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development in the Piceance Basin. In addition, one of the operators is drilling (but not <br />fracturing) horizontal wells in the coal seams to take advantage of the anomalous natural <br />fracturing found at White River Dome field. In some areas of coalbed methane potential, <br />horizontal well technology may replace hydraulic fracturing as a method to enhance <br />coalbed methane well performance. <br />Within the Cameo Coal Zone, Barrett Resources typically used 3,000 to 3,500 barrels of <br />gelled 2% potassium chloride water with 273,000 to 437,000 pounds of sand over a <br />maximum 450 feet of the Cameo Coal Zone to stimulate coalbed methane wells <br />(Quarterly Review, 1993). It was shown that these hydraulic stimulations created short <br />(100- foot), multiple fractures around the wells (Quarterly Review, August 1993). Fuel <br />Resources Development Company used 3,000 to 10,000 barrels of gelled water and <br />200,000 to 1,300,000 pounds of sand to fracture their wells in the White River Dome <br />Field (Quarterly Review, 1993). All but one of Conquest Oil Company's wells was <br />hydraulically fractured with 1,500 barrels of water or cross - linked gel and 31,000 to <br />230,000 pounds of regular or resin - coated sand (Quarterly Review, 1993). <br />3.4 Summary <br />The Piceance Basin shows promise as a source for coalbed methane production based on <br />the estimated 80 to 136 Tcf of gas contained within the Cameo - Wheeler - Fairfield coal <br />zone (Tyler et al., 1998). However, overall low permeabilities as well as great depths to <br />coalbeds appear to have slowed coalbed methane development in the basin. <br />Nevertheless, a pilot program in White River Dome Field has had success in coalbed <br />methane production, attributable primarily to the extensive natural fracturing in the area. <br />As a result, operators are taking another look at coalbed methane development in this <br />basin. <br />Hydraulic fracturing is the common method used to extract coalbed methane. Drilling of <br />horizontal wells in the coal seams is a method that is being evaluated in the White River <br />Dome Field pilot project as an alternative to hydraulic fracturing. In some areas of <br />coalbed methane potential, horizontal well technology may replace hydraulic fracturing <br />as a method to enhance coalbed methane performance <br />The fluids used for fracturing vary from water with sand proppant to gelled water and <br />sand. Between 1,500 to more than 11,000 feet of strata separate the coals from the <br />shallow USDWs, indicating that the potential for water quality contamination from <br />hydraulic fracturing techniques is minimal. The only hydraulic fracturing fluid <br />contamination pathway to the USDWs might be through faults or fractures extending <br />between the deep coal layers and the shallow aquifers. The occurrence of these fractures <br />and faults has not been substantiated in any of the literature examined for this <br />investigation. <br />Evaluation of Impacts to Underground Sources <br />of Drinking Water by Hydraulic Fracturing of <br />Coalbed Methane Reservoirs <br />June 2004 <br />A3 -6 <br />