A new study from Duke University experts, published in the Proceedings of the National Academy of Sciences, discusses the results of an investigation of 141 drinking water samples taken from private water wells in Pennsylvania. The scientists found that: "on average, methane concentrations were six times higher and ethane concentrations were 23 times higher at homes within a kilometer of a shale gas well. Propane was detected in 10 samples, all of them from homes within a kilometer of drilling."
A Duke scientist concluded the data: "all suggest that drilling has affected some homeowners’ water."
I still regularly hear industry defenders state that *all* methane found in groundwater is naturally occurring. While it is true that *some* methane found in groundwater is naturally occuring, it is also true that some is not. For years state regulators have been finding oil and gas companies responsible for causing methane contamination of drinking water. These are facts that cannot be denied.
Back to the Duke study--my colleague Dan Raichel blogged on the details if you'd like to know more.