Climate Mitigation Plan for Gas Leak at Aliso Canyon Long on Ambition, Short on Details

For nearly four months, a massive leak at Southern California Gas Company’s Aliso Canyon natural gas storage facility in Los Angeles pumped nearly 100,000 tons of methane into the atmosphere – constituting the largest methane leak U.S. history. It took a heavy toll on the surrounding community, including forcing the evacuation of 1,800 homes.
Infrared image of the methane leak at Aliso Canyon
Credit: EDF

For nearly four months, a massive leak at Southern California Gas Company’s Aliso Canyon natural gas storage facility in Los Angeles pumped nearly 100,000 tons of methane into the atmosphere – constituting the largest methane leak U.S. history. It took a heavy toll on the surrounding community, including forcing the evacuation of 1,800 homes. It also took a heavy toll on the climate: pound for pound, methane is a greenhouse gas that’s up to 87 times more potent than carbon dioxide at trapping heat over the first 20 years following its release.  

The California Air Resources Board (ARB) today released its plan to mitigate the damage to the climate from Aliso Canyon, which rests on a commitment SoCalGas made back in December in a letter to Governor Jerry Brown. But while ARB’s plan sets a high bar in many respects, the limitations of relying on the gas company’s voluntary pledge have left it bereft of key implementation details and facing an uncertain future.

By Hook or By Crook

Chief among those uncertainties is the interplay between this process and a civil lawsuit ARB later joined in Los Angeles Superior Court against SoCalGas alongside the LA City attorney, the state attorney general, and the county of Los Angeles. Among other claims, the suit seeks relief that includes climate mitigation. Depending on how the lawsuit is resolved, SoCalGas may be ordered to undertake mitigation. For the time being, however, ARB’s mitigation program rests on the company’s voluntary commitment.

But whether by court order, consent decree, or voluntary agreement, we can expect the mitigation framework ARB developed will feature in the negotiations over how to account for the invisible catastrophe that occurred at Aliso Canyon between October 2015 and February 2016. So let’s take a look at what ARB proposed today.

Areas of Concentration

The plan proposes that SoCalGas fund a portfolio of emissions reduction projects over the next 5 to 10 years within three broad areas:

  1. Reducing methane emissions within the agriculture and waste sectors, which collectively are responsible for three-quarters of California’s methane emissions (e.g. by making biogas from methane captured at digesters installed at dairies, landfills, and wastewater treatment facilities);
  2. Reducing natural gas demand by increasing energy efficiency (e.g. by funding rebates for customers to install more efficient furnaces and water heaters); and
  3. Reducing emissions from methane “hot spots” not currently targeted under federal, state, or local laws (e.g. by plugging abandoned oil and gas wells).

Credit: California Air Resources Board

Within each category, ARB proposes scoring criteria that would prioritize local projects in nearby communities harmed by the leak and projects that provide co-benefits to California’s disadvantaged communities. But that’s where the details start to dry up. While ARB identifies important considerations in implementing the proposed plan (including project solicitation, selection, and verification), it makes no specific recommendations on how to proceed other than that oversight of program implementation be assigned to a third-party administrator approved by ARB. The rest “will be finalized only in the future.”

Achieving Full Mitigation

ARB’s primary task was to develop a program that would fully mitigate the greenhouse gas emissions from the leak. That, in turn, requires four key components: (1) accurately quantifying the total volume of leaked methane (ARB’s latest public estimate, based on flyover measurements, puts it at 94,500 tons, but the agency will issue a revised estimate later this summer after incorporating additional measurements from on-the-ground monitors); (2) employing appropriate global warming potentials (GWPs) in calculating SoCalGas’s total mitigation obligation to account for methane’s significant near-term climate impacts; (3) ensuring only reductions that are truly additional are eligible to count toward the mitigation; and (4) ensuring SoCalGas makes a sufficient financial commitment to fund the program.

The proposed plan delivers on the first three components. ARB smartly proposes to focus on achieving equivalent reductions in methane to diminish the necessity of using GWPs. But recognizing the imperative to reduce natural gas demand in light of the reliability challenges stemming from the loss of Aliso Canyon (California’s largest gas storage facility), ARB also proposes to fund energy efficiency projects that would require a conversion from methane to a carbon dioxide equivalent (CO2e). For these programs, ARB proposes to use a 20-year GWP, as it provides a better perspective on the speed at which short-lived climate pollutant like methane impact the climate. ARB also embraced a strong commitment to limiting the eligibility of mitigation projects to only those that “yield real, verifiable, and permanent greenhouse gas emission reductions that are additional to…actions that SoCalGas already is taking, will otherwise be legally obligated to undertake, or voluntarily agreed to prior to the natural gas leak at Aliso Canyon.”

Conversely, the plan defers consideration of the financial commitment required from SoCalGas. Without it, ARB cannot ensure the leak’s climate impact will be fully mitigated because there is no guarantee that the funding ultimately agreed to by SoCalGas will be adequate to achieve the required level of reductions. For that reason, ARB staff originally floated the idea of incorporating a financial “backstop” if the initial slate of funded projects underperform or otherwise fall short of delivering full mitigation. But the final plan is silent both on SoCalGas’s required financial commitment and any safeguards if the mitigation comes up short.

Time to Walk the Walk

If the gas company’s comment letter on the draft plan is any guide, ARB’s final plan may be destined for the “thanks but no thanks” bin. That would be a disappointing and shortsighted response for a company that markets itself as an environmental leader and is trying to regain the trust of the Porter Ranch community. While the pending litigation complicates the way forward, SoCalGas should embrace the key tenets of ARB’s mitigation plan and get to work righting the wrongs from Aliso Canyon – not fighting over the details.

The Porter Ranch community and the climate deserve nothing less.

Related Blogs