CHARLOTTE — North Carolina's environmental department is investigating whether Duke Energy ash pits are responsible for an orange sheen of contamination that has coated a stretch of the Yadkin River, a state spokesman said Friday.
The action comes one day after environmental groups released test results showing that the problem on the river was caused by leaky Duke waste pits at the Buck Steam Station near Salisbury.
Coal ash contains numerous chemicals that are toxic to humans and wildlife, including arsenic, selenium, and chromium. The groups said their tests showed those substances, as well as others, in the Yadkin at levels exceeding state standards.
The state Department of Environment and Natural Resources took water samples Friday and will take action if it finds any "unpermitted seep or discharge," spokesman Drew Elliot said, adding that he doesn't know how long it will take to get the results.
Duke spokeswoman Erin Culbert said the river is safe, but environmentalists disagreed.
John Suttles, senior attorney for the Southern Environmental Law Center, said the groups told Duke last month about the seeps, but nothing happened. So when they got the test results this week, they decided to tell the public.
"When we saw the numbers — and saw how an extensive an area and how numerous these leaks were — we viewed it as a matter of public safety and health. We felt that we had to get this information out as quickly as we could," he said,
Duke's 33 unlined ash pits across the state have been under intense scrutiny since a February spill at a power plant in Eden coated 70 miles of the Dan River in gray sludge.
North Carolina lawmakers approved new legislation in July requiring Duke to remove its ash at four priority sites within five years. The remaining dumps are to be either removed or capped with a layer of plastic and dirt by 2029.
State officials say Duke's leaky, unlined dumps are contaminating surrounding groundwater and environmentalists have called for all the ash to be removed to lined landfills away from rivers and lakes.
Duke has said it will seek the less expensive option of leaving at least some of the dumps in place, covered with a layer of plastic sheeting and topped with soil to prevent rainwater from seeping through and contaminating the surrounding area.
It still hasn't been determined which option will be used for Buck's three waste pits.
Environmental groups say the ash pits have been leaking for years, but the leaks were largely hidden beneath the river. The seeps were exposed when river levels were lowered to allow for a bridge maintenance project, said Suttles, whose law group represents a coalition of environmental organizations fighting to force Duke to clean up its ash pits.
"This, in effect, pulled the curtain back to confirm what we've been saying for a long time: These coal ash lagoons leak extensively into rivers and groundwater," Suttles said.
Elliot said the discharges had not previously been identified by his department because "they were only visible due to the water level in the lake being lowered about 14 feet." He added that they don't know yet if the problem is from the ash pits.
Culbert said the seeps "contain low levels of constituents, so the Yadkin River would continue to be well protected," adding that "closing basins also will address seeps."
"By the way, the orange color is often caused by iron bacteria, a naturally-occurring and non-harmful bacteria that occur commonly in this area because of iron-rich soils," she said.
But Suttles said that's misleading.
"What they're dealing in is half truths. We do not dispute the fact that the seeps contain iron, or that that is one of the causes of the orange color ... But that's not the whole story," he said, adding that their tests show high levels of other coal ash contaminants that can harm people and the environment.