State oil and gas regulators say they completed a safety review of a Los Angeles gas storage facility where a blowout spewed methane for nearly four months. Based on that, they are setting some strict conditions for Southern California Gas Co. to reopen the underground field that blew a huge leak in 2015.
For starters, the field may hold only about one-third as much gas as it did before the leak, according to a statement Tuesday from the state Division of Oil, Gas and Geothermal Resources.
The agency said Tuesday that it would hold public hearings in February before deciding whether to let Southern California Gas Co. resume storage of natural gas at its Aliso Canyon facility.
The underground Aliso Canyon gas storage field near Porter Ranch has the capacity to hold 83 billion cubic feet, the statement said, but the amount of gas the company could put into the field available for delivery to customers would be limited to a maximum 29 billion cubic feet. That is in addition to an amount of gas necessary to maintain minimum pressure on the field.
Less gas in the field means it would operate at lower pressure levels. That lower pressure translates into less stress on the gas field's aging, but recently overhauled wells.
Aliso Canyon, the region's largest underground gas storage field, has been closed since a gas well disastrously blew out in 2015. The leak drove 8,000 families from their homes and led to mass complaints of nosebleeds, nausea, headaches and other maladies.
State regulators are taking the next step toward reopening the field near Porter Ranch. They announced a two-part meeting to be held February 1 and 2 to take public input on new conditions that could be imposed on field owner Southern California Gas Co.
The meeting will be from 5:30 p.m. to 9 p.m. on both Wednesday, Feb. 1, and Thursday, Feb. 2, at the Hilton Woodland Hills. The public may also submit comments about reopening and operating the gas field to Alisocomments@conservation.ca.gov.
The Public Utilities Commission will make a decision whether to reopen the field following analysis of public comment. That process could take weeks or months, officials have said.
SoCal Gas has been under orders to repair or improve aging wells at what is the largest natural gas storage facility in the West.
The state says less than a third of re-worked wells now pass the rigorous tests required after the blowout.
The risk of the aging wells to rupturing in an earthquake on the nearby Santa Susanna Fault was an open question at the Aliso Canyon gas field, one that merited further study, according to a letter signed by six representatives of the Sandia, Lawrence Berkeley and Lawrence Livermore national labs.
They said that while it’s common for scientists to study how buildings and other structures hold up during earthquakes, little is known about the risk to wells like those at Aliso Canyon. The field has 114 wells that were sunk 9,000 feet into the earth in the 1940s. Of those wells 34 have been overhauled to replace the inner tubing, and the rest have been temporarily plugged.
State Sen. Henry Stern introduced a bill Tuesday that would stop SoCal Gas from resuming gas injections until an independent state-ordered investigation into the root cause of the gas well blowout is completed.
“If we don’t know what went wrong, how can we prevent it from happening again,” the Canoga Park Democrat said in a statement.
This story has been updated.
Correction: An earlier version of this story inaccurately stated how many of the re-worked wells pass the tests required after the blowout. KPCC regrets the error.