A natural gas industry official labeled last fall’s deadly San Bruno pipeline blast as “an anomaly.” Members of the National Transportation Safety Board challenged that assessment.
The last day of the National Transportation Safety Board hearing was supposed to focus on the effectiveness of remote shut-off valves and technologies that can detect pipeline problems.
But what caught the attention of NTSB investigator Bob Trainor was a comment from Christina Sames of the American Gas Association. Sames said the likely cause of the San Bruno blast – a manufacturing defect in the pipe – made the incident “an anomaly.”
The NTSB's Trainor was skeptical; he recalled a Mississippi explosion caused by a problem pipe. "Within the last five years, we’ve had two accidents that have claimed 10 lives," he said. "I question whether these two accidents should be considered anomalies."
Sames replied, "You’re talking about two incidents out of hundreds. To me, that is still an anomaly."
It took an hour-and-a-half to turn off the gas that fueled the San Bruno fire. Sames said installing remote cutoff valves in heavily populated areas across the country could cost $13 billion.
She added that it can be a logistical challenge as well. "If you are trying to install one of these valves in an urban environment, you might not be able to put it above ground. If you put it below ground, you have to have the real estate." That means finding a 30-foot space under a city in which water, sewer and electrical lines may already run underground.