Nearly 100,000 tons of methane billowed from the ground over more than three months from a breach deep underneath Standard-Sesnon Well 25 at the Southern California Gas Company’s Aliso Canyon storage facility, making it the largest leak of its kind in United States history.

But since natural gas is invisible, very few people knew about the leak outside of the SoCalGas team of engineers until residents nearby started complaining of foul odors, headaches, nosebleeds and nausea. Even then, not everyone in the vicinity noticed.

“The prevailing wind actually was such that probably half the people in Porter Ranch never smelled anything,” according to Dave Clegern of the California Air Resources Board (ARB).

Even after I had hiked up to the Aliso Canyon natural gas facility’s back gate during the event, I was unable to detect the gas with either my nose or an infrared camera.

It wasn’t until the non-profit Environmental Defense Fund released an aerial, infrared video showing a bird’s-eye view of the plume that anyone knew just how catastrophic the leak was.

But SoCalGas had known about – and activists charge – could have prevented the leak.

Learn why methane is such a potent contributor to climate change. Click here if you cannot view this video.

While methane leaks occur all along the natural gas supply chain, the Aliso Canyon blowout has been called the mother of all “super-emitters,” a type of rare event that accounts for a disproportionately large amount of emissions. Seen as outliers until recently, large gas blowouts often go unreported. That could change now that Aliso Canyon has brought attention to what appears to many critics to be a lack of oversight of the natural gas industry.

“At last count I think there are 10 bills in the California legislature that address oil and gas in some form or another, so it certainly is an issue that has raised its head partly because of this incident,” says Damon Nagami, a lawyer for the non-profit National Resources Defense Council.

On the national level, President Barack Obama announced the formation of a “methane task force” in the wake of the Aliso Canyon leak. The Environmental Protection Agency is rethinking the way it calculates methane emissions, citing new, more accurate reporting methods. Additionally, a bill introduced in the House of Representatives, The Natural Gas Storage Act, aims to hold gas storage facilities responsible for meeting new safety standards. Rep. Brad Sherman, a Democrat who also happens to be a Porter Ranch community resident, proposed the legislation.

Ramon Alvarez at the EDF headquarters in Austin, Texas.

“A super-emitter just means a very large emissions source,” said Ramon Alvarez, a senior scientist with the Environmental Defense Fund, in an interview at the non-profit’s Austin, Texas headquarters. “A good chunk of the emissions come from a small percentage of sites or sources that are way far from the mean,” said Alvarez. “They exist; they’re not a fiction.” It may sound counter-intuitive, but according to Alvarez, these super-emitters are generally left out of emissions reports.

Source:"Reconciling divergent estimates of oil and gas methane emissions" and the EDF. Click here if you cannot view this video.

There are more than 5,000 oil and gas wells in Los Angeles alone.

Zoom out from the site of the leak to explore the wells in your neighborhood. Each dot represents a well. Click on a well to see its operator, status, type and SPUD date, which is when the well was originally drilled. You can find the entire history of a well by searching its API number on DOGGR's website.

  1. Well Status:
  2. A: active
  3. I: idle
  4. P: plugged
  5. U: unknown
  6. C: cancelled
  7. B: Buried-Idle

  8. Well Types:
  9. OG: Oil & gas - production
  10. DG: Dry gas - production
  11. WS: Water source - production
  12. OB: Observation well
  13. SF: Steamflood - injection
  14. WD: Water disposal - injection
  15. WF: Waterflood - injection
  16. AI: Air injection
  17. SC: Cyclic steam - injection
  18. PM: Pressure maintenance - injection
  19. GD: Gas disposal - injection
  20. GS: Gas storage - production & injection
  21. LG: Liquefied gas - production & injection
  22. GT: Geothermal

It’s important to note that this doesn’t mean that Aliso Canyon-sized leaks happen often across the country.

In part, its scale made the Aliso Canyon leak more significant. Its emissions were not just considered high for a leaking well. In fact, according to Alvarez, the emissions from that one site were nearly on par with those of entire production regions, such as the vast gas production, gathering and processing activities in the Barnett Shale area of Texas, or in the Uinta Basin in Utah.

