By Andrew Clark | Signal Staff Writer
Air quality managers issued a violation notice to Southern California Gas Company in connection to a second leak at Aliso Canyon in Porter Ranch earlier this month and after a legislator urged constituents to file complaints.
The South Coast Air Quality Management District received 15 complaints from residents Dec. 18 complaining of foul odors following a 50-minute leak that day. Senator Henry Stern, D-Canoga Park, said the leak had been resolved, but allowed for residents to file a complaint with the air quality management district.
“While the root cause of the 2015 blowout and the safety and need for the field in general is still being evaluated by state regulators,” Stern said, “this particular leak has been patched.”
Southern California Gas Company said the leak started at 4:55 p.m. Monday Dec. 18, but did not notify air quality officials nor the community until more than two hours after the leak started. The leak was started due to “failure of a flange gasket in a pressure vessel,” according to the air quality district.
“We take all nuisance odor incidents seriously,” said Wayne Nastri, SCAQMD’s executive officer. “SoCalGas and all facilities in our region have an obligation to protect residents from foul odors can that impact their communities.”
The air quality management district said a methane monitor at the Aliso Canyon site measured a peak concentration of 66 parts per million during the leak, more than 30 times the typical background methane concentration of 2 parts per million.
Aliso Canyon is the site of one of the largest natural gas leaks in history, with tons of methane gas being released into the air. The leak, which began in October 2015, was not sealed until February 2016.
The air quality management district filed a lawsuit against the gas company in January 2016 and obtained an administrative order requiring the gas company to conduct leak detection and to notify the public in the event of future leaks and other measures. The lawsuit was settled in February for $8.5 million.
The California Public Utilities Commission and the Division of Oil, Gas and Geothermal Resources approved the reopening of the storage site in July, but limited the capacity of the site’s holdings to 28 percent.
Stern said at the time of the reopening that there should still be seismic and fire safety analyses. His bill to determine the cause of the explosion, Senate Bill 57, stalled in the Legislature.