San Bruno Evacuees Must Wait to Return

Last Updated 8:47 p.m. ET

Residents of a neighborhood devastated by a thunderous pipeline explosion and inferno likely won't be allowed to move back into their homes Saturday, a local official said.

After authorities toured the damaged area, San Bruno Mayor Jim Ruane said some residents were being allowed back into a limited section to retrieve some belongings. But he said he "doubts" that any will be able to return permanently to their homes Saturday.

"We're being very cautious," Ruane said.

Meanwhile, CBS Station KPIX 5 in San Francisco reports that the American Red Cross is encouraging financial donations instead of food and clothing to assist people displaced by Thursday's fire in San Bruno.

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Calif. Sen. Barbara Boxer, National Transportation Safety Board Vice Chairman Christopher Hart, Lt. Gov. Abel Maldonado and other local officials toured the burned-out homes, some of which are left with only a chimney standing.

Boxer says the group saw remnants of melted cars in driveways as well as a portion of the ruptured pipeline.

"It's a heartbreaker when you see that huge piece of pipeline that just blew up from the rest of the pipeline," she said.

The White House said that President Obama called California Gov. Arnold Schwarzenegger today to express his condolences for the loss of life in San Bruno, and his concern for those still recovering from injuries and picking up the pieces of their lives.

Officials were still trying to determine what led up to the blast that killed at least four people, injured dozens of others and raised questions about the safety of similar lines that crisscross towns across America.

At least 50 people were hurt, with seven suffering critical injuries in the explosion Thursday evening that left a giant crater and laid waste to dozens of 1960s-era homes in the hills overlooking San Francisco Bay.

The utility that operates the 30-inch diameter line said it was trying to find out what caused the steel gas pipe to rupture and ignite. Federal pipeline safety inspectors were on the scene Friday afternoon.

"It was just an amazing scene of destruction," National Transportation Safety Board vice chairman Christopher Hart said.

He said federal investigators will analyze the pipeline's condition, along with its maintenance history, pressure levels and the safeguards put in place to prevent pressure from building up. Hart said the NTSB will also look at the training and experience of the people who operated the pipeline and screen them for alcohol and drugs.

State Assemblyman Jerry Hill, who represents San Bruno and surrounding cities, said he has heard multiple reports from constituents who had alerted PG&E of gas odors in the neighborhood before the disaster.

The residents "deserve to know if PG&E used the correct procedures in the days and weeks leading up to this disaster," Hill said. The utility said it was checking its records for the complaints, but added that none of its crews were at work on the line Thursday.

Transmission lines like the one that burst in San Bruno deliver natural gas from its source to distribution lines, which then carry it into neighborhoods before branching off into homes.

Over the past two decades, federal officials tallied 2,840 significant gas pipeline accidents nationwide - including 992 in which someone was killed or required hospitalization, according to the Pipeline and Hazardous Materials Safety Administration.

Those accidents killed 323 people and injured 1,372.

Jacquelin Greig, 44, her daughter Janessa, 13, and Jessica Morales, 20, were identified by the San Mateo County Coroner's Office as having died in the fire. The three other people killed have yet to be identified.

Greig lived in a house just yards from the source of the blast. In her job with the California Public Utilities Commission, she worked to protect consumers from soaring monthly gas bills or dangerous pipeline expansions, co-workers said.

"This is so difficult for us because we're such a small group," said her co-worker Pearlie Sabino. "She does a lot of cases related to natural gas, that's the irony of it."

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