Why is the Environmental Protection Agency (EPA) updating PFAS standards? What is the new threshold for PFAS? How does it compare to the old threshold? When does Sweetwater Authority need to comply?

Prolonged exposure to high levels of PFAS is believed to result in negative health effects including links to liver damage, immune system impacts and certain cancers. The EPA has tightened its regulations in response to the latest understanding of the potential harm from these chemicals.

The new EPA maximum contaminant level for PFOA and PFOS, two types of PFAS, is 4 parts per trillion (ppt), which is equivalent to one drop of water in five Olympic-sized swimming pools. This is a significant reduction from the previous combined Health Advisory threshold of 70 ppt (PFOA + PFOS).

The EPA also set the maximum contaminant level for PFHxS, PFNA, and HFPO-DA (GenX) at 10 ppt. Additionally, the EPA set the maximum contaminant level for a combination of PFHxS, PFNA, PFBS, and HFPO-DA as a hazard index of 1. The formula for the hazard index is below where [x] denotes concentration of x . None of these PFAS had prior thresholds.

You can click here to be directed to the EPA website for more information about what the agency has done over the years to track PFAS.

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1. What is Sweetwater Authority doing to comply with the new EPA standards? Does Sweetwater Authority need to conduct additional testing?
2. Why is the Environmental Protection Agency (EPA) updating PFAS standards? What is the new threshold for PFAS? How does it compare to the old threshold? When does Sweetwater Authority need to comply?
3. What were the most recent testing results? Why would there be a fluctuation between the testing results? Why didn’t Sweetwater Authority detect this sooner?
4. What is the difference between California’s notification level and the response level?
5. Does a changing federal administration affect these regulations? Would federal funding cuts impact PFAS treatment efforts?
6. Have other water agencies started this testing yet? Does Sweetwater Authority collaborate with other water agencies to share testing methods and best practices?
7. Would California set standards that are lower than the EPA standards?
8. If Sweetwater isn’t able to comply with the future EPA standards, what are the impacts?