Friday, July 19, 2013

Federal study done with company OK finds fracking chemicals didn't contaminate aquifers at one site

"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 aquifers at a western Pennsylvania drilling site," Kevin Begos reports for The Associated Press. "Researchers found that the chemical-laced fluids used to free gas trapped deep below the surface stayed thousands of feet below the shallower areas that supply drinking water." It was the first time a drilling company had allowed government scientists to conduct such an experiment.

Researchers monitored the site for a year, using drilling fluids tagged with markers that were injected more than 8,000 feet below the surface, but were not detected in a monitoring zone 3,000 feet higher, Begos reports. "That means the potentially dangerous substances stayed about a mile away from drinking water supplies."

During the study "eight new Marcellus Shale horizontal wells were monitored seismically and one was injected with four different man-made tracers at different stages of the fracking process, which involves setting off small explosions to break the rock apart," Begos reports. "The scientists also monitored a separate series of older gas wells that are about 3,000 feet above the Marcellus to see if the fracking fluid reached up to them." Most gas wells are more than a mile underground, while drinking water aquifers are usually 500 to 1,000 feet below the surface. (Read more)

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