BILLINGS, Mont. — U.S. officials moved Thursday to strengthen safety rules for the nation’s 300,000-mile network of natural gas transmission pipelines in response to numerous fiery accidents, including a 2010 California explosion that killed eight people and injured more than 50.
The Department of Transportation proposal would expand inspection and repair rules to include lines in some rural areas and newly installed lines in burgeoning gas drilling fields.
Pressure-testing for leaks would be required on older lines that were previously exempt, such as the Pacific Gas and Electric Company pipe constructed in 1956 that broke and torched a residential neighborhood in San Bruno, California, six years ago.
But the government is sidestepping for now action on emergency valves that can automatically shut down ruptured gas lines. That issue was highlighted by San Bruno, where a 30-inch-diameter pipeline buried beneath a suburban street continued spewing gas for 95 minutes after it broke, burning 38 homes, before a utility worker manually shut it down.
The Associated Press has reported on the potential benefits of automatic valves, and safety regulators have urged making them mandatory. But the gas industry has resisted, in part due to their potential high cost.
In the past two decades, the government has recorded more than 2,000 accidents on gas transmission lines across the U.S., resulting in 46 deaths, 181 injuries and $1.8 billion in damages.
The AP obtained details on Thursday’s proposal in advance of its public release.
Transportation Secretary Anthony Foxx said it represents “commonsense measures” that are needed to handle a dramatic increase in domestic natural gas production in recent years.
They would bring under federal regulation for the first time roughly 11,000 miles of “gathering lines” that transport fuel directly from the wellhead to storage areas, officials said.
“The significant growth in the nation’s production, usage and commercialization of natural gas is placing unprecedented demands on the nation’s pipeline system,” Foxx said in a statement provided to the AP.
The rules would extend pressure-testing to include lines built before 1970, a step the National Transportation Safety Board has long recommended.
Some companies already have been testing older lines voluntarily, said Marie Therese Dominguez, administrator for the Transportation Department’s Pipeline and Hazardous Materials Safety Administration. But Dominguez said the agency has identified 7,400 miles of pipe that have never been assessed for problems.
“I really do think this is going to lead to a higher level of safety,” she said. “It’s going to reduce the number of incidents related to gas transmission.”
Dominguez said the use of automatic shut-off valves remained a high priority for the agency and would be addressed separately. She could not offer a timeline.