Duke Energy shut down a power plant in Wilmington, N.C., on Friday after a dam at the site breached, allowing coal ash into the nearby Cape Fear River, the company said.
The Environmental Protection Agency links the substances in coal ash — including heavy metals like arsenic and lead — to nervous-system problems, reproductive issues and cancer. It was not immediately clear how much coal ash was moving into the river.
The operation that was closed, Duke’s L.V. Sutton plant, has been a growing concern since last week, when rains associated with Hurricane Florence caused a coal ash landfill at the site to erode, spilling ash onto a roadway. According to the company, 2,000 cubic yards of ash escaped but the spill quickly contained.
Waterkeeper Alliance, an environmental group, disputed that, saying at least some of the coal ash spilled last week entered the environment.
This latest release concerns the two unlined coal ash ponds on site, which contain a combined 2.1 million cubic yards of coal ash, according to a report prepared for Duke Energy this year. That amount of coal ash would fill the Houston Astrodome 1.3 times.
Coal ash is the hazardous powdery substance that remains after burning coal. It has received increased scrutiny since 2008, when the Kingston Fossil Plant in Harriman, Tenn., spilled 5.4 million cubic yards of coal ash into the surrounding environment, triggering a cleanup that cost more than 1 billion dollars.
In 2014 Duke Energy’s Dan River plant in Eden, N.C., spilled 39,000 tons of coal ash into the Dan River, prompting the state to require Duke to close all of its coal ash ponds, a process that is not yet complete.
The L.V. Sutton plant now burns natural gas, but until 2013 it housed a three-unit, 575-megawatt coal-fired plant. The coal ash from that operation remains on site.
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