An EPA report published Tuesday told residents near Pavillion, Wyoming to avoid drinking and cooking with well water after tests revealed petroleum hydrocarbons and other contaminants in 17 out of 19 wells near the town. Many residents worry that local drilling for natural gas is to blame. The EPA is still investigating.
“EPA has not reached any conclusions about how constituents of concern are occurring in domestic wells,” the report said. [Reuters]
As the agency continues its investigation, it along with other government organizations and the natural gas company EnCana, will provide alternative drinking water sources for affected residents. EnCana volunteered to provide the water, though a company representative told the AP that company’s tie to the contaminated the wells is unclear–since the chemicals appeared in earlier EPA tests, before EnCana’s drilling started in 2005.
For Pavillion, which has around 250 nearby gas drilling sites, the report adds to findings from earlier well tests taken in the spring of 2009.
In spring 2008, residents of Pavillion–concerned about the quality of their drinking water–contacted the EPA in Denver, Colorado. The agency sampled 39 individual wells (37 residential wells and two municipal wells) in March 2009 and found nitrate, arsenic and methane gas. The agency conducted the second sampling in January 2010. [CNN]
The news adds to concerns about natural gas companies’ hydraulic fracturing, commonly called fracking. Though individual gas companies use different drilling techniques for different geological structures, the basics involve drilling around 1,000 to 8,000 feet underground and pumping in 50,000 to 350,ooo gallons of water to crack the underlying rock. After removing 15 to 80 percent of that then-contaminated water, the gas company can pump out the natural gas which flows from the cracks. The water usually comes from local surface water or groundwater; once contaminated, it can go back to surface water if filtered or into a new well underground.
As 80beats discussed in June, some believe natural gas could soon satisfy a large proportion of the United States energy needs, an estimated (pdf) 20 percent by 2020. As a result, more people are demanding a better understanding of hydraulic fracturing’s effects on drinking water sources. The EPA plans to conduct an extensive, two-year study on hydraulic fracturing starting later this year.
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Image: flickr / AZAdam, EPA