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NEPA and Transportation/Air Quality Conformity


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Suggested Citation:
Shaheen, Susan A., Francisca Mar, Randall L. Guensler (1994) NEPA and Transportation/Air Quality Conformity. Institute of Transportation Studies, University of California, Davis, Presentation Series UCD-ITS-RP-94-38

Proceedings, Meeting of the Transportation Research Board Committee on Transportation and Air Quality (A1F03)

The Conformity Rule, adopted in November 1993, by the U.S. Environmental Protection Agency under the requirements of Section 176(c)(4) of the Clean Air Act, establishes strict procedures for determining conformity of transportation plans to state air quality management plans. Conformity requirements apply to all transportation plans, programs, and projects, funded or approved under title 23 U.S.C. or the Federal Transit Act. The Conformity Rule requires that transportation planning agencies apply transportation demand and emissions models to demonstrate that transportation plans and all projects contained in a plan will not exceed the allowable emissions budget established in the air quality management plan and will not cause a violation of local air quality standards. This paper addresses the relationships among the National Environmental Policy Act (NEPA), the California Environmental Quality Act (CEQA), and the new conformity requirements. The need to make concurrent NEPA [/CEQA] and conformity determinations is supported by five arguments: 1) the legislative history of conformity indicates that project conformity determinations be made during the NEPA process; 2) general NEPA requirements specify coordination between environmental processes; 3) the level of technical detail required for NEPA [/CEQA] and conformity are similar; 4) unless conformity is taken into account during the NEPA [/CEQA] analysis, the alternatives and mitigation measures generated may result in a negative conformity determination; and 5) public comment periods, unless coordinated, could run consecutively rather than concurrently, potentially delaying project implementation. This paper also includes a discussion of two additional issues pertinent to NEPA [/CEQA] and to conformity: 1) interagency consultation and 2) the potential for citizen suits.