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4. We concur that the favorable attitudes of the dominant foliation jointing into the <br /> hillside is generally compatible with the originally proposed 1:2 (H:V)slope ratio. <br /> Additional discussion about slope stability and proposed steepened slopes is <br /> included in the slope stability section below. <br /> Finally,the Geologic Map of Colorado,(1'.500,000) indicates two northwesterly faults <br /> transecting or passing just southwest of the site. These faults would be considered <br /> inactive and cut across the both the Precambrian metamorphic rocks that occur <br /> southeast of U.S. 285 and the slightly younger granitic rocks(Silver Plume Quartz <br /> Monzonite and Pikes Peak Granite)that occur northwest of the highway. <br /> B. Site Topography(G.1.b) <br /> The site location and topography are discussed in detail in the attached Fox report <br /> submitted as part of the original DMG permitting and those details are not repeated <br /> herein. Additional comments about site topography for the present rezoning effort <br /> include the following: <br /> 1. Pre-mining slopes at the site were closer to approximately 2:1 than 2.5:1 <br /> as reported in the Fox report. <br /> 2. The cut slope along the west side of U.S. 285 across the highway from the <br /> quarry is approximately 1:1 overall,and steeper in the lower cut face. <br /> 3. Historic mined and reclaimed slopes by others at the site are as steep as <br /> 1:2 and appear to be generally stable. <br /> A site topographic map was included in the original DMG permit application. This <br /> map is included as Attachment A to this report. The Geologic Map prepared for this <br /> report and included in Attachment B also shows the pre-mining topography. In <br /> addition,Elk Creek has developed a very detailed site topographic map prepared by <br /> Falcon Surveying,Inc.based on a June 2,2004 field survey. A copy of the new <br /> detailed topographic map showing existing conditions (1 in.=40 ft; 1 ft contour <br /> interval)is provided elsewhere in the rezoning submittal. <br /> C. Test Borings or Core Samples (G.I.c.) <br /> No test borings were performed and no core samples were obtained as part of original <br /> site permitting efforts. Since that time quarry development has occurred and there are <br /> ample bedrock exposures at the site to preclude the need for test drilling to identify <br /> site lithologies. Topsoil and overburden thicknesses are negligible,varying from less <br /> . than a foot to approximately 3 ft thick. There is an upper weathered bedrock zone in <br /> which moderately severely weathered to completely weathered bedrock extends <br /> approximately I5 to 20 ft into the rock mass. Bedrock exposures at the site haye been <br /> mapped for geologic structure and these data are included in the slope stability <br /> section below. <br /> JC 0077? <br /> Peterson/Elk Creek <br />