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. ' " JAfI(0 7 2Q08 <br />Division ai Rec;amation, <br />A~;infig anc 1 afety <br />I~EHN•5I ion Kehn <br />~~~.,~,„, Construction Inc. <br />Asphalt Pawng • Crushed Aggregates • Earth GENERAL CONTRACTORS <br />moNng • Truclung • Underground lllifilies • Rotaau'0vtg <br />TiTnnath Pit <br />Don Kehn Construction currerrtly holds a 404 perriTit from the U.S. Corps of Engineers (copy attached) <br />enabling mining of gravel at its Timnath Pit. The mining is to be performed in Phases per the pemrit with <br />listed time durations. <br />The mining plan provides for concurrent mitigation of the 78.4 acres of wetland existing on the site that <br />will be impacted by mining. At no time, throughout the lift of the project, will there be less than 75 <br />percert of the total original wetlands quantity on the site, which is 63.8 acres. During each mining Phase, <br />different proportions of the 63.8 acres will be temporary and permanent <br />The overall mitigation plan is to create a total of 144.4 acres of permanent wetlands and open water per a <br />schedule for each phase. The plans call for a maximum 12-inch layer of wetland topsoil to be excavated <br />from all impacted wetland areas and stockpiles separately for placement in a minimum 4-inch layer in <br />wetland mitigation areas. For permanent wetland mitigation, wetland soil placement will be <br />supplemented with plantings. <br />Paramount to wetland construction is proper elevation to achieve areas that will remain moist naturally <br />without constant water level manipulation. if the grade is too high it will be dry and thus not wetlands. TF <br />the grade is too low it will be flooded by natural groundwater caused by the effect of the nearby Poudre <br />River. Although some deep water areas are acceptable in varying degrees by the Corp, the moist <br />desirable wethmd is wet meadow and most difficult to achieve. Wet meadow is generally saturated with <br />up to six-inches standing water. <br />The elevation issue stems from the differential of pits mined of gravel to their being backfilled and plated <br />with wetland topsoil To achieve this balance. of fill, deep water areas must be excavated far into the <br />underlying shale at considerable expense in order to generate the material to create proper grade. <br />According to a recent bimonthly monitoring report from. our enviroamemal cottzultant, Savage and <br />Savage F.nviroffirenial; report dated 4/15/07, we are crurentty deficient in wetland creation as follows: <br />Accepted wetlands: <br />Shallow water 3.64 acres <br />Open water 10.65 acres <br />Wet meadow 11.47 acres <br />25.76 acres 25.76 acres <br />Developing wetlands (built bnt not accepted): <br />Shallow water 14.38 acres <br />Wet meadow 27.44 acres <br />51.82 acres 51.82 acres <br />All constructed to date 77.58 acres <br />Wetlands required 144.4 acres <br />Wetlands remaining to be constructed 66.82 acres <br />6550 So. County Road 5 • Fort Collins, Colorado 80528 • Phone (970) 226-4111 • FAX (970) 22fi-4115 <br />807 Murray Road • Cheyenne, Wyoming 82007 • Phone (307) 632-4~0 • FAX (307) 632-0016 <br />