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Technology Transfer Network - OAR Policy and Guidance

General Conformity Regulations

Note: EPA no longer updates this information, but it may be useful as a reference or resource.


Background: Section 176(c) of the Clean Air Act prohibits Federal entities from taking actions in nonattainment or maintenance areas which do not conform to the State implementation plan (SIP) for the attainment and maintenance of the national ambient air quality standards (NAAQS). Therefore, the purpose of conformity is to (1) ensure Federal activities do not interfere with the budgets in the SIPs; (2) ensure actions do not cause or contribute to new violations, and (3) ensure attainment and maintenance of the NAAQS. In November 1993, EPA promulgated two sets of regulations to implement section 176(c). First, on November 24, EPA promulgated the Transportation Conformity Regulations (applicable to highways and mass transit) to establish the criteria and procedures for determining that transportation plans, programs, and projects which are funded under title 23 U.S. C. or the Federal Transit Act conform with the SIP (58 FR 62188). Then, on November 30, EPA promulgated regulations, known as the General Conformity Regulations (applicable to everything else), to ensure that other Federal actions also conformed to the SIPs (58 FR 63214).

     With respect to General Conformity, all Federal Actions are covered unless otherwise exempt, e.g. actions covered by transportation conformity, actions with clearly de minimis emissions, exempt actions listed in rule, or actions covered by a Presumed to Conform demo(approved list). Conformity can be demonstrated by : (1) showing emission increases are included in SIP; (2) State agrees to include increases in SIP; (3) areas without SIPs , no new violations of NAAQS and/or no increase in frequency/severity of violations; (4) Offsets, and (5) Mitigation. Some emissions are excluded from conformity determination, such as those already subject to new source review; those covered by CERCLA or compliance with other environmental laws, actions not reasonable foreseeable, and those for which the Agency has no continuing program responsibility.

From the listing below, find the file you would like to download. The available file formats are represented by icons on the right side of the listing. Click on the icon that represents the file format you wish to receive. For an explanation of file formats and their icons, see our TTNWeb File Types.

Related Policy & Guidance

      Airport Emission Reduction Guidance - September 30, 2004
This is an announcement of an exciting new program to reduce emissions from airport vehicles and ingrastructure. Under this program, the Federal Aviation Administrations (FAA) will approve funding of projects to voluntarily reduce emissions at airports. In turn, the airport will receive emission reduction credits that can be used for demonstrating conformity under the General Conformity program or as new source review offsets.
PDF file
      To learn more about the FAA's Voluntary Airport Low Emissions (VALE) probram, go to their website at Exit EPA disclaimer http://www.faa.gov/arp/environmental/VALE/Index.cfm

      General Conformity Guidance for Airports: Questions and Answers - September 25, 2002
The Federal Aviation Administration (FAA) and the Environmental Protection Agency (EPA) formed a stakeholders group to address airport air quality improvements, particularly the reduction of nitrogen oxides (NOx) emissions. One issue raised by airport operators was the need for more specific guidance to airports on the implementation of the General Conformity Regulations. In response, the FAA and the EPA have developed the following guidance in consultation with many organizations, including airport operators, airlines, and State air quality agencies
PDF file
      General Conformity Guidance: Questions and Answers - July 13, 1994
Composite of frequently asked questions. Issues raised initially at General Conformity Workshop held in Virginia on March 7-8, 1994
PDF file
      General Conformity Guidance: Questions and Answers - October 19, 1994
Additional Questions and Answers - Applicability, Bubbling Activities, and Transportation Conformity (attach appropriate file)
PDF file
      Region IX Memorandum to David Kessler of FAA, January 25, 1996
Additional comments on Final Environmental Impact Statement and CAA conformity determination for the Burbank-Glendale-Pasadena Airport Land Acquisition and Terminal Replacement Project, Los Angeles Co., CA - Applicability Determination & Calculation regarding whether or not De Minimis action. - use of year 2010.
PDF file


Related Links:

      Federal Aviation Administration (FAA)
www.faa.gov  Exit EPA disclaimer
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      Bureau of Land Management (BLM)
www.blm.gov/nstc/air/index.html Exit EPA disclaimer
HTML file
      Transportation Conformity
HTML file
      National Park Service
www2.nature.nps.gov/ard Exit EPA disclaimer
HTML file
      Department of Defense
www.DENIX.osd.mil Exit EPA disclaimer
HTML file

EPA Contacts: Tom Coda - phone (919) 541-3037; e-mail coda.tom@epa.gov

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