The immense size of the leak, however, is just one side of the coin. The vehement blowback against SoCalGas and various state regulatory agencies by the Porter Ranch community has been a driving force for change at all levels of government. What began as an unpleasant odor causing unexplained headaches snowballed into a community movement to plug the leak and shut the facility down completely and permanently.

Eventually, two schools had to be relocated away from Porter Ranch due to health concerns, and more than 6,000 residents filed housing relocation claims with SoCalGas’ community resource center. The upscale, suburban neighborhood still feels the effects of the leak, even after the California Department of Conservation confirmed through a series of five independent tests that the well has been permanently sealed.

The South Coast Air Quality Management District (AQMD), a local-government agency responsible for controlling primarily emissions from stationary sources in the metropolitan region, held a judicial board hearing in February. Residents testified that the unpleasant scent associated with mercaptan, a chemical added to normally odorless natural gas to make it detectable, was still hanging over their homes.

They expressed concern and anger that their requests for home testing and cleanup were going unheard, and that people were still getting sick after the well was reportedly plugged. But the most evident problem in the community continues to be the lack of trust associated with the operators of the well.

Residents at the hearing were not surprised to learn that SoCalGas is lobbying against State Bill 380, proposed legislation that requires testing of the remaining wells at Aliso Canyon. “So far, that’s exactly what’s happened from day one,” said Matt Pakucko of Save Porter Ranch, a community activism group. “They have volunteered nothing.”

“They haven’t checked the homes they’re asking people to moved back to,” said Rep. Sherman, backing up the residents’ complaints to the judicial board. “To tell people to move back to their homes without checking the home is missing one essential step.”

Rep. Sherman’s urging the AQMD board to take action encapsulated much of the tension between citizens, SoCalGas, and the various response agencies. Here was a resident of Porter Ranch, a member of Congress, expressing his own frustration with the lack of accountability and action by the AQMD, whose officials in return argued that they didn’t have the authority to act. They passed the buck to the governor’s office and state agencies, mainly the Public Utilities Commission and the Department of Conservation, even suggesting that Rep. Sherman had as much influence over those state agencies as does the AQMD.

Rep. Brad Sherman (D-California) speaks at the AQMD hearing.

The frustration mounting in the auditorium was palpable. Audience members grew more secure in loudly criticizing decisions, to the point that officials on the judicial board had to ask the crowd to come to order more than once.

It’s not hard to understand the mob mentality when it comes to Porter Ranch. Oil and gas companies are easy targets, and, in the minds of many residents, SoCalGas has reneged on promises to make up for the leak by pressing displaced residents to return home immediately after the leak was plugged. Private attorneys descended on the community early on to represent those who believe their health or businesses suffered as a result of the leak, and several lawsuits have been filed naming SoCalGas as a defendant.

But SoCalGas could claim to be a victim of the blowout, too. The nearly 100,000 tons of leaked methane cost them an estimated $15 million in lost revenue. Housing rental rates spiked as a result of the company’s subsidizing resident relocation efforts, making it more difficult to find temporary homes for families and costing SoCalGas even more.

At least one resident of Porter Ranch, who wished to remain anonymous, admitted to me that his family filed a relocation claim, despite staying in their home, in order to collect “reimbursement” from the utility. On top of that, the cost of plugging the leak and fighting legal battles may overextend the utility’s $1 billion insurance policy.

Despite these financial setbacks, though, SoCalGas’ parent company, Sempra Energy, surpassed its 2015 earnings targets, and awarded its CEO, Debra Reed, a $3.17 million bonus, a move that Los Angeles City Councilman Mitchell Englander called “appalling.”

State officials are also asking SoCalGas to do something to offset the emissions. The state Air Resources Board has drafted a mitigation plan that focuses on reducing agricultural and landfill emissions, which make up about 75 to 80 percent of California’s methane emissions.

The plan is “to attack the largest sources as quickly as we can,” according to Clegern, since methane’s effects on the atmosphere are most potent in the first 20 years.

