NTSB to hold hearing on San Bruno pipeline explosion

Posted on: February 28th, 2011 by Eartha Jane Melzer No Comments

This week the National Transportation Safety Board will hold an uncommon three-day public fact-finding hearing on the Pacific Gas & Electric pipeline explosion that killed eight and burned dozens of homes in San Bruno, Calif., last September.

The San Bruno explosion followed a million gallon Enbridge oil pipeline spill in Michigan and focused attention on the nation’s aging pipeline system, the under-resourced federal regulators charged with oversight and the industry-friendly arrangements that allow the oil and gas industry to write its own regulations on matters such as welding, monitoring and testing pipeline pressure.

The hearing, which begins Tuesday, will look at both the San Bruno incident and safety issues with the nation’s pipeline system as a whole.

NTSB’s preliminary report on the San Bruno incident indicates that a 30-inch diameter steel natural gas pipeline segment installed in 1956 ruptured when an electrical problem increased the gas pressure in the pipe. Approximately 47.6 million standard cubic feet (MMSCF) of natural gas was released and caused an explosion that left a crater 72 feet long and 26 feet wide. The fire destroyed 37 homes and damaged 18 more. Eight people were killed and many more were injured and evacuated.

Investigators say it took PG&E about an hour and a half to access and manually close the mainline valves near the ruptured segments and about four more hours to stop the gas flow to residences at damaged houses.

Though PG&E records stated that the pipeline in the area of the rupture was constructed of seamless pipe, investigators found that the section that had ruptured was seam-welded pipe: some of the seams were welded from both the inside and the outside of the pipe, but others were only welded from the outside.

In January, NTSB issued several “urgent” safety recommendations to PG&E, and state and federal regulators directing them, to verify the makeup of pipelines and the way in which their maximum pressure was determined.

“If companies are basing operating pressures on inadequate or erroneous information contained in their records, safety may be compromised,” NTSB Chairman Deborah Hersman said. “We believe this safety-critical issue needs to be examined carefully to ensure that operators are accurately gauging their risk and that pipelines are being operated at pressures no higher than that for which they were built to withstand.”

At this week’s hearing, NTSB officials are expected to release 4,700 pages of documents from their investigation of the San Bruno incident and PG&E officials are expected to face questions on whether their other pipelines can withstand pressure increases and why they failed to spot welding defects before burying the pipeline.

Bills to increase the number of inspectors at the U.S. Dept. of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMSA), require companies to install automatic shut-off valves on pipelines and set new standards for safety testing of pipelines have been introduced in both the U.S. House and Senate but face a dim future in a Congress where environmental safety rules are under attack.

Some states have decided not to wait on federal action.

Earlier this month, California State Sen. Leland Yee (D-San Francisco) introduced a bill (PDF) to require gas utilities to install remote controlled shut-off valves throughout the state’s pipeline system and concentrate them in areas of seismic activity or high population.
In Pennsylvania the legislature is expected to take action this week on a bill that would put the state in charge of natural gas pipeline safety inspections.

A gas pipeline explosion in Allentown earlier this month killed five people just weeks after a deadly pipeline explosion in Philadelphia. The state, which is experiencing a boom in natural gas development, is also experiencing rapid expansion of pipelines.

“Last year alone 100 billion cubic feet of natural gas was harnessed out of three counties alone in the northern tier of Pennsylvania,” said Rep. Matt Baker (R-Bradford/Tioga). “As you can imagine these gas pipelines are growing exponentially, they are ubiquitous. It’s happening so fast and so frequently that we need to do something immediately to ensure proper pipeline gas safety.”
Carl Weimer, executive director of the non-profit advocacy group Pipeline Safety Trust, said there is a serious need for citizen involvement in Pennsylvania. In an editorial to the Allentown Morning Call, he wrote:

Old pipelines like the one that failed in Allentown are certainly a huge issue, but Pennsylvania also sits dead center in the middle of one of the largest natural gas booms in the world. All that drilling will spawn hundreds of miles of new and higher-pressure pipelines. With so much money to be made from these activities, who but the public can also speak up for safety?
There is probably no place in the nation that needs a strong coalition of voices focused on pipeline safety as much as Pennsylvania does.

In Michigan, a package of bills aimed at strengthening pipeline safety rules, including a measure to assess pipeline impact fees to fund emergency preparedness, failed to clear committee last year and have not been reintroduced.

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