The Tennessee Valley Authority expects it will cost about $2 billion to excavate leaking coal-ash storage ponds at its Cumberland River power plant, near Nashville. In an Aug. 4 order, a U.S. district court judge directed the federal power producer to remove coal-ash slurry from multiple unlined ponds to dry storage at a landfill.
The utility estimates there are more than 10 million cu yd of the waste suspended in water at the Gallatin plant, said spokesman Scott Brooks. That is at least double the amount that was stored at its Kingston plant, which in 2008 spilled 5.4 million gallons of waste across farmland and into the Clinch River. While that spill was caused by an impoundment collapse, Gallatin ponds currently are leaking into the groundwater and flowing to the river through the limestone and karst terrain that underlies them. Between 1970 and 1978, about 27 billion gallons of wastewater flowed from the karst aquifer to the river, the order noted. The first of the 976-MW plant’s four units was built in 1953.