Utility officials in Southern California say they have determined the underground location of a pipe leak that has spewed natural gas into the air since late October — but it could be months before they are able to fix the rupture that has driven up the state's methane emissions and chased thousands of families from their homes.
Los Angeles Mayor Eric Garcetti has called the leak an "environmental disaster," and the Los Angeles Unified School District shuttered two area schools for the rest of the year.
Politicians and environmentalists in California are particularly sensitive to the toll the leak may take on the environment, especially after Gov. Jerry Brown doubled down earlier this year on the state's efforts to slash greenhouse gas emissions.
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The massive underground leak at a storage facility north of Los Angeles was reported by the Southern California Gas Co. on Oct. 23, and since then has emitted more than 72,000 metric tons of methane, according to the Environmental Defense Fund, which released an aerial video in conjunction with the nonprofit Earthworks that used an infrared camera to make the gas visible.
"Methane is in a category of greenhouse gases known as short-lived climate pollutants," California's Air Resources Board says on its website. "These types of gases remain in the atmosphere for a much shorter period of time than longer-lived climate pollutants, such as carbon dioxide (CO2); but when measured in terms of how they heat the atmosphere, their impacts can be tens, hundreds, or even thousands of times greater than that of carbon dioxide."
The ARB said in a November estimate that the leak may have added as much as a quarter to California's methane emissions between Oct. 23 and Nov. 20. As of 2013, methane emissions made up 9 percent of California's overall greenhouse gas output.
"SoCal Gas recognizes the impact this incident is having on the environment," company chief executive Dennis Arriola said in a letter to the governor earlier this month. "I want to assure the public that we intend to mitigate environmental impacts from the actual natural gas released from the leak and will work with state officials to develop a framework that will help us achieve this goal."
Thousands of residents of the nearby Porter Ranch community have been voluntarily relocated after many complained of nausea and other illnesses, and the company is paying to move those who say they have been made sick by the gas.
Los Angeles City Attorney Mike Feuer asked for a temporary restraining order on Dec. 22 that would force the company to speed relocation of affected residents and allow him to take depositions from SoCal Gas employees about the leak.
The company has said it is doing everything it can to plug the well that extends more than 8,000 feet underground, and help people who have reported illnesses. State and local agencies have been monitoring the air quality for weeks around the leak site in Aliso Canyon and in surrounding areas. While the levels of methane measured in the surrounding air aren't currently considered a serious health risk, according to the LA County Department of Public Health, substances called mercaptans that give the otherwise-odorless methane a pungent, "rotten egg" smell can cause irritation, dizziness and some breathing issues.
As of Monday, the company had placed 2,258 families in temporary housing, a spokeswoman told the Associated Press.
"For those experiencing health symptoms due to the odorant, we are continuing to offer home solutions that will help to reduce the smell indoors," Arriola, the SoCal Gas CEO, wrote to Brown on Dec. 23. "Our highest and most urgent priority is to stop the leak. We have hundreds of our employees, expert consultants and suppliers working around the clock to resolve this issue."
After attempting other methods to stop the leak, the company has begun drilling relief wells that would allow it to seal off the gas by pumping cement underground. SoCal Gas has said that the work to plug the well may not be complete until late March. On Sunday, the company said that it has drilled about 3,800 feet toward the target well, and that it is beginning work to drill a second, backup relief well.
"We are working as quickly and safely as possibly to complete this operation," Arriola wrote in his letter.