Acid Mine Drainage (AMD) is currently the main pollutant of surface water in the mid-Atlantic region. AMD is caused when water flows over or through sulfur-bearing materials forming solutions of net acidity. AMD comes mainly from abandoned coal mines and currently active mining. AMD degrades more than 4,500 stream miles in the mid-Atlantic region with the loss of aquatic life, and restricts stream use for recreation, public drinking water and industrial water supplies.
