Per- and Polyfluoroalkyl Substances (PFAS) in Municipal Wastewater Treatment Facilities

Per- and polyfluoroalkyl substances, or PFAS, are a group of several thousand manmade chemicals that have been used widely in consumer products and industry since the 1940s.  Due to their unique chemical structure, PFAS are extremely stable and repel oil, grease, water, and heat.  Because of their long history of use, scientific studies have shown PFAS are ubiquitous and can have serious adverse impacts on human health and the environment, even at very low levels.

The same properties that make PFAS stable also make them extremely resistant to breaking down in the environment (persistent), giving them the nickname “Forever Chemicals.” PFAS also migrate easily in water and air, and because of their persistence, can travel far from where they were used or released to the environment.


The Connecticut Department of Energy and Environmental Protection (DEEP) contracted with Weston & Sampson Engineers, Inc. to perform a study assessing the potential presence of PFAS in various environmental media at select water pollution control facilities (WPCFs) within Connecticut, as well as in their receiving waters and in downstream aquatic species in such waters.  Thirty-five (35) WPCFs were selected for participation by DEEP to provide geographic coverage of the State and cover a range of differing community sizes, inputs, and treatment processes.

Environmental media tested for PFAS included:

  • Influent, effluent, and sewage sludge from 35 WPCFs, sampled in summer 2021 and winter 2022
  • Composite sewage sludge and incinerator scrubber water from 4 WPCFs that incinerate sewage sludge, sampled in summer 2021 and winter 2022
  • Fish tissue and surface water (upstream and downstream) near 10 WPCF outfalls, sampled in Fall 2021 only.

 The Report

Any questions regarding this report should be directed to Christopher Falk and Jueda Shytko  Any general questions regarding PFAS can be directed to

EPA Monitoring Guidance & DEEP’s next steps

On December 5, 2022, the United States Environmental Protection Agency (EPA) released a memo titled Addressing PFAS Discharges in NPDES Permits and Through the Pretreatment Program and Monitoring Programs, which identifies its efforts and plan to approve PFAS sampling methods for various environmental media and recommends the implementation of quarterly PFAS monitoring at all publicly owned treatment works (POTWs) nationwide in order to assess the presence and concentration of PFAS in the discharges.

In the absence of an approved Clean Water Act test method under 40 CFR 136, the EPA recommends the use of draft analytical method 1633 and analysis for all 40 PFAS parameters that are detectable using that draft method.  The draft analytical method 1621 for adsorbable organic fluorine can be used in conjunction with draft method 1633, if appropriate.  The final, multi-lab validated version of analytical method 1633 is expected to be approved by the EPA by the end of 2023 for all eight environmental matrices (wastewater, surface water, groundwater, soil, biosolids, sediment, landfill leachate, and fish tissue).  Multi-lab validation has not yet taken place for draft analytical method 1621.

The DEEP is planning to implement PFAS monitoring requirements in all WPCF NPDES permits after EPA has approved draft analytical method 1633 and within a timeframe which allows WPCFs adequate time to plan and budget for PFAS sampling.

Further Information

  1. CT DEEP Resources
  2. EPA Resources
  3. PFAS Communications Resources for Municipalities
    • The Water Research Foundation (WRF), in partnership with American Water Works Association, has developed communications materials that utilities and municipalities can use as they interact with customers, regulators, and other stakeholders to communicate clearly about all aspects of PFAS.The materials can be downloaded on WRF’s website for free after making an account. The research paper, can be viewed in the July-September 2022 edition of WRF’s publication Advances in Water Research


For other information, please contact the Municipal Facilities section by e-mail.

Content last updated June 15, 2023