Nearly four months of environmental contamination and civic disruption in Porter Ranch came close to an end Thursday when work crews pierced the underground casing of the damaged Aliso Canyon gas well and started injecting it with a mud-like compound.
"The well is no longer leaking," said Jimmie Cho, senior vice president of gas operations and system integrity for Southern California Gas Co.
The final step is for concrete to be pumped into the well, a process that could begin as soon as Friday, and for state regulatory officials to declare that the leak has ceased.
By Thursday afternoon, residents were already beginning to notice one major difference: No more gas odor that has driven so many from their homes.
"Mom, I don't smell anything," 7-year-old Aaron Paull said as his mother, Michele, pushed a shopping cart into a Ralphs grocery store.
For the nearly 5,000 households that moved out of Porter Ranch alarmed about health risks from the leak, the news brings mixed relief.
It's a moment of celebration, said Paula Cracium, president of the Porter Ranch Neighborhood Council, but there still is a lot of work ahead.
"It changes from controlling the crisis to now navigating recovery," Cracium said. "Homeowners have been injured. Property values have been injured. There's going to be a version of PTSD as they get a whiff of any odor in their home."
Residents of the northern San Fernando Valley community were more guarded than optimistic.
"It's really hard to trust anybody right now," said Amy Masliah, who lives in neighboring Chatsworth and moved to a hotel to escape the fumes. "Once they confirm that the air is clean enough for us to go back to our home, that my home is not contaminated, then I will feel much better."
At Wednesday night's neighborhood council meeting, residents raised concerns that chemicals from the leak — methane and odorants — have gotten into their furniture and carpeting.
Most of the families will not be distracted by the leak being stopped, Cracium said. "They still want to know that their homes are safe," she said.
Los Angeles City Councilman Mitchell Englander, who represents communities affected by the leak, emphasized that the next phase of the crisis is critical: that the entire facility be declared safe and life in Porter Ranch and surrounding cities returns to normal.
"This community's been through a lot for a long period of time," he said. "Their sense of belonging, their quality of life has been ripped apart."
Even though the financial fallout for Southern California Gas Co. is still being calculated, the leak so far has cost it nearly $300 million, with 67 lawsuits pending, according to a filing with the U.S. Securities and Exchange Commission,
Robert Weisenmiller, chairman of the California Energy Commission, said Wednesday that his agency will be tracking all of the company's costs to make sure they are not allocated to ratepayers.
The Aliso Canyon leak was discovered the afternoon of Oct. 23. At its peak in November, it was spewing nearly 60,000 kilograms of methane an hour into the atmosphere.
After a series of unsuccessful efforts to stop the venting from the top of the well, crews from a Texas company that specializes in well blowouts began to drill two relief wells that would intercept the damaged well.
The damaged well, known as SS25, extends 8,748 feet into a porous, permeable layer of sandstone that is crowned by a layer of nonporous rock, the capstone, that keeps the gas from escaping.
Drilling the first relief well began Dec. 4. It was located 1,500 feet from SS25 and was angled so that it would hit the casing at the capstone.
At the time, one state regulatory official described the process of hitting the 7-inch-diameter pipe at the bottom of SS25 from a distance of a mile and a half "like trying to hit a quarter-inch target from the distance of a football field."
The procedure required crews to periodically withdraw the drill pipe to measure its proximity to SS25, a process that took nearly a day before they could recommence drilling.
A second relief well was planned as a precaution, in case the first well failed. Drilling on that well was scheduled to begin Feb. 15.
FOR THE RECORD
Feb. 12, 3:40 p.m.: An earlier version of this article said work on the second relief well was begun in January.
Wednesday, crews made a "soft touch" with the concrete at the bottom of the well.
Thursday morning, the drill from the relief well began to bore into the inch-and-a-half concrete casing that surrounds the half-inch steel casing. Once it pierced the casing, crews began to pump a mud-like compound into the well.
For the next 24 hours, they will monitor the mud for evidence of escaping gas. In the absence of bubbles, they will start injecting concrete.
As the gas company continues monitoring the well, state regulators will conduct inspections and pressure tests to determine that the concrete has sealed the well. Those tests will allow them to certify that SS25 is dead.
"I would think that if this doesn't work, it would be really ugly," said resident Pat Pope.
Masliah can't wait for officials to confirm that the leak has stopped.
"I miss my beautiful home," she said. "I really do. I have a garden that's paradise to me. I want to go back home so bad."
Once regulators have determined that the leak has stopped, residents in hotel rooms will have eight days to move back to their homes, in accordance with terms of the agreement between the utility and the Los Angeles city attorney's office.
If they are in a house or an apartment with a lease, they may stay until the lease ends.
Rep. Brad Sherman (D-Porter Ranch) wants the California Air Resources Board to certify that the air surrounding the Aliso Canyon field is free of natural gas before residents have to return home.
L.A. County supervisors voted Tuesday to approve a motion, introduced by Supervisor Michael D. Antonovich, that requested utility officials to provide customers with as much as 30 days to relocate back to their neighborhoods.
The leaking well, one of 115 gas wells at the Aliso Canyon facility, has opened debate over the safety of the storage field, one of the nation's largest with a capacity of 86 billion cubic feet.
Many of them are corroded and mechanically damaged, the gas company said.
"The very first priority is making sure no gas is added to the storage facility until every single well is inspected," said Englander, adding that older wells should be taken out of service and shut-off valves mandated on those that remain.
"This is a game-changer," he said.
Times staff writer Louis Sahagun contributed to this report.
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