Reclassification of Major Sources as Area Sources under Clean Air Act

Review of Final Rule Reclassification of Major Sources as Area Sources Under Section 112 of the Clean Air Act Overview for AWMA Information Exchange December 7, 2023

Outline Regulatory History of Reclassifications in the National Emissions Standards for Hazardous Air Pollutants (NESHAP) Program Overview of Proposed Requirements Next Steps 2

Clean Air Act section 112 Major and Area Sources Area Sources: any stationary source of hazardous air pollutants that is not a major source Major Sources: any stationary source or group of stationary sources located within a contiguous area and under common control that emits or has the potential to emit considering controls, in the aggregate, 10 tons per year or more of any hazardous air pollutant or 25 tons per year or more of any combination of hazardous air pollutants 3

History of Reclassifications Sources could not reclassify after the first substantive compliance date of a major source NESHAP Policy laid out through a memorandum 1995 Once in Always In (OIAI) Policy Sources could reclassify from major source to area source at any time Policy laid out through a memorandum 2018 Major MACT to Area (MM2A) Policy Codified the 2018 policy through notice and comment rulemaking 2020 MM2A Rulemaking January 20, 2021 EO directed EPA to identify actions from the prior few years that should be reviewed, revised, or rescinded. 2020 MM2A rulemaking identified under EO 13990 Executive Order 13990 ADD A FOOTER 4

Current MM2A Framework Sources that were previously emitting well below the major source thresholds can reclassify and potentially emit up to the major source thresholds, depending on applicable area source requirements Sources can reclassify from major source status to area source status at any time by limiting their emissions and potential to emit (PTE) below the major source thresholds (10 tons per year individual HAP or 25 tons per year total HAP) 5

September 27, 2023 Proposal Proposed review of 2020 final MM2A rule adds conditions for reclassification Safeguards Upon reclassification, sources must continue to limit emissions to what was allowed under the previous major source NESHAP by either: Continuing to meet the same emissions limits that were in place prior to reclassification; or Comply with subpart-specific requirements for reclassified sources in a category; or Comply with emission standards that a source demonstrates to permit authority are at least as stringent as previously applicable major source limits Federal Enforceability Limits taken to reclassify from major source status to area source status must be federally enforceable Enforceable by the Administrator and citizens under the CAA or other Federal statute 6

Who Does This Apply To? Any Sources that have reclassified since January 25, 2018 Requested comments on: Whether these requirements should only apply moving forward from effective date of final rule? How long sources that have already reclassified should be given to comply? How long sources that reclassify in the future should be given to comply? 7

Next Steps Proposed rule published in the Federal Register on September 27, 2023 (88 FR 33636) 45 day public comment period (ended November 13, 2023) Docket: EPA-HQ-OAR-2023-0330 Target final rule signature in mid-May 2024 Anticipating OMB interagency review of final rule (up to 90 days) prior to final rule signature 8

Questions? Nathan Topham topham.nathan@epa.gov 919-541-0483