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<br />R. G. OTTO & ASSOCIATES <br /> <br />Waste rock has been deposited in piles along the sides of Ralston <br />Creek canyon upstream of the Mine entrance. The amount of waste <br />varies oa an annual basis with the scale and nature of the mining <br />activities at the site. Of the waste material produced during the <br />period that Cotter Corporation has operated the Mine, <br />appzozimatelp 276,000 cubic yards is presently in waste storage <br />are:s oa the site. <br />In the pears prior to 1976, all ore-bearing and associated waste <br />rock was transported to the surface and separated by hand-probiaq <br />with a geiger counter. The millabl• ore was removed f:•om the site <br />~, and the remaining waste rock was piled along th• west k~ank of <br />`c-~~'~ Ralston Creek, upstream of th• Mine (Figure 3). A- mect~ani2ed <br />ore-sorter was constructed is 1976 to replace the laborious and <br />inefficient hand-probiaq process. Development rock (rock visably <br />not ore-bearing and therefore not passed through the ore-sorter) <br />continued to be stored on the so-called west pile. Ose-sorter <br />reject, a miz of unscreeaed development rock and ore-bcearinq rock <br />of grade too low to mill economically, was first washed then <br />placed is a second waste rock pile on the east bank of the stream, <br />again upstream of the Mine site. The east waste pi1• was used :s <br />construction material for the emergency water storage pond in <br />1983. The disrupted area has been reclaimed by grading the pile <br />basement material to conform with the natural slope of the canyon <br />and seeding. <br />f~; <br />k <br />