On February 19, 2026, the US EPA Administrator signed a final rule entitled, National Emission Standards for Hazardous Air Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating Units: Final Repeal. The rule was published in the Federal Register on February 24, 2026 and becomes effective April 27, 2026. A copy of the final rule is available here. The rule repeals certain amendments to the Mercury and Air Toxics Standards (MATS) Rule published on May 7, 2024. More specifically, the final rule repeals the three (3) MATS amendments listed below.
The filterable particulate matter (fPM) emission standard for existing coal-fired electric utility steam generating units (EGUs), which the EPA revised from 0.030 pounds per million British thermal units (lb/MMBtu) to 0.010 lb/MMBtu;
The compliance demonstration requirement for the fPM emission standard for all coal- and oil-fired EGUs, which the EPA revised from allowing EGU owners and operators to choose between use of quarterly stack testing, use of continuous parametric monitoring systems (CPMS), or use of PM continuous emission monitoring systems (CEMS) to only allowing use of PM CEMS; and
The mercury (Hg) emission standard for existing lignite-fired EGUs, which the EPA revised from 4.0 pounds per trillion British thermal units (lb/TBtu) to 1.2 lb/TBtu.