But like current regulations on the oil and gas industry, the plan is mostly bark and little bite. “They have pushed back on our authority because, the way this is written, it is essentially a voluntary program,” says Clegern of the state ARB. That agency is operating on the assumption that SoCalGas will back up the commitment the company’s president, Dennis Arriola, made in a letter to Governor Jerry Brown Jr. shortly after the discovery of the leak that promised to cover costs of mitigation.

The voluntary element could change, however, depending on the outcome of a lawsuit filed against SoCalGas by the ARB and the state Attorney General.

Dave Clegern enters the ARB headquarters in Sacramento.

“The lawsuits are a very visible sign that something very, very wrong happened here,” says Nagami of the NRDC. “Now that the leak has been plugged, the conversation is going to turn to ‘what happened and how can we prevent this from ever happening again?’”

The exact cause of the blowout is still under investigation, but much attention has been paid to a safety valve that SoCalGas claims to have removed in 1979 for repairs, and never replaced. “There was no requirement to have inspection of the well frequently enough to detect that a safety valve was broken and needed to be replaced,” according to Nagami.

“There’s no regulation in place requiring a company that has old infrastructure to go back, check it and replace what’s not working,” he said.

But the operators say they did go back to check the safety valve. They claim to have found that it was old and leaking, and they elected to remove it in order to repair or replace it. Only it was never replaced, which raises the question: isn’t an old, leaky safety valve better than none at all? Would Porter Ranch be in this mess if the leaky valve was still there?

Even in 1953, the Tide Water Oil and Gas Co., which originally drilled the well for the purpose of oil production, was required to install and maintain safety equipment at all times. This was stipulated in writing on each piece of correspondence with the California Department of Natural Resources Division of Oil and Gas while it was approving modifications through 1973, when the well was repurposed for natural gas storage.

But SS-25 was not designated a “critical well,” as defined by the California Environmental Quality Act, since it was not situated less than 300 feet from a home, allowing the valve to be removed, contrary to the state Natural Resources agency’s stipulation. And that wasn’t the only one.

“They’d taken them off apparently all those wells,” according to Clegern, who believes the focus on the safety valve may be missing the larger, systemic problem. He noted that many of the wells at Aliso Canyon are over 70 years old, and perhaps overdue for a leak.

“DOGGR (the Department of Conservation’s Division of Oil, Gas, and Geothermal Resources) is the agency that’s supposed to be regulating underground injection wells,” according to Nagami, who says they have acknowledged their regulations could be stronger. Gov. Brown ordered the Department of Conservation to require daily inspection of natural gas wells using infrared leak-detecting technology, among other stipulations including regular testing of safety valves and verification of wells’ mechanical integrity. But those regulations are only temporary unless legislative packages make it through the State Senate and Assembly.

California Sen. Fran Pavley and Senate President Pro Tempore Kevin de León have introduced a bill package that aims to strengthen well standards, require routine inspections, install safety valves and develop emergency plans in the event of another incident, as well as stipulates that the utility, not the ratepayers, should have to pay any financial penalty stemming from the leak.

SB 380 is one bill that would continue Gov. Brown’s moratorium on injections and withdrawals of natural gas from Aliso Canyon until all the wells at the facility are tested to ensure their safe operation.

While the bill explicitly stipulates testing of the 115 Aliso Canyon wells, the ripples are being felt on a much wider scale. Shortly after the bill was introduced, the operator of a gas storage facility elsewhere in the state asked Senator Bob Huff, a co-author of the bill, if it would affect their field. “’Absolutely,’” Sen. Huff said he replied. “I wasn’t threatening. It’s just a statement of fact.”

Those regulatory ripples extend to other natural gas fields throughout the state, where all eyes are on Aliso Canyon, and to the citizens of Los Angeles. A controversial report on the city’s energy supply claims up to 14 days of rolling blackouts may occur this summer if the moratorium continues.

