The U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration (PHMSA) has announced proposed regulations to update critical safety requirements for natural gas transmission pipelines.
In the past twenty years, the government has recorded more than 2,000 accidents on gas transmission lines across the United States, resulting in 46 deaths, 181 injuries and $1.8 billion in damages.
The DOT's proposal includes new assessment and repair criteria for gas transmission pipelines and will expand those criteria to include areas referred to as Moderate Consequence Areas (MCAs) that have medium population density and where a gas line accident would put human life at risk.
"This proposal includes a number of commonsense measures that will better ensure the safety of communities living alongside pipeline infrastructure and protect our environment," said U.S. Transportation Secretary Anthony Foxx.
The top safety measure in the new rule is the inclusion of pipelines built before 1970. Until now, pre-1970 pipelines have been exempt from testing and certain pipeline safety regulations. After the 2010 natural gas explosion in San Bruno, California where 8 people died and more than 50 were injured, the National Transportation Safety Board concluded that hydrostatic testing of grandfathered pipelines would have likely exposed the defective pipe that led to the pipeline failure.
"Following significant pipeline incidents such as the 2010 San Bruno, California tragedy, there was a pressing need to enhance public safety and the integrity of the nation's pipeline system," said PHMSA Administrator Marie Therese Dominguez. "The proposal's components address the emerging needs of America's natural gas pipeline system and adapt and expand risk-based safety practices to pipelines located in areas where incidents could have serious consequences."
The proposed changes provide pipeline operators with regulatory certainty that they need when making decisions and investments to improve gas transmission infrastructure, and address priorities outlined as part of the Climate Action Plan to reduce methane emissions. The proposed changes to gas transmission safety regulations are expected to result in fewer incidents, which could lead to a reduction in gas released into the atmosphere as greenhouse gases (GHG). The proposed rule is expected to result in net annual average reductions of 900-1,500 metric tons of carbon dioxide and 4,600-8,100 metric tons of methane, a powerful greenhouse gas.
The rule also proposes changes to the way that pipeline operators secure and inspect gas transmission pipeline infrastructure following extreme weather events, such as hurricanes and flooding.
In addition to the specific requirements mentioned above, the rulemaking proposal would revise and strengthen federal Pipeline Safety Regulations by:
- Modifying repair criteria for pipelines inside and outside of high consequence areas
- Providing additional direction on how to evaluate internal inspection results to identify anomalies
- Clarifying requirements for conducting risk assessment for integrity management, including addressing seismic risk
- Expanding mandatory data collection and integration requirements for integrity management, including data validation and seismicity
- Requiring additional post-construction quality inspections to address coating integrity and cathodic protection issues
- Requiring new safety features for pipeline launchers and receivers
Requiring a systematic approach to verify a pipeline's maximum allowable operating pressure (MAOP) and requiring operators to report MAOP exceedances.
Not included in the proposal are required emergency valves that can automatically shut down ruptured gas lines.