Methane found in water near fracking sites

WASHINGTON -- New research is providing some of the first evidence that a controversial gas drilling technique called fracking can contaminate drinking water.

The study published yesterday found potentially dangerous concentrations of methane gas in water from wells near drilling sites in northeastern Pennsylvania, although not in Central New York, where gas drilling is less extensive.

But in an unexpected finding, the team of Duke University scientists found no trace of the chemicals used in fracking in 68 wells tested in Pennsylvania and in Otsego County, N. Y.

In hydraulic fracturing, or fracking, water, sand and chemicals are injected underground to crack the rock and get natural gas to flow into a well. Critics of the technique have worried more about the chemicals because companies have refused to make public the proprietary blends used and some of the ingredients can be toxic.

On average, water from wells less than a mile from drilling sites had 17 times more methane than water tested in wells farther away, according to the study published yesterday in the Proceedings of the National Academy of Sciences.

Methane in small amounts is not known to be toxic, but in high concentrations it can be explosive and cause unconsciousness and even death, because it displaces oxygen needed to breathe.

In the most severe case, a homeowner in Bradford County, Pa., who leased her property to a gas company, has so much methane coming out of her tap she can light her water on fire. A natural gas well is 800 feet from her house. "Not every homeowner within a kilometer [ will have high methane concentrations," said Stephen Osborn, a postdoctoral associate at Duke University's Center on Global Change. "If you are a homeowner within a kilometer, and our study shows this, I would be a little bit concerned."What the study does not say is how exactly the methane is getting into drinking water sources, and what part of the drilling is potentially involved. While wells closer to drilling sites had more methane, most of the wells in the study -- 85 percent -- had some.