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Unlined and Dangerous: Duke Energy’s 32 Coal Ash Ponds in North Carolina Pose a Threat to Groundwater

Duke Energy’s coal ash pond in Eden, N.C., which dumped 39,000 tons of poisonous sludge and slurry into the Dan River on Feb. 2 — the third-largest such spill in U.S. history — has refocused national attention on the environmental damage these holding ponds can render. But the damage isn’t just confined to when the...

Coal ash pulled from the bottom of the Dan River near the site of the Duke Energy spill in Eden, N.C. (Photo courtesy of Dan River Basin Association)

Duke Energy’s coal ash pond in Eden, N.C., which dumped 39,000 tons of poisonous sludge and slurry into the Dan River on Feb. 2 — the third-largest such spill in U.S. history — has refocused national attention on the environmental damage these holding ponds can render.

But the damage isn’t just confined to when the sludge leaks into busted storm-water drainage pipes that never should have been running under the ponds to begin with, like the situation in Eden. It’s quite possible the damage from coal ash ponds is ongoing even in the absence of accidental spills.

“These coal ash ponds are unlined, and people don’t realize that,” said Dean Naujoks, the Yadkin Riverkeeper who has been monitoring the Dan River spill. “They are continuously leaching arsenic, chromium, cadmium, mercury, all kinds of toxic heavy metals, into the ground and eventually into groundwater. Duke Energy has 32 of these ponds on 14 sites around the state, and every one of them is unlined. Every one of them is a threat to groundwater.”

Naujoks points out that municipal landfills, where we send our garbage, are lined and capped when full. It would not be legal to build a landfill adjacent to a river.

“Yet all over the state, we have toxic waste stored in giant farm ponds on the banks of our rivers,” he said. “The state knows this, but it hasn’t done one darn thing to address the problem. The state is afraid of Duke Energy and afraid to take the action necessary to protect the public and the environment.”

Given the public outrage and outcry, not to mention the regular and intense local and national media scrutiny of the state’s response to the Dan River coal ash spill, the less-than-aggressive position of the N.C. Department of Environmental Resources (DENR) might be starting to budge.

Last Friday, DENR announced it would cite Duke Energy for violations of environmental standards in regards to the spill in Eden. And on Monday, DENR cited five power plants owned by Duke Energy for violating water pollution laws. The citations charge that Duke Energy failed to obtain storm-water permits under federal law for the plants.

UPDATE: Significant’y, a state judge in Raleigh now wants DENR to takes a closer look at the unlined coal-ash ponds that environmentalists like Naujoks have been raising red flags over for years. According to news reports late Thursday, “Duke Energy must take ‘immediate action’ to stop toxins leaking from coal ash ponds at its North Carolina power plants and develop a plan to clean up contaminated groundwater at the sites, a Superior Court judge ruled Thursday. Environmental groups hailed the ruling as a first step toward possibly cleaning up the 31 ash ponds at Duke’s 14 current or retired coal-fired power plants across the state.”

Meanwhile, one environmental group, the Dan River Basin Association, isn’t waiting for the state to assess the damage on the Dan. It’s moving ahead with its own independent testing.

Using proceeds from a recent fundraiser, Jenny Edwards, a program manager for the Dan River Basin Association in Rockingham County, said the group will establish testing sites of river-bottom aquatic life — so-called macroinvertebrates — up and downstream from the spill.

Life on the river bottom

coal ash spill
A bottom-dwelling stonefly coated by the Duke Energy coal ash spill on the Dan River in Eden, N.C. (Photo courtesy of the Dan River Basin Association).

On the Dan, determining the health of low-lying river creatures such as mussels, clams, crawfish and dragonflies will determine the health of the fish in the river, and later, the birds and animals that feed on those fish. The fear, said Brian Williams, also a Dan River Basin Association program manager, is that the entire food chain along the upper Dan could be imperiled by the presence of coal ash and its poisonous heavy metals. (The Dan River stretches some 200 miles; about 70 miles is affected by the spill.)

“We are now picking 20 sites for this testing,” Williams said. “We want to get some data quickly to establish baselines above and below the spill. But it’s going to take a couple of years before we see some trends and can start to tell the impact on that part of the river.”

Already, though, Williams described the river bottom on the Dan a mile or two below the spill as a virtual “kill zone” for macroinvertebrates because of the amount of toxic sludge that’s settled. At the spill site, there is a coal ash bar some five feet thick and 75 feet long. Coal ash has been detected along the river bottom some 70 miles eastward downstream — all the way to the John Kerr Reservoir north of Raleigh.

Because of that hazard, the N.C. Department of Health and Human Resources has posted warnings for everyone to stay off the Dan River downstream from the spill and not to eat fish or crustaceans pulled for the waters.

Dean Naujoks, the Yadkin Riverkeeper, cautioned  that people should not grow complacent if they hear that water skimmed from the surface of the Dan is barely polluted as it nears Danville, Va., some 20 miles downstream from the spill site.

“You can treat that water for drinking, as the City of Danville is doing, and it will be OK,” said Naujoks, holding up a clear container filled with coal-ash sludge. “But at lower levels and on the bottom, the toxins will be accumulating in the aquatic system. It’s very likely that this is an environmental problem that will get worse over time.”

He added that the potential impact on agriculture — where farmers pull water from the Dan for irrigation — is also concern that needs to be monitored..

Justin Catanoso is a journalist based in Greensboro, N.C. He is director of journalism at Wake Forest University.


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Meet the Author

Justin Catanoso
Justin Catanoso is a North Carolina-based journalist with 30 years of experience in covering health care, science, economic development and business. He is a Pulitzer Prize nominee and winner of the Science-in-Society Award for his coverage of the tobacco industry in the early 1990s. He has published travel stories from the U.S., Italy, Austria, Thailand and Canada. After 13 years as founding executive editor of The Business Journal in Greensboro, N.C., he is now director of journalism at Wake Forest University in Winston-Salem, N.C.