Air and Radiation EPA420-S-05-006

June 2005

Analysis of and Action on

New York State Department of

Environmental Conservation’s

Request for a Waiver of the

Oxygen Content Requirement

in Federal Reformulated

Gasoline
EPA420-S-05-006

June 2005

Analysis of and Action on New York State

Department of Environmental Conservation’s

Request for a Waiver of the Oxygen Content

Requirement in Federal Reformulated Gasoline

Transportation and Regional Programs Division

Office of Transportation and Air Quality

U.S. Environmental Protection Agency
1 The term “New York RFG area” as it is used in this document means the New York State

portion of the New York City Consolidated Metropolitan Statistical Area (CMSA) and the

opt-in area of Dutchess County, New York.

ANALYSIS OF AND ACTION ON 

NEW YORK STATE DEPARTMENT OF ENVIRONMENTAL CONSERVATION’S

REQUEST FOR A WAIVER OF THE

OXYGEN CONTENT REQUIREMENT IN FEDERAL REFORMULATED GASOLINE

I. INTRODUCTION

The New York reformulated gasoline (RFG) area is required under the Clean Air

Act to use RFG containing 2% oxygen by weight, unless that oxygen content

requirement is waived by EPA. New York has requested a waiver of the RFG oxygen

content requirement for the New York RFG area.1 This document discusses the Clean

Air Act oxygen content requirement for RFG, EPA’s authority to waive that requirement,

the basis for New York’s request for a waiver, and the basis for EPA’s determination to

deny New York’s request. Additional information is available in an accompanying

Technical Support Document. 

A. The RFG Oxygen Content Requirement and EPA’s Waiver Authority

Under the Clean Air Act (“CAA” or “the Act”), 42 U.S.C. § 7545(k)(2)(B), nine

geographic areas in non-attainment for the ozone National Ambient Air Quality

Standards (NAAQS), as well as other areas that subsequently are reclassified as

severe ozone nonattainment areas, are required to use reformulated gasoline. CAA §§

211(k)(10)(D), 211(k)(5). Certain other ozone non-attainment areas may “opt-in” to the

RFG program as a means of addressing their ozone non-attainment problems. CAA

§211(k)(6). The Act specifies certain gasoline content requirements for RFG. CAA §

211(k)(2). Of particular importance for New York’s request is the Act’s requirement 

concerning the oxygen content of RFG and EPA’s authority to waive that requirement.

Section 211(k)(2)(B) of the Act provides:

The oxygen content of the [reformulated] gasoline shall equal or exceed

2.0 percent by weight (subject to a testing tolerance established by the

Administrator) except as otherwise required by this Act. The Administrator

may waive, in whole or in part, the application of this subparagraph for

any ozone nonattainment area upon a determination by the Administrator

that compliance with such requirement would prevent or interfere with

attainment by the area of a national primary ambient air quality standard. 
2

 Docket A-2000-10, III-A-1.

3 For further discussion of EPA’s interpretation of the authority to grant a waiver under

section 211(k)(2)(B), see Appendix A of Docket A-2000-10, II-B-1.

4

 Docket OAR-2003-0004, II.D.1.

2

Thus, EPA has discretion under this section to waive the oxygen content

requirement if it determines that compliance with the oxygen content requirement would

prevent or interfere with attainment of a primary National Ambient Air Quality Standard

(NAAQS) in an ozone nonattainment area. This section requires, at a minimum, that an

applicant seeking a waiver must clearly demonstrate the impact of a waiver for each

applicable NAAQS. See Davis v. EPA, 348 F.3d 772, 779-80 (9th Cir. 2003)(affirming

EPA’s evidentiary standard in the context of EPA’s denial of California’s waiver

request.)2 EPA may take into consideration other available information in evaluating a

request for a waiver.3

A key threshold question before the Agency when considering such a request is

whether there has been a clear demonstration of the air quality impacts of a waiver of

the RFG oxygen content requirement. To address the air quality impacts of a waiver,

one must, as a technical matter, consider the gasoline fuel properties of the RFG that

would likely be sold in the area with and without an oxygen content waiver. From this

information, one must then evaluate the impact that a change in fuel properties would

produce on emissions of pollutants. The expected change in emissions of pollutants

associated with those different RFG blends is needed to evaluate the impact of a

waiver on attainment of a NAAQS. All relevant categories of emissions need to be

considered.

