A survey released by state environmental officials on Friday found that nearly three-quarters of water samples drawn from hundreds of private wells across Wisconsin last year were contaminated with PFAS chemicals, according to the Associated Press.
The Department of Natural Resources, UW–Stevens Point, and the state hygiene laboratory conducted the survey in the summer and fall of 2022. They sampled 450 private wells that reached no deeper than 40 feet at homes across the state.
The U.S. Environmental Protection Agency funded the survey. The study marks the state’s first attempt to sample shallow groundwater away from major municipalities or PFAS cleanup and investigation sites.
The survey revealed that 71% of the samples contained at least one PFAS chemical. About 99% of the contaminated samples had PFAS levels below the state health department’s recommended groundwater limits. About 96% of the contaminated samples contained PFAS levels below limits that the EPA is considering adopting.
Agricultural areas had the highest overall concentrations of PFAS.
Sources of contamination could include PFAS in precipitation, septic systems, and biosolids, which are organic materials recovered from sewage and spread on agricultural land as fertilizer.
Municipalities across Wisconsin are facing PFAS contamination in groundwater, including Marinette, Madison, Wausau, and the town of Campbell on French Island. The waters of Green Bay also are contaminated.
The DNR last year adopted limits on PFAS in surface and drinking water and is currently working on limits in groundwater.
