# 2026-03638: EPA Rolls Back Mercury and Particle Limits for Fossil Fuel Power Plants 2026-03638, National Emission Standards for Hazardous Air Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating Units: Final Repeal, is a Federal Register rule from Environmental Protection Agency published 2026-02-24, effective 2026-04-27; deemed significant under Executive Order 12866 (as of 2026-11-04). - Canonical: https://policyrisk.com/federal-register/2026-03638 - As of: 2026-11-04 - Plain-text twin of the page above; the HTML and this file carry the same facts. ## Facts - Document number: 2026-03638 - Title: National Emission Standards for Hazardous Air Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating Units: Final Repeal - Type: Rule - Agencies: Environmental Protection Agency - Citation: 91 FR 9088 - Published: 2026-02-24 - Effective: 2026-04-27 - Comments close: not stated - Significant: yes (OIRA_API) - Touches household money: no - Regulation identifier numbers: 2060-AW68 - Last updated: 2026-11-04 ## In one line EPA Rolls Back Mercury and Particle Limits for Fossil Fuel Power Plants ## Summary The EPA is rolling back some recent pollution rules for coal- and oil-fired power plants, especially those about tiny particles and mercury emissions. This change affects existing power plants and takes effect on April 27, 2026. It means these plants might have fewer strict limits to follow, potentially saving them money on compliance. ## 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. ## Effects PRIA read - Repeal of tighter fPM limit: benefit, high. The EPA repealed the 2024 change that tightened the filterable particulate matter (fPM) limit for existing coal-fired power plants from 0.030 lb/MMBtu to 0.010 lb/MMBtu. Starting April 27, 2026, affected coal-fired electric utility steam generating units will no longer be required to meet the 0.010… - PM CEMS mandate repealed: benefit, medium. The EPA repealed the 2024 requirement that all coal- and oil-fired EGUs must use particulate matter continuous emissions monitoring systems (PM CEMS) to demonstrate compliance. As of April 27, 2026, owners and operators may again choose among quarterly stack testing, continuous parametric monitorin… - Lignite mercury standard rolled back: benefit, medium. The EPA repealed the 2024 tightened mercury (Hg) standard for existing lignite-fired EGUs that had revised the limit from 4.0 lb/TBtu to 1.2 lb/TBtu. Effective April 27, 2026, the more stringent 1.2 lb/TBtu Hg requirement for lignite units from the 2024 Final Rule is no longer in effect. - Estimated national compliance savings: benefit, high. The EPA estimates this repeal will produce present-value cost savings of $670 million at a 3% discount rate and $490 million at a 7% discount rate over the 2028–2037 timeframe, with total annualized savings of $78 million per year (3% rate) and $69 million per year (7% rate) in 2024 dollars. Those… ## Related documents - [2026-22082](https://policyrisk.com/federal-register/2026-22082): Additional Reconsideration Standards of Performance for New, Reconstructed, and Modified Sources and Emissions Guidelines for Existing Sour…, 2026-10-29 - [2026-21155](https://policyrisk.com/federal-register/2026-21155): Renewable Fuel Standard (RFS) Program: Reallocation of Additional 2025 Small Refinery Exemptions, 2026-10-16 - [2026-20849](https://policyrisk.com/federal-register/2026-20849): Clean Water Act Hazardous Substance Facility Response Plans: Compliance Date Delay and Changes To Reflect Administration Policy, 2026-10-13 - [2026-19071](https://policyrisk.com/federal-register/2026-19071): Partial Repeal of the Carbon Pollution Standards for Fossil Fuel-Fired Electric Generating Units, 2026-09-17 - [2026-19072](https://policyrisk.com/federal-register/2026-19072): Rescission of the Greenhouse Gas Findings for Fossil Fuel-Fired Power Plants and Repeal of Regulations for Power Plant Greenhouse Gas Emiss…, 2026-09-17 - [2026-18317](https://policyrisk.com/federal-register/2026-18317): Updated Definition of “Waters of the United States”, 2026-09-09 ## Sources - [2026-03638 on federalregister.gov](https://www.federalregister.gov/documents/2026/02/24/2026-03638/national-emission-standards-for-hazardous-air-pollutants-coal--and-oil-fired-electric-utility-steam) - [2026-03638 as published (PDF)](https://www.govinfo.gov/content/pkg/FR-2026-02-24/pdf/2026-03638.pdf) ## Related - [Previous: 2026-03630, Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Depa…](https://policyrisk.com/federal-register/2026-03630) - [Next: 2026-03645, Economic Adjustment Assistance for Textile Mills-Payment Rate](https://policyrisk.com/federal-register/2026-03645) - [All Federal Register documents](https://policyrisk.com/federal-register) Source: PRIA, https://policyrisk.com/federal-register/2026-03638 (as of 2026-11-04).