Beyond the countless, sometimes smaller, details about the ongoing invisible, but historic, methane leak in Southern California …

Aerial view of methane leak
Infrared camera look at methane leak (source: EDF video screenshot).

… and apart from reports of displaced residents of the Porter Ranch community at the north end of the San Fernando Valley, it’s worth reflecting on a handful of statistics:

  • Since the leak began on October 23, some 90,000 metric tons of methane gas have been released. On Jan. 6, the Environmental Defense Fund published aerial footage of the leak using an infrared camera that makes the leak visible.
  • Methane is short-lived compared with carbon dioxide, lasting only about 12 years once emitted into the atmosphere. The lifetime of CO2 is harder to precisely pin down because CO2 is not destroyed over time and it cycles through the atmosphere, oceans, and land – some of it lasting in the atmosphere for hundreds to thousands of years.
  • Pound for pound, the comparative impact of methane on climate change is more than 25 times greater than CO2 over a 100-year period. But keep in mind each CO2 molecule’s far longer atmospheric lifetime.
  • In the first three months, the Southern California Gas Company leak had emitted the equivalent of 2.1 million metric tons of carbon dioxide, more greenhouse gas than 440,000 cars emit in one year.

Timetable for stopping the leak

The company on January 25 said this leak, now said to be one of the worst fossil fuel disasters in U.S. history, is expected to be plugged 8,400 feet below ground by the end of February. As of late January, a relief well was about 200 feet from the spot where it’s intended to intercept the leaking well – but it must hit a target about the size of a watermelon to precisely align the relief well with the target well.

Once the relief well reaches its target, the gas company says it plans to pump heavy fluids and mud into the relief well to stop the leak. Cement will then be pumped in to displace the fluids and seal the leaking well.

One bit of good news: the rate of emissions has fallen substantially, down from a peak of 58,000 kilograms per hour on November 28 to 18,400 kilograms per hour on January 21. Southern California Gas says the rate has fallen because the company has increased controlled withdrawals of gas from the underground reservoir – reducing pressure on the leaking well.

Why the leak might have occurred

Why did this leak happen in the first place? The Huffington Post reported on January 21 that the Aliso Canyon site was built in 1953, “long before there was any standard for encasing wells in cement from top to bottom to prevent these kinds of accidents.”

Southern California Gas also could have prevented the leak had it replaced a safety valve that had stopped working in 1979, the Huffington Post reported. “However, because California law only requires safety valves on wells within 100 feet of a road or a park or within 300 feet of a home, SoCalGas opted not to replace the hard-to-find piece.”

The thrust of the Huffington Post piece – “Why Everyone Should Be Worried About The California Gas Leak Disaster” – is that the leak comes as no surprise . . . and more should be expected given the dearth of regulations nationwide to make these kinds of gas storage facilities safer.

The Aliso Canyon facility is one of 14 of its kind just in California. Meanwhile, some studies estimate that 2 to 4 percent of natural gas nationwide routinely escapes into the air between the time it’s taken out of the ground and when it’s consumed – and this is apart from major leaks like the one at Aliso Canyon, the Los Angeles Times reported on January 24.

In California, the state’s Division of Oil, Gas & Geothermal Resources has announced emergency regulations for all the state’s natural gas storage facilities, but critics say they fall far short of what’s needed.

“You look at things like the Santa Barbara oil spill that just happened, the oil spill that happened over the last few years in L.A., the things that are happening on a regular basis in places like Kern County and Porter Ranch – these are all indicators of a failing regulatory system that can’t keep us safe from things that are inherently dangerous,” Linda Capato, Jr. with the environmentalist organization told the Huffington Post.

Proposed federal public lands methane rule

Meanwhile, the federal government is moving to limit methane emissions from oil and gas operations on public land. The proposed Department of the Interior rule on natural gas leaks would not apply to situations like the one in California, but “it’s aimed at accidental gas leaks and at the process of venting and burning off leaked gas – known as flaring – from oil and gas wells on public lands,” the New York Times reported on January 22.

While the federal action comes at a time when the Southern California methane leak is in the news, it’s part of the Obama Administration’s climate change initiatives, proposing to cut methane emissions from the oil and gas industries by 40 to 45 percent from 2012 levels by 2025.

At Aliso Canyon, where more than 2,600 families have had to flee their homes, the CEO of Southern California Gas Company, Dennis Arriola, said he thinks the potential public health fears have been overblown, CBS news reported on January 23.

“I’ve been out here almost every day since October 23rd,” Arriola said. “I feel totally safe.”

Bruce Lieberman, a long-time journalist, has covered climate change science, policy, and politics for nearly two decades. A newspaper reporter for 20 years, Bruce worked for The San Diego Union-Tribune...