On March 14, 2023, the US Environmental Protection Agency issued a proposed rule that would establish legally enforceable drinking water standards for six per- and polyfluoroalkyl substances (PFAS). This rule follows the EPA’s October 2021 PFAS Strategic Roadmap, which called for establishing a National Primary Drinking Water Regulation.

PFAS exist in water systems and in the environment throughout the United States. Drinking water standards not only affect public water systems but drive wastewater effluent limitations and remediation standards. Therefore, drinking water standards for PFAS will impact local governments and businesses throughout the country.

What Are PFAS?

Sometimes called “forever chemicals,” PFAS are a group of chemicals that have been widely used in products such as non-stick cookware, water and stain-resistant fabrics, food packaging, and firefighting foams since the 1940s. These chemicals make products water, heat, and stain resistant. PFAS exposure can occur by consuming water or food, inhaling air or dust, or by dermal contact.

Currently no federal regulation or federally-enforceable standard exists for PFAS in the environment. In 2016, EPA published non-enforceable health advisory levels (HALs) for two types of PFAS, and in 2022 updated those HALs to an effective “non-detect” level and to include additional PFAS chemicals. Several states already have implemented regulations to restrict or set standards for PFAS.

EPA’s Proposed Rulemaking

The proposed rule would create a National Primary Drinking Water Regulation for six PFAS: perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), hexafluoropropylene oxide dimer acid (HFPO-DA) and its ammonium salt, perfluorohexane sulfonic acid (PFHxS), perfluorobutane sulfonic acid (PFBS), and mixtures of these PFAS.

The regulation seeks to establish legally-enforceable Maximum Contaminant Levels (MCLs) for these six PFAS in drinking water in the low parts per trillion—often called “non-detect” levels. In addition to enforceable levels, EPA is proposing for two of the six PFAS (PFOA and PFOS) zero Maximum Contaminant Level Goals (MCLGs), defined as “the maximum level of a contaminant in drinking water at which no known or anticipated adverse effect on the health of persons would occur, allowing an adequate margin of safety.”

The proposed rule would require public water systems to monitor for PFAS. Water systems would need to notify the public should PFAS levels exceed the proposed standards. In addition, the water system would have to take immediate steps to remediate the PFAS level to below the MCLs.

Implications of the Proposed Rule

This proposed rule would have significant ramifications on manufacturers that use PFAS in production, PFAS-precursor suppliers, water utilities that operate treatment plants and supply drinking water, businesses that own or operate property on which PFAS may have been released, and federal and state environmental agencies. The costs associated with monitoring and reporting PFAS, on top of the costs associated with implementing approved treatment technologies to meet the new MCLs, are not insignificant, especially for smaller water treatment facilities. As wastewater effluent limitations and site remediation standards are driven by MCLs, the regulation also could affect operational and remedial costs for industrial facilities and contaminated sites.

Looking Ahead

The public comment period for the proposed regulation will run for sixty (60) days following its publication in the Federal Register. EPA will hold a public hearing on May 4, 2023 at which the public can attend and provide verbal comments on the rule proposal. The relevant Docket ID is No. EPA-HQ-OW-2022-0114.

EPA currently anticipates finalizing the regulation by the end of 2023.

Dentons has expertise counseling clients throughout the US and around the globe on regulatory, litigation, and transactional matters involving PFAS and other regulated chemicals.