in 

the responses to the commenter’s other comments, as well as in the preamble, this interim 

deferral represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA in a step-wise fashion designed to 

minimize administrative burdens and avoid unnecessary regulation of de minimis amounts of air 

pollution. As explained in the preamble, EPA believes that based on information currently before 

the Agency, including information provided in response to the CFI and the proposal for this rule, 

that emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on this evidence that the 

deferral to allow for further study is warranted. EPA is using the time under this interim deferral 

to study the science surrounding biogenic CO2 emissions and is developing an accounting 

framework to assist permitting programs and sources. EPA will consider the information about 
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92

the carbon lifecycle presented by the commenter, as well as others, as it conducts this study and 

develops the accounting framework prior to developing subsequent regulations establishing 

treatment for specific sources of biogenic emissions of CO2 under the PSD and Title V programs.

Comment: Commenter 0118.1 declared that to justify the deferral, EPA asserts that biogenic 

CO2 emissions that would result from the deferral of regulation would be de minimis. However, 

the commenter contended that scientific materials already in the record from related proceedings 

in EPA rulemaking concerning these emissions already demonstrate that the assertion is false.

Commenter 0118.1 also noted that permanently making biogenic CO2 sources at or above 

Tailoring Rule thresholds subject to PSD and Title V would not result in trivial gain and would 

in fact result in substantial gains and that sources that are clearly de minimis would not be 

regulated. Additionally, the commenter stressed that the available science in the Tailoring Rule 

record and need to mitigate climate change support any added administrative burdens the 

alternative may cause.

Commenter 0118.1 stated that applying, for three years, PSD and Title V requirements to all 

facilities that have the potential for net biogenic CO2 at or above Tailoring Rule thresholds 

would result in significant overall regulatory gain and would be important for mitigating climate 

change.

Response: EPA disagrees with the commenter’s characterization of the deferral and EPA’s 

authority to issue the deferral under well-established administrative law doctrines. EPA notes 

that it has received other comments taking an opposing view of rationale in support of the 

deferral and the science, which underscores the complexity of the science associated with 

accounting for biogenic CO2 emissions as part of the PSD and Title V permitting programs. As 

explained in the preamble, EPA believes that based on information currently before the Agency, 

including information provided in response to the CFI and the proposal for this rule, that 

emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on this evidence that the 

deferral to allow for further study is warranted. EPA is using the time under this interim deferral 

to study the science surrounding biogenic CO2 emissions and is developing an accounting 

framework to assist permitting programs and sources. This interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis amounts of air pollution. EPA will consider the information about the carbon lifecycle 

presented by the commenter, as well as others, as it conducts this study and develops the 

accounting framework prior to developing subsequent regulations establishing treatment for 

specific sources of biogenic emissions of CO2 under the PSD and Title V programs.

Comment: Commenter 0078.1 stated EPA has justified the deferral based on the concept of de 

minimis emissions but believed the Agency’s conclusion falls somewhat short of linking the 

soundness of the carbon balance in the U.S that fully supports the proposed action – the reality is 

clearly much better than de minimis. The commenter noted EPA is fully justified in deciding 

biogenic CO2 emissions should be excluded.
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Response: EPA appreciates with the commenter’s support for the deferral. EPA is using the 

time under this interim deferral to study the science surrounding biogenic CO2 emissions and is 

developing an accounting framework to assist permitting programs and sources. This interim 

deferral represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution.

11.6 De minimis Authority Applies

Comment: Commenter 0082.1 stated that EPA has the authority to invoke the de minimis 

doctrine and exempt biogenic CO2 emissions from permitting because the LULUCF inventory 

indicates sequestration capacity at the national scale is greater than demand for forest products. 

Commenters 0063.1, 0086.1, and 0095.1 agreed that EPA has the authority to apply the de 

minimis doctrine as long as a reasonable explanation has been provided. Commenters 0063.1 

and 0095.1 further explained that because there is evidence that biogenic CO2 emissions do not 

result in any net increases in atmospheric CO2 at the national scale, these emissions do not share 

the “endangering” characteristic that EPA attributes to other GHG and supported EPA’s 

authority to exempt biogenic emissions from PSD and Title V programs. Commenter 0095.1 

stated that exempting these emissions would be consistent with the objective of striking and 

maintaining the balance Congress sought between economic growth and environmental 

preservation.

Response: EPA appreciates with the commenters views on the de minimis rationale and will 

keep them in mind as it conducts the scientific study, develops an accounting methodology, and 

undertakes subsequent rulemakings on these issues. EPA notes that the issue of an 

“endangerment” finding for biogenic CO2 emissions is beyond the scope of this action. As 

explained in more detail in the “Endangerment and Cause or Contribute Findings for Greenhouse 

Gases Under Section 202(a) of the Clean Air Act” (74 FR 66496), and the Light Duty Vehicle 

Rule, the Agency has found that air pollution in the form of elevated concentrations of a group of 

six individual GHG in the atmosphere, including CO2, may reasonably be anticipated to 

endanger both public health and public welfare and that emissions from new motor vehicles of 

an air pollutant composed of this same group of GHG contributes to this air pollution. In the 

Light Duty Vehicle Rule EPA set standards applicable to emissions of this air pollutant.

11.7 Potential for Some Biomass Feedstocks to Have a De minimis Impact 

on Carbon Levels in the Atmosphere

Comment: Commenter 0062.1 supported EPA’s statement that some biomass feedstocks have a 

de minimis impact and commenter 0104.1 articulated that special provisions may be warranted 

for some biogenic fuel stocks which may be de minimis and divided biomass into three colorcoded categories with respect to potential for de minimis impacts when used as fuel:

• The commenter described “green” biomass as responsibly-grown perennials that might 

well qualify as carbon neutral over a one year accounting period, consistent with the 

current PSD legal framework. This category may also include some crops deemed neutral 
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over a three year period. The commenter stated that such “green” feedstocks may be 

eligible for the de minimis doctrine.

• The commenter described “red” biomass as fuel stocks such as whole trees that are not 

carbon neutral in the near-term time scale relevant to curtailing global warming; such 

feedstocks are not eligible for the de minimis doctrine.

• The commenter construed the proposal as asserting that further study might support a de 

minimis conclusion for the “gray” biomass, but stated that EPA must support this 

conclusion with a record based on available data. 

Response: EPA agrees with the commenters’ view that some biomass feedstocks may have de 

minimis impact on atmospheric levels of CO2. EPA notes that it has received other comments 

taking an opposing view of the science, which underscores the complexity of the science 

associated with accounting for biogenic CO2 emissions as part of the PSD and Title V permitting 

programs. As explained in the preamble, EPA believes that based on information currently 

before the Agency, including information provided in response to the CFI and the proposal for 

this rule, that emissions from certain biomass feedstocks may have a neglible impact on 

atmospheric concentrations of CO2, or may be de minimis but also believes based on the 

complexity of this evidence that the deferral to allow for further study is warranted. EPA is using 

the time under this interim deferral to study the science surrounding biogenic CO2 emissions and 

is developing an accounting framework to assist permitting programs and sources. This interim 

deferral represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. EPA will consider the information about the 

carbon lifecycle presented by the commenters, as well as others, as it conducts this study and 

develops the accounting framework prior to developing subsequent regulations establishing 

treatment for specific sources of biogenic emissions of CO2 under the PSD and Title V programs.

Comment: Commenter 0350.1 stated that EPA has not justified even a limited exemption for 

particular biomass feedstocks. The commenter stated the Act requires EPA to consider all CO2

emissions when determining PSD and Title V applicability, without creating exemptions based 

on fuel characteristics or sources that emit the pollutant; the statute also mandates case-by-case 

BACT determinations. See 42 U.S.C. §7479(3) (defining BACT as a case-by-case 

determination, based in part on the application of clean fuels). The commenter noted that EPA 

would have to provide sufficient scientific and legal justification for each exempted feedstock.

The commenter further indicated that any such exemption would have to be drawn narrowly 

enough to demonstrate that no facility-specific life-cycle inquiry is necessary for the particular 

feedstock. The commenter stated that the burden to justify even a limited exemption proposed in 

the future would be very high.

Response: EPA disagrees with the commenter’s characterization of the deferral and EPA’s 

authority to issue the deferral under well-established administrative law doctrines. As explained 

in the preamble, EPA believes that based on information currently before the Agency, including 

information provided in response to the CFI and the proposal for this rule, that emissions from 

certain biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2, or 

may be de minimis but also believes based on the complexity of this evidence that the deferral to 
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95

allow for further study is warranted. EPA is using the time under this interim deferral to study 

the science surrounding biogenic CO2 emissions and is developing an accounting framework to 

assist permitting programs and sources. This interim deferral represents a permissible application 

of well-established administrative law doctrines, necessitated by the scientific uncertainty

surrounding the accounting of biogenic CO2 emissions, to develop a regulatory scheme that 

implements the CAA consistent with Congressional intent in a step-wise fashion designed to 

minimize administrative burdens and avoid unnecessary regulation of de minimis amounts of air 

pollution. Subsequent regulations to establish treatment of biogenic emissions under the PSD 

and Title V programs are beyond the scope of this action.

Comment: Commenter 0084.1 stated that because biogenic sources of CO2 emissions, other 

than combustion of biomass, have not been the focus of recent CAA changes and guidance, 

generally accepted emission factors have not been developed and reviewed. The commenter 

declared that this will cause enormous difficulties when trying to determine whether emissions 

from biogenic sources will trigger PSD/Title V when added to sources of CO2 from combustion 

of fossil fuels or biomass fuels. The commenter further stated that there are currently no AP-42 

emission factors available for those types of biogenic sources and that many of those sources are 

fugitive in nature. Commenter 0084.1 asserted that unless EPA and then the non-EPA permitting 

authorities revise the current PSD/Title V rules to permanently recognize the carbon neutrality of

most, if not all, biogenic emissions, the lack of emission estimation techniques will result in great 

regulatory uncertainty and difficulty for affected sources. Those difficulties, the commenter 

stated will have to be a major factor in EPA's future estimates of paperwork in Information

Collection Requests to OMB pursuant to the Paperwork Reduction Act.

Response: EPA appreciates the commenter’s views. The comment underscores the complexity 

of the science associated with accounting for biogenic CO2 emissions as part of the PSD and 

Title V permitting programs. As discussed in the preamble, EPA is using the time under this 

interim deferral to study the science surrounding biogenic CO2 emissions and is developing an 

accounting framework to assist permitting programs and sources. 

Comment: Commenters 0071.1 and 0332 believe the prevailing science acknowledges 

significant carbon benefits of energy produced using renewable biomass. The commenter 

pointed out that biomass energy production avoided the GHG emissions associated with the 

production of fossil fuels, and it avoids the biogenic greenhouse gas emissions (mainly methane) 

of the various alternative disposal fates of biomass residues, replacing them with the lower 

potency greenhouse gas emissions of energy production. Commenter 0071.1 also stated that 

biomass combustion actually promotes further forest growth by providing landowners with an 

incentive to maintain forests instead of pursuing other land use options that sequester less 

carbon.

Response: EPA appreciates the commenters’ views. The comment underscores the complexity 

of the science associated with accounting for biogenic CO2 emissions as part of the PSD and 

Title V permitting programs. As discussed in the preamble, EPA is using the time under this 

interim deferral to study the science surrounding biogenic CO2 emissions and is developing an 

accounting framework to assist permitting programs and sources.
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Comment: Commenter 0093.1 cited a white paper on alternative fates for biomass. The 

commenter noted that according to the white paper, of all of the alternative fates for biomass the 

use of fuels for energy production leads to lower levels of biogenic greenhouse gases over time 

than the alternative disposal of the resources. The commenter stated that biogenic emissions from 

energy production using all of these kinds of biomass resources, which include biomass diverted 

from landfill disposal, biomass diverted from open burning, and biomass that results from forest 

treatment operations (thinning) designed to reduce the risks of destructive wildfires and insect 

and disease outbreaks, should be granted exemptions from the Tailoring Rule based on a finding 

of de minimis impact.

Response: EPA appreciates the commenter’s views. The comment underscores the complexity 

of the science associated with accounting for biogenic CO2 emissions as part of the PSD and 

Title V permitting programs. As discussed in the preamble, EPA is using the time under this 

interim deferral to study the science surrounding biogenic CO2 emissions and is developing an 

accounting framework to assist permitting programs and sources. This interim deferral represents 

a permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis amounts of air pollution. 

Comment: Commenter 0089.1 stated that sufficient data exist for permanent exemptions for 

certain biomass feedstocks and fuels. The commenter recommends that EPA permanently 

exempt those biomass fuels that had been clearly demonstrated to be carbon neutral and apply 

the deferral rule only to those biomass fuels that EPA needs to resolve the uncertainty as to the 

impact on the carbon cycle.

Response: EPA appreciates the commenter’s views. As explained in the preamble, EPA 

believes that based on information currently before the Agency, including information provided 

in response to the CFI and the proposal for this rule, that emissions from certain biomass 

feedstocks may have a neglible impact on atmospheric concentrations of CO2, or may be de 

minimis but also believes based on the complexity of this evidence that the deferral to allow for 

further study is warranted. EPA is using the time under this interim deferral to study the science 

surrounding biogenic CO2 emissions and is developing an accounting framework to assist 

permitting programs and sources. This interim deferral represents a permissible application of 

well-established administrative law doctrines, necessitated by the scientific uncertainty 

surrounding the accounting of biogenic CO2 emissions, to develop a regulatory scheme that 

implements the CAA consistent with Congressional intent in a step-wise fashion designed to 

minimize administrative burdens and avoid unnecessary regulation of de minimis amounts of air 

pollution. Subsequent regulations to establish treatment of biogenic emissions under the PSD 

and Title V programs are beyond the scope of this action.

11.8 Administrative Burdens of Permitting Projects Involving Biogenic 

CO2

Comment: Commenter 0104.1 argued that EPA has not demonstrated that permitting major 

facilities which are sources of biogenic emissions will be burdensome since they have already 
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been accounted for under Step 2 of the Tailoring Rule. Furthermore, the commenter requests that 

EPA provide information on the degree of burden from permitting that any state will incur and 

what types of feedstocks the facilities within those states will use. The commenter provided 

some history on the tiered system in the Tailoring Rule and requests that EPA explain why the 

tiered system is an excessive burden which justifies the potential for categorical exclusion of 

biogenic CO2 emissions despite the scientific evidence surrounding the impacts of certain 

feedstocks. However, the commenter did anticipate that accounting for the complexity of which 

feedstocks should be considered de minimis (e.g., highly productive perennial grasses, MSW and 

wastewater biogas generation, etc.) and which should be subject to permitting (e.g., feedstocks 

with unknown lifecycle impacts or those which have clear impacts such as whole trees) will add 

some necessary and prudent burdens. Commenter 0045 argued that the deferral will eliminate 

administrative burdens that could otherwise encumber the biomass industry and that the deferral 

will facilitate construction of countless bioenergy facilities at tremendous costs in terms of state 

and federal bioenergy subsidies. Commenter 0045 stated that such projects will cause substantial 

losses of American forests, and that such projects will be completed at the expense of our 

planet’s climate and public health.

Response: EPA disagrees with the commenters’ views on the burdens associated with the 

accounting of biogenic emissions of CO2. As explained in the preamble, EPA believes that 

based on information currently before the Agency, including information provided in response to 

the CFI and the proposal for this rule, that emissions from certain biomass feedstocks may have a 

neglible impact on atmospheric concentrations of CO2, or may be de minimis but also believes 

based on the complexity of this evidence that the deferral to allow for further study is warranted. 

EPA is using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

This interim deferral, necessitated by the scientific uncertainty surrounding the accounting of 

biogenic CO2 emissions, provides EPA with time to develop a regulatory scheme that 

implements the CAA consistent with Congressional intent in a step-wise fashion designed to 

minimize administrative burdens and avoid unnecessary regulation of de minimis amounts of air 

pollution. EPA will consider the information about the carbon lifecycle presented by the 

commenters, as well as others, as it conducts this study and develops the accounting framework

prior to developing subsequent regulations establishing treatment for specific sources of biogenic 

emissions of CO2 under the PSD and Title V programs. 

Comment: Commenter 0145.1 stated that the proposal sets permitting authorities up for the 

insurmountable task of trying to determine lifecycle emissions for an extremely broad 

classification of biogenic materials, and that instead of reducing the regulatory burden of GHG 

regulations the proposal increases burdens associated with properly permitting bioenergy 

facilities. Commenter 0145.1 characterized the proposed deferral as “exempting an entire 

industry from regulation legally mandated by Massachusetts v. EPA” at the expense of public 

health and the environment. 

Response: EPA disagrees with the commenter’s views that the deferral increases the regulatory 

burden. As explained in the preamble, EPA believes that based on information currently before 

the Agency, including information provided in response to the CFI and the proposal for this rule, 

that emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 
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98

evidence that the deferral to allow for further study is warranted. EPA is using the time under 

this interim deferral to study the science surrounding biogenic CO2 emissions and is developing 

an accounting framework to assist permitting programs and sources. This interim deferral, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

provides EPA with time to develop a regulatory scheme that implements the CAA consistent 

with Congressional intent in a step-wise fashion designed to minimize administrative burdens 

and avoid unnecessary regulation of de minimis amounts of air pollution. EPA will consider the 

information about the carbon lifecycle presented by the commenters, as well as others, as it 

conducts this study and develops the accounting framework prior to developing subsequent 

regulations establishing treatment for specific sources of biogenic emissions of CO2 under the 

PSD and Title V programs. 

Comment: Commenter 0053 stated that municipal wastewater management agencies warrant 

special treatment because they manage waste for the benefit of people and the environment, not 

for profit. Such public services would be significantly and unproductively burdened by the 

Tailoring Rule if biogenic emissions are not exempted. Similarly, Commenter 0116.1 further 

added that a small portion is non-biogenic (e.g., from combustion of non-recyclable plastic) and 

under EPA’s proposal larger WTE facilities will remain subject to the costly and burdensome 

PSD-Title V permitting regimen, regardless of the biogenic ruling. Imposing PSD-Title V 

regulation for WTE facilities’ insignificant non-biogenic CO2 emissions will only serve to 

discourage WTE and encourage land-filling, resulting in higher GHG emissions. 

Commenter 0116.1 provides several references in support of the environmental and GHGmitigating benefits of WTE over land-filling.

Response: EPA appreciates the commenters’ views. As explained in the preamble, EPA 

believes that based on information currently before the Agency, including information provided 

in response to the CFI and the proposal for this rule, that emissions from certain biomass 

feedstocks may have a neglible impact on atmospheric concentrations of CO2, or may be de 

minimis but also believes based on the complexity of this evidence that the deferral to allow for 

further study is warranted. EPA is using the time under this interim deferral to study the science 

surrounding biogenic CO2 emissions and is developing an accounting framework to assist 

permitting programs and sources. This interim deferral, necessitated by the scientific uncertainty 

surrounding the accounting of biogenic CO2 emissions, provides EPA with time to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis amounts of air pollution. Subsequent regulations to establish treatment of specific 

sources of biogenic emissions under the PSD and Title V programs are beyond the scope of this 

action.

Comment: Commenter 0070.1 suggested that biomass deferral, and then permanent exemption 

should be expanded to CO2e because the CH4 and N2O emissions from biomass combustion 

typically account for a small fraction of the GWP. Inclusion of in the deferral would promote the 

construction of biomass facilities and compliance with state voluntary or mandatory renewable 

energy standards. Another option is for EPA to invoke the de minimis doctrine to CH4 and N2O 

from biomass combustion. Commenter 0032 stated that small facilities which use wood 

byproducts for combined heating and power would incur unreasonably high costs to meet the 
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permitting requirements under the original rule. The commenter articulated that administrative 

burdens may result in lost jobs or the diversion of by-products to waste streams and significantly 

impact the forest products industry, particularly in rural areas with vulnerable economies. 

Commenter 0062.1 argued that EPA has not adequately assessed the additional number of PSD 

permits or the added complexity in permit development that will be entailed by permitting 

biogenic emissions. The commenter expects that inclusion will greatly increase the complexity 

of PSD review by requiring lifecycle analyses and interpretation of the GHG implications 

associated with new projects. Commenter 0062.1 projected that the addition of GHG

(particularly biogenic CO2 emissions) will subject many more landfill projects (e.g., expansions, 

control devices, new LFGTE projects etc.) to PSD permitting in part because there is no 

available control device for CO2. Additionally, commenter 0062.1 stated that if biogenic CO2

emissions from landfill gas projects are regulated under the PSD program, the facilities would 

need carbon credits to offset pollution control devices required by the NSPS program which 

reduces methane and other organic compounds to CO2. Therefore, EPA would require carbon 

credits for the operation of a system which has been internationally recognized as a means of 

generating legitimate, tradable carbon credits, and Commenter 0062.1 argued that requiring 

permits for landfill generation of biogenic CO2 could thwart the development of new landfill gas 

to energy projects even though the projects can be beneficial by converting methane to CO2. 

Commenters 0074.1, 0087.1 and 0091.1 stated that any environmental effect of biomass 

combustion on atmospheric concentrations of CO2 is a beneficial one. The commenters 

supported EPA’s assessment that placing the burdens of those studies on local permitting 

authorities that already face permitting backlogs from existing and new air quality standards 

would be unmanageable, especially during a time when budgets and workforces have been cut. 

Further, commenter 0087.1 stated that BACT analyses required to determine the net impact of 

biomass projects would impose even more time-consuming and novel considerations on state 

PSD permitting programs above a beyond current challenges completing BACT determinations 

for CO2 from fossil fuels. Commenter 0102.1 articulated that an extension of PSD permitting 

requirements to biogenic CO2 emission sources would not be only burdensome to state and local 

permitting agencies, but would also affect Minnesota’s commitment to renewable energy through 

the Next Generation Energy Act.

Response: EPA disagrees with the commenters seeking expansion of the deferral to CO2e. 

While non-CO2 GHG are produced when biomass is combusted, the level of emissions and 

resulting impact on atmospheric concentrations of these gases are primarily related to the 

feedstock handling and combustion conditions at the specific plant rather than to the source of 

the feedstocks. We finalized this rule as proposed and included only biogenic CO2 emissions for 

this reason, and we note further that emissions of non-CO2 GHG are typically a small proportion 

of the total GHG emissions from combustion of biologically based material. Since the non-CO2

GHGs are so small relative to CO2, the deferral of biogenic CO2 emissions will ensure the 

biomass combustion projects will likely not meet the applicability thresholds based on their CH4

and N2O emissions alone.

EPA appreciates the views of the commenters who expressed concern about the burdens faced by 

permitting authorities to account for biogenic emissions of CO2 and the impact permitting delays 

will have on industries that use biomass. EPA is using the time under this interim deferral to 

study the science surrounding accounting for biogenic CO2 emissions in order to develop an

accounting framework to assist permitting programs and sources. Subsequent regulations to 
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establish treatment of specific sources of biogenic emissions under the PSD and Title V 

programs are beyond the scope of this action.

Comment: Commenter 0070.1 suggested that biomass deferral, and then permanent exemption 

should apply to CO2 and CO2e. CO2e of these other greenhouses gases are typically a small 

fraction of the total carbon dioxide emitted during biomass combustion. Inclusion of CH4 and 

N2O in the deferral would promote the construction of biomass facilities and compliance with 

state voluntary or mandatory renewable energy standards. To the extent EPA chooses not to do 

this, as an alternative, CH4 and N2O should be deemed de minimis for purposes of the threshold 

determination, so as not to undermine EPA's stated purpose for proposing the deferral. 

Response: EPA disagrees with the commenters seeking expansion of the deferral to CO2e. 

While non-CO2 GHG are produced when biomass is combusted, the level of emissions and 

resulting impact on atmospheric concentrations of these gases are primarily related to the 

feedstock handling and combustion conditions at the specific plant rather than to the source of 

the feedstocks. We finalized this rule as proposed and included only biogenic CO2 emissions for 

this reason, and we agree with the commenter that emissions of non-CO2 GHG are typically a 

small proportion of the total GHG emissions from combustion of biologically based material. 

Since the non-CO2 GHGs are so small relative to CO2, the deferral of biogenic CO2 emissions 

will ensure the biomass combustion projects will likely not meet the applicability thresholds 

based on their CH4 and N2O emissions alone. Subsequent regulations to establish treatment of 

specific sources of biogenic emissions under the PSD and Title V programs are beyond the scope 

of this action.

Comment: Commenter 0084.1 stated that under PSD permitting guidelines whether a project is 

“new” depends on rules that often take the form of “grandfather” exemptions, and whether a 

project is “major” depends, of course, on the complex “algebra” of “before and after” emissions, 

as well as netting. The commenter expressed that it appears when EPA takes its final action, it 

plans to remove CO2 emissions from that applicability “algebra” immediately upon the effective 

date of the final action. Therefore, the commenter contended, a project could be “major” for PSD 

or Title V purpose on one day and “minor” the next. The commenter stressed that it is critical for 

avoiding wasted effort, unnecessary delay, and sound planning that EPA time its final action and 

the effective date of that action so as to occur well before July 1, or at least as of July 1. The 

commenter is concerned that EPA may have difficulty accomplishing this because of the volume 

of comments on the present proposal or competing priorities. As a result, the commenter noted 

that the EPA must make sure to avoid what could be a de facto construction moratorium if EP A 

is delayed or does not time the effective date well.

Response: EPA agrees with the commenter that accounting for biogenic emissions, as part of 

determining applicability of PSD and Title V programs, is complex. As discussed in the 

preamble, EPA is using the time under this interim deferral to study the science surrounding 

accounting for biogenic CO2 emissions in order to develop an accounting framework to assist 

permitting programs and sources. EPA believes that the full three year deferral period is 

necessary to complete this work and to develop any subsequent regulations to establish treatment 

of the PSD and Title V programs to specific biogenic sources of CO2 emissions.
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Comment: Commenter 0118.1 noted that with the deferral EPA seeks to avoid the absurd result 

of an excessive permitting burden; however, the commenter contended that the deferral creates 

the even more absurd result of allowing major biogenic CO2 sources to escape regulation 

permanently and irreversibly if they utilize the three year window. Commenter 0118.1 expressed 

that this is a direct contradiction to the legal requirement for EPA to regulate CO2 emissions. The 

commenter stated that the deferral can be expected to result in a stampede of hastily-filed

applications, made by corporations and other entities in an effort to avoid CO2 regulation, which 

the commenter contended will result in regulatory burden. Commenter 0118.1 also noted that the 

deferral will create an unfair competitive advantage for those entities that construct facilities 

under the loophole, over those entities that construct later, when emissions are regulated. The 

commenter believes the deferral is illegal.

Response: EPA disagrees with the commenter’s characterization of the deferral and EPA’s 

authority to issue the deferral under well-established administrative law doctrines. EPA notes 

that it has received other comments taking an opposing view of rationale in support of the 

deferral and the science, which underscores the complexity of the science associated with 

accounting for biogenic CO2 emissions as part of the PSD and Title V permitting programs. As 

explained in the preamble, EPA believes that based on information currently before the Agency, 

including information provided in response to the CFI and the proposal for this rule, that 

emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 

evidence that the deferral to allow for further study is warranted. EPA is using the time under 

this interim deferral to study the science surrounding biogenic CO2 emissions and is developing 

an accounting framework to assist permitting programs and sources. This interim deferral 

represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. Subsequent regulations to establish treatment 

of specific sources of biogenic emissions under the PSD and Title V programs, based on the 

results of the study and development of the accounting framework, are beyond the scope of this 

action.

Comment: Commenter 0129.1 stressed that EPA has not adequately addressed the regulatory 

burdens associated with permitting biogenic emissions under the PSD and Title V programs 

citing EPA’s technical support document for the Tailoring Rule. The commenter noted that the 

land fill section evaluation of technical support document did not include the number of new 

facilities impacted nor did it account for biogenic emissions in the analysis. Thus, the commenter 

stated, the administrative burdens for including biogenic emissions have clearly not been

evaluated based on EPA’s technical support, and concluded that the inclusion of biogenic 

emissions will increase the number of permits and create an unnecessary regulatory burden even 

when there is no climate change impact.

Response: EPA conducted the regulatory burden analysis for the Tailoring Rule proposal 

utilizing the Information Collection Requests for PSD and Title V Programs, along with earlier 

analyses performed and data gathered to develop emission thresholds for the proposed and final 

GHG Mandatory Reporting Rule. During the public comment period, some commenters 
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requested that, in calculations of emissions for determining applicability of PSD and Title V, 

EPA exempt emissions from biogenic activities or biomass combustion or oxidation activities. 

Revisions were made to the burden analysis based on comments received during proposal and 

updates to key assumptions. However, commenters did not provide information to demonstrate

that an overwhelming permitting burden would still exist, thereby justifying an exclusion for

biomass sources.

EPA acknowledges the commenter’s concern that the administrative burdens for including 

biogenic emissions have not been evaluated. At that time, EPA had not examined burdens with 

respect to specific source categories impacted by the rule and thus had not analyzed the 

administrative burden of permitting projects that specifically involve biogenic CO2 emissions 

taking account of the threshold-based approach. Thus, the Agency indicated its intent to seek 

further comment on how to address emissions of biogenic CO2 under the PSD and Title V 

programs through a future action. After soliciting views from the public through the CFI and 

granting NAFO’s petition for reconsideration, EPA initiated a detailed examination of the 

science associated with biogenic CO2 emissions from stationary sources is conducted, including 

engaging with federal partners, technical experts, and an independent scientific panel to consider 

technical issues. Based on the feedback from the scientific and technical review, EPA will then 

undertake rulemaking to determine how biogenic CO2 emissions should be treated and accounted 

for in PSD and Title V permitting.

11.9 Applying the Tailoring Rule Rationale for Biomass

Comment: Commenter 0118.1 noted that deferral of the Tailoring Rule is itself an “absurd 

result,” an outcome the EPA set out to avoid. The commenter expressed that a better alternative 

needs to be chosen.

Response: EPA disagrees with the commenter’s characterization of the Tailoring Rule and 

considers reconsideration of it outside the scope of the action. This interim deferral, necessitated 

by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, provides 

EPA with time to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent in a step-wise fashion designed to minimize administrative burdens and 

avoid unnecessary regulation of de minimis sources of air pollution. 

Comment: Commenter 0129.1 encouraged EPA to finalize the deferral no later than July 1, 

2011 which is a critical deadline for the PSD Tailoring rule implementation.

Response: EPA agrees with the commenter.

Comment: Commenter 0064.1 stated that the extension of PSD permitting to CO2 emissions 

from biomass sources is counter to EPA’s own technical and policy findings and programs based 

on current science. The Tailoring Rule is the first rule in the world to regulate emissions of GHG 

from biomass to the same degree as emissions from fossil fuels. It is contradictory for the EPA to 

recognize biomass as a potential tool for Best Available Control Technology for emissions 

reduction while simultaneously treating biomass emissions as equal to fossil fuel emissions 

within the permitting requirements.
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Response: EPA disagrees with the comment. As explained in the preamble, EPA believes 

based on information currently before the Agency, including information provided in response to 

the CFI and the proposal for this rule, that emissions from certain biomass feedstocks have a 

neglible impact on atmospheric concentrations of CO2, or may be de minimis but also believes 

based on the complexity of this evidence that the deferral to allow for further study is warranted. 

EPA is using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

This interim deferral represents a permissible application of well-established administrative law 

doctrines, necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2

emissions, to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent in a step-wise fashion designed to minimize administrative burdens and 

avoid unnecessary regulation of de minimis amounts of air pollution. Subsequent regulations to 

establish treatment of specific sources of biogenic emissions under the PSD and Title V 

programs, based on the results of the study and development of the accounting framework, are 

beyond the scope of this action.

Comment: Commenter 0071.1 stated that EPA should use the method it has already employed 

in the Tailoring Rule—adopting an “enforceable commitment” to carrying through the study and 

rulemaking. 40 CFR §§ 50.22, 70.12, 71.13, 75 Fed. Reg. at 31,607-08. Thus EPA would 

commit in its regulations to complete the review and new rules within three years. That course 

would utilize an already-existing EPA policy regarding ongoing regulatory review and be more 

legally consistent with the parallel Tailoring Rule. 

Response: EPA disagrees with the comment. As explained in the preamble, EPA believes 

based on information currently before the Agency, including information provided in response to 

the CFI and the proposal for this rule, that emissions from certain biomass feedstocks have a 

neglible impact on atmospheric concentrations of CO2, or may be de minimis but also believes 

based on the complexity of this evidence that the deferral to allow for further study is warranted. 

EPA is using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

This interim deferral represents a permissible application of well-established administrative law 

doctrines, necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2

emissions, to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent in a step-wise fashion designed to minimize administrative burdens and 

avoid unnecessary regulation of de minimis amounts of air pollution. Subsequent regulations to 

establish treatment of specific sources of biogenic emissions under the PSD and Title V 

programs, based on the results of the study and development of the accounting framework, are 

beyond the scope of this action.

