Air and Radiation EPA420-S-05-007

June 2005

Analysis of and Action on

State of Connecticut

Department of Environmental

Protection’s Request for a

Waiver of the Oxygen Content

Requirement in Federal

Reformulated Gasoline
EPA420-S-05-007

June 2005

Analysis of and Action on State of Connecticut

Department of Environmental Protection’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 “Connecticut RFG area” as it is used in this document means the entire State of

Connecticut and includes the Connecticut State portion of the Hartford-New HavenSpringfield Consolidated Metropolitan Statistical Area (CMSA), the Connecticut State

portion of the New York City CMSA, and the opt-in areas of Litchfield, Hartford,

Middlesex, New London, Tolland, and Windham Counties, Connecticut.

ANALYSIS OF AND ACTION ON 

STATE OF CONNECTICUT DEPARTMENT OF ENVIRONMENTAL PROTECTION’S

REQUEST FOR A WAIVER OF THE OXYGEN CONTENT REQUIREMENT

IN FEDERAL REFORMULATED GASOLINE

I. INTRODUCTION

The Connecticut 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. Connecticut has requested a waiver of the RFG oxygen

content requirement for the Connecticut 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 Connecticut’s request for a waiver, and the basis for EPA’s

determination to deny Connecticut’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 Connecticut’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
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]. 

2

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

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 emission 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. Connecticut’s waiver request

In a letter dated April 22, 2002, from Connecticut Governor John G. Rowland to

then Administrator Whitman, Connecticut expressed intent to submit a waiver request 

under CAA Section 211(k)(2)(B) from the federal RFG oxygen content requirement. In a

letter dated September 29, 2004 from Connecticut Department of Environmental

Protection (DEP) Commissioner Arhtur J. Rocque, Jr., to Assistant Administrator Jeff

Holmstead, Connecticut officially submitted such a request for the Connecticut RFG
4

 Docket OAR-2004-0429-0001.

3

area.4 The submission stated that because MTBE was banned in the State of

Connecticut 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 the

State of Connecticut. DEP 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. DEP further argued that

“increases in these pollutants will immediately interfere with Connecticut’s ability to

attain the National Ambient Air Quality Standard (NAAQS) for both one-hour and eight

hour ozone...and fine particles.”

II. EPA’S ANALYSIS OF THE INFORMATION THAT CONNECTICUT DEP

SUBMITTED

A. Basis for DEP’s request for a waiver

DEP’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

and particulate matter 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 Connecticut prior to its MTBE ban or to non-oxygenated

fuel. 

• Commingling and permeation resulting from ethanol use will increase

VOC emissions compared to MTBE-oxygenated or non-oxygenated RFG.

• 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.

• The transport of ethanol into the Connecticut area would cause an

increase in emissions due to additional ships and barges transporting

ethanol into the Connecticut area for adding to RFG at terminals.

• Fine particulates will increase because the NOx emission performance will

be worse for ethanol blended RFG as compared to the fuel under an

oxygen waiver.
4

B. Major limitations in the information submitted by DEP

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 Connecticut 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.

Connecticut’s submissions included essentially no information or analysis of the

expected fuel properties of RFG with and without a waiver. Connecticut 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 carbon monoxide (CO) or subsequent

conversion of NOx to particulates. NOx, VOCs, and CO each affect ozone to a varying

degree, and their emissions rates could be altered by a waiver. Changes in VOC, NOx,

and CO emissions were not quantified, and the lack of adequate information and

analysis means that even the direction of any change in NOx and VOC is not clear. 

Changes in CO emissions were not addressed.

 

If Connecticut 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 and particulate matter, 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 and particulate matter. 

DEP’s original “intent to submit” letter indicated that they planned to provide this

information. Consequently, EPA responded that we were awaiting Connecticut’s

documentation in support of Connecticut’s plan to request a waiver. DEP did not

provide the information in their official request. 
5 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.

5

 EPA has considered the information that Connecticut has provided which may

be relevant to an analysis of Connecticut’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 Connecticut 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 Connecticut,

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

determination for CO emissions can be made, the change in CO likewise cannot be

quantified with the information provided by DEP.5

III. CONCLUSION

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

would have on ozone or particulate matter levels in Connecticut. This is because: 1)

there are three pollutants whose emission rates could be altered by a waiver (NOx,

VOC and CO) 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; 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. 

In addition, (1) NOx emissions affect PM, (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, (3)
6

no analysis has been provided or performed, and the information before the agency

does not allow an analysis to be performed, on the effect of any NOx emissions

changes on particulate matter. 

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

emissions related to ozone and particulate matter, the information that DEP has

provided fails to clearly demonstrate what effect a waiver would have on ozone or

particulate matter. 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 the

attainment of the ozone or particulate matter NAAQS, and therefore cannot determine

whether compliance with the oxygen requirement for RFG prevents or interferes with

attainment of the ozone or particulate matter NAAQS in the Connecticut RFG area. 

EPA concludes that Connecticut’s request therefore should be denied.