Rodger Schwecke of SoCalGas draws a basic diagram of how the relief well will intercept and stop the leak during an interview as methane gas leaks from the SoCalGas Aliso Canyon Storage Facility well SS-25 in the Porter Ranch neighborhood of Los Angeles, California on Wednesday, December 30, 2015. The Aliso Canyon gas leak (also called Porter Ranch gas leak) was a massive natural gas leak that started on October 23, 2015. According to Wikipedia, an estimated 1,000,000 barrels per day was released from a well within the underground storage facility in the Santa Susana Mountains near Porter Ranch. The second-largest gas storage facility it belongs to the Southern California Gas Company (SoCalGas), a subsidiary of Sempra Energy. On Jan. 6, 2016, Governor Jerry Brown issued a State of Emergency. The Aliso gas leak carbon footprint is said to be larger than the Deepwater Horizon leak in the Gulf of Mexico. On Feb. 11, 2016 the gas company reported that it had the leak under control. On Feb. 18 state officials announced that the leak was permanently plugged. An estimated 97,100 tonnes of methane and 7,300 tonnes of ethane was released into the atmosphere, making it the worst natural gas leak in U.S. history in terms of its environmental impact. &copy; 2015 Patrick T. Fallon