Comment: Commenter 0082.1 articulated that the application of the PSD and Title V programs 

to stationary source GHG is ill-advised, whether with or without the Agency’s temporary 

modification of applicability thresholds. The commenter stated that EPA compounded the 

problems when it reversed national and international precedent and policy by requiring facilities 

to include their biogenic CO2 emissions in the temporary applicability thresholds established in 

the final PSD Tailoring Rule.
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Response: EPA disagrees with the comment. EPA notes it did consider treatment of biogenic 

emissions during the development of the Tailoring Rule but determined the information before 

the Agency at that time did not provide sufficient basis to exclude emissions of CO2 from 

biogenic sources in determining permitting applicability provisions at that time. In the final 

Tailoring Rule we indicated that the decision not to provide this type of an exclusion at that time 

did not foreclose EPA’s ability to either (1) provide this type of exclusion at a later time with 

additional information about overwhelming permitting burdens due to biomass sources, or (2) 

provide another type of exclusion or other treatment based on some other rationale. Although we 

did not take a final position, we noted that some commenters’ observations about a different 

treatment of biomass combustion warranted further exploration as a possible rationale.

Therefore, although we did not establish a permanent exclusion from PSD or Title V 

applicability based on specific characteristics of biogenic CO2, we indicated our intent to seek 

further comment on how we might address emissions of biogenic CO2 under the PSD and Title V 

programs through a future action. This action fulfills that intent, and enables the Agency to 

make its final decision on the treatment of these emissions based on a thorough analysis of 

applicable science and policy concerns. 

Comment: Commenter 0089.1 asked for a clarification of the actual effect of the deferral on 

new facilities or modifications completed during the three year deferral that would have 

otherwise triggered GHG BACT requirements without the deferral rule. The commenter stated 

that the language in the proposal created some uncertainty as to whether the deferral fully 

exempts new and modified sources permitted during the three year period or only delays 

applicability.

Response: EPA notes that the issue of subsequent applicability of the PSD and Title V 

programs to facilities that may be permitted during the deferral period (also referred to as 

“grandfathering”) is beyond the scope of this action and an is addressed in more detail in Section

II.C of the preamble. 

Comment: Commenter 0350.1 stated that EPA has not justified a blanket exemption for 

biogenic CO2 on “administrative necessity” grounds. The commenter noted EPA’s reliance in 

part on the same rationale used to justify the Tailoring Rule phase-in approach, namely the 

administrative necessity and absurd results doctrines; however EPA does not come close to 

justifying proposed exemption for biogenic CO2 on either of those grounds. In the Tailoring 

Rule, the commenter noted that EPA conducted the appropriate 3-step process (included 

streamlining administration, justifiably concluding that remaining administrative tasks are 

impossible for the Agency, and phasing in or adjusting the requirements so they are 

administrable); calculated the number of permits, the work hours, and the cost required under the 

statute’s threshold emission levels and demonstrated the efforts exceeded the current program by 

orders of magnitude; and then calculated the same impacts for 8 alternative approaches and 

discussed each at length. The commenter stated the availability of the administrative necessity 

doctrine is limited to cases involving proven impossibility and cited the supporting cases. The 

commenter stated that the evidentiary bar for an Agency’s claims of administrative necessity is 

extremely high, and such claims must be rejected in all but impossibly burdensome 

circumstances.
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Response: EPA disagrees with the commenter’s characterization of the deferral and the view 

that this action is unsupported by the law. As EPA explained in the responses to the 

commenter’s other comments, as well as in the preamble, this interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA in a step-wise fashion designed to minimize 

administrative burdens and avoid unnecessary regulation of de minimis amounts of air pollution. 

As amply demonstrated in the record and in the preamble, the complexity and uncertainty of the 

science surrounding biogenic emissions of CO2 from various sources and their role in the carbon 

cycle, as well as the lack of established accounting methodologies, create significant challenges 

for permitting authorities and sources already burdened by their obligations under the PSD and 

Title V programs to regulate GHG. EPA believes that based on information currently before the 

Agency, including information provided in response to the CFI and the proposal for this rule, 

that emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 

evidence that the deferral to allow for further study is warranted. EPA is using the time under 

this interim deferral to study the science surrounding biogenic CO2 emissions and to develop an 

accounting framework to assist permitting programs and sources. 

Comment: Commenter 0350.1 stated EPA provides no evidence or analysis supporting 

assertions of extensive workload or administrative impossibility in its exemption proposal. The 

commenter stated EPA attempts a short-cut to piggy-back on the Tailoring Rule’s meticulous 

analysis but this short-cut is fatally flawed. The commenter stated the Tailoring Rule already 

calculated the annual administrative burdens arising from all GHG PSD permits, including the 

very PSD permits at issue here, and concluded that, at the new applicability thresholds, permits 

for all sources emitting CO2 could indeed be processed. The commenter noted that EPA is 

missing a quantification of what the workload consists of, how many biomass feedstock sources 

will need permits over what time period, additional work hours needed to issue the permits, what 

costs would be incurred, what delays would result, and why it would be impossible for EPA to 

process the required permits. The commenter indicated EPA presents no further evidence in this 

proposal demonstrating that permitting biogenic feedstocks sources as required by the statute 

would increase permitting burden, beyond the evidence it presented to justify the Tailoring 

Rule’s new thresholds. The commenter further noted that absent any additional evidence of 

impossibility, EPA cannot now simply ignore its previous reasoning, see Sierra Club v. Martin, 

168 F.3d 1, 4 (11th Cir. 1999) (holding agency must follow regulations and procedures it has 

previously established), and its sudden departure from its own pronouncements less than a year 

earlier casts serious doubt on validity of changed analyses. See also, Mt. Graham Red Squirrel v. 

Madigan, 954 F.2d 1441, 1457 (9th Cir. 1992) (granting no deference to agency expertise when 

its position has fluctuated). Even assuming that permitting for sources using biogenic feedstock 

did cause an “extensive additional workload,” the commenter noted that such a circumstance 

falls far short of meeting the requirements in case law to show real impossibility to justify 

divergence from statutory mandates. The commenter stated EPA makes no attempt to quantify 

that additional burden as applied to currently prevailing permitting case loads or to prove that 

impossible administrative conditions currently prevail.

Response: EPA disagrees with the commenter’s characterization of the deferral and the view 

that this action is unsupported by the law. As EPA explained in the responses to the 
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commenter’s other comments, as well as in the preamble, this interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA in a step-wise fashion designed to minimize 

administrative burdens and avoid unnecessary regulation of de minimis amounts of air pollution. 

As amply demonstrated in the record and in the preamble, the complexity and uncertainty of the 

science surrounding biogenic emissions of CO2 from various sources and their role in the carbon 

cycle, as well as the lack of established accounting methodologies, create significant challenges 

for permitting authorities and sources already burdened by their obligations under the PSD and 

Title V programs to regulate GHG. EPA believes that based on information currently before the 

Agency, including information provided in response to the CFI and the proposal for this rule, 

that emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 

evidence that the deferral to allow for further study is warranted. EPA is using the time under 

this interim deferral to study the science surrounding biogenic CO2 emissions and to develop an 

accounting framework to assist permitting programs and sources. 

Comment: Commenter 0350.1 stated EPA cannot manufacture “administrative necessity”

where it does not exist. The commenter noted that EPA manufactures complexities in 

determining the net carbon impacts of various biomass fuels, from what EPA asserts is the need 

to reconcile facility-based and land-based sequestration accounting systems, which is a need not 

cognizable under the statute nor adequately supported by the Agency. The commenter stated 

EPA’s complexity argument is a red herring, in that counting these emissions from sources is a 

straightforward process that is exactly the same regardless of whether the sources use biogenic or 

fossil fuel feedstock. The commenter went on to cite that the CAA demands that “[n]o major 

emitting facility on which construction is commenced may be constructed . . . unless (1) a permit 

has been issued for such proposed facility . . . setting forth emission limitations for such facility 

which conform to the requirements of this part.” 42 U.S.C. § 7475(a)(1). The commenter stated 

that because sources are “major” based on the amount of CO2 they emit, not based on the 

lifecycle CO2 analysis of the feedstock they use, lifecycle analysis complexities do not in any 

way affect the determination of whether a permit is required. The commenter pointed out that 

EPA can and must make that determination, and can and must issue permits if emission 

thresholds are exceeded regardless of lifecycle questions. The commenter supported EPA’s 

decision to engage in lifecycle analyses that compare overall CO2 emissions among various 

energy sources as part of the 5-step, top-down BACT emissions limit determination process; 

however, the fact that the full resolution of all uncertainties concerning this inquiry may take 

some time is neither novel to how PSD permitting has been administered for decades, nor an 

impediment to permit issuance. The BACT process is the proper venue for addressing remaining 

lifecycle analysis uncertainties based on the currently existing state of knowledge, just as the 

case-by-case BACT inquiry relating to the “best available control technologies” and fuel sources, 

42 U.S.C. § 7479(a)(3), functions well despite the fact that the “best” technology or “clean fuel”

may currently be neither available nor known. The commenter noted that the BACT process 

itself contains the answer to the difficulties EPA cites. The commenter went on to say that EPA’s 

unsubstantiated fear that such analysis might prove “complex” in no way excuses the complete 

exclusion of CO2 pollution sources from mandatory PSD permitting requirements.
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The commenter stated EPA’s attempt to rely on administrative necessity completely reverses the 

applicable burdens of proof under the doctrine. The commenter indicated that EPA does not 

even attempt to provide proofs of impossibility here or to demonstrate that its proposed 

exemption is consistent with or protective of congressional intent, and indeed, it cannot, in light 

of its admission that it simply does not know whether particular biogenic feedstocks indeed meet 

the newly created permitting off ramp of carbon neutrality. That, EPA says, can be determined 

only after further study.

Response: EPA disagrees with the commenter’s characterization of the deferral and the view 

that this action is unsupported by the law. As EPA explained in the responses to the 

commenter’s other comments, as well as in the preamble, this interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA in a step-wise fashion designed to minimize 

administrative burdens and avoid unnecessary regulation of de minimis amounts of air pollution. 

As amply demonstrated in the record and in the preamble, the complexity and uncertainty of the 

science surrounding biogenic emissions of CO2 from various sources and their role in the carbon 

cycle, as well as the lack of established accounting methodologies, create significant challenges 

for permitting authorities and sources already burdened by their obligations under the PSD and 

Title V programs to regulate GHG. EPA believes that based on information currently before the 

Agency, including information provided in response to the CFI and the proposal for this rule, 

that emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on the complexity of this 

evidence that the deferral to allow for further study is warranted. EPA is using the time under 

this interim deferral to study the science surrounding biogenic CO2 emissions and to develop an 

accounting framework to assist permitting programs and sources. EPA appreciates the 

commenter’s view on BACT and notes that the interim BACT guidance EPA released in March 

2011 is beyond the scope of this action.

Comment: Commenter 0350.1 stated EPA has not demonstrated that regulating sources of 

biogenic CO2 would create “absurd results.” The commenter argued that it is the permitting 

exemption that would cause an absurd result rather than the statutorily mandated regulation of 

biogenic CO2 emissions, because the exemption will lead to increased, not decreased, near-term 

CO2 emissions. The commenter stated that EPA fails to show that requiring permitting for these 

sources and discouraging use of biomass is an absurd result, or an undesirable outcome from the 

perspective of environmental protection, in that it would stall or avoid the rush to biomass and 

avoid increased near-term CO2 emissions. The commenter stated EPA’s proposal relieves all 

sources that emit biogenic CO2 emissions of all permitting requirements for these emissions, no 

matter how many millions of tons of CO2 are emitted, for 3 full years, even though EPA has 

before it a great deal of thorough, recent scientific study showing that all biomass is not equal, 

and some feedstocks exceed even coal’s CO2 emissions, whether evaluated at the stack or on a 

lifecycle basis. The commenter noted that the entire Proposed Rule is premised on the fact that 

highly significant differences in lifecycle CO2 emissions among biomass feedstocks do exist, and 

yet, EPA offers blanket relief from regulation for all. The commenter further stated that the 

exemption will result in unregulated plants that unless and until major modifications are later

undertaken, will never become subject to permitting requirements.
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Response: EPA disagrees with the commenter’s characterization of the deferral and the view 

that this action is unsupported by the law. As EPA explained in the responses to the 

commenter’s other comments, as well as in the preamble, this interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA in a step-wise fashion designed to minimize 

administrative burdens and avoid unnecessary regulation of de minimis sources of air pollution. 

EPA notes that the issue of subsequent applicability of the PSD and Title V programs to facilities 

that may be permitted during the deferral period (also referred to as “grandfathering”) is beyond 

the scope of this action and will be addressed in any rulemakings subsequent to the conclusion of 

the scientific study and development of the accounting methodologies. 

11.10 Tailoring Rule Phase-in Approach is Inappropriate

Comment: Commenter 0087.1 argued that EPA has sufficient information at this time to 

conclude that the combustion of some biomass feedstocks has a negligible impact on the net 

carbon cycle and that any gain by regulating that combustion would be trivial. The commenter 

requested that EPA delete the clause “prior to [DATE 3 YEARS AFTER THE EFFECTIVE 

DATE OF THE FINAL DEFERRAL RULE].” The commenter stated that if EPA feels a need 

to impose a deadline on itself to do so, that should be in the form of an enforceable commitment 

similar to the deadline for addressing sources smaller than the Tailoring Rule thresholds.

Response: EPA appreciates the commenter’s views but disagrees that it has sufficient 

information at the present time to establish treatment under the PSD and Title V programs for 

specific biomass fuel stocks. As explained in the preamble, EPA believes based on information 

currently before the Agency, including information provided in response to the CFI and the 

proposal for this rule, that emissions from certain biomass feedstocks may have a neglible impact 

on atmospheric concentrations of CO2, or may be de minimis but also believes based on the 

complexity of this evidence that the deferral to allow for further study is warranted. EPA is 

using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

Subsequent regulations to establish treatment of specific sources of biogenic emissions under the 

PSD and Title V programs, based on the results of the study and development of the accounting 

framework, are beyond the scope of this action.

11.11 Supports Tailoring Rule Phase-in Approach

Comment: Commenter 0083.1 supported the “one-step-at-a-time” doctrine and notes that it also 

applies well to EPA’s decision to delay regulation of biogenic CO2 emissions under the PSD and 

Title V programs. With the Tailoring Rule, EPA has already chosen not to regulate GHG under 

PSD and Title V in “one fell regulatory swoop” (75 Fed. Reg. 31544), and there appears to be no 

reason that same deliberate approach, allowing EPA time to develop the information it needs to 

make appropriate policy decisions, could not be applied to support the deferral.

Response: EPA agrees with the commenter that the deferral is also supported under the “onestep-at-a-time” doctrine. In effect, this deferral is a step back from the Tailoring Rule’s 

approach, but the decision to defer the applicability of PSD and Title V to biogenic CO2
11.0 Rationale and Legal Justification for Interim Deferral

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emissions is nonetheless supported, in part, on the same rationale as EPA used to justify the 

Tailoring Rule's phase-in approach. This action constitutes a refinement of the approach EPA 

has taken to regulate GHG emissions from stationary sources through a phased-in approach, 

based on an evolving understanding of the complexities and nuances associated with biogenic 

emissions.

11.12 Subjecting Biogenic CO2 Emissions to Permitting may be 

Counterproductive because it could Discourage Utilization of the Biomass 

Feedstock as Fuel

Comment: Commenter 0051.1 stated that an onerous regulatory structure could discourage 

future investments in bioenergy.

Response: EPA appreciates the commenter’s views. EPA is using the time under this interim 

deferral to study the science surrounding biogenic CO2 emissions and is developing an 

accounting framework to assist permitting programs and sources. This interim deferral represents 

a permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA consistent with Congressional intent in a step-wise 

fashion designed to minimize administrative burdens and avoid unnecessary regulation of de 

minimis amounts of air pollution. Subsequent regulations to establish treatment of specific 

sources of biogenic emissions under the PSD and Title V programs, based on the results of the 

study and development of the accounting framework, are beyond the scope of this action.

Comment: Commenter 0042.1 cited a study by the Green Power Institute that over the pasts 30 

years in California, biomass energy production has avoided the GHG emissions associated with 

the production of fossil fuels and avoided the biogenic greenhouse gas emissions (mainly 

methane) of the various alternative disposal fates of biomass residues, replacing them with the 

lower potency greenhouse gas emissions of energy production. Thus, the commenter noted, 

science acknowledges the carbon benefits of biomass energy. 

Response: EPA appreciates the commenter’s views, which underscore the complexity of the 

science associated with the accounting of biogenic emissions, including issues associated with 

the role of forest residues in the carbon cycle. 

Comment: Multiple commenters (0064.1 and 0071.1) stated that regulating biogenic carbon the 

same as fossil fuels has several unintended consequences, including encouraging fossil fuel use, 

increased greenhouse gas emissions from National Forests, and lost U.S. manufacturing jobs.1

 

1 The Unintended Consequences of the EPA Tailoring Rule. Bruce Lippke and Dr. Elaine Oneil. 2010. 

Commenter 0064.1 attached an article that stated that the greatest threat to deforestation is the 

conversion of private forests to more economically competitive, non-forest uses. Biomass energy 

http://www.corrim.org/pubs/reports/2010/biomass_vs_fossil/BiomassVSFossilEmissionsNov2010.pdf. See also A 

Developing Bioenergy Market and Its Implications on Forests and Forest Products Markets in the United States. Dr. 

Mike Clutter et. al. 2010. http://nafoalliance.org/wp-content/uploads/NAFO-Executive-Summary-Clutter-Et-AlFinal.pdf
11.0 Rationale and Legal Justification for Interim Deferral

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can be an important new market to replace other declining markets and add economic value to 

private forest ownership. 

Commenter 0140.1 stated that additional consequences of regulating biogenic carbon the same as 

fossil fuels are the negative effect on electric utilities and other environmental programs, such as 

state-based RES requirements and the development of domestic offsets based on biomass, 

increased consumer costs, and could result in a competitive disadvantage or stranded investments 

for those companies that already have invested in biomass facilities, relying on existing 

regulations that treat such emissions as carbon neutral.

Response: EPA appreciates the views of the commenters but notes the commenter’s views on 

the economics of the biomass industry are beyond the scope of this action. Subsequent 

regulations to establish treatment of specific sources of biogenic emissions under the PSD and 

Title V programs, based on the results of the study and development of the accounting 

framework, are beyond the scope of this action. EPA notes that a variety of Federal and State 

policies have recognized that some types of biomass can be part of national strategy to reduce 

dependence on fossil fuels and to reduce emissions of GHG.

Comment: Commenter 0140.1 stated that an advantage of using biomass to generate electricity 

is that it can reduce other emissions. When co-fired with coal, biomass may lower emissions of 

criteria pollutants (or relevant criteria pollutant precursors) such as sulfur dioxide (SO2), 

particulate matter (PM) and NOx.

Response: EPA appreciates the views of the commenter and notes that treatment of non-CO2

emissions from biomass are not the subject of this action.

Comment: Commenters 0015.1, 0089.1, 0090.1, and 0135.1 supported EPA’s position that 

subjecting certain CO2 biogenic emissions to permitting may be counterproductive because it 

could discourage utilization of the biomass feedstock as fuel.

Response: EPA appreciates the views of the commenters but notes the commenter’s views on 

the economics of the biomass industry are beyond the scope of this action. Subsequent 

regulations to establish treatment of specific sources of biogenic emissions under the PSD and 

Title V programs, based on the results of the study and development of the accounting 

framework, are beyond the scope of this action. 

Comment: Several commenters (0053.1, 0059.1, 0062.1, 0080.1 and 0117.1) stated that 

requiring permits for waste- and wastewater-derived biogas combustion would discourage 

utilization of landfill and wastewater energy sources. Commenters 0053.1 and 0117.1 stated that 

regulation of biogenic emissions from combustion of biogas serves as a disincentive for use of a 

green renewable energy resource which converts methane to CO2 and displaces fossil fuel use. 

Commenter 0015.1 stated that EPA should finalize the deferral to avoid discouraging the use of 

fuels that would decrease dependence on fossil fuels and dependence on imported fuels. 

Commenter 0080.1 described the uniqueness of waste as a renewable resource and reviews the 

results of an EPA Landfill Methane Outreach Program (LMOP) program study which identified 

the energy benefits of avoided GHG emissions at existing LFGTE facilities as well as the 

benefits of new projects at existing landfills for converting methane to energy and displacing 
11.0 Rationale and Legal Justification for Interim Deferral

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more fossil fuel. The commenter also provided a chart illustrating each state’s RPS which 

involve utilizing waste for energy. Commenters 0053.1 and 0070.1 stated that waste-derived 

biogas can serve as a reliable green renewable energy resource that complements other 

intermittent energy resources such as wind and solar. Commenters 0080.1 and 0117.1 provided 

information from CARB’s fuel standards showing biogas as a low carbon intensity fuel source 

and quoted EPA’s statements on the energy potential of sludge; they also provided international 

references on the energy potential of waste- and wastewater-derived biogas. Commenters 0059.1 

and 0080.1 further supported the importance of maintaining positive incentives for promoting 

such WTE projects. Commenters 0059.1 and 0062.1 also stated that many local governments 

have invested in waste-based energy and stated that burdening these facilities with additional 

regulations requiring carbon neutrality would have significant impacts on local governments 

using waste-based energy as a source of income. Commenter 0117.1 requested that EPA use the 

deferral period to investigate the benefits of waste- and biosolids-derived fuels, and the 

commenter indicates that such wastes contain up to 10 times the energy needed for treatment. 

The commenter also encouraged EPA to consider the possibility that requiring WTE projects to 

go through major source permitting might compel facilities to choose traditional fossil-fuel 

burning treatments.

Response: EPA appreciates the views of the commenter and notes that treatment of non-CO2

emissions from biomass and incentives for the biomass industry are beyond scope of this action. 

Subsequent regulations to establish treatment of specific sources of biogenic emissions under the 

PSD and Title V programs, based on the results of the study and development of the accounting 

framework, are beyond the scope of this action. EPA notes that a variety of Federal and State 

policies have recognized that some types of biomass can be part of national strategy to reduce 

dependence on fossil fuels and to reduce emissions of GHG.

Comment: Commenters 0146, 0052.1, 0095.1 and 0125.1 argued that any attempt to regulate 

CO2 emissions from biomass combustion would disadvantage U.S. manufacturers and 

combustion facilities in both domestic and international markets by increasing administrative 

time and costs as well as negatively misrepresenting the environmental and sustainability 

characteristics of biogenic products as compared to international conventions that do not require 

reporting or permitting biogenic CO2 emissions. Similarly, commenter 0086.1 stated that a 

failure to exempt biofuels production and combustion from CO2 permitting would have 

devastating impacts on the existing bioenergy industry and would significantly threaten further 

development of renewable energy sources and economic expansion in rural areas. Commenter 

0146 supported this statement by referencing a 2010 study which found that regulating biogenic 

carbon would cost between 12,000-28,000 renewable energy jobs, $18 billion fewer dollars of 

capital investment in renewable energy, and over 5,384 fewer megawatts of renewable electricity 

generation in up to 30 states. Commenter 0087.1 stated that the uncertainty of a new permitting 

program requiring case-by-case life-cycle analyses in order to construct biogenic energy projects 

introduces delays and risks to capital that favor more traditional permitting approaches such as 

fossil fuels. Additionally, a PSD permitting approach that gives no recognition to the carbon 

cycle attributes of biomass discourages or even prevents use of biomass in lieu of fossil fuel in a 

new facility or for a repowering project, frustrating the purposes of the CAA as well as national 

energy policy. Similarly, commenter 0095.1 stated that EPA should not discourage use of 

biomass as an energy source for generating electricity and states that EPA should develop an 

appropriate methodology for assessing emissions and sinks to ensure the selection and use of 
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fuels that can help limit GHG emissions. Commenter 0023C stated that the Tailoring Rule 

frustrates the President’s agenda and states that EPA must clearly recognize the benefits of forest 

carbon in air quality policy to remove uncertainty and to advance the President’s renewable 

energy priorities. Commenter 0077.1 stated that investment to bring biomass energy sources into 

wider use should not be penalized by rules that would create a greater regulatory burden. 

Similarly, commenter 0063.1 stated that exempting biogenic emissions would allow new 

biomass combustion facilities to be constructed or existing sources modified without increasing 

GHG concentrations, whereas imposing PSD regulation on emissions from biomass combustion 

would discourage the use of biomass fuels and be at odds with Section 160(3) of the CAA. The 

commenter further requested that an appropriate methodology at the national scale be developed 

to investigate sources and sinks of biogenic carbon. Commenter 0077.1 stated that deferral 

allows EPA to engage in further study and to propose amended rules, if needed, based on sound 

science. 

Response: EPA appreciates the views of the commenters but notes the commenter’s views on 

the economics of the biomass industry are beyond the scope of this action. As explained in the 

preamble, EPA believes based on information currently before the Agency, including 

information provided in response to the CFI and the proposal for this rule, that emissions from 

certain biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2, or 

may be de minimis but also believes based on the complexity of this evidence that the deferral to 

allow for further study is warranted. EPA is using the time under this interim deferral to study 

the science surrounding biogenic CO2 emissions and is developing an accounting framework to 

assist permitting programs and sources. Subsequent regulations to establish treatment of specific 

sources of biogenic emissions under the PSD and Title V programs, based on the results of the 

study and development of the accounting framework, are beyond the scope of this action.

Comment: Commenter 0072.1 stated that regulating biomass will lead to American 

manufacturing job loss, since international competitors follow IPCC and do not regulate biogenic 

emissions. Commenter 0078.1 stated their products compete in global markets with countries 

that recognize net neutrality of biogenic CO2 emissions.

Response: EPA appreciates the views of the commenters but notes the commenter’s views on 

the economics of the biomass industry are beyond the scope of this action.

Comment: Commenter 0086.1 stated increased use of biomass and biofuels as an energy source 

in lieu of fossil fuels also addresses urbanization air quality concerns by promoting rural 

economies and preserving agricultural lands, because with the added incentive of using 

agricultural feedstocks for biofuel production, agricultural lands are more likely to stay 

agricultural lands, and EPA’s National Inventory has consistently shown net sequestration of 

cropland that remained cropland since 1990. The commenter concluded that concerns of 

increased biofuel production resulting in loss of forestland are wholly misplaced and without 

empirical support, and stated that promotion of agricultural lands furthers the goals of the Act.

Response: EPA appreciates the commenter’s views, which underscore the complexity of the 

science associated with the accounting of biogenic emissions, including issues associated with 

the roles of agricultural and forestland in carbon sequestration as part of the carbon cycle. 
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Comment: Commenter 0093.1 stated that the risks of a three-year deferral in order to get the 

science right are negligible, while the risks of seriously harming the industry in its formative 

stages, and preventing it from delivering the greenhouse gas benefits it is capable of are large.

Response: EPA appreciates the commenter’s views. As explained in the preamble, EPA 

believes based on information currently before the Agency, including information provided in 

response to the CFI and the proposal for this rule, that emissions from certain biomass feedstocks 

may have a neglible impact on atmospheric concentrations of CO2, or may be de minimis but 

also believes based on the complexity of this evidence that the deferral to allow for further study 

is warranted. EPA is using the time under this interim deferral to study the science surrounding 

biogenic CO2 emissions and is developing an accounting framework to assist permitting 

programs and sources.

Comment: Commenter 0111.1 stated that displacing finite fossil heating fuels with locallysourced biomass is one of the most efficient and economical pathways to energy independence, 

rural economic growth, and promotion of forest health.

Response: EPA considers the commenter’s views about the role of locally sourced biomass to 

be beyond the scope of this action.

11.13 EPA Should Not Promote Biomass Use

Comment: Commenters 0104.1 and 0023G stated that the potential for wood demand is 

significant and that only a tiny minority of the facilities now proposed intend to use agricultural 

residues or purpose-grown energy crops for fuel. Commenter 0104.1 quoted a data source 

indicating about 117 new direct-fired biomass facilities will use wood in addition to new projects 

to co-fire wood. Additionally, the commenter reviewed U.S. Forest Service data to show that 

wood residues are too scarce to meet emerging “energy wood” needs and provides example 

calculations and testimonies indicating a trend toward unsustainable forest harvests. The 

commenter argued that although looking to woody biomass to meet renewable energy goals is 

tempting, safeguarding U.S. sequestration capacity and reducing carbon emissions from fossil 

fuel sources should be instrumental in solving the climate change problem. Commenters 0110, 

0115.1, and 0137.1, 0166 further stated that the deferral period will spur companies to rapidly 

build or convert facilities before the three-year period expires. Similarly, commenters 0145.1 

and 0030 argued that the proposed regulation provides biomass combustion power plants with 

undeserved preferential treatment and incentives while potentially driving up health care costs 

due to pollution. Commenter 0030 further stated that biomass combustion already accounts for 

about half of US renewable generation and competes directly for the same subsidies that also 

support non-polluting renewables such as wind and solar. Commenter 0145.1 stated that any CO2

and climate benefits from closing or cleaning up coal plants are neutralized by the current 

construction of new biomass combustion power facilities that emit more CO2 per megawatt than 

coal power. The commenter provided examples and estimates of the wood-burning electricity, 

biomass pellet, and coal conversion plants in the process of planning and permitting, as well as 

rough estimates of the biogenic CO2 that the facilities will emit during their lifetime. 

Furthermore, the commenter listed the multiple subsidies, tax credits, renewable energy credits 

and incentives that biomass plants receive as a renewable energy generator without having to 

account for the potential environmental and public health impacts of biogenic CO2 emissions. 
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Commenter 0145.1 also discussed the low job creation (20-40 permanent jobs over the facility 

lifetime) associated with biomass power projects, especially when compared to the grants and 

incentives provided to each facility and the possible competition it places on other wooddependent industries with high job creation potential. The commenter cited several corporations 

which indicate that they will face competition from the increased biomass combustion industry 

and contrasts several other industries that promote energy efficiency and renewable energy with 

a higher job creation potential. Commenters (0023E, 0030, and 0166) also stated that unqualified 

exemption of biomass will incent numerous uncontrolled GHG sources and use of fuels worse 

for the climate (in GHG emissions per megawatt produced) than coal, all while eliminating 

proven sinks. Commenters 0023E and 0023G stated that American forests cannot keep pace 

with the rapid expansion of biomass combustion projects being planned. Commenter 0023G 

opposed deferral and rejects the justification that EPA needs to come up with a biogenic 

accounting system, because there will be no federal oversight of the feedstocks permitted and 

used during the deferral period. Furthermore, the commenter argued that weak maximum 

achievable control technology (MACT) standards for biomass boilers allow them to emit as 

much or more hazardous air pollution as coal plants. Commenter 0030 supported this statement 

by further adding that the hazardous air pollution will escalate as the number of biomass 

facilities increase. Commenter 0045 stated that in addition to the potential for whole tree 

clearing, fallen organic material on the forest floor is integral to the health of the forest and to 

species in the forest, and that the urgency to reduce GHG emissions is of utmost importance to 

avoid the impacts of climate change.

Response: EPA considers the commenters’ views about economic incentives for the biomass 

industry beyond the scope of this action. As explained in the preamble, EPA believes that based 

on information currently before the Agency, including information provided in response to the 

CFI and the proposal for this rule, that emissions from certain biomass feedstocks may have a 

neglible impact on atmospheric concentrations of CO2, or may be de minimis but also believes 

based on the complexity of this evidence that the deferral to allow for further study is warranted. 

EPA is using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

This interim deferral represents a permissible application of well-established administrative law 

doctrines, necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2

emissions, to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent in a step-wise fashion designed to minimize administrative burdens and 

avoid unnecessary regulation of de minimis amounts of air pollution. Subsequent regulations to 

establish treatment of specific sources of biogenic emissions under the PSD and Title V 

programs, based on the results of the study and development of the accounting framework, are 

beyond the scope of this action.

Comment: Commenter 0350.1 stated EPA has not met its burden of proof to support the 

blanket exemption on grounds that regulating biogenic CO2 will be of trivial or inconsequential 

value. The commenter cited industry statements that the exemption will encourage a biomass 

industry boom by creating significant incentives to choose uncontrolled biomass sources rather 

than other truly renewable or low-carbon energy sources. The commenter stated EPA provides 

nothing in the record to show or support that there would not be any, or trivial, increased CO2

emissions resulting from the growing biomass industry that results from a blanket exemption for 
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all biogenic CO2, and does not show that encouraging the biomass boom through the proposed 

exemption will yield de minimis impacts. The commenter stated that EPA cannot make this 

showing because, far from de minimis, the blanket exemption will yield significant increases in 

uncontrolled biogenic CO2 emissions. The commenter stated that EPA’s identification of some 

unspecified subset of biomass feedstocks with purportedly de minimis climate impacts cannot 

justify a blanket exemption for every form of biomass, EPA assertions that feedstocks are 

“negligible” are unsupported, and nowhere does EPA describe the particular types of feedstocks 

it believes have de minimis climate impacts, in that it provides only a few unsupported examples. 

