The pipeline explosion in San Bruno that killed eight people and destroyed dozens of homes last September is the focus of a three day hearing beginning Tuesday in Washington, D.C.
First up to testify were PG&E pipeline engineers. The questioning centered around what happened after the initial explosion. Gas continued to feed a pillar of fire for an hour and a half before workers could manually shutoff the flow.
Officials at PG&E acknowledged they rejected installing valves that could have automatically shut off or remotely controlled the flow of gas in event of an accident.
National Transportation Safety Board investigators questioned the employees about a company memo that said installing the valves would have "little or no effect on increasing human safety or protecting properties."
Chih-hung Lee, author of the memo, said he considered only industry studies, not government studies, in reaching his conclusions.
Investigators pointed to a 1999 Transportation Department study that warned there is a significant safety risk as long as gas was being supplied to the rupture site and operators lacked the ability to quickly close manual valves.
"Any fire would have greater intensity and would have greater potential for damaging surrounding infrastructure if it is constantly replenished with gas,'' the government study said. "The degree of disruption in heavily populated and commercial areas would be in direct proportion to the duration of the fire."
Coroner's reports indicate at least five of the people killed in San Bruno were trying to flee when they died.
PG&E also released new documents in the investigation. You can find those here.
"The hearing is an important opportunity for the city to represent the interests of our community, especially the victims," Jackson said in an e-mail. "We want to assure that their voice is not lost in what will be a highly technical discussion and analysis."
The goal of the hearing is "to gather additional facts and information to supplement the record," NTSB spokesman Peter Knudsen said.
A cause is not expected to be named until six more months.
Bay City News contributed to this report.