The following story by Eric Nalder was published Aug. 30, 2011 by the San Francisco Chronicle.
ASHBURN, VA. — Pacific Gas and Electric Co. has been unable to provide federal investigators with records showing where it got the pipe that exploded in San Bruno, officials said Monday – a failure that has major implications for the company and other pipeline operators nationwide.
One day before the National Transportation Safety Board is to present its conclusions on what caused the San Bruno blast, agency Chairwoman Deborah Hersman expressed frustration about PG&E’s failure over the past year to produce records identifying the origin of the pipe that ruptured at a defective seam weld Sept. 9, killing eight people and destroying 38 homes.
PG&E’s inability to produce the records on the manufacturer of the 1956-vintage section of pipe was “one of the biggest difficulties for our investigators,” Hersman said.
PG&E spokesman Brian Swanson said the company’s search for the birth records on the San Bruno pipe is “still ongoing.”
The company’s failure to produce documentation adds to questions surrounding its management of the line that runs 51 miles from Milpitas, through San Bruno and into San Francisco’s Dogpatch neighborhood.
Litany of problems
First, PG&E’s computerized records about the line showed that it had no seams, and thus no seam welds that needed to be inspected. Then, 10 months into the San Bruno investigation, the company told federal investigators about an apparent leak on a seam weld 9 miles south of the blast site that had been repaired in 1988.
On Sunday, The Chronicle reported that PG&E engineers knew that defective seam welds had been found less than a year before the disaster on a section of pipe about 2 miles north of where the line eventually ruptured.
Under federal law, pipeline operators must examine records about an urban gas line’s characteristics and history to determine all the risks it might face. They must then address the risks with inspections and, if necessary, repairs.
Despite the pipeline’s apparent history of weld problems, and despite the company’s inability to find records showing where the pipe came from, PG&E never checked the line for problem welds.
“How can you apply integrity management without knowing what you had in the ground?” asked Richard Kuprewicz, a pipeline consultant in Redmond, Wash., who has followed the San Bruno investigation.
Pipeline record-keeping problems have become a national issue. About a third of the federal audits done on pipeline operators in the last five years have found deficiencies in record keeping and failures to properly assess multiple risks, records show.
Jeffrey Wiese, head of the federal Office of Pipeline Safety, sent an advisory bulletin to pipeline operators in January asking them to re-examine their records in light of the San Bruno disaster, noting that some have failed to assess risks regarding faulty seam welds.
Royce Don Deaver, a former pipeline industry engineer who has investigated transmission line failures for lawsuit plaintiffs, said he can “guarantee” that key pipeline records are missing on half-century-old transmission lines coast to coast. More than half the nation’s inventory of transmissions is at least 50 years old.
“It’s a very important issue,” Deaver said. “A lot of companies will have missing records here and there. The regulators have not slapped their hands. They’ve been very tolerant.”
The seam weld that ruptured in San Bruno was so obviously faulty it wouldn’t have met industry standards in use at the time the pipe was put in the ground in 1956, Hersman said Monday in a briefing in Ashburn, Va.
The short sections of pipe, known as “pups,” near the explosion site don’t match metallurgic characteristics of other PG&E pipe on the same line, Hersman said.
“We’ve talked about them as mongrels because we don’t know what their pedigree is,” Hersman said. She added that the safety board fears there could be other pups in the PG&E system.
“We have acknowledged that our past operating and record-keeping practices are not what they should have been,” said Swanson, the PG&E spokesman. “What we are doing now is overhauling and transforming our gas operations.”
Asked how the company can be sure that similarly faulty pipe isn’t lurking, Swanson said, “That’s the point of our aggressive plan to inspect our pipeline system (elsewhere) to identify any weaknesses.”
PG&E has promised to run high-pressure water through more than 100 miles of its older pipelines this year, a test designed to detect flawed welds.