SAN BRUNO (CBS SF/AP) — The head of a federal safety panel is faulting Pacific Gas & Electric company for a “litany of failures” leading up to last year’s pipeline explosion  in San Bruno that killed eight people and incinerated a suburban neighborhood.

Deborah Hersman, chairman of the National Transportation Safety Board, said Tuesday PG&E also exploited weak safety oversight by state regulators who placed “a blind trust” in the utility.

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The findings in the draft final report, which were publicly discussed for the first time Tuesday by the five-member board, indicate that flawed pipe, operations and oversight led to the disaster.

“It was not a question of if this pipeline would burst, but when,” Hersman said.

KCBS’ Holly Quan Reports:

The explosion sent a giant plume of fire into the air that continued to burn for an hour and a half before PG&E employees were able to shut off the flow of gas. It was the worst pipeline accident in a decade.

The discussion of the draft final report in Washington, D.C., follows 12 months of work by NTSB investigators. The report included metallurgical analyses of the 28-foot section of pipeline that ruptured, interviews with victims, PG&E employees and first responders. Investigators also pored over thousands of pages of documents from PG&E.

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Hersman acknowledged the losses of the people of San Bruno whose “lives were forever changed by this event,” and underscored the need for action to ensure that the “lessons of this tragedy are well-learned and not repeated.”

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Much of what is in the comprehensive report was already known said Carl Weimer, the executive director of the non-profit Pipeline Safety Trust.

“PG&E had bad pipe in the ground that they didn’t know about because they had some really atrocious record-keeping practices,” he said.

Weimar added that incorrect inspection techniques were being used because of those very bad practices.

Hersman gave a list of factors that contributed to the disaster including; the pre-accident events at Milpitas terminal, PG&E’s emergency response, the pipeline failure and the cause of the rupture, inline inspection technology as well as what the maximum allowable pressure should be for pipelines built pre-1970.

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All of these factors played into the explosion of Line 132 under San Bruno’s Glenview neighborhood that killed eight people and destroyed 38 homes.

A PG&E spokesman acknowledges the insufficient past record keeping and said the company is now overhauling its operations. San Bruno’s blast is just one of a record five major pipeline accidents currently under federal investigation.

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