Gas Drilling May Be Leaking Twice as Much Gas as Previously Thought, Study Finds By Nicholas Kusnetz

Research suggests that emissions of methane, a greenhouse gas 20 times more potent than CO2, far exceed current estimates for gas drilling and production.

                   

Weeks after Barack Obama promoted natural gas as a key part of U.S. energy policy in his State of the Union address, new research says gas drilling may be emitting far more methane and other pollutants into the atmosphere than current estimates suggest.

The work, performed by scientists with the National Oceanic and Atmospheric Administration, focused on Weld County, Colo., home to more than 20,000 gas wells. After years of monitoring and study, the researchers estimated that about 4 percent of the methane produced by these wells is lost to the atmosphere.

That's about twice as much as current estimates would suggest, and twice what the EPA assumes is lost nationally during gas drilling and production, said Gabrielle Petron, a lead author of the study.

"What I've learned in the past three or four years is that there's a lot we don't know, and the industry may not be aware of these leaks and how important they are," Petron, a researcher with NOAA and the University of Colorado, told InsideClimate News. "Until you go out there in the field and take measurements you may not have a sense of what is leaking and how much it's leaking."

Methane accounts for about 10 percent of greenhouse gas emissions nationwide. Leaks during the drilling, production and transmission of natural gas are the largest source, accounting for about a third of all man-made methane emissions.

In addition to methane, the researchers also found surprisingly high emissions of benzene, a carcinogen, and other pollutants.

Petron said the study, which is being published by the Journal of Geophysical Research, is the first to take atmospheric measurements of emissions from gas drilling. Current estimates are based primarily on isolated sampling and data provided by drilling companies, she said. States and the EPA use that data to build models for extrapolating emissions.

Advocates have been pushing the industry for years to capture more of the gases that leak during drilling and production. Jeremy Nichols, director of the climate and energy program at WildEarth Guardians, a New Mexico-based environmental group, said gas companies shouldn't wait for more studies to begin reducing emissions.