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1 <br />~y • • <br />includes an array of shallow piezometers used to model temporal and spatial changes in water- <br />table configuration and response to irrigation water inputs. <br />2.1.1 Mining and Reclamation Plan <br />Site access will be along a new road constructed specifically for this project. The construction <br />period is scheduled from early Summer though Fall of 1999 (Table 1). This road transects private <br />property owned by the Soaring Eagle Ranch and will intersect Colorado State Highway 340 <br />(Broadway) at the existing intersection of Broadway and South Broadway (Appendix B, MP-1 <br />and MP-2). A section of the tail water drainage ditch (part of undisturbed wetlands), an interior <br />wetland, and two sections of Monument Creek will need to be crossed to access the Processing <br />Site (Appendix B, MP-1 and MP-2). <br />Site access road crosses the tail water ditch and interior wetland in the far southwest comer of <br />site; interior wetland is located in the Processing Site area. The tail water ditch crossing, wetland <br />crossing, and two Monument Creek crossings (refer to Appendix B, DS-1 for crossing designs) <br />will disturb about 0.05 acres of wetlands. Wetland vegetation only occurs at the farthest north <br />Monument Creek crossing. Mitigation (Appendix B, W-2) involves placing excavated wetland <br />materials in a prepared constructed wetland bench adjacent to the disturbed area. Mitigation for <br />excavated wetlands in tail water ditch and interior wetland crossings will occur under Mitigation <br />Phase A. Livestock will be excluded from the mining and wetland mitigation areas until <br />vegetation becomes reestablished and the COE confirms that an acceptable mitigation goal has <br />been reached. <br />Phase I <br />Phase I Mining and Phase A wetland mitigation will proceed from September 1999 through <br />December 2000 (Table 1). Phase A is slated for the first 6 months and mitigates wetlands <br />excavated from the Phase I Mining and Processing Site areas. Topsoil and subsoil will be stripped <br />and stockpiled separately in the area for use in preparing a 200-foot wide and 350-foot long <br />wetland bench in the Phase I Mining area (Appendix B, W-1). The constructed wetland bench <br />(Appendix B, DS-2) will be backfilled, following removal of sand and gravel, using a subsoil base <br />capped with topsoil. Additional fill needed to raise and slope bench to required elevations will be <br />provided from stripped Phase I and Processing site areas being prepared for mining. Final <br />tonnage of gravel removed from these areas during this period is estimated at 280,000 tons. <br />Bench elevation needs to correspond to river groundwater elevation based on ordinary water level <br />of river to provide saturated soil conditions supportive of aself-sustaining wetland. Bench <br />elevations will target an elevation 2 feet below normal river levels of closest reach during ordinary <br />water stages as determined from several years of observing seasonal river flows. <br />2-2 <br />