EPA Announces National Regulation for PFAS by ACWA Staff Apr 10, 2024 Water News The U.S. Environmental Protection Agency has announced a new national maximum contaminant level (MCL) of 4.0 parts per trillion (ppt) for PFOA and PFOS as individual contaminants and a standard of 10 ppt for three other chemicals — PFNA, PFHxs, and HFPO-DA (commonly referred to as GenXChemicals). In addition, EPA will utilize a hazard index to regulate mixtures of PFHxS, PFNA, HFPO-DC and PFBS. This enforceable rule requires public water systems to monitor for these PFAS, notify the public of the levels of these PFAS and reduce the levels of these PFAS in drinking water if they exceed the MCL. Utilities will have five years to come into compliance with the rule. ACWA previously supported EPA’s efforts to address PFAS contamination and protect public health through setting drinking water standards that are based on sound science and robust analysis. Unfortunately, the MCL is not feasible because the anticipated costs of complying are not adequately captured under EPA’s cost assessment. In a separate effort, the California Office of Environmental Health and Hazard Assessment on April 5 adopted and published public health goals of 0.007 ppt for PFOA and 1.0 ppt for PFOS. A public health goal is a drinking water objective that does not pose a significant risk to health and is not an enforceable standard. The State Water Resources Control Board listed developing a PFAS MCL as a 2024 Drinking Water Priority.
