Water Resources Research Act Program

Details for Project ID 2003WI47B

Arsenic Contamination in Groundwater in Southeast Wisconsin

Institute: Wisconsin
Year Established: 2003 Start Date: 2003-03-01 End Date: 2004-02-29
Total Federal Funds: $57,256 Total Non-Federal Funds: $50,906

Principal Investigators: Jean Bahr, Madeline Gotkowitz

Project Summary: Moderate to high levels of arsenic contamination occur in groundwater throughout eastern Wisconsin. Previous studies have shown that oxidative dissolution of arsenic-bearing sulfide minerals is the likely mechanism controlling high levels of arsenic contamination in the Fox River valley area. Our preliminary work indicates that geologic and hydrogeologic conditions contributing to arsenic-impacted wells in southeast Wisconsin differ from those in the Fox River valley. Thus, geochemical mechanisms of arsenic release other than sulfide oxidation, such as the reduction of arsenic-bearing iron- (hydr)oxides, may affect groundwater supplies in southeast Wisconsin. We propose to use groundwater chemistry data, lithologic, mineralogic, and well construction information to identify geologic sources of arsenic. Bench-scale leaching experiments and geochemical modeling will be used to examine the mechanisms controlling the release of arsenic to the ground water. The objectives of this proposed study are to identify the geologic source(s) of arsenic and the geochemical mechanism(s) and environmental conditions that cause release of arsenic to well water in southeast Wisconsin.