The substance in the pipes was compressor oil and all of the pipes are tied into a control station in Milpitas. The company spent millions of dollars to keep the compressor oil out and hadn't seen it in the pipes since November.
Only PG&E knows where corrosion took place because it will not disclose the location of any of its transmission lines -- for safety and security reasons.
Attention is now focused on the current pressure level inside the gas line that exploded.
PG&E revealed Friday morning that it has lowered the pressure by 20 percent in the remainder of the pipeline. The state asked the utility to do that earlier this week.
County officials are hoping to have all the fire debris removed by October 15, which is the start of the rainy season. The material has been tested, it's not contaminated, but the Air Quality Management District said it has to be treated as hazardous waste or as asbestos. Either way it will delay the removal of the debris.
This comes on the day that property owners are meeting with county and state officials to discuss possibly signing waivers allowing the county to remove the debris.
PG&E's pipeline secrecy sparks fear
PG&E's secrecy about its high risk lines is contributing to continuing high anxiety in San Bruno. Fear and uncertainty triggered an emergency situation Thursday at an elementary school less than a mile from the fire zone. The school was evacuated, and then closed for the day.
It was a sign of just how anxious people are in San Bruno. It is also a sign of the long road ahead; at City Hall an emergency meeting of the City Council ended with the Council declaring a local emergency. It was a formality that comes on top of a state emergency that was already declared in Sacramento, all designed to help bring moa resources to the victims.
All it took was for two mothers to say they smelled gas at Portola Elementary School Thursday morning and minutes later the 200 students were loaded onto buses and driven off campus.
"On PG&E's recommendation they said we should evacuate the students and staff," Superintendent David Hutt said.
It turned out to be a false alarm, but almost as soon as the report came in firefighters rushed to the scene, the crime scene tape went up, PG&E crews searched for gas leaks and parents raced to pick up their children.
"It's scary, it's really scary and not to know what's going on and why PG&E won't say where the gas pipes are..." parent Christina Elliott said.
Firefighters at the school said they do not believe the lines are near the school.
It is a community living on edge, a fear driven by the horror they witnessed but also by what they do not know -- where PG&E's other high-risk pipelines lie and whether they run through their neighborhoods or near their schools.
"A lot of people are on edge, they don't really know about the gas line situation," San Bruno Fire Battalion Chief Joe Tellas said.
PG&E still refuses to make its list of 100 high-risk pipelines public.
"The transmission lines, for security reasons, we don't release those maps," PG&E spokesperson Jeff Smith said.
It has been a week to the day since flames consumed this neighborhood and the cleanup is still ongoing. Just up the hill from the blast site, signs of PG&E's gas lines run along the street.
"See that orange post, they dug the whole street and went in there and then they went down," San Bruno resident Despina Sullivan said.
Neighbors have known about the pipes for decades, but they were never concerned until last week.
"I'd like to know what they can do to make sure that something like this doesn't happen again," San Bruno resident Bessie Zahiralis said.
Coroner official back in San Bruno neighborhood
Thursday afternoon, an official from the San Mateo County Coroner's Office was back at the scene of the San Bruno blast. They were called back to Claremont Drive after San Bruno police discovered what they thought to be human remains.
The house where the remains were found is belived to belong to the Bullis family. The three members of the BUllis family are among those listed as missing.
The coroner says that the investigation is ongoing and that there is no other information available at the moment.
SF officials tour San Bruno damage
San Francisco Fire Chief Joanne Hayes-White and Mayor Gavin Newsom Thursday got their first in-person look at the San Bruno damage and the pipeline that caused it. Newsom had ordered an infrastructure safety review, hoping to prevent a similar disaster in San Francisco.
"We wanted to take a look today and we had a very productive meeting with PG&E yesterday to begin discussion of age, location, maintenance schedule of gas transmission and distribution lines into San Francisco," Hayes-White said.
Hayes-White says she saw a schematic of the pipeline system, but was not given a map. PG&E says for security and safety reasons, it will not give a map of its system to anyone, including the governor, state emergency management officials or local fire chiefs.
Elisa Tovar, 22, and her father Jose collected what they could find amidst the rubble of what was their two-story, four-bedroom Claremont Drive house Thursday.
Firefighters helped open a safe where Jose's gun collection and some jewelry was stored.
"I'm scared to come back, I don't want to," Elisa Tovar said.
Elisa is afraid to move back, Jose is not. He does not think PG&E's maps make any difference one way or another.
"Everywhere you go, you don't know what can happen," he said.
Gov. Arnold Schwarzenegger says he is trying to get PG&E to release the list of the top 100 most at-risk lines to both first responders and the public.
CPUC sets up number to reported gas smell
The California Public Utilities Commission has established a toll-free number and e-mail address for anyone who noticed the smell. People can call (800) 789-0550 or send an e-mail SBFire@cpuc.ca.gov if they smelled the gas.
The NTSB has also set up a tip line for their investigation. They are interested in reports of a natural gas order or any plants dying. You can e-mail information or amature video related to this case to: email@example.com
ABC7 Continuing Coverage:
AUDIO: Fire dispatch recordings of San Bruno explosion
RAW VIDEO: Explosion captured on gas station video
RAW VIDEO: Reactions to explosion captured on video
RAW VIDEO: NTSB Monday afternoon update
Some San Bruno residents allowed to return
RAW VIDEO: NTSB Sunday afternoon update
RAW SKY7 VIDEO: Friday morning over San Bruno
VIDEO: Photographer's first-hand account of devastation
VIDEO: Eyewitness account
PHOTOS: San Bruno explosion
VIDEO: "I thought - this is judgment day"
VIDEO: Fire consumes neighborhood
VIDEO: Photographer captures images moments after blast