Drinking water 'safe from fracking' GAS: A landmark study in the US on hydraulic fracturing, or fracking, shows no evidence that chemicals from the natural gas drilling process moved up to contaminate drinking water aquifers at a western Pennsylvania drilling site. Researchers for the US Department of Energy, after a year of monitoring, found the chemical-laced fluids used to free gas trapped deep below the surface stayed "thousands of feet" below the shallower areas that supply drinking water.