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EXHIBIT C - paragraph 9 <br />Guidelines for the design, construction, operation, and <br />maintenance of mill tailings ponds have been established by the <br />U.S. bureau of Mines, the Colorado Division of Mines, and the <br />Colorado Water Quality Control Commission. Using these <br />guidelines, a tailings pond that will be built by employing the <br />upstream method of construction. These guidelines will also be <br />followed during the actual construction, operation and <br />maintenance of the tailings retention Structure. This specific <br />tailings dam design was chosen because it proves structural <br />stability, affords adequate storage capacity. utilizes readily <br />available borrow material, and allows for the construction of an <br />embankment that will be built in several stages. Environmental <br />considerations were also taken into account when this particular <br />design was selected for tailings disposition. The design <br />principals for an upstream tailings dam are compatible with the <br />location selected for tailings impoundment, and with the type of <br />milling operation that will be conducted. <br />The upstream method of tailings dam construction begins with the <br />construction of a low starter dike, ar toe dam. this is built to <br />contain the tailings during the initial stages of deposition. <br />Tailings are discharged off the upstream face of the toe dam at <br />regular intervals from spigots connected to peripheral discharge <br />line. A favorable gravity separation of the tailings results <br />from this type of discharge. The coarsest sand particles drop <br />out closest to the point of discharge, and the finest particles <br />(the slimes) flow into the center of the tailings dam, where the <br />excess water forms a localized pond. Because of the relatively <br />large size differential between the coarse and fine fractions of <br />the tailings, the coarse sand particles Form a beach in front of <br />the spigots. The sand beach that is formed around the upstream <br />perimeter of the starter dike is used for raising the height of <br />the impoundment dam. This is accomplished in stages. When the <br />initial pond is nearly filled, the starter dike is raised with <br />addition borrow material and sands, and the cycle is repeated. <br />Since the subsequent layers of tailings are retained by the <br />successive dikes, it is important for these dikes to be built on <br />a stable base. <br />