It’s been a week since Southern California Gas Co. permanently sealed off the leaking natural gas well in its Aliso Canyon storage facility near Porter Ranch, capping months of methane and other gases spilling into the air.
But just how much was lost?
Researchers from UC Irvine, UC Davis and elsewhere took dozens of air samples over the course of the nearly four-month spill, some from the ground and some from a plane flying above the area.
They estimate that, all told, the blowout spewed around 100,000 tons of methane into the air, which would make it the nation’s single-largest release of that gas.
California regulators recorded video of the moment the leak was sealed (the gas is invisible to the naked eye, but can be viewed on infrared camera):
“This was just a huge event,” said study co-author Stephen Conley of Scientific Aviation and UC Davis in a statement.
At its peak, the leak doubled the methane emissions rate for the entire Los Angeles basin. Another way to think of it: On average, the well lost enough gas every day to fill a balloon the size of the Rose Bowl.