Patrick was retained by Midwest Generation (MWG) to perform hydrogeological investigations of the ash ponds at five coal-fired power plant sites in northern and central Illinois. Patrick developed initial investigation plans that included the proposed monitoring well locations and a proposed list of analytes that were approved by the Illinois Environmental Protection Agency (IEPA). Patrick then implemented the initial investigations at each of the sites by installing the required number of monitoring wells, collecting groundwater samples and geological data, and measuring the elevation of the groundwater, the ash ponds, and any nearby surface water bodies. The data collected during the initial investigations was compiled and the results were presented in reports that were submitted to the IEPA, along with long-term groundwater monitoring plans. Midwest Generation also retained Patrick to conduct an investigation into the bottom of three inactive process ponds located at its Will County Station. The purpose of the investigation is to determine the integrity of the pond bottoms and the likelihood that they are hydraulically connected to the nearby Des Plaines River. Patrick conducted the investigation using Patrick-owned boats and sediment sampling equipment. This work was performed by Patrick as part of a much larger effort to assist Midwest Generation in upgrading all of the NPDES Permits for all of their Illinois plants. As part of this larger effort, Patrick conducted numerous impact assessments and feasibility studies involving IEPA required changes regarding management of coal pile runoff and boiler cleaning waste at its facilities.