The commenter noted that EPA does not even attempt to explain why converting residue 

feedstocks immediately to atmospheric CO2 is “negligible” or de minimis. The commenter stated 

that short-term climate impacts of combusting such feedstocks may be highly significant given 

that climate studies show that global CO2 emissions must peak within the next decade and then 

decline significantly thereafter to avoid catastrophic climate change. In that context, the 

commenter stated EPA has not met its burden.

The commenter stated that EPA’s assertion that regulation of all biomass emissions can be 

deferred because scientific study might reveal the existence of other “negligible” feedstocks is 

even more egregious. The commenter noted that mere speculation and conjecture about what 

might occur after further scientific review is not sufficient justification for a present blanket 

exemption from statutory requirements.

Response: EPA disagrees with the commenter that the deferral is not supported by the 

complexity of the science surrounding biogenic sources of CO2 emissions or well-established 

administrative law doctrines. EPA notes that it has received other comments taking an opposing 

view of rationale in support of the deferral and the science, which underscores the complexity of 

the science associated with accounting for biogenic CO2 emissions as part of the PSD and Title 

V permitting programs. As explained in the preamble, EPA believes that based on information 

currently before the Agency, including information provided in response to the CFI and the 

proposal for this rule, that emissions from certain biomass feedstocks may have a neglible impact 

on atmospheric concentrations of CO2, or may be de minimis but also believes based on the 

complexity of this evidence that the deferral to allow for further study is warranted. EPA is using 

the time under this interim deferral to study the science surrounding biogenic CO2 emissions and 

is developing an accounting framework to assist permitting programs and sources. This interim 

deferral represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 

to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. Subsequent regulations to establish treatment 

of specific sources of biogenic emissions under the PSD and Title V programs, based on the 

results of the study and development of the accounting framework, are beyond the scope of this 

action.

Comment: Commenter 0350.1 stated EPA’s proposed blanket exemption for all biomass 

sources is arbitrary and capricious. The commenter stated EPA’s proposal would have the effect 

of increasing near-term emissions of CO2, and the Agency should be well aware that is the case. 

A decision to finalize the proposed blanket exemption, even on a temporary basis, under these 

circumstances is a textbook case of arbitrary and capricious decision making, and cited Motor 
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Vehicle Mfrs Ass’n v. State Farm Mutual Auto. Ins. Co., 463 U.S. 29(1983)(there must be a 

rational relationship between the facts at hand and the choice made). The commenter stated that 

a decision to finalize an exemption as proposed on the basis asserted would be contrary to the 

evidence before the Agency, would ignore important aspects of how to craft programs that can 

yield significant CO2 emissions reductions in the near term, and would certainly constitute a 

“clear error in judgment.” Id. citing Bowman Transportation, Inc. v. Arkansas-Best Freight 

System, Inc., 419 U.S. 281, 285 (1974); Citizens to Preserve Overton Park v. Volpe, 401 U.S. 

402, 416 (1971).

Response: EPA disagrees with the commenter’s characterization of the deferral and the view 

that this action is unsupported by the law or science. As EPA explained in the responses to the 

commenter’s other comments, as well as in the preamble, this interim deferral represents a 

permissible application of well-established administrative law doctrines, necessitated by the 

scientific uncertainty surrounding the accounting of biogenic CO2 emissions, to develop a 

regulatory scheme that implements the CAA in a step-wise fashion designed to minimize 

administrative burdens and avoid unnecessary regulation of de minimis sources of air pollution.

As explained in the preamble, EPA believes that based on information currently before the 

Agency, including information provided in response to the CFI and the proposal for this rule, 

that emissions from certain biomass feedstocks may have a neglible impact on atmospheric 

concentrations of CO2, or may be de minimis but also believes based on this evidence that the 

deferral to allow for further study is warranted. EPA is using the time under this interim deferral 

to study the science surrounding biogenic CO2 emissions and is developing an accounting 

framework to assist permitting programs and sources. Subsequent regulations to establish 

treatment of specific sources of biogenic emissions under the PSD and Title V programs, based 

on the results of the study and development of the accounting framework, are beyond the scope 

of this action.

Comment: Commenter 0350.1 stated that because EPA’s proposal prejudges the outcome of its 

study, it is internally contradictory and therefore arbitrary and capricious. The commenter stated 

EPA’s proposal is fundamentally contradictory, as EPA states that determining the lifecycle of 

CO2 impacts of biomass combustion is so complex and burdensome that a three-year hiatus is 

necessary to allow study, but at the same time announces its conclusions, without providing 

scientific support, that certain feedstocks either have “negligible” climate impacts or “clearly 

reduce CO2 emissions.” The commenter indicated EPA cannot conclude on the basis of 

information presented in the Proposal that emission from combustion of these feedstocks are 

“negligible”, de minimis, or otherwise not worth regulating. The commenter stated the Agency’s 

conclusion that biomass feedstocks which decompose over 10 to 15 years have negligible 

climate impacts is not supported by science. The commenter cited a recent study that determined 

energy production from logging residues results in significant CO2 emissions over a short 

timeframe, and these emissions are overlooked by accounting methods that follow IPCC 

guidance and the Kyoto Protocol, and are in fact an order of magnitude larger than the harvest, 

processing, and transport emissions that are included in analyses. The commenter noted the 

critical time for CO2 emissions reductions is in the near term, a point which EPA’s assertions 

ignore, as they are based on some net effect of assumed re-sequestration in the future. The 

commenter stated emissions from combustion of feedstocks are not “negligible” and will actually 

increase global CO2 concentration during the precise period when the science indicates those 

concentrations must peak and begin to decline. The commenter stated that even if a particular 
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biomass feedstock could be considered “carbon neutral” over a longer period of time, it cannot 

be consider carbon neutral now or during the proposed deferral period.

Response: EPA disagrees with the commenter’s view that this action is unsupported by the law 

or science. As EPA explained in responses to the commenter’s other comments, as well as in the 

preamble, this interim deferral represents a permissible application of well-established 

administrative law doctrines, necessitated by the scientific uncertainty surrounding the 

accounting of biogenic CO2 emissions, to develop a regulatory scheme that implements the CAA

in a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. As explained in the preamble, EPA believes 

that based on information currently before the Agency, including information provided in 

response to the CFI and the proposal for this rule, that emissions from certain biomass feedstocks 

may have a neglible impact on atmospheric concentrations of CO2, or may be de minimis but 

also believes based on this evidence that the deferral to allow for further study is warranted. EPA 

is using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

Subsequent regulations to establish treatment of specific sources of biogenic emissions under the 

PSD and Title V programs, based on the results of the study and development of the accounting 

framework, are beyond the scope of this action.

Comment: Commenter 0048.1 stated biomass burners and burning the biomass in garbage is 

dirtier than coal and produces more CO2.

Response: EPA appreciates the commenter’s views. The comment underscores the complexity 

of the science associated with accounting for biogenic CO2 emissions as part of the PSD and 

Title V permitting programs.

Comment: Commenter 0119.1 expressed skepticism that biomass is a net carbon sink. The 

commenter asserted that the best available science indicates that bioenergy is a net carbon 

emitter and in some scenarios a more significant carbon emitter than existing energy technology 

(see EPA-HQ-OAR-2011-0083-0119.1 for studies). However, the commenter noted that 

typically science does not look at carbon impact of forest management which may be the biggest 

point of release.

Commenter 0119.1 also noted that the increased competition of the bioenergy industry in the 

South’s forests could challenge paper producers striving to meet goals for improvement in forest 

management and undermine the movement in the US wood and paper market to improve fiber 

sourcing.

Commenter 0019.1 noted that US forests are more useful as forests than as a source of fuel. The 

commenter further expressed that policies should focus on increasing forest protection, 

restoration of degraded forests, and improvement of industrial logging techniques, all of which 

would be a better strategy to solving the climate crisis. The commenter concluded that energy 

policy and investment should focus on conservation and efficiency and alternatives like wind and 

solar.

Response: EPA appreciates the views of the commenter and will keep them in mind as it 

develops subsequent regulations to establish treatment of specific sources of biogenic emissions 
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under the PSD and Title V programs, based on the results of the study and development of the 

accounting framework. The commenter’s views in support of other renewable energy sources is 

beyond the scope of this action.

Comment: Commenters 0065.1 and 0143.1 noted that a three-year exemption would allow for 

the development of large biomass combustion facilities, which appears to lack legal or scientific 

merit, endangers public health, and is fiscally irresponsible. Commenter 0143.1 further stated 

that allowing biomass facilities to be constructed, without regard to their CO2 emissions, will 

seriously undermine the intent of the Tailoring Rule.

Commenter 0143.1 contended that permitting the construction of large biomass combustion 

operations is fiscally irresponsible. The commenter provided examples of grants from the 

American Recovery and Investment Act of 2009 (ARRA) and loans from the DOE and U.S. 

Department of Agriculture (USDA) which are underwritten by taxpayers who envision their 

funds being used to support clean, “green” renewable energy. Finally, the commenter claimed 

that biomass combustion will continue to be favored if it is exempted from permitting, setting 

our nation on course to a future of polluted air, ill health, degraded lands and increased 

greenhouse gas emissions.

Commenter 0065.1 stated that an increase in large unregulated facilities and biomass co-firing in 

coal plants, which will lead to expanded use of whole trees, will not be carbon neutral in any 

timeframe meaningful to addressing climate change. Regardless of these plants’ plans to use 

slash and logging residues, the available slash is insufficient to fuel the plants at the scale 

proposed, thus suggesting that these facilities will burn whole trees. (The data used in this 

analysis comes from the USDA Forest Service (Smith et al., 2007)).

Response: EPA disagrees with the commenters’ views that the deferral is not support by science 

or the law. EPA considers the commenters’ views about economic incentives for the biomass 

industry beyond the scope of this action. As explained in the preamble, EPA believes that based 

on information currently before the Agency, including information provided in response to the 

CFI and the proposal for this rule, that emissions from certain biomass feedstocks may have a 

neglible impact on atmospheric concentrations of CO2, or may be de minimis but also believes 

based on the complexity of this evidence that the deferral to allow for further study is warranted. 

EPA is using the time under this interim deferral to study the science surrounding biogenic CO2

emissions and is developing an accounting framework to assist permitting programs and sources. 

This interim deferral represents a permissible application of well-established administrative law 

doctrines, necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2

emissions, to develop a regulatory scheme that implements the CAA consistent with 

Congressional intent in a step-wise fashion designed to minimize administrative burdens and 

avoid unnecessary regulation of de minimis amounts of air pollution. Subsequent regulations to 

establish treatment of specific sources of biogenic emissions under the PSD and Title V 

programs, based on the results of the study and development of the accounting framework, are 

beyond the scope of this action.

Comment: Commenter 0048.1 stated biomass incinerators are getting federal stimulus dollars 

that could go to truly clean renewable energy sources like solar.
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Response: EPA considers the commenter’s views about economic incentives for the biomass 

industry beyond the scope of this action.

Comment: Commenter 0065.1 noted that biomass combustion emissions per unit of useful 

energy are usually higher than those from common fossil fuels. Even if source areas eventually 

re-sequester carbon, they need to accumulate more than the business as usual (BAU) levels in 

order to repay the carbon debt. This difference would be reflected in emissions reporting if all 

emissions were reported to EPA regardless of source. Emissions from biogenic sources might be 

permitted, however, to internally “offset” a portion of their emissions that do not result in a net 

increase of atmospheric biogenic CO2. Indirect emissions from processing and transport also 

contribute to the biogenic CO2 impacts of both biomass fuels and fossil fuels. Presumably, 

EPA‟s regulation under discussion would not apply to these indirect emissions and energy 

facilities would not be responsible for them, but these emissions sources should be regulated and 

limited by other means in order not to bias uses toward those with higher indirect emissions.

Response: EPA appreciates the views of the commenter. EPA notes that it has received other 

comments taking an opposing view of the science, which underscores the complexity of the 

science associated with accounting for biogenic CO2 emissions as part of the PSD and Title V 

permitting programs. Any subsequent regulations to establish treatment of specific sources of 

biogenic emissions under the PSD and Title V programs, based on the results of the study and 

development of the accounting framework, are beyond the scope of this action.

Comment: Commenter 0138.1 quoted statements by a forest owners’ organization that the 

deferral will spur greater use of biomass for fuel while continued uncertainty may cause the 

industry to “stagnate.” The commenter contended that the industry has been stagnant “for years”

and presented EIA data as the basis for his conclusion that the purpose or existing biogenic 

combustors is “as much about waste disposal as it is about energy generation.” The commenter 

sees no need to suddenly ramp up biogenic energy capacity prior to EPA doing due diligence on 

carbon impacts, because the commenter believes such action runs counter to EPA’s goal of 

reducing GHG emissions, and states that EPA’s concerns about discouraging use of biomass are 

inappropriate given the Agency’s failure to determine net carbon impacts. EPA’s 

acknowledgement that carbon accounting is complex, and that time is needed to study the 

question, does not justify leaving carbon emissions from the industry unregulated for three years. 

Far from representing a de minimis impact, the action will itself “spur” industrial development, 

and will increase the likelihood that large and essentially permanently unregulated facilities will 

be built in the three-year period.

Response: EPA disagrees with the commenter’s characterization of the state of the science 

supporting the deferral. As explained in the preamble, EPA believes that based on information 

currently before the Agency, including information provided in response to the CFI and the 

proposal for this rule, that emissions from certain biomass feedstocks may have a neglible impact 

on atmospheric concentrations of CO2, or may be de minimis but also believes based on the 

complexity of this evidence that the deferral to allow for further study is warranted. EPA is using 

the time under this interim deferral to study the science surrounding biogenic CO2 emissions and 

is developing an accounting framework to assist permitting programs and sources. This interim 

deferral represents a permissible application of well-established administrative law doctrines, 

necessitated by the scientific uncertainty surrounding the accounting of biogenic CO2 emissions, 
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to develop a regulatory scheme that implements the CAA consistent with Congressional intent in 

a step-wise fashion designed to minimize administrative burdens and avoid unnecessary 

regulation of de minimis amounts of air pollution. Subsequent regulations to establish treatment 

of specific sources of biogenic emissions under the PSD and Title V programs, based on the 

results of the study and development of the accounting framework, are beyond the scope of this 

action.

Comment: Commenters 0065.1, 0138.1 stated that EIA’s projected reductions in carbon 

emissions that would occur if a federal renewable electricity standard were passed reveals that 

the majority of the “reductions” are the result of replacing coal with biomass and simply not 

counting the emissions. There is good reason to assume that net emissions from the ramp-up in 

biomass energy that EIA envisions would be substantial. Considering biomass carbon neutral 

also incentivizes forest cutting and turns forests from carbon sinks into carbon sources.

Response: EPA considers the commenter’s views about economic incentives for the biomass 

industry and other renewable energy policies beyond the scope of this action. As explained in the 

preamble, EPA believes that based on information currently before the Agency, including 

information provided in response to the CFI and the proposal for this rule, that emissions from 

certain biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2, or 

may be de minimis but also believes based on the complexity of this evidence that the deferral to 

allow for further study is warranted. 

Comment: Commenter 0132.1 listed negative environmental impacts from using poultry litter, 

yard waste and municipal solid waste as fuel for power plants: 1) waste is diverted from existing 

recycling facilities with no benefit to the public or the environment; 2) poultry waste could 

otherwise be used as fertilizer; and 3) burning poultry waste releases nitrogen into the air. The 

commenter provided a comparison of emissions between power plants fueled with new wood, 

existing and new coal, existing biomass, and poultry litter, with the conclusion that for many 

pollutants, biomass fuel is dirtier than coal. Commenter 0141 provided similar arguments against 

the use of biomass fuels, and asked EPA to regulate all bioenergy emissions and stop 

construction of biomass facilities before more study is done.

Response: EPA notes that non-CO2 emissions from biogenic sources are not the subject of this 

deferral. EPA is using the time under this interim deferral to study the science surrounding 

biogenic CO2 emissions and is developing an accounting framework to assist permitting 

programs and sources. Subsequent regulations to establish treatment of specific sources of 

biogenic emissions under the PSD and Title V programs, based on the results of the study and 

development of the accounting framework, are beyond the scope of this action.

Comment: Commenter 0275 stated that subsidies for biomass burning should be denied 

because they make climate change worse in at least six significant ways. The commenter focused 

on wood burning electrical generating facilities:

1. Wood-burning biomass facilities emit more carbon dioxide per unit of electricity 

generated than any other energy source, converting on 15 to 25 percent of the energy in 

wood to electricity (versus 45 percent for coal and 60 percent for natural gas). The 

commenter compared three proposed biomass incinerators in Massachusetts to those of 
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the then highest CO2 emitting power plants in the Northeast. The biomass incinerators 

would emit 1.4 to 3.4 times the CO2 emissions of power plants. The commenter then 

compared these proposed incinerators to average values for other combustible fuel types, 

and found emissions would be significantly higher than coal, natural gas, and the national 

average.

2. Wood-burning biomass facilities damage and destroy forests and their capacity to remove 

CO2 from the atmosphere. The commenter cited a study that states “harvesting existing 

forests for electricity adds net carbon to the air”. 

3. Wood-burning biomass facilities require significant petroleum inputs (to cut, chip, and 

transport trees). Facility construction, incinerator start-ups, and transport of waste 

materials all require significant petroleum inputs. 

4. When other countries see the U.S. slashing and burning our own forests, they are less 

inclined to preserve their own forests. 

5. When biomass incinerators are subsidized, it is more difficult for green energy 

technologies to compete. Subsidies should be reserved for clean energy technologies, not 

incinerators. 

6. Typically, the wood not converted to electricity (75 to 85 percent of total energy in wood) 

is wasted as waste heat, which directly warms the atmosphere.

Response: EPA considers the commenter’s views about economic incentives for the biomass 

industry and other renewable energy policies beyond the scope of this action. As explained in the 

preamble, EPA believes that based on information currently before the Agency, including 

information provided in response to the CFI and the proposal for this rule, that emissions from 

certain biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2, or 

may be de minimis but also believes based on the complexity of this evidence that the deferral to 

allow for further study is warranted. Subsequent regulations to establish treatment of specific 

sources of biogenic emissions under the PSD and Title V programs, based on the results of the 

study and development of the accounting framework, are beyond the scope of this action.

Comment: Commenter 0049.1 stated it is not appropriate for EPA to create perverse incentives 

for indiscriminately burning biomass without safeguards in place to prevent use of unsustainable 

biomass sources such as forests. The commenter stated the biomass exemption will create 

incentives for regulated facilities to shift from burning coal to biomass, and expanding of 

biomass power means burning more whole trees. The commenter indicated that while fossil fuel 

carbon emissions [under CAA] are finally being properly accounted for, biomass emissions will 

be ignored for the next 3 years. The commenter noted that current laws and regulations already 

offer incentives for biomass use, i.e., American Recovery and Reinvestment Acts, 2008 Farm 

Bill, state portfolio standards, and Boiler MACT, and EPA’s deferral will further encourage 

wood biomass consumption.

Response: EPA considers the commenter’s views about economic incentives for the biomass 

industry and other renewable energy policies beyond the scope of this action. As explained in the 

preamble, EPA believes that based on information currently before the Agency, including 

information provided in response to the CFI and the proposal for this rule, that emissions from 

certain biomass feedstocks may have a neglible impact on atmospheric concentrations of CO2, or 

may be de minimis but also believes based on the complexity of this evidence that the deferral to 

allow for further study is warranted. Subsequent regulations to establish treatment of specific 
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sources of biogenic emissions under the PSD and Title V programs, based on the results of the 

study and development of the accounting framework, are beyond the scope of this action.
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123

12.0 Mechanism for Deferral and State Implementation

12.1 Implementing “Subject to Regulation” Definition

Comment: Commenter 0084.1 urged EPA to take a proactive stance in pressing the jurisdictions 

with EPA-approved programs to apply their PSD and Title V programs to GHG emissions. The 

commenter noted that this could be done by committing to “jawboning” the states or to expedite 

the approval process. Furthermore, the commenter suggested that EPA could issue, and 

encourage states to issue, so-called “no action assurances” on a blanket basis, as an exercise of 

prosecutorial discretion under Section 113 of the CAA, 42 U.S.C. § 7413, and state law. 

Commenter 0084.1 encouraged EPA to consider using its powers under Section 110(k)(6) of the 

Act, 42 U.S.C. § 7410(k)(6), to “correct” its mistakes in the SIP context unilaterally, without 

gaining the advance consent of the relevant jurisdiction. Without this action, the commenter 

contended that PSD/Title V applicability for biogenic CO2 emissions may be fulfilled only in 

some jurisdictions which would be an outcome at odds with a PSD program purpose to ensure a 

fairly “level playing field” from the standpoint of competition in the marketplace.

Commenter 0079.1 stated that EPA’s proposed deferral does not provide relief in SIP-approved 

states that either do not use the “Subject to Regulation” language in their PSD rules or that must 

conduct rulemaking to adopt EPA’s new interpretation of the term. Most states that required 

legislation/rulemaking have undertaken expedited or emergency laws or rulemakings in order to 

adopt EPA’s thresholds and definition of “subject to regulation.” EPA has approved some, but 

not all, of these SIP revisions. Presumably, these same states will require the same legislative or 

rulemaking actions to adopt EPA’s new deferral into their “subject to regulation” definition. 

There is no practical way that the deferral can be accomplished before July 1, 2011. Even then, if 

EPA issues a utility or refinery NSPS, additional rulemaking will be required by both EPA and 

the states to address the inclusion of any NSPS pollutant as a regulated NSR pollutant under 

EPA’s regulations.

To the extent EPA is going to defer regulation of biogenic CO2 emissions, it needs to do so in a 

manner that will last the full 3 years of the deferral, that can be adopted into SIPs quickly and 

efficiently, and that does not overly burden the states with serial rulemaking processes and SIP 

revisions.

Commenter 0094.1 believes EPA did not adequately address how states with SIP-approved PSD 

programs would implement the deferral. Most states with SIP-approved PSD programs have to 

go through their state rulemaking process in order to make changes to their PSD program, which 

can take about a year in many cases. In addition, EPA requires the state to submit, and get 

approved by EPA, a revision to the SIP to incorporate the change into the federally approved 

PSD program for that state. Under the CAA, EPA has up to 18 months to review such a 

submittal. EPA should address all these issues in the final rule preamble. EPA should specifically 

address what measures can be taken by the state or EPA to expedite the process for a SIPapproved state to be able to implement the deferral.

Four States (0033.1, 0038.1, 0069.1, and 0124.1) provided comments regarding implementation 

of the deferral amendments prior to July 1, 2011. Commenter 0038.1 noted Florida will not need 

to update its SIP for the deferral since Florida did not implement the federal mandate to add 
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124

GHG to its Title V and PSD programs; EPA is implementing Florida’s program through a 

Federal Implementation Plan (FIP), and when EPA updates 40 CFR 52.21(b)(49) as proposed, 

the FIP will automatically include the three-year deferral for biogenic CO2e without any action 

by Florida. Similarly South Carolina (0124.1) has taken legislative action that will ensure the 

deferral is incorporated into state permitting regulations upon promulgation. However, both 

Arkansas (0033.1) and Connecticut (0069.1) indicated that additional state rulemaking would be 

required following promulgation of the deferral, and these amendments cannot be completed 

prior to July 1, 2011. Commenter 0069.1 added that the limited number of expected biogenic 

applications did not warrant rule amendments and that any new applications for biogenic sources 

would be processed consistent with current state regulations without any expectation of 

“administrative hardship” based on EPA’s BACT guidance for biogenic sources.

Commenter 0086.1 stated that EPA must provide relief to SIP-approved states that either do not 

use the “subject to regulation” language in their PSD rules or that must conduct rulemaking to 

adopt the proposed deferral revisions, and went on to say that there is no practical way that the 

deferral can be codified in all state permitting rules before July 1, 2011. 

Commenter 0064.1 stated that it is imperative that EPA finalize the deferral as soon as possible, 

so that states such as Washington State which have already incorporated the Tailoring Rule by 

reference have sufficient time to enact their own deferral. The Washington State Department of 

Ecology has already adopted the Tailoring Rule by reference, effective April 1, 2011. Thus, upon 

enactment of a deferral by EPA, Ecology will have to engage in a new round of rulemaking to 

respond accordingly. Therefore, EPA should enact a deferral immediately upon conclusion of the 

comment period after an appropriate time to consider and respond to comments, so that Ecology 

can enact its deferral prior to July 1, 2011.

Response: Many commenters seem to believe that the deferral for biogenic CO2 must be 

adopted into their permitting programs and approved by EPA as of the beginning of step 2 of the 

Final Tailoring Rule (July 1, 2011). Neither the proposed deferral rule nor the final deferral rule 

requires States to adopt the three-year deferral or to adopt it by any specific deadline, thus the 

deferral is entirely voluntary for state, local, and tribal Title V and PSD programs. Because the 

deferral is voluntary, EPA does not need to conduct any SIP correction procedures under the 

authority of Section 110(k)(6) of the Act to revise state programs, or for states to revise their 

PSD SIPs by July 1, 2001, as commenters suggested. The preamble for the proposal discusses

the beginning of step 2 of the Tailoring Rule as a time when more sources would be subject to 

permitting, including because sources could be subject to Title V without a prerequisite that they 

also be subject to PSD and because they could be subject to PSD for GHG without being subject 

first for another regulated NSR pollutant, but not in the context of a requirement for deferral 

implementation by States. EPA notes that the deferral will be mandatory when it takes effect for 

purposes of the PSD program under part 52 and the Title V program under part 71, where EPA is 

the permitting authority. 

As for encouraging states to adopt the deferral, the proposal discusses that states should defer 

biogenic CO2 emissions for the same reasons that EPA thought they should be deferred (e.g., the 

need for more time to figure out how to address technical, scientific, and practical issues related 

to biogenic CO2 without disrupting the proper functioning and timeliness of the permitting 

programs). Also, the preamble strongly encourages states that wish to adopt the three-year
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125

deferral to submit SIP revisions or Title V program revisions, but it does not mandate such 

submittals, recognizing that some States may not have any sources that combust biomass, or may 

have only a few, and may have adequate information and resources as to the nature of biogenic 

emissions from those sources. 

Also concerning states where the deferral will not be effective, EPA provided some guidance in 

the preamble concerning PSD for Biogenic CO2 Sources. In that guidance, EPA stated that 

biogenic CO2 emissions might need to be addressed in PSD permitting until such time as the 

deferral took effect. Thus, PSD permit programs might require PSD permits issued prior to the 

deferral becoming effective to meet BACT requirement for GHG, including biogenic CO2

emissions. 

We appreciate the suggestion on how to expedite state approvals for programs changes. 

With reference to one commenter’s request for prosecutorial discretion, EPA retains such 

discretion to be applied for purposes of enforcement action against specific owners and operators 

but such discretion would not apply to state agencies because the deferral for biogenic CO2 that 

is the subject of this rulemaking is voluntary for states. 

12.2 Public Health and the Environment

Comment: Commenter 0048.1 stated that due to state budget cuts targeting regulatory and 

enforcement agencies, states will not be able to protect public health and the environment 

without critical federal leadership and support.

Response: We appreciate the concern of the commenter but we have no evidence that the 

approach we are taking in this deferral will have any negative effects on public health and the 

environment. We explained in the preamble to the final rule that the deferral is designed to 

reduce burdens on states and sources alike for purposes of PSD and Title V applicability while 

we conduct a detailed examination of the science and technical issues associated with biogenic 

CO2 emissions. We also explained that the extensive workload requirements that PSD and 

Title V permit applications for bioenergy facilities and other sources of biogenic CO2 emissions 

would strain permitting authority resources. This would result in delays in processing permits 

for other applicants. We also explained that devoting limited resources to biomass would not be 

productive in light of the previously described possibility that EPA may ultimately determine 

that the utilization of some biomass feedstocks for bioenergy has a negligible or de minimis 

impact on atmospheric concentrations of CO2. Subjecting biogenic CO2 emissions to permitting 

may be counterproductive because it could discourage utilization of the biomass feedstock as 

fuel which, in some cases, would clearly reduce net atmospheric CO2 levels. Requiring 

permitting before conducting the detailed scientific examination we discussed in the proposal 

might actually discourage projects that would have a net benefit for the atmosphere. For 

example, requiring permitting for facilities seeking to generate energy from the combustion of 

dead trees, including those killed due to a widespread event like the mountain pine beetle 

epidemic, is likely to discourage the utilization of a readily available resource that would clearly 

reduce CO2 emissions (e.g., by removing and utilizing biomass material that would otherwise be 

susceptible to fire or decompose in the forest, leading to CO2 and CH4 emissions from 

decomposition). Likewise, combustion of CH4-laden biogas (e.g., from landfills or other large 
12.0 Mechanism for Deferral and State Implementation

126

sources of methane) for energy production reduces overall CO2e emissions because of the higher 

GWP for CH4.

12.3 Consistency of Deferral Regulations Amongst the States

Comment: Commenter 0049.1 noted that states have inadequate regulations for biomass. The 

commenter indicated that only Massachusetts is capable of adopting sound regulations for 

biomass, citing their imminent requirement that projects provide significant near-term net 

reductions in GHG emissions, and noted that Tennessee and most of the South are not capable of 

putting in place adequate carbon pollution safeguards for the next 3 years.

Commenter 0087.1 objected to the possibility that variations in SIPs could lead to a non-uniform 

deferral that could treat biogenic CO2 emissions differently from state to state. The commenter 

believes EPA should promulgate regulations that require states to follow the three-year deferral 

for biogenic CO2 and should disapprove any state programs that do not. Commenter 0074.1 

stated that EPA should limit approval of SIPs that are inconsistent with the proposed deferral 

rule using the same mechanism used for the Tailoring Rule.

Commenter 0078.1 urged EPA to adopt and implement a uniform approach to this deferral that 

will ensure consistency and predictability from state-to-state. The commenter stated EPA should 

strongly encourage states to adopt the provision.

Response: The proposal did not specifically require each State to revise its PSD and Title V 

permitting programs (required under parts 51.166 and 70) to impose the deferral for 3 years, 

although it was clear that the proposal was intended to revise the permitting programs that EPA 

implements (required under parts 52.21 and part 71) for this purpose and it was clear that EPA 

intended to implement the deferral by changing its implementing regulations. Many State 

commenters on the proposal seemed to assume that the deferral was mandatory for the States and 

questioned how they would revise their SIPS and Title V programs by July 1 2011, as they read 

EPA’s proposal to require.

For the purposes of this final rule, EPA is clarifying that each State may decide if it wishes to 

adopt the deferral and proceed accordingly, with appropriate program changes, if needed. Also, 

EPA suggests that each state communicate with its stationary sources its intent in this regard. 

Because the deferral is voluntary, States that do not wish to revise their current permit programs 

do not need to make any program changes in response to this final rule. Also, States that do wish 

to adopt the deferral do not need to make any necessary changes by July 1, 2011, the start of step 

2 under the Tailoring Rule. 

However, although state programs changes are not mandatory under today’s final rule, EPA sees 

several reasons why a state should adopt the deferral in its State programs, and many of these 

reasons are the same reasons why EPA is adopting the deferral for the permit programs we 

implement (e.g., the need for more time to figure out how to address technical, scientific, and 

practical issues related to biogenic CO2 without disrupting the proper functioning and timeliness 

of the permitting programs). Also, the proposal strongly encouraged states that wish to adopt the 

three-year deferral to submit SIP revisions or Title V program revisions, but it did not mandate 

such submittals, recognizing that some States may not have any, or may have only a few, sources 
12.0 Mechanism for Deferral and State Implementation

127

that combust biomass, and may have adequate information and resources as to the nature of 

biogenic emissions from those sources, and this is the approach of this final rule.

EPA also issued interim guidance entitled, “Guidance for Determining Best Available Control 

Technology for Reducing Carbon Dioxide Emissions from Bioenergy Production” to help 

permitting authorities establish a basis for concluding that under PSD Program the combustion of 

biomass fuels can be considered BACT for biogenic CO2 emissions at stationary sources until 

such time as the deferral becomes effective. EPA wishes to clarify that the guidance is nonbinding and BACT determinations made in accordance with the guidance may nonetheless be 

subject to challenge in each permitting action. Accordingly, the interim guidance does not 

provide the same level of certainty to sources and decrease in administrative burdens to 

permitting authorities and sources that the deferral does. 

