Ameren Missouri plans to close all coal ash ponds but will leave the waste in place

Over the next five years, Ameren Missouri plans to close the ponds it uses to dump the byproduct of its coal-fired power plants. The company has 15 ponds among its four power plants. Ameren closed two out of the nine ponds at the Meramec Energy Center in St. Louis County earlier this year. Coal-fired power plants have traditionally used water to handle coal ash, but recent advances in technology are allowing utilities such as Ameren to use dry systems instead.