What are California monitoring regulations on PFOA, PFOS, PFBS, and PFHxS?

In August 2019, the Division of Drinking Water (DDW) set the customer Notification Level of 5.1 parts per trillion (ppt) for PFOA and 6.5 ppt for PFOS and in February 2020, set new a Response Level of 10 ppt for PFOA and 40 ppt for PFOS. In March 2021, DDW issued the notification level and response level for PFBS of 500 ppt and 5000 ppt, respectively.  In October 2022, DDW issued the notification level and response level for PFHxS at 3 ppt and 20 ppt, respectively.

A notification level is a nonregulatory, precautionary health-based measure for concentrations of chemicals in drinking water that warrant notification and further monitoring and assessment.

A response level is a nonregulatory, precautionary health-based measure that is set higher than a notification level and represents a recommended level that water systems consider taking a water source out of service or provide treatment if available to them.

In March 2019, the California State Water Resources Control Board (State Board) began a state-wide PFAS investigation and issued orders to approximately 200 water utilities throughout California to test groundwater wells that are in close proximity to fire training/fire response sites (e.g., airfields), industrial sites, landfills, and/or wastewater treatment plants for PFAS. Since ACWD groundwater sources are not located in close proximity to potential sources of contamination, ACWD was not issued orders to monitor for PFOA, PFOS, or PFBS by DDW.  

Assembly Bill 756 that took effect on January 1, 2020, authorized the State Board to more broadly order water systems to monitor for PFAS and report their detections. ACWD was not issued an order under the Assembly Bill.

In October 2022, DDW issued monitoring orders to numerous water agencies, including ACWD, to monitor all groundwater sources effective January 1, 2023.  The provisions of the Order are similar to the voluntary monitoring program that ACWD began in June 2020.  ACWD will continue to monitor sources on a quarterly basis.


Show All Answers

1. What are PFAS? Per – and Polyfluoroalkyl Substances (PFAS)
2. What are the sources of PFAS?
3. What are the health effects from PFAS?
4. What are California monitoring regulations on PFOA, PFOS, PFBS, and PFHxS?
5. Has ACWD tested its water for PFOA, PFOS, PFBS, or PFHxS?
6. How were tests conducted?
7. How often will ACWD monitor for PFAS?
8. What is ACWD doing about treatment for PFAS?
9. How will customers be updated about future testing results?
10. Where can I find more information?