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• INTRODUCTION <br />Merrick 6c Company, as part of the Phase 2 Geotechnical Studies, has been <br />contracted by Colorado Westmoreland, Inc. to evaluate the impacts of surface <br />drainage on the stability of slopes at the Orchard Valley Mine site. Geo-Hydro <br />Consulting, Inc. in their "Report, Phase 2 Geotechnical Studies, Orchard Valley <br />Coal Mine, Paonia, Colorado, Colorado Westmoreland, Inc." indicate that many of <br />the slopes at the site are presently marginally stable. In order to obtain an <br />improved factor of safety, surface drainage must be controlled to insure that the <br />existing and proposed fills are not saturated by surface water runoff. <br />We have evaluated the drainage characteristics of all significant fills and have <br />made specific recommendations in order to minimize the likelyhood of saturation <br />of these fills. These recommendations include modifications to the existing <br />drainage facilities, installation of new drainage facilities and suggested main- <br />tenance of critical ditches and pipes. <br />Our recommendations are presented in three parts, each addressing specific faci- <br />lities. The first, and the most critical at this time, deals with drainage problems <br />associated with the existing facilities at the Orchard Valley Mine. The second <br />part addresses drainage related to a proposed waste rock pile. The final part is a <br />set of preliminary guidelines to control drainage for the ultimate reclaimed <br />configuration. <br />We have also included a Part 4 in this report which presents the results of an <br />investigation of the foundations on the crushing and screening fill level. <br />~. <br />