PHMSA issued this Advance Notice of Proposed Rulemaking on April 28, 2025, and it has been submitted to the Office of the Federal Register for publication. Although PHMSA has taken steps to ensure the accuracy of this version of the Advance Notice of Proposed Rulemaking posted on the PHMSA website, and will post it in the docket (PHMSA-2019-0091) on the Regulations.gov website (www.regulations.gov), it is not the official version. Please refer to the official version in a forthcoming Federal Register publication, which will appear on the websites of each of the Federal Register (www.federalregister.gov) and the Government Printing Office (www.govinfo.gov). After publication in the Federal Register, this unofficial version will be removed from PHMSA’s website and replaced with a link to the official version. PHMSA will also post the official version in the docket.