Associated Press: Regulators in a handful of Appalachian states that let coal companies inject slurry into abandoned mines say they’re confident the practice is safe, but an Associated Press survey shows they lack scientific data to answer citizens who believe aquifers, water wells and their own health are at risk. None of the five states contacted by AP has studied the chemical composition of slurry, a byproduct left when clay, sulfur and other impurities are removed from coal to make it burn more …