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Regulatory

Announcement

Office of Transportation

and Air quality

EPA420-F-04-043

June 2004

Transportation Conformity Final

Rule: Conformity Amendments for

the New 8-hour Ozone and PM2.5

National Ambient Air Quality

Standards, Response to March 1999

Court Decision, and Additional Rule

Changes

The U.S. Environmental Protection Agency (EPA) is revising the

transportation conformity rule to: 1) provide transportation conformity

regulations for the new 8-hour ozone and fine particulate matter (PM2.5)

national ambient air quality standards (NAAQS); 2) incorporate existing

federal guidance that is consistent with a U.S. Court of Appeals

decision; and 3) streamline and improve EPA’s existing transportation

conformity rule. Transportation conformity is a Clean Air Act

requirement that ensures that federally-supported highway and transit

project activities are consistent with (“conform to”) the purpose of a

state air quality implementation plan (SIP). Conformity ensures that

public health is protected by early consideration of transportation

decisions in cities with air quality challenges.

Background and Description of Final Rule

EPA developed this final rule in response to two proposals that were

published last year. On November 5, 2003, EPA published a proposal to
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address conformity requirements under the new ozone and PM2.5 air

quality standards (68 FR 62690). On June 30, 2003, EPA proposed to

incorporate existing federal guidance into the conformity rule consistent

with a March 2, 1999, U.S. Circuit Court of Appeals decision (68 FR

38974). EPA is now combining both of these rulemaking efforts into one

final rule to provide a complete package to all existing and new nonattainment and maintenance areas. The following paragraphs provide

further information on the main issues addressed in this final conformity

rule.

First, we are conducting this rulemaking in the context of EPA’s broader

strategies for implementing the new air quality standards. EPA’s nonattainment area designations for the new 8-hour ozone standard are effective on June 15, 2004, and EPA anticipates designating areas for the new

PM2.5 standard in December 2004. Through this final rule, EPA is providing clear guidance and procedures for implementing conformity for

both new standards.

The final rule describes when conformity first applies in new ozone and

PM2.5 nonattainment areas. The Clean Air Act and transportation conformity rule allow a one-year grace period before conformity applies for

the new standards, and this grace period begins upon the effective date

of EPA’s nonattainment designation for either new standard.

The final rule also describes the general requirements for doing conformity under the new standards, such as the regional emissions test(s) that

would apply before and after SIP motor vehicle emissions budgets are

established for the new standards. A motor vehicle emissions budget (or

“budget”) is the level of emissions from cars and trucks that the state has

determined to be consistent with local air quality goals. Through this

final rule, EPA is providing certain 8-hour ozone areas and all PM2.5

areas a choice between what conformity emissions test can be used for

ensuring that transportation decisions are consistent with clean air. EPA

is also providing additional flexibility for areas with less severe air

quality problems. SIP budgets for the existing 1-hour ozone standard

will be used for 8-hour ozone conformity prior to establishing 8-hour

SIPs, unless other tests are deemed more appropriate through an area’s

interagency consultation process. Using existing 1-hour ozone SIP

budgets in the interim will ensure that progress continues towards

achieving the new ozone standard.
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Second, the final rule incorporates existing EPA and Department of

Transportation (DOT) guidance for a March 2, 1999, decision from the

U.S. Court of Appeals for the District of Columbia Circuit. In Environmental Defense Fund v. EPA, et al., 167 F. 3d 641, D.C. Cir. 1999, the

U.S. Court of Appeals ruled against EPA on several provisions of the

transportation conformity regulations. One significant rule revision

resulting from the court decision affects the procedures for advancing

highway and transit projects during a conformity lapse. These projects

may proceed, consistent with the court decision, during a conformity

lapse as long as they have received the appropriate federal approvals

before the lapse. A conformity lapse occurs when an area does not meet

conformity deadlines on time. The final rule also establishes in regulation

EPA’s existing administrative process for determining whether the motor

vehicle emissions budgets in SIP submissions are appropriate to use in

conformity determinations.

