Photographer: Patrick T. Fallon/Bloomberg

Gas Field That Sprung Biggest Leak in U.S. History Set to Reopen

Updated on
  • Aliso Canyon stopped taking gas after leak in October 2015
  • State says safe to operate field at limited capacity

Almost two years after the biggest gas leak in U.S. history sprung from a Sempra Energy natural gas storage field in Southern California, the state is ready for the complex to reopen.

Sempra Energy’s Aliso Canyon field near Los Angeles is safe to operate at about 28 percent of capacity, with the ability to store as much as 23.6 billion cubic feet, the state Division of Oil, Gas and Geothermal Resources and Public Utilities Commission said Wednesday in a joint statement. The long-anticipated finding follows months of extensive inspections and well tests by engineers.

The shut field has tested the limits of California’s power and gas markets, constraining supplies on the hottest and coldest days. The region’s gas supplies are now sitting at the lowest levels seasonally in more than a decade.

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While federal and state energy regulators -- as well as Sempra -- have warned that the region could be at risk of energy shortages with Aliso Canyon offline, opposition to restarting the complex has only intensified since the leak forced thousands of people to evacuate their homes. Governor Jerry Brown is calling for the permanent closure of the field, and California Energy Commission Chairman Robert Weisenmiller said Wednesday he’s ready to prepare a plan that’d have it shut within 10 years.

For more on how the closure is affecting California, read this story.

Local residents and some state lawmakers had called for the field to remain closed until regulators determine the root cause of the well blowout. The incident has already cost Sempra’s Southern California Gas utility, which operates the field, almost $800 million.

“I’m confident that the field is safe and can be reopened,” State Oil and Gas Supervisor Ken Harris said in a call with reporters Wednesday.

‘Rigorous’ Requirements

Sempra’s Southern California Gas utility has met and “in many cases” exceeded the “rigorous requirements of the state’s comprehensive safety review”, the San Diego-based company said, adding that gas injections into the field wouldn’t resume immediately.

State officials estimate the field will be reopened within two weeks after Sempra conducts a leak survey and a flyover to measure methane emissions, state Public Utilities Commission Executive Director Timothy Sullivan said Wednesday during the call. Regulators capped the amount of gas that can be stored at the site to “just enough to avoid energy disruptions”, Sullivan said.

Gas will only flow through newly installed steel tubing inside of wells, and Sempra said it has implemented other safety practices including around-the-clock pressure monitoring.

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