Board finds PG&E at fault for San Bruno explosion

Decades of mismanagement by the Pacific Gas & Electric Company led to the San Bruno pipeline explosion  — which killed eight people last September — the federal government said Tuesday.

The National Transportation Safety Board reported PG&E failed to properly assess the risk and had installed a bad pipe in the Northern California city. The city of San Bruno was the “victim” and not one of the responsible parties in the explosion, which had also destroyed dozens of houses in the surrounding areas.

“This represents a failure of the entire system — a system of checks and balances that should have prevented this disaster,” Robert L. Sumwalt, an NTSB board member, told the Los Angeles Times. “The seam weld may have been the technical reason, but this was an organizational accident.”

The specific cause of the San Bruno accident was an electrical failure that allowed excess gas to leak into the pipeline, building up pressure and eventually leading to the explosion. But NTSB officials place more blame in PG&E’s lack of internal regulation when building the pipelines decades ago — particularly in the welding structures of the lines.

“There is scant evidence of quality control measures when the pipeline was installed,” Donald Kramer, one of the agency’s investigators, told the Times. “Either the inspections were not done or they were not done properly, and there is no evidence of testing.”

Last September, the natural gas pipeline had exploded suddenly, with the flames spreading rapidly into the neighborhood for about an hour. Residents reported initially believing the eruption was an earthquake.

A spokesman from PG&E has acknowledged the board’s findings and said the company plans to follow its recommendations.