{"abstract":"The U.S. Environmental Protection Agency (EPA) is finalizing the repeal of specific amendments to the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Coal- and Oil-Fired Electric Utility Steam Generating Units (EGUs), commonly referred to as the Mercury and Air Toxics Standards (MATS), that were promulgated on May 7, 2024. Specifically, the EPA is repealing the revised filterable particulate matter (fPM) emission standard, which serves as a surrogate for non-mercury hazardous air pollutant (HAP) metals for existing coal- fired EGUs; the revised fPM emission standard compliance demonstration requirements; and the revised mercury (Hg) emission standard for lignite-fired EGUs. The EPA is also making technical, non-substantive clarifications to electronic reporting requirements.","action":"Final rule.","agencies":[{"raw_name":"ENVIRONMENTAL PROTECTION AGENCY","name":"Environmental Protection Agency","id":145,"url":"https://www.federalregister.gov/agencies/environmental-protection-agency","json_url":"https://www.federalregister.gov/api/v1/agencies/145","parent_id":null,"slug":"environmental-protection-agency"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2026/02/24/2026-03638.html","cfr_references":[{"chapter":null,"citation_url":null,"part":63,"title":40}],"citation":"91 FR 9088","comment_url":null,"comments_close_on":null,"correction_of":null,"corrections":[],"dates":"The final rule is effective on April 27, 2026. The Director of the Federal Register (FR) approved incorporation by reference (IBR) of certain publications listed in the rule on April 16, 2012 and May 30, 2023.","disposition_notes":null,"docket_ids":["EPA-HQ-OAR-2018-0794","FRL-6716.4-02-OAR"],"dockets":[{"supporting_documents":[{"title":"Measuring the Impacts of Teachers II: Teacher Value-Added and Student Outcomes in Adulthood.","document_id":"EPA-HQ-OAR-2018-0794-6941"},{"title":"Emergent Risks and Key Vulnerabilities In Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change","document_id":"EPA-HQ-OAR-2018-0794-6939"},{"title":"NEEDS for EPA's Power Sector Modeling Platform 2023.","document_id":"EPA-HQ-OAR-2018-0794-6924"},{"title":"Documentation of changes made during OMB Review Under EO 12866 - MATS Review of the RTR Final Rulemaking. E-mail for Passback #3. 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