A federal task force created following the Aliso Canyon natural gas leak near Porter Ranch issued dozens of recommendations Tuesday aimed at bolstering safety at underground gas-storage fields, including design changes to ensure that a single "point of failure" in a well cannot lead to an uncontrolled leak.
In a roughly 90-page report, the Interagency Task Force on Natural Gas Storage Safety issued 44 recommendations on topics including well integrity, response to a gas leak and reliability of energy supplies.
"No community should have to go through something like the Aliso Canyon leak again," U.S. Secretary of Energy Ernest Moniz wrote in a message included with the report. "The recommendations in this report outline the steps we can take to prevent such an incident in the future.
Now, it is up to (the) industry to implement these recommendations in a timely fashion, while state and federal officials develop regulations that enhance the safety of underground storage facilities in the United States."
The report's recommendations include a call for new wells to be designed to ensure a "single point of failure" cannot lead to an uncontrolled flow of leaking gas, and that old "single point-of-failure wells" be phased out. It also called for storage field operators to adopt monitoring programs, integrity tests of wells and leakage surveys.
The document also address responses to future large-scale leaks, calling for early creation of a "unified command" structure and advance establishment of emergency air-monitoring plans. The Aliso Canyon natural gas leak began Oct. 23, 2015, at the Southern California Gas Co. storage facility and forced thousands of residents to relocate temporarily.
The leak was shut down 16 weeks later, on Feb. 11. By that time, the leak had spewed more than 100,000 tons of methane into the air, making it the largest methane leak in U.S. history, according to a study released in February by UC Davis, the National Oceanic and Atmospheric Administration and others.
At the peak of the leak, the amount of methane pouring into the air from the damaged pipe was double the rate of methane emissions from the entire Los Angeles basin, according to the study. Even after the leak was capped, many residents continued to report health problems such as migraines and respiratory irritation.
SoCalGas spokesman Chris Gilbride said the utility is reviewing the report, but said the company cooperated fully with the task force "and is committed to supporting forward-looking and reasonable regulations that promote safety at natural gas storage facilities."
"In accordance with new regulations and state laws, withdrawal and injection of natural gas will only occur through newly installed inner tubing of wells approved for use by the Division of Oil, Gas and Geothermal Resources," he said. "Consistent with the report's recommendation, physical barriers, or casings, around the new inner tubing will provide a secondary layer of protection against potential leaks.
"SoCalGas has replaced the inner tubing of every DOGGR-approved storage well with new pipe," he said. "In total more than 40 miles of new piping has been installed."
Gilbride said the company is also using an infrared methane-detection system and performing continuous well-pressure monitoring, along with twice- daily visual well inspections and video scanning of the wells.
Sen. Barbara Boxer, D-Calif., pushed for the creation of the federal task force, and she called the report "an important first step toward protecting our communities from suffering another crisis like the one we saw at Aliso Canyon." "The recommendations from this task force would reduce the chance of future gas leaks while also strengthening protections for public health and the environment," Boxer said.