PFAS Sampling

Sun Prairie Utilities is Participating in a Voluntary PFAS Sampling Program

Sun Prairie Utilities takes pride in providing high-quality, safe drinking water that meets regulatory standards. Wisconsin and states nationwide face challenges related to identifying and managing Per- and Polyfluoroalkyl substances (PFAS) in their water supplies. PFAS compounds have been manufactured for use in everyday items such as nonstick cookware, water-resistant clothing, and personal care products and have been widely used in firefighting foams, in industrial applications, and at military installations. Currently, there is no federal regulation governing PFAS. Still, the EPA and the Wisconsin DNR have made preliminary recommendations and are conducting research to determine the appropriate standards for municipal water supplies.  

What are the concerns about PFAS?

There are up to 5,000 chemicals that are classified as PFAS. Studies have examined possible relationships between levels of PFAS in blood and harmful health effects in people. PFAS persist in the environment and the human body for long periods of time. Recent findings indicate that exposure to certain PFAS may have harmful health effects in people related to health complications like cancers, thyroid problems, heart issues, and reproductive issues like infertility, low birth weight, and developmental delays.

What is the Voluntary PFAS Sampling Program?

The Wisconsin Department of Natural Resources (WI DNR) is conducting a voluntary statewide investigation into the occurrence of Per- and Polyfluoroalkyl Substances (PFAS) in drinking water at municipal drinking water suppliers in WI during 2022.  Sun Prairie Utilities chose to participate in this voluntary sampling for PFAS to proactively assess the potential impacts of PFAS in the area drinking water and to quickly take steps to protect the health of our customers if needed.  

What is the EPA’s Health Advisory Level and what does it mean?

The Environmental Protection Agency recently set new Interim Health Advisory Levels for two PFAS compounds. Perfluorooctanoic acid (PFOA) levels were set at 0.004 parts per trillion and Perfluorooctane Sulfonate (PFOS) levels were set at 0.02 parts per trillion. These are microscopic levels, and trace amounts of contaminants equivalent to about 1 drop in 500,000 barrels of water. These new health advisories are also below the current reliable detection abilities of scientific equipment (Scientists can currently detect PFAS compounds at 2 parts per trillion.)

What are the PFAS levels in Sun Prairie’s Drinking water?

Sun Prairie Utilities submitted samples in June 2022 to the DNR voluntary sampling program from all active well locations in the city of Sun Prairie. These samples were sent to the State Laboratory of Hygiene to be tested for 18 PFAS compounds. All samples tested below recommended levels set by the Wisconsin Department of Health Services, in fact, in 124 of the 126 tests conducted no PFAS were detected (zero/or at levels below test sensitivity.)

Well 4 (Bird Street and Athletic Way)

Unit of measure
  Sample DHS Advisory EPA Sample DHS Advisory EPA
ug/L .00131 .04 n/a .00102 450 .002
ng/L 1.31 40 n/a 1.02 450,000 2
ppt 1,310 40,000 n/a 1,020 450,000,000 2,000





Water sample results from all Sun Prairie Utilities well sites can be reviewed on the WI DNR site at

Resources for More Information

Wisconsin DNR PFAS Information Page

Wisconsin DNR Voluntary Drinking Water PFAS Sampling Project for Municipal Systems

Wisconsin PFAS Action Plan

EPA Drinking Water Health Advisories for PFOA and PFOS