Insights

On September 18, EPA announced that it will prioritize Toxic Substances Control Act (“TSCA”) review for “new chemicals related to data centers and artificial intelligence (“AI”) projects,” in an effort to “streamline permitting and regulations to accelerate American data center development.”

Responding to the D.C. Circuit’s deadline to inform the court how it wishes to proceed in litigation challenging the agency’s listing of two types of per- and polyfluoroalkyl substances (PFAS) as hazardous substances under Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), the Environmental Protection Agency (EPA) stood behind its rule. In a September 17, 2025 filing, EPA told the court that the Trump administration had completed its review and would ultimately keep the Biden-era CERCLA final rule in place. The agency also requested that the court remove—i.e. pause—the abeyance placed on the proceedings, so that the lawsuit could move forward and be adjudicated.

On September 11, 2025, the Environmental Protection Agency (EPA) asked the D.C. Circuit to vacate regulations for four types of polyfluoroalkyls (known collectively as “PFAS”) in drinking water. The motion for partial vacatur marks a significant reversal in the agency’s policy, as the EPA had previously vigorously defended legal challenges to the first-of-their-kind standards in federal court for the past two years. See American Water Works Association, et al. v. EPA, case no. 24-1188 and consolidated cases (D.C. Cir. filed June 7, 2024). Just this month, the case was given the green light to proceed, after being held in abeyance (at the request of both parties) so that the Trump administration could determine how it wished to proceed. The change signals a willingness on the part of the administration to act on previously issued non-legally binding announcements of forthcoming changes to Biden-era rules and may also serve as a harbinger for how the new administration will tackle PFAS under other statutes, such as the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).