In addition to Hurricane Florence’s devastating harm to people, pets and livestock, the storm also highlighted the vulnerability of coal ash impoundments to severe flooding. As rivers rose, staff with the Waterkeeper Alliance — a nonprofit organization that coordinates several groups stewarding affected waterways — monitored area rivers, taking photos and collecting water samples.
Heavy rains first breached a coal ash impoundment at Duke Energy’s L.V. Sutton power plant near Wilmington, N.C., on Sept. 15, discharging coal waste and water into Sutton Lake. On Sept. 21, the dam separating Sutton Lake from the Cape Fear River failed, discharging an unknown amount of coal ash and related wastewater.
At Duke Energy’s H.F. Lee power plant near Goldsboro, three coal ash impoundments that were already closed with an earthen cap were submerged in floodwaters.
The waterkeepers documented arsenic levels 18 times higher than the state drinking water standard in the Neuse River’s floodwaters above the submerged coal ash impoundments. But samples taken at downstream Neuse River locations by the N.C. Dept. of Environmental Quality and Duke Energy revealed heavy metal levels within state water quality standards.
Similar discrepencies were reported regarding coal ash in the Cape Fear River. On Oct. 3, the Waterkeeper Association released lab results from water sampled in the Cape Fear River on Sept. 21 that show arsenic levels 71 times higher than the state drinking water standard. The results showed elevated levels of other heavy metals, with some of the waterkeepers’ samples varying widely.
The following day, the N.C. DEQ released lab resuts from Sept. 22 and several later dates showing heavy metal levels within legal limits, with the exception of copper, which was also found in high levels upstream of the Sutton power plant. And Duke Energy reported that its river water samples from Sept. 18 to 21 showed that the ash’s impact on water quality was negligible. Avner Vengosh, a water quality scientist at Duke University, told news outlets that those involved should be sampling river-bottom sediment for more reliable measurements, since high floods can dilute contaminants.
In South Carolina, a feared coal ash spill was avoided when the Waccamaw River crested at 21.2 feet, just below the 22-foot dam surrounding Santee Cooper’s 200,000-ton coal ash impoundment that is awaiting cleanup. In preparation, Santee Cooper installed an additional temporary, inflatable dam and pumped water into the ash pit to equalize pressure as the river rose.
Also in September, North Carolina regulators held hearings on the state’s proposed new coal ash rules.
“Any coal ash rules for North Carolina’s state program should make it clear that Duke Energy cannot leave its coal ash sitting in groundwater and in impoundments,” said Ridge Graham, North Carolina field coordinator for Appalachian Voices, the publisher of this newspaper.
Contaminants such as boron, hexavalent chromium and vanadium are not covered under the new rules, which Graham says also weaken the state’s ability to push for corrective action in instances of groundwater pollution.
At a September public hearing in Reidsville, N.C., Appalachian Voices Social Work Intern Sarah Mathis drew a connection between the problems related to coal ash storage and Hurricane Florence to projections of future storms made more severe by climate change.
“We must plan for the reality of tomorrow and examine locations based on a larger floodplain mapping standard,” Mathis said. “The end of storing ash in open pits beside our rivers must be now.”
The N.C. DEQ accepted public comments on the rule through Oct. 15.
On Aug. 21, the U.S. Court of Appeals for the D.C. circuit ruled that the 2015 Obama-era rule governing the disposal of coal ash does not go far enough in protecting the health of communities and the environment. The court held that the rule is insufficient to protect against leaks from unlined or poorly lined storage pits and should not have exempted coal ash ponds at closed power plants from the 2015 regulations.
The federal court decision follows the U.S. Environmental Protection Agency’s July release of new coal ash rules that are weaker than the Obama administration’s rules. The finding casts increased doubt over the legality of the Trump administration’s new, less stringent version.
— By Molly Moore