In late October, the City’s Public Works Department received a Supplemental Permit from the IEPA for the City’s former landfill. The permit approved a hydrogeologic investigation report defining a groundwater sampling and analysis program. The landfill had many sampling wells that were initially installed during the 1990s for landfill condition analysis. Work was done in 2006-2007 retiring or replacing inoperative wells and defining a target zone to monitor that was lower than the landfill waste.
The hydrogeologic report approved by the October 2012 permit defines a network of six existing wells and one new well for primary sampling on a quarterly basis and allows retention of four secondary wells to be used for twice annual monitoring of water levels and basic groundwater parameters. The report also defines up-gradient and down-gradient wells and defines the statistical method to be used for groundwater test results to develop background values. Approval of the hydrogeologic report is a necessary step in landfill closure activities.