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<br />Tailings Impoundment Area <br />On August 28, 1994, the sits waa visited by representatives from Mice Safety <br />and Health Administration at C.O.M., Inc.'s request. There were satisfied that <br />the tailings impoundment was installed correctly, a copy of their opinion will be <br />forwarded to division under a separate ccver. <br />C.O.M., Inc. at one time considered raining the tailings impoundment area, <br />however ae an alternate to that, C.O.M., Inc. intends to remove 90% of the <br />materials from the tailings unpoundment area which will allow an 12 inch tree <br />board to exist in the tailings impoundment area. The tailings impoundment <br />area will not be used for disposal purposes but only for a holding facility for <br />materials that will be shipped to our brick making facility. <br />ills area northeast of the ruiilaite waa selected for the rnnatruction of the im- <br />poundment dam to contain the tailings that are produced by the milling ptv- <br />ceea i nee lldap A). 'I-ne site selected for the location of the tailings pond is on <br />property owned by C.O.;vi. Inc.."u~ ada4aatz storage capacity waa developed <br />on this site for a minimum of four years of milling operations at the an*acipated <br />rate of milling activity. The topography of ihia site is suitable for the conatruc- <br />fion and maintenance of a hillside tailings pond, kith gentle oper. slopes. The <br />anbattrtace conditinna ware ideal for cnnatnicting a atahle emhankrnent and <br />safely containing the tail; Aga t1~at were produced. 'Ihe entire area is one of low <br />seismic activity, and there is )d±±le risk to the tailings pond embanl~ent from <br />earthquake activity in flue location. the terrain above fire proposed tailings <br />pond that could provide a precipitation catchment area is limited, and there are <br />no streams above er directly below this site. <br />The tailings pond site is situated on 2.125 acres of land that ie encompassed by <br />the boundaries of the Oscar and Hetrtiles patented lode mining claims. A small <br />portaon of intervening laud is covered by the JoAnne unpatented lode mining <br />claim. <br />Topographically, the tailings impoundment area can be characterised as gently <br />eloping terrain. The present slope gradient of the ground that was selected <br />varies from 16 percent on the northeastern edge of the site to 14 percent on <br />the southwestern edge. The absence of even an intermittent stream channel <br />through this area makes this site a suitable one for the conetntction of a hill- <br />side tailings dam. <br />A very important factor m the selection of this location for tailrngs retention <br />was the hydrological investigation, which focused on the precipitation, ground <br />water, and potential water nenoff inflow. Based upon historical stream flow <br />records, the U.S. Geological Survey has calculated tnat 42 percent of the <br />annual precipitatica in Boulder County's mosatain region flews t0 the plains <br />each year. Because of the limited storage rapacity of'the mountain region's <br />crystalline rocks, a further v5 percent of the annual precipitation is returned to <br />~~ <br />