Three environmental groups want the N.C. Administrative Hearings Office to overturn permits state regulators issued for using coal ash from Duke Energy as structural fill at former clay mines in Lee and Chatham counties. The N.C. Department of Environment and Natural Resources issued the permits June 5 to Green Meadow LLC and its parent, Charah Inc. They allow coal ash from Duke Energy plants around the Carolinas to be used in mine reclamation projects at the Colon Mine in Lee County and the Brickhaven Mine in Chatham County.