The U.S. Environmental Protection Agency will announce in the Nov. 29 Federal Register that on Nov 10, EPA Administrator Gina McCarthy signed an order rejecting an air permit issued by Tennessee regulators for the coal-fired Bull Run power plant of the Tennessee Valley Authority.
McCarthy granted a petition to object to a Clean Air Act title V operating permit issued by the Tennessee Department of Environment and Conservation (TDEC) to TVA. The Nov. 10 order constituted a final action on a petition submitted by Sierra Club and Environmental Integrity Project in September 2015.
The petitioners alleged that the permit, issued in August 2015, was not consistent with the CAA because it lacks sufficient monitoring to assure compliance with the opacity limit established pursuant to Tennessee Comprehensive Rules & Regulations.
Bull Run is single-boiler supercritical coal-fired plant with a nameplate capacity or 950 MW. It is located in Clinton, Anderson County, Tennessee. The facility's title V permit covers the coal-fired boiler and three auxiliary boilers, ash and coal handling processes, limestone handling, a hydrated lime injection system, and emergency diesel engine fire pumps.
The coal-fired boiler is equipped with an electrostatic precipitator and a wet scrubber, and has a continuous opacity monitoring system located downstream from the ESP and upstream from the wet scrubber. This boiler is subject to a particulate matter emission limit of 0.030 pounds per million British thermal units, and has been operating with PM continuous emissions monitors since May 2013.
McCarthy wrote that the petitioners have demonstrated that the permit and permit record are inadequate to assure compliance with a state implementation plan opacity limit. The EPA observed that the permit already contains monitoring and other control requirements that appear sufficient to show compliance with the SIP opacity limit, but the permit would need to be revised to expressly link such compliance assurance measures with the SIP opacity limit. Specifically, a permit condition already requires the installation and operation of PM CEMS, which could be used to assure compliance with the SIP opacity limit.
McCarthy said the permit could be revised to state that compliance with the SIP opacity limit is demonstrated if PM emissions do not exceed a 0.030 lb/MMBtu heat input limit using PM CEMS. The permit could also continue to require biannual visual observations as a secondary check that both the PM control device and PM CEMS are operating properly. Finally, TDEC also may consider other methods for demonstrating compliance with the permit's opacity limit.