Sempra Energy's Southern California Gas Co. (SoCalGas) unit reported Monday that it expects to stop the nearly three-month-old natural gas storage well leak at its Aliso Canyon underground facility "by late February, if not sooner.”
"Our schedule to control and stop the leak in February is consistent with the plan we have submitted to state regulators," said SoCalGas' Jimmie Cho, senior vice president for gas operations. He said the relief well drilling that began Dec. 4 is expected to reach the bottom of the 8,500-foot deep well next month.
The announcement from the beleaguered gas-only utility came amid reports over the weekend that the state has postponed for safety reasons a stopgap measure to burn some of the leaking gas.
Separately, on Sunday plaintiffs attorneys representing dislocated residents in the upscale Porter Ranch residential development near the leak challenged the gas utility’s claims that the volume of methane being emitted has been reduced significantly and that there are no real health risks from benzene being given off as part of the leaking gas.
SoCal Gas is facing hundreds of millions of dollars of costs related to the leak, which some critics are citing as one of the nation's biggest environmental breaches ever.
With the help of major well-killing experts, the utility and officials from seven state agencies started two relief wells last month, underscoring a growing frustration about the leak, which experts said is a first for similar gas storage facilities. The leak, initially thought to be a routine incident, has continued unabated (see Daily GPI, Dec. 16, 2015).
In response to a shorter-term effort to capture large amounts of the leaking gas and burn it a safe distance from the wellhead, the California Public Utilities Commission (CPUC) on Thursday stopped the work until a long set of questions and concerns outlined in a three-page letter to SoCalGas are resolved. The CPUC sought answers from the utility by Tuesday (Jan. 19), but on Monday SoCalGas halted the project.
Local news media and environmentalists have seized on the CPUC letter, which referred to possible "catastrophic" consequences if the attempt to capture and burn the leaking gas does more damage to the already fragile wellhead. The concern is about creating an explosive air-gas mixture and/or igniting the leaking gas.
The head of the South Coast Air Quality Management District's (SCAQMD) hearing board told the Los Angeles Times that the plan is now on hold, pending review and approval by local fire, CPUC and federal officials.
Meanwhile, attorneys suing SoCalGas on behalf of angry residents who are calling for the 86 Bcf, 3,600-acre underground storage field to be closed have challenged SoCalGas' characterizations that the leaking volumes had decreased by 60% and that only trace amounts of benzene have been measured around Porter Ranch since the leak was discovered Oct. 23 (see Daily GPI, Nov. 12, 2015).
The attorneys said they have videotapes showing leakage from the wellsite taken last week and a month earlier, alleging that the volumes appear to be the same. Similarly, they allege to have 14 separate measurements of benzene that were "twice the level considered normal."
In a fact sheet used by both the utility and SCAQMD, benzene is characterized as a "trace component of natural gas," of which the biggest contributors in the Los Angeles area are listed as "mobile sources" -- cars, trucks, ships, etc. State health officials said Thursday "nearly all measured benzene concentrations in the Porter Ranch community during the leak are similar to background levels generally found in the L.A. area."