Plans to build a new, $50-million facility to recycle fly ash in southern Maryland for Atlanta-based Mirant could fall through if the Environmental Protection Agency designates the coal combustion by-product as a hazardous waste, says Mirant’s Misty Allen , the utility’s director of external affairs. Photo: The Sefa Group The proposed recycling facility would use a new technology that burns 100% of carbon from coal ash. Allen says Mirant filed an application on March 26 with the Maryland Public Service Commission to build a facility in Morgantown, Md., that would recycle up to 400,000 tons of coal ash per year.
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.