Aliso Canyon Leak Plugged but Safety Issues Linger

After nearly four months, the leaking well at the Aliso Canyon underground gas storage facility in the Porter Ranch neighborhood of Los Angeles has finally been plugged. Preliminary estimates from the California Air Resources Board (CARB) put the total leakage at 5.4 billion cubic feet of gas, the primary component of which is potent heat-trapping methane. In the next hundred years, the gas that escaped from Aliso Canyon can heat the globe as much as the yearly emissions from more than 700,000 cars.

The leak seriously disrupted the lives of Porter Ranch's tens of thousands of residents, who feared for their health and safety, as well as that of their family, friends, and neighbors. People in Porter Ranch and around the state and country want to see concrete steps taken to ensure that something like this won't happen again - at either Aliso Canyon or the 13 other underground gas storage facilities in California ... or the hundreds more scattered across the nation.

There are several crucial things that need to happen to prevent future disasters at Aliso Canyon and elsewhere, including:

  • All the wells at Aliso Canyon and other underground storage facilities need to be physically inspected to make sure they're not currently leaking or at risk of leaking. This includes evaluating the casing, tubing, packers, and cement in each and every well to make sure there aren't any holes, gaps, leaks, corrosion, or erosion. Any problems need to be fixed, and if they can't be fixed the wells need to be plugged and abandoned.
  • Aging infrastructure must be addressed. As described in more detail below, all of California's underground gas storage facilities are in depleted oil or gas fields that were discovered decades ago and contain aging wells not built to today's standards. These wells need to be subject to the most stringent monitoring requirements. If they exhibit persistent problems, their construction should be updated or they should be plugged and abandoned.
  • Regulations governing these and other injection wells need to be completely overhauled. California's current statewide regulations specifically for gas storage projects run a whopping total of 86 words. They don't include any rules for how to convert old wells to storage wells or even how to build new wells. Inspections to look for holes inside the wells are required only once every five years, and the rules don't say anything about how often gas storage wells have to be inspected for problems with the cement or for corrosion. All of these issues regarding how to build and maintain wells may have played a role in the Aliso Canyon leak.
  • Rules must be enforced. Even the strongest regulations in the world are useless without enforcement. Reports show that the Division of Oil, Gas, and Geothermal Resources (DOGGR) has been failing to enforce even the weak protections that are on the books for injection projects like underground gas storage. DOGGR regulators have been bypassing critical protections and failing to fix problems once they're found.

The size of Aliso Canyon leak was extraordinary but smaller leaks happen throughout the oil and gas production chain every day. Unfortunately at the national level, although EPA has put in place and proposed important new rules that will apply to new sources of emissions, it has not yet put forth a plan to regulate sources already in operation. It's a no-brainer that if we want to be serious about controlling methane emissions, then any rules must apply to existing sources, which is why we and our partners are calling on EPA to do just that.

This disaster shone a bright light on both the antiquated infrastructure used to store gas and the outdated regulations governing these facilities.

The Aliso Canyon oil field was discovered in 1938. The deep geologic formation, in which the gas is currently stored, once held oil. The failed well - the Standard Sesnon 25 - was originally drilled in 1953 as an oil production well. It was converted to a gas storage well 20 years later - without any major upgrades, even though it was never designed or constructed for that purpose and the design was likely already outdated. And no major upgrades to the well's construction have occurred since then.

The failed well is far from the only one of that age or design. Almost half of the 114 active storage wells in Aliso Canyon were drilled before 1954 - again, not for the purpose of gas storage, but for oil production. The vast majority of the remaining wells were originally drilled 15 years ago or more.

The story is no different for the other 13 storage facilities in the state. The youngest was discovered in 1958 (the Los Medanos Field in Contra Costa County, operated by PG&E) and the oldest in 1929 (the Playa del Rey Field in LA County, operated by SoCalGas). In fact, SoCalGas itself highlighted concerns with its aging infrastructure in 2014 testimony before the California Public Utilities Commission (CPUC) asking for a rate increase to address "...a negative well integrity trend." In language eerily prescient of the Aliso Canyon disaster, SoCalGas warned that without an enhanced inspection and repair program, "SoCalGas will continue to operate in a reactive mode (with the potential for even higher costs to ratepayers) to address sudden failures of old equipment. In addition, SoCalGas and customers could experience major failures and service interruptions from potential hazards that currently remain undetected."

DOGGR's regulations for these facilities haven't been updated in decades, and what regulations the agency does have are totally inadequate to prevent future incidents. In the same testimony to the CPUC, SoCalGas stated that while it "currently meets existing requirements under DOGGR regulations, the possibility of a well related incident still exists, given the age of the wells and their heavy utilization."

Leaders and lawmakers around the state are acutely aware of these issues and are taking steps to address them. For example:

  • Governor Brown's emergency order prohibits injection into Aliso Canyon "...until a comprehensive review, utilizing independent experts, of the safety of the storage wells and the air quality of the surrounding community is completed." DOGGR and independent experts developed a battery of tests that wells will have to undergo before injection is allowed to begin again.
  • DOGGR put in place emergency regulations aimed at addressing immediate safety issues at underground storage facilities around the state and has also begun the process to develop permanent rules.
  • Various bills are moving through the state legislature to address the safety of Aliso Canyon specifically and underground gas storage projects more generally.

The process of modernizing these facilities and how they are regulated won't be easy or fast, but it is critical to ensuring the safety of communities and protection of the environment.

About the Authors

Briana Mordick

Senior Scientist, Land & Wildlife and Climate programs

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