Almost two months after the discovery of a natural gas leak at a storage site near Los Angeles, the company responsible says it can’t identify the cause or how much methane has been released.
Southern California Gas Company updated legislative staff at the state Capitol Monday.
The company noticed the leak in October at its largest natural gas storage facility, north of Los Angeles. The company believes the lining of the about 8,700 foot well failed about 500 feet below the surface.
"We can’t send a camera down, there’s no way to really observe the conditions within the well, so we’re doing this all based on deduction," says Gillian Wright, vice president of customer services.
Since then, company contractors have made repeated--and failed--attempts to plug the leak, which outgoing State Oil and Gas Supervisor Steve Bohlen says is unusual.
"I asked the engineers who have been with the division 20, 30-plus years and the answer was this is unique," says Bohlen. "I know globally these are not common. It’s not always easy to diagnose them and get them closed anywhere near as rapidly as you would like."
At a time when the state is touting efforts to reduce greenhouse gases, neither the company nor regulators know how much gas has escaped. A preliminary state measurement found a leak rate that would add a quarter to California’s daily methane emissions, but that could taper as gas escapes, relieving pressure inside the well.
The company says it has used about 10 percent of the fuel stored in the facility, but hasn't determined how much further it will draw down the leaking reserve or how much of the leaking methane it can recapture.
Contractors are now drilling a new tunnel to reach the well bottom. Wright says they recently finished the first 1,200 feet, in a process that could take up to four months.
Southern California Gas Company has so far moved about half of the nearly 4,000 residents who have requested temporary relocation from the gas smell.