Dump trucks and backhoes filed into Duke Energy’s Dan River power plant Tuesday as officials worked to plug a leaking storage pond that dumped enough coal ash into the river to fill 20 Olympic swimming pools [according to the Charlotte Observer].
Pond water continued to leak from a 48-inch stormwater pipe that broke Sunday, washing at least 50,000 tons of ash carried by 24 million gallons of water into the Dan. Coal ash contains metals that can be toxic at high concentrations.
It’s not clear why the reinforced concrete pipeline broke. Built in the 1960s, it runs beneath the unlined ash pond – the only one of Duke’s 14 North Carolina ash ponds with such a pipe beneath it. A power plant in Indiana also has a pipe under its ash pond.
While Duke has said no downstream problems have been reported, at least one water customer of the Dan River watershed took immediate steps to protect its water supply from any contamination.
Virginia Beach, Va., cut off all pumping from Lake Gaston, a massive downstream reservoir that straddles the state line. The lake also supplies water to the Virginia cities of Norfolk and Chesapeake.