... Sandwich has three public water supply wells that supply drinking water to Sandwich residents. Samples from two of these wells had shown low-level contamination by an industrial solvent called trichloroethylene (TCE). TCE is in a class of chemicals called volatile organic compounds (VOCs). The Illinois Environmental Protection Agency (Illinois EPA) conducted an investigation in August to determine the source of this contamination.

What tasks were completed during the August 2005 study? The Illinois EPA and Parsons Engineering Sciences, Inc. (an Illinois EPA contractor) completed the following tasks during this study: sampled both the treated and the untreated water from all three of the Sandwich public water supply wells; sampled eight private wells in the vicinity of the public water supply wells; sampled three existing groundwater monitoring wells; collected soil and groundwater samples from potential sources of contamination and; measured levels of groundwater in the private wells and monitoring wells to establish the direction of groundwater flow.