12.4 Effect of Regulating GHG through NSPS

Comment: Commenter 0086.1 recognized that EPA’s use of the definition of “subject to 

regulation” as the foundation for the proposed deferral language makes the duration of the 

deferral period contingent upon EPA’s treatment of biogenic CO2 in NSPS proceedings 

conducted during deferral, because upon promulgation of any Section 111 standard for CO2, the 

PSD applicability language at 51.166(a)(7)(iv)(a) and the definition of “regulated NSR pollutant”

at 51.166(b)(49)(ii) can make CO2 subject to PSD via applicability criteria that are independent 

of the definition of “subject to regulation” unless biogenic CO2 emissions are exempted or 

congruently deferred from applicability under the GHG NSPS; the commenter specifically 

referenced EPA’s intent to promulgate Section 111 standards for GHG for the utility and refining 

sectors by May 26, 2012. Commenter 0086.1 recommends adding the following language at the 

end of the proposed deferral amendments to provide certainty regarding the effect of a future 

GHG NSPS on the PSD deferral:

Notwithstanding section 52.21(b)(50)(ii) [or section 51.166(b)(49)(ii) for the SIP guideline], 

the emissions identified in the preceding sentence shall not be included in any determination 

of applicability under this section prior to [DATE 3 YEARS AFTER THE EFFECTIVE 

DATE OF THE FINAL DEFERRAL RULE]. 

Response: EPA appreciates the views of the commenter but notes that regulation of CO2, 

including from biogenic sources, under the CAA Section 111 NSPS program is beyond the scope 

of this action. EPA will keep the commenter’s views in mind in the development of any such 

regulations in the future.

12.5 Effect of the Deferral when Co-fired Feedstocks or Mixed Fuels

Comment: Commenter 0079.1 stated that EPA needs to also clarify how facilities that co-fire 

biogenic feedstocks and fossil fuels will conduct PSD applicability analyses in states that have 

adopted the 2002 NSR rules and states that have not. As an example, if a source is installing a 

new emissions unit that will have biogenic fuels as a primary feedstock, and fossil fuels as a 

backup, the source should not be required to calculate future potential emissions based on fossil 

fuel firing 100% of the time. EPA needs to clarify these points since many facilities will use 

fossil fuels as backup or alternate fuels. Moreover, in states that apply an actual-to-potential 
12.0 Mechanism for Deferral and State Implementation

128

emissions test, potential emissions should not be calculated based on use of 100% of a back-up 

fossil fuel but rather an allocation should be made and emissions attributable to biogenic 

feedstocks should not be included.

If EPA requires emissions to be based on a fossil fuel that is a backup, the deferral proposed here 

will have little effect on PSD and Title V applicability determinations because the fossil fuelbased emissions will likely result in PSD or Title V being triggered for GHG.

Response: In the preamble for the proposal EPA stated that the portion of the CO2 emissions 

from a facility that result from biologically-derived material is deferred and not included for 

purposes of determining PSD applicability during the deferral period. If fossil-derived fuel is 

used within a facility to provide energy for a process that also uses biological material, the 

emissions associated with the fossil fuel must be counted toward PSD applicability regardless of 

the use of the biological material. Specifically, the emissions that are deferred from applicability 

include, but are not limited to:

• CO2 generated from the biological decomposition of waste in landfills, wastewater 

treatment or manure management processes;

• CO2 from the combustion of biogas collected from biological decomposition of waste in 

landfills, wastewater treatment or manure management processes;

• CO2 from fermentation during ethanol production;

• CO2 from combustion of the biological fraction of municipal solid waste or biosolids;

• CO2 from combustion of the biological fraction of TDF; and

• CO2 derived from combustion of biological material, including all types of wood and 

wood waste, forest residue, and agricultural material.

In the final rule, we have not significantly added to the guidance provided in the proposal on this 

subject and this request for further detailed additional guidance on the implementation of PSD 

under various circumstances is outside of the scope of this rulemaking. In the interim, this

question is best addressed by the specific permitting authority based on source-specific 

considerations after reviewing the state regulation in effect in the state where the analysis occurs

12.6 State Numbers of Sources, Resource Constraints, and Preferences

Comment: Regarding EPA’s request in the proposal for States to advise of numbers and types 

of existing biomass facilities, expectations for new facilities during the deferral, and resource 

constraints, fifteen States provided comments as summarized in the following table:

State Number/Type of Existing Sources

Estimated Major 

Biomass Projects 

During Deferral

Resource 

Constraints

Alaska

(0114.1)

No comment No comment No comment
12.0 Mechanism for Deferral and State Implementation

129

State Number/Type of Existing Sources

Estimated Major 

Biomass Projects 

During Deferral

Resource 

Constraints

Arkansas

(0033.1)

27 facilities, all with Title V permits:

1. Landfills – 13

2. Facilities with wood fired boilers 

- 6

3. Paper mills – 6

4. Grain processing facilities (rice 

hull burning) – 2

One or two PSD permits 

per year for biomass 

sources expected. Big 

increase in permits not 

expected. Landfill 

expansions could trigger 

PSD. 

ADEQ cannot 

estimate resource 

impacts and 

constraints. 

Connecticut

(0069.1)

2 permits have been issued under NSR

PSD permit program, but neither have 

begun construction. The state also has 

several smaller wood-fired boilers, 

several landfills that flare landfill gas, 

and one TDF facility. 

A limited number is 

expected.

The state is not 

concerned with 

resource 

constraints.

Florida

(0038.1)

9 biomass facilities:

1. FB Energy (wood waste/energy 

crops)

2. ADAGE (wood)

3. Highlands ethanol (energy crops)

4. St. Lucie County (MSW)

5. University of Florida (cellulosic 

biomass)

6. American Renewables (wood)

7. INEOS Bioenergy (waste)

8. Southeast Renewable Fuels 

(sorghum)

9. Palm Beach Renewable Energy 

Facility (MSW)

Currently processing 

applications for 2 

bioenergy projects, and 

7 additional projects are 

in planning and 

development. Number 

of future applications 

difficult to estimate.

No comment

Georgia

(0094.1)

Eight sources are permitted which may 

be subject to Step 2 of the Tailoring 

Rule.

Five pending 

applications

No comment

Kentucky 

(0047.1)

No comment No comment No comment

Louisiana

(0100.1)

No comment No comment No comment
12.0 Mechanism for Deferral and State Implementation

130

State Number/Type of Existing Sources

Estimated Major 

Biomass Projects 

During Deferral

Resource 

Constraints

Massachusetts 

(0101.1; 

0105.1)

30 facilities reported biogenic 

emissions In 2009, 24 with Title V 

permits: 

1. 16 landfill with gas combustion 

(flare or power generation)

2. 6 municipal waste incineration

3. 5 industrial, commercial or 

institutional facility with biofuel boiler or engine

4. 1 biomass-fueled electric utility 

steam generator

5. 1 wastewater treatment plant 

burning sludge digester gas

6. 1 food processor with woodfired smoker oven

2 proposed biomassfueled electric utility 

steam generator 

facilities currently under 

review, each with 

potential biogenic CO2

emissions greater than 

100,000 tons per year.

Massachusetts has 

adequate 

information and 

resources as to the 

nature of biogenic 

emissions from 

Massachusetts 

facilities for the 

purposes of our air 

pollution control 

program. 

Massachusetts is 

not inclined to 

defer inclusion of 

biogenic CO2

emissions.

Minnesota

(0102.1)

42 biomass facilities of the following 

types:

1. Wood products/paper – 20

2. Power plants – 8

3. Universities/schools/hospitals – 6

4. Ethanol and mining – 8

1-2 No comment

Oklahoma

(0037.1)

Four major sources that utilize wood as 

fuel. Sources that burn biogas were not 

included.

No significant changes. Short-term 

impacts reduced 

by deferral but 

concerned about 

resources needed 

to implement 

GHG and other 

core program 

areas (i.e. NAAQS 

and area toxics).

Oregon

(0058.1)

16 major sources of biogenic CO2

including pulp and paper, wood 

products, EGUs, and landfills.

Expect 3-5 new 

biogenic EGU projects.

2 additional staff 

are needed to 

implement GHG 

program.
12.0 Mechanism for Deferral and State Implementation

131

State Number/Type of Existing Sources

Estimated Major 

Biomass Projects 

During Deferral

Resource 

Constraints

Pennsylvania

(0135.1)

Stationary sources that combust 

biomass materials:

1. MSW combustors – 6

2. MSW landfills – 34

3. Wood burners – 9

4. Sewage sludge incinerators – 9

Unable to estimate No comment

South 

Carolina

(0124.1)

1. Approximately 5 biomass power 

generation sources

2. Seven pulp/paper sources (black 

liquor, wood chips)

3. Approximately 50 boilers/

furnaces/kilns

Four biomass power 

generation applications 

being processed at this 

time. Number of future 

applications difficult to 

estimate.

Plan to use scarce 

resources on other 

revised EPA rules.

Vermont

(0355)

No comment No comment No comment

Wisconsin

(109.1)

Sources that will be impacted:

1. 100 companies with over 250 

combustion units (wood/wood 

waste)

2. 100 wastewater treatment plants 

burning bio-gas.

3. 60 large landfills with some 

energy recovery.

4. 20 ethanol plants

No comment Significant 

workload 

implications for 

WDNR’s air 

permitting staff 

would have been 

expected without a 

deferral. 

Commenter 0102.1 noted that 31 of the 42 facilities in Minnesota that are permitted to combust 

biomass already hold Title V permits and 23 of those are also major for NSR. Only 11 facilities 

have state-only permits. With EPA’s proposed three-year deferral of permitting requirements for 

biogenic sources, the commenter could defer requiring an application for those 11 facilities 

should they otherwise need to revise permit limits or obtain a federal operating permit. The 

commenter also stated that while another one or two applications may be expected during the 

deferral, no new applications have been submitted at this time. The commenter also stated that 

nine Minnesota permitted ethanol facilities – that would not otherwise trip the 100,000 ton 

threshold from purely fossil fuel CO2 emissions (plus CH4 and N2O for EGUs) – would trip the 

July 1 threshold (as new facilities) if biomass CO2 totals were to be included in GHG totals for 

PSD applicability determinations. Of the nine, two are newer facilities (or units) added since 

2000. These data are from the Minnesota GHG emission inventory, for years 2006- 2008. 
12.0 Mechanism for Deferral and State Implementation

132

Commenter 0069.1 offered information concerning the number and types of biogenic CO2

emissions sources in Connecticut, and the intentions of Connecticut Department of 

Environmental Protection (CTDEP) with regard to permitting such sources. The CTDEP has 

issued two permits under the commenter’s NSR PSD permit program. Both permits were issued 

prior to January 2, 201 l, to Plainfield Renewable Energy and Montville Power. Neither 

Plainfield Renewable Energy nor Montville Power has begun construction. In addition to the 

utility biomass sources, Connecticut has several smaller wood-fired boilers, several landfills that 

flare landfill gas and one tire-fired incinerator.

Response: EPA thanks the State commenters for the detailed information relevant to 

implementation of the deferral of biogenic CO2 in the states. In the context of encouraging states 

to revise SIPs and/or Title V programs to adopt the three-year deferral, EPA requested that each 

State advise EPA as to the number and type of biomass sources in the State and what the State 

expects to be the number and type of biomass sources over the next three years. EPA also asked 

about the State’s resource constraints. EPA notes that this information seems to support EPA’s 

assumption of the proposal that the deferral not be mandatory because of the limited number of 

sources that combust biomass in various states and the lack of information and resources, in 

some cases, as to the nature of biogenic emissions from those sources.
13.0 Calculation Methods During Deferral

133

13.0 Calculation Methods During Deferral

13.1 Methods for Determining Biogenic CO2 Emissions (general)

Comment: Commenter 0087.1 suggested that every project is different and contain a varying 

amount of uncertainty therefore the EPA should not select a unified approach or method but 

rather evaluate each permit application individually. The commenter also suggests that while the 

GHG Mandatory Rule can be used as a reference, the accounting approach should not be 

required for all facilities. 

Response: The final rule does not contain any specific methods or requirements to use specific 

methods for calculating biogenic CO2 emissions. EPA agrees the methodologies in the GHG 

Reporting Program for biogenic CO2 emissions can serve as a reference. 

Comment: Commenter 0052.1 suggested that the deferral and final resolution should specify 

that biogenic CO2 emissions at the point of combustion are zero, consistent with the EU and a 

recent EPA lifecycle greenhouse gas assessment approach. 

Response: EPA is considering the issues the commenter raised in its detailed examination of the 

science and technical issues associated with accounting for biogenic CO2 emissions. They are 

outside the scope of this rulemaking. 

Comment: Conversely, another commenter (0104.1) suggested that EPA has long maintained 

that for PSD purposes applicability must be determined based solely upon a source’s direct 

emissions and that all direct emissions from operation of a source “under its physical and 

operational design” must be counted in determining applicability.

Response: EPA is granting the deferral of biogenic CO2 emissions from stationary source 

permitting requirements because the issue of accounting for the net atmospheric impact of 

biogenic CO2 emissions is complex enough that further consideration of this important issue is 

warranted. During the three year deferral period, EPA will conduct a detailed examination of the 

science associated with biogenic CO2 emissions from stationary sources, including engaging 

with federal partners, technical experts, and an independent scientific panel to consider technical 

issues. Based on the feedback from the scientific and technical review, EPA will then undertake 

a rulemaking to determine how biogenic CO2 emissions should be treated and accounted for in 

PSD and Title V permitting programs. The deferral focuses on biogenic CO2 emissions from 

stationary sources subject to the PSD and Title V programs.

Comment: Commenter 0114.1 requests that EPA either amend 40 CFR 98 to address fish oil or 

allow methods other than those in 40 CFR 98 for calculating the CO2 emissions from biomass 

should no emission factors or heating values be provided by EPA for a given biomass fuel (such

as fish oil).

Response: The final rule does not contain any specific methods or requirements to use specific 

methods for calculating biogenic CO2 emissions. EPA agrees the methodologies in the GHG 

Reporting Program for biogenic CO2 emissions can serve as a reference. 
13.0 Calculation Methods During Deferral

134

Comment: One commenter (0124.1) requests that EPA issue guidance with examples on how to 

determine a source’s biological fraction and the CO2 emissions from that fraction. The 

commenter also requested that EPA address how the deferral impacts projects utilizing the 

actual-to-projected-actual applicability test. In determining a project's significant emission 

increases, facilities have the option to use the actual-to-potential or the actual-to-projected-actual 

applicability tests. Under §52.21(r)(d)(iii), facilities using the actual-to-projected-actual applicability 

test must calculate and record actual annual emissions for a period of 5 years or, if there was an 

increase in capacity or potential to emit, for 10 years. Three years from the deferral, CO2 emissions 

from the biogenic source may or may not be exempt, depending on the outcome of the deferral. The 

EPA should clarify that biogenic CO2 emissions will not have to be included in the emissions 

calculations under §52.21(r)(d)(iii) for the remaining time frame if the project occurred during the 

deferral period.

Response: The purpose of the three-year deferral is to better understand the impacts of biogenic 

CO2 emissions. Stationary sources that combust biomass and construct or modify during the 

three-year deferral period will avoid the application of PSD to the biogenic CO2 emissions 

resulting from those actions. Note that the deferral applies only to CO2 emissions and does not 

affect non-GHG pollutants or other greenhouse gases.

No decision has yet been made regarding permit applications and permits issued after the threeyear deferral period expires. During the three year deferral period, EPA will conduct a detailed 

examination of the science associated with biogenic CO2 emissions from stationary sources, 

including engaging with federal partners, technical experts, and an independent scientific panel 

to consider technical issues. Based on the feedback from the scientific and technical review, EPA 

will then undertake a rulemaking to determine how biogenic CO2 emissions should be treated 

and accounted for in PSD and Title V permitting, including concerns such as those raised by the 

commenter above. 

To date, EPA issued interim guidance entitled, “Guidance for Determining Best Available 

Control Technology for Reducing Carbon Dioxide Emissions from Bioenergy Production” and 

various methods are available to calculate both the biogenic and fossil portions of CO2

emissions, including those methods contained in the GHG Reporting Program (40 CFR part 98).

EPA will decide at the time of the rulemaking for treatment and accounting of biogenic CO2

emissions whether further guidance, examples, and other supporting materials will be needed.

13.2 Methods for Determining Biogenic CO2 Emissions (mixed fuels)

Comment: Three comments were received which specifically addressed determining biogenic 

CO2 Emissions for mixed fuels. Two commenters (0052.1 and 0095.1) both endorsed flexible 

approaches in which the facilities should document and use the best available information to 

calculate biogenic emissions. The third commenter (0077.1) recommended that facilities use 

standard gas metering devices or standard engineering calculations for gas combustion to 

account for mixed fuels. Commenter 0106.1 suggested that wood fuel sources meet FSC

certification standards. Furthermore commenter 0022 recommended that stationary sources 

combusting mixed fuels use ASTM D6866 testing to accurately measure their biogenic CO2

emissions. This standard method is used to determine the exact percentage of biogenic CO2

emissions produced from combusting fuels that are partly fossil and partly biomass, e.g. 
13.0 Calculation Methods During Deferral

135

municipal solid waste, used tires, and sewage sludge. ASTM D6866 has already been 

incorporated in the EPA's Mandatory Greenhouse Gas Reporting Rule (40 CFR Part 98) and 

Western Climate Initiative's Mandatory Reporting Requirements, among others.

Response: The final rule does not contain any specific methods or requirements to use specific 

methods for calculating biogenic CO2 emissions. For stationary sources co-firing fossil fuel and 

biologically-based fuel, and/or combusting mixed fuels (e.g., TDF, MSW, etc.), the biogenic 

CO2 emissions from that combustion are included in this deferral. However, as stated above, the 

fossil CO2 emissions are not. Various methods are available to calculate both the biogenic and 

fossil portions of CO2 emissions, including those methods contained in the GHG Reporting 

Program (40 CFR part 98). Further, EPA issued interim guidance entitled, “Guidance for 

Determining Best Available Control Technology for Reducing Carbon Dioxide Emissions from 

Bioenergy Production” and various other methods are available to calculate both the biogenic 

and fossil portions of CO2 emissions, including those methods contained in the GHG Reporting 

Program (40 CFR part 98). EPA will decide at the time of the rulemaking for treatment and 

accounting of biogenic CO2 emissions whether further guidance, examples, and other supporting 

materials will be needed, but for most permitting purposes, the source should work with the 

permitting authority to determine the best methods for calculating these emissions considering 

site-specific factors. 

Comment: Commenter 0022 pointed out an oversight in the EPA GHG Reporting Rule 

concerning the biogenic CO2 emissions of stationary sources that combust sewage sludge as fuel. 

Based on the commenter’s internal lab tests using ASTM D6866, sewage sludge/biosolids are 

only about 80 percent biogenic. The commenter cited the work of researchers that have 

demonstrated that sewage sludge contains a significant amount of fossil carbon due to detergents, 

shampoos, and other petroleum-based consumer products that enter the waste stream. The 

commenter encouraged EPA to take into account the fossil inputs in materials assumed to be 100 

percent biomass or renewable, such as sewage sludge and demolition wood with petroleumbased paint or adhesives.

Response: We acknowledge the commenter’s suggestion for the GHG Mandatory Reporting 

Rule. We note that this comment is outside the scope of the deferral rule under consideration, 

but we may further consider this comment as we develop accounting methodologies for biogenic 

CO2.
14.0 Interim Guidance to Address Biogenic CO2 Sources Under PSD Review

136

14.0 Interim Guidance for Biogenic CO2 Sources Under PSD 

Review

EPA issued interim guidance entitled, “Guidance for Determining Best Available Control 

Technology for Reducing Carbon Dioxide Emissions from Bioenergy Production,” in March 

2011 concurrent with the proposal for this action. EPA received a number of comments on the 

contents of the guidance, which EPA considers to be beyond the scope of this deferral action. 

We are not intending to revise the interim guidance at this time. EPA is granting the deferral of 

biogenic CO2 emissions from stationary source permitting requirements because the issue of 

accounting for the net atmospheric impact of biogenic CO2 emissions is complex enough that 

further consideration of this important issue is required. Nevertheless we are summarizing a 

number of the significant comments raised about the guidance and providing clarity on the nature 

of the guidance, where appropriate. 

14.1 Interim Guidance to Address Biogenic CO2 Sources Under PSD 

Review

Comment: Commenter 0101.1 noted that if EPA chooses to follow precedent and regulate 

biofuels like other fuels, then at a minimum, emissions will be reduced because projects will be 

required to utilize efficient combustion technologies, as is the case for fossil fuel-fired projects. 

If EPA chooses to treat biogenic emissions differently, then EPA should move forward 

immediately to develop appropriate guidance which accounts for impacts of biomass 

combustion.

Commenter 0070.1 suggested if EPA cannot permanently exclude biomass combustion 

emissions, a rational alternative to a complete exemption could be to issue a (non-interim) BACT 

guidance document laying out credible scientifically sound accounting methodologies that take 

into account the carbon debt associated with burning biomass for energy which concludes that 

the combustion of biomass fuel is considered BACT.

Response: EPA issued its “Guidance for Determining Best Available Control Technology for 

Reducing Carbon Dioxide Emissions from Bioenergy Production” on March 21, 2011. This 

Guidance elaborates on the November 2010 GHG Permitting Guidance, and encourages states to 

consider energy efficiency as part of their permitting process for bioenergy projects. The interim 

guidance was intended to help permitting authorities establish a basis for concluding that under 

the PSD Program the combustion of biomass fuels can be considered BACT for biogenic CO2

emissions at stationary sources until such time as the deferral becomes effective. The unique 

lifecycle characteristics of biogenic feedstocks, and the extent to which characterizing the full 

carbon cycle of the fuel source is appropriate when considering the net atmospheric impact of 

emissions from a stationary source, are the subject of EPA’s ongoing detailed examination of the 

science and technical issues associated with biogenic CO2 emissions. Once that work is 

complete the Agency intends to undertake a rulemaking to establish the treatment of these 

emissions in the PSD and Title V programs. Thus, EPA is unable to provide more specific 

guidance of the type requested by these commenters until it completes these actions.
14.0 Interim Guidance to Address Biogenic CO2 Sources Under PSD Review

137

Comment: Commenter 0350.1 stated that EPA’s approach in the Bioenergy BACT Guidance is 

arbitrary, unsupportable, and all but certain to encourage legally and factually deficient BACT 

determinations. The commenter stated that biomass feedstocks and the resulting CO2 emissions 

must be analyzed in the context of facility-specific, case-by-case BACT determinations, and to 

the extent that biological feedstocks have unique lifecycle characteristics such that biogenic CO2

emissions warrant different treatment under CAA from other pollutants, these characteristics 

cannot form the basis of a broad exemption from PSD and Title V permitting. The commenter 

stated the Bioenergy BACT Guidance fails to provide necessary technical support for case-bycase Bioenergy BACT determinations. The commenter noted the BACT Guidance is a departure 

from past EPA practice and explicitly encourages permitting authorities to substitute broad 

policy judgments for the case-by-case analysis required by statute and regulations.

Commenter 0106.1 opposed EPA’s March 2011 interim guidance for BACT for reducing CO2

from bio-energy production, because the interim guidance inappropriately supports all biomass 

burning for energy as BACT for CO2, and this interim policy provides no consideration of the 

source of the fuel used or whether that proposed facility would be a net source or sink for CO2. 

The commenter believes it is scientifically more appropriate, to consider the full carbon cycle of 

the fuel source during BACT analyses, as is discussed but not applied in the interim guidance for 

BACT.

Response: EPA is not revising the guidance at this time. However, commenters may raise these 

concerns about the guidance in the context of individual permitting actions where the guidance is 

applied. The guidance is non-binding and BACT determinations made on a case-by-case basis 

may reflect consideration of additional information. As stated in the March 2011 interim 

guidance document, EPA has not provided a final determination of BACT for any particular 

source, since such determinations can only be made by individual permitting authorities on a 

case-by-case basis after consideration of the record in each case. Upon consideration of the 

record in an individual case, if a permitting authority has a reasoned basis to address particular 

issues in a different manner than EPA recommends in guidance, they have the discretion to do 

so. In addition, BACT determinations based on the reasoning in the guidance may be subject to 

challenge in each permitting action. The unique lifecycle characteristics of biogenic feedstocks, 

and the extent to which characterizing the full carbon cycle of the fuel source is appropriate 

when considering the net atmospheric impact of emissions from a stationary source, are the 

subject of EPA’s ongoing detailed examination of the science and technical issues associated 

with biogenic CO2 emissions. Once that work is complete the Agency intends to undertake a 

rulemaking to establish the treatment of these emissions in the PSD and Title V programs. Thus, 

EPA is unable to provide more specific guidance on considering the full carbon cycle in the 

context of BACT reviews until it completes these actions.

Comment: Commenter 0350.1 stated that EPA has not shown that biomass is a “clean fuel.” 

The commenter stated if EPA determines it has authority to determine that biomass constitutes a 

clean fuel based on a full lifecycle analysis, then the analysis must be conducted in accordance 

with the CAA requirements, i.e., using top-down, 5-step process from the 1990 NSR Workshop 

Manual and a case-by-case analysis. The commenter noted that while EPA may prefer to 

determine that certain types of biomass probably constitute BACT, it must conduct an analysis at 

the facility to demonstrate that this is the case. The commenter noted that historically, whether a 
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given fuel type constitutes a “clean fuel” has focused on a facility’s at-the-stack emissions, that 

is, whether the fuel is “inherently cleaner” in terms of at-the-stack emissions than an alternative. 

In these terms, biomass could never qualify as BACT because, per unit of energy, biomass 

combustion emits more CO2 than coal and significantly more than natural gas. Therefore, any 

determination that biomass is “cleaner” than fossil fuels must necessarily be based on an 

accounting of the CO2 emissions associated with the full lifecycle of the feedstock.

The commenter stated the CAA requires each BACT determination be made on a case-by-case 

basis, where the permitting authority may take into account energy, environmental, and 

economic impacts and other costs. The commenter noted they are aware of no authority that 

allows a permitting authority to deviate from this requirement. The commenter indicated that 

EPA has not offered facts or evidence demonstrating a case-by-case analysis would be complex 

and time-consuming in every instance and has not adequately explained why the complexity 

justifies a de facto exemption from the case-by-case BACT requirement, and this contravenes the 

plain language of the statute.

The commenter stated that EPA’s application of the top-down BACT analysis in the Bioenergy 

BACT Guidance is misguided. The commenter noted that EPA’s own guidance which has been 

in effect and applied by permitting authorities for decades demonstrates that the available BACT 

options, including clean fuels, must be determined at Step 1, and then may be discounted at 

further steps in the analysis. The commenter stated that if permitting authorities are to conclude 

that biomass constitutes an available control technology based on lifecycle analysis, this must 

occur at Step 1 and not at Step 4. The commenter objected to EPA’s conclusion that a lifecycle 

analysis may be conducted at Step 4, as this is contrary to decades-long precedent that requires 

that a fuel be listed as a control technology at Step 1 because of its effectiveness in reducing 

emissions.

Response: The interim guidance was intended to help permitting authorities establish a basis for 

concluding that under PSD Program the combustion of biomass fuels can be considered BACT 

for biogenic CO2 emissions at stationary sources until such time as the deferral becomes 

effective. EPA is not revising the guidance at this time. However, commenters may raise these 

concerns about the guidance in the context of individual permitting actions where the guidance is 

applied. The guidance is non-binding and BACT determinations made on a case-by-case basis 

may reflect consideration of additional information. As stated in the March 2011 interim 

guidance document, EPA has not provided a final determination of BACT for any particular 

source, since such determinations can only be made by individual permitting authorities on a 

case-by-case basis after consideration of the record in each case. Upon consideration of the 

record in an individual case, if a permitting authority has a reasoned basis to address particular 

issues in a different manner than EPA recommends in guidance, they have the discretion to do 

so. In addition, BACT determinations based on the reasoning in the guidance may be subject to 

challenge in each permitting action. The unique lifecycle characteristics of biogenic feedstocks, 

and the extent to which characterizing the full carbon cycle of the fuel source is appropriate 

when considering the net atmospheric impact of emissions from a stationary source, are the 

subject of EPA’s ongoing detailed examination of the science and technical issues associated 

with biogenic CO2 emissions. Once that work is complete the Agency intends to undertake a 

rulemaking to establish the treatment of these emissions in the PSD and Title V programs. 
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Comment: Commenter 0065.1 disagreed that indirect impacts should be considered by 

permitting authorities when evaluating the environmental, energy, and economic benefits of 

biomass fuel. The commenter stated that some indirect impacts, such as employment 

opportunities are not relevant to GHG calculations, and those contemplating bio-energy 

investments will naturally balance any social and other non-emissions environmental benefits 

against the GHG emissions costs so that incorporating such ancillary benefits in emissions 

regulations essentially double-counts those unrelated benefits. The commenter acknowledged 

that it may be appropriate to some extent to consider certain federal and state policies, which are 

part of a national strategy to reduce emissions of GHG, as indirect factors. However, the 

commenter believes that EPA inappropriately emphasizes the importance of federal and state 

programs that encourage biomass, but that are unrelated to CO2 emissions, such as indirect 

economic and energy factors that could be used to accept biomass fueled plant practices as 

BACT, because many of these policies were implemented before CO2 emissions became a 

priority of energy programs, and most of these policies have not acknowledged the complexities 

of GHG accounting from biomass-fired and other biogenic sources.

Response: The interim guidance was intended to help permitting authorities establish a basis for 

concluding that under PSD Program the combustion of biomass fuels can be considered BACT 

for biogenic CO2 emissions at stationary sources until such time as the deferral becomes 

effective. EPA is not revising the guidance at this time. However, commenters may raise 

concerns about the guidance in the context of individual permitting actions where the guidance is 

applied. The guidance is non-binding and BACT determinations made on a case-by-case basis 

may reflect consideration of additional information. As stated in the March 2011 interim 

guidance document, EPA has not provided a final determination of BACT for any particular 

source, since such determinations can only be made by individual permitting authorities on a 

case-by-case basis after consideration of the record in each case. Upon consideration of the 

record in an individual case, if a permitting authority has a reasoned basis to address particular 

issues in a different manner than EPA recommends in guidance, they have the discretion to do 

so. In addition, BACT determinations based on the reasoning in the guidance may be subject to 

challenge in each permitting action. 

14.2 Guidance Should be Expanded

Comment: Commenter 0117.1 pointed out that very few of the approximately 16,000 POTWs 

in the U.S. are regulated as major sources due to pollutants other than GHG. If EPA does not 

defer biogenic emissions from PSD and Title V, many new sources could be brought into these 

complex permitting programs. Detailed calculations of biogenic and non-biogenic fossil CO2

emissions at specific units are beyond the scope of the existing published methods and impose 

permitting and administrative burdens on the regulated community and regulatory agencies. No 

peer-reviewed methods have been established for CO2 emissions, and currently available 

methods do not allow for a unit-by-unit calculation. If EPA proceeds with permitting biogenic 

sources, the commenter urged EPA to expand the interim guidance for PSD permitting to allow 

states to conclude that BACT for CO2 emissions from wastewater treatment is simply the 

treatment process itself. This approach is consistent with the approach regarding combustion of 

biomass fuels. 
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Response: This rulemaking defers for a period of three years the application of the PSD and 

Title V programs to biogenic CO2 emissions from stationary sources. This includes the BACT 

requirement where GHG emissions, not counting biogenic CO2, are below 75,000 TPY CO2e. 

As noted in the preamble, the definition of biogenic CO2 emissions includes CO2 emissions from 

wastewater treatment. Since the value of additional guidance is lessened while the deferral is 

effective, EPA believes its resources are best focused on the study and subsequent rulemaking 

rather than developing guidance for additional types of sources. During this deferral period, 

EPA is conducting a detailed examination of the science and technical issues associated with 

accounting for biogenic CO2 emissions. Once that work is complete the Agency intends to 

undertake a rulemaking to establish the treatment of these emissions in the PSD and Title V 

programs. If and when it is appropriate after these actions are completed, EPA will consider 

updating or revising BACT guidance. In the meantime, EPA notes that methods for calculating 

emissions of biogenic CO2 from wastewater treatment facilities are described the December 2010

methodology “DRAFT - Greenhouse Gas Emissions Estimation Methodologies for Biogenic 

Emissions from Selected Source Categories: Solid Waste Disposal, Wastewater Treatment,

Ethanol Fermentation.”2

Comment: Commenter 0101.1 noted that EPA’s PSD regulation also requires the applicant to 

perform an Additional Impact Analysis. As an alternative to BACT, EPA could develop 

guidance for considering fuel sources and associated climate effects in this context.

