Modern longwall coal mines can have major impacts on clean water. When coal comes out of the mine, it must be washed. Coal slurry is the mixture of coal refuse, chemicals and water generated at the processing plant when coal is separated from rock. Coal slurry is laden with metals and salts, and it is usually stored on site in massive slurry impoundments. Often coal ash is incorporated into these refuse disposal areas. Without proper treatment and strict management practices, these pollutants can contaminate surface streams and groundwater.
The surface facilities for the Deer Run Mine are located within the city limits of Hillsboro, Illinois. The main outfall will discharge into a tributary of Shoal Creek that flows from the mine site, and then into town behind Hillsboro High School and by Central Park before winding around to the south.
We are especially concerned about mine pollution impacting residents. During high rainfall events, Central Park Creek jumps its banks.Â If the mine ever exceeds pollution limits (which is not uncommon at coal mines in Illinois), these polluted waters would flow directly past the High School and through Central Park where children play.
Additionally, lower reaches of Shoal Creek are rated highly for the quality of the biological communities they support by the Illinois Department of Natural Resources, and we are concerned that mine discharges will negatively impact these habitats.
Subsidence Damage to Aquifers and Streams
Residents of southwestern Pennsylvania have seen the kind of damage that longwall mining induced subsidence can do to hydrological systems. Shallow aquifers may be emptied, leaving rural residents without well water. Streambeds may run dry and even shatter as the ground beneath them drops and fractures. According to the Illinois Environmental Protection Agency, a large percentage of Illinois’ streams are already polluted or unhealthy – longwall mining underneath streams will only make the situation worse.