Study finds fracking chemicals didn't spread

(AP)—A landmark federal study on hydraulic fracturing, or fracking, shows no evidence that chemicals from the natural gas drilling process moved up to contaminate drinking water at a western Pennsylvania drilling site, the Department of Energy tells The Associated Press.

After a year of monitoring, the researchers found that the chemical-laced fluids stayed thousands of feet below the shallower areas that supply drinking water, geologist Richard Hammack says.

The results are preliminary, but a scientist not involved with the study calls it an important way to monitor fracking. But Duke University scientist Rob Jackson cautions that the single study doesn't prove that fracking can't pollute, since geology and industry practices vary widely.

Kathryn Klaber, the CEO of the industry-led Marcellus Shale Coalition, calls the study "great news."

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