salumi. currently there are over one hundred forty billion gallons of coal slurry contained in more than one hundred impoundments in west virginia alone the total quantity of coal slurry in the rest of southern appalachians is. one december twenty second two thousand and eight a coal ash impoundment at the tennessee valley authorities kingston fossil plant failed when an earthen dike broke spilling over one point one billion gallons of coal ash sludge over three hundred acres. coal ash sludge has waste created from the burning of coal at the kingston coal plant it is believed to contain toxic compounds including arsenic and mercury. the tennessee valley authority has meets the cost of the cleanup over eight hundred twenty five million dollars this spill is ten times larger than the exxon valdez spill in alaska and is believed to be america's largest environmental disaster to date with throwing away the next generation's most valuable resource and that is water one of the best sources of water