Chemical compounds used to extract natural gas were found in three water samples from Pennsylvania’s Marcellus Shale region, according to a study published Monday in the Proceedings of the National Academy of Sciences.
The contamination occurred at three Bradford County households whose owners settled a lawsuit with Chesapeake Energy Corp. in 2012 after natural gas polluted their well water. The additional chemicals may have mixed with groundwater after a pit leak from a conventional well or when nearby drilling drove them toward the aquifer, according to the study.
“We’re not claiming that it’s from hydraulic fracturing,” Garth Llewellyn, a hydrogeologist at Appalachia Hydrogeologic & Environmental Consulting LLC, and the study’s lead author, said in a telephone interview Monday. “We’re not trying to make assertions where we shouldn’t be. We’re looking at all the possibilities.”
In hydraulic fracturing, water and chemicals are blasted into rock formations to extract oil and gas. Drillers, which last month decried the first U.S. regulations for fracking on federal land, have argued the practice is safe and, along with conventional gas extraction, doesn’t jeopardize groundwater supplies.
The contaminants in the water samples, including the chemical compound 2-Butoxyethanol, or 2-BE, were found in quantities that didn’t pose immediate health risks, Llewellyn said. Additional research is needed to determine exactly which chemicals were present and in what quantities they’re harmful.
“I really don’t care if it’s fracking or if it’s just drilling fluid -- if it’s hazardous, it’s hazardous to your health,” Llewellyn said. “That’s really what we’re trying to emphasize and make sure the general public understands -- to stop thinking just about hydraulic fracturing and more about the overall process of oil and gas development.”