EPA Proposes to Modify the Definition of Hazardous Waste and Add Multiple PFAS as Hazardous Constituents

The U.S. Environmental Protection Agency (EPA) announced on February 1, 2024, two proposed rules that will add to its comprehensive approach to tackling per- and polyfluoroalkyl substances (PFAS) pollution and the commercial bottom line for hundreds of businesses facing costs for cleanup. The first proposed rule would modify the definition of hazardous waste as it applies to cleanups at permitted hazardous waste facilities. EPA states that this modification “would assure that EPA’s regulations clearly reflect EPA’s and authorized states’ authority to require cleanup of the full range of substances that the Resource Conservation and Recovery Act (RCRA) intended, including emerging chemicals of concern, such as PFAS, that may present substantial hazards, at permitted facilities.” The second proposed rule would amend the RCRA regulations to add multiple PFAS compounds as hazardous constituents. According to EPA, these PFAS “would be added to the list of substances identified for consideration in facility assessments and, where necessary, further investigation and cleanup through the corrective action process at hazardous waste treatment, storage and disposal facilities [TSDF].” EPA will publish the proposed rules “in the next few weeks.”

As reported in our October 29, 2021, blog item, then New Mexico Governor Michelle Lujan Grisham (D) petitioned EPA in 2021 to address PFAS under RCRA. In its response to the petition, EPA outlined plans to initiate the rulemaking process for two rulemakings. These proposed rules constitute initiation of those rulemakings.

Definition of Hazardous Waste Applicable to Corrective Action from Solid Waste Management Units

EPA has created a web page on its “Proposal to Clarify Authority to Address Releases of Hazardous Waste at Treatment, Storage, and Disposal Facilities.” According to EPA, the proposed rule would amend the definition of hazardous waste as it applies to corrective action to address releases from solid waste management units at permitted hazardous waste TSDFs. EPA states that the proposed rule would provide clear regulatory authority to implement fully EPA’s statutory authority “to require corrective action to address releases not only of substances identified as hazardous waste in the regulations but of any substance that meets the statutory definition of hazardous waste.” Publication of the proposed rule in the Federal Register will begin a 30-day comment period. EPA has posted a prepublication version of the proposed rule.

EPA states in the proposed rule that “[w]hile this proposed rule would not directly address PFAS, it would facilitate the use of RCRA corrective action authority to address emerging contaminants such as PFAS, as well as other non-regulatory hazardous waste, at RCRA permitted treatment, storage, and disposal facilities.” According to EPA, the proposed rule would amend the regulations applicable to RCRA TSDFs in two related respects. First, it would amend the definition of hazardous waste applicable to corrective action. EPA states that the proposed rule would amend the definition in Section 260.10 to apply expressly the RCRA Section 1004(5) statutory definition of hazardous waste to corrective action requirements under Section 264.101 and 40 C.F.R. Part 264 Subpart S. Similarly, the proposed rule would amend the identical definition in the hazardous waste facility permitting regulations, Section 270.2, to apply expressly the statutory definition of hazardous waste to the requirements relating to corrective action in Section 270.14(d). EPA notes that these proposed revisions would more clearly provide it the authority to address, through corrective action for solid waste management units, “releases of the full universe of substances that the statute intended — not only hazardous waste and hazardous constituents listed or identified in the regulations, but all substances that meet the definition of hazardous waste in RCRA section 1004(5) at a facility.”

Second, the proposed rule would add RCRA Sections 3004(u) and (v) and 3008(h) to the statutory authorities identified in 40 C.F.R. Section 261.1(b)(2). EPA states that this section “provides that the statutory definitions of solid and hazardous waste govern the scope of EPA’s authority under certain sections of RCRA, not the more limited” 40 C.F.R. Part 261 regulatory definitions. These revisions provide notice of and codify the Agency’s interpretation of the statute — that it provides EPA the authority to address releases from solid waste management units of all substances that meet the definition of hazardous waste under the statute.

Listing of Specific PFAS as Hazardous Constituents

EPA has created a web page on its “Proposal to List Nine Per- and Polyfluoroalkyl Compounds as Resource Conservation and Recovery Act Hazardous Constituents.” According to EPA, the proposed rule would add nine particular PFAS, their salts, and their structural isomers to its list of hazardous constituents in 40 C.F.R. Part 261, Appendix VIII. EPA states that it evaluated the toxicity and epidemiology data for these chemicals and determined that these nine PFAS compounds meet the criteria for listing as RCRA hazardous constituents. EPA notes that the change “would facilitate additional corrective action to address releases of these specific PFAS at RCRA hazardous waste [TSDFs]. It would not require the suite of cradle to grave management controls that are associated with a RCRA hazardous waste.” Publication of the proposed rule in the Federal Register will begin a 60-day comment period. EPA has posted a prepublication version of the proposed rule.

