March/April 2022 Issue

Also in this issue: Wisconsin Legislature Initiates Unclaimed Property Voluntary Disclosure Agreements     |     It’s a Good Time to Consider Community Broadband

Enforceable State PFOS/PFOA Drinking Water Standards Likely This Year

Lawrie J. Kobza | 03.20.22

Wisconsin drinking water standards for two kinds of PFAS (perfluoroalkyl and polyfluoroalkyl substances) are likely to become effective later this year. PFAS are a large group of widely used, long lasting chemicals, components of which break down very slowly over time. They are widely used to make various types of everyday products. Because of their widespread use and their persistence in the environment, many PFAS are found in the blood of people and animals all over the world and are present at low levels in a variety of food products and in the environment. Scientific studies have shown that exposure to some PFAS in the environment may be linked to harmful health effects in humans and animals.

Since Spring 2019, the Wisconsin Department of Natural Resources (DNR) has been working on proposed regulations for two kinds of PFAS — perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). PFOA and PFOS are the most well-studied PFAS. They were manufactured for a long time but are no longer manufactured in the United States.

In February 2022, DNR submitted its proposed PFOA/PFOS rules to the Natural Resources Board (NRB) for approval. After heated discussion, the NRB:

• did not approve the proposed groundwater rule, which would have set a PFOA/PFOS groundwater standard of 20 parts per trillion (ppt) separately or combined; 
• approved the surface water rule, which focused on source reduction instead of treatment and which set a PFOS standard of 8 ppt and a PFOA standard of 20 ppt in waters classified as public water supplies and 95 ppt for other surface waters; and 
• modified the drinking water rule to set the PFOA/PFOS standard at 70 ppt (which is the current EPA health advisory level for PFOA/PFOS) instead of at the DNR recommended 20 ppt level.

The two PFAS rules that have been approved now move on to the Legislature for passive review. It is possible that legislative committees could slow down or object to the adoption of these rules. But if they do not, it is possible that the PFOA/PFOS drinking water and surface water rules could become effective as early as June 1, 2022.

The drinking water rule would require all community and non-transient non-community public water systems (e.g. a school system) to test for PFOA and PFOS quarterly, at least initially. The testing requirement for a public water system that serves a population of 50,000 or more would begin on the 4th month beginning after the rule is published. For a public water system that serves a population of 10,000 to 49,999, the testing requirement would begin on the 7th month beginning after the rule is published. And, for a system that serves less than 10,000, the testing requirement would begin on the 10th month after the rule is published. A system must initially take 4 consecutive quarterly samples for PFOA and PFOS. A system may ask the DNR to waive the last 2 quarters of testing if prior levels are below detection.

Once Wisconsin’s 70 ppt PFOS/PFOA drinking water standard becomes effective, it will likely stay in effect until EPA establishes a federal PFOS/PFOA standard. EPA has indicated that it intends to issue a proposed PFOA/PFOS regulation in Fall 2022 and a final regulation in Fall 2023. All expectations are that it will be significantly lower than 70 ppt.