PFAS Compounds

News reports regarding per- and polyfluoroalkyl substances (together abbreviated as PFAS) are showing up all over the state and country as more people become informed about these materials. PFAS compounds are a class of thousands of human-made chemicals used in everything from food packaging and cookware to upholstery, clothing and firefighting foam. The chemicals do not readily break down in the environment, so they are commonly referred to as “forever chemicals”. Since these compounds do not readily break down in the environment, they are commonly found in dust, air, soil and water.

There are currently no state or federal water quality regulations for PFAS compounds. In February, 2022 the State of Wisconsin Natural Resources Board (NRB) voted for water quality standards for drinking water and surface water, while voting against a standard for groundwater. Those recommendations still have to pass through a legislative process to become enforceable standards in the State of Wisconsin.

The drinking water standard recommended by the NRB is 70 parts per trillion (ppt) (also expressed as nanograms per liter or ng/l) for PFOA and PFOS, individually and combined. The surface water standard recommended by the NRB is 8 ppt for PFOS, 22 ppt for PFOA for surface waters that are used as public drinking water supplies, and 95 ppt for all other surface waters.

In 2020, the Wisconsin Department of Natural Resources conducted background testing of surface waters throughout the state in an effort to better understand the impacts throughout the state. More information on this background testing can be found on the Wisconsin DNR PFAS Surface Water Testing webpage.

Background tests were conducted on the Fox River at the Main Street Bridge in Oshkosh and on Lake Winnebago at the outlet in Neenah. The Fox River in Oshkosh had results of 0.856 ppt for PFOS and 0.831 ppt for PFOA. The Lake Winnebago outlet at Neenah had results of 2.17 ppt for PFOS and 1.17 ppt for PFOA.

On December 27, 2021, the United States Environmental Protection Agency published the fifth Unregulated Contaminant Monitoring Rule (UCMR 5). UCMR 5 requires sample collection for 30 chemical contaminants between 2023 and 2025 using analytical methods developed by EPA and consensus organizations. This action provides EPA and other interested parties with scientifically valid data on the national occurrence of these contaminants in drinking water. UCMR 5 requires public water utilities to test for the presence of 29 different PFAS compounds as well as lithium. With UCMR 5 requiring testing starting in 2023, the City of Oshkosh Water Utility is preparing our testing procedures to be able to comply with this rule. More information on the UCMR can be found on the US EPA Unregulated Contaminant Monitoring Rule website.