EPA Rolls Back Mercury and Particle Limits for Fossil Fuel Power Plants
Published Date: 2/24/2026
Rule
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.
Analyzed Economic Effects
4 provisions identified: 4 benefits, 0 costs, 0 mixed.
Repeal of tighter fPM limit
The EPA repealed the 2024 change that tightened the filterable particulate matter (fPM) limit for existing coal-fired power plants from 0.030 lb/MMBtu to 0.010 lb/MMBtu.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 lb/MMBtu fPM standard established by the 2024 Final Rule.
Estimated national compliance savings
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 Those savings reflect reduced compliance costs for the regulated coal- and oil-fired EGU sector resulting from the repealed 2024 amendments.
PM CEMS mandate repealed
The EPA repealed the 2024 requirement that all coal- and oil-fired EGUs must use particulate matter continuous emissions monitoring systems (PM CEMS) to demonstrate compliance.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 monitoring systems (CPMS), or PM CEMS for demonstrating compliance with the fPM standard.
Lignite mercury standard rolled back
The EPA repealed the 2024 tightened mercury (Hg) standard for existing lignite-fired EGUs that had revised the limit from 4.0 lb/TBtu to 1.2 lb/TBtu. Effective April 27, 2026, the more stringent 1.2 lb/TBtu Hg requirement for lignite units from the 2024 Final Rule is no longer in effect.
Personalized for You
How does this regulation affect your finances?
Personalize government policy and PRIA will tell you what this federal register document means for your household, plus every other regulation we track. PRIA reads each provision against your financial profile to show you exactly what matters to your wallet.
Key Dates
Department and Agencies
Related Federal Register Documents
2026-18317, Updated Definition of “Waters of the United States”
The purpose of this supplemental notice of proposed rulemaking is for the U.S. Environmental Protection Agency (EPA) and the Department of the Army ("the agencies") to supplement and seek additional comment on certain aspects of an earlier proposal, published on November 20, 2025, to revise the regulations defining the scope of waters federally covered under the Clean Water Act in light of the U.S. Supreme Court's 2023 decision in Sackett v. Environmental Protection Agency. As stated in the agencies' November 20, 2025 Notice of Proposed Rulemaking (NPRM), the agencies intend for this rulemaking to provide greater regulatory certainty and increase Clean Water Act program predictability and consistency by clarifying the definition of "waters of the United States." After consideration of the public comments received on the NPRM, the agencies are issuing this notice to supplement the NPRM with additional regulatory options on certain aspects of the proposed rule.
2026-14112, Amendments and Nonconformance Penalties for Model Year 2027 and Later Heavy-Duty Highway Engines and Amendments to Inducement Provisions for SCR-Equipped Diesel Engines
Starting with model year 2027, the EPA is updating rules for big truck engines to make sure they last longer and pollute less. They’re also letting engine makers pay penalties if their engines don’t meet standards, and tightening rules for special pollution-control systems on diesel engines. These changes affect truck and engine makers and kick in soon, with public feedback due by August 29, 2026.
2026-13667, Minor New Source Review Program Air Permitting Public Participation Requirements for State Implementation Plans
The EPA wants to give states more freedom to decide how much public input is needed when approving small air pollution sources or changes. This means local air agencies can tailor public participation to fit their community’s needs while still protecting air quality. If you’re involved in air permits, watch for comment deadlines and possible virtual hearings this summer!
2026-13263, Revisions To Establish the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6) for Public Water Systems
The EPA is rolling out the sixth Unregulated Contaminant Monitoring Rule (UCMR 6) to check for new, sneaky chemicals in public drinking water. Big water systems serving 3,300+ people and some smaller ones will test for 30 different contaminants, including certain PFAS and pesticides, to keep our water safe. Comments and feedback are open until late August 2026, and the EPA will host fun online meetings to chat about the plan!
2026-12927, U.S. Ecology Nevada, Inc. High Mercury Subcategory Wastes Land Disposal Restrictions Variance
The EPA is giving U.S. Ecology Nevada a special green light to handle and dispose of high-mercury waste a bit differently than usual. This means mercury waste treated in Pennsylvania can now be safely sent to U.S. Ecology’s Nevada site for disposal under new rules starting July 27, 2026. This change helps protect people and the environment while keeping mercury waste management efficient and cost-effective.
2026-11047, National Emission Standards for Hazardous Air Pollutants From Hazardous Waste Combustors: Residual Risk and Technology Review
The EPA just updated rules for places that burn hazardous waste, like incinerators and boilers, to keep the air safe and clean. They confirmed current standards work well but added new limits on harmful gases like hydrogen fluoride and hydrogen cyanide. These changes start June 3, 2026, and include easier electronic reporting and some new rules for startup and shutdown times—helping protect health without big costs.
Previous / Next Documents
Previous: 2026-03630, Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures; Miscellaneous Amendments
Starting February 24, 2026, the FAA is updating how pilots approach and take off from certain airports to keep flights safe and smooth. These changes affect pilots and airports by adjusting flight paths and safety rules due to new tech and obstacles. No big costs here—just smarter, safer skies for everyone flying under instrument rules!
Next: 2026-03645, Economic Adjustment Assistance for Textile Mills-Payment Rate
The USDA is boosting the payment rate for the Economic Adjustment Assistance for Textile Mills program from 3 to 5 cents per pound of upland cotton, starting August 1, 2025. This means eligible U.S. textile mills get more financial help to upgrade their equipment and facilities. The new rule kicks in officially on February 24, 2026, giving mills a bigger boost to grow and modernize their operations.