By Kris FitzPatrick, Staff Editor
Duke University researchers created a stir in the energy and environmental world last spring when their study on methane contamination of ground water near hydraulically fractured natural gas wells (pdf) was published in the National Academy of Sciences journal. The study found levels of methane in tested water from wells near “fracked” gas drilling sites to be 17 times higher than levels in water from other nearby wells. The group tested drinking water from 68 private wells in northeastern Pennsylvania. The methane also showed isotopic evidence of having originated deep underground. This finding contradicts some industry claims of methane contamination resulting from preexisting, natural methane seepage from sources nearer to the surface.
Shortly after the publication of their findings, the Duke researchers released a white paper detailing recommendations for hydraulic fracturing and shale gas extraction (pdf). The most fundamental recommendation is for states to rigorously test their ground water before and after hydraulic fracturing takes place. A major difficulty in proving or disproving contamination in previous cases has been the lack of a baseline sample for the water supply in question. The group also raises a federal policy issue, namely whether fracturing fluids should continue to be exempt from Safe Drinking Water Act regulations. This exemption was an informal one until 2005, when it was codified as part of the Energy Policy Act. A consequence of this exemption is that drilling companies are not required to disclose the chemicals that make up the fracturing fluids, making testing for these chemicals in ground water more difficult.
As lawmakers in several states, including North Carolina, debate legalizing hydraulic fracturing, let’s hope they carefully consider these recommendations. Shale gas offers the promise of jobs and economic gain, but protecting our drinking water must be the first priority.