Two Studies Highlight Risks of Fracking-Released Methane

Two new studies highlight issues with methane gas emissions in hydraulic fracturing, or fracking, as the Environmental Protection Agency debates new regulations for the gas in an effort to combat global climate change.

One, published in the journal Energy Science and Engineering, suggests that the EPA has been miscalculating the nation's greenhouse gas footprint as a whole because the methane released during shale gas extraction has not been properly measured.

In 2013, the organization estimated methane from natural gas extraction to be 6 petagrams. But using a different modeling system, scientists from Cornell University say the true level is closer to 9.5 petagrams annually, or perhaps even higher.

(VIDEO: Fracking the Eagle Ford Shale)

“The EPA has seriously underestimated the importance of methane emissions in general – and from shale gas in particular,”Robert Howarth, who authored the paper and is a professor at Cornell University, said in a press release. “As a result, the federal government has been stating that total greenhouse gas emissions from energy use in the U.S. have been steadily declining since 2008.” But the federal estimates mihttp://www.weather.com/science/environment/news/studies-highlight-risks-of-methane-from-fracking

ght not tell the whole story, Howarth said.

Another new study, published in Water Resources Research, also suggests hidden issues regarding methane and fracking. The paper suggests that abandoned oil and has wells near fracking sites can become conduits for methane, which is then not currently measured by the current monitoring system. These wells, rather than hold and trap the methane gas, then release it to the surface where it can linger for a decade or more, warming the atmosphere at a level 100 times higher than carbon dioxide (though CO2 lingers in the atmosphere for much longer).

The new paper examined an area in New York, the Marcellus Shale formation, which contains more than 30,000 wells that date as far back at the 1880s. A mathematical model was applied to map the probability that new fracking features in the Marcellus would connect to a previously used oil and gas setup and that that well would be damaged enough to let methane seep in. The probability was found to be between .03 and 3 percent — before new industry-released data increased “the probabilities cited in the paper by a factor of 10 or more,” according to a press release.

Ultimately, the work raises concerns about this largely overlooked pathway for methane emission. "The debate over the new EPA rules needs to take into account the system that fracking operations are frequently part of, which includes a network of abandoned wells that can effectively pipeline methane to the surface," said the new paper's lead author, James Montague, an environmental engineering doctoral student at the University of Vermont, said