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General Conformity

General Conformity Training Modules: Appendix B April 5, 2010 Revisions to the Conformity Regulations

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

In the 2010 revisions(27 pp, 287 K, About PDF) to the General Conformity Regulations, EPA identified a number of potential provisions to improve the effectiveness of the regulations while at the same time streamline their implementation. Under the revisions, the basic conformity process remains essentially the same. The revisions deleted unnecessary provisions, provided more options for federal agencies to demonstrate conformity, recognized the status of Indian tribes, and clarified some procedural requirements.

B1 Applicability Analyses

EPA revised the following provisions that affect the applicability analyses:

  • Deleted the test for exempt actions or actions that have emissions below the de minimis levels to determine if the emissions are regionally significant. When EPA promulgated the original General Conformity Regulations in 1993, it included a provision that required exempted actions and actions with emissions below the de minimis levels but considered regionally significant emissions, defined as above 10 percent of the area’s emission inventory, to conduct a full conformity determination. Although federal agencies and third parties routinely evaluated exempt actions and actions with emissions below the de minimis levels, none of the actions were determined to be regionally significant;
  • Included exemption for minor sources with new source review (NSR) permits. The original regulations provided an exemption for major NSR sources but not minor sources;
  • Identified the following as presumed to conform actions:
    • Prescribed fires conducted in accordance with an approved smoke management plan,
    • Emissions within a facility emission budget where the budget has been adopted by the state in accordance with the regulations, and
    • Actions listed by a state agency as presumed to conform.

  • Established a program to allow early emission reductions to create emission reduction credits (ERCs) that can be used to reduce the emissions from future actions; and

  • Established a grace period of one year after an area is designated as nonattainment before conformity is required.

B2 Conformity Demonstrations

EPA is adding a new section that allows alternate schedules for mitigating emissions increases. The mitigation timing approach allows some flexibility for federal agencies and states or tribes to negotiate a program for some emissions mitigation to occur in future years. This approach can be used to accommodate short-term increases in emissions if substantial long-term reduction in emissions will result.

B3 Reporting Requirements

The revised regulations establish the rights of federally recognized Indian tribes to participate in the conformity process and require the federal agency to provide the draft demonstration to any such tribe in a nonattainment or maintenance area.

B4 Procedural Requirements

EPA included the following provisions in the revised regulations to clarify the process:

  • Development of the presumed to conform list;
  • Exemption for the rulemaking process;
  • Extension of the emergency events exemption;
  • Demonstrating conformity beyond the time frame in the SIP/TIP; and
  • Allowing but not requiring states and tribes to adopt a conformity SIP/TIP.