Broader natural gas transmission pipeline safety regulations are in the proposal stage that would add new assessment and repair criteria, and include lines in medium population density areas, called moderate consequence areas, where an incident would pose a risk to human life.
The proposed regulations provide pipeline operators with regulatory certainty, and respond to congressional mandates and outside safety recommendations, the Department of Transportation’s Pipeline & Hazardous Materials Safety Administration (PHMSA) released the proposed rule March 17.
Specifically, they address four congressional mandates from the 2011 Pipeline Safety Reauthorization law, one Government Accountability Office recommendation, and six National Transportation Safety Board recommendations, including one adopted following the Sept. 9, 2010, gas pipeline rupture and explosion in San Bruno, Calif., which killed eight people.
PMSA said pipelines built before 1970 are currently exempt from certain pipeline safety regulations because they were constructed and placed into operation before such requirements ended up developed, PHMSA officials said.
In its investigation of the PG&E gas pipeline failure and explosion, NTSB concluded hydrostatic testing of grandfathered pipelines would have likely exposed the defective pipe that led to the San Bruno pipeline’s failure, PHMSA said.
“Following significant pipeline incidents such as the 2010 San Bruno, Calif., tragedy, there was a pressing need to enhance public safety and the integrity of the nation’s pipeline system,” PHMSA Administrator Marie Therese Dominguez said. “The proposal’s components address the emerging needs of America’s gas pipeline system, and adapt and expand risk-based safety practices to pipelines located in areas where incidents could have serious consequences.”
Comments on the proposed rule are welcome for 60 days following its publication in the Federal Registered, which should occur shortly.
PHMSA said the proposed changes also are expected to reduce pipelines’ methane and other greenhouse gas emissions by lowering the number of incidents. The rule also would change the way pipeline operators secure and inspect gas transmission pipeline systems following extreme weather events, such as hurricanes and flooding.
It also would:
• Modify repair criteria for pipelines inside and outside of high-consequence areas.
• Provide additional direction on how to evaluate internal inspection results to identify anomalies.
• Clarify requirements for conducting risk assessment for integrity management, including addressing seismic risk.
• Expand mandatory data collection and integration requirements for integrity management, including data validation and seismicity.
• Require additional post-construction quality inspections to address coating integrity and cathodic protection issues.
• Require new safety features for pipeline launchers and receivers.
• Require a systematic approach to verify a pipeline’s maximum allowable operating pressure (MAOP) and requiring operators to report MAOP exceedances.