EPA cannot make a determination of interference with or prevention of

attainment of any NAAQS due to compliance with the oxygen content requirement

unless the projected emissions impacts of a waiver are analyzed for each applicable

NAAQS. Absent such an analysis, EPA is not able to determine whether a waiver

would aid, hinder, or have no effect on attainment of a NAAQS.

B. New York’s waiver request

In a letter dated January 6, 2003 from New York State Department of

Environmental Conservation (DEC) Commissioner Erin Crotty to then Administrator

Whitman, New York officially requested a waiver under CAA Section 211(k)(2)(B) from

the federal RFG oxygen content requirement for the New York RFG area.4

 The

submission stated that because MTBE would be banned in the State of New York

beginning January 1, 2004, and because of the Act’s oxygen content requirement for

RFG, ethanol would be used as an oxygenate in the RFG areas in New York State. 
5 Docket OAR-2003-0004, Document II.C.1.

6 Docket OAR-2003-0004, Document II.D.6.

7 DEC’s stated reasons for not providing the information requested by EPA, and EPA’s

responses to those statements (that are not otherwise addressed in the TSD), are set

forth in Appendix B to the Technical Support Document.

3

DEC asserted that the use of ethanol as a replacement for MTBE in RFG would result

in an increase in Volatile Organic Compounds (VOCs), and oxides of nitrogen (NOx)

during the summer ozone season. DEC further argued that “increases in these

pollutants will immediately interfere with New York’s ability to demonstrate reasonable

progress to attain and maintain the federal ozone standard...”

EPA determined that DEC’s submission did not contain sufficient information and 

failed to address the requirements specified in the statute. EPA notified NY that

technical and supporting information was needed for EPA to evaluate the merits of the

request. In a letter to DEC dated April 1, 2003, EPA requested clarification and

additional information.5

A subsequent submission dated December 12, 2003 from DEC acknowledged

EPA’s April 1, 2003 request for additional information.6 DEC provided some additional

information in support of its waiver request with this correspondence, but generally did

not provide the information requested by EPA, for reasons set forth in its letter.7

II. EPA’S ANALYSIS OF THE INFORMATION THAT NEW YORK DEC SUBMITTED

A. Basis for DEC’s request for a waiver

DEC’s request for a waiver is based primarily on its contention that use of

ethanol-oxygenated reformulated gasoline will interfere with attainment of the ozone

NAAQS because:

• The NOx and VOC emissions performance of ethanol-oxygenated RFG

will be worse than the emissions performance of the MTBE-oxygenated

RFG supplied to New York prior to its MTBE ban. 

• Commingling and permeation resulting from ethanol use will increase

VOC emissions compared to MTBE-oxygenated RFG.
4

• Ethanol-oxygenated RFG will not provide the NOx reduction benefits

expected under the RFG program because the Complex Model does not

fully capture the effects of oxygenates on vehicle emissions of NOx.

• Relaxation of the RFG VOC performance standard for 10 percent ethanol

blends, or granting of a 1 psi volatility waiver for 10 percent ethanol blends

could increase VOC emissions.

• The transport of ethanol into the New York area would cause an increase

in emissions due to additional ships and barges transporting ethanol into

the New York area for adding to RFG at terminals.

B. Major limitations in the information submitted by DEC

As discussed above, a key threshold technical issue in evaluating a waiver

request is to evaluate the emissions impact of a waiver. The emissions impact of a

waiver is basically a comparison of emissions with a waiver (“waiver”) to emissions

without a waiver (“no waiver”). This comparison is needed to clearly demonstrate

whether a waiver would aid, hinder, or have no effect on attainment of a NAAQS. 

Certain information is required in order to make a quantitative estimate, or even

a reasonably certain qualitative directional estimate, of the emissions changes that a

waiver might produce. This information includes knowledge of certain emission-related

properties of the reformulated gasoline that would be supplied to New York with and

without a waiver. Models relating these fuel properties to vehicle emissions would then

be used to estimate percent differences in emissions between the “no waiver” and

“waiver” conditions. Additionally, on-road and off-road gasoline emission inventory data

are needed in order to convert relative (%) changes to absolute (tons/day) changes. 

Inventory information may be necessary even to perform a directional analysis. The

need for this information is described in detail in the accompanying Technical Support

Document.

