About a half a square mile is covered with sludge.
Coal ash is recycled into products such as cement or placed in secure landfills, but much of it ends up in gravel pits, abandoned mines and unlined landfills — or in ponds like the one that burst in Kingston, Tenn., on Dec. 22. In the Tennessee incident, 5.4 million cubic yards of sludge laced with arsenic and other toxic materials poured over 300 acres — making it one of the nation's worst environmental spills.
The EPA in 2000 decided that coal ash wasn't hazardous waste and left regulation up to the states. The Kingston Fossil Plant was the largest coal-burning power plant in the world when it began operating in 1955. The plant normally consumes about 14,000 tons of coal a day. There are about 600 coal ash disposal sites — about 45 percent of them surface ponds, and the rest landfills. There are about 300 surface ponds at electric power plants like the one in Tennessee.
Coal combustion waste is estimated at more than 129 million tons a year, she said. The problem, she said, is that because of a lack of federal oversight, "we don't know where it goes."
There is coal ash and sludge from the coal plants and there is sludge from the mountain top removal mining. Mining sludge dam broke and killed 125 people at Buffalo Creek. Pictures and article through this link.