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(.:~• -~. Memo to Dave Berry Bowie No. 2 Geotech Study page 3 the information provided within this preliminary report, the morphology conclusion is unwarranted. The author references a major, recent rock slope failure which occurred just to the east of the proposed portal area. At other locations in the report the entire bedrock section is referred to as meta-stable. The slide in question occurred in the early 1980's in response to the bulldozing of several light access prospect drilling roads by Coors Energy while exploring the property. The effected bedrock section is clinkered by subcrop coal burn, resulting in typical deflation fracturing of the overlying bedrock. The application contains references to a general outcrop burn zone throughout the property anticipated to be up to 300 feet in width. I suspect that the anticipated portal bench cut of up to 80 feet in height could experience significant destabilization problems, unless the rock mass is retained. I suspect that this same problem might be encountered to varying degree in other cuts throughout the site. Page 7 The reports states; "Erosion potential is low to moderate across this site, due to steep slopes, thick to sparse vegetation and silty clay soils. Erosion potential may be expected to increase somewhat during construction, but should return to pre-construction rates, or less, if proper construction and grading practices are followed." Combined with many of the statements appearing later in the report, regarding the swell potential, plastic character of many of the soils, low angles of internal friction, and the extensive disturbance anticipated in developing the site this statement appears tenuous, at best. Page 8 The report states that three deeper borings were completed as inclinometers. The slope performance information developed by these inclinometers may be extremely important. Because of the magnitude of