ON THE DAN RIVER, N.C. — Hundreds of workers at a Duke Energy power plant scrambled to plug a hole in a pipe at the bottom of a 27-acre pond that has leaked up to 82,000 tons of coal ash mixed with 27 million gallons of contaminated water into the Dan River since it was discovered Sunday.
Officials at Duke, the nation’s largest electricity provider, say they do not know when the leak will be contained, though the flow has decreased significantly as the pond has emptied.
Environmental regulators are awaiting test results to determine if there is any hazard to people or wildlife. Coal ash is known to contain toxic chemicals, including lead, arsenic, mercury and radioactive uranium.
Twenty miles downstream from the spill site and across the state line in Danville, Va., officials said they were successfully filtering out contaminants in the drinking water. Officials in Virginia Beach stopped drawing water from Lake Gaston, a major reservoir fed by the Dan.
Personnel from Duke Energy and state and federal agencies, including the Environmental Protection Agency and the United States Fish and Wildlife Service, traveled the river on Wednesday, collecting water and sediment samples.
Environmentalists and regulators have been warning for years that the 31 ash ponds at Duke’s power plants in North Carolina had the potential for calamity.
At the Dan River plant, the waste pond was expanded more than 40 years ago over an older storm water drainage pipe. That pipe, which empties into the river, collapsed last weekend, draining the pond above.