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. Photo: TVA Near the TVA powerplant site with a failed ash-disposal cell, dredging of the Emory River is almost complete after 18 months. 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
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.