Response: The additional impacts analysis (40 CFR 52.21(o); 40 CFR 51.166(o) and the BACT 

requirement (40 CFR 52.21(j); 40 CFR 51.166(j)) are based on distinct provisions of EPA 

regulations and the CAA. Although the findings of the additional impacts analysis may inform 

the consideration of “environmental impacts” in the BACT analysis, EPA does not believe 

applicable legal authorities give EPA the discretion to treat the additional impacts analysis as an 

alternative to the BACT requirement. 

14.3 Agree BACT is Biomass

Comment: Commenters 0087.1, 0070.1, and 0023C supported the concept of EPA guidance 

laying out credible scientifically sound accounting methodologies that take into account the 

carbon debt associated with burning biomass for energy to assist state permit writers with BACT 

determinations for biogenic emissions, prior to the time that biogenic CO2 emissions are 

excluded from coverage under the PSD program. Several commenters (0070.1, 0087.1, 0117.1, 

0023C) agreed that BACT for biogenic CO2 emissions at stationary sources is simply the 

combustion of biomass fuels.

Response: As stated in the March 2011 interim guidance document, EPA has not provided a 

final determination of BACT for any particular source, since such determinations can only be 

made by individual permitting authorities on a case-by-case basis after consideration of the 

record in each case. However, for the reasons described in its March 2011 guidance, EPA agrees 

that permitting authorities may be able to support the conclusion that BACT for biogenergy 

facilities is the combustion of biomass fuels alone. The commenters should be advised that the 

 

2 http://www.epa.gov/ttn/chief/efpac/esttools.html
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March 2011 guidance applicable to bioenergy facilities is interim guidance pending completion 

of further analysis by EPA in accordance with the process described in the deferral rule.

Comment: Similarly, commenter 0087.1 encouraged EPA to revise the guidance to state more 

clearly that utilization of biomass fuel usually will be sufficient to constitute BACT for CO2. The 

commenter was concerned that EPA’s Guidance document does not make the case for that 

conclusion as clearly as it should, and provided an example supporting this statement. 

Specifically, the commenter noted EPA’s “top-down” policy is not required by any statute or 

regulation, and EPA should not adhere slavishly to that procedure if it really does not fit well 

with the considerations for determining BACT for bioenergy facilities.

Response: EPA is not revising the guidance at this time. The guidance is non-binding and 

BACT determinations made on a case-by-case basis may reflect consideration of additional 

information. Upon consideration of the record in an individual case, if a permitting authority has 

a reasoned basis to address particular issues in a different manner than EPA recommends in 

guidance, they have the discretion to do so. The commenter thus has the opportunity to supply 

information to permitting authorities that it believes makes the case more clearly than EPA’s 

guidance that biomass is BACT for a particular stationary source. 

Comment: One commenter (0140.1) stated that biomass should be considered BACT as a 

matter of policy until the deferral is final. The fact that EPA has issued Biomass BACT 

Guidance highlights that, until the deferral is finalized, biomass facilities may still be subject to 

EPA’s PSD and Title V programs with respect to CO2 emissions. Consistent with EPA’s 

Biomass BACT Guidance, proposed biomass facilities or major modifications to biomass 

facilities that are permitted before the deferral is finalized should not have to complete BACT 

analyses if CO2 emissions exceed threshold permitting levels.

Response: EPA does not believe applicable statutes and regulations authorize the approach 

suggested by this commenter. Until the amendements to EPA regulations reflected in this rule 

are final and effective, biogenic CO2 emissions are included among the GHG pollutant that is 

subject to regulation. Thus, a BACT analysis for GHG should continue to be conducted where a 

source has the potential to emit 75,000 tpy CO2e or more when including biogenic CO2

emissions in the calculation. While EPA’s guidance provides reasoning that may be used to 

simplify a BACT analysis for GHG at a biogenergy facility, the guidance does not eliminate the 

requirement to complete such an analysis for GHG where applicable under regulations in effect 

at the time a permit is issued. As stated in the March 2011 interim guidance document, EPA has 

not provided a final determination of BACT for any particular source, since such determinations 

can only be made by individual permitting authorities on a case-by-case basis after consideration 

of the record in each case. 

14.4 Disagree BACT is Biomass

Comment: Commenter 0030 disagreed that BACT for biogenic CO2 emissions at stationary 

sources is simply the combustion of biomass fuels. Commenter 0030 stated that the result would 

be to have more large coal plants converting to biomass combustion, requiring very large 

quantities of “biomass” to operate.
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Response: Commenters may raise points such as this in context of individual permitting actions

where the guidance is applied. The guidance is non-binding and BACT determinations made on 

a case-by-case basis may reflect consideration of additional information. As stated in the March 

2011 interim guidance document, EPA has not provided a final determination of BACT for any 

particular source, since such determinations can only be made by individual permitting 

authorities on a case-by-case basis after consideration of the record in each case. Upon 

consideration of the record in an individual case, if a permitting authority has a reasoned basis to 

address particular issues in a different manner than EPA recommends in guidance, they have the 

discretion to do so. In addition, BACT determinations based on the reasoning in the guidance 

may be subject to challenge in each permitting action. 

Comment: Commenter 0350.1 stated that EPA has not demonstrated that biomass combustion 

per se constitutes BACT. The commenter stated further that the Bioenergy BACT Guidance 

effectively constitutes “presumptive” BACT. The commenter stated that the Bioenergy BACT 

Guidance advises permitting authorities to presume that biomass combustion is BACT, and if a 

bioenergy facility advances policies promoting bioenergy, then the BACT analysis for CO2 is 

presumed to be satisfied. The commenter noted this conclusion tells permitting authorities 

absolutely nothing about the environmental, economic, or energy impacts of a particular biomass 

fuel or facility. The commenter stated that any such presumption is unlawful, as the requirement

that BACT be conducted on a case-by-case basis is statutory requirement.

Response: The March 2011 Guidance does not change this fundamental requirement that the 

BACT determination be conducted on a case-by-case basis. The guidance provides the outline 

of reasoning that may be used to demonstrate that biomass fuel alone meets the BACT 

requirement for GHG at sources that emit primarily biogenic CO2, but it does not reflect a final 

determination or create a presumption regarding BACT. The Guidance emphasizes that the 

BACT process may include considerations about the direct and indirect impacts of the emissions 

control option or strategy being evaluated. It also highlights the potential economic and energy 

benefits of utilizing biomass, but to apply this rationale. Permitting authorities still need to 

identify the energy and economic benefits of utilizing particular biomass feedstocks that support 

the type of policies promoting their utilization described in the guidance. The ultimate decision 

about BACT for the proposed facility rests with the permitting authority, not with the facility or 

with EPA. The determination about whether or not the proposed facility meets certain objectives 

with respect to environmental, economic, and energy impacts is thus made on a case-by-case 

basis, by the particular permitting authority.

Comment: Commenter 0118.1 believes that BACT analyses for GHG emissions should include 

wind, solar, geothermal, energy conservation, increased energy efficiency, and seasonal thermal 

energy storage.

Response: Commenters may raise points such as this in context of individual permitting actions 

where EPA guidance is applied. The guidance is non-binding and BACT determinations made 

on a case-by-case basis may reflect consideration of additional information. As stated in the 

March 2011 interim guidance document, EPA has not provided a final determination of BACT 

for any particular source, since such determinations can only be made by individual permitting 

authorities on a case-by-case basis after consideration of the record in each case. Upon 

consideration of the record in an individual case, if a permitting authority has a reasoned basis to 
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address particular issues in a different manner than EPA recommends in guidance, they have the 

discretion to do so. EPA notes that the ultimate decision about BACT rests with the permitting 

authority, which is free to include whatever considerations at Step 4 it deems appropriate.

Comment: Commenter 0128.1 noted that certain language (see EPA-HQ-OAR-2011-0083-

0128.1) from the interim guidance to states does not mean that use of any type of biogenic fuel 

should be considered BACT. The commenter also expressed concern that EPA’s supplemental 

guidance to states provides inadequate bases for states to proceed with the BACT determination 

process. The commenter noted that the guidance will confuse and deter states from considering 

BACT. The commenter asserts that the broad nature of this guidance creates a slippery slope for 

energy developers and regulatory agencies to side-step appropriate CAA review.

Response: The interim guidance provides the outline of reasoning that may be used to 

demonstrate that biomass fuel alone meets the BACT requirement for GHG at sources that emit 

primarily biogenic CO2, but it does not eliminate the need for a BACT analysis for GHG and the 

application of independent judgement by permitting authorities. The guidance is non-binding 

and BACT determinations made on a case-by-case basis may reflect consideration of additional 

information. Upon consideration of the record in an individual case, if a permitting authority has 

a reasoned basis to address particular issues in a different manner than EPA recommends in 

guidance, they have the discretion to do so. EPA notes that the Guidance is based on past 

Guidance documents, including the November 2010 GHG Permitting Guidance whiche was 

revised in March 2011. While these documents do not and cannot resolve every question, EPA 

believes this body of guidance material is, on the whole, helpful to permitting authorities. 

Comment: Commenter 0125.1 asked that EPA modify its interim guidance and future rules to 

make it clear that direct combustion of biomass that can best be used for higher value, 

environmentally-friendly products (such as crude tall oil and crude sulfate turpentine) is not 

BACT for CO2 emissions.

Response: EPA will consider this point as it develops additional rules and guidance. 

14.5 Biomass Fuels Alone

Comment: Commenter 0101.1 stated that the current PSD program could be used to control 

emissions from biomass projects without modification. At a minimum, BACT analyses of 

control strategies that address direct emissions from facilities, such as energy efficiency 

measures, should be required, as is standard practice for fossil fuels.

Response: EPA notes that energy efficiency is an option for inclusion in the set of control 

options in the BACT analysis at Step 1 for all facilities. EPA agrees that this should become 

standard practice for all facilities, and notes that the Bioenergy BACT Guidance does not intend 

to remove energy efficiency as a control option for bioenergy facilities. Although the guidance 

provides a rationale that may support eliminating this option in the case of this type of facility, 

the guidance is non-binding and BACT determinations made on a case-by-case basis may reflect 

consideration of additional information. Upon consideration of the record in an individual case, 

if a permitting authority has a reasoned basis to address particular issues in a different manner 

than EPA recommends in guidance, they have the discretion to do so.
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14.6 Step 4 - Energy, Environmental, and Economic Impacts

Comment: Commenter 0350.1 stated EPA’s proposed expansion of the Step 4 analysis is 

unprecedented and unlawful. The commenter stated that EPA proposes that the Step 4 inquiry be 

used to avoid the necessity for analysis in the first place. The commenter further noted that, in 

essence, EPA counsels permitting authorities to conduct a rigged analysis that substitutes 

preconceived policy judgments for pollution control technologies and ignores the environmental, 

economic, and energy drawbacks of widespread biomass energy generation. The commenter 

then stated the real purpose of EPA’s proposal, to create a de facto exemption from real BACT 

analysis for bioenergy facilities that cannot avail themselves of the broader exemption in the 

proposal, is as unlawful as it is obvious.

Response: The commenter does not demonstrate there is any regulatory or statutory provision 

that restricts EPA’s ability to offer guidance on how to interpret the term “energy, 

environmental, and economic impacts” in the context of the BACT provisions. The interim 

guidance provides the outline of reasoning that may be used to demonstrate that biomass fuel 

alone meets the BACT requirement for GHG at sources that emit primarily biogenic CO2, but it 

does not eliminate the need for a BACT analysis for GHG and the application of independent 

judgement by permitting authorities. Nor does the guidance reflect a final determination or 

create a presumption that biomass is BACT for such sources. The Guidance highlights the 

potential economic and energy benefits of utilizing biomass, but to apply this rationale 

permitting authorities still need to identify the energy and economic benefits of utilizing 

particular biomass feedstocks that support the type of policies promoting their utilization 

described in the guidance. EPA notes the November 2010 GHG Permitting Guidance (updated 

in March 2011) recommends that permitting authorities continue to use the Agency’s five-step 

“top-down” BACT process to determine BACT for GHG. The March 2011 interim guidance 

states (p. 42), “In BACT Step 4, the applicant and permitting authority should consider both 

direct and indirect impacts of the emissions control option or strategy being evaluated.” EPA 

and other permitting authorities may take “into account energy, environmental, and economic 

impacts and other costs,” when evaluating a method or fuel as BACT and therefore EPA finds 

that consideration of these impacts in the BACT Step 4. The ultimate decision about BACT for 

the proposed facility rests with the permitting authority. The determination about whether or not 

the proposed facility meets certain objectives with respect to environmental, economic, and 

energy impacts is thus made on a case-by-case basis, by the particular permitting authority.

Comment: Commenter 0138.1 stated that considering biomass as BACT is not justified. Using 

the example of the We Energies Domtar biomass to energy plant in Rothschild, WI, the 

commenter stated that the permitted emission rate from the Domtar biomass boiler with a natural 

gas burner shows how consideration of biomass as BACT is poorly justified, because EPA’s 

argument is that burning waste wood emits no more carbon than is emitted in decomposition, and 

therefore represents no net addition of carbon to the atmosphere. The commenter further states 

that leaving aside the fact that decomposition takes years to decades, while burning is 

instantaneous, no record has been provided to the public that demonstrates that the Domtar plant 

will burn solely “residues” that would “decompose anyway[,]” and the commenter believes there 

is good reason to assume this plant will have to rely on increased whole-tree harvesting to 

provide fuel. The commenter concluded that when a biomass facility does not just burn waste, 
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and instead turns to increased forest harvesting to provide fuel, net emissions are significantly 

increased, and stated that the widely held assumption that harvesting trees for fuel is “carbon 

neutral”, has been disproved by several cited studies.

Response: Commenters may raise points such as this in context of individual permitting actions

where the guidance is applied. The guidance is non-binding and BACT determinations made on 

a case-by-case basis may reflect consideration of additional information. At Step 4 of the fivestep “top-down” BACT process, permitting authorities should consider the relevant 

environmental, economic, and energy impacts of proposed facilities. For biogenergy facilities, 

this analysis should include direct and indirect impacts of the proposed emissions control 

strategies, including consideration of the desired regional energy mix and the available supply of 

the proposed feedstock. 

The unique characteristics of biogenic feedstocks, and the extent to which characterizing the full 

carbon cycle of the fuel source is appropriate when considering the net atmospheric impact of 

emissions from a stationary source, are the subject of EPA’s ongoing detailed examination of the 

science and technical issues associated with biogenic CO2 emissions. As stated in the March 

guidance, the possibility remains that more detailed examination of the science of biogenic CO2

may show that some biomass feedstocks for bioenergy production are de minimus and that other 

may have a significant impact on the net carbon cycle. Thus, EPA’s guidance is interim and 

EPA is finalizing the proposed temporary, rather than a permanent, deferral of PSD requirements 

for biogenic CO2 emissions from such sources at this time. Once the detailed examination of the 

scientific and technical issues associated with biogenic CO2 feedstocks, the Agency intends to 

undertake a rulemaking to establish the treatment of these emissions in the PSD and Title V 

programs.

14.7 Step 4 - Environmental Impacts

Comment: Commenter 0030 noted that CO2 emissions resulting from the harvesting and 

transportation of such large quantities of woody biomass will add substantially to the climate 

impacts of emissions from the facility’s smoke stacks.

Response: As explained in the preamble of the rule, EPA has concluded that it the science of 

biogenic CO2 emissions are sufficiently complex and requires further discussion with partners 

and scientists both inside and outside the federal government, as well as engagement with an 

independent scientific panel, before it can make more qualitative characterizations about 

biogenic feedstocks. Therefore, the complexities of accounting for CO2 emissions from 

biomass-fired and other biogenic sources including identifying unique characteristics of biogenic 

feedstocks and characterizing important considerations for various feedstocks when considering 

the net atmospheric impact of emissions from a stationary source are the subject of EPA’s 

ongoing detailed examination of the science and technical issues associated with accounting for 

biogenic CO2 emissions. Once that work is complete the Agency intends to undertake a 

rulemaking to establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0350.1 stated EPA’s guidance for assessment of environmental impacts 

is deeply problematic and deviates from past practice by suggesting that the analysis consider the 

effects of CO2 emissions. The commenter stated that EPA’s statement that production of 
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biomass entails carbon sequestration does not mean that combustion of biomass entails carbon 

sequestration, because burning biomass does not by itself guarantee future land-based 

sequestration. The commenter noted that EPA’s land-based BAU sequestration baseline is 

underdeveloped and needs to be far more robust, to include effects of policy action and 

incentives on forest and land management, to account for short-term climate impacts from 

combustion of materials that would otherwise decompose over time, and to account for lost 

capacity for additional sequestration for biomass removal and combustions. The commenter 

stated EPA’s skeletal “baseline” proposal does not seem to consider lost sequestration capacity at 

all. The commenter noted that EPA’s conclusion that certain biomass feedstocks have negligible 

climate impacts lacks scientific support and cannot be used to justify a determination that 

burning feedstocks constitutes BACT. The commenter noted that the Bioenergy BACT 

Guidance ignores wider environmental impacts such as the resulting increased demand for wood 

biomass fuel that affects forest and land management, degrades forest habitat, results in more 

aggressive logging operations that degrade water quality, and results in conventional pollutant 

emissions from biomass facilities that affect human health. The commenter stated that EPA 

advises permitting authorities to consider only the purported benefits of biomass energy 

generation and none of the drawbacks. The commented noted that a BACT analysis should 

include an honest assessment of the environmental consequences of any particular control 

technology, however the Bioenergy BACT Guidance rigs the game, sending permitting 

authorities on an outcome-oriented path toward a preordained conclusion. 

Response: The commenter illustrates the complexities that have motivated EPA’s decision to 

study this important issue further and how the complex nature of this analysis will increase the 

burden on permitting authorities to address this issue in the context of individual permitting 

decision. 

The guidance is non-binding and BACT determinations made on a case-by-case basis may 

reflect consideration of additional information. EPA has previously said that Step 4 includes 

both positive and negative impact considerations. In the March 2011 guidance, EPA emphasized 

that “the environmental impacts analysis in Step 4 should concentrate on impacts other than 

direct impacts due to emissions of the regulated pollutant that is the subject of the BACT 

analysis” (page 18). This includes possible consideration of a variety of environmental impacts, 

such as solid or hazardous waste generation, discharges of polluted water from a control device, 

and emissions of other pollutants subject to NSR or air toxics. 

EPA has recognized a permitting authority is not limited to evaluating the impacts of only the 

“top” or most effective technology but can assess the impacts of all technologies under 

consideration. This approach may include an evaluation of the energy, environmental, and 

environmental benefits of all options under consideration without explicitly eliminating options 

based on adverse impacts. For biomass facilities, the Step 4 analysis may include direct and 

indirect impacts of the proposed facilities, such as including consideration of the desired regional 

energy mix and the available supply of the proposed feedstock. 

As explained in the preamble to the rule, EPA concluded that it the science of biogenic CO2

emissions are sufficiently complex and requires further discussion with partners and scientists 

both inside and outside the federal government, as well as engagement with an independent 

scientific panel, before it can make more qualitative characterizations about biogenic feedstocks. 
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Therefore, the complexities of accounting for CO2 emissions from biomass-fired and other 

biogenic sources including identifying unique characteristics of biogenic feedstocks and 

characterizing important considerations for various feedstocks when considering the net 

atmospheric impact of emissions from a stationary source are the subject of EPA’s ongoing 

detailed examination of the science and technical issues associated with biogenic CO2 emissions. 

Once that work is complete the Agency intends to undertake a rulemaking to establish the 

treatment of these emissions in the PSD and Title V programs. Thus, EPA is unable to provide 

more specific guidance on the types of issues identified by commenter until it completes these 

actions.

14.8 Step 4 - Economic Impacts

Comment: Commenter 0350.1 stated EPA deviates from past practice in recommending that 

permitting authorities consider “indirect” economic impacts or the “potential economic benefits”

of bioenergy generation, and EPA does not explain why such analysis is appropriate for 

bioenergy facilities when it has not been appropriate for any other type of facility. The 

commenter went on to state that these objectives, goals, and policy judgments related to biomass 

have nothing to do with whether the choice of any particular facility to burn biomass will have 

any particular economic impact. The commenter stated that the Step 4 analysis should be 

concerned with establishing the cost-effectiveness of pollution control measures, not with 

advancing unrelated goals and objectives, and the commenter stated that policy judgments have 

no place in BACT analysis.

Response: The commenter does not demonstrate that the term “economic impacts” cannot be 

interpreted to incorporate additional considerations beyond those previously emphasized in prior 

EPA guidance. 

Under Step 4 of the top-down BACT analysis, permitting authorities consider the economic, 

energy, and environmental impacts arising from each option remaining under consideration, and 

this may include potential economic benefits under the circumstances described in the guidance. 

Given the case-by-case nature of the BACT analysis and the importance of considering impacts 

on the local environment and community (including in this case the availability of employment 

opportunities generated within a particular region or community by the utilization of biomass 

fuels), EPA believes this flexibility provided for permitting authorities for deciding how best to 

weigh the trade-offs associated with a particular emissions control option continues to be 

appropriate when evaluating BACT for GHG.

14.9 Step 4 – Energy Impacts

Comment: Commenter 0350.1 stated EPA advises permitting authorities to “broaden the scope”

of energy impacts analysis beyond what has traditionally occurred at Step 4, EPA recommends 

that permitting agencies substitute policy judgments for analysis under Step 4, and stated that 

this EPA policy-driven guidance will skew the analysis away from other renewable fuels. The 

commenter noted that making a policy judgment in favor of a carbon-intensive, low-efficiency, 

and highly polluting biomass facility could have the effect of foreclosing a far cleaner and less 

carbon-intensive alternative. The commenter stated that by focusing solely on the purported 
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benefits of biomass energy generation, and by resolutely ignoring any possible drawbacks, EPA 

precludes any real analysis of indirect energy impacts.

Response: EPA has previously said that Step 4 includes both positive and negative impact 

considerations. The guidance is non-binding and BACT determinations made on a case-by-case 

basis may reflect consideration of additional information. The interim guidance provides the 

outline of reasoning that may be used to demonstrate that biomass fuel alone meets the BACT 

requirement for GHG at sources that emit primarily biogenic CO2, but it does not eliminate the 

need for a BACT analysis for GHG and the application of independent judgement by permitting 

authorities. EPA notes that the ultimate decision about BACT rests with the permitting 

authority, which is free to include the energy, environmental, and economic impact 

considerations at Step 4 that it deems appropriate. Under Step 4 of the top-down BACT analysis, 

permitting authorities consider the economic, energy, and environmental impacts arising from 

each option remaining under consideration, including potential costs and benefits. As explained 

in the March 2011 guidance, this could include consideration of renewable energy policies as 

part of the BACT analysis. If a particular fuel is scarce in the localized area of the proposed 

project, then the scarcity of available fuel for the project might be considered a negative energy 

impact influencing whether it is selected as BACT.
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EPA appreciates the comments received on this topic. Many of the issues raised in these 

comments will be included in EPA’s subsequent work on biogenic CO2 emissions from 

stationary sources, including the Agency’s detailed examination of the science and technical 

issue and any subsequent rulemakings. However, these are comments are outside the scope of 

this rulemaking. 

15.1 Reconciling Accounting Systems: Facility-based Emissions and Landbased Sequestration

Comment: Commenter 0102.1 recommended that EPA revise the language within Section C of 

the proposal, entitled Complexity of Determining Net Atmospheric Impact of CO2 Emissions and 

Incorporating This Information Into the PSD and Title V Programs, to more precisely describe 

the land-based and facility-level accounting systems that EPA intends to incorporate into PSD 

determinations, and commenter 0260 urges EPA to provide proper accounting for “biomass 

incineration.”

Response: EPA appreciates the commenter’s suggestions and notes the description of 

accounting systems is beyond the scope of this action. EPA plans to address the scientific and 

technical issues involved in developing such an accounting system during the three-year deferral. 

The outcome of this analysis will be reviewed by the SAB, and the public will have further 

opportunity for comment on these accounting issues. In the meantime, EPA has made an effort 

to clarify the text in Section C in the final rule. 

Comment: Commenter 0082.1 stated that EPA’s authority is limited to regulating impacts of 

U.S. GHG emissions on the global concentrations. Given this limitation on jurisdiction relative 

to a global problem, the commenter suggested that it is practical to use a national scale for 

assessments and stated that EPA is improperly using the Act when attempting to fit the facilityscale PSD program to a global problem. Commenter 0095.1 stated that the only reasonable and 

scientifically defensible approach to assessing the CO2 impacts of using biomass as fuel for 

electricity production is to compare biomass-related CO2 emissions and sinks on at least a 

national scale. The commenter believed that only at such a scale is forest health and volume 

relevant to atmospheric concentrations of CO2, and smaller-scale assessments simply ignore the 

relevant information and the realities of forest management and biomass use, including the wide 

variety of geographic sources of and types of biomass used by any given facility. The commenter 

also stated that the only consistently produced, reliable data are assessed at the national scale. 

Along similar lines, commenter 0078.1 also stated EPA should analyze biogenic emissions on a 

national scale. 

Response: EPA recognizes the importance of the spatial scale and will consider it carefully in 

our review of the scientific and technical issues related to accounting for biogenic CO2

emissions.

Comment: Commenter 0086.1 stated that biogenic emissions are purposefully and 

appropriately allocated to the land use inventory and reasoned that otherwise the carbon uptake 
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must also be credited to the biomass user and the biofuel producer (resulting in an emissions 

factor of zero in any event), though the land-use changes may not be accurately depicted. The 

commenter stated, policies expressly addressing land use will have an actual and direct influence 

on management decisions to reduce land use changes. Those management decisions will 

influence emissions associated with the land use inventory and result in real reductions of GHG 

emissions from that sector. The commenter argued that if these emissions are included in the 

PSD program, it could influence biomass users to continue to use fossil fuels undermining clear 

and important national energy and national security policies. Commenter 0082.1 also explained

that the CAA does not direct or authorize EPA to regulate land use.

Response: EPA will consider these issues carefully in our review of the scientific and technical 

issues related to accounting for biogenic CO2 emissions.

Comment: Commenter 0101.1 stated, if EPA decides to limit BACT analyses for biomass 

projects to direct emissions from facilities, then EPA should develop another regulatory strategy 

to address net impacts of biomass combustion on global warming. Furthermore, the commenter

argued that, use of biomass as fuel has atmospheric effects unaddressed by simply quantifying

direct flue gas emissions, such as avoiding decomposition emissions. The commenter suggested 

that since net impacts of biomass projects are hard to quantify, and time consuming, EPA should 

work with industry and state agencies to develop guidance that ensures that carbon cycle impacts 

are considered, but also allows flexibility to permitting authorities to limit the analysis to fuels 

that are truly available for use at a particular project.

Response: EPA will consider these issues carefully in our review of the scientific and technical 

issues related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking 

to establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0055.1 directed EPA’s attention to the commenter’s recent research 

results associated with biogenic CO2 emissions from stationary sources. The commenter listed a 

link for additional details but the listed reference was not attached. The methodology is based on 

the elaboration of Impulse Response Functions to predict atmospheric decay of CO2 emissions 

from biomass combustion. The contribution of those emissions to global warming is measured 

with an index, the GWPbio, which is suitable to be adopted in GHG accounting and balances. 

The value of this index ranges between 0 and 1 (so that the climate impact of biogenic CO2 is 

never higher than CO2 from fossil fuels) and is to be multiplied by the direct CO2 emissions from 

biomass combustion (occurring at plant). Since this index is expressed as a function of the 

rotation period of the biomass, the results can be routinely applied to CO2 emissions from 

combustion of all the different biomass species, from annual row crops to slower growing boreal 

forest.

Response: EPA thanks the commenter for the reference to this work, and will review the 

research as part of our review of the scientific and technical issues related to accounting for 

biogenic CO2 emissions.

Comment: Commenter 0111.1 disagreed with EPA’s assessment of the appropriate carbon 

cycle timeframe. The commenter stated that the earth’s carbon cycle is continuous, occurs 

across the globe, and that the previous effect of vegetation growth and sequestration should not 
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be discounted. Emissions should be analyzed from a system level. However, EPA appears to be 

pursuing a carbon debt approach with atmospheric impact timeframes of 10-15 years. An 

accounting model that arbitrarily decides a single location’s starting point for biogenic emissions 

ignores the continuous and system-wide cycle of biomass growth and carbon sequestration. The 

commenter believes that it is premature to reverse biomass carbon neutrality conclusions based 

upon a new accounting methodology. 

Response: EPA will consider temporal scales carefully in our review of the scientific and 

technical issues related to accounting for biogenic CO2 emissions. 

15.2 Complexity in Accounting for Land-based Sequestration

Comment: Commenter 0146 stated that carbon accounting should reflect that the carbon cycle 

is continuous over time. The commenter believed that the carbon debt-dividend accounting 

method is flawed, as it establishes an arbitrary starting point for a continuous cycle. The 

commenter cited a study that concluded the carbon cycle encompasses all recurring plant growth, 

is constantly in flux and cannot be arbitrarily constrained by time and space. The commenter 

further argued that carbon accounting should be at the national scale rather than at the stand or 

plot scale. Since forests are managed across the landscape, not on individual plots, the carbon 

stock changes need to emulate the way forests are managed. The commenter suggested using the

Forest Inventory & Analysis (FIA) data base since EPA relies on it for its annual inventory of 

U.S. greenhouse gas emissions and sinks.

Response: EPA will consider these comments carefully in our review of the scientific and 

technical issues related to accounting for biogenic CO2 emissions. 

Comment: Commenter 0049.1 stated EPA has two concerns: understanding the carbon cycle in 

biomass incineration, and whether our forests have a sustainable supply of biomass for 

incineration. The commenter noted concerns that whole-tree incineration is unsustainable in 

Tennessee. The commenter stated that existing biomass supply studies are unrealistic, and cited 

several reasons, including: supply, rapid land use changes, limits of sampling design, changing 

markets, limited sustainable time limits, logging residue, demand exceeds supply of logging 

residue, competition, upward price movement, and chip mills (see docket letter for additional 

details).

Response: EPA will consider the dynamics of biomass supply in our review of the scientific and 

technical issues related to accounting for biogenic CO2 emissions. 

Comment: Commenter 0023C stated that EPA should measure forest carbon change at the 

national scale. The commenter argued that restricting forest carbon accounting to local areas and

specific timeframes places arbitrary limits on the carbon cycle that distort the forest carbon 

picture. The commenter stated that such distortions had been used to declare that forest biomass 

combustion adds more overall carbon to the atmosphere than coal combustion. The commenter 

stated that the “carbon debt” approach where the carbon cycle is assumed to begin at the time of 

harvest, is arbitrary, because, (i) it ignores the carbon removed through the atmosphere through 

tree growth prior to the time of harvest, and (ii) it ignores that the harvest is only occurring on 

one part of the total forest landscape that continuously removes carbon. Therefore, the 
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commenter urged EPA to avoid arbitrarily declaring a beginning point for the carbon cycle and 

instead to measure changes in carbon stocks at regular intervals to determine net carbon change.

Response: EPA will consider spatial and temporal scales in our review of the scientific and 

technical issues related to accounting for biogenic CO2 emissions.

Comment: Commenter 0023D stated that the basic carbon cycle holds true regardless of time or 

scope. However, biomass carbon neutrality accounting is a function of both time and scope of 

analysis, which must be analyzed on a basis broader than a single plot analysis, where the area of 

review is defined as the forested acreage required to feed a utility boiler for one year and the 

analysis reviews how long it would take for the biomass use to grow back. Since the generating 

facilities obtain biomass from a variety of different sources that constantly change (mostly wood

that would not have been used for other purposes and wood waste), the commenter recommends 

EPA to consider carbon neutrality on a real world basis and also recommends EPA consider 

carbon stocks nationally as the U.S. Forest Service does through its FIA program.

Response: EPA will consider system boundaries, and spatial and temporal scales in our review 

of the scientific and technical issues related to accounting for biogenic CO2 emissions.

Comment: Commenter 0052.1 stated that issues that arise when attempting to reconcile facilitybased emissions with land-based sequestration do not exist when the biogenic carbon cycle is 

examined at the national level. The commenter indicated that forest growth has exceeded 

harvest for years, resulting in a 50% increase in the national average of standing volume of wood 

per acre since 1952 and the average volume per acre has almost doubled during that same period 

in the Eastern United States. The commenter emphasized use of USDA FIA data for tracking 

changes in national carbon stocks, and further argues that the carbon cycle is a continuum and 

cannot be arbitrarily constrained in time and space. The commenter cited some of the natural 

causes such as, the bark beetle epidemic in the western United States and hurricanes resulting in 

an unavoidable “pulse” of CO2 or “dip” in carbon stock over several years, and further argues 

that the biological reality of tree growth makes plot- or stand-specific considerations unrealistic 

and impractical. The commenter claimed, forests are managed as systems across a landscape, 

not on an individual plot-by-plot basis, and the commenter referenced a study of a forwardlooking perspective that has been used for decades in many forestry projection models in which 

future expectations are built into management decisions. This forward-looking type of

management assumes that net biomass growth and corresponding atmospheric CO2 sequestration 

will precede the use of biomass for energy or manufacturing.

