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General Conformity

  • Introduction to General Conformity

    General Conformity prohibits a federal agency from interfering with the ability of a State or Tribe to achieve the National Ambient Air Quality Standards (NAAQS).  Assurance of conformity to the purpose of an implementation plan shall be an affirmative responsibility of the federal agency.  

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Historical record of EPA revisions to the General Conformity regulations

  • Read more about the regulatory history of the regulations.
  • View the General Conformity de minimis tables.
  • Full text of the Conformity Regulations - 40 CFR part 93

Modeling Clarification Memorandum for Secondary Pollutants and Nitrogen Dioxide      

Learn About General Conformity 

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Contact Us about General Conformity to ask a question, provide feedback, or report a problem.
Last updated on April 29, 2025
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