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Mercury and Air Toxics Standards

Final Subcategory of Certain Existing Electric Utility Steam Generating Units That Fire Coal Refuse

After evaluating information on the acid gas hazardous air pollutant emissions from electric utility steam generating units (EGUs) that burn eastern bituminous coal refuse (EBCR), EPA has established a new subcategory in the Mercury and Air Toxics Standards for these units. Coal refuse includes low-quality coal mixed with rock, clay and other material. It is usually piled near coal mines.  EPA also is establishing emission standards for these facilities to control acid gas hazardous air pollutant emissions. The new subcategory and emission standards will affect six existing EGUs that burn EBCR.  All are small units operating in Pennsylvania or West Virginia.  As a result of this final rule, EPA does not expect emissions to increase above current levels.

A summary fact sheet and EPA's costs and benefits analysis are available below. 

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