Methane leaks across US pose a much greater threat than Aliso Canyon

Utah, Colorado and Texas are being aggressively pumped for oil and natural gas, producing methane leaks in quantities much higher than previously thought - and little is being done to contain the problem

When Stephen Conley, an atmospheric scientist and pilot, saw an emissions indicator skyrocket in his Mooney TLS prop plane, he knew he had found a significant methane leak. His gas-detecting Picarro analyzer indicated he was flying through a plume of gas escaping at 900kg per hour. The colorless, odorless gas was enough to cover a football field to a height of 20 feet in a single day. But this flight wasn't over the highly publicized Aliso Canyon in Los Angeles; Conley was circling the Bakken Shale, a rock formation in western North Dakota that has been aggressively pumped for oil and natural gas.

Day in and day out, small leaks in oil and gas producing regions like the Bakken Shale are emitting methane in quantities that collectively rival or even exceed Aliso Canyon. New figures released by the Environmental Protection Agency (EPA) last month indicate the potent greenhouse gas is being emitted from leaks across the US in quantities "much larger" than previously thought.