A giant stream of potent climate-warming gas – methane – is blowing hundreds of feet into the air in Los Angeles County for the seventh week.
The release cancels out hundreds of smaller efforts over more than a decade to clamp down on escapes of the gas, a priority because in the short term, methane is a far more powerful climate-warming gas than carbon dioxide.
Pilots flying low have been told by the FAA to stay clear of the plume for fear of ignition.
More than 1,800 families have sought relocation due to the vapors.
Southern California Gas Co. officials say it will be months before it can be stopped.
The mainly methane gas is pouring out of the ground near a damaged well used to inject gas into an old sandstone oil field for storage.
“I think what we are seeing is probably one of the single largest releases of methane in California history,” said Tim O’Connor, who used to inspect major facilities like refineries for the Bay Area Air Quality Management District and works for the Environmental Defense Fund.
“People I speak with who are experts in the field say this is biggest, most complex leak that they have ever seen.”
Authorities estimate the rupture in the well, perhaps more than a mile deep, is sending 100,000 pounds of methane into the air per hour.
Methane traps heat more powerfully than carbon dioxide during its approximately 20-year stay in the atmosphere, giving it an outsize role in rising sea levels and disrupted weather.
The Aliso Canyon Gas Storage Field, covered with wells, is owned by Southern California Gas Co., a subsidiary of Sempra Energy, based in San Diego.
“We have never had an escape this large,” said Gillian Wright, vice president for customer services for Southern California Gas.
“I have to really emphasize this is an extremely rare event.
The extent and the difficulty of resolving this leak are highly, highly unusual.”
All the methods the company has tried so far to kill the well have failed.
Now experts who fought the Kuwaiti oil field fires have joined the effort.
The safety of the some 100 workers on the site is also a concern.
Wright said that is why on some days, the company cannot perform certain work.
If the wind is blowing methane over certain equipment, crews cannot start that equipment, she said.
As of the weekend, 1,800 families, ill or frightened by sulfurous gas drifting down from the site, have been relocated from Porter Ranch, paid for by the gas company.
An additional 1,433 families have asked to be moved, with some still deciding, said Melissa Bailey, a company spokeswoman.
Among those who have left are George Chang and Susan Gorman-Chang. Gorman-Chang said the first time she felt the full impact of the unfolding events was midway through her habitual five-mile run, when she felt the strong smell of gas, or to be precise, an additive intended to give an odor to the otherwise odorless gas.