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Introduction <br />The following report presents the results of a slope stability analysis for a proposed <br />open cut gravel extraction operations at the Varra Great Western Sugar site near <br />Greeley, Colorado. This analysis was performed at the request of Varra Companies. <br />Background Information <br />The proposed Great Western Sugar Property gravel quarry occupies the North half of <br />Section 9, Township 5 North, Range 65 West of the 6th Principal Meridian. The <br />surrounding land use consists of agricultural, rural residential, commercial and open-cut <br />gravel quarry operations. The proposed mine area occupies an estimated 130 acres. The <br />water table at the site is located in unconsolidated alluvial deposits associated with the <br />Cache La Poudre River. <br />Information provided by current mining operations document soil conditions generally <br />consisting of two to 12 feet of fill, silty sand and lean clay, which are underlain by sand and <br />gravel deposits, which in turn are underlain by Pierre Shale. Over the entire area the <br />range of saturated thickness of the sand and gravel deposits (prior to mining) is estimated <br />at 25 to 70 feet. It is our understanding that the sand and gravel will be dewatered during <br />aggregate extraction at a maximum depth of 45 feet. Any extraction beneath 45 feet will <br />be wet mining. <br />The water table in the vicinity of the four proposed quarry locations will be drawn down to <br />35 feet below ground surface or to the Pierre Shale, whichever occurs first. The mine will <br />be dewatered by allowing groundwater to flow from the side walls of the excavation into <br />ditches. It is our understanding that the water will be pumped into unlined ponds east of <br />the mine and will eventually make its way into the Cache La Poudre River. Site Conditions <br />are depicted in Appendix A.