EPA has revised its regulations guiding the preparation of state implementation plans (SIPs). These regulations are found in 40 CFR Part 51. This action revises the minimum reporting frequency requirement for SIPs applicable to source categories listed in Appendix P to 40 CFR Part 51 from quarterly to semiannual. This is generally consistent with the current reporting frequency requirements to which these sources are subject under other programs (e.g., New Source Performance Standards). Each state can—but is not be required to—revise its SIP to allow semiannual reporting for four source categories:

1.         fossil fuel-fired steam generators of more than 250 million BTU per hour heat input;

2.         fluid bed catalytic cracking unit catalyst regenerators at petroleum refineries;

3.         sulfuric acid plants; and

4.         nitric acid plants.

The Clean Air Act requires each state to develop a plan to attain and maintain clean air known as a state implementation plan, or SIP. In general, SIPs must demonstrate how national air quality standards will be achieved, maintained, and enforced. 

Read the final rule in the Federal Register.

Read the proposed rule in the Federal Register.

A summary Fact Sheet is below.

• Fact Sheet: Revisions to Appendix P to 40 CFR Part 51, Concerning Minimum Emission Reporting Requirements in SIPs (PDF)(2 pp, 191 K)