Finally, EPA is making several other changes to clarify the conformity

regulations and improve implementation. Of particular interest is a final

rule revision that streamlines the current requirements for redetermining

conformity after certain SIP actions have occurred (e.g., after EPA’s

approval of a SIP). This revision ensures that a new conformity determination is required only for SIP budgets that have never been used in the

conformity process. Another significant revision implements the Clean

Air Act in a more reasonable and practicable manner by allowing transportation planners to base regional emissions analyses on assumptions

available at the beginning of the conformity process. Under the current

conformity rule, transportation agencies must include the latest planning

assumptions available at the end of the conformity process (i.e., after a

regional analysis has already been completed).

Key Elements of the Final Rule

• The final rule directly supports EPA’s broader strategy for implementing the new ozone and PM2.5 standards. Providing clear guidance on how to implement transportation conformity under the new

standards will ensure that transportation and air quality planning is

coordinated and that clean air is achieved.

• EPA has worked closely with DOT in the development of all aspects

of this final rule. Additionally, EPA consulted with state and local

transportation and air quality agencies and interest groups in its

initial development of the conformity options for the new standards

that were proposed in November 2003.
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• The final rule provides guidance for when conformity first applies

in new ozone and PM2.5 nonattainment areas. It also describes the

general requirements for doing conformity under the new standards,

such as what conformity emissions test(s) would apply before and

after a SIP is established for the new standards. EPA is also providing additional flexibility for implementing these tests in areas with

less severe air quality.

• EPA notes that the final rule does not address transportation conformity requirements for PM2.5 precursors and PM hot-spot analyses.

EPA will consider conformity requirements for addressing PM2.5

precursors after the close of the comment period on the EPA’s soon

to be proposed general PM2.5 implementation rule. EPA will also be

publishing a supplemental notice of proposed rulemaking to request

additional comment on options related to new PM2.5 and existing

PM10 hot-spot requirements for individual transportation projects.

EPA intends to finalize any conformity provisions for PM2.5 precursors and PM hot-spots before PM2.5 designations are effective.

• This final rule also revises the transportation conformity regulations

to incorporate current guidance issued by EPA and DOT to implement a March 1999 U.S. Court of Appeals decision. This final rule

provides clear guidance and rules that will assist all nonattainment

and maintenance areas in implementing conformity consistent with

the court’s ruling. State and local governments have been successfully implementing this guidance for almost five years.

• EPA is making other rule changes to clarify and improve the existing conformity regulations in existing and new areas. Of particular

interest are final rule amendments for streamlining when a conformity determination is needed and using latest planning assumptions

in a more practicable manner.

Health and Environmental Impacts

The final rule will not result in any change in health and environmental

benefits of the conformity program. This rulemaking will ensure that

conformity is practicably implemented for the new and current air quality standards in a manner consistent with the Clean Air Act’s public

health and environmental goals.
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For More Information

You can access the final rule and related documents electronically on the

Office of Transportation and Air Quality Web site at:

www.epa.gov/otaq/transp/traqconf.htm

For further information about the final rule, please contact:

Meg Patulski

U.S. Environmental Protection Agency

Transportation and Regional Programs Division

2000 Traverwood Drive

Ann Arbor, MI 48105

(734) 214-4842

E-mail: patulski.meg@epa.gov

or

Rudy Kapichak

U.S. Environmental Protection Agency

Transportation and Regional Programs Division

2000 Traverwood Drive

Ann Arbor, MI 48105

(734) 214-4574

E-mail: kapichak.rudolph@epa.gov

or

Laura Berry

U.S. Environmental Protection Agency

Transportation and Regional Programs Division

2000 Traverwood Drive

Ann Arbor, MI 48105

(734) 214-4858

E-mail: berry.laura@epa.gov