Complying with several executive orders (E.O.), the Department of Transportation (DOT) issued a notice of proposed rulemaking (NPRM) to revise federal hazardous materials regulations (HMR) and remove pages considered “redundant” because they repeat hazardous materials references listed in Environmental Protection Agency (EPA) regulations.

The NPRM says revisions to the HMR are supported by E.O. 12866, ‘‘Regulatory Planning and Review’’ issued by President Bill Clinton; E.O. 13211, “Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use” issued by President George W. Bush; and E.O.s 14154, “Unleashing American Energy”, 14156, “Declaring a National Energy Emergency,” 14192, “Unleashing Prosperity Through Deregulation,” and14219, “Ensuring Lawful Governance and Implementing the President’s ‘Department of Government Efficiency’ Deregulatory Initiative” issued by President Donald Trump.

To fulfill the requirements of those EOs, on July 1, 2025 the DOT’s Pipeline and Hazardous Materials Safety Administration (PHMSA) issued the NPRM—“Hazardous Materials: Remove Redundant List of U.S. EPA CERCLA Hazardous Substances”—that says it seeks to “eliminate redundant and unnecessary requirements in the hazardous materials regulations.”

That includes hazardous materials listed in “Appendix A” of the “List of Hazardous Substances and Reportable Quantities” maintained by the EPA under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), which is a federal statute that addresses the cleanup of hazardous waste sites and provides the federal government with the authority to respond to releases or threatened releases of hazardous substances.

Furthermore, the PHMSA proposes renaming “Appendix B”—the “List of Marine Pollutants,” also maintained by the EPA—to Appendix A, and to revise the definition of ‘‘marine pollutant’’ to refer to Appendix A rather than referring to Appendix B, says the NPRM.

In addition, a list of about 800 hazardous substances ranging from acetaldehyde to zirconium tetrachloride is maintained under CERCLA, and that EPA codified and periodically updates by adding, removing or revising entries, the NPRM says.

Under the current regulations, PHMSA must publish a rulemaking periodically to update the list as a companion action to EPA rulemakings that make changes to the list of CERCLA hazardous substances. However, when that occurs, there “is often a time lag between when EPA updates its list through a rulemaking and when PHMSA issues a corresponding rulemaking.”

During such a delay, “stakeholders have expressed confusion whether a material that is listed by EPA is regulated by PHMSA as a hazardous material,” and “PHMSA also receives similar inquiries when reportable quantities for certain materials are adjusted,” says the NPRM. 

By “removing the separate list of hazardous substances in the HMR, and referencing EPA’s list of hazardous substances,” stakeholders will be provided with “more regulatory certainty,” according to the NPRM, which also says, the proposed revisions to the HMR will “satisfy the intent of the CERCLA statute and improve clarity while also improving efficiency.”

The deadline to file comments with PHMSA on the NPRM is on or before Sept. 2, 2025, and all submissions must include the Docket ID No. PHMSA–2025–0093. Comments can be sent by the following methods:

Federal eRulemaking Portal: https://www.regulations.gov. Follow the online instructions for submitting comments.

Mail: Docket Management System: U.S. DOT, 1200 New Jersey Avenue SE, West Building Ground Floor, Room W12–140, Washington, D.C. 20590–0001. Those submitting comments by mail need to submit two copies of their comments, and if they wish to receive confirmation that PHMSA received those comments, a self-addressed stamped postcard needs to be included.

Hand Delivery: U.S. DOT Docket Management System, West Building Ground Floor, Room W12–140, 1200 New Jersey Ave., SE, between 9 a.m. and 5 p.m., Monday through Friday, except federal holidays.

Fax the comment to 202–493–2251. Please include the docket number PHMSA–2025–0093 at the beginning of faxed comments.

Comments received may be posted without change to https://www.regulations.gov, including any personal information provided. For further information, contact Yul B. Baker Jr., Transportation Regulations Specialist, 1200 New Jersey Ave., SE, Washington, D.C. 20590; or by calling 202–366–8553; or by sending an email to yul.baker@dot.gov.