SAN FRANCISCO (Reuters) - The California site of a deadly gas pipeline explosion earlier this month was not on a "top 100" watch list of pipelines monitored by Pacific Gas and Electric, utility executives said on Monday.
The September 9 explosion of a 30-inch steel pipeline ripped through the San Francisco suburb of San Bruno, killing four people, destroying 37 homes and causing hundreds to evacuate.
Homes at the center of the blast were burned to the ground and the disaster has triggered several investigations and widespread concern about the safety of pipelines that crisscross California.
Pipeline around Stanford University and the Silicon Valley hub of San Jose made it to the "top 100" list of pipeline segments, but only two of 47 projects were in construction phase and one more completed.
Most were being monitored for events such as corrosion and the effects of nearby seismic activity.
The utility owned by PG&E Corp released the list of sites after a request from the state's utility commission, which in a statement emphasized that the list was not of pipelines that are at risk or dangerous.
PG&E said customers could call a toll-free number to see if their houses were near the top 100 sites, but executives offered no guidance of what to do with the information or what it meant that the San Bruno site was not on the list.
"We don't know yet what the cause was" of the blast, Pacific Gas and Electric Co. President Chris Johns told reporters. "We were not aware of anything in this particular area that would have met the criteria that would have put it on the list."
Any sites in immediate danger would have been fixed immediately rather than be put on the list, he said, leaving reporters asking whether releasing the list might simply scare customers.
"We understand why you might consider it that way. What we're trying to do is help people understand, to give them insight into it," Johns said.
(Reporting by Peter Henderson; Editing by Eric Walsh)