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<br /> <br />EXHIBIT G <br />ff~TER INFORMATION <br />Intro ic~uction <br />The Swan River Resource site is located in the Swan River basin. <br />The property is located in the valley created by the river. The <br />proposed operation will not impact the surrounding surface water or <br />groundwater and will not injure surrounding property owners. <br />The operator proposes to excavate the top layer of dredged tailings <br />from the are surrounded by the Swan River. The operation will not <br />impact groundwater or surface water, since the mining will stay <br />about five feet above the bottom of the river channel. In the <br />alluvial material adjacent to the river, the water table elevation <br />is assumed to be the same elevation as the river. <br />' Surface water <br />The swan River discharges runoff from an unaged basin in the <br />mountainous region of Summit County. The nearest USGS stream gages <br />are located on the Blue River at Blue River, Colorado (#09046490- <br />upstream of the Swan River) and near Dillon, Colorado (#0904660-at <br />the Swan River outfall). The 100-year peak discharge and 100-year <br />flood depth for the upper basin was calculated for the Swan River <br />at the downstream property boundary. The values for the unaged <br />basin were calculated by regression equations developed from gaged <br />stations in adjacent areas. The equations for ungaged streams were <br />reported in Colorado Water Conservation Board, Colorado Department <br />~ Natural Rgsources, Technical Manual No. 1, Manual for estimating <br />flood char~teristics of Natural-Flow streams in Colorado, 1976. <br />The upper basin area was delineated on 7.5 minute USGS topographic <br />maps. The basin was planimetered to determine the watershed <br />covered 27.4 square miles (A). The average precipitation at the <br />nearest gaging station (#0904660 with a basin area of 119 square <br />milesl was recorded as 28 inches (p) over a 16 year period, and <br />this value was adopted for the ungaged Swan River basin. The <br />ungaged basin was less than 50$ of the size of the gaged basin near <br />Dillon; therefore, the equations for ungaged basins were used. The <br />equations and values for the upper basin are as follows: <br />Q ,oo = 1.88 A o.~~~ p o.v~: = 568 cfs (range of error +458,-318) <br />D ,oo = ] 99 A o.:s, p o.osr = 3.26 feet (range of error +32$,-24$) (the <br />depth of the 100-year flood is measured above the normal flow). <br /> <br />G-1 <br />