HARRIMAN — A retention pond wall collapsed early this morning at the Tennessee Valley Authority’s Kingston steam plant, releasing a mixture of water and fly ash that flooded nearly a dozen homes and caused a train wreck.
More than 500 million gallons of it. And: What is fly ash?
Fly ash is the finest of coal ash particles. It is called "fly" ash because it is transported from the combustion chamber by exhaust gases. Fly ash is the fine powder formed from the mineral matter in coal, consisting of the noncombustible matter in coal plus a small amount of carbon that remains from incomplete combustion.
Coal ash can carry toxic substances that include mercury, arsenic and lead, according to a federal study. The amount of poisons in TVA's ashy wastes that could irritate skin, trigger allergies and even cause cancer or neurological problems could not be determined Monday, officials said.
More on that here.