The proposed rule would amend EPA’s regulations under RCRA by listing the following nine PFAS (names given for acid forms below), their salts, and their structural isomers as hazardous constituents in 40 C.F.R. Part 261 Appendix VIII:

• Perfluorooctanoic acid (PFOA; Chemical Abstracts Service Registry Number^® (CAS RN^®) 335-67-1). PFOA is an eight-carbon molecule with seven fully fluorinated carbon atoms and one carboxylic acid functional group. It has been used as a processing aid to produce fluoropolymers and has been found in cleaning agents, waxes, aqueous film-forming foam (AFFF), and other products;

• Perfluorooctanesulfonic acid (PFOS; CAS RN 1763-23-1). PFOS is a fully fluorinated eight-carbon molecule with one sulfonic acid functional group. It has been used in AFFF, in surface treatments of textiles to provide oil and water resistance, in metal plating, and other uses and industries;

• Perfluorobutanesulfonic acid (PFBS; CAS RN 375-73-5). PFBS is a fully fluorinated four-carbon molecule with one sulfonic acid group. It has been used as a replacement for PFOS and has been used in the manufacture of paints and cleaning agents, metal plating, AFFF, to provide oil and water resistance, and other uses and industries;

• Hexafluoropropylene oxide-dimer acid (HFPO-DA or GenX; CAS RN 13252-13-6). HFPO-DA is a six-carbon molecule consisting of five fully fluorinated carbon atoms, one ether functional group, and one carboxylic acid functional group. HFPO-DA is a chemical associated with GenX processing aid technology used to make fluoropolymers without the use of PFOA;

• Perfluorononanoic acid (PFNA; CAS RN 375-95-1). PFNA is a nine-carbon molecule with eight fully fluorinated carbon atoms and one carboxylic acid functional group. It has been used as a processing aid to produce fluoropolymers and has been used or found in metal plating, cleaning agents, waxes, AFFF, energetic materials, and other products;

• Perfluorohexanesulfonic acid (PFHxS; CAS RN 355-46-4). PFHxS is a fully fluorinated six-carbon molecule with one sulfonic acid functional group. It has been used in AFFF, in surface treatments of textiles to provide oil and water resistance, in metal plating, and other uses and industries;

• Perfluorodecanoic acid (PFDA; CAS RN 335-76-2). PFDA is a ten-carbon molecule with nine fully fluorinated carbon atoms and a carboxylic acid functional group. It has been used as a processing aid to produce fluoropolymers and has been used or found in metal plating solutions, cleaning agents, waxes, AFFF, and other products;

• Perfluorohexanoic acid (PFHxA; CAS RN 307-24-4). PFHxA is a six-carbon molecule with five fully fluorinated carbon atoms and a carboxylic acid functional group. It has been used or found in metal plating solutions, cleaning agents, waxes, AFFF, and other products; and

• Perfluorobutanoic acid (PFBA; CAS RN 375-22-4). PFBA is a four-carbon molecule with three fully fluorinated carbon atoms and one carboxylic acid functional group. It has been used or found in metal plating, cleaning agents, waxes, AFFF, energetic materials, and other products.

According to the proposed rule, entities potentially affected by this action include hazardous waste TSDFs with solid waste management units (SWMU) that have released or could release any of the PFAS proposed to be listed as RCRA hazardous constituents. EPA states that it has identified 1,740 such facilities that could be subject to additional corrective action requirements (pursuant to RCRA Section 3004(u) and (v)) to address releases not already subject to corrective action pursuant to EPA’s corrective action regulations. The proposed rule includes a list of North American Industrial Classification System (NAICS) codes that EPA intends to be a guide for stakeholders to determine whether this action may affect them. For each listed NAICS code, EPA provides the number of facilities and the number of facilities with a higher likelihood of handling PFAS.

Commentary

EPA’s actions here are entirely consistent with its well-communicated goal of using its authority under all environmental statutes EPA implements to address PFAS contamination. These actions reflect the next logical use of EPA’s authority under RCRA to compel the cleanup of PFAS contamination. Some may argue these are small steps that are limited in scope, but these initiatives reflect an Agency laser-focused on using whatever authority it can find to address PFAS contamination. These rules also telegraph a sobering message to business entities with PFAS waste issues that cleanup costs may be in their future.