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r <br /> <br />During the on site inspection of April 25, 1996, only two small areas, less than 300 square feet, <br />were sparsely vegetated. No signs of any significant erosion could be found. <br />SUSPENDED SOLIDS DEMONSTRATION: <br />The sedimentology analysis of the mine compared sediment production of an adjacent <br />undisturbed area to the reclaimed area using the Universal Soil Loss Equation. The two areas <br />that were compared are substantially different due to numerous liitations but this was <br />unavoidable as a reference area was never designated. <br />Both areas modeled have steep slopes and area erodibility values were book values and assumed <br />conservative conditions. Cover factors were selected from a review of actual data collected. <br />Based on the selected inputs, the calculations indicated that the reclaimed area produces less <br />than one-half the sediment of an adjacent area. <br />As mentioned above, the on site inspection showed virtually no signs of any significant erosion <br />and the three small sediment traps continue to work effectively. The combined volume of the <br />sediment traps is less than 250 cubic feet and as mentioned above, will not be removed but will <br />eventually fill and become part of the reclaimed terrain. <br />Summary and Conclusions <br />Based upon a review of the mine permit, the applicant's bond release application, and site <br />inspections, the Division finds that the Rocky Mountain Bank and Trust has completed <br />backfilling, grading, and drainage reestablishment. Additionally, the bank has established <br />vegetation which supports the approved post mine land use and meets the approved success <br />standard for vegetative cover. The Division finds that the reclaimed area subject to this bond <br />release is not contributing suspended solids to streamflow or runoff outside the permit area in <br />excess of premising levels or in excess of adjacent non-mined areas. <br />