The true size of what’s likely the largest methane leak in U.S. history may not have been known if not for the niche specialty of Steve Conley, an affable 51-year-old pilot and an atmospheric scientist at UC Davis.
Conley’s arcane specialty is measuring leaks from gas and oil pipelines with sophisticated instruments installed on a single-engine, two-seat airplane that he flies. Most of the time, the work of such scientist-pilots goes unnoticed. But that all changed on Nov. 7 when Conley was contracted by the California Energy Commission to fly over the Aliso Canyon gas facility owned by Southern California Gas Co.
During that two-hour flight, while tracking atmospheric data in real time, Conley discovered the enormity of what he was measuring from an underground natural gas storage facility. “At first I thought my instruments were broken,” he said.
Using Conley’s measurements, the California Air Resources Board estimated the Aliso Canyon facility was releasing 44,000 kilograms of methane per hour, or the monthly equivalent of the greenhouse gases released by more than 200,000 cars.
Premium content for only $0.99
For the most comprehensive local coverage, subscribe today.
He’s completed five more flights since then and is helping to establish whether steps taken by Southern California Gas to stop the ongoing leak are helping.
To date, the environmental disaster has sickened and displaced thousands of residents in the affluent Porter Ranch neighborhood in northern Los Angeles. On Wednesday, Gov. Jerry Brown declared a state of emergency in the community.
“What Conley does gives us a very clear picture of what’s going on,” said Dave Clegern, spokesman for the California Air Resources Board. “Without him, we would not have any good overall numbers to post publicly.”
The board’s data show the methane releases are diminishing – to 30,300 kilograms per hour on Dec. 22. Still, it’s adding tons of greenhouse gases into the atmosphere, and much of Porter Ranch remains evacuated.
“Emissions of this is what we absolutely do not want to see,” said Clegern. “Methane is a powerful climate pollutant. ... We’ve not seen anything like this before and we have records on methane that go back 30 years.”
The Bee talked to Conley about the difficulty of his flights at Aliso Canyon and his advocacy for new responses to large and potentially catastrophic gas leaks.
Q: I understand you’re one of the only pilots in the country that measures methane releases?
A: There are maybe three or four aircraft like ours in the U.S. I’m the only one on the West Coast.
Q: Why are you such a rarity?
A: It is really expensive to outfit an airplane like mine. The analyzers on the plane run $300,000, and the plane itself runs $300,000. It takes a year of work to modify a plane like this according to (Federal Aviation Administration) permission. And then there is insurance.
Q: How difficult has it been to do these flights over Aliso Canyon?
A: These flights have been the hardest flights I’ve ever done, and I have 1,500 hours doing them. At Aliso Canyon there is a lot of turbulence at the site, and the methane smell is pretty bad. It’s so bad that every single person I’ve brought on six flights – every one has gotten sick. I feel it when I fly through the plume. It gives me a headache. But what really makes people sick is the turbulence.
Q: Is the turbulence from the leak?
A: No. It’s because of the way we have to fly in. We have Los Angeles airspace on one side and a mountain on the other. The winds that come over the mountains really start screwing around with the plane. We have to make pretty sharp turns at each side, so you’re feeling a lot of G force.
Q: What was your reaction to the numbers you were seeing on your first flight over the canyon?
A: I thought something was wrong with the instruments. I thought they had stopped working because I’d never seen measurement that large before.
Q: So you were not expecting anything significant?
A: No. We did not know if it would be a large measurement. It was a small mystery.
Q: It seems like your measuring this giant leak happened almost by happenstance?
A: Well, the California Energy Commission just happened to have a contract with me. If they hadn’t, no one would have known how big this was. We got lucky this time. That’s the reality.
Q: Some would say we have gotten really good at measuring and reacting to such leaks. True?
A: In a country that is so focused on climate issues, we do not have a rapid response plan for these kinds of things. We do not have anything in place to measure giant leaks like this, or to watch them to solve issues. The wellhead in Aliso Canyon is 61 years old. Is it a shock that it failed?
Q: What would solve that problem?
A: On a national level we need to have contracts ready where whoever can do this kind of measurement is ready to go. Where as soon as a leak is spotted you are given a go order and two hours later you’re measuring a leak.
Edward Ortiz: 916-321-1071, @edwardortiz