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limited to the following: OGCC website, databases, and library; DWR maps, publications and data bases; <br />USGS maps, reports and other publications; Colorado Geological Survey maps and publications; Bureau <br />of Land Management maps and publications; and Colorado Department of Public Health and <br />Environment data. Similar studies of stream depletions from CBM production have been completed for <br />the Piceance, San Juan, and Raton Basins (see http•//eeosurvey.state.co.us/Default.asnx?tabid=488 ). <br />Content and approach from these other studies may be instructive for the present study. It is likely that <br />other useful information will be available from other sources, but those listed herein are considered as <br />being most applicable and are expected to significantly reduce the amount of additional data development <br />necessary to conduct the needed analyses. As part of the work on this project, the data sufficiency and <br />quality and the need, if any, for additional data to effectively carry out the study will be clearly assessed <br />and described. <br />At this time, an analysis of a two-phase (i.e., gas and water) system will not be considered. Depending <br />on the results of this study, it may be recommended that an additional study be performed using atwo- <br />phase model. <br />Methodology <br />The depletion determination methodology applied to these analyses will be the analytical "Glover' <br />methodology available in several formats. While it is recognized that the Glover methodology was <br />developed for alluvial applications, it is considered to be the most easily applied tool for the level of study <br />contemplated. The IDS "AWAS" program developed by Colorado State University is one acceptable tool <br />for this analysis. If the hydrogeologic setting is appropriate, the methodology developed by S.S. <br />Papadopulos and Associates for the DNR study, "Coalbed Methane Stream Depletion Assessment Study <br />-Northern San Juan Basin, Colorado" may also be useful. The report generated for this study will <br />include a discussion of the assumptions and limitations of the Glover methodology and the applicable <br />programs as applied to the determinations that are the subject of this study. A comparison of these <br />assumptions and limitations to the actual conditions and geometries encountered will be required. <br />Scope Details <br />This section of the scope details the analyses that will be required for the Sand Wash Basin in Colorado. <br />The study report will document the analysis, presenting the data utilized, the limitations of such data, if <br />any, the methodologies applied, the results, and a thorough discussion of any problems or issues <br />encountered during the analysis that would have a bearing on the outcome of the analysis. <br />The analysis will include as a minimum the following tasks. <br />1. CBM Gas Production and Associated Water Production <br />The levels of CBM production will be researched and assessed. As CBM production in the Sand <br />Wash Basin is in the early stages of development analogies may need to be drawn for other <br />basins where CBM development is more mature. This will include the following specific aspects: <br />1. Current Levels <br />a. Gas and Water Production <br />b. Development of Correlations between Gas and Water Production <br />2. Estimated Future Production Levels <br />a. Recent Production Trends and Projections <br />3. Well Densities and Distribution <br />2 <br />