Pipeline in Calif. explosion sprang leak in 1988

Updated at 3:17 p.m. ET

SAN BRUNO, Calif. - Nearly nine months after federal investigators began probing a deadly pipeline explosion near San Francisco, a California utility quietly revealed its ruptured line had sprung a leak in a spot a few miles away years before, a top safety official said Wednesday.

National Transportation Safety Board Chair Deborah Hersman called Pacific Gas & Electric Co.'s recent disclosure of the 1988 gas leak "troubling" before she announced three new safety recommendations at a news conference in San Bruno.

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"If it took them months to realize they had a leak on the same line just nine miles south of the rupture site and only now we're hearing about it, that's very troubling," Hersman said. "They clearly weren't contemplating this information when they were assessing the risk on this line."

Learning about past problems so long after the investigation began hampers federal investigators' ability to quickly determine what caused the fatal blast, she said. Hersman added that the recent disclosure shows that PG&E's record-keeping is inadequate.

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U.S. Rep. Jackie Speier, D-San Mateo, said at the news conference that the recent revelation of the earlier leak raises concern about PG&E's record.

"I'm very dismayed to find that at this late date, PG&E is providing NTSB with what is critical information," she said. "There is a part of me that feels that this area that had the leak should be excavated."

Company spokeswoman Brittany Chord did not immediately respond to an email Wednesday seeking comment.

The board is still probing what caused the Sept. 9 explosion, which sparked a gigantic fireball that engulfed a San Bruno neighborhood and killed eight, injured dozens and destroyed 38 homes.

Hersman said one of the recommendations will press the company to set up new procedures so emergency responders are immediately and directly notified when a possible pipeline rupture occurs.

She also planned to ask the Pipeline and Hazardous Materials Safety Administration, which enforces federal rules for the safe operation of interstate pipelines, to urge pipeline operators nationwide to improve emergency communications plans and share more information about their systems with first responders in local communities.

Hersman is touring the San Bruno neighborhood torched in the blast and is meeting with families who lost relatives in the explosion. She also will meet with local officials and PG&E executives.