The U.S. Army Corps of Engineers office in Louisville, Ky., is taking comment until May 23 on a Section 404 Clean Water Act permit application from Kentucky Power related to a coal ash impoundment at the partially shut Big Sandy coal plant located near Louisa in Lawrence County, Kentucky.
The 800-MW Big Sandy Unit 2 was shut last year as part of a wave of American Electric Power (NYSE: AEP) coal unit retirements due to the federal Mercury and Air Toxics Standards. The other coal unit at the plant, Unit 1, is being converted to burn natural gas.
As a result of this move away from coal at the Big Sandy site, Kentucky Power would no longer need to wet-sluice coal ash waste at the nearby Big Sandy Fly Ash Pond. Per federal regulations for wet coal combustion residue (CCR) impoundments, the applicant plans to close the pond by capping the ash in place, said the Corps.
The existing fly ash pond would be graded and filled as part of a cap system. To install this system, 70.4 cubic yards of earthen material (on-site excavated) would be used to fill 2,376 linear feet of 38 stream channels outside the normal pool elevation of the pond (i.e., the cap system would raise the grade of the existing pond and extend into the lower reaches of these channels). Further, the pond’s existing dam and saddle dam would be excavated and replaced, resulting in 0.29 acre of impacts to three wetlands and 842 linear feet of two stream channels. An estimated 150.9 cubic yards of earthen material and concrete would be used to fill these waters. Finally, through the excavation of borrow material needed for the cap system, 0.1 acre of one open-water would be impacted.