Navigating the Meaning of “Hazardous” in the Regulatory Universe – Part 1

“Hazardous” is a term that has a different definition depending on the regulatory framework one is operating under. Understanding the difference in how the term “hazardous” is used  – and how the regulatory definitions overlap – is crucial for compliance with federal and state environmental laws. This understanding becomes even more critical when considering emerging federal regulations related to per- and polyfluoroalkyl substances (PFAS).

In September 2022, the U.S. Environmental Protection Agency (EPA) issued a proposed rule to designate two PFAS – perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) – as “hazardous substances” under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).  The target date for publication of the final rule is March 2024.  Since the proposed rule was published, EPA is considering designating additional PFAS as hazardous substances under CERCLA. In April 2023, EPA published an Advance Notice of Proposed Rulemaking (ANPRM), seeking input and data on seven additional PFAS, their salts and structural isomers, and/or precursors to PFOA and PFOS, in support of the development of future regulations similar to those proposed for PFOA and PFOS.

Of significance, the proposed regulation would affect any entity that handles PFOA and PFOS, even passive receivers like landfill operators. Anyone considered a potentially responsible party (PRP) under CERCLA –including current and past facility owners/operators, arrangers, and transporters (42 USC 9607) – could be held liable for cleanup costs. Although EPA indicated it would use its enforcement discretion to focus on “PFAS manufacturers and other industries whose actions result in the release of significant amounts of PFAS into the environment,” congressional action would be necessary to provide statutory liability exemptions. Given the ubiquity of PFAS in the environment and consumer products, CERCLA liability for PFAS contamination could have significant financial implications. 

What Is a Hazardous Substance Under CERLCA?

CERCLA gives the federal government broad authority to clean up factories, landfills, and other sites contaminated by hazardous substances. The law’s expansive definition of “hazardous substance” indicates the breadth of this authority. Examining the statute’s regulatory intent may help distinguish the term “hazardous substance” from hazardous waste. Given that PFAS have been manufactured and used in various industries in the U.S. since the 1940s, there is considerable potential for historical PFAS contamination.

From a regulatory policy perspective, CERCLA’s definition of “hazardous substance” first incorporates other definitions of the term included in several other federal statutes:

• Clean Water Act (CWA) section 311 (“CWA Hazardous Substances”)
  • See  40 CFR 116.4  in Table 116.4 A “List of Hazardous Substances” and Table 116.4 B “List of Hazardous Substances by CAS Number”
• CWA section 307(a) (“CWA Toxic Pollutants”)
  • See Toxic Pollutants listed in 40 CFR 401.15, Priority Pollutants listed in Appendix A to Part 423, and Toxic Criteria for states not complying with CWA section 303(c)(2)(B) listed in 40 CFR 131.36
• Clean Air Act (CAA) section 112 (“CAA Hazardous Air Pollutants [HAPs]”)
  • See 42 U.S.C. 7412(b)(1) and 40 CFR Part 63 Subpart C
• Resource Conservation and Recovery Act (RCRA) section 3001 (“RCRA Hazardous Wastes”)
  • The F List (non-specific source wastes) 40 CFR 261.31
  • The K List (source-specific wastes) 40 CFR 261.32
  • The P list and U List (discarded commercial chemical products) 40 CFR 261.33
• Toxic Substances Control Act (TSCA) section 7 (currently no substances are designated under this authority) (42 USC § 9601(14)). EPA may also define, “such elements, compounds, mixtures, solutions, and substances which, when released into the environment may present substantial danger to the public health or welfare or the environment,” as hazardous substances under CERCLA (42 USC § 9602(a)).

The list of CERCLA hazardous substances can be found at 40 CFR 302.4. 

The proposed PFAS rule marks the first time EPA has used CERCLA to identify specific substances as “hazardous.”

The risks for PRPs are particularly acute any time CERCLA rules apply, as multiple parties may be held jointly and severally liable for 100 percent of the cleanup costs at designated sites

(42 USC 9607). Of significance also is the possibility of the final rule being used to reopen previously closed CERCLA projects.

Example: In the context of PFAS, consider that a current or past owner of a facility with PFAS contamination could potentially be held responsible for the total cost of cleanup, even if PFAS contamination occurred decades ago before it owned the facility, and it did not cause or contribute to the contamination. Even if a PRP is not found responsible, it still faces the risks and costs associated with responding to (and possibly litigating) claims. As we know, PFAS cleanup costs are staggering. 

Stay Tuned for  Part 2…