By David Zucchino, Los Angeles Times

MONCURE, N.C. — While poring over regulatory documents for Duke Energy coal ash ponds, environmentalists at the Waterkeeper Alliance grew suspicious of how the giant utility was handling the toxic ash waste left over from burning coal.

They sent a team up in an aircraft to photograph Duke’s retired Cape Fear coal-burning power plant and ash ponds in this tiny community in central North Carolina.

The photos revealed what the Waterkeeper Alliance says is evidence that Duke, the nation’s largest electric utility, is deliberately pumping toxic coal ash wastewater from the containment ponds into a canal that feeds into the Cape Fear River, a source of drinking water for downstream cities.

In the photos, two portable pumps and hoses can be seen drawing water from a coal ash pond and dumping into the canal and into nearby woods. According to the environmental group, that is a criminal violation of the Clean Water Act and state laws.

“They were trying to hide it. It was just dumb luck that we caught them at it,” said Peter Harrison, staff attorney for the alliance.

State regulators said the pumping could be illegal.

Duke and state regulators are under intense public and political pressure after the February 2 Duke Energy coal ash spill, which coated the Dan River with toxic coal ash sludge for at least 70 miles in North Carolina and Virginia. Hazardous heavy metals such as arsenic and lead were dumped into the river.

That spill, at a retired Duke Energy coal-fired plant in Eden, N.C., led to allegations by environmental groups that state regulators have been soft on Duke and have ignored coal ash seepage for years from 14 Duke plants in North Carolina. It was the third-worst such spill in U.S. history.

Federal prosecutors have announced a criminal investigation into the relationship between the state agency and Duke Energy. They have said they are seeking evidence of any money or gifts exchanging hands. Officials at the state agency and at Duke Power have been issued subpoenas to appear before a grand jury this week.

In a statement, Duke Energy said the pumps were permitted by state regulators.

“The pumps in question are temporary installations used to lower the water level in those ash basins in order to perform maintenance on equipment in the basins,” the statement said. “This maintenance activity is allowed under our permits and the N.C. Department of Environment and Natural Resources is aware that this work is occurring.”

A spokesman for the state agency, Drew Elliott, said in an email message: “Our inspectors noticed this pumping during an on-site inspection this week, and we are investigating the utility’s actions. While routine maintenance is allowed under the permit, discharge of untreated wastewater could be a violation.”

Elliott said he didn’t know whether the inspectors noticed the pumps before or after the Waterkeeper Alliance took aerial photos. The agency announced March 5 that it would conduct detailed inspections of all coal ash ponds at Duke’s 14 plants, including the Moncure plant.

Harrison called Duke Energy’s explanation “absurd.” He said no state permit would allow a utility to pump coal ash water from ponds because pumping would dredge up toxic heavy metals that settle at the bottom of the ponds.

Photo: Waterkeeper Alliance Inc. via Flickr