Groundwater quality at the Saline Valley Conservancy District well field, Gallatin County, Illinois

The Saline Valley Conservancy District (SVCD) operates wells that supply water to most of the water users in Saline and Gallatin Counties, Illinois. The SVCD wells draw water from a shallow sand and gravel aquifer located in close proximity to an abandoned underground coal mine, several abandoned oil wells, and at least one operational oil well. The aquifer that yields water to the SVCD wells overlies the New Albany Shale, which may be subjected to shale-gas exploration by use of hydraulic fracturing. The SVCD has sought technical assistance from the U.S. Geological Survey to characterize baseline water quality at the SVCD well field so that future changes in water quality (if any) and the cause of those changes (including mine leachate and hydraulic fracturing) can be identified.