Workers tend to a well head during a hydraulic fracturing operation at an Encana Oil & Gas (USA) gas well outside Rifle, in western Colorado.
Workers tend to a well head during a hydraulic fracturing operation at an Encana Oil & Gas (USA) gas well outside Rifle, in western Colorado. Brennan Linsley AP
Workers tend to a well head during a hydraulic fracturing operation at an Encana Oil & Gas (USA) gas well outside Rifle, in western Colorado. Brennan Linsley AP