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Amendments to General Provisions for Exemption from Emission Standards During Periods of Startup, Shutdown, and Malfunction (SSM)

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Rule Summary

This rule amends two provisions in 40 CFR part 63 subpart A that are provided under Clean Air Act (CAA) section 112 National Emission Standards for Hazardous Air Pollutants (NESHAP). The NESHAP General Provisions (40 CFR part 63 subpart A ) contain provisions that, when incorporated by reference within a specific source-category NESHAP, eliminate unnecessary repetition of general information and requirements that often apply (e.g., emission testing, monitoring, recordkeeping, and reporting provisions). The General Provisions have the legal force and effect of emission standards when incorporated by reference into a source-category NESHAP.

In a 2008 decision (Sierra Club v. EPA), the United States Court of Appeals for the District of Columbia Circuit vacated portions of two provisions in the NESHAP General Provisions governing the emissions of hazardous air pollutants (HAP) during periods of startup, shutdown, and malfunction (SSM). Specifically, the court vacated NESHAP General Provisions language that exempted sources from HAP non-opacity and opacity emission standards contained in 40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1). The court held that under section 302(k) of the CAA, emissions standards or limitations must be continuous in nature and that “the SSM exemption violates the CAA's requirement that some section 112 standards apply continuously.”

EPA has taken actions since the decision to amend source-category NESHAP to reflect this vacatur and, with this action, amends the NESHAP General Provisions language.

Rule History

03/05/2021 – Final Rule (pre-publication version)

Additional Resources

Fact Sheet - Amendments to General Provisions for Exemption from Emission Standards During Periods of Startup, Shutdown, and Malfunction

Court Decision: Sierra Club v. EPA, 551 F. 3d 1019 (D.C. Cir. 2008)

(Note: For 508-compliance questions, please contact Michelle Bergin at bergin.michelle@epa.gov.)