Last month (October 2024), EPA published final recommended aquatic life criteria and benchmarks for various per- and polyfluoroalkyl substances (“PFAS”). For two of the more well known PFAS substances, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), EPA published final recommended freshwater criteria as well as saltwater benchmarks. For eight other PFAS compounds that were described as “data-limited”, only freshwater benchmarks were published.
EPA noted that this effort reflects the latest scientific knowledge regarding the effects of PFAS on water quality and was part of the agency’s PFAS Strategic Roadmap. The criteria and benchmarks are intended to protect aquatic organisms such as fish and aquatic insects. EPA’s final recommendation concludes that concentrations of PFAS above the announced benchmarks or criteria have the potential to harm or kill aquatic organisms. Acute criteria (aimed at protecting aquatic species from short-term high PFAS concentrations) as well as chronic criteria (designed to protect these species from long-term or repeated exposure to a PFAS substance) were announced.
These recommended criteria and benchmarks are not regulatory limits and do not automatically become part of a State’s water quality standards. However, states may use EPA’s final recommended criteria and benchmarks as a basis for adopting future state water quality standards that would become regulatory in nature.
Acute and Chronic Freshwater Criteria for PFOA and PFOS
For PFOA and PFOS, acute and chronic criteria were published that are meant to support aquatic life in freshwater. These final recommended freshwater criteria are summarized in the following table published by the EPA:
Acute Saltwater Benchmarks for PFOA and PFOS
Due to data limitations, the EPA only published acute saltwater benchmarks for PFOA and PFOS. The benchmarks represent the maximum concentrations of PFOA and PFOS in saltwater that the EPA expects can support the protection of aquatic life from acute effects. As reflected in the following table published by EPA, the benchmark for PFOA is 7.0 mg/L and the benchmark for PFOA is 0.55 mg/L. Both of the benchmarks are for a one-hour average that is not to be exceeded more than once in three years on average.
Acute Freshwater Benchmarks for Eight Additional PFAS
EPA developed acute freshwater benchmarks for the eight additional data-limited PFAS. For each of these substances, the benchmark is for a one-hour average that is not to be exceeded more than once in three years on average. As with the other criteria, these benchmarks were also published by EPA in the below table.
1) perfluorobutanoic acid (PFBA) à 5.3 mg/L
2) perfluorohexanoic acid (PFHxA) à 4.8 mg/L
3) perfluorononanoic acid (PFNA) à 0.65 mg/L
4) perfluorodecanoic acid (PFDA) à 0.50 mg/L
5) perfluorobutanesulfonic acid (PFBS) à 5.0 mg/L
6) perfluorohexanesulfonic acid (PFHxS) à 0.21 mg/L
7) hexadecafluoro-2-decenoic acid (8:2 FTUCA) à 0.037 mg/L
8) pentadecafluorodecanoic acid (7:3 FTCA) à 0.012 mg/L
Published Criteria’s Impact on State Water Quality Permitting
The criteria do not automatically become part of state water quality standards, but many states will likely use them as a basis.
According to EPA, the recommended criteria and benchmarks are not regulatory, and do not automatically become part of a State’s water quality standards. Although states can establish water quality criteria based on EPA’s recommended criteria, any established criteria by a state is not legally effective under the Clean Water Act until the criteria are officially adopted into the State’s water quality standards and approved by EPA. States will be able to use EPA’s recommended criteria and benchmarks for PFAS as a basis when adopting future water quality standards.
Individual state statutes may require rulemaking before implementing the criteria.
Although these announced recommended criteria will likely be used by states as a basis for future water quality permit criteria, individual state statutes may require formal rulemaking for the criteria to be implemented into state water quality permits.
For example, although the Wisconsin Department of Natural Resources has the legal authority to issue WPDES permits pursuant to the Department’s delegated authority under the Clean Water Act, “the department shall promulgate by rule effluent limitations…” (Wis. Stat. 283.11 (1)). In addition to the criteria not being “regulatory” in nature, the wording of individual state statutes may prevent these recommended criteria from being automatically implemented into state water quality permits.
Expect Future Guidance from EPA
EPA Plans to release more guidance regarding implementation of the recommended criteria.
While developing these recommended criteria, EPA received and responded to public comments that expressed concern over how the criteria would be implemented. EPA’s summary of implementation-related comments included: requests for implementation guidance, requests that EPA work with states to develop implementation guidance documents, and requests that EPA provide guidance on currently available treatment options for PFAS. EPA further noted that several public comments expressed concern that releasing criteria before any implementation guidance is provided may lead to overly restrictive permit limits.
EPA responded to these implementation-related concerns by stating that the agency “intends to develop separate implementation materials in the future to provide additional information related to the 2024 Final PFOA and PFOS Aquatic Life Criteria and Benchmark documents”. EPA noted that the development of implementation guidance will include opportunities for states and tribes to collaborate and provide input.
PFAS Regulatory Impacts to Your Business
Michael Best’s team of environmental regulatory lawyers have been tracking EPA’s PFAS initiatives and how federal PFAS developments impact state-regulatory matters for years. We have significant experience counseling clients on PFAS regulatory matters, including risk analysis and mitigation strategies. If you have any questions or concerns about how EPA’s criteria and benchmarks may impact your facility, please contact your Michael Best attorney, or any of the authors below.