State Attorneys General File Amicus Brief Defending EPA’s PFAS Drinking Water Rule

On January 17, seventeen states and the District of Columbia filed an Amicus Brief in the U.S. Court of Appeals for the D.C. Circuit defending EPA’s National Primary Drinking Water Regulation (NPDWR (rule)) for six PFAS. The Amicus Brief states that the PFAS rule supports the states’, “interests in protecting their residents from the harms of PFAS exposure through drinking water.” The Brief also says that the EPA rule provides important public health protections for states that do not have existing PFAS regulations and complements and reinforces existing state approaches and rules by establishing a federal floor.

The states filing the briefing oppose the reasoning of the utility and industry groups that filed the petitions for lawsuits against EPA for the final PFAS rule and request they be denied. The states’ arguments for supporting EPA’s rule and opposing the petitions include:

  • The Rule serves the public health mandate of the Safe Drinking Water Act (SDWA) by regulating contaminants of concern with substantial evidence of toxicity and advances its Cooperative Federalism framework that gives primacy enforcement authority to states for implementing the rule.
  • The states support EPA’s regulatory determination for both individual and mixtures of PFAS because they are likely to occur in public water systems with a frequency and at levels of public health concern.
  • The rule’s hazard index approach is an appropriate and reasonable regulatory tool to evaluate and mitigate the harms of co-occurring contaminants across a variety of environmental media, including from PFAS in drinking water.
  • Petitioners misconstrue the SDWA language procedural requirements with respect to finalizing the regulation in parallel with a regulatory determination and erroneously conflating cost with feasibility in EPA’s economic analysis.

For more information, read the Amicus Brief here.