Interesting article here: PG&E says it is not to blame for San Bruno blast. This is a media report based on a PG&E submission to the NTSB. I haven’t yet found the submission itself among the 40o San Bruno documents listed in semi-random order on the NTSB website, so my comments are based only on the SF Examiner’s interpretation of what PG&E said.
PG&E blame a defective seam weld in the pipe that failed and hence its (unknown?) manufacturer way back in 1954. At face value that attitude is a serious worry. One can only hope that saying “it wasn’t our fault” reflects legal advice and not the real attitude of PG&E management and technical safety people.
To put this in perspective: What if Qantas had said that the manufacturing problem which caused the Airbus 380 engine explosion “wasn’t our fault” (which is true, it was a manufacturer’s defect) and then took no action to check all Airbus 380 engines?
If PG&E were paying attention they would have been aware of the possibility that the pipeline did not meet modern standards. There is enough information around to indicate that there were no records of hydrostatic test for that section of pipeline, that hydrostatic testing was not normal practice in the 1950s, and that the pipe was not seamless as they had thought.
But getting back to the underlying management attitude: There is extensive literature on “High Reliability Organisations” (HROs) such as airlines (pipeline operating organisations should also be included, but whether they really are HROs is an open question). HROs have very few serious failures despite operations that appear to present high risk. There are a number of defining characteristics for HROs but key are an overall “mindfulness” about danger and a preoccupation with the possibility of failure. It’s part of the overall culture of the organisation.
The statements from PG&E don’t demonstrate that they have a culture of mindfulness. Until they do they will continue to be a worry.