From NYTimes
A coal ash spill that blanketed residential neighborhoods and contaminated nearby rivers in Roane County, Tenn., earlier this week is more than three times larger than initially estimated, the Tennessee Valley Authority said on Thursday.
Coal ash, a byproduct of burning coal, contains toxic heavy metals like arsenic, lead and selenium that can cause cancer and neurological problems.
Authority officials initially said that about 1.7 million cubic yards of wet coal ash had spilled when the earthen retaining wall of an ash pond breached, but on Thursday they released the results of an aerial survey that showed the actual amount was 5.4 million cubic yards, or enough to flood more than 3,000 acres one foot deep. The amount now said to have been spilled is larger than the amount the Authority initially said was in the pond, 2.6 million cubic yards...
The spill occurred at the Kingston Fossil Plant, one of the authority's largest electrical generating sites, located on the banks of the Emory River about 40 miles west of Knoxville.