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1.4 Topsoil Handling for Gold Operation <br />The total disturbed area for the gold mining operation is 84.5 acres. Of this amount, 36.5 acres were <br />disturbed pre -1977 and no topsoil was salvaged. Approximately 48 acres of new disturbance will <br />occur if all mine cuts are disturbed. The salvageable soil for the undisturbed areas is approximately <br />3 -9 inches. An average of 4.5" thickness is assumed for the topsoil volumes from the undisturbed <br />areas. <br />The Ducommun Business Trust will do everything possible to reclaim old pre -law areas, but the fine <br />material that will be used to replace the lost topsoil can only be obtained from future operations. <br />Since the Trust cannot guarantee that future operations will be in place for the years shown in this <br />application, the Trust cannot guarantee that all previously disturbed areas will be topsoiled. The <br />Trust can guarantee that the operation will salvage all substitute fine material possible from all future <br />operations. In order to help reclaim past mining areas, substitute topsoil will be obtained from <br />sediment pond cleanout, pit pumping pond cleanout and slurry pond cleanout from the prep plant. <br />This material will be silty fine material and will be amended with fertilizer and mulch for <br />reclamation. In order to place 3" of this material on the areas from pre -law disturbance less pond <br />areas left for the final reclamation, (36.5 acres- 4.4 acres pond areas for reclamation = 32.1 acres), <br />approximately 12968 cy is needed. Assuming 10 years of topsoil salvage, 1297 cy is needed per <br />year. The majority of this material will be obtained from cleanout of the slurry ponds from the prep <br />plant. At least every two years, cleaned material will be respread over regraded areas, which will <br />then be seeded and mulched. Therefore, approximately 2594 cy will be spread over 6.4 acres per <br />year. <br />Since the plant area cannot be reclaimed until the end of the mine, the silty material for this area will <br />be stockpiled as shown on Map C -2. This area is approximately 10 acres, therefore, 4000 cy will be <br />stockpiled for final reclamation. All fines piles will be constructed to 2.5H1V slopes and will be <br />seeded and mulched if they are to be in place over two years. The temporary seed mix for any topsoil <br />or substitute fines piles is given below: <br />Alma Placer 1115 25 <br />