RALEIGH, N.C. (AP) — Conservationists and regulators are at odds over how much coal ash was swept away by flooding during Hurricane Matthew — state inspectors say it would fit in the bed of a pickup truck while a watchdog group argues it's a much larger spill.
Waterkeeper Alliance said it took boats down the Neuse River earlier this week, collected samples and photographed thick gray muck in the water near the H.F. Lee plant near Goldsboro, as well as trees coated in rings of a chalky substance. They said it appears to be fly ash and is evidence of a large coal ash spill.
Duke Energy acknowledged that the material is a coal-burning byproduct carried off by the floodwaters that flowed over three inactive coal ash basins, but said it's a safe form of the residue.
Duke and the state Department of Environmental Quality said the discovery doesn't change the conclusions of state inspectors who visited the site.
"It's unfortunate that a political group masquerading as environmentalists is deliberately trying to mislead the public," Tom Reeder, assistant secretary of the environmental department, said in an email.
Since a 2014 coal ash spill at a different plant along the Dan River, North Carolina has begun pursuing stronger regulations and enforcement of coal ash. Legislators required the company to clean up unlined coal ash pits by 2029.
Duke Energy said Friday that floodwater from the Neuse River had covered the three basins at the plant after Matthew inundated part of the state with more than a foot of rain, but the basins were planted with grass, shrubs and trees. They said at the time that some coal ash was carried away by the flooding.
The Department of Environmental Quality issued a statement on Wednesday saying its inspectors returned to the site on Monday and identified the material as cenospheres, adding that the substances are "inert and non-toxic." Duke said the substance is largely made of silica and alumina.
Duke said it was working with the state to determine if cleanup is necessary.
For its part, Waterkeeper Alliance accused Duke Energy of downplaying what it called a "large spill" from one or more basins holding millions of tons of coal ash.
"When a raging river floods over 1 million tons of coal ash, you're obviously going to get more than a pickup truck's worth of ash polluting the river," said Waterkeeper Alliance staff attorney Pete Harrison.
The group asked Lonnie Leithold, a professor at N.C. State University who studies sediments, to examine a sample of the material it gathered.
"We looked at it under a microscope; we also took some photographs of it. It's clearly not natural sediment," said Leithold, adding that she had no prior connection to the environmental group. "It's clearly fly ash. Very pure. They gathered it floating on the water, and showed me photos of it up the trees."