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  2. General Conformity

General Conformity Training Module 4.2: State and Tribal General Conformity Implementation Plan Revisions

  • Module IV
    State, Local, Tribal
  • 4.1 State, Tribal, and
    Local Involvement
  • 4.2 State and Tribal Conformity
    Implementation Plans

States and Tribes are allowed, but not required, to have their own General Conformity implementation plan revision. If a State or Tribe adopts an implementation plan for their own General Conformity program the plan must be at least as stringent, and must be consistent with, the federal regulations under 40 CFR part 93 subpart B. The State or Tribal program cannot be more stringent than the federal regulations unless the State or Tribes make the requirements applicable to non-federal entities as well.

The State or Tribe can develop their own criteria and procedures so long as they are consistent with subpart B. States or Tribes that already have an approved General Conformity implementation plan revision, or choose to have their own program, can submit a revision to incorporate by reference (IBR) the whole of 40 CFR part 93 subpart B.

Once the plan revision is adopted by the State or Tribe and approved by EPA as an implementation plan revision, federal agencies are obligated to meet the requirements of the State or Tribal plan before considering the requirements of the federal regulations under subpart B. Since the State or Tribal criteria and procedures are approved as part of the implementation plan for the nonattainment or maintenance area, they remain in full force and effect until EPA approves the removal of any parts or portions of the criteria or procedures. 

General Conformity

  • What is General Conformity?
  • Basic Information About the Rule
  • Regulatory Actions
  • Training Modules I - IV
    • Module I: The Basics
    • Module II: Key Concepts
    • Module III: The Details
    • Module IV: State, Local, Tribal
    • Appendix A Sample Emissions Calculations
    • Appendix B 2010 Revisions to the Regulations
    • Glossary for Training Modules
Contact Us about General Conformity
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Last updated on March 20, 2025
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