On a normal day in Porter Ranch, residents can step outside their quiet suburban homes and breathe fresh air regularly swept clean of pollutants by strong winds—2008 LA Times profile on the affluent San Fernando Valley neighborhood even cited the windswept Porter Ranch air as some of the cleanest in the city. But for several weeks now, the same winds that normally refresh the atmosphere have been wafting in the fumes of a nearby gas leak that has residents suffering headaches, nosebleeds, and nausea. According to the LA Times, the Southern California Gas Company is struggling to plug a natural gas leak in the nearby Santa Susana Mountains, and it may be several months before air quality returns to normal.
The gas leak was first discovered in Southern California Gas Company's Aliso Canyon storage facility on October 23; the company attempted to plug the leaking pipe casing located several hundred feet below the surface of the well, but were unsuccessful, which means they'll now have to drill a relief well to plug the leak, a construction process that will take months to complete.
Meanwhile, "gas is flowing into the earth and seeping up through the ground," and residents of Porter Ranch are suffering through what the gas company calls "short-term symptoms" caused by odorants added to natural gas to aid leak detection. These short-term symptoms have added up to a long-term problem for many, though, and the South Coast Air Quality Management District has received nearly 500 odor complaints since the leak was discovered a month ago. Air samples taken in Porter Ranch residential areas turned up methane measurements of 616 parts per million (normally about 2 parts per million) as well as increased amounts of toxic benzene.
A report issued by the California Air Resources Board found that from October 23 to November 20, the gas leak in Aliso Canyon has been pumping 50,000 kilograms of methane into the air every hour. In that nearly one-month period, the gas emanating from the leak adds up to one-quarter of the total methane emissions in all of California. The air quality board has also found that 0.8 million metric tons of carbon dioxide, the equivalent of driving 160,000 cars for a year or consuming 90 million gallons of gasoline, has been leaked into the air near Porter Ranch.
Meanwhile, regulators say the gas company has failed to keep state officials in the loop about the well's condition, and so they are now required by the Division of Oil, Gas, and Geothermal Resources to provide detailed information to the public about the leak, including video of the well and a complete schedule for the drilling of the relief well that will plug the leak. The LA City Council will also officially meet with the gas company and air quality officials to asses the full magnitude of the gas leak and whether any improprieties may have occurred.
· Natural gas leak that's sickening Valley residents could take months to fix [LA Times]
· Report on greenhouse gas emissions from Aliso Canyon leak [LA Times]
· Wind-swept but comfy on L.A.'s fringe [LA Times]