On March 10, 2020, the US Environmental Protection Agency (EPA) published its proposed Preliminary Regulatory Determinations for perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in drinking water, thereby taking the initial steps to formally regulate two of the most common chemicals in the family of compounds known as per- and polyfluoroalkyl substances (PFAS) in drinking water. EPA will seek comment on these preliminary determinations until May 11, 2020.
This announcement represents EPA’s preliminary determination that PFOA and PFOS meet the statutory criteria for regulation under the Safe Drinking Water Act and is the beginning of the regulatory process. After reviewing comments, EPA will make a final regulatory determination—positive or negative—on PFOA and PFOS. If EPA makes a positive determination, it must publish a proposed Maximum Contaminant Level Goal (MCLG) (a non-enforceable reference goals) and proposed National Primary Drinking Water Regulation (NPDWR) (the actual enforceable standards) within 24 months. After the proposal, the agency must publish a final MCLG and promulgate a final NPDWR within 18 months (with a possible 9-month extension). Therefore, if the preliminary Regulatory Determination being introduced here is adopted as final, this will start the clock on that process.
However, EPA could still decide to make a negative determination (i.e., decide not to regulate PFAS) after reviewing comments; the notice states that EPA can withdraw its determination to regulate based on new information. A decision not to regulate is a final agency action that is subject to judicial review. EPA can also decide to make no final regulatory determination at this time.
Here are some other key points about today’s announcement:
- EPA’s preliminary determination is based on an HRL (Health Reference Level) of 70 ppt total combined concentration of PFOA and PFOS. This is the same as EPA’s current lifetime Health Advisory, which is non-enforceable. This suggests that the current 70 ppt Health Advisory level would be the most likely basis for an MCLG and NPDWR if EPA makes a positive determination.
- EPA relied on occurrence data primarily sourced from UCMR 3 sampling between 2013 and 2015. The median summed PFOA/PFOS concentration was 50 ppt. 1.37% of samples had detections of either or both compounds, and the summed concentrations exceeded the 70 ppt level at a minimum of 1.3% of public water systems (63 public water systems serving 5.6 million people, located in 25 states, tribal areas or territories). EPA also supplemented its UCMR data with data from states that have sampled for PFAS, including New Hampshire, Colorado, Michigan, and New Jersey. EPA noted that it is aware that additional states have conducted monitoring and specifically stated that it will consider any additional data submitted in response to its proposal to inform its regulatory decision. It also intends to include nationwide drinking water monitoring for PFAS in UCMR 5 (to be conducted in 2023-25).
- EPA signaled that it is seeking comment on treatment technologies for PFOA/PFOS, including cost analysis and effectiveness.
EPA solicited comments on all aspects of its regulatory determination, including whether there is additional data it should consider, whether it has appropriately considered the data that it currently has, and most pertinently, on potential regulatory constructs and monitoring requirements it may consider if it moves forward with a positive determination. It is also seeking comment on potential regulatory approaches for additional PFAS chemicals (i.e., how to evaluate other PFAS chemicals for regulation – individually, in groups, or based on available treatment technologies).
EPA’s announcement also includes negative determinations for five other chemicals and a decision not to make a regulatory determination for three chemicals (including 1,4-dioxane, another emerging contaminant). Those determinations will likely be overshadowed by the preliminary positive determinations for PFOA and PFOS.
EPA also published an update to its PFAS Action Plan on February 26, 2020. The update summarizes EPA’s upcoming actions on PFAS, including the proposed regulatory determination published today. This summary includes the following activities that may lead to further regulations for wastewater treatment facilities and water utilities:
- EPA is developing a risk assessment for potential public health and ecological risks associated with PFOA and PFOS in land-applied biosolids;
- EPA is conducting a multi-industry study to determine which industries are most likely to discharge PFAS into the environment, including information about PFAS in discharges to surface waters from industrial sources that may be subject to future regulation, and included analyses of industrial sources and discharges of PFAS in its Preliminary Effluent Guidelines Plan 14;
- EPA is considering the development of water quality criteria for PFAS, by considering whether it has enough data to support the development of water quality criteria and scoping the development of draft human health and aquatic life criteria for PFOA and PFOS.