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• Pond 016A Removal <br />- A portion of the existing embankment will be lowered/removed to drain the <br />current pond and then be reconfigured to fit the relocated Channel PM -2 design <br />- An under drain will be installed through the bottom of the pond <br />- 3 foot trench bottom width <br />- 6" perforated PVC placed along bottom of trench <br />- 4" minus gravel —3 foot depth <br />- Material will be excavated from the nearby slide area and placed in the Pond <br />016A impoundment area. <br />- Pond 016A will no longer serve as a sediment structure. <br />Relocated Channel PM -2 (extension through Pond 016A) <br />Approved: <br />Appendix 20 -1, Post Mine Drainage Channel Design, Channel PM -2 Design: <br />- 10 foot channel bottom width <br />- 6 inch riprap or TRM <br />- 1.1 foot total depth (water plus freeboard) <br />Proposed: <br />- 10 channel bottom width <br />- +6 inch riprap or TRM <br />- 1.1 foot total depth (water plus freeboard) <br />Topsoil <br />- Topsoil will be salvaged from the proposed additional disturbance areas, except <br />in areas that are to steep to safely operate equipment, <br />- The disturbed area will have topsoil replaced; however,- no topsoil will be <br />replaced on the "steep cut slope" left in competent material. <br />- Red rock material will be spread on the lower portion of the cut slope to reduce <br />erosion and to enhance revegetation by providing microsites for plants. The <br />approved Upland and Concentrated Shrub seed mixes will be used to seed the <br />area of red rock. <br />- The entire area will be seeded with an appropriate approved seed mix. <br />• Pond 016 Capacity <br />- Pond has been recalculated to ensure it meets minimum sediment and water <br />storage requirements following slide area reconstruction. <br />- SEDCAD4 results are attached. <br />• Shrub Plot Slump Remediation <br />- Postmine Channel PM -2 relocated to capture subsurface flows within slump <br />area, in addition to the surface flows from PM 2A, 2B and 3 <br />- Area regraded and reseeded <br />AM -71 4 8112 <br />