"Methane levels were 17 times higher in ground water near areas where shale-gas 'fracking' wells had been drilled in Pennsylvania, compared with areas where no gas drilling had occurred, a new study has found.
Duke University researchers analyzed methane gas in 68 private ground-water wells across five counties in Pennsylvania and New York. The study cited 'evidence for methane contamination of drinking water associated with shale-gas extraction.' ...
The peer-reviewed study, which is being published in the Proceedings of the National Academy of Sciences, is one of the first to conclude that hydraulic fracturing is polluting ground water. And it’s likely to be used as ammunition in court by those opposing drilling in sensitive watersheds.
The hydraulic fracturing approach has dramatically increased available US reserves of natural gas by unlocking gas that was previously trapped in shale formations from the mid-Atlantic to Texas to Colorado. But environmentalists and local residents have long claimed that fracking pollutes ground water with methane as well as with chemicals in the injection fluids."
Mark Clayton reports for the Christian Science Monitor May 9, 2011.