Matt Pakucko of Save Porter Ranch delivers public comments at the inter-agency workshop

At an April 8 inter-agency workshop to address the potential for blackouts, residents toting posters with the slogan “SHUT. IT. ALL. DOWN.” called the report “scare tactics” to keep the facility open.

There are a lot of cooks in this kitchen, and they’re making a giant pot of alphabet soup. The AQMD, ARB, DOC, DOGGR, OEM, CPUC, and CNRA are only some of the state agencies tasked with some form of response.

With so many additional tiers of government all requiring cooperation, some frustrating redundancies, as well as jurisdictional clashes and regulatory gaps are bound to occur.

“I think what you’re seeing is the normal governmental response to this kind of a disaster, which is, ‘OK, what are the next steps, how do we fix the agencies to make sure they bring their protocols into the 21st century,’” explained Kip Lipper, chief advisor on energy and the environment to the Senate president, in his office in the Capitol.

State officials have been looking into short-term climate pollutants like methane for the better part of a decade, according to “Senator Lipper,” as Sen. Huff calls him, due to the large role the advisor plays in the Capitol. The ARB’s research has pinpointed certain goals that must be met in order to curb the effects of climate change. Much of this research went into Sen. Ricardo Lara’s Senate Bill 1383, which aims to reach those goals by reducing methane emissions 40 percent by 2020.

“This just didn’t happen in a vacuum,” said Lipper, explaining the context surrounding the legislation. “There was a lot of attention given to the short-lived climate pollutants prior to the Aliso Canyon leak, but Aliso Canyon kind of galvanized everybody.”

Take a look around the Capitol and click the music notes to hear Lipper explain the bills addressing the Aliso Canyon leak. Click here to see the original photo.

Sen. Lara’s bill addresses methane and other “short-term” polluters like black carbon and refrigerants, but the ARB’s research will also affect bills that specifically target the Aliso Canyon regulations put in place by Gov. Brown’s executive order. The goal of those is to “replace that regulation with something that’s a little more beefy and a little more detailed, just because that was put together rather quickly,” said Clegern. “We’ve been working on this for a couple years but now we have kind of a catalyst to crystallize where we need to go with it.”

The Aliso Canyon leak has also been a catalyst in federal legislation. Rep. Sherman’s House Resolution 4578 proposes to create minimum standards and requirements for underground gas storage facilities and impose user fees on their operators. But gridlock in Congress and industry lobbying could stall the bill from becoming law.

The environment versus fossil fuel energy is a partisan issue even in blue California’s progressive legislature. “I don’t know that I’m breaking ranks,” said Sen. Huff, a Republican, but in an assembly appropriations vote on SB 380, the issue was split mostly along party lines. “The Democrats voted yes, the Republicans laid off with the exception of one Republican who voted for it.”

If the threat of blackouts in Southern California due to natural gas shortages at electrical power plants was a scare tactic, it worked. Sen. Huff relayed a conversation he had with an unnamed Republican assemblywoman who was concerned there were not enough safeguards for electrical grid stability. Still, he is optimistic the bill will become law. The bill made it through that appropriations hearing and passed through the Assembly on a near-unanimous vote. Next, it will go back to the Senate for concurrence. Since SB 380 is an “urgency” bill, it needs a two-thirds majority to go into effect immediately. If they can’t get the votes, the bill would have to go through as a simple majority, and would not take effect until January.

No one is calling what happened at Aliso Canyon a blessing. “What happened there was unconscionable,” said Clegern of the Air Resources Board. “The idea that you’re put out of your home for months, how long, who knows? Because someone wasn’t taking care of a facility that in many cases you didn’t know was there… there’s nothing you can call that but bad.”

But the leak did shine a light on systemic failures and provided a roadmap for agencies and legislators to follow, which could prevent a similar leak in the future. “What’s the saying about generals?” Sen. Huff asked, rhetorically. “They usually fight their last battle again - that’s how you prepare. You want to learn from your mistakes and, going forward, try to make fewer of them.”

David Merrell is a news producer and recent graduate from the USC Annenberg master's of journalism program. You can reach him by email or on Twitter.

To access original media files used in this story, click here.