Previous construction work near Line 132 could have been a factor in triggering the Sept. 9 pipeline explosion in the Crestmoor neighborhood, an independent panel of experts concluded in a report released today.
The findings from the five-member panel, appointed by the California Public Utilities Commission after the fire, don't point to a root cause of the blast. The National Transportation Safety Board is still working through that task as part of its ongoing investigation into the pipeline's failure.
However, the panel's report blasted PG&E's technical competence and pipeline integrity management procedures and said the accident was a direct result of multiple shortcomings in PG&E's oversight of the safety of its gas transmission system.
"I think our overarching conclusion is that quality assurance has to be an integral part of a continuing process of quality management, and we didn't see that," panelist Paula Rosput Reynolds told the CPUC today.
She and the other four members of the panel found that PG&E's pipeline integrity management program had focused more on worker safety than the safety of the system.
The company's data management, organizational effectiveness, and resource allocation also came under fire, as did its response to the Crestmoor disaster, the five-stage "Pipeline 2020" improvement program.
"Pipeline 2020 is not a plan," Reynolds said, calling the materials "reactive" and underdeveloped.
Lee Cox, PG&E Corp.'s interim CEO, said the company welcomed the panel's report and agreed with the report's finding that PG&E and the CPUC need to work more closely together on pipeline safety.
"It’s clear, as we’ve openly acknowledged, that we need to make major improvements in our operations and culture in order to deliver the performance our customers rightly expect—and that we expect from ourselves," Cox said in a statement.
Although the NTSB is responsible for identifying the root causes of the explosion, the panel's report pointed to the sewer work the city had done in 2008 near the explosion site as a likely trigger for the accident. Consultants hired by the panel determined that the pipe bursting procedure used for the sewer pipe replacement likely eroded the strength of the longitudinal seam weld where the gas transmission line ruptured.
The independent panel also found that it could not separate technical incompetence from the problems it identified with PG&E's safety record, according to the report.
Reynolds said PG&E's staff is committed and has good technical skills, but that they are under-trained and too generalist. The company is also understaffed, the panel found.
"Only one senior person was an engineer, and did not have much gas experience," panelist Karl Pister told the CPUC.
He said the company did not have a solid grasp on systems engineering, which is necessary for construction, evaluation and maintenance of gas transmission lines.
As a result, the company has been focused on "cataloguing information" instead of collecting useful data that can be used to make inferences about the pipelines, Pister said.
He said widespread hydrostatic pressure testing of pipelines, which PG&E has vowed to do in the wake of the explosion, is not as valuable as doing more in-depth testing—such as metallurgic testing in addition to hydrostatic—on smaller sections of pipeline.
The report also called out the CPUC's oversight of the company, concluding that the agency didn't have enough resources to properly monitor PG&E's performance.
The panel also said changes needed to be made to the CPUC's culture, which serves as an impediment to effective regulation because, as a result of state budget constraints, its staff isn't able to keep with up changing technology and regulations.
Bay City News Service contributed to this story.