Comment submitted by AxNano Inc.

PFAS Treatment and Destruction Technology Providers Oppose Withdrawal of PFAS Drinking Water Standards To: U.S. Environmental Protection Agency Docket ID: EPA-HQ-OW-2025-1742 Subject: Opposition to Proposed Delay of PFAS Drinking Water Standards for PFOA and PFOS and Proposed Withdrawal of Standards for PFHxS, GenX, PFNA, and Hazard Index Dear Administrator Zeldin, We, the undersigned PFAS treatment and destruction system suppliers, write to express our strong opposition to the EPA’s proposed rules to delay implementation of the drinking water standards for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) as well as rescind the drinking water standards for perfluorohexanesulfonic acid (PFHxS), perfluorononanoic acid (PFNA), hexafluoropropylene oxide dimer acid (GenX), and the Hazard Index for mixtures of these PFAS chemicals, including PFBS. These standards are essential not only for protecting public health but also for sustaining the momentum of innovation and investment in PFAS treatment technologies. Rolling back or delaying these standards would undermine the significant progress already made. Over the past several years, our industry has responded to the urgent need for PFAS mitigation by developing and scaling up advanced treatment and destruction systems. As deployment has increased, costs have begun to decline—a trend that is expected to continue with regulatory certainty and market stability. Weakening the regulatory framework now would reverse that trajectory. It would slow the adoption of proven technologies, increase per-unit costs, and reduce incentives for continued innovation. Moreover, the proposed withdrawal threatens the business case for expanding PFAS treatment and destruction capacity. Our companies have made substantial investments in research, infrastructure, and workforce development based on the expectation of a consistent national regulatory framework. Removing or delaying these standards would create uncertainty, discourage further investment, and delay the delivery of effective solutions to communities in need. We urge the EPA to maintain the drinking water standards for PFHxS, PFNA, GenX, and the Hazard Index and to maintain the timeline for enforcing drinking water standards for PFOA and PFOS. A strong, science-based regulatory foundation is critical to ensuring that the technologies necessary to address PFAS contamination remain viable, scalable, and accessible to all. Sincerely, M. Douglas Speight II Chief Executive Officer, AxNano Doug.speight@axnano.com