The Tennessee Valley Authority will permanently store on-site coal ash that is recovered during the second phase of its cleanup of a failed dredge cell at its Kingston powerplant in Harriman, Tenn. The U.S. Environmental Protection Agency has approved the plan, which TVA announced on May 18.
The first phase of the cleanup, removing coal ash from the nearby Emory River, is wrapping up, with more than 3.32 million cu yd of ash removed from the river to date. More than 5.4 million cu yd of coal ash was released on Dec. 22, 2008, after the plant’s storage cell failed. TVA and EPA have announced that the Emory River, which flows by the plant, will re-open for use on May 29.
Barbara Martocci, a TVA spokeswoman, says the utility has not yet decided how to handle contracting for the phase-two work. EPA says it expects fieldwork on that phase to begin in late May. Pasadena, Calif.-based Jacobs Engineering Group Inc. is managing the cleanup.
The on-site storage plan was the least expensive of three options that TVA and EPA were considering. The work—estimated to take four years to complete at a cost of $268.2 million—involves removing about 2.5 million cu yd of coal ash that spilled into Swan Pond next to the plant site and returning the area to its pre-spill condition.
Waste recovered during the cleanup’s first phase was removed from the river, then dried and shipped by rail to a landfill in Alabama. Options for phase two also included shipping all—or some—of the ash to that landfill, but that could cost more than $700 million.
TVA will dry the ash and place it on an engineered foundation of sand, gravel and geo-fabric enclosed by an 22,600-linear-ft wall, 60 ft to 70 ft deep, built of cement and subsurface soil. When completed, the storage area will be capped with layers of clay and topsoil. TVA says EPA’s proposed rules for regulating ash, issued on May 4, do not affect the cleanup plan.