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I • lining the channel reaches above the outcrop with riprap will provide stable channels. <br />In the area along the road just below the mine site, steep slopes are present. The <br />Operator will utilize terraces on the reclaimed slope to prevent excessive erosion and to <br />provide long-term stability in cut and fill slopes. To the extent practicable, the terraces <br />shall be rounded or reduced and shaped to conform the site to adjacent terrain. No <br />material will be excavated from the berm or the slope immediately below the berm in <br />this narrowest portion of the road. Material to fill these steeper areas will be excavated <br />from the switchback just below the steep area. This material will be moved into place <br />with a dozer or other suitable equipment. To ensure that the configuration proposed <br />would create a material balance, the volume of cut and fill was calculated. The <br />tabulated calculation is presented in Table 3.9-2 and shows that there will be a total of <br />nearly 34,000 bank cubic yards of material with a slight deficit of 235 cubic yards of <br />material. The deficit is not significant. <br />Mine Road Stability Analysis <br />• To ensure that the reclamation of the mine site and road will be stable, analysis <br />of stability was performed on three areas on the road and two on the mine site. These <br />calculations indicate that the reclaimed slopes will be stable. The locations of these <br />cross sections are shown on Figures 3.1-2 through 3.1-7. These sections generally <br />duplicate the location of stability analysis performed in 1982 in response to questions <br />by the Division about future haul road construction. In conjunction with the previous <br />stability analysis, detailed geologic mapping of the area and triaxial tests were <br />performed to determine the engineering characteristics of the soil types existing along <br />the road. Some areas not analyzed previously where added because the existing <br />configuration does not include the large cuts anticipated for the previous submittal. <br />The mapping and analysis revealed that two soil types exist along the road. First is soil <br />of alluvial origin that is high in gravel and sand content and exists along the lower <br />portions of the road on the points that Geo-Hydro identified as "river terraces." The soil <br />has low cohesion, 200 PSF; a high angle of internal friction, 28°, and a density of 125 <br />• Permit Renewal 3-8 09/03 <br />