EDEN, N.C. -- Duke Energy is making plans to build a pair of landfills to store millions of tons of coal ash from two North Carolina power plants. The company will submit permits to construct the landfills at the Dan River Steam Station in Eden and the Sutton Plant in Wilmington.

Duke Energy has wrestled with what to do with the coal ash from the two retired power plants since the spill of thousands of tons of ash into the Dan River in February 2014. The company says it will store more than 6 million tons of ash dry in fully-lined landfills at both sites using industry-proven technologies.

"They will feature multiple layers of protective lining that will effectively contain the coal ash,” said Jeff Brooks, a company spokesperson. “This lining will be both underneath the coal ash and on top of it, essentially cutting it off from the surrounding soil and separating it from groundwater."

A Dan River environmental group says the landfill idea has merit.

"We do think that it's a good thing that the coal ash is staying underneath the purview of Duke Energy,” said Jenny Edwards, a program manager for the Dan River Basin Association. “That means they'll still be responsible for that."

Plans already are in the works to transport 1.2 million tons of ash from the Dan River Steam Station to a landfill in Virginia and two million tons from the Sutton Plant to a former clay mine in Chatham County. The state's Coal Ash Management Act set a August 2019 deadline to close the plants' ash basins.

"That would not allow us enough time to be able to move all of that ash or to bury all that ash, so we've got to do something in the meantime," said Davis Montgomery, a Duke Energy district manager.

Transporting all of it would not be without risk.

"For instance, by truck,” said Montgomery. “For this amount of coal ash it would take years, and that's a lot of truck traffic on the road. There's a lot of potential for accidents."

Edwards says there's no perfect answer to dealing with coal ash.

"There's no real ideal situation,” she said. “This is the legacy of coal."

Duke Energy says it would begin landfill operations at the Sutton Plant in late 2016, and at the Dan River Steam Station in the first half of 2017.