In the nine days since a coal ash storage basin at Duke Energy’s old Dan River Steam Station spilled an estimated 27 million gallons of water and 82,000 tons of coal ash into the Dan River in Eden, N.C., people in boats and on riverbanks collecting water samples has become a familiar sight.
But there’s more than just water to check for contaminants from the spill, and a U.S. Environmental Protection Agency field team has been pulling sediment samples for analysis as well.
Chris Decker, a member of the river team from the EPA’s region 4 field office in Athens, Ga., was at Abreu-Grogan Park on Monday morning, packing up samples to send in for analysis. He said the team arrived Wednesday and would be pulling samples at least through Friday — this trip.
“We’ll be making return visits for a long time,” Decker said.
Decker’s team is pulling their tests from the 25-mile stretch of the Dan River from Eden, N.C., to Danville; other teams from the EPA and other agencies are spread out along the river to Kerr Lake.
Such teams are EPA first responders to any water-related emergencies, and members of this team have responded to disasters that included Hurricane Katrina, the 2008 coal-ash spill in Tennessee and the 2010 BP oil spill in the Gulf of Mexico, Decker said.
The sediment will be tested for metals, solids and the presence of coal ash from the spill at the EPA environmental research lab in Georgia.
Trish Taylor, the community involvement coordinator for the EPA’s region 3 hazardous site clean up division, confirmed that the EPA has been testing sediment, river water and drinking water along the Dan River since the spill happened.
Now that the immediate need to stop the spill has happened, plans for long-term cleanup can begin, Taylor said.
At the Danville Water Treatment Plant, extra tests to make sure the drinking water remains safe continue, but Barry Dunkley, director of water and wastewater treatment, said conditions on the river have made it possible to cut back on the number of extra tests.
“The material [coal ash] has settled in the river; we’re not seeing it in the intake anymore,” Dunkley said.
Last week, the plant was pulling daily samples of both river and treated water for heavy metal analysis of 15 dangerous metals found in coal ash — such as arsenic, selenium and lead — but since those tests have come back showing the levels are safe, they will cut back to taking them of just the treated water once a week.
Extra tests will be ordered any time it rains, Dunkley said, because that could potentially stir up some of the pollutants that have settled.
National primary drinking water regulations require water treatment plants to test for disinfectants, disinfectant byproducts, inorganic chemicals, microorganisms, organic chemicals and radionuclides.
Dunkley said the normal testing schedule varies depending on the items being tested. Some, like turbidity (the cloudiness of the water) and pH, get tested several times a day, while others are tested quarterly or annually.
“All told, there are about 200 parameters we test for over the course of a year,” Dunkley said.