Coalbed methane development in the Powder River basin has a long history that is largely reflective of the uncertainty of the economics of the play, caused by a poor understanding of the reservoir. Conventional wisdom characterized the Wyodak and related coals as too shallow and too immature, having too much water and too little gas. Prior to 1986, gas shows in the Wyodak were encountered by ranchers, and water well drillers, and recorded by researchers. In 1986, conventional gas sands charged with CBM from the adjacent Wyodak coal were discovered and produced. In 1989, the relatively deep Big George coal was drilled in the Sasquatch Unit of Johnson County, without success. Rahwide Butte commenced production, with some success. Tax credits spurred continuous drilling of a limited number of CBM wells through 1992, many of which did not come on line until 1993. The Marquiss wells that started producing in 1993 became the first significant producers that began to indicate economic reserves and production rates. In 1994 the Macsy area came on line and added further credibility to the play. By 1997, sustainable production rates and apparent significant reserves caused and drilling of the play to increase significantly. During this long development period, a great deal was learned of the characteristics of the reservoir, the environmental and political aspects of operations, costs, and technical aspects. The economic limits of the play remain uncertain in areas where the Wyodak and Big George coals are deep, where hydrologic conditions differ from the "sweet spots", and where splitting of the coal causes difficulty in completions.

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