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1.0 INTRODUCTION <br />The Bowie Mine No. 2 is a subsurface coal mine owned and operated by Bowie Resources, LLC <br />(Bowie). The Bowie Mine No. 2 is located north of Colorado State Highway 133, approximately <br />3.5 miles northeast of Paonia, Colorado. The mine produces approximately 5 million tons of <br />coal per year. Coal waste from the wash plant as well as some high ash coal is currently <br />disposed of at a coal waste disposal area located immediately north of Colorado State Highway <br />133. <br />Buckhorn Geotech, Inc. ( Buckhorn) was retained by Bowie to evaluate stability of a proposed <br />new coal wastepile ( "gob pile ") site under consideration for use once the current wastepile has <br />reached its capacity. The new gob pile site is located between the Fire Mountain Canal and <br />Highway 133 and is roughly 1/3 mile southwest of the existing gob pile. We are pleased to <br />present this report summarizing our stability evaluation. <br />1.1 Scope of Services <br />Buckhorn conducted a stability evaluation of a proposed new gob pile site. The proposed site is <br />located south of the Fire Mountain Canal and north of Highway 133. Geometry of the proposed <br />gob pile, including slopes, benches, and wastepile heights, were provided by J.E. Stover and <br />Associates. Characterization of coal waste material, particularly shear strength, is based on <br />previous triaxial testing on "un- disturbed" and remolded gob as described in Buckhorn (2006). <br />Buckhorn did not conduct any subsurface investigation of the foundation materials for this <br />evaluation. Subsurface conditions and foundation strengths were assumed based on drilling and <br />testing conducted by Lambert and Associates (2001) along the railway south of the proposed <br />site, previous drilling and testing at the existing gob pile foundation conducted by Lambert and <br />Associates (2003), and geologic mapping in the area. As such, a subsurface investigation must <br />be conducted to characterize the subsurface foundation conditions at the proposed gob pile site <br />and verify assumptions made for this evaluation. This investigation may include index and shear <br />strength testing, and in -situ permeability testing. Additionally, we recommend on -going shear <br />strength and in -situ moisture /density testing of the gob materials. <br />2.0 SITE DESCRIPTION <br />The proposed new coal wastepile is located north of State Highway 133 and south of the Fire <br />Mountain Canal, as indicated on Drawing 1. The proposed new site is located approximately 1/3 <br />mile southwest of the existing gob wastepile. The wastepile footprint is approximately <br />1,350 feet long and 600 feet wide. The area of the footprint is approximately 15 acres and the <br />ultimate capacity of the wastepile is approximately 600,000 to 700,000 cubic yards. <br />The proposed site is currently occupied by an orchard. Other than fruit trees, the site is vegetated <br />with native grasses and shrubs. The existing ground surface slopes approximately 10% down to <br />Bowie No 2 South Gob Pile preliminary stability evaluation <br />Project #05- 126- GEO -08 <br />Page 4 of 10 <br />