That means addressing the presence of methane and hazardous chemicals in bodies of water adjacent to drilling operations and in underground sources of drinking water nearby, which has been reported anecdotally.  A report released by Riverkeeper last year pointed to numerous surface water spills, including 4,200 gallons of frack fluid that seeped into a wetlands area in Bradford County, PA, and to chemical leaks, like the one that caused a measurement of 50 times the legal amount of a carcinogenic substance in a private well in Midland, TX.
     Whatever benefits natural gas is able to offer (and some are significant), they are surely not worth the alarming cases of contamination reported to state environmental protection officials, including discolored tap water and the evidence of methane leaking into the air from drill sites.  By congressional mandate, the EPA is currently conducting a review of the effects of shale gas drilling on water quality after years during which the business has been allowed to expand while little was known about it and little has existed in the way of oversight.
     Drilling companies were given significant exemptions from environmental regulations under the 2005 Energy Policy Act, including the right not to identify the chemicals they use.  Government disclosures released since then show the use of twenty-nine known or suspected carcinogens among the hundreds of chemicals in frack fluid, including the BTEX compounds benzene, toluene, ethylbenzene, and xylene, which invites questions about the strength and enforcement of clean water provisions going forward.