Southern California Gas has shut down one-third of the injection wells at Aliso Canyon, the giant underground natural gas storage facility near Los Angeles, Kallanish Energy reports.
The company, in an Aug. 28 letter to California state regulators, said a gradual buildup of pressure had been discovered in the casings of 13 of the 39 injection wells being returned to service. The company took them out of service.
Two wells have been fixed and returned to service, while 11 remain offline while the company investigates and corrects the problem, according to California media reports.
No natural gas was released into the atmosphere, the company and state officials said. The increased pressures never reached levels of concern, the company reported.
SoCalGas had resumed injections at Aliso Canyon on July 31, after two state agencies said the facility was safe to reopen.
In 2015-2016, Aliso Canyon was the site of the country’s biggest methane leak, which forced 8,000 people to evacuate their homes.
The facility is the largest natural gas storage facility in the West and can handle up to 86 billion cubic feet of natural gas. State officials have reduced that volume for increased safety.
The leak began on Oct. 23, 2015, and was contained on Feb.11, 2016. It is estimated 107,000 tons of methane and 8,000 tons of ethane escaped into the air. The cause of the leak remains under investigation.
SoCalGas paid a $4 million fine to resolve criminal charges. The utility faces additional lawsuits by state and county agencies and individuals.ate agencies are looking at the facility moving forward.