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:~~ ~, <br />A AGAPTTO ASSOCIATES, INC. <br />Mining & Civil Engineers & Geologists <br />1726 COLE BOULEVARD <br />BUILDING 22, SURE t3~ <br />GOLDEN, CO 80401 <br />USA <br />VOICE 303.271.3750 <br />www.agapao.can <br />CORPORATE HEADQUARTERS <br />GRAND JUNCTION <br />970.242.4220 <br />CHICAGO OFFICE <br />630.792.1520 <br />July 6, 2006 <br />Mr. Jim Mattern <br />Trapper Mining, Inc. <br />P. O. Box 187 <br />Craig, CO 81626 <br />53415 <br />Re: Proposed Deal Gulch Impoundment Dam-Preliminary Slope Stability <br />Analysis <br />Deaz Jim, <br />This letter report details the resuhs of the preliminary slope stability analysis performed <br />on the Deal Gulch drainage impoundment dam Included in this report is a description of the <br />expected soil properties around the proposed impoundmem area and resuhs of slope stability <br />analysis of the embankment. <br />The scope of work for this project involved (1) review of laboratory testing performed in <br />August 2000 for soil characterization, (2) site reconnaissance to examine current condition of the <br />dam site, and (3) performing a two-dimensional (2D) analysis of a section of the embankment to <br />assess slope stability. This report includes a description of the existing site, a summary of <br />expected soil conditions and properties, a description of the analysis and summary of resuhs, and <br />recommendations for construction verification. This report is imended to be included with the <br />permit application for construction of the embankment. <br />SITE CONDITIONS <br />A site visit to the proposed impoundment dam site was made on June 28, 2006. The site <br />is located in Deal Gulch about 0.6 miles south of the crest of the hill nearest the G-Pit mining <br />azea on the Trapper Mine property (Photo 1). A rock outcrop of the Twenty Mile Sandstone <br />Formation is the most notable geologic landmark neazest the dam site, which is located about <br />750 ft upstream of the proposed impoundment dam (Photo 2). <br />The proposed impoundment pond azea is currently a gently sloping grassy meadow. The <br />meadow has been used as a cow pasture. The drainage azea splits upstream to the east and west <br />of the Twenty Mile Sandstone outcrop, but is fed mainly by the east side of the gulch. There is a <br />small impoundment dam about 500 ft upstream of the proposed impoundment. Downstream of <br />the dam, the gulch narrows (Photo 3). There is a similar drainage impoundment dam about <br />GEOENGINEERING • MINING ENGINEERING • CIYIL ENGINEERING <br />