The question of how much methane is leaking out of the country’s booming gas fields, compressors, storage tanks and pipelines has been controversial. The Environmental Protection Agency has relied on a relatively benign estimate of 1.4 percent. The Science study suggests that is far too low. Relying on extensive measurements on the ground and from the air, an army of researchers assembled direct observational data suggesting that the rate is more like 2.3 percent. The difference seems small, but if true it would cut drastically into natural gas’s climate advantage over coal. And there is some reason to believe their estimates might understate the problem, given that they did not closely examine leaky last-mile gas distribution networks.
The good news is that the problem would be easy to fix. The study suggests that the major problem may be with storage tanks, pipelines, seals and other infrastructure that is operating dramatically outside of normal conditions — in other words, obviously in need of repair. Even better, maintenance will often pay for itself or nearly so, as operators collect and sell more gas.