New York’s submissions included almost no information or analysis of the

expected fuel properties of RFG with and without a waiver. New York did not provide

sufficient information or analysis to show either quantitative or directional estimates of

the emissions differences between “no waiver” and a “waiver” for the pollutants

contributing to ozone formation, NOx, VOCs and CO. Each of these three pollutants

affect ozone to a varying degree, and their emissions rates could be altered by a

waiver. While New York’s submissions did contain quantitative estimates of certain

VOC emission changes that could be associated with ethanol use compared to MTBE

use, these estimates were of little use even to estimate the net directional change that a

waiver would produce in VOC emissions, for several reasons which are discussed in
8 For example, certain other potential VOC emissions changes which could occur were not

quantified, and New York included estimates of VOC emission increases based on

unsupported assumptions about increases in gasoline Reid Vapor Pressure (RVP).

5

the TSD.8 Changes in NOx emissions were not quantified, and the lack of adequate

information and analysis means that even the direction of any change in NOx is not

clear. Changes in CO emissions were not addressed. 

 

If New York had provided information and analysis on the change in fuel

properties and associated emissions that a waiver would be expected to produce, and

the resulting impact on ozone, EPA would be in a position to thoroughly review the

basis for these estimates (fuel property estimation and emission modeling

methodology), and evaluate the estimated impact a waiver might have on ambient

ozone. 

DEC’s original waiver submission did not provide quantitative estimates of the

“no waiver” to “waiver” emission changes, as well as the underlying information

necessary to make such estimates. Consequently, EPA asked for additional

information and analyses to estimate 1) the effect a waiver would have on the

properties of New York reformulated gasoline, and 2) the effect these changes in fuel

properties would have on emissions from highway and off-road vehicles and equipment. 

DEC has not provided the requested information. 

 EPA has considered the information that New York has provided which may be

relevant to an analysis of New York’s waiver request. EPA has determined as

described in the Technical Support Document, that the relevant no-waiver to waiver

comparison cannot be made either qualitatively or quantitatively. In making this

evaluation, EPA has considered the information provided by New York with regard to

the potential effect of a waiver on each of the pollutants, NOx, VOC and CO, for both

on-road and off-road gasoline vehicles and engines.

In order to evaluate the adequacy of the information submitted by New York, we

have identified the information on fuel properties, vehicle fleets (e.g., on-road versus

off-road, older technology vehicles versus newer technology, etc.), and emission

sources (e.g., exhaust, “as blended” evaporative, commingling and permeation-related)

that would need to be provided to conduct an adequate waiver/no-waiver analysis. We

have also identified emissions models and other information necessary to make the

relevant emission estimates that could be utilized to make a waiver/no-waiver

comparison.

Based on the available information, EPA has concluded that neither the

magnitude nor even the direction of the NOx and VOC changes that would occur with a

waiver can be determined using the information provided. Although a gross directional
9 CO plays a far less important role in ozone formation that NOx or VOC. Thus, even

though a gross directional determination can be made, such a determination provides

little useful information in making a judgement about the net impact on ozone formation

from a waiver.

10 New York has not raised any issue concerning interference with attainment of the

particulate matter (PM) NAAQS. However, our conclusions regarding the PM NAAQS

would be the same as those regarding the ozone NAAQS, i.e., New York has provided

insufficient information to clearly demonstrate what effect, if any, a waiver would have on

PM. This is because New York has not provided sufficient information to determine PMrelated emissions for the no waiver and waiver comparison.

6

determination for carbon monoxide (CO) emissions can be made, the change in CO

likewise cannot be quantified with the information provided by DEC.9

III. CONCLUSION

The information that DEC has provided fails to demonstrate what effect a waiver

would have on ozone levels in New York. This is because: 1) there are three pollutants

whose emission rates could be altered by a waiver (NOx, CO and VOC) and all three

affect ozone formation to varying degrees; 2) the lack of information on fuel qualities

with and without a waiver and the lack of other relevant and necessary information

precludes even a directional estimate of the impact of a waiver on NOx and VOC

emissions; 3) the best estimate of the net impact of a waiver on CO emissions is that

CO emissions would be greater with a waiver than without, but the difference cannot

be quantified; and 4) no analysis has been provided or performed, and the information

before the agency does not allow an analysis to be performed, on the combined effect

of these emissions changes on ozone.

 Since no determination can be made regarding the overall effect of a waiver on

ozone-related emissions, the information that DEC has provided fails to clearly

demonstrate what effect a waiver would have on ozone. Since this threshold

demonstration has not been made, EPA is not able to determine whether a waiver

would aid, hinder, or have no effect on attainment of the ozone NAAQS, and therefore

cannot determine whether compliance with the oxygen requirement for RFG prevents or

interferes with attainment of the ozone NAAQS in the New York RFG area. EPA

concludes that New York’s request therefore should be denied.10