Response: EPA will consider spatial and temporal scales in our review of the scientific and 

technical issues related to accounting for biogenic CO2 emissions.

Comment: Commenters 0059.1 and 0062.1 stated that many landfills can be considered carbon 

neutral, or even an overall “anthropogenic sink” of GHG when taking into account both the 

carbon storage capability along with highly efficient landfill gas collection and destruction. 

According to calculations undertaken by commenter 0062.1, the amount of carbon sequestered in 

the commenter’s landfills for the 2009 calendar year: (1) is 2.5 times greater than the biogenic 

GHG emissions from these landfills; (2) represents 96 percent of the anthropogenic GHG 

emissions from these landfills; and (3) represents 70 percent of the combined biogenic and 
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anthropogenic GHG emissions from these landfills. The commenter recommends that carbon 

sequestration must be subtracted from total GHG emissions for any PSD analysis of a landfill’s

potential to emit. Similarly, in analyzing the potential to emit GHG from an MSW WTE plant, 

the biogenic CO2 emissions should be subtracted from the total CO2 emissions thus maintaining 

consistency with the renewable status of the electricity produced from combusting biogenic 

components of MSW.

Response: EPA will consider carbon sequestration in landfills in our review of the scientific and 

technical issues related to accounting for biogenic CO2 emissions.

Comment: Commenter 0065.1 stated that an accounting system that seeks to reconcile facilitybased emissions with land-based sequestration will need to consider spatial and temporal scale. 

The regions over which carbon intensity factors are calculated should be determined by area with 

relatively uniform ecosystem type and management practices. Whatever the geographic scope, 

the accounting should be based on change relative to a without-biomass-use baseline rather than 

using carbon present in a fixed year as a baseline. If regional carbon stocks are trending upward, 

and intensified use for biomass energy deflects that trend downward, then biomass energy use 

will cause a net increase in atmospheric greenhouse gases. Since climate change is a global 

phenomenon and CO2 is a global pollutant, the geographic source of material should be 

irrelevant, so factors may also need to be developed for imported materials. This approach would 

set a useful precedent for European countries that currently do not accurately account for the 

GHG impacts of importing U.S. wood for energy use.

In regard to the temporal scale, some biomass facilities increase the harm from GHG in the short 

run even when they offset that harm in the longer run. The harm associated with generating new 

emissions today may take decades to mitigate as gases are reabsorbed through natural growing 

cycles. Thus, EPA should be explicit about how it balances the near-term harm against potential 

long-term net benefits. The commenter recommends that EPA require biomass projects to 

demonstrate through a careful life-cycle analysis that they would result in lower cumulative net 

GHG emissions within 20 years compared to the energy source they replace or compete with.

Response: EPA will consider system boundaries, spatial and temporal scale, and 

imports/exports in our review of the scientific and technical issues related to accounting for 

biogenic CO2 emissions.

Comment: Commenter 0074.1 stated on the issue of spatial and temporal scale, that though 

forest carbon cycle is best measured on a national, long-term time scale, choosing appropriate 

time and geographical scale to measure biomass emissions is an important policy question. The 

commenter argues that any attempt to account for CO2 fluxes at a smaller spatial scale would 

ignore the realities of the forest products industry and create arbitrary boundaries that distort the 

forest products market. Therefore, the commenter urged EPA to select an accounting system that 

reflects the national scale on which the carbon cycle and forestry industry operate. Furthermore, 

the commenter argued that forest carbon sequestration and emission occur simultaneously and 

the quantity of carbon emitted during combustion is offset by the quantity of carbon sequestered 

through the continuous growth of trees on forested land throughout the United States. To capture 

the continuous nature of the carbon cycle, an accounting system must measure changes in the 

national carbon stocks at regular intervals to determine net changes in carbon stocks rather than 
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implementing a debit and credit system for individual tracts of land. The commenter believed 

that this approach would be consistent with national inventory approach applied by the U.S. 

Forest Service that has demonstrated a net increase in overall forest carbon stocks in the U.S. of 

nearly 50% over the second half of the 20th Century, which has come during a time of 

unprecedented increase in demand for forest products for home construction, consumer goods, 

and energy. The commenter asserted that accounting systems that incorporate large spatial 

scales and continuous temporal scales consistently demonstrate that biomass provides a carbon 

neutral energy supply with significant carbon benefits through displaced fossil fuel consumption. 

At the same time, the commenter critiqued the recent studies which challenge carbon neutrality 

of biomass energy, such as Manomet study (Walker et al. 2010). The commenter argued the 

Manomet study was based on an inappropriate stand-based spatial scale that ignored the reality 

of rotational harvesting, and arbitrarily “began” the carbon cycle at the time of harvest to 

emphasize emissions over sequestration. Though these studies are based on the same scientific 

principles rooted in the carbon cycle, they reach different results due to the policy preferences 

that inform the accounting methods. The commenter suggested, rather than assuming a lack of 

scientific consensus, EPA must carefully assess the policy preferences underlying the biomass 

debate and choose those preferences which reflect both sound science and the realities of the 

forestry industry, and are consistent with the government’s renewable energy policy.

Response: EPA will consider these interconnected issues in our review of the scientific and 

technical issues related to accounting for biogenic CO2 emissions, as well as in the subsequent 

rulemaking to establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0079.1 stated that accounting approaches for biogenic CO2 emissions 

need to be clearly defined and implementable. The complexity of the PSD permitting program is 

primarily not in the permitting process, but in the determination of applicability, which includes 

detailed requirements for calculating baseline emissions, projecting future emissions, 

documenting such calculations, and tracking emissions after each change. The commenter 

recommended that any system that EPA adopts to account for biogenic CO2 emissions should be 

as simple as possible and should establish categorical exclusions. EPA can justify such 

exclusions based on a general analysis, such that there is no reason for any particular facility to 

justify that its particular biogenic CO2 emissions should be excluded. Contingent categorical 

exclusions are also problematic because they could create enforcement implications for past 

actions of sources if EPA trips the contingency.

Response: EPA understands the need to develop an accounting system that is transparent, as 

well as easy to understand and implement. We will consider this issue in our review of the 

scientific and technical issues related to accounting for biogenic CO2 emissions, as well as in the 

subsequent rulemaking to establish the treatment of these emissions in the PSD and Title V 

programs. 

Comment: Commenter 0082.1 suggested that EPA’s study scope recognizes a global 

concentration concern bounded by a national jurisdiction. The commenter cautioned EPA that, 

despite broad consensus with respect to the underlying scientific principles, policy preferences, 

EPA must be careful not to treat assumptions and policy arguments as scientific facts. Instead, it 

should focus on the clearly established science of the carbon cycle and then develop a policy that 

reflects the realities of U.S. forestry and the forest products sector and is consistent with the 
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Administration’s policy on renewable energy. In addition, the commenter encouraged EPA to 

consider additional data and information that has been and will be submitted to the docket since 

the deadline for submissions to EPA’s CFI has passed. The commenter also provided references 

of various studies that demonstrated land-use and land-cover change do not negatively impacted 

by biofuels and no impact on soil carbon with additional biomass harvesting. As revealed by 

Powers et al. (2004) on a Long Term Research Productivity study, the post-harvest carbon 

increased at all depths across all studies regardless of whether or not surface organic matter had 

been removed. The authors concluded that “soil inputs following disturbance depend less on 

decomposition of surface residues and more on the decay of fine roots that remained from the 

previously harvested stand.” The commenter stated as EPA develops and implements its study 

framework and delivers the scope and charge to its assembled expert review panel, the EPA 

should focus on the actual concern and on the relevant scale. In addition, the commenter urged 

EPA to focus its analysis and decisions on the largest scale possible within its jurisdiction, which 

is the national scale inventory. The commenter believes that any attempt to configure an 

accounting system within the perceived constraints of the facility-scale PSD program on a caseby-case basis would result in absurd results.

Response: EPA will consider these interconnected issues in our review of the scientific and 

technical issues related to accounting for biogenic CO2 emissions, as well as in the subsequent 

rulemaking to establish the treatment of these emissions in the PSD and Title V programs. EPA 

thanks the commenter for the reference to late comments to docket EPA-HQ-OAR-2011-0560 on 

the CFI and we will consider the additional information in our review. 

Comment: Commenter 0086.1 stated that determining applicability of the PSD program is 

already extraordinarily complex and it currently includes detailed requirements for calculating 

baseline emissions, projecting future emissions, documenting such calculations, and tracking 

emissions after a change. The commenter urged that if EPA determines that accounting for 

biogenic CO2 emissions is necessary, any such accounting system should be as simple as 

possible and should establish categorical exclusions, which the EPA could justify based on a 

general analysis, such that there is no reason for any particular facility to justify that its particular 

biogenic CO2 emissions should be excluded. The commenter further stated that EPA should 

only focus on the carbon cycle of the feedstock considered, and not on indirect impacts. 

Regarding the proposal’s discussion of establishing an accounting system, the commenter stated 

that before EPA attempts to identify a method to calculate “the net atmospheric impact..., from a 

stationary source,” EPA must consider whether the carbon neutrality presumption is valid to 

support a “permanent exemption ... for at least some and perhaps all types of feedstocks” and 

urged EPA to focus on the carbon cycle of the particular feedstock being used and thought that 

EPA’s reference to “leakage” as an inappropriate consideration. The commenter argued that 

considering the notion of a feedstock’s direct carbon cycle does not give EPA license to consider 

indirect effects of biogenic CO2 emissions, as those are not from the facility and are beyond the 

control of that facility. Indeed, EPA has not required, nor does it indicate it would require, other 

sources of energy to consider indirect impacts. Therefore, the commenter urged EPA to clarify 

that it is not considering indirect impacts associated with use of biomass or biofuel. The 

commenter reported that with respect to the ethanol industry, increased crop productivity has 

primarily provided the growth in production necessary to meet heightened demand for 

crop‐based feed, food, and fuel, and moving forward, more pronounced gains in productivity 

promise to mitigate the need for large amounts of new agricultural lands. The commenter also 
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stated that the United States has experienced a net increase in forested area and also stated that it 

is only certain “existing agricultural land” that was cleared or cultivated prior to December 19, 

2007 and non‐forested from which planted crops used as feedstock for renewable fuel may be 

used. Therefore, the commenter believed that there are significant safeguards in the RFS2 that 

protect against land conversion to agriculture.

Response: EPA recognizes the importance of these issues and will consider them in our review 

of the scientific and technical issues related to accounting for biogenic CO2 emissions.

Comment: On the timeframe of analysis, commenter 0102.1 stated that the proper timeframe 

for analysis is best defined by the length of the integration period used to evaluate the normalized 

integrated 100-year effects of GHG. The commenter stated, given the emphasis placed in the 

Tailoring Rule on environmental endpoints (normalized integrated radiative forcing using the 

GWP construct), comparability of emissions impacts in relation to environmental endpoints, and, 

finally, their fungibility within the regulatory system, there is no basis for a separate distinct 

integration period for biomass combusted CO2. On the spatial attributes, the commenter 

believed that the resolution of biomass re-growth characteristics at a regional level will be 

sufficient for purposes of PSD applicability. The commenter also cited that this is the level of 

resolution that is applied to the evaluation of forestry stocks in the EPA Greenhouse Gas 

Inventory 1990-2008.

Response: EPA recognizes the importance of these issues and will consider them in our review 

of the scientific and technical issues related to accounting for biogenic CO2 emissions.

Comment: Commenter 0104.1 stated that current PSD accounting regulations require that 

reductions in emissions are only considered in netting calculations with requested increases in 

emissions when those reductions occur at the same source during a “contemporaneous” period. 

The commenter stated that an accounting timeframe in the range of one to three years is 

appropriate and that waiting for emissions to be offset several decades in the future is 

unreasonable. The commenter argued that an annual timeframe is consistent with the statutory 

and historic regulatory approach, as well as it is consistent with the actual lifecycle neutrality of 

perennial crops. A period of three years for achieving carbon neutrality is the upper limit for a 

timeframe given the pressing need for greenhouse gas reductions in the near-term. Furthermore, 

similar to the annual timeframe, it also coincides with the lifecycle neutrality of certain biomass 

feedstocks. The commenter supports an argument by environmental scientists that forests are 

growing and sequestering carbon on the landscape as a whole, including land beyond the fuel 

shed used by a bio-power facility, and that this compensates for the carbon emitted by cutting 

and burning trees. The commenter thought the biogenic carbon accounting approach discussed 

by these scientists which makes the fundamental point that the baseline for unmanaged forests is 

one of continued growth and carbon sequestration, is true for individual stands and whole forests. 

The commenter stated that widening the scope of their accounting approach may make changes 

relatively smaller, but it does not make them absolutely smaller or change this baseline against 

which forest carbon accounting must be conducted. However, the commenter disagreed with 

NAFO’s view on emissions from forest biomass and argued that nothing in NAFO’s “eternal 

carbon cycle” argument acknowledges the considerable acceleration in carbon emissions that 

occurs when biomass is harvested and burned rather than allowing it to complete its lifecycle and 
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decay naturally (a process that takes years, if not decades, and also contributes to long-lasting 

soil carbon pools where carbon is locked up for decades to centuries).

Response: EPA recognizes the importance of these issues and will consider them in our review 

of the scientific and technical issues related to accounting for biogenic CO2 emissions.

Comment: Commenter 0126.1 stated that biomass carbon neutrality accounting is a function of 

the land under consideration. The commenter explained how a “single plot” analysis of biomass 

on a one year basis, is inappropriate and cited the similar conclusion from the National Council 

on Air and Stream Improvement (NCASI) study. The commenter recommended a broader 

based, national level analysis that includes a review of the amount of carbon stocks nationally, as 

indicated by long-accepted tools such as the U.S. Forest Service FIA Program. The commenter 

thought that while there is some risk for biomass power generation from a nationwide analysis, 

since forest stocks could be depleted as a result of unrelated factors such as land conversion, it is 

a more accurate and reasonable approach than an artificial single plot review. The commenter 

also stated that biomass carbon neutrality accounting is complicated by two very important 

factors:

i) Biomass for any specific facility is likely to come from a variety of sources, most or all of 

which will be outside the control of the facility, and those sources likely will change quite 

frequently, which raises the question of how a facility can be responsible for the, “outside 

the fence line” portion of any carbon neutrality accounting. 

ii) It is not possible for the EPA or the facility operator to know what would have been done 

with the biomass materials absent their use for combustion, since typically the majority 

will release near-term emissions from combustion or decay, as trimmings and other 

biomass with little commercial value are often piled for burning or used as mulch.

The commenter stated, that complex carbon neutrality accounting would constitute land-use 

management which is beyond EPA’s statutory authority, and the commenter urged EPA to steer 

clear of such assumptions and instead recognize the need for a broad-scale accounting given that 

the facility-by-facility or single plot approaches are unworkable. 

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

15.3 General Principles

Comment: Commenter 0082.1 stated that accounting systems for GHG emissions should be 

based on CO2e to properly reflect impacts.

Response: EPA disagrees with the commenters seeking expansion of the deferral to CO2e. 

While non-CO2 GHG are produced when biomass is combusted, the level of emissions and 

resulting impact on atmospheric concentrations of these gases are primarily related to the 

feedstock handling and combustion conditions at the specific plant rather than to the source of 

the feedstocks. We finalized this rule as proposed and included only biogenic CO2 emissions for 

this reason, and we note that emissions of non-CO2 GHG are typically a small proportion of the 

total GHG emissions from combustion of biologically based material. Since the non-CO2 GHGs 
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are so small relative to CO2, the deferral of biogenic CO2 emissions will ensure that biomass 

combustion projects will likely not meet the applicability thresholds based on their CH4 and N2O 

emissions alone.

Comment: Commenter 0128.1 stated that EPA should examine assumptions about forest 

sustainability since they are integral to achieving net GHG reductions at “the stack” compliance 

level. The commenter asserted that the ability of biomass energy to achieve carbon neutrality 

will strongly rely on feedstock sources and how they respond to two widely held assumptions: 1) 

that new carbon sequestration from “replacement” forest growth will necessarily always occur 

and not be double counted against other emission sources, and, 2) that the avoidance of assumed 

emissions from wood residue decay is valid across different types of feedstocks. The commenter 

noted that EPA has acknowledged the importance of the first assumption in its interim guidance 

to states and that research indicates that substantial increases in biomass demand will lead to 

much higher intensity of harvests that will strain the sustainability of forest resources. The 

commenter also stated that the second assumption is misplaced because a significant percentage 

of “waste wood” or “wood residues” is absorbed as soil carbon.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Many commenters (0023C, 0023D, 0032, 0074.1, 0083.1, 0087.1, and 126.1) stated 

that approaches such as BAU are arbitrary and difficult to apply in practice, in part because it 

chooses a “beginning point” to a continuous cycle and because it requires unverifiable 

speculation of what would have otherwise been done with the biomass fuel stock. Commenter 

0023C argued that current forest practices yield significant and valuable increases in overall 

forest carbon sequestration that private forest owners provide without any means of 

compensation. Furthermore, the commenter stated that a BAU baseline would arbitrarily take 

these benefits with no return to the forest owner and introduce additional costs to forest 

management, thereby discouraging additional forest sequestration by reducing the value of the 

forests and incenting forest owners to convert the land to more profitable uses. The commenter 

stated that encouraging stronger markets for forest products like renewable energy is a far more 

effective method to increase forest sequestration than a regulatory taking, and commenter 0074.1 

stated that EPA should choose a baseline that addresses whether or not biomass is a carbonneutral energy source. Commenter 0074.1 objected to the BAU concept because it would 

arbitrarily set a trajectory for future changes in forest carbon stocks, but in reality, forest growth

(i.e., carbon cycles) are subject to natural events that may cause a temporary depletion from time 

to time. The commenter also noted that the need to assess all influencing factors under the BAU 

approach makes it needlessly complicated, because this approach assumes that current conditions 

are indicative of a natural level of sequestration, but in reality, humans have actively managed 

forests for centuries, and the current balance between sequestration and emissions is the product 

of a complex milieu of government regulations and market forces that make such a prospective 

policy tool unlikely to accurately predict effects of policy changes. Therefore, the BAU approach 

cannot disaggregate natural levels of forest sequestration from current anthropogenic levels. 

Commenter 0083.1 added that increased market demand for biomass as a fuel stock will provide 

stakeholders with incentives to increase biomass growth rates and volumes; the commenter 
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thought, this trend would further complicate any attempt by EPA to make an accurate projection 

of future BAU levels of sequestration. Commenter 0074.1 also stated that EPA must be careful 

not to set a baseline in a manner that punishes forest owners for past sequestration or mandates 

sequestration in the future. Commenter 0032 added that wood volumes in Southern forests are at 

an all-time high and will likely decrease in the short-term because of forest age class 

distributions. 

Response: EPA will consider the issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Another commenter (0052.1) stated that the concept of BAU, as described by EPA 

in its proposed deferral, simply cannot be used to impose land-based sequestration principles in 

the context of stationary source permitting. Commenters (0052.1 and 0087.1) thought, in 

practice, a BAU approach would function as a cap on utilization of forests so that energy users 

and fiber producers would be required to pay higher prices. The commenters also stated that as a 

trade-exposed sector the forest products industry is less able to pass costs through to customers, 

while the utility sector is able to increase electricity rates to pass through costs to its ratepayers, 

creating an uneven playing field in the fiber markets and putting the forest products industry at a 

distinct disadvantage with potential displacement. Therefore, the commenters urged EPA to 

abandon any attempt to utilize BAU principles.

Response: EPA will consider the issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs.

Comment: Commenter 0087.1 did not support the BAU construct, but stated that if EPA were 

to adopt such a construct, that forests harvested for products, their associated carbon stocks, and 

any residuals and byproducts that are combusted, clearly must be included in BAU baselines. 

The commenter stated that it is unclear from the preamble language whether some level of 

current and projected stand alone biomass based energy (and the forests planted to meet that 

demand) would be incorporated into BAU baseline projections. The commenter expressed

concern that the preamble language is unclear on how the suggested constraint of biomass use to 

BAU levels reconciles with broader national energy policy to increase renewable energy.

Response: EPA will consider the issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0065.1 stated that because BAU predictions are uncertain, and modeling 

for each individual situation is impractical, EPA should consider allowing regulated facilities to 

apply a standardized “carbon intensity factor” that adjusts direct combustion emissions to reflect 

net biogenic CO2 emissions to the atmosphere. EPA should distinguish five categories of woody 

biomass feedstocks that differ in their biogenic CO2 impacts: wood waste (including mill, clean 

construction, and post-consumer waste and urban tree trimmings); logging residues from 

commercial timber operations; fuel reduction thinnings from restoration treatments designed to 
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reduce the frequency or intensity of fire; annual and short-rotation biomass crops; and whole tree 

chips from expanded harvest operations.

We suggest that EPA develop a carbon intensity factor for each of the above five fuel types for 

regions of the country with relatively uniform forest types, product mixes and silvicultural 

practices. The carbon intensity factor would be a value between zero (biogenic emissions cause 

no net increase in atmospheric GHG) and one (all biogenic emissions represent a net increase in 

GHG). Multiplying the carbon intensity factor by the total biogenic emissions from that fuel type 

would yield net biogenic emissions from that source subject to regulatory limits.

A basis for calculating these factors for each of the five fuel types should include:

(1) materials diverted from the waste stream - possible carbon intensity factors near zero –

emissions are the same as or less than the emissions that would have occurred in the 

landfill or decomposition site, given differences in methane emitted;

(2) logging residues from existing commercial operations - carbon intensity factors may be 

low – operations should protect future forest productivity, residual stand and/or advanced 

regeneration, habitat, and water quality);

(3) materials from thinning treatments designed to protect future carbon stocks - these 

materials may be assigned low carbon intensities to the extent that short-term carbon 

losses associated with treatment prevent future carbon losses that otherwise would have 

occurred due to major disturbances such as wildfire;

(4) short-rotation biomass crops harvested on a continuing basis where previous land uses 

maintained similar or lower mean levels of carbon stocks (e.g. cropland), and where 

carbon stocks recover rapidly (less than ten year rotation) - carbon intensities may be near 

zero; however, for biomass crops grown on land converted from higher-carbon uses (e.g. 

mature forest) the intensity factor would be higher; and

(5) materials from dedicated harvesting of live vegetation - rarely if ever “carbon neutral”, 

since the “without-biomass” baseline would store more carbon in forest pools, re-growth 

on the harvested land takes time, and some source lands may experience land use 

conversion that prevents any recovery of carbon; however in most cases intensity factors 

would be less than one.

Because tracking the source of each batch of wood fuel would be burdensome for biomass 

facilities, and batches may have mixed sources, EPA should consider assigning a default factor 

to each facility at the highest carbon intensity associated with feedstock sources in that region. 

Operators could petition for permission to use lower carbon intensity factors based on actual 

documentation. In response, EPA could apply its standard regional factor appropriate to the 

documented source, or use a case-by-case approach.

The commenter notes other similar approaches, such as carbon footprints and carbon neutrality 

factors that can be used to appropriately account for net carbon emissions.

After presenting numerous problems with implementing the BAU construct (summarized in 

previous comments), commenter 0087.1 also suggested that using a feedstock approach as a 

surrogate for the BAU baseline concept approach could help simplify implementation difficulties 

as noted above, but thought it will, by definition, err on the side of excluding “types” or 

“categories” of biomass that could be sustainably used for bio-energy.
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Response: EPA will consider this issue, and the suggested approaches, in our review of the 

scientific and technical issues related to accounting for biogenic CO2 emissions, as well as in the 

subsequent rulemaking to establish the treatment of these emissions in the PSD and Title V 

programs. 

Comment: Commenter 0102.1 agreed with the general principal of excluding BAU emissions 

from PSD applicability determinations, but did not agree with the proposition to include 

emissions increases attributable to changes in market demand following a project. Commenter 

stated that “downstream market effects are notoriously uncertain and difficult to estimate” and 

have never been included in PSD applicability determinations; unless EPA is proposing that 

every fuel be subject to a downstream market demand test, the application of such a test solely to 

biogenic fuels would be unfair and arbitrary.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0102.1 believes that the discussion of general principles could be 

broadened to include a wider array of principles. Isolated to the evaluative framework, the 

commenter believes that the evaluative framework should be physically-based and physically 

realistic; address the relevant environmental endpoint; narrowly relate emission to the relevant 

environmental endpoint and allow the narrow formulation of policy to achieve desired goals; be 

consistent with, and defined in relation to, the underlying biogeochemical processes in play in 

the global carbon cycle; treat biogenic CO2 in a manner that is consistent with the treatment of 

other GHG and GHG emissions sources so as to promote overall efficiency of GHG regulatory 

programs; remove ‘anyway’ emissions from facility totals; allow for offsets where policies lead 

to net carbon storage over the relevant integration period; account for the possibility that, 

through unknowable future land management practices, land-use changes or climate change 

impacts, storage might not be permanent over the relevant integration period.

Response: EPA thanks the commenter for these suggestions about how to evaluate the 

accounting methodology for biogenic CO2 emissions, and will consider them in our review of the 

scientific and technical issues related to accounting for biogenic CO2 emissions. 

Comment: Commenter 0102.1 re-iterated comments previously submitted in response to the 

CFI in September, 2010. This commenter recommends an accounting system that does not 

exclude biogenic emissions but requires PSD applicability calculations that are based on the 

GWP construct. The construct deploys four terms: 

i) instantaneous radiative forcing per unit mass of emission (in watts per square meter) 

ii) integrated 100-year atmospheric retention per unit mass of emission (in ton-years) 

iii) integrated 100-year radiative forcing per unit mass of emitted CO2 (in watts per square 

meter-years) 

iv) a discount factor to account for the possibility that not all sequestered CO2 will remain in 

storage over the time period used for calculation.
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Under the proposed approach, the second term would be adjusted to reflect the benefits of 

biogenic CO2 so that biogenic CO2 would be weighted differently than fossil CO2. The 

commenter stated that this approach provides a realistic measure of 100 year radiative forcing. 

Response: EPA thanks the commenter for these suggestions, and will consider them in our 

review of the scientific and technical issues related to accounting for biogenic CO2 emissions.

Comment: Commenter 0065.1 stated that BACT should require distinguishing between 

facilities that make a national problem worse and those that make it better, because there are a 

large number of studies which conclude that using wood for energy can result in an initial 

“carbon debt” since wood fuels release more CO2 unit of energy than fossil fuels, but the carbon 

debt can be “paid back” if sources use waste wood, woody crops, or thinnings under some 

conditions, or over time through accelerated forest growth, but this widely varies from feedstock 

to feedstock. The commenter is concerned that if EPA adopts the simple premise that use of 

biogenic fuels equals BACT for biogenic CO2, higher ambient concentrations of CO2 (than 

would occur with use of conventional fossil fuels) will result for up to 100 years when the carbon 

debt is paid off. The commenter believes that to determine that some types of biomass have de 

minimis impacts, the EPA must accurately estimate and consider GHG impacts associated with 

each type of biomass.

Response: EPA thanks the commenter for these suggestions, and will consider them in our 

review of the scientific and technical issues related to accounting for biogenic CO2 emissions. 

15.4 Case-by-Case Analysis

Comment: Commenters 0074.1, 0078.1, 0082.1, 0086.1, 0146, 0096.1, and 0125.1 opposed a 

case-by-case approach. Commenters 0074.1 and 0086.1 argued that any attempt to measure the 

net atmospheric impact of the combustion of biomass fuels would necessarily include a difficult 

and complex assessment of sequestration at the harvest site because individual facilities obtain 

biomass from a host of sources. Additionally, Commenter 0086.1 argued that there is no 

scientific model for this approach and supply chain accounting is impractical and unfeasible for 

fungible bioenergy feedstocks. Commenters 0074.1 and 0086.1 also stated that given the sheer 

number of sources involved, a case-by-case analysis would simply be too costly to implement in 

terms of time and resources, adding to the complex and burdensome reporting already required 

of facilities. Furthermore, commenter 0074.1 stated that a case-by-case analysis is unnecessary 

because there is no basis for distinguishing among different types or sources of biomass. In lieu 

of a case-by-case analysis, commenter 0074.1 suggested a monitoring and reporting program for 

all forest owners, regardless of their size, whereas commenter 0086.1 suggested that EPA utilize 

general emission factors and large‐scale models to produce comprehensive national‐level 

emissions estimates, such as those reported in the U.S. GHG Inventory report. Commenter 

0078.1 stated that case-by-case accounting to satisfy a PSD analysis framework is untenable in 

practice and unnecessary given the global nature of GHG concentrations. Commenter 0082.1 

opposed a “case-by-case” approach to PSD applicability for biogenic projects at the local scale, 

because this approach would create unfair economic disparities and potentially conflict with 

existing renewable fuel policies. Commenters 0146, 0096.1, and 0125.1 agreed that case-by-case 

analyses of CO2 emissions would be prohibitively time-consuming and expensive. Commenter 
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0146 stated that it would not give facilities and businesses, and by extension, forest landowners, 

the long-term stability and predictability needed to plan for facilities and sustainable harvests.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

15.5 Categorical Exclusion

Comment: Commenter 0052.1 supported the categorical exclusion, because counting CO2

emissions at the point of combustion is double-counting since land use changes inherently 

include changes in carbon stocks. Additionally, the commenter argues that the recycling 

principle applies to all types of biomass combustion as long as growth exceeds drain. The 

commenter stated that the rationale for the exclusion should be based on accounting at the 

national scale for the growth/drain ratio of biomass at the optimal spatial and temporal scales. 

The commenter suggested that the four geographic regions used by the U.S. Forest Service in its 

FIA National Program might serve as an appropriate alternative to a nation-wide approach. The 

commenter stated, both of these approaches will improve the statistical precision of the 

growth/drain ratios and more accurately account for the fact that mills and utilities obtain fiber 

from fiber basins that cover multiple states. 

Commenters 0032 and 0082.1 stated that a categorical exclusion for all biogenic sources is the 

most appropriate method given the LULUCF inventory. Commenter 0032 stated that current 

efforts to monitor LULUCF carbon flux is the best of the four alternatives provided in the 

preamble text. Commenter 0082.1 believes that the national LULUCF GHG inventory clearly 

shows that there is no evidence on a national scale that CO2 emissions from biomass use will 

exceed the carbon stored in the LULUCF sector. The commenter argued that EPA’s 

incorporation of GHG emissions into the PSD program via the definition of “regulated NSR 

pollutant” does not apply to CO2 emissions from biogenic combustion, as illustrated by the 

LULUCF inventory. The commenter further argued that treating combustion of biomass as 

carbon neutral is scientifically sound since carbon emissions are not increasing in the atmosphere 

and United States carbon stocks are stable or increasing. The commenter stated that since the 

deferral decision is causing uncertainty and delaying biomass energy projects, EPA should 

quickly reverse the inclusion of biogenic CO2 emissions under the permitting programs, and the 

commenter suggested EPA proceed immediately with the study and supplemental rulemaking 

discussed in the proposal. 

Response: EPA agrees that at the national scale, to include CO2 emissions from bioenergy 

combustion in the Energy sector of the Inventory would be double-counting since the LULUCF 

sector already accounts for those emissions. EPA will consider this issue in our review of the 

scientific and technical issues related to accounting for biogenic CO2 emissions, as well as in the 

subsequent rulemaking to establish the treatment of these emissions in the PSD and Title V 

programs. 

