More than five weeks since natural gas was discovered seeping from an underground well in the Santa Susana Mountains, prompting neighborhood complaints, Southern California Gas Co. representatives told the Los Angeles City Council Tuesday that the company would stop using the well after the leak is fixed.
But it still could take months before workers can get the seepage at the company’s Aliso Canyon storage facility to stop.
Officials from the private utility told the council Tuesday that a relief well was being constructed to address the leak -- a process that will take three to four months. Once that's done, the problem well will be cemented, shut down and permanently abandoned, they said.
"Unfortunately, this is not one of our prouder moments," Gas Co. President and CEO Dennis Arriola said.
He apologized for "the concern, the discomfort, the inconvenience, the frustration, the confusion and the bad smell" caused by the leak, which was discovered Oct. 23.
The well is more than 1 mile away and 1,200 feet in elevation above the nearest homes in the Porter Ranch area, and the leak does not threaten people’s health, the Gas Co. has said.
Nonetheless, hundreds of residents have taken the company up on its offer to relocate them to free, temporary accommodations.
Locals have complained of symptoms related to the rotten-egg-smelling odorants — mercaptans — that are added to odorless natural gas to help detect leaks.
“Exposures to these chemicals are generally not expected to lead to permanent or long-term health problems,” the Los Angeles County Department of Public Health stated in a fact sheet last week.
Mercaptans can, however, cause irritation to the skin, eyes and respiratory system, the department said. In addition to irritation, symptoms can include coughing and congestion, shortness of breath, nausea, dizziness and headaches.
Matt Pakucko of the advocacy group Save Porter Ranch told KTLA Tuesday morning -- before the council meeting -- that the smell is not the problem, but personal health impacts are.
"They keep saying ... there is no long-term health risk associated with breathing these chemicals. That's because there's never been a long-term study," Pakucko said. "We are the long-term study. The residents of Porter Ranch are going to let the world know what it's like to breathe this stuff."
Meanwhile, in addition to health worries, state regulators have raised serious concerns about the environmental impact of the leak.
The amount of methane — a potent greenhouse gas known as a climate pollutant — being emitted from the leak is equivalent to about a quarter of all statewide methane emissions, according to a preliminary estimate from the California Air Resources Board. Natural gas is about 80 percent methane.
The report estimated about 800,000 metric tons of carbon dioxide equivalent had been emitted by the leak through Nov. 20, and noted that the global-warming impact of methane is many times that of carbon dioxide.
“The relative magnitude of emissions from the leak compared to other sources of methane in the State underscores the urgency of stopping the gas leak,” the Air Resources Board report stated. “This comes on top of problems caused by odor and any potential impacts from exposure.”
The Times has reported the leak has the same effect as driving 160,000 cars for a year.
The Aliso Canyon storage facility, opened in 1972, uses a 7-inch pipe that descends 8,500 feet to a natural gas deposit underground, according to Gas Co. documents.
Several hundred feet below the surface, gas appears to be leaking from the pipe’s casing into the surrounding earth near the well.
L.A. City Councilman Mitchell Englander, who represents Porter Ranch, and City Attorney Mike Feuer last week called for state utility and gas regulators to investigate.
Aliso Canyon is one of four Gas Co. storage facilities in Southern California.
The company has created an Aliso Canyon leak webpage where updates are being posted.