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General Conformity

General Conformity Training Module 1.1: What and Where

Words that are shown in bold and italics are defined in the Glossary.

1.1.1 What is General Conformity?

General conformity is a process required by the Clean Air Act (CAA) , which establishes the framework for improving air quality to protect public health and the environment. The goal of general conformity is to ensure that actions conducted or sponsored by federal agencies are consistent with State air quality goals. These air quality goals are tied to states meeting the National Ambient Air Quality Standards (NAAQS), requirements that are established by the U.S. Environmental Protection Agency (EPA) and are designed to protect human health and the environment.

Each state develops a State Implementation Plan, or SIP, which includes the state’s strategy for attaining or maintaining the NAAQS, the modeling that demonstrates attainment or maintenance, and the various rules, regulations, and programs that provide the necessary air pollutant emissions reductions. On tribal lands, federally recognized Indian tribes can develop their own tribal implementation plans (TIPs), similar to SIPs. If the state or tribe fails to submit a required plan, EPA can promulgate a plan known as a federal implementation plan (FIP).

The conformity process ensures that emissions of air pollutants from planned federal activities would not affect the state’s or tribe’s ability to achieve the clean air goal of meeting the NAAQS. The General Conformity Regulations are found at 40 CFR part 93, Subpart B. EPA maintains a General Conformity website

Specifically, section 176(c) of the CAA requires that federal projects conform to the purpose of the SIP, meaning that federal activities will not cause new violations of the NAAQS, increase the frequency or severity of NAAQS violations, or delay timely attainment of the NAAQS or any interim milestone. Federal activities must also conform to tribal implementation plans (TIP) and federal implementation plans (FIP), where applicable. General conformity is mainly an emission-based system

The general conformity program is an emission-based system; i.e., the program requires emissions to be evaluated and addressed as necessary. The regulations require federal agencies taking or sponsoring an action in certain areas to ensure that increased air pollution emissions from that action conform with the current, approved SIP. This includes estimating both direct and indirect emissions that are likely to occur.

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1.1.2 What actions are covered by General Conformity?

General conformity covers a wide variety of federal activities. A federal activity is generally an action that requires either federal funding and/or federal approval. Even if a project is not federally-funded, there may be federal approvals such as permits that are needed.

1.1.3 Where does General Conformity apply?

The General Conformity Regulations do not apply to every area of the country. Rather, the requirements only apply in nonattainment and maintenance areas. A nonattainment area is an area designated by EPA as not meeting a NAAQS. A maintenance area is an area that was once designated as nonattainment but is currently meeting and maintaining the standard. EPA, in partnership with the states, is responsible for the designation of areas as nonattainment and redesignating them once they achieve the NAAQS. Information on where nonattainment and maintenance areas are located can be found on EPA’s Green Book website. On the site, you can search by pollutant, designation status, or county. You can also contact your EPA Regional office for more information on nonattainment and maintenance areas in your state.

1.1.4 In what cases does General Conformity not apply?

Some actions are exempt from the general conformity requirements, including actions: 

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