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Coulson Excavating Company, Inc. - Bonser Gravel Pit <br />Exhibit E -Reclamation Plan <br />2} Following mining of Cell B, backfill eastern boundary slopes (3H;1V) of <br />Cell B with overburden from Cell C. <br />3) Following mining of Cell C, begin backfilling a 25 ft strip along the <br />southern boundary of Cell C with overburden from Cell D. Continue to <br />backfill Cell A with remaining overburden from Cell D. <br />4} Following mining of Cell D, continue to backfill Cell A with overburden <br />from Cell E. <br />5) Push Western Boundary pit wall to 3H:1 V (3,500 cy). <br />6) Rip shale from pit floor (--18,000 cy) and construct 2 ft thick Pond Liner <br />on slopes. <br />7) Disk, seed and fertilize areas as shown in Exhibit F -Reclamation <br />Plan. <br />8) Replace topsoil as shown in Exhibit F -Reclamation Plan (18,000 cy). <br />Pond Liner Design and Specification <br />The purpose of this section is to provide design specifications for the pond liner. <br />The objective is to design apost-mining, compacted clay liner that will prevent <br />groundwater leakage into the pond, at a rate greater than or equal to 0.03 feet3 / <br />day / feetz. <br />The source for the compacted clay liner will be the weathered zone of Pierre <br />shale occurring an average of 17 feet below ground surface. Texturally and <br />mineralogically continuous in a lateral direction, the Pierre shale is flat lying in <br />this area (Porter, 1976). The weathered zone is a friable silty clay consisting of <br />illites and small amounts of smectites (Gill et al, 1996). <br />Source Material Sampling/Laboratory Analysis <br />A 5-gallon sample of weathered Pierre shale was collected from a gravel <br />operation to the west. <br />Collected from the upper 3 to 4 feet of the weathered horizon, the shale <br />appeared very consistent with respect to color and texture with that of the <br />weathered shale within the proposed excavation area. Moreover, personal <br />communication with local excavators and drillers confirm the consistency of the <br />Pierre shale throughout eastern Loveland. This consistency is most likely due to <br />the flat lying nature of the shale in this region. <br />If the source material shows any variability with respect to color, texture, or <br />content from the sampled material, a full suite of geotechnical tests will be <br />performed. <br />Field data recorded during sample collection included: <br />Co/or-dark gray <br />