During early geotechnical investigations, the proposed Wastewater Treatment Plant (WWTP) site was found to contain a significant volume of unclassified fill, meeting the definition of a closed open dump. Engineers recommended and designed the removal, disposal, and capping of poor subsurface materials, along with engineered upgrades. Wilhelm Construction served as the general contractor. Materials containing trash or deemed “hot” were disposed of, while clean materials were tested and reused on-site as approved by IDEM OLQ. Side slopes were capped to prevent sediment runoff, and a steel piling earth retention system stabilized the roadway to the existing WWTP and Municipal Garage.

As a separate bid project from Phase I, a third-party engineering firm handled planning, design, permitting, bidding, and construction phase services, with Wilhelm Construction as the general contractor. Phase II includes an 8 MGD (24 MGD peak) WWTP with an influent pump station, headworks facility, four-basin sequencing batch reactor, UV disinfection facility, low-profile cascade aerator, aerobic digester, biosolids dewatering facility, septage receiving station, and lab/office facility.