EPA, in collaboration with the Department of Defense (DoD), announced a new analytical method—Method 1633—to test for PFAS in various environmental media on September 2. This single-laboratory validated method can test for 40 PFAS compounds in wastewater, surface water, groundwater, soil, biosolids, sediment, landfill leachate, and fish tissue using liquid chromatography with tandem mass spectrometry (LC-MS/MS).

While it is a positive sign that EPA and DoD are making this single-laboratory validated method available in terms of testing for PFAS, there are also real concerns about how this will impact the municipal clean water community – especially in the Clean Water Act (CWA) National Pollution Discharge Elimination System (NPDES) permitting context. With this web-published methodology, EPA is giving state regulatory authorities the green light to begin to incorporate this methodology into individual permits and collect PFAS monitoring data.

EPA and DoD released the methodology prior to publishing the single-laboratory validation report, possibly to gather informal feedback. There is no formal public comment period but interested stakeholders can send feedback to EPA’s Engineering and Analysis Division within the Office of Water. EPA and DoD will begin the multi-laboratory validation process in late 2021 (with expected completion in 2022) and then plan to go out for public comment and subsequent CWA 40 CFR Part 136 promulgation – likely in 2023.

NACWA has been anticipating some movement this fall on PFAS analytical methods and the potential for monitoring to end up in NPDES permits, although we did not expect a single-validated method to be ready for incorporation into permits without going through the usual multi-laboratory validation process.

Members may recall the November 2020 EPA Memorandum, Interim Strategy for Per- and Polyfluoroalkyl Substances in Federally Issued National Pollutant Discharge Elimination System Permits, that recommended EPA permit writers consider incorporating phased-in PFAS monitoring and best management practices for wastewater and stormwater discharges likely to contain PFAS. While the memo’s recommendations only applied to federally issued permits, this new methodology gives states additional influence to begin monitoring PFAS in wastewater effluent and biosolids.

As for other pending PFAS methodologies, EPA continues to work on Method 8327 (direct injection) which can test for 24 PFAS compounds and is expected to be released this year, and SW-846 Method 8327 (isotope dilution) which can test for 40 PFAS constituents and is currently in the multi-laboratory validation stage.

NACWA is reviewing Method 1633 and is interested in member feedback on the laboratory details and instructions. Please contact Emily Remmel, NACWA’s Director of Regulatory Affairs with any specific input or comments on this method.