Environmental regulators have approved Duke Energy’s plan for a lined landfill at a coastal North Carolina power plant so coal ash can be deposited there.

The state Department of Environmental Quality announced Friday the permit for the nation’s largest electric utility to operate the landfill at the Sutton Steam Plant outside Wilmington.

The landfill will collect material from the now-closed coal-fired operations sitting in two unlined basins at Sutton. Duke Energy already was ordered to close the two basins in 2019. Sutton’s ash so far has been transported to fill an old Chatham County clay mine.

Duke Energy previously accepted a $7 million fine for groundwater pollution at Sutton and other coal-fired plants. The department says the utility will monitor water quality around the landfill as part of the permit.