The U.S. Department of Transportation (DOT) has issued a notice of proposed rulemaking establishing a set of regulations for the shipment of liquefied natural gas (LNG) by rail tanker cars. 

DOT's Pipeline and Hazardous Materials Safety Administration (PHMSA) is making the proposal for public comment in cooperation with the Federal Railroad Administration (FRA), seeking to authorize rail transport of LNG for the first time. In the United States, trucks and ships are the only two forms of bulk transport for liquefied methane. LNG by rail is authorized in Canada.

Efforts have been underway since last year at DOT to develop a framework to transport the fuel by rail. Earlier this year, President Trump issued an executive order to speed up the process.

PHMSA Administrator Skip Elliott called rail transport a "safe, reliable, and durable mode of transportation" for LNG. Elliott called the proposal a "major rule" for which the agency will pay close attention to the upcoming public comment period.

FRA shares oversight with PHMSA.  FRA Administrator Ronald Batory said the rulemaking is "consistent with our systemic approach to accident prevention, mitigation and emergency response." PHMSA's proposed rule acknowledges the risk of LNG rail shipments, but said it plans to take a comprehensive approach that lowers risk to people and the environment.

Currently, FRA can approve LNG being transported by rail if it is contained in a portable tank, and the Hazardous Materials Rule that is now proposed for change does authorize specifications (DOT 113) for a tank car to carry other flammable cryogenic liquids.

"It is specifically designed for the transportation of refrigerated liquefied gases," DOT said in its notice of proposed rulemaking. "The design specification may be similarly suitable for the transport of refrigerated liquid methane [LNG]."

The two federal agencies cited many potential logistical and economic benefits to shipping LNG by rail, including the fact that railroads reach many isolated parts of the nation where pipelines don't go, and the greater safety and efficiency of the rail transport increases U.S. energy competitiveness.

Nearly three years ago, the Association of American Railroads (AAR) submitted a petition to PHMSA, seeking authorization for LNG rail shipments in DOT-113 tank cars. AAR stressed that rail transport was safer than the ongoing truck transportation of the fuel.

Back in early 2017, the Center for Biological Diversity asked PHMSA to deny the AAR petition for the rule change, citing potential environmental impacts. The environmental group argued that PHMSA needs to do an extensive environmental evaluation and prepare an environmental impact statement.

Last Friday, the Sierra Club said the latest proposal "represents a shocking willingness to put workers and families at risk for the benefit of corporate polluters." Dirty Fuels Campaign Director Kelly Martin cited "numerous deadly oil train accidents" in recent years as one reason for not allowing LNG rail transport.

PHMSA said the new rule would reduce the environmental impact of LNG transportation, and that the agency "proposes to make a finding that the proposed amendments” to the Hazardous Materials Rule “would not result in a significant environmental impact."