The EPA is proposing amendments to several New Source Performance Standards (NSPS) and

National Emission Standards for Hazardous Air Pollutants (NESHAP) under the Clean Air Act (CAA). Specifically, the EPA is proposing to remove the affirmative defense provisions associated with violation of emission standards due to malfunctions. These provisions are being proposed for removal because the EPA finds that they are inconsistent with a D.C. Circuit Court decision that vacated affirmative defense provisions in one of the EPA’s CAA regulations, and because the EPA finds that the reasoning in the decision applies equally to other CAA rules. Since the court decision, the EPA has been removing affirmative defense provisions from CAA rules when they were otherwise revised or amended. This action proposes to remove the remaining affirmative defense provisions more efficiently.


Comments. Comments must be received on or before August 8, 2024.

Public hearing. If anyone contacts us requesting a public hearing on or before June 29, 2024, we will hold a virtual public hearing. See SUPPLEMENTARY INFORMATION for information on requesting and registering for a public hearing.


You may send comments, identified by Docket ID No. EPA-HQ-OAR-2023-0509, by any of the following methods:

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