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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 occur <br />if all mine cuts are disturbed. The salvageable soil for the undisturbed areas is approximately 3-9 inches. <br />An average of 4.5" thickness is assumed for the topsoil volumes from the undisturbed 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 Trust <br />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 sediment <br />pond cleanout, pit pumping pond cleanout and slurry pond cleanout from the prep plant. This material <br />will be silty fine material and will be amended with fertilizer and mulch for reclamation. In order to place <br />4.5" of this material on the areas from pre -law disturbance less pond areas left for the final reclamation, <br />(36.5 acres- 4.4 acres pond areas for reclamation = 32.1 acres), approximately 19,420 cy is needed. <br />Assuming 10 years of topsoil salvage, 1297 cy is needed per year. The majority of this material will be <br />obtained from cleanout of the slurry ponds from the prep plant. At least every two years, cleaned material <br />will be respread over regraded areas, which will then be seeded and mulched. Therefore, approximately <br />2594 cy will be spread over 6.4 acres per year. <br />Since the plant area cannot be reclaimed until the end of the mine, the silty material for this area will be <br />stockpiled as shown on Map C-2. This area is approximately 10 acres, therefore, 4000 cy will be <br />stockpiled for final reclamation. All topsoil piles will be constructed to 2.5H1 V slopes and will be seeded <br />and mulched if they are to be in place over one year. The temporary seed mix for topsoil stockpiles is <br />given below: <br />Alma Place Mine 01/15 23 <br />