Environment & Science

Porter Ranch: Massive gas leak could be capped next week

File: SoCal Gas has set up a community resource center on Tampa Avenue near the entrance to their Aliso Canyon Storage Facility near Porter Ranch.
File: SoCal Gas has set up a community resource center on Tampa Avenue near the entrance to their Aliso Canyon Storage Facility near Porter Ranch.
Maya Sugarman/KPCC

An adviser to Gov. Jerry Brown told Porter Ranch residents Thursday that the massive nearby gas leak could be capped by the end of next week.

Wade Crowfoot, Brown’s deputy cabinet secretary, said the final phase to intercept the ruptured well near Porter Ranch is expected to start Monday.

“We understand it would be a process of over four, even five days by the time you have the initial control, or stop, of the leak until when it would be determined stopped by independent assessment,” he said at the weekly meeting of the Porter Ranch Community Advisory Committee, a Southern California Gas Company-sponsored group that functions as a clearinghouse of information between various officials and residents.

He cautioned the estimate is a best-case scenario, one that could be delayed if any phase of the plan goes wrong.

SoCal Gas released the following statement also cautioning that the timetable could change:

"As we have said previously, our schedule is to stop the leak by the end of February, if not sooner. While we cannot confirm how long the process will take, we are working to do this as safely and expeditiously as possible."

Stopping the leak

Southern California Gas has been drilling a parallel, or “rescue” well about 8,500 feet below the layer of rock that contains the giant field of natural gas. A drill bit in the rescue well is scheduled to bore into the leaking well on Monday. Heavy fluid, then drilling mud will be pumped down the rescue well into the leaking well to temporarily seal it shut.

Once the leak is stopped, cement will be pumped down to permanently seal the well a day or so later. That takes a day or two to dry. Then SoCal Gas will test to make sure gas is not coming up from the ruptured well.

The state Division of Oil Gas and Geothermal Resources will conduct an independent assessment to make sure the leak is plugged and air quality regulators from the state Air Resources Board and South Coast Air Quality Management District will also be testing for natural gas, Crowfoot said.

The California Air Resources Board did its latest flyover of Aliso Canyon and Porter Ranch Thursday. The air quality testers concluded that the leak is putting out methane at about 30 percent of what it was leaking at its height. By the time the leak is plugged, an estimated 5.3 billion cubic feet of methane will have escaped, adding to the greenhouse gases that trap heat and contribute to the warming of the atmosphere.

The concrete casing of the well is thought to have broken about 500 feet below the surface, Crowfoot said. The plan is to keep that casing intact so that it can be removed from the ground and examined. The well has been leaking since October.

The blowout at the largest natural gas-storage facility in the West has uprooted 4,300 residents and spewed more than 2 million tons of climate-changing methane.

Residents have complained of headaches, nausea, nosebleeds and other symptoms. Public health officials blame the woes on an odorant added to the gas and said there shouldn't be long-term health problems.

Gas crisis continues

Once the leak is stopped, however, the natural gas crisis it triggered is not over, said Ed Randolph, director of the California Public Utilities Commission’s energy division.

It will take months for safety inspections of some 114 other gas injection and storage wells at the Aliso Canyon Natural Gas Storage Facility to return to normal operations, Randolph said.

During the inspections, the company is barred from injecting gas into the underground reservoir – or making large withdrawals from it.

Normally, the field can hold 86 billion cubic feet of natural gas, but it's being held to just 15 billion cubic feet to lower the pressure and risk that other aging wells might also leak.

That's the minimum amount the L.A. Basin needs on its coldest days when heaters get cranked up, and on hottest days when local power plants turn to natural gas to meet air conditioning demands. The Los Angeles Department of Water and Power uses natural gas as a backup source of fuel.

Gas supplies to customers like LADWP could be curtailed if the region appeared to be running low on natural gas, Randolph said. He said the CPUC and LADWP are drawing up a plan that will conserve natural gas supplies and prioritize which power plants should get sparse natural gas over the summer.

He said the leak revealed the CPUC  did not have adequate backup plans for the possibility that Aliso Canyon’s underground storage might be unavailable for months.

A study is underway to assess the long-term viability of Aliso Canyon and three other fields, at Playa del Rey, Honor Rancho in the Santa Clarita Valley and at La Goleta in Santa Barbara County.

Going home

Gillian Wright, a SoCal Gas executive in charge of relocating local residents, said she is in talks with the Los Angeles City Attorney’s office to determine how much longer the company would pay relocation costs to give families time to organize their returns home. Wright said she expects to have an answer this weekend.

Homeowner representatives asked that a state agency or county Public Health Department randomly select and inspect about 100 homes for contamination of air, water, textiles and outdoor surfaces to be sure they're safe before anyone returns.

Crowfoot, the governor’s advisor, said he’s been told that the rotten-egg smell added to natural gas so that it can be detected does not linger in carpets or furniture and that opening windows and running air conditioners for a few hours should clear out any stale air. However, he said he would inquire about potential testing.

This story has been updated with a statement from SoCal Gas.