One of the largest natural gas leaks in the history of the United States has finally been sealed shut. The leak started in October 2015 at a well in the Aliso Canyon Gas Storage Field in Southern California, emitting more than 94,000 metric tonnes of methane into the air over homes in the Porter Ranch neighbourhood of Los Angeles. It wasn’t immediately evident to the public that something was wrong until many residents began complaining of headaches and nosebleeds. The governor of California declared a State of Emergency on Jan. 6 and more than 6,000 residents were forced from their homes since the leak was discovered.
Methane is a greenhouse gas, absorbing the sun’s heat and warming the atmosphere. It’s the main component of the natural gas used in most homes. There are large stores of methane beneath the seafloor and in organic matter frozen into the permafrost in the Arctic. Pound for pound, it can be 25-times more powerful at trapping heat in the Earth’s atmosphere than carbon dioxide, and can take upwards of 12 years to breakdown. These facts make it particularly disastrous to hear that during the leak, California’s entire methane emissions rose by roughly 20 per cent, pushing the state’s total annual emissions by around 6 per cent.
The Aliso Canyon Gas Storage Field is one of the largest in the US, and the 115 gas wells are operated by the Southern California Gas Company. As many as 39 of the site’s 115 wells were developed prior to 1954, and lawmakers say they need to be brought up to modern standards to help minimize the chance of another leak happening in the future.
Early next week, the Senate energy committee will hear a bill by Senator Fran Pavley to extend a moratorium on injecting gas into Aliso Canyon, ordered by Governor Jerry Brown, until Southern California Gas completes safety measures that ensure the community won’t be exposed to future gas leaks. By the senator’s account, two-thirds of Porter Ranch residents near the storage facility favor closing the operation for good.