The EPA launched yesterday a two-year, $1.9 million study to determine whether hydraulic fracturing, the oil- and gas-production technique used in Pennsylvania's Marcellus Shale region, is a danger to groundwater supplies.
"The study will be conducted through a transparent, peer-reviewed process, with significant stakeholder input," said Paul T. Anastas of the EPA's Office of Research and Development.
The process, called "fracking," involves injecting water and chemicals into wells under high pressure to break up the source rock to unlock oil and natural gas. Along with horizontal-drilling technology, it has transformed formerly uneconomical drilling sites into lucrative ones.
But environmentalists have expressed fears that fracking could contaminate groundwater. The oil and gas industry says it has employed the process on hundreds of thousands of wells for decades without fouling any aquifers.