PG&E won permission from a state administrative law judge in San Francisco on Monday to reconnect a 3.8-mile natural gas pipeline in San Carlos to its transmission system at reduced pressure.
Line 147 has been closed off from the system, although kept at low< pressure of 125 pounds per square inch, since Oct. 7, in the wake the disclosure of internal PG&E e-mails that raised concerns about the safety of the line last year.
The reconnection was authorized by California Public Utilities Commission administrative law judge Maribeth Bushey after a PG&E attorney requested the action and the commission's safety advisory staff told her the reinstatement would be safe.
Attorney Joseph Malkin told Bushey at a hearing at the commission's headquarters that an outside consultant had concluded that the line was fit for service "without a doubt."
Malkin said that without the use of the line, the gas supply to local customers would have to be curtailed during the coming winter season when people are looking to turn up the heat.
Bushey approved reopening the line for the time being after consulting privately with the commission's safety advisory staff, which said it had no objection to the plan.
"We're going into the winter season ... We need to have a status quo operating system in the real world so we can go forward," Bushey said.
The order allows PG&E to reopen four valves that connect Line 147 with other lines, but requires it to keep the pressure at 125 pounds per square inch.
It will be in effect while Bushey and Commissioner Michel Florio conduct further proceedings this fall on whether the line can be safely
restored to its former maximum pressure of 330 pounds per square inch.
Bushey set a Nov. 15 hearing at which three senior PG&E executives and engineers will be questioned. She said she hopes to issue a proposed decision by Nov. 22, which would then be opened for public comment on Dec. 2 and placed before the full commission for a final decision on Dec. 5.
Greg Rubens, a lawyer for San Carlos, questioned whether the reopening, proposed by PG&E on Friday, would be risky.
"We still don't have answers that the proposal is safe," Rubens told Bushey.
After the hearing, Rubens said, "We're still concerned about the safety of the line. PG&E can't show us what's in the ground."
Rubens said he has been interviewing independent experts and hopes to hire one soon to act as a consultant to the city in preparation for the Nov. 15 hearing.
The isolation of the pipeline was ordered first by a San Mateo County Superior Court Judge on Oct. 4 and then by the commission on Oct. 8 at the request of the city.
City officials said they feared the pipeline was vulnerable to leaks after they learned of internal e-mails in which PG&E engineers in November 2012 raised concerns that the pipe was thinner than indicated in the utility's records and had showed corrosion.
In one email, former PG&E engineer David Harrison, now a consultant to the company, wrote, "Are we sitting on another San Bruno situation? ... Is the pipe cracked and near failure?"
A leak in another PG&E pipeline caused the explosion and fire in San Bruno on Sept. 9, 2010, that killed eight people, destroyed 38 houses and damaged dozens of other buildings.
PG&E initially asked in Friday's proposal for permission to reconnect the pipe at low pressure when the local temperature was forecast to be 50 degrees Fahrenheit or below.
Bushey announced near the start of today's hearing that the commission's advisory staff had said that plan would be safe.
But after Rubens said he had "a lot of questions," including a query about whether it was safe to turn the valves on and off in response to temperature variations, Bushey and Florio consulted privately with the staff and returned with a decision to allow the pipeline to be reconnected continuously, instead on an on-and-off basis.
"This is now a substantial change in what was proposed on Friday," Rubens told Bushey.