A new study on a tiny town in Wyoming in America's west for the first time shows the impact that fracking has on drinking water supplies.  Fracking is the short name for Hydraulic Fracturing", the energy industry's practice of shooting chemical-laden water into underground rock to free trapped gas.

The study finds that fracking operations near Pavillion, population 221, have had clear impact to underground sources of drinking water.  Unsafe practices resulted in the dumping of drilling and production fluids containing diesel fuel, high chemical concentrations in unlined pits and a lack of adequate cement barriers to protect groundwater.  Drilling companies use proprietary blends that can include potentially dangerous chemicals such as benzene and xylene.  The Federal Agency for Toxic Substances and Disease Registry has advised area residents to avoid bathing, cooking or drinking with water from their taps.

"This is a wake-up call," said lead author Dominic DiGiulio, a visiting scholar at Stanford School of Earth, Energy & Environmental Sciences.  "It's perfectly legal to inject stimulation fluids into underground drinking water resources.  This may be causing widespread impacts on drinking water resources."

An earlier report from the US Environmental Protection Agency linked shallow fracking to toxic compounds in aquifers.  But it was met with heavy criticism from the drilling industry as well as state oil and gas regulators, and the EPA never finalized the findings.  A follow-up by the state of Wyoming also resulted in a series of reports without firm conclusions

The new Stanford study goes a step beyond the 2011 EPA report to document not only the occurrence of fracking chemicals in underground sources of drinking water but also their impact on that water that is making it unsafe for use.  And if the water could be fouled could happen in Pavillion, it could happen anywhere.

"Geologic and groundwater conditions at Pavillion are not unique in the Rocky Mountain region," said Dr. DiGiulio. "This suggests there may be widespread impact to underground sources of drinking water as a result of unconventional oil and gas extraction."