Pavillion Area Concerned Citizens
Pavillion Area Concerned Citizens released this photo saying it shows a hydraulic fracturing drill site in the Pavillion/Muddy Ridge gas field. The group said it was taken from the porch of its chairman, John Fenton.
A controversial method of drilling for oil and natural gas appears to be the cause of groundwater pollution in a central Wyoming town, the U.S. Environmental Protection Agency said Thursday.
The EPA last month said it had found compounds associated with chemicals used in the drilling process known as hydraulic fracturing, or fracking, in the groundwater beneath Pavillion. Many residents say their well water has reeked of chemicals since the drilling began there and first complained to the EPA in 2008.
But until Thursday, the EPA said it could not speculate on where the contaminants came from.
In the draft report (.pdf) released Thursday, the EPA said that "the explanation best fitting the data ... is that constituents associated with hydraulic fracturing have been released into the Wind River drinking water aquifer."
Health officials had earlier advised residents not to drink their water after the EPA said it had found benzene and other hydrocarbons in wells it tested.
The process pumps pressurized water, sand and chemicals underground to open fissures and improve the flow of oil or gas.
The EPA emphasized that the findings are specific to the Pavillion area, noting that the specific type of fracking used there differed from fracking methods used elsewhere in regions with different geological characteristics.
The fracking occurred below the level of the drinking water aquifer and close to water wells, the EPA said. Elsewhere, drilling is more remote and fracking occurs much deeper than the level of groundwater that anybody would use.
The EPA is separately working on a national study of fracking.
Doug Hock, a spokesman for EnCana Corp., which owns rights to the Pavillion-area field, slammed the draft report. "The synthetic chemicals could just have easily come from contamination when the EPA did their sampling, or from how they constructed their monitoring wells."
Pavillion residents who organized to seek the tests welcomed the report.
"We are grateful to the EPA for listening to our concerns and acting on them," said John Fenton, chair of Pavillion Area Concerned Citizens.
Pavillion Area Concerned Citizens
Pavillion Area Concerned Citizens provided this photo of the home of John and Katherine Fenton. It said the haze was from fracking fluids vaporized in the drilling process and that it lasted for about 10 minutes. Similar releases happened a dozen times over 3 days, it added.
"This investigation proves the importance of having a federal agency that can protect people and the environment," added Fenton, whose home is across from one drill site. "We hope that answers to our on-going health problems and other impacts can now be addressed and that the responsible parties will finally be required to remediate the damages."
The industry contends that fracking is safe and its supporters were quick to blast the EPA.
"EPA's conclusions are not based on sound science but rather on political science," Sen. James Inhofe, R-Okla, said in a statement. "Its findings are premature, given that the agency has not gone through the necessary peer-review process, and there are still serious outstanding questions regarding EPA's data and methodology."
"This announcement is part of President Obama's war on fossil fuels and his determination to shut down natural gas production," added Inhofe, the senior Republican on the Senate Committee on Environment and Public Works.
Fracking has opened up areas that were previously considered too costly to drill. The most promising include the Marcellus Shale formation in the Northeast.
Development of the new shale deposits over the last few years has provided the United States with a century's worth of natural gas supply.
In Pennsylvania, production from the Marcellus has led to an energy boom that New York Gov. Andrew Cuomo is keen to replicate by lifting an existing moratorium on using the fracking process.
But hearings on that proposal have been contentious.
At the last hearing last month, protesters gathered in downtown Manhattan to express concern about the safety of water supplies, holding signs saying "Governor Cuomo, don't frack it up" and "Don't frack with New York."
"We have to be literally insane to contemplate fracking," state Sen. Tony Avella told reporters outside the hearings. "Wake up Governor Cuomo, this is not going to provide jobs or revenue, but what it will do is poison the water supply for 17 million New Yorkers."
This article includes reporting by msnbc.com's Miguel Llanos, The Associated Press and Reuters.
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