Bay Cities crew rams into PG&E gas lineBy Greta Mart
Martinez police officers and ConFire personnel kept up a vigilant watch for possible ignition sources.
Five hours after a construction crew ripped open a natural gas pipeline in the heart of downtown Tuesday, PG&E welders still struggled to manually stop the steady whoosh of escaping, highly-flammable vapors.
The smell of rotting eggs - methyl mercaptan PG&E adds to the odorless, highly flammable natural gas to enable detection - permeated the blocks surrounding the intersection of Marina Vista and Ferry Street into the evening. Local police and firefighters formed a perimeter around the rupture site to prevent any ignition sources from nearing the spewing invisible gas.
Just after 10:30 a.m., a Bay Cities Paving and Grading crew, working on the Marina Vista Streetscape Improvement project, bulldozed into a two-inch gas line encased within another non-pressurized pipe roughly 1.5 feet in diameter, located near the center of the intersection.
A PG&E spokesperson confirmed Wednesday that the distribution pipe was installed in 1933.
Within 15 minutes, said City Building Department manager Don Salts, PG&E workers arrived on the scene, along with emergency responders from several agencies.
At a distance of roughly ten feet from the broken pipe, the leaking gas made a muffled roaring sound, like a distant train whizzing through a tunnel.
Finding no shut-off valve on the section of broken pipe itself, PG&E workers were forced to move 200 feet to the south and manufacture a valve, hurriedly jackhammering up a section of pavement and digging roughly four feet down to unearth another section of the pipe. After cutting through a tangle of disused pipes, two welders grappled to crimp the visibly corroded distribution pipe as a PG&E supervisor looked on from street-level.
On Wednesday, a PG&E spokesperson was quick to point out the event was not a gas leak, rather a "third-party dig-in," adding that whether the pipeline was new or 77 years old, as was the line involved in Tuesday's incident, "we would have had the same situation. They damaged our pipeline," stressed PG&E's Nicole Liebelt.
"They hit one of our distribution lines. We encourage all residents and construction crews to always call 8-1-1 before you dig, so that we can come out and mark and locate our facilities," said Liebelt. Asked it that had occurred prior to the start of the Marina Vista Streetscape project, Liebelt replied company representatives had visited the construction site on Monday and "marked and located our facilities. We have it fully documented."
Liebelt described the repair process as similar to a punctured water hose.
"Typically you will pinch it off [further down the line] to stop the water flowing. The reason it took us an extended period of time [to stop the gas flow] was we did encounter several challenges, there were several substructures and as we excavated a second hole to pinch the line, we encountered [other pipes] not in service."
On Tuesday afternoon, Bay Cities Vice President Marlo Manqueros told the Gazette his workers had hit a two-inch pipe he called a stub-out line.
"We understand that one of our pieces of equipment hit a line that was a stub-out line, where PG&E cuts a line and leaves a portion and caps it. It was not marked or shown. We have been kept away from the site so we have not yet had the ability to investigate," said Manqueros via phone from Bay Cities' Concord headquarters, speculating that the stub-out pipe was alongside a main line that Bay Cities had long-since identified. "If you can't see it and don't know it's there .... I don't think it will impact the progress of the [Marina Vista Streetscape] work."
At 4:40 p.m., Salts reported that PG&E had managed to install a shut-off valve, interrupting the leak that discharged an unknown volume of natural gas into the atmosphere over several hours.
Liebelt said the company wouldn't be able to provide an estimation of the scope of the leak until after it had concluded an investigation.
According to Salts, PG&E "ran their gas main through an abandoned water line [that stretched] across the intersection ... PG&E inserted [the two-inch natural gas line] into the [several-inches in diameter] water pipe, that's why it looks bigger."
When asked why the company had installed a distribution line inside an abandoned, ancient water line, Liebelt said "I don't have information about our pipe being in a another pipe. No one can speak on PG&E and our facilities. We maintain our equipment and they struck our line."
In a subsequent telephone interview, Liebelt said Salts' assertion the pipe was positioned in an abandoned water pipe was "not correct. Our pipeline was in a casing or larger pipe. The casing was not pressurized and we use them when our lines cross other infrastructure."
"PG&E had to drop back a safe distance and install a line stop," said Salts at the end of the workday on Tuesday. "It looked to me [the PG&E workers] were going to be welding in a new section of pipe. We've been in contact with PG&E about relocating their pipeline and they are working on that."
Several business owners with establishments surrounding the impacted site, already disgruntled with the City's and Bay Cities' inept handling of the Marina Vista construction project, expressed fury with a day's worth of lost profits because of Bay Cities' bumbling.
Ferry Street Station proprietor Gina Millar said she sent an emailed request to the City requesting reimbursement for the business she lost.
"The smell was so bad that [my customers] left their drinks on the bar and walked out," said Millar. "A firefighter came in and said you can leave if you want to, but the [City-wide warning] siren didn't go off. Then they said it was a shelter-in-place. They were telling people not to go down Ferry but they didn't tell us."
Marina Market's Gurcharan Khinda was noticeably agitated as he said his sales for the day were 'zero.'
"For the past three or four hours, I've had no customers. This is very bad," said Khinda.
Cathy Riggs, working in her framing shop immediately adjacent to the pipe rupture, said a firefighter entered and told her to shut her doors and windows.
"I stayed because I had lots to do ... but later I offered a soda to one of the firefighters and he said they weren't even close to shutting down [the leak], so I took my show on the road," said Riggs. "First there was a whole bunch of people, all looking at the problem, and then suddenly it was a ghost town."
Contra Costa County Fire Protection District Battalion Chief Bryan Cisterman explained yesterday that the difference between the recent San Bruno disaster and a possible Martinez explosion was the exploded San Bruno pipe was 30 inches in diameter as opposed to the two-inch pipe under Ferry Street.
"What would most likely have happened in this case would be a flash back into the pipe [as was the case in the Walnut Creek pipeline explosion in 2004 that killed five] when a backhoe popped a line with 1300 pounds of pressure. You have an explosion when the gas builds up in a confined space," said Cisterman.
In Tuesday's event, although gas was leaking continuously for several hours, it quickly dissipated in the open air.
But his crew was taking no chances, said Cisterman. Firefighters stayed for more than five hours at the rupture site to ward off errant cigarette butts or sparks from passing vehicles.
Salts, on behalf of the City, said Tuesday, "we apologize for the inconvenience. It was unanticipated."
Copyright ©2010 Martinez News-Gazette. Published 10/28/2010.