Following a highly publicized methane leak near the Porter Ranch neighborhood of Los Angeles, the Southern California Gas Company (SoCal Gas) agreed in August to pay $119.5 million to settle claims put forth by the city, county, and state. The leak began in October of 2015, in SoCal Gas' Aliso Canyon gas field. It took the company almost four months to stop the leak, during which time an estimated 109,000 metric tons of methane were released into the atmosphere—roughly the same amount as the entire Los Angeles Basin's yearly emissions, as Pacific Standard has previously reported.
In addition to causing Porter Ranch residents to experience bouts of headaches and nausea, the leak also contributed to global warming. (Although less prevalent than carbon dioxide, methane is a potent greenhouse gas.)
As Thomas Ryerson, a chemist with the National Oceanic and Atmospheric Administration, told Pacific Standard shortly after SoCal Gas finally plugged its leak, "One little thing going wrong has just rolled back years of emissions reduction efforts by the state of California."
A version of this story originally appeared in the December/January 2019 issue of Pacific Standard.