GRANTSVILLE, Md. (AP) — The Maryland Department of the Environment says the growth of a coal mine near Grantsville is unlikely to threaten two rare aquatic species. The agency is proposing that Maryland Energy Resources be allowed to double the amount of treated mine drainage and stormwater discharged into the Casselman River from the Casselman Coal Mine. The river is believed to harbor two state-endangered species — the Eastern hellbender salamander and the stonecat catfish. The proposed limit of 290,000 gallons per day would apply to the current permit, which expires at the end of September.