National Emission Standards for Hazardous Air Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating Units-Subcategory of Certain Existing Electric Utility Steam Generating Units Firing Eastern Bituminous Coal Refuse for Emissions of Acid Gas Hazardous Air Pollutants

The U.S. Environmental Protection Agency (EPA) is taking final action establishing a subcategory of certain existing electric utility steam generating units (EGUs) firing eastern bituminous coal refuse (EBCR) for acid gas hazardous air pollutant (HAP) emissions that was noticed in a February 7, 2019, proposed rule titled "National Emission Standards for Hazardous Air Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating Units--Reconsideration of Supplemental Finding and Residual Risk and Technology Review" (2019 Proposal). After consideration of public comments, the EPA has determined that there is a need for such a subcategory under the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Coal- and Oil-Fired EGUs, commonly known as the Mercury and Air Toxics Standards (MATS), and the Agency is establishing acid gas HAP emission standards applicable only to the new subcategory. The EPA's final decisions on the other two distinct actions in the 2019 Proposal (i.e., reconsideration of the 2016 Supplemental Finding that it is appropriate and necessary to regulate EGUs under Clean Air Act (CAA) section 112 and the residual risk and technology review of MATS) will be announced in a separate final action.