Sempra unit failed to analyze natgas leaks at Aliso Canyon before 2015 accident: state report

FILE PHOTO: Crews from Southern California Gas Company and outside experts work on a relief well at the Aliso Canyon gas field above the Porter Ranch section of northwest Los Angeles, California in this December 9, 2015 pool photo. REUTERS/Dean Musgrove/Pool/File Photo

(Reuters) - A Sempra Energy subsidiary did not conduct detailed inspections or analyses of leaks at the Aliso Canyon gas storage facility before the major 2015 leak that has cost the utility more than $1 billion, according to a state report released on Friday.

The report, an independent analysis of the cause of the 2015 leak commissioned by the state's public utility and oil and gas regulatory agencies, found the leak occurred because contact with groundwater caused microbial corrosion that led to the rupture of a well casing.

The report found SoCalGas, as the utility is known, never conducted failure investigations on 60 casing leaks at Aliso Canyon going back to the 1970s, according to a statement by the California Public Utilities Commission.

(Reporting by Nichola Groom; Editing by Marguerita Choy)