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the larger Upper Ph The reclamation grading shown on Drawing 11 reflects the proposed <br /> changes to the Upper Pit 8SOOAccess Road tO accommodate the larger Upper Pit footprint. <br /> The original haul road would be abandoned and reclaimed during the Upper Pit development. <br /> Since the Upper Pit 0900AocesS Road partial removal cannot occur until the new Upper Pit <br /> Access Road (ahnvvn on Drawing 00) is constructed, there would likely be two segments ofthe <br /> Upper Pit Access Road operating during the Upper Pit and East Pit development. Aethe Upper <br /> Pit encroaches on the southern half of the Upper Pit 6800 Access Road, the road will be <br /> abandoned and reclaimed. Based on construction timing, there may be a short window oftime <br /> where all three roads on west aide of the Upper Pit are actively used. Efforts would be made to <br /> reduce this time period and reclaim roads no longer needed as soon as possible, <br /> 3.3 Mine Reclamation <br /> Ming redonn@Uun vvOu|d be ongoing throughout the active mining phase, 88 overburden and <br /> intraburden removed during gypsum mining would be used to backfill the Upper Pit and East Pit. <br /> Backfilling the Upper Pit and East Pit concurrently with mining activities achieves the following: <br /> Reduces the level of effort required post-mining; <br /> Reduces the portion of exposed steep slopes; and <br /> Provides a storage repository for overburden and intnaburden within disturbed areas,thus <br /> reducing the overall Mine footprint and Surface disturbance. <br /> 3.4 Riparian Mitigation <br /> Dry creek beds at the Mine rarely flow (only during isolated major storms). Following cessation of <br /> mining activities, culverts (constructed to convey flows under road fills during storm events)would <br /> be removed and road fill excavated to reestablish native drainage channels. As necessary, based <br /> on the conditions encountered during culvert removal, natural channels would be constructed with <br /> n}Ck vortex weirs or isolated sections of riprap lining to prevent erosion. <br /> 3~5 Wildlife Habitat Rehabilitation <br /> After cessation of mining eotivitieo, disturbed areas would be regraded and revegetabad to provide <br /> wildlife habitat according to existing permits. <br /> 3.6 Growth Medium Handling <br /> Growth medium removed from the native ground surface during East Pit clearing and grubbing <br /> activities would be stockpiled west Of the Upper Pit (Drawings OO and 08). An estimated <br /> 244'000cubio yards of growth medium would be removed from the East Pit area, using an <br /> eeeunned depth of 0 inches over the northern two-thirds of the East Pit footprint. All material <br /> removed during clearing and grubbing (including volcanic ash, biological soil crust, etc.) will be <br /> stockpiled in the |DC8dOn identified on [)navvingS 06 and 08, although efforts will be made to <br /> salvage biological soil crust in shallower areas of the stockpile. <br /> The gS1inn8tgd 244,000 cubic yards of growth medium is not e sufficient vO|unne of material to <br