One of the main Southern California wildfires blackening parts of northern Los Angeles County is suspected of being caused by a downed electric transmission line serving the Southern California Gas Co.’s (SoCalGas) largest underground storage facility in the area. The storage operations were shut down Oct. 13 and 50 employees and contract workers evacuated.

State and county fire officials investigating the Sesnon fire said last Thursday they suspected the power line serving facilities at the Sempra Energy utility’s Aliso Canyon storage operations was the culprit. A SoCalGas spokesperson last Friday told NGI the utility is cooperating with the investigation, but it has not been confirmed yet that the gas utility’s power line was the cause; it is only the suspected cause.

Given the recent state regulatory commission investigation and public hearing in San Diego County last Tuesday on two transmission line-caused wildfires a year ago in that area involving Sempra’s other utility, San Diego Gas and Electric Co., (SDG&E) state officials were concerned that under a regulatory quirk, the SoCalGas distribution power line does not fall under any mandatory third-party inspection.

The officials said that because the power line is not operated by an electric utility and is in an unincorporated area of Los Angeles County, there is no state or county regulation, or regular inspection, of its operation, according to a report in the Los Angeles Times.

In the meantime, the SoCalGas spokesperson said workers have returned to the Aliso Canyon facility in the Santa Susana Mountains in the far northwest end of the suburban San Fernando Valley section of Los Angeles, about 35 miles from downtown.

Aliso has an overall capacity close to 100 Bcf, using a former oil and gas field similar to many that dot the greater Southern California region. The Sempra utility’s three other underground storage operations — Honor Rancho, which is located closest to Aliso Canyon, farther north in Los Angeles County; Playa del Rey, near the Los Angeles International Airport; and Goleta, along the coast in San Barbara County — and were not impacted by the fires.

During last year’s wildfire siege in late October, the underground storage facilities remained unscathed by the many fires, as was also the case in October 2003, when utility electric systems were hit severely.

In the aftermath of more than a dozen fires that blazed through the region a year ago, the investigative unit of the California Public Utilities Commission (CPUC) concluded in a report released in early September that two fires — Witch and Rice — were caused in part by violations of state regulatory codes by Sempra’s SDG&E utility. A 32-page report from the CPUC Consumer Protection and Safety Division (CPSD) recommended starting a joint investigation of the utility’s role in the two fires, and last Tuesday’s public hearing is part of the continuing probe.

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