Comment: Commenter 0074.1 stated that a categorical exclusion is consistent with policy goals 

since it utilizes a nationwide spatial scale and recognizes that biomass energy is carbon neutral 

because emissions from biomass combustion are balanced by sequestration during forest 
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regeneration. Furthermore, a straightforward categorical exclusion avoids unnecessary 

administrative and compliance costs, and EPA already has experience with this accounting 

method, because it is employed in the annual GHG Inventory program. The commenter further 

stated that such exclusion merely recognizes that biomass carbon is not appropriately regulated 

at the stationary source scale. The commenter added that since forests are already subject to 

numerous state and federal regulatory initiatives, forestry agencies have particular expertise in 

assessing net fluxes, and many of these initiatives promote sequestration.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0086.1 supports the categorical exclusion based on the premise of

carbon neutrality. The commenter stated that changes in carbon stocks due to land use change 

does not in any way obfuscate or change the carbon neutrality of the actual biomass itself. The 

commenter also believes that EPA has ample authority to provide for a categorical exemption for 

all biogenic CO2 emissions.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

15.6 Contingent Exclusion

Comment: Commenters 0032, 0052.1, 0074.1, and 0086.1 did not support the contingent 

exclusion approach. Commenter 0032 stated that the example given for an “added contingency”

is not a sufficient metric to determine the impacts of bioenergy and biogenic sources because 

forest land may change from a carbon sink to a carbon source over the next several decades for a 

variety of reasons that have no relationship to bioenergy (e.g. drought and other climate factors, 

pests, disease, wildfire, changes in age class/structure). The commenter further stated that while 

they agree that new monitoring techniques need to be implemented across a diversity of potential 

feedstocks, the commenter cannot support this accounting approach without a detailed 

explanation of the contingency. Commenter 0052.1 did not support a contingency based 

approach at the state level due to: (a) the diminished statistical precision, (b) the failure to 

capture interstate supply within fiber basins, and (c) the complexity that such an accounting 

approach would pose for companies that operate in multiple states. Commenter 0074.1 

commented that a contingent exclusion would not be sound science or policy because carbon 

fluxes to the atmosphere take place without industrial biomass combustion, such as fluxes 

associated with land use, fires, disease infestations, and powerful storms. The commenter argued 

that this approach will create uncertainty regarding the long term applicability of the exclusion 

and reduce investment in biomass energy, and the commenter provided some examples of why a 

contingent exclusion would be hard to develop and difficult to implement. Commenter 0086.1 

commented that the contingent exclusion approach is inappropriate and unworkable, because it 

would be impossible for EPA to determine whether a particular project changed the carbon flux 

and whether calculated changes will affect climate change. This commenter argued that, while 

agricultural lands have been on the decline in the United States for decades, EPA cannot attribute 

national changes to agricultural lands to the bioenergy or biofuel industry. Commenter 0.0086.1 
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mentioned that the contingent categorical exclusion is also problematic because it could create 

enforcement implications for past actions.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions.

Comment: Commenter 0082.1 suggested the U.S. Forest Service (USFS) and EPA jointly issue 

the national forest inventory on a five year basis to determine whether the forest carbon 

inventory at a national level was stable, increasing, or declining and base a regulatory response 

on that finding. The commenter stated that this alternative approach aligns with the “contingent 

exclusion” approach, would provide a collective incentive for forest managers to ensure that 

forest carbon stocks remain neutral or positive, and it would encourage CAA permittees to 

become partners with forest growers. Additionally, the five-year look-back period is consistent 

with Title V operating permit cycles and with FIA data collection cycles. The commenter also 

believed that this approach would provide some assurance of predictability to permit holders and 

alleviate mill owners from being put in the impossible position of complying with and enforcing 

land use regulations.

Response: EPA thanks the commenter for these suggestions, and will consider them in our 

review of the scientific and technical issues related to accounting for biogenic CO2 emissions, as 

well as in the subsequent rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs. 

Comment: Commenter 0087.1 supported a contingent exclusion based on the national 

inventory because CO2 emissions do not result in local impacts and stated that the national scale 

provides business certainty and a level regulatory playing field for interstate commerce. 

However, the commenter argued forest values (e.g., water quality and habitat) are typically 

assessed and managed at the state, regional and landscape levels as appropriate but that the forest 

carbon cycle (and procurement of biomass fiber) does not fit into state-level geographic 

boundaries. The commenter maintained that policymakers must assess whether the national 

carbon cycle is in balance, rather than inappropriately assessing individual sources and sinks or 

timeframes. The commenter argued that, given the evidence that forest carbon stocks in the U.S. 

are stable or increasing, there is every reason to conclude that the forest carbon cycle in the U.S. 

is achieving net removals of CO2 from the atmosphere. Consequently, biogenic CO2 from 

biomass combustion should be counted as zero.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

15.7 Feedstock-based Approach

Comment: Commenter 0087.1 urged EPA to affirm the findings that some feedstocks have a 

“negligible impact on the net carbon cycle” when utilized to produce energy and that some 

“would clearly reduce net atmospheric CO2 levels”. Commenters 0087.1 and 0052.1 asked EPA 

to expand the list of negligible impact feedstocks to include forest residues and spent pulping 

liquor. Commenter 0087.1 provided key points of several research studies as well as a life cycle 
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analyses to support this conclusion. The commenter stated that the life cycle analyses clearly 

show irrefutable GHG and renewable energy benefits of combusting spent pulping liquors for 

energy. Commenter 0052.1 also urged EPA to consider forest-product residuals and sawdust 

from milling operations as carbon neutral feedstocks. 

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0032 stated that at this early stage of development of the bioenergy 

industry, it would be unwise for the EPA to differentiate types of wood-based feedstocks and 

potentially limit their use. The commenter thought that feedstock-based exclusions will require 

additional costs and are likely to produce unintended consequences by favoring some biomass 

sources while limiting the use of others, to the detriment of the entire industry. The commenter 

gave an example that the opportunity to convert pulp mills to bio-refineries would be blocked by 

a restriction on whole tree feedstocks, even though this practice holds high promise because of 

existing biomass supplies, existing equipment, ease of modifying existing conversion methods, 

and the decline in paper markets. 

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0052.1 stated that CO2 emissions from all types of biomass are the 

result of: (i) the photosynthetic sequestration of atmospheric CO2; (ii) its transformation into 

organic carbon pools composing the forest sink; (iii) withdrawals from these pools, either by 

harvesting or natural causes; and (iv) the release of CO2 to the atmosphere upon combustion. 

Response: EPA thanks the commenter for this comment. 

Comment: Commenters 0074.1, 0023C, and 0052.1 articulated that a feedstock-based approach 

is inappropriate since general principles in accounting and science state that all feedstocks are 

part of the same carbon cycle and therefore, all biomass combustion types and situations should 

be treated equally. Commenters 0074.1 and 0023C commented that given the lack of consensus 

among commenters on feedstock issues, EPA should not apply a feedstock-based approach, and 

any attempt to differentiate feedstocks must be based on policy preferences rather than 

underlying scientific properties. Commenter 0074.1 cautioned that to differentiate the carbon 

attributes of different species of trees, parts of trees, or specific forests will produce arbitrary 

results that confuse rather than clarify the nature of the carbon cycle as well as the carbon impact 

of biomass combustion and the forestry industry as a whole. Furthermore, the commenter 

indicated that rather than using a feedstock-based approach that dictates to forest owners the 

permissible uses of their products, EPA should treat all biomass equally and allow markets to 

distribute it in an efficient manner. Commenter 0074.1 explained that the interest in a feedstockbased approach appears rooted in the irrational fear that “whole trees” will be used for energy 

production. Forest products are allocated by market forces and energy feedstocks are among the 

lowest-value products. The commenter cites that the average price per green ton of biomass is 

significantly less that the price of pulpwood or the price of saw timber and states that without a 
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significant dislocation within the forest products market, it is simply not economical to use 

whole trees for bioenergy. 

Similarly, commenter 0111.1 stated that differentiating between biomass feedstocks for BACT 

permitting could require the EPA to begin regulating feedstock sourcing, land use, and 

determining sustainable sourcing requirements. This would potentially open the door to federal 

greenhouse gas regulation of lands, which is a controversial issue, and one that has been 

traditionally relegated to the states. Additionally, asserting differences in biomass feedstocks, 

even in “broad categories” as outlined in the BACT document, would pick certain biomass 

feedstocks as more desirable than others. Biomass feedstock utilization is a decision best left to 

land owners, market forces, and local jurisdictions; selecting certain feedstocks risks distorting 

bioenergy and related forest product markets.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0079.1 stated that in this proposal the deferral will apply to biogenic 

CO2 emissions from biogenic feedstocks and is not limited to specific types of facilities. The 

commenter agrees that EPA should not limit the deferral based on the type of facility but rather 

should look at feedstocks.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0082.1 stated that requiring feedstock separation and sourcing proof is 

not practical for a permit holder because highly complex supply systems with feedstocks coming 

from many sources and undergoing intermediate processing cannot be cost-effectively tracked to 

original sources with the rigor needed to make a defensible compliance certification as required 

under Title V.

Response: EPA will consider this issue carefully in our review of the scientific and technical 

issues related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking 

to establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0086.1 supported the feedstock-based approach but only if EPA does 

not provide a categorical exemption. The commenter indicated that the carbon cycle for 

annually planted crops is rapid and does not raise the concerns identified by opponent’s biogenic 

fuels. 

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs.

Comment: Commenter 0101.1 noted that there is a potential for the biomass power projects to 

achieve even lower net emissions if the PSD program were to require consideration of the use of 
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fuels that decay quickly if not combusted, such as forest residue or waste. The commenter also 

mentioned that it is necessary to analyze the specific impacts associated with particular fuels 

along with the direct emissions to determine the net effect of a project on achieving near-term 

climate goals since the use of particular biomass fuels can partially offset those emissions. 

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0023E articulated that a rational lawful alternative to a complete 

exemption could be to include a BACT guidance document laying out credible scientifically 

sound accounting methodologies that take into account the carbon debt associated with burning 

biomass for energy. The commenter also stated that, accurate carbon accounting will show 

which biomass fuels are simply not acceptable as carbon neutral or carbon mitigating fuel 

alternatives in terms of greenhouse gas reductions. However, the commenter indicated that 

EPA’s scientific study can inform this guidance but is not needed in order to put it forward.

Response: EPA thanks the commenter for this comment.

Comment: Commenter 0144.1 stated that they utilize biomass waste made available from the 

activities of the wood products industry and other waste biomass such as chipped railroad ties. 

In Minnesota, it has been demonstrated that forest utilization for wood product harvest is 

outpaced by forest re-growth supported by good forestry practices. Biomass such as waste 

railroad ties would undergo decomposition to CO2 and methane if placed in landfills so use for 

energy applications delivers an environmentally preferred outcome. Consequently, the 

commenter encourages EPA to include waste products like railroad ties, biomass derived from 

forests and agricultural derived biomass in an immediate, blanket exclusion. The commenter also 

noted that while railroad ties can be transported a long distance before they get chipped for 

energy production and wood waste transportation can involve greenhouse gas emissions, the 

same holds true for transport of other energy sources like coal, oil and natural gas delivered to 

Minnesota, which has limited in-state energy resources.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

15.8 Whole Trees

Comment: Commenter 0104.1 stated that burning whole trees for power has been shown to lead 

to long-term increases in greenhouse gas emissions when compared to coal. The commenter 

cited several references to support concerns that biomass carbon neutrality is not justified when 

trees are harvested and combusted as fuel. The commenter also provided references which state 

that using standing trees for fuel creates a “carbon debt” of CO2 emissions because wood fuels 

release more CO2 per unit of useful energy than coal. The commenter also stated that accounting 

for use of whole trees requires consideration of the long-term carbon debt from the lost 

sequestration of harvested mature trees, the added emissions from using biomass fuels with 

inferior heating values compared to fossil fuels, and the years before the harvested tree is 

replaced by a mature tree. The commenter concluded that such a feedstock does not approach 
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carbon neutrality within 50 years and is worse than coal within the first one to three years. 

Commenter 0104.1 reported that trends in the bio-power industry are towards rapid growth and 

increased reliance on feedstocks that are clearly high carbon emitters. The commenter presented 

examples of whole-tree carbon accounting. The commenter indicated that different forests across 

the U.S. will have different growth rates when left unmanaged and different responses to being 

selectively cut.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs.

15.9 Wood Residues

Comment: Commenter 0104.1 stated that even if bio-power facilities were limited to using 

forest residues as fuel, the carbon balance is not clearly carbon neutral or beneficial over a shortterm period. The commenter cited a study of the use of forestry residues that concluded it takes 

30 years for net emissions from a utility-scale biomass facility to achieve parity with net 

emissions from electricity generation using natural gas. The commenter also cited a Finnish 

study which reported that harvesting residues for fuel has consequences for the overall forest 

carbon balance, and the commenter stated that these resources require further study. Commenter 

0104.1 also stated that EPA’s assertion that burning “dead trees” killed by mountain pine beetles 

would “clearly reduce CO2 emissions,” is unsupported since dead trees take far longer to 

decompose than logging residues.

Response: The commenter raises issues related to the temporal scale of decay versus 

combustion, as well as forest regrowth following harvest. EPA will consider these issues in our 

review of the scientific and technical issues related to accounting for biogenic CO2 emissions, as 

well as in the subsequent rulemaking to establish the treatment of these emissions in the PSD and 

Title V programs.

15.10 Future Market Demand for Other Biomass Crops

Comment: Commenter 0086.1 stated that since there is no empirical evidence that ethanol 

expansion has caused conversion of forest to agriculture in the U.S. or abroad, future market 

demand should not be considered in EPA’s analysis.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions. 

Comment: Commenter 0104.1 stated that there are examples of biomass fuels that would be 

clearly carbon beneficial, such as perennial grasses, but these feedstocks are not the direction 

industry is headed.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 
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15.11 Biological Decomposition

Comment: Commenter 0091.1 stated that biogenic CO2 generated through waste decomposition 

is “not anthropogenic” and consistent with established GHG accounting practices they should not 

be counted as contributing global warming because these emissions represent CO2 that was 

removed from the atmosphere to make the biomass that is decomposed in the landfill. The 

commenter also stated that any increase of biogenic CO2 emissions from a landfill are 

simultaneously reducing CH4 emissions from the landfill.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0091.1 stated that the difficulty in landfill gas (LFG) accounting arises 

from the fugitive portion of LFG. Quantifying fugitive emissions requires modeling LFG 

generation and estimation of the quantity of methane oxidation in landfill cover materials. The 

inaccuracy of current LFG models has been well documented as ranging from 30 to 400%. The 

commenter is concerned that this level of error is unacceptable in permitting exercises even 

though fugitive emissions would not trigger PSD, but the commenter is concerned they would be 

included in accounting once PSD was triggered for another reason.

Response: Quantification of fugitive emissions from landfills for permitting is outside the 

scope of this rulemaking. This rulemaking defers the application of the PSD and Title V 

programs to biogenic CO2 emissions for a period of three years. This deferral is intended to be a 

temporary measure to allow the Agency time to complete its work and determine what, if any, 

the treatment of biogenic CO2 emissions should be in the PSD and Title V programs.

Comment: Commenter 0117.1 believes that the calculations used in EPA’s recent biogenic 

emissions estimation methods report for landfills, ethanol production, and wastewater treatment 

plants could over-estimate POTW emissions. The commenter expressed concern about the 

impact of overestimation while EPA considers the deferral of biogenic CO2 emissions. Although 

this report is one of several methodologies yielding widely different emissions estimates for 

POTWs, the commenter is concerned that it is the only EPA-sanctioned guidance on the topic, 

and many regulatory authorities may defer to this document in lieu of other sources of 

information.

Response: EPA notes that this rule does not make or infer any policy determination on the part 

of EPA as to whether, or what part of, emissions from any sources may be determined “fugitive”

emissions for the purposes of accounting and applicability under air permitting requirements. 

Such determinations are not within the scope of this rule and are part of the case-by-case 

application and review process established under the regulations covering these permitting 

requirements. The draft methodology report the commenter cites is outside the scope of this 

rulemaking. EPA does note this report is out for review now EPA looks forward to receiving 

feedback from stakeholders, especially with specific data to support or refute the accounting 

methodology under consideration. 
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15.12 Biogas Combustion

Comment: Commenter 0059.1 stated that landfill gas recovery and utilization provide valuable 

opportunities for GHG reductions. Landfill gas methane can be collected in high efficiency gas 

collection systems, and then either destroyed by combusting the collected gas in flares, or used 

as fuel in engines or furnaces. Currently, there are 518 operational landfill gas to energy projects 

in the U.S., which create 1,615 megawatts (MW) of electricity and 285 million metric standard 

cubic feet per day (MMSCFD) of renewable fuel as reported by EPA’s LMOP. However, there 

are many more landfills in the U.S. that have the potential to capture and utilize landfill gas. EPA 

identifies 520 candidate landfills that have the potential for landfill gas to energy projects. The 

commenter is concerned that regulating the biogenic emissions from landfills has the potential to 

derail the excellent work done by EPA’s LMOP program, by increasing the cost of compliance 

for what is a renewable energy.

Commenter 0059.1 stated further that while EPA is examining BACT for different sources, they 

should consider the total net emissions of these sources on a lifecycle basis. LFG recovery 

projects reduce GHG emissions, and this should be a factor when determining not only threshold 

eligibility, but presumptive BACT. This valuable source of energy has helped states and 

communities meet their GHG reduction goals and would be put at a significant disadvantage 

were EPA to regulate biogenic emissions.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0023K suggested that EPA recognize that biogenic emissions from 

waste water treatment utilities result from a different process than emissions from harvested 

biomass and some other biological sources. The commenter explained that wastewater utilities 

treat waste to protect the environment and public health and are required to meet the standards of 

the Clean Water Act. Human waste is produced every day and produces greenhouse gases as it 

breaks down whether or not it is treated by utilities. The biogas produced from the treatment

process consists mostly of methane which is converted to CO2 when combusted. Using biogas to 

generate and recover heat and to generate electricity reduces and sometimes even eliminates the 

treatment process’s reliance on fossil fuels while lowering GHG emitted from treating waste 

through the use of biogas. The commenter mentioned that some utilities are using energy 

recovery methods for bio-solids as well as taking advantage of the fact that bio-solids contain 10 

times the energy needed to treat them. The commenter recommends that wastewater utilities 

should be encouraged to implement and further develop their heat and energy recovery program 

using biogas and biosolids, and emissions from these activities should not be counted in 

permitting applicability determinations under the Act.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

Comment: Commenter 0099.1 stated that biogas is a green renewable energy resource that 

should continue to be promoted as an environmentally-friendly alternative to fossil fuel; digester 
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and landfill gas are renewable fuels that are continuously available; regulation of biogenic 

emissions from combustion of biogas only serves as a disincentive to renewable energy 

production and use.

Response: EPA will consider these issues in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

15.13 Biogenic Fraction of MSW

Comment: Commenter 0091.1 stated that since land filling is a significant sink of carbon, the 

quantity of carbon sequestered should be considered a credit under GHG regulations to be 

consistent with previous statements by EPA on this subject and consistent with other U.S. and 

international GHG accounting conventions. The commenter argued that at a minimum, 

sequestration of other biogenic carbon should be allowed as part of the net calculations that 

landfills use to determine their contribution of GHG to the environment.

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions.

Comment: Commenter 0082.1 stated that EPA’s Mandatory GHG reporting rule’s methodology 

to calculate CH4 emissions from landfills can grossly overestimate these emissions, and the 

commenter made the following suggestions: 

1. Allow landfills that have gas collection systems to calculate the CH4 emissions by using 

the collected gas information. This approach would provide the total landfill gas 

collected, the percent CH4 contained in the collected gas, and the portion of the gas 

treated. Using this information, the amount of CH4 and CO2 emitted to the atmosphere 

can be easily calculated.

2. Allow the use of both the default DOC factor and tested DOC values for the same year.

3. The definition of inert material §98.460 (c)(2)(i) “Coal combustion residue (e.g. fly ash)”, 

should be expanded to include other boiler ashes, e.g. from wood fired boilers when 

using equations HH-1 or TT-1.

4. The definition of inert material in §98.460 (c)(2)(xii) “Other waste that has a volatile 

solids concentration of 0.5 weight percent (on a dry basis) or less”, should be modified to 

show a threshold of 10% instead of 0.5%.

Response: EPA thanks the commenter for the suggestions and notes the methodologies for 

EPA’s GHG Reporting Program are outside the scope of this rulemaking. 

Comment: Commenter 0059.1 stated that WTE facilities provide an essential service to the 

local governments that rely on them to manage their solid waste. There are 87 WTE plants 

operating in 25 states managing about 7 percent of America’s solid waste, or about 90,000 tons 

each day. The nation’s WTE plants have a base load electric generation capacity of 

approximately 2,700 megawatts to meet the power needs of more than two million homes while 

serving the waste disposal needs of more than 36 million people. A majority of the nation’s WTE 

facilities are owned by local governments that have invested in this critical municipal 

infrastructure to achieve long-term solid waste management solutions. EPA has requested 
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comments on the comparison between biomass sources and fossil fuels. A study conducted in 

2005 by the commenter’s Applied Research Foundation compared the air emissions of WTE to 

those of coal, oil and natural gas showing that on the whole, WTE significantly reduces pollutant 

emissions (these emissions estimates are based upon national averages – specific regions of the 

country may differ). In addition to this study, in 2003 EPA referred to WTE as “a clean reliable, 

renewable source of energy that produce(s) 2800 megawatts of electricity with less 

environmental impact than almost any other source of energy.”

Response: EPA thanks the commenter for the information. 

Comment: Commenter 0059.1 stated that EPA must consider lifecycle analyses when 

developing BACT for sources with significant biogenic emissions. The commenter suggested 

that while EPA is examining BACT for different sources, they consider the total net emissions of 

these sources on a lifecycle basis. WTE recovery projects reduce GHG emissions and this should 

be a factor when determining not only threshold eligibility, but presumptive BACT. The direct 

emissions from WTE facilities are more than offset by the overall GHG reductions that WTE 

provides. 

Response: EPA will consider this issue in our review of the scientific and technical issues 

related to accounting for biogenic CO2 emissions, as well as in the subsequent rulemaking to 

establish the treatment of these emissions in the PSD and Title V programs. 

15.14 Open-loop Biomass

Comment: Commenter 0023F stated that the carbon benefits of open-loop biomass enjoy 

widespread support even from those who claim an error in GHG accounting principles. The 

commenter cited several studies supporting the use of sustainably harvested wood and forest 

residues as well as organically based municipal and industrial wastes as fuels when compared to 

fossil fuels. The science behind the use of open-loop biomass is compelling and beyond dispute.

Response: EPA thanks the commenter for the comment.
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16.0 Forest Economics and Sustainability

EPA appreciates the comments received on this topic. Many of the issues raised in these

comments are beyond the scope of this action and will be considered in EPA’s subsequent work 

on biogenic CO2 emissions from stationary sources, including the Agency’s detailed examination 

of the science and technical issue and any subsequent rulemakings. 

16.1 Forest Biomass Use is Sustainable

Comment: Commenter 0032 stated that forest biomass is the most promising energy feedstock 

in Georgia due to abundant forestland and strong markets. Commenter 0032 recounted a brief 

history of southern forests reflecting that rising demand for forest biomass was sustainable and 

provided data showing growth in supply (i.e., inventory of forests) outpaced demand (timber 

utilization) during a recent 54 year period of rapid market expansion.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand beyond the scope of this action.

Comment: Commenter 0111.1 stated that over the past century, forest stock has increased by 

nearly 50%, a growth running parallel to national economic expansion and greater resource use. 

Forest management decisions on growth and harvest are often projected decades in advance of 

potential uses, thereby sequestering future carbon emissions in the process. Forest tracts must be 

given the flexibility to practice sustainable forestry as deemed appropriate by their jurisdiction.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about forest stocks beyond the scope of this action.

Comment: Commenter 0046 stated that using the commenter’s logging slash for energy will 

mean that they will not need to burn slash piles, and will reduce wildfire risk. Using the logging 

slash for energy will provide renewable energy, more rural jobs and healthier, less fire-prone 

forests.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass feedstocks and renewable energy policy beyond the scope of this action.

Comment: Commenter 0049.1 stated increasing harvests has two primary effects on habitat and 

biodiversity. The commenter explained that removing wood results in a more open residual 

stand, new species will inhabit the stands and other species will be eliminated, important dead 

wood will be eliminated, which results in lack of habitat and species, and has negative impacts 

on long-term soil productivity.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about impacts on biodiversity beyond the scope of this action.

Comment: Commenters 0146 and 0013.1stated that use of forest biomass as a biogenic fuel 

stock is sustainable and cited historical data to show that as the demand for forest products 

increased, the volume of trees also grew at both the national and regional scale. The commenter 
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quotes from a study showing U.S. forest acreage has remained stable over the past 100 years, and 

forest owners have consistently planted more than they harvested since the 1940s during a period 

of unprecedented demand for forest products. However, the commenter also quoted a study from 

the University of Georgia and North Carolina State University showing that private U.S forests 

are not as productive as they could be due to depressed market prices and reduced manufacturing 

capacity. This study also demonstrated that increased markets for biomass energy can lead to 

increased sustainable yields from private forestlands and stimulate production increases ranging 

from 75% to 150% over the next 25 years. 

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand and economic incentives beyond the scope of this action.

Comment: Commenter 0146 further suggested that the demand for biomass energy should be 

projected realistically, because every announced project will not be constructed and cited a 

market-research service’s methodology for assessing viability of proposed projects. For 

example, the service found 446 wood-consuming projects in development, with potential for 

additional wood use of 123.7 million tons/year by 2021, but estimated that only 68.5 million 

tons/year are likely to be online by 2021.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand beyond the scope of this action.

Comment: Commenter 0075.1 supported deferral and stated that emerging bioenergy markets 

could benefit wildlife habitat in general, by providing income to private landowners, which 

encourages them to keep their lands forested or in other permanent vegetative cover rather than 

to convert them to other uses such as tillage agriculture or residential developments.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand and economic incentives beyond the scope of this action.

Comment: One commenter 0023B suggested EPA develop sustainability criteria for eligible 

biomass types and thus allow those biomass sources determined to be sustainable to be exempted 

from the Tailoring Rule.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass sustainability beyond the scope of this action.

16.2 Forest Economics and Markets

Comment: Commenters 0032 and 0074.1 stated that the market forces of supply and demand 

will lead to increased forest stocks if the value of forests increase, because economic returns on 

wood production provide important incentives for private forest stewardship, and without these 

incentives, many working forests would be converted to more profitable non-forest uses. 

Commenter 0074.1 believes that new markets for biogenic fuels can enhance the economic 

sustainability of working forests and contribute to maintaining or increasing the extent of forests 

on private lands, but Commenter 0074.1 disagreed with the “notion” that restrictions on using 

forests as a biogenic fuel source could help preserve forests, because if the government restricts 
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the use of a renewable resource, stocks of that resource will naturally fall; this commenter 

provides a link to a supporting economic study. 

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand and markets beyond the scope of this action.

Comment: Commenter 0072.1 stated that biomass currently provides over 50 percent of 

America’s renewable energy according to the EIA, and noted that biomass from sustainably 

managed forests offers a green alternative to fossil fuel combustion. The commenter indicated 

that forest products manufacturers are leaders in the practice of sustainable forest management. 

The commenter stated that biogenic combustion promotes forest growth and management by 

encouraging land owners to maintain their forests rather than using land in ways without carbon 

storing benefits, and regulating biomass would deter land owners from maintaining forests.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass sustainability beyond the scope of this action.

Comment: Commenter 0146 emphasized the role of emerging bioenergy markets in sustaining

forest conservation and suggested that the biomass fuel markets could potentially replace other 

declining markets and add economic value to private forest ownership. The commenter also 

thought that the greatest threat to deforestation is the conversion of private forests (57% of all 

U.S. forests) to more profitable, non-forest uses. The commenter stated that the markets for 

forest products, tax liability and the cost of regulation are key considerations when forest owners 

evaluate alternative uses for their forest land. 

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand and markets beyond the scope of this action.

Comment: One commenter (0060) stated that without a deferral, the rule would add yet another 

burden for companies that are trying to become independent from the need of foreign oils. 

Instead of taking some of the air permitting off this project, the rule would require another 

expensive analysis to be conducted.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about fuel diversity beyond the scope of this action.

Comment: Commenter 0023C linked historic trends of increasing demand for forest products 

with trends of stable or increasing forest acreage at the national scale, and the commenter cited 

data for a period of high demand for forest products that saw a seven fold increase in U.S. 

housing starts and a 25 fold increase in pulpwood consumption while total U.S. forest acreage 

remained constant. The commenter stated that during the second half of the 20th century the total 

growing stocks increased by 50%. Given that forests sequester an estimated 800 million tons of 

carbon annually and more than 80% of the carbon sequestered by all land uses, the commenter 

argues that new markets do not reduce the forests, but rather increase forest stocks. The 

commenter stated that private forests and markets need each other to survive, but that market 

losses put economic pressure on private forests to convert to more profitable uses with lower 
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sequestration capacities. The commenter stated that EPA policy must reflect market forces in 

order to fully realize the sequestration capacity of private forests.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand and forest stocks beyond the scope of this action.

Comment: Commenter 0137.1 stated that there is high degree of probability that emerging 

markets for wood pellets will demand large tracts of standing trees be used as a primary 

feedstock in the Southeast region. The commenter reported a case of increasing demand for 

wood pellets in the Southeast, which has exhausted the supply of residual wood. The commenter 

also cited a study and provided two figures indicating that the wood pellet industry is growing, 

mainly from the exports to other regions and countries. The commenter argued that since the EU 

strives to meet its renewable targets by 2020, wood pellets will be a key to achieving these 

targets, especially in the heating sector. The commenter provided a figure, showing the 

significant role the American South currently plays in wood pellet production and is projected to 

play in the near future. Several examples of plans for increased wood pellet production are also 

given.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand and renewable energy beyond the scope of this action.

Comment: Commenter 0057.1 stated that policies that encourage the use of forest biomass 

create positive economic and climate benefits. By not regulating biomass emissions in the same 

way as fossil fuel emissions, EPA creates additional markets for biomass that is currently underutilized. The economic benefits from this are obvious; supporting and creating new jobs in rural 

communities throughout the United States. By supporting and creating additional value, biomass 

markets will add to the value of forestland in the United States. This creates an incentive for 

investment in forestland to grow, harvest, and replant trees as opposed to investment in other 

land uses that do not provide the benefits of carbon storage that come from sustainably managed 

forests. Additionally, increased use of biomass energy in all of its forms can be utilized in lieu of 

fossil fuels. This substitution effect can contribute to significant atmospheric CO2 reductions 

when compared to fossil fuels.

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass supply and demand and economic incentives beyond the scope of this action.

Comment: Commenter 0065.1 stated that by excluding CO2 emissions from biomass 

combustion from the PSD and Title V applicability requirements, the EPA may incentivize 

increased logging of whole trees and conversion from natural forests into plantations or 

cultivated systems which could have serious effects on the net atmospheric CO2 levels. Natural 

forests play a significant role in mitigating already rising levels of atmospheric CO2. Our forests 

must be protected from anthropogenic activities that would reduce carbon stocks of our forested 

lands. 

Response: EPA thanks the commenter for the comment and considers the commenter’s views 

about biomass economic incentives and impacts beyond the scope of this action.
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17.0 Environmental Justice

Comment: Multiple commenters (0015.1, 0030, 0110, 0143.1, 0119.1, 0132.1, 0166 0182, and 

0351) cited concerns regarding environmental justice issues related to communities surrounding 

biomass facilities. Commenters 0015.1, 0030, 0143.1 stated that an additional concern is the 

trend to construct large biomass plants in low income communities of color, where they 

contribute further to the health burden already suffered as a result of disproportionate exposure to 

toxins. Similarly, commenter 0166 states that biofuel production is especially impacting 

disenfranchised communities because the facilities receive federal stimulus dollars to develop 

projects in disenfranchised communities.

Commenter 0110 stated that biomass-to-energy proposals are already creating de facto sacrifice

zones. The commenter stated that in North Carolina, poor communities of color are being 

targeted by biomass burning facilities and provided two examples supporting this statement.

Multiple commenters (0119.1, 0132.1, and 0182) noted that Southern rural and minority 

communities have suffered from and are particularly threatened by the impact of the extractive 

timber industry both in terms of quality of life and economics. Commenter 0119.1 contended 

that assisting in the creation of another extractive forest use would not improve the economic 

situation of Southern communities.

Commenter 0119.1 also stated that encouraging development of bioenergy facilities could 

increase emission of most air pollutants and that the negative environmental justice implications 

of granting special treatment of biomass should be considered. Commenters 0119.1 and 0132.1 

stated that while the government struggles to make healthcare more available to everyone, it is 

exacerbating the causes of disease among those most likely to lack access to adequate healthcare.

Commenters 0132.1 and 0351 noted that rural and minority communities are particularly 

threatened by the negative environmental effects of biomass and waste combustion. Commenter 

0351 is especially concerned about the climate change effects and environmental justice 

concerns of a particular municipal waste combustion facility in Hartford, CT.

Response: This rule is deferring the application of the PSD and Title V programs to biogenic 

CO2 emissions for a period of three years. During this time EPA will conduct a detailed 

examination of the science and technical issues associated with biogenic CO2 and based on that 

undertake a subsequent rulemaking determining how these emissions should be treated in those 

programs. Specific projects combusting biomass are beyond on the scope of this rulemaking and 

will be dealt with on a case by case basis as they are developed as well as through other 

applicable requirements, including any related to environmental justice. 

Comment: Commenters 0048.1 and 0166 stated that because federal dollars are being used, 

EPA should require an Environmental Impact Statement (EIS) for each facility, that takes into 

consideration the potential environmental justice impacts and public health impacts (sensitive 

communities such as the elderly, poor, children, immune-compromised) as well as truly 

renewable and sustainable alternatives.

