Read the full article by Letitia Moore, Holland & Knight LLP (JDSupra)

“California continues to develop tools for evaluating per- and polfluoroalkyl substances (PFAS) at cleanup sites. In May 2020, the San Francisco Bay Regional Water Quality Control Board issued an ‘Interim Final Environmental Screening Levels (ESLs) for Per- and Polfluoroalkyl Substances (PFAS): Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoate (PFOA)’ Memorandum setting groundwater and soil ESLs addressing direct exposure, ecotoxicity and ingestion risk levels for PFOS and PFOA. The PFAS ESLs are part of the ongoing effort by the San Francisco Regional Water Board to “provide conservative screening levels … to help expedite the identification and evaluation of potential environmental concerns at contaminated sites.”1

The Interim Final PFAS ESLs Memorandum identifies:

  • soil ESLs for 1) terrestrial habitat, 2) leaching to groundwater and 3) direct exposure human health risk
  • groundwater ESLs for 1) aquatic habitat ecotoxicity, 2) seafood ingestion and 3) direct exposure human health risk

For groundwater direct exposure ESLs, the Regional Water Board selected 1.7E-03 microgram per liter (µg/L) (PFOS) and 5.4E-04 µg/L (PFOA). The ESLs are delineated as guidance and not mandatory, but the Regional Water Board will require technical analysis to justify use of alternative screening levels…”