State Water Board Adopts Lower Response Levels for PFOA and PFOS
Last week, the State Water Resources Control Board’s Division of Drinking Water announced the lowering of response levels for two Per- and Polyfluoroalkyl Substances (PFAS). The updated response levels are 10 parts per trillion (ppt) for perfluorooctanoic acid (PFOA) and 40 ppt for perfluorooctane sulfonic acid (PFOS) based on a running four-quarter average. These response levels supersede those adopted in August of 2019. The current notification levels remain unchanged.

Consistent with Assembly Bill 756, which took effect earlier this year, a series of reporting and notification requirements apply to detections of PFAS in drinking water, and exceedances of the adopted response level will require water systems to either take a water source out of use, treat the water delivered, or provide public notification. This was an anticipated next step in the process of further regulating PFAS in California’s drinking water sources, with the development of a public health goal (PHG) and anticipated action on maximum contaminant levels likely forthcoming. CASA continues to track these developments and is working with agencies and stakeholders to analyze the science underlying these notification and response levels as well as the potential impacts to wastewater agencies.

Do not hesitate to reach out to CASA staff for additional PFAS related information. PFAS biosolids questions should be directed to Greg Kester, and water-related PFAS questions should be directed to Jared Voskuhl.