Response: This rule is deferring the application of the PSD and Title V programs to biogenic 

CO2 emissions. During this time EPA will conduct a detailed examination of the science and 
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technical issues associated with biogenic CO2 and based on that undertake a subsequent 

rulemaking how these emissions should be treated in those programs. EPA thanks the 

commenter for the comment and considers the commenter’s views about EIS or other programs 

that may provide incentives for use of renewable energy sources beyond the scope of this 

rulemaking.
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18.0 Miscellaneous

18.1 Commenters Referencing Other Commenters

Comment: Multiple commenters supported or endorsed comments from other comments, as 

follows:

Commenter 0081 supported the comments made by commenters 0071 and 0074.1. Commenter 

0120.1 endorsed comments from 0074.1.

Commenters 0083.1 and 0123.1 endorsed the positions taken by commenter 0095.1.

Commenter 0136.1 supported and incorporated by reference the comments submitted by 

commenter 0140.1.

Commenter 0137.1 concurred with commenter 0350.1.

Commenters 0052.1, 0082.1, 0085 supported and incorporated (0052.1) comments submitted by 

commenter 0087.1. Commenter 0082.1 reiterated comments from 0087.1 that the clear science 

and near-universal public policy supporting the carbon neutrality of biomass, the argument that 

EPA has clear legal authority to distinguish biogenic CO2 emissions from other sources, the 

carbon cycle should be measured on a national scale, and the most appropriate treatment of 

biomass emissions is a categorical exclusion.

Commenter 0082.1 also supported arguments submitted by commenter 0078 that that the deferral 

should not expire before the final biomass rulemaking is complete, that national biogenic 

emissions are a net sink and therefore even better than de minimis and not a contributor to global 

atmospheric carbon, that the deferral should apply beyond PSD and Title V, and that decisions 

approved during the deferral period should be honored after the deferral period ends. 

Response: We acknowledge these commenters collective support of other commenters. The 

comments reiterated by commenter 0082.1 are addressed elsewhere in this document along with 

the referenced comments (0087.1 and 0078).

18.2 Commenters Incorporating Prior Comments on Other Actions

Comment: Commenters 0023F, 0052.1, and 0142.1 incorporated their previous comments in 

response to EPA’s CFI. Commenter 0142.1 included a list of scientific studies (See EPA-HQOAR-2011-0142.1).

Commenter 0023C noted that they have provided extensive comments, outlining legal and policy 

reasons for recognizing forest as a carbon beneficial source of energy, which is all part of the 

public record.

Commenter 0115.1 cited Docket Number EPA-HQ-OAR-2010-0560 as evidence that 

combustion of feedstocks has already been proven to not be carbon neutral and instead, biomass 

fuels have adverse effects when combusted for energy production, particularly in the near term 

timeframe.
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Response: We acknowledge these commenters reiterating their previous comments.

18.3 Administrative Requirements

Comment: Commenter 0087.1 agreed that the proposal does not relate to health standards and 

does not trigger Executive Order 13045. Similarly, the commenter agreed the rulemaking does 

not implicate Executive Order 12898 (concerning environmental justice), and stated that the 

proposal is consistent with Executive Order 13563, which directs agencies to use the leastburdensome tools to achieve regulatory ends and to review existing rules to determine whether 

they are excessively burdensome and to revise them where appropriate.

Response: We acknowledge support of our determinations regarding various Executive Orders. 

18.4 Other

Comment: Commenter 0082.1 suggested that EPA consider expanding the scope of the deferral 

and longer-term rulemaking plans to cover other GHG regulations the Agency may undertake, 

such as under the NSPS for the utility and refinery sectors.

Response: EPA appreciates the views of the commenter but notes that regulation of CO2, 

including from biogenic sources, under the CAA Section 111 NSPS program is beyond the scope 

of this action. 

As additional information becomes available to the Agency on the impacts of biogenic CO2, we 

will consider the implications of biogenic CO2 in the context of other CAA programs as 

appropriate. 

Comment: Commenter 0049.1 supported EPA’s authority to enforce CAA standards to reduce 

carbon pollution that harms humans and the environment. Commenter 0023E believed EPA has 

clear authority under the CAA to regulate and reduce greenhouse gas emissions from stationary 

sources, including the many billions of tons of CO2 that are produced each year by the energy 

sector. Commenter 0023E stated EPA must use that authority now to start effectively reducing 

total CO2 emitted because a portion of every ton of CO2 emitted today persists in the atmosphere 

for 100 years.

Commenter 0350.1 strongly supported EPA in its lawful exercise of its clear authority under the 

CAA to regulate stationary sources of GHG emissions, including CO2. The commenter noted 

that actions to reduce overall CO2 emissions over the near term (measured in years rather than 

decades) are essential to avoid climate change damage. Given the evidence of climate change 

(2010 was identified as one of warmest years on record, summer sea ice is at a low, ice sheet 

runoff is in excess of estimates, and extreme weather events), and the failure of comprehensive 

climate legislation in Congress, EPA’s CAA authority remains our first and best line of defense 

against these changes.

Response: We agree with the commenter that EPA has clear authority to regulate stationary 

sources of GHG emission under the CAA and note that this issue has been addressed in previous 

GHG rulemakings. See, e.g., Final Endangerment and Cause or Contribute Findings for 

Greenhouse Gases under Section 202(a) of the CAA, 74 FR 66496, 66500
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(Dec. 15, 2009)

Comment: Commenter 0077.1 recognized that the biological systems involved and the carbon 

lifecycle accounting is scientifically and technically complicated. The commenter stated that it is 

imperative to understand the science so that EPA can develop a predictable and science-based 

regulatory structure under which the regulated community can pursue investments in 

environmental improvements in their facilities.

Response: EPA thanks the commenter for their comment. During the three year deferral period 

EPA is conducting a detailed examination of the science and technical issues associated with 

accounting for biogenic CO2 from stationary sources. 

Comment: One commenter (0112) expressed concerns over the proposed wood burning power 

plant, located in Russell Massachusetts by Biomass LLC. The commenter is concerned about the 

negative impacts to the Westfield River in Westfield, Massachusetts, and its surrounding 

environment. The commenter brought up the negative environmental effects of the plant 

including water flow. Also, the commenter noted no reference could be found in the Russell 

Biomass engineering study on the Hubbard Brook Ecosystem Study concerning the watershed 

effects from clear cutting and removing timber in a watershed. Lastly, no reference from the 

USGS Study of the Rivers Aquifer Information was included in the Russell Biomass engineering 

study either. 

Response: We acknowledge this comment, but note that comments pertaining to specific 

facilities are outside the scope of this rulemaking.

Comment: Commenter 0130.1 provided an anecdote that highlighted their concern over the 

development of biomass facilities by organizations with no prior experience in assessing the 

impacts of a biomass incinerator venture, i.e., only 1 of 22 companies involved in the venture 

have any waste management experience, and cited a report by a Charlotte, North Carolina area 

Waste Management Advisory Board (see EPA-HQ-OAR-2011-0083-0130.1).

Response: We acknowledge this comment, but note that it is outside the scope of this 

rulemaking. 

Comment: Commenter 0132.1 stated that not only does the federal stimulus program put our 

communities at risk, it may create a loophole in the National Environmental Policy Act, because 

the US Treasury Department maintains that, “A Section 1603 payment with respect to specified 

energy property does not make the property subject to the requirements of NEPA and similar 

laws[,]” and the commenter insists the public needs the EIS process as a counterbalance to the 

rush to approve and permit increases in pollution from biomass projects.

Response: We acknowledge this comment, but note that it is outside the scope of this 

rulemaking.

Comment: Commenter 0092 submitted several electronic mail letters, figures, and journal 

articles regarding alternative methods of carbon sequestration (see EPA-HQ-OAR-2011-0083-

0092.pdf; EPA-HQ-OAR-2011-0083-0092.1.pdf; EPA-HQ-OAR-2011-0083-0092.2.pdf; EPA-
18.0 Miscellaneous

183

HQ-OAR-2011-0083-0092.3.pdf; EPA-HQ-OAR-2011-0083-0092.4.pdf; EPA-HQ-OAR-2011-

0083-0092.5.pdf).

Response: We thank the commenter for submitting additional information regarding alternative 

methods of carbon sequestration. We will review these during the three-year detailed 

examination of the science and technical issues associated with accounting for biogenic CO2

emissions from stationary sources.
Appendix A

A-1

Appendix A

General Public Submissions

This appendix presents a list of public submissions, or “comments,” received by the Air Docket 

on the proposed Deferral Rule. The first column identifies each comment by its unique 

Document ID number in the docket. 

In the second column, we have classified the comments by “letter type” to reflect certain 

recurring characteristics. The letter type for each submission includes the following 

classifications:

• General Support – comments expressing general support for the Deferral Rule

• General Opposition – comments expressing general opposition to the Deferral Rule

• Form Letter # – comments submitted by more than one Individual or organization 

including mass comment campaigns; each such form letter is assigned a number 

• Other Comment – contains other comments not included in the “General Support,”

“General Opposition,” or “Form Letter #” comments

This classification system was used to identify substantially-similar comments and themes, 

although many Individual comments could have been assigned more than one of the “letter type”

classifications. 

The third column presents the organization that submitted each comment. In instances where an 

Individual has signed his or her name to a comment letter but no organization is indicated, the 

“organization” is listed as “Individual.” Examples of some of the Form Letters received and 

listed in Appendix A are included in Appendix B.

Appendix A. List of General Public Submissions on the Proposed Deferral Rule3

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0012 Other comment Individual

0013.1 Form letter #0146 The Miller De Wulf Corporation

0016 General opposition Individual

0017 General opposition Individual

0018 General opposition Individual

0019 General opposition Individual

0020 General opposition Individual

0021 General opposition Individual

 

3 This list reflects submissions that were not excerpted in the main body of this document because they fit within the 

context of other significant comments.
Appendix A

A-2

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0024.1 Form letter #0146 Thermal Energy Development Partnership, LP

0025 General opposition Individual

0026 General opposition PT AirWatchers

0027 General opposition WACE

0028 General opposition Individual

0031 General opposition Wiregrass Activists for Clean Energy

0034 General opposition Neighborhood Environment Watch

0035 General opposition Individual

0036 General opposition PT AirWatchers

0040 General opposition Individual

0041 General opposition Arise for Social Justice

0061 General opposition Individual

0068 General opposition Individual

0098 Form letter -

Moratorium Individual

0113 Other Individual

0146 Form letter #0146 Resource Management Service, LLC

Mass comment campaign (32)

0147 Form letter #0147 Mass comment campaign: organization unknown (129)

0148 Form letter #0148 Mass comment campaign: organization unknown (33)

0149 Form letter #0149 Mass comment campaign: NRDC

(10,262)

0151 Form letter #0149 Individual

0152 General opposition Individual

0153 General opposition Individual

0154 Form letter -

Moratorium Individual

0155 Form letter #0149 Individual

0156 General opposition Individual

0157 Form letter #0146 Individual

0158 Form letter #0149 Individual

0159 Form letter #0149 Individual

0160 Form letter #0149 Individual
Appendix A

A-3

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0161 Form letter #0149 Individual

0162 Form letter #0149 Individual

0163 Form letter #0149 Individual

0164 Form letter #0149 Individual

0165 Form letter #0149 Individual

0166 Form letter -

Moratorium Individual

0167 General opposition Individual

0168 Form letter #0149 Individual

0169 Form letter #0149 Individual

0170 Form letter #0147 Individual

0171 General opposition Individual

0172 General opposition Individual

0173 Form letter #0147 Individual

0174 Form letter #0147 Individual

0175 General opposition Individual

0176 General opposition Individual

0177 General opposition Protect Our Woods

0178 General opposition Individual

0179 Form letter #0147 Individual

0180 Form letter #0147 Individual

0181 General opposition Individual

0183 Form letter -

Moratorium Individual

0184 Form letter #0147 Individual

0185 General opposition Individual

0186 Form letter -

Moratorium Individual

0187 General opposition Individual

0188 General opposition Individual

0189 Form letter #0147 Individual

0190 General opposition Individual

0191 Form letter #0149 Individual
Appendix A

A-4

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0192 Form letter -

Biofuelwatch Individual

0193 Form letter #0147 Concerned Citizens of Perryville

0194 Form letter -

Moratorium Individual

0195 Form letter -

Moratorium Individual

0196 Form letter #0147 Individual

0197 Form letter #0147 Individual

0198 General opposition Individual

0199 Form letter #0149 Individual

0200 Form letter #0147 Individual

0201 Form letter -

Biofuelwatch Individual

0202 Form letter #0149 Individual

0203 Form letter #0149 Individual

0204 Form letter #0149 Individual

0205 Form letter #0148 Individual

0206 General opposition Individual

0207 Form letter #0149 Individual

0208 Form letter #0149 Individual

0209 Form letter -

Moratorium Individual

0210 Form letter #0149 Individual

0211 Form letter #0149 Individual

0212 General opposition Individual

0213 Form letter #0149 Individual

0214 Form letter #0149 Individual

0215 Form letter #0149 Individual

0217 Form letter #0149 Individual

0218 Form letter #0149 Individual

0219 Form letter #0149 Individual

0220 Form letter #0149 Individual

0221 Form letter #0149 Individual
Appendix A

A-5

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0222 Form letter #0149 Individual

0223 Form letter #0149 Individual

0224 Form letter #0149 Individual

0225 Form letter #0149 Individual

0226 Form letter #0149 Individual

0227 Form letter #0149 Individual

0228 Form letter #0149 Individual

0229 Form letter #0149 Individual

0230 General opposition Individual

0231 Form letter #0149 Individual

0232 Form letter #0149 Individual

0233 Form letter #0149 Individual

0234 Form letter #0149 Individual

0235 General opposition Individual

0236 Form letter #0149 Individual

0237 Form letter #0149 Individual

0238 Form letter #0149 Individual

0239 Form letter #0149 Individual

0240 General opposition Individual

0241 Form letter #0149 Individual

0242 Form letter #0149 Individual

0243 Form letter #0149 Individual

0244 Form letter #0149 Individual

0245 Form letter #0149 Individual

0246 Form letter #0149 Individual

0247 Other comment Individual

0248 Form letter #0149 Individual

0249 Form letter #0149 Individual

0250 General opposition Individual

0251 Form letter #0149 Individual

0252 Form letter #0149 Individual

0253 General opposition Individual
Appendix A

A-6

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0254 Form letter -

Biofuelwatch Individual

0255 Form letter #0147 Individual

0256 Form letter #0147 Individual

0257 Form letter -

Biofuelwatch Individual

0258 General opposition Individual

0259 General opposition Individual

0260 Form letter -

Biofuelwatch Individual

0261 General opposition Individual

0262 Form letter #0147 Individual

0263 General opposition Individual

0264 General opposition Individual

0265 General opposition Olympic Forest Coalition

0266 General opposition Individual

0267 Form letter #0147 Individual

0268 General opposition Individual

0270 Form letter -

Biofuelwatch Individual

0271 General opposition Biomass Accountability Project

0272 General opposition Individual

0273 Form letter -

Moratorium Individual

0274 General oppostion Individual

0276 General opposition Individual

0277 Form letter -

Moratorium Individual

0278 Form letter #0147 Individual

0279 General opposition Individual

0280 Form letter #0147 Individual

0281 Form letter #0149 Individual

0282 General opposition Individual

0283 Form letter #0147 Individual
Appendix A

A-7

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0284 Form letter #0147 Individual

0285 Form letter #0149 Individual

0286 Form letter #0149 Individual

0287 Form letter #0149 Individual

0288 Form letter #0149 Individual

0289 Form letter #0149 Individual

0290 General opposition Individual

0291 General opposition Individual

0292 Form letter #0149 Individual

0293 Form letter #0149 Individual

0294 Form letter #0149 Individual

0295 Form letter #0149 Individual

0296 Form letter #0149 Individual

0297 Form letter #0149 Individual

0298 Form letter #0149 Individual

0299 Form letter #0149 Individual

0300 Form letter #0149 Individual

0301 Form letter #0149 Individual

0302 Form letter #0149 Individual

0303 Other comment Individual

0304 Form letter #0149 Individual

0305 General opposition Individual

0306 Form letter #0149 Individual

0307 Form letter #0149 Individual

0308 Form letter #0147 Individual

0309 General opposition Individual

0310 Form letter #0147 Individual

0311 General opposition Individual

0312 Form letter #0149 Individual

0313 General opposition Individual

0314 General opposition Individual

0315 Form letter #0149 Individual
Appendix A

A-8

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0316 General opposition Individual

0317 Form letter #0149 VFR/The Enviro Show

0318 Form letter #0147 Individual

0320 Form letter #0149 Individual

0321 General opposition Individual

0322 General opposition Individual

0323 Form letter -

Moratorium Individual

0324 Other comment Individual

0325 Form letter #0149 Individual

0326 Form letter -

Moratorium Individual

0327 Form letter #0147 Individual

0328 Form letter #0149 Individual

0329 Form letter #0149 Individual

0330 Form letter #0147 Individual

0331 Other comment Individual

0333 Form letter -

Moratorium Horry Environmental Action Team (HEAT)

0334 Form letter #0149 Individual

0335 Other comment Individual

0336 Form letter #0149 Individual

0337 Form letter #0149 Individual

0338 Form letter -

Moratorium Individual

0339 Form letter #0149 Individual

0340 Form letter -

Moratorium World Temperate Rainforest Network

0341 Form letter -

Moratorium Protect All Children’s Environment

0342 Form letter #0149 Individual

0343 Form letter #0149 Individual

0344 Form letter #0147 Individual

0345 General opposition Individual
Appendix A

A-9

Docket No.

EPA-HQ-OAR2011-0083Letter Type Organization

0346 Form letter -

Biofuelwatch Individual

0347 Form letter -

Moratorium Individual

0348 General opposition Individual

0349 General opposition Individual

0352 General opposition American Academy of Family Practice

0353 Other NC Health of the Public Council

0356 Form letter -

Moratorium Individual
Appendix B

B-1

Appendix B

Examples of Form Letters
Fwd: [pt-nobiomass] FW: docket ID No. EPA-HQ-OAR-2011- 0083-Do NOT 

defer biomass rulings fo 3 years!

chris marrs to: GHGBiogenic 05/03/2011 09:35 AM

---------- Forwarded message ----------

From: Duff Badgley <duff@nobiomassburn.org>

Date: Sun, May 1, 2011 at 11:39 AM

Subject: [pt-nobiomass] FW: docket ID No. EPA-HQ-OAR-2011- 0083-Do NOT defer biomass 

rulings fo 3 years!

To: Forests listserve-newest <forests-biomass@googlegroups.com>, PT listserve <

pt-nobiomass@lists.riseup.net>, Simpson listserve <c4hf@yahoogroups.com>, NO ADAGE 

Yahoo Group <noadage@yahoogroups.com>

--"Woody biomass energy" discussion and action list. Take action!--

Special announcement: PLEASE DONATE! We need to raise $15,000 for current legal bills! 

Every bit helps tremendously!

----

Please forward this email, or another of your own, back to ghgbiogenic@epa.gov referencing 

docket ID No. EPA-HQ-OAR-2011- 0083 in subject line. We have only until May 5, 2011 to 

submit comments. This information assembled by Blue Ridge Environmental Defense League 

and forwarded by Bill Blackley, MD of North Carolina. Thanks!--Duff

From: duff@nobiomassburn.org

To: ghgbiogenic@epa.gov

Subject: docket ID No. EPA-HQ-OAR-2011- 0083

Date: Sun, 1 May 2011 11:31:40 -0700

The EPA must not defer biomass rulings for three years re docket ID No. 

EPA-HQ-OAR-2011- 0083. 

What is essential right now: 

· No permitting of any new biomass facility while EPA is developing 

regulations. (Moratorium);

· No expansion of any existing facility during this time;

· No grandfathering of any existing facility under less stringent rules;

Why: 

· Biomass burning is dirtier than coal combustion;

· Biomass incineration is not carbon neutral;

EPA-HQ-OAR-2011-0083-0098.pdf
· Biofuel production for incineration is contributing to higher food costs impacting all, 

but especially impacting disenfranchised communities;

 · Biomass incinerators are getting federal stimulus dollars to site in disenfranchised 

communities; 

· Because of the delay, there will be a rush to permit during the deferment. This will 

make developing and promulgating regulations which are protective of public health and 

the environment virtually impossible;

· Already permitted facilities are likely to be grandfathered in and not subject to more 

stringent rules, creating de facto sacrifice zones in rural, working class, and minority 

communities. 

· Due to slash-and-burn budget proposals targeting health- based regulations 

means that many states will be unable to properly protect public health and the 

environment. 

Additionally: 

Because federal dollars are being used, Environmental Impact Studies should be 

required for each facility. The EIS's must take into consideration potential environmental 

justice impacts, and public health impacts (sensitive communities: elderly, poor, 

children, immune compromised).

Thank you.

Duff Badgley

No Biomass Burn

Seattle, WA

206-283-0621

duff@nobiomassburn.org

www.nobiomassburn.org

===================== ptairwatchers.org =============================

 Breathe Clean! Breathe Healthy!

pt-nobiomass@lists.riseup.net - Discuss! Please keep it on-topic

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Support our work with your tax-deductible donation. Send checks to:

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 - message-footer.txt

EPA-HQ-OAR-2011-0083-0098.pdf
0083 5.9.11 10677_000000.TXT

MessageID: <B82A145D29E04C6AB103D7D479629248@micropact.com>

From: <jferguson@resourcemgt.com>

Sent: 04/06/2011 12:32:14 PM

Subject: Docket ID No. EPA-HQ-OAR-2011-0083

Body: I am writing in support of your proposed rule to defer the regulation of 

carbon dioxide emissions from biogenic sources under the PSD and Title V 

programs. It is sound public policy to step back and evaluate the 

science and public policy reasons to support renewable biomass energy and 

not regulate it in the same manner as fossil fuels. What the science will 

show is that not only is biomass energy sustainable, carbon beneficial, 

domestic, and renewable, but that there are significant unintended 

consequences of regulating biomass energy the same as fossil fuels. The 

science and public policy reasons are best outlined in a letter 113 

scientists wrote to Congress in July 2010 

(www.nafoalliance.org/scientists). 

Here are some key points with supporting references: 

Wood biomass energy is sustainable. History demonstrates that as demand 

for forest products increases so does the volume of trees growing. 

Between 1953-2006, the volume of trees per acre nationwide grew 49% and 

increased in all regions. In addition, forest acreage in the U.S. has 

remained relatively stable over the past 100 years, and forest owners have 

consistently planted more than they harvested since the 1940s. (State of 

America`s Forests. Society of American Foresters. 2007.) This has 

occurred during a period of unprecedented increase in demand for wood 

forest products to meet housing and consumer needs.

Markets for forest products conserve forests for the long term. The 

greatest threat to deforestation is the conversion of private forests to 

more economically competitive, non-forest uses. 57% of U.S. forests are 

privately owned, and forest land must maintain its economic value to 

remain as forests for the long term. Markets for forest products, tax 

liability and the cost of regulation are key considerations when forest 

owners determine the economic viability of forest land ownership. Biomass 

energy can be an important new market to replace other declining markets 

and add economic value to private forest ownership. (American Forests: A 

History of Resiliency and Recovery. Douglas MacCleery. 1996.) 

Demand for biomass energy must be projected realistically. The bottom line 

is that not every announced bioenergy facility will become operational. 

Forisk Consulting, a market-research firm serving the forest products 

industry, developed a basic screening methodology to help determine which 

announced facilities are likely to be operational by 2021. The results 

are updated each month. As of January 30, 2011, Forisk tracked 446 

wood-consuming, announced projects in the continental U.S. These projects 

represent the potential for an additional 123.7 million tons/year of wood 

use by 2021. However, applying Forisk`s viability screen, projects 

representing only 68.5 million tons/year are likely to be online by 2021. 

(see http://www.forisk.com/Forisk-Bioenergy-Research-v-42.html) 

Supply of biomass for energy can be increased sustainably. A 2010 study 

from the University of Georgia and North Carolina State University 

documents that private U.S forests are not as productive as they can be 

because of depressed market prices and reduced manufacturing capacity. 

The authors demonstrate that increased markets for biomass energy can lead 

to increased, sustainable yields from private forestlands. Within 25 

years, growth and production could increase 150% on intensively managed 

lands and 75% on less intensively managed lands. (A Developing Bioenergy 

Market and Its Implications on Forests and Forest Products Markets in the 

United States. Dr. Mike Clutter et. al. 2010. 

Page 1
0083 5.9.11 10677_000000.TXT

http://nafoalliance.org/wp-content/uploads/NAFO-Executive-Summary-Clutter-E

t-Al-Final.pdf). 

Regulating biogenic carbon the same as fossil fuels has several unintended 

consequences, including encouraging fossil fuel, increased greenhouse gas 

emissions from National Forests, and lost U.S. manufacturing jobs. (The 

Unintended Consequences of the EPA Tailoring Rule. Bruce Lippke and Dr. 

Elaine Oneil. 2010. 

http://www.corrim.org/pubs/reports/2010/biomass_vs_fossil/BiomassVSFossilEm

issionsNov2010.pdf )

Regulating biogenic carbon threatens U.S. jobs and renewable energy 

goals. According to a 2010 study, this would conservatively cost between 

12,000-28,000 renewable energy jobs, $18 billion fewer dollars of capital 

investment in renewable energy, and over 5,384 fewer megawatts of 

renewable electricity generation. It would also jeopardize renewable 

energy goals in up to 30 states. (Economic and Regional Impact Analysis 

of the Treatment of Biomass Energy Under the EPA Greenhouse Gas Tailoring 

Rule. Dr. Brooks Mendell and Amanda Hamsley Lang. 2011. 

http://nafoalliance.org/wp-content/uploads/tailoring-rule-economic-impact-s

tudy.pdf). 

The carbon cycle is continuous over time and carbon accounting should 

reflect this. The carbon debt-dividend accounting method proposed by some 

is flawed, because it establishes an arbitrary starting point for the 

ongoing natural carbon cycle. This cycle encompasses all recurring plant 

growth, is constantly in flux and cannot be arbitrarily constrained by 

time and space. (Accounting for Greenhouse Gas Emissions from Wood 

Bioenergy. Dr. Jay O`Laughlin. 2010.)

Carbon accounting should take a national, rather than a stand or plot 

level, approach. Forests are managed across the landscape, not on 

individual plots, so carbon stock changes need to emulate the way forests 

are managed. The U.S. has a well-established system to track changes in 

national forest carbon stocks through the Forest Inventory and Analysis 

program at the U.S. Forest Service. This is the data the EPA relies on 

for its annual inventory of U.S. greenhouse gas emissions and sinks. 

(Biomass Carbon Neutrality. Reid Miner. 2010. 

http://nafoalliance.org/wp-content/uploads/NCASI-Biomass-carbon-neutrality.

pdf) 

Thank you for the opportunity to comment.

Sincerely,

Mr. Joey Ferguson

Regional Manager

Resource Mgmt Service, LLC

67 Greenbriar Ave

Pawleys Island SC 29585

Email: jferguson@resourcemgt.com

Page 2
0083 5.9.11 10677_009937.TXT

MessageID: <IP-0AC2AF90bcd43f950e0847e7a32b74918d32cadf@ip-0AC2AF90>

From: "Ilene Stahl" <greenfieldbiomass@klezperanto.com>

Sent: 05/04/2011 12:13:01 PM

Subject: Biomass Power is Not Carbon Neutral

Body: "Biogenic" CO2 Emissions,

The latest science (quoted below) clearly demonstrates that burning 

forests for electricity is not only NOT "carbon neutral," but actually 

increases the concentration of carbon dioxide in the atmosphere. It is 

past time that the EPA account for the CO2 smokestack emissions associated 

with biomass power.

While the EPA studies this issue, it is important that a moratorium be 

declared on permitting construction of new biomass power incinerators.

"Forest biomass generally emits more greenhouse gases than fossil fuels 

per unit of energy produced."

-Biomass Sustainability and Carbon Policy Study, Manomet Center for 

Conservation Sciences, June 2010:

"Exempting emissions from bio-energy use is improper for greenhouse gas 

regulations...Harvesting existing forests for electricity adds net carbon 

to the air."

-Fixing a critical climate accounting error, Searchinger et. al., Science, 

325:529, October 23, 2009.

"The claim that biomass power is 'carbon neutral' because the new trees 

use the same carbon dioxide to grow that they released when burned is 

false as has been recognized by both US scientists and the 

Intergovernmental Panel on Climate Change on which I serve."

-William Moomaw, Professor of International Environmental Policy and 

Director of the Center for International Environment and Resource Policy 

at Tufts University:

"Carbon dioxide emissions from biomass per unit of energy generated are 

about 1.5 times higher than from coal and 3 to 4 times greater than from 

natural gas."

-Clearcut Disaster: carbon loophole threatens U.S. forests," Environmental 

Working Group, June 2010:

Sincerely,

Ilene Stahl

284 Chapman St

Greenfield, MA 01301

Page 1
0083 5.9.11 10677_000030.TXT

MessageID: <24370065.1304345824580.JavaMail.tomcat@web4.salsalabs.net>

From: Janine Christo <blackbird-1997@hotmail.com>

Sent: 05/02/2011 10:17:04 AM

Subject: EPA-HQ-OAR-2011-0083-0001 – No Moratorium on Biomass Regulations

Body: Dear Administrator Jackson,

I am writing in response to EPA’s solicitation for comments to Docket ID 

No. EPA-HQ-OAR-2011-0083-000. I request that EPA not exempt biogenic CO2 

emissions from burning biomass and other bioenergy sources from regulation 

during a three year long study.

A number of scientific studies have established that – per unit of 

electricity generated – biomass combustion can produce just as much, if 

not more, CO2 emissions as coal combustion. Rather than giving biomass a 

free-pass for three years, EPA should err on the side of caution and 

regulate the CO2 emissions from biomass based on what pollution comes out 

of the smokestack.

I specifically request that while the three year study is underway, EPA 

should not provide permits to new facilities that use biomass in order to 

produce electricity, unless in their decision-making they account for all 

smokestack emissions.

Janine Christo

P.O. box 442

North Kingsville, OH 44068

Page 1
0083 5.9.11 10677_000042.TXT

MessageID: <9615531.1304351668939.JavaMail.www@app339>

From: NRDC<nrdcinfo@nrdconline.org>

Sent: 05/02/2011 11:54:28 AM

Subject: Docket #EPA-HQ-OAR-2011-0083 - Don't defer biomass pollution standards

Body: May 2, 2011

Administrator Jackson and EPA Staff

Dear EPA Staff,

I support the Environmental Protection Agency's authority to enforce

Clean Air Act standards to reduce global warming pollution that harms

human health and the environment. The pollution from biomass energy

sources should be no exception, and I am concerned about the proposal

to defer safeguards for these emissions for the next three years.

A three-year deferral on biomass pollution safeguards would create a

perverse incentive for new and expanded power plants to burn biomass

instead of other fuels. Because the supply of truly sustainable,

low-carbon forestry wastes is extremely limited, expanding biomass

power means burning whole trees. The EPA should not be creating

perverse incentives for burning biomass without safeguards for our

forests.

It would take many decades to recapture the carbon released from

cutting and burning a natural forest for energy. And unlike coal,

living and growing trees continue to absorb carbon from the atmosphere

if left alone, so cutting down and burning trees for energy means

losing this critical environmental service. Burning whole trees in

today's power plants would therefore result in even more global warming

pollution than burning coal or other fossil fuels. And we would lose

forests that provide valuable wildlife habitat, fresh air, clean water

and places to hike and camp.

Only biomass that is carefully chosen, grown responsibly and

efficiently converted into energy can reduce carbon and other pollution

compared to fossil fuels. Instead of giving large power plants a free

pass to indiscriminately burn even the most unsustainable forms of

biomass, the EPA should require big new or expanded power plants to

continue to count all of their carbon emissions, no matter what the

fuel.

Sincerely,

Mr. Bruno Zacke

Richard-Sorge-Strasse 25

Berlin, None 10249

Page 1
file:///J|/Equivio/Case16/Reports/EPA_Report%200083%205.9.11%2010677/10548.TXT[5/9/2011 2:28:57 PM]

MessageID: <456158.86685.qm@web110502.mail.gq1.yahoo.com>

From: Dinda Evans <dindamcp4@yahoo.com>

Sent: 05/05/2011 05:55:22 PM

Subject: docket ID No. EPA-HQ-OARBody: The EPA is taking public comments on proposed draft regulations for 

greenhouse gas emissions, known as the “Tailoring Rule.” But under 

pressure from the biomass industry, EPA is offering biomass incinerators a 

free ride – no permits necessary – for three more years while they study 

the issue...even though CO2 smokestack emissions from burning biomass are 

even worse than coal!

The U.S. Supreme Court has ordered EPA to regulate greenhouse gases, but 

the biomass, waste and timber industries have spent millions getting EPA 

to offer them this three year exemption. Please contact the EPA and demand 

they do proper accounting for biomass incineration!