Duke Energy is planning to remove all of its coal ash from pits at a South Carolina plant that environmentalists say Duke Energy Says It Will Close SC Coal Ash Pits GREENVILLE, S.C. - Duke Energy is planning to remove all of its coal ash from pits at a South Carolina plant that environmentalists say Check out this story on WLTX.com: http://on.wltx.com/1ALRSDI GREENVILLE, S.C. - Duke Energy is planning to remove all of its coal ash from pits at a South Carolina plant that environmentalists say threatens the Saluda River.