MADISON — The Wisconsin Department of Natural Resources (DNR) announced Nov. 3 the results of a study conducted to understand the extent of per- and polyfluoroalkyl substances (PFAS) contamination in shallow groundwater throughout Wisconsin.  

PFAS are a group of human-made chemicals used for decades in numerous products, including non-stick cookware, fast food wrappers, stain-resistant sprays and certain types of firefighting foam. These contaminants have made their way into the environment in a variety of ways, including spills of PFAS-containing materials, discharges of wastewater that contain PFAS from treatment plants and use of certain types of firefighting foams. 

During the summer and fall of 2022, the DNR used funding from the U.S. Environmental Protection Agency (EPA) to collect water samples from across the state and analyzed them for PFAS. 

In total, 450 samples were collected voluntarily from private wells distributed throughout Wisconsin. Most private wells that were sampled had PFAS concentrations below current Wisconsin Dept. of Health Services’ (DHS) health recommendations, and overall, the number of areas in Wisconsin with significant PFAS contamination were limited. 

The DNR’s groundwater study shows roughly 7 in 10 private wells contain one or more PFAS, but only 1 in 100 contain PFAS above DHS’ current health guidelines. 

The results of the DNR’s groundwater study were released in the Journal of Environmental Science & Technology (ES&T).     

“The information gained through this groundwater study, combined with compliance sampling in public water systems and surface water monitoring efforts, will help us in developing an understanding of where PFAS are found in Wisconsin’s water,” said Steve Elmore, DNR Bureau of Drinking Water and Groundwater Director. “This knowledge will allow us to use our limited resources to address PFAS most efficiently.” 

New drinking water regulations that went into effect in Wisconsin in 2022 require ongoing sampling of public drinking water systems. By the end of 2023, Wisconsin will have PFAS data for nearly all public water systems in the state due to these regulations.  

Private well owners who find their well is impacted by PFAS at levels above DHS’ health recommendations may be eligible for grants through the Well Compensation Grant Program to install a new well or water treatment system. Funding from the federal Bipartisan Infrastructure Law is available to both municipal water systems and wastewater systems that have been impacted by PFAS. 

The DNR is currently working to enact standards for four PFAS compounds (i.e., PFOA, PFOS, PFBS, and HFPO-DA (GenX)) in groundwater. If enacted, standards would help to limit the amount of these compounds that could reach groundwater. This would protect private well owners from PFAS exposure and reduce treatment needs for impacted public water systems that source water from groundwater. 

The public is encouraged to participate in the groundwater standards rulemaking process. More information about this proposed rule and opportunities to participate are available on the DNR’s website and by subscribing to receive email updates.  

Visit the Wisconsin DNR website to learn more about efforts undertaken to mitigate PFAS contamination in Wisconsin, including the PFAS Action Plan.