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SACRFILL AND GRADING <br />The east berm has been removed as called for in the approved Reclamation plan <br />(page 183 of permit application). The former berm area is a strip of ground <br />approximately 11 ft. wide by 180 ft. long; total area is approximately 0.05 acre. <br />This strip of ground has been graded to the same level as the adjacent former <br />facilities yard area. The former berm area was seeded during the inspection. As <br />explained in the preceding discussion of Roads, the material from the berm is <br />rocky and has been spread on the access road. <br />The operator recently demonstrated in Technical Revision 12 that the pond is no <br />longer needed for sediment control, and consistent with that revision, the <br />emergency spillway has been removed. This spillway was a trapezoidal notch in <br />the pond embankment that was lined with concrete blocks. The notch has been <br />filled with material from the removal of the east berm. Since the spillway was <br />removed, however, the landowner has expressed a desire to leave the pond as a <br />permanent structure because the pond embankment provides the former facilities <br />yard area flood protection from Trout Creek. <br />Retention of the pond as a permanent structure will require reconstructing an <br />emergency spillway to the design specifications contained in a permanent <br />impoundment demonstration. The operator's representative submitted a <br />demonstration (Technical Revision 13) to the Division on the same day as this <br />inspection. Although the pond currently lacks an emergency spillway, the pond's <br />storage capacity of roughly 30,000 cubic feet is significantly greater than the <br />approximately 6,700 cubic feet of runoff that can be expected from a 100-year, <br />24-hour storm. The pond's overcapacity results from it having been originally <br />designed for a much larger area than its current 3.7 acre drainage area. The <br />primary spillway remains in place. 1t is a 4-inch pipe in the embankment. <br />We walked over the reclaimed areas. Values reported for vegetative cover and <br />species diversity in the bond release application were compared with field <br />observations. All areas appeared consistent with the data in the bond release <br />application. Smooth brome and orchard grass dominated herbaceous cover in all <br />areas. No weed problems or significant bare areas were found. The Division is <br />conducting an in-office evaluation of vegetation data in the bond release <br />application. <br />SLIDES AND DAMAGE <br />Slope stability. No new rock falls were apparent on the former portal bench. The <br />ground appeared stable in the area of the three sealed drift portals and the <br />sealed fan portal. No evidence of instability on reclaimed slopes was found. No <br />tension cracks were found at the tops of slopes and no bulges were evident at the <br />base of slopes. The slope in the former office area appeared stable. <br />Erosional stability. Vegetative cover on reclaimed areas appears to be preventing <br />rill and gully formation. Hillslopes did not show significant down-cutting from <br />concentrated flow, even on the steep former office area slope. the gabion-basket <br />lined ditch on that slope was in good shape. No delta or sediment fans were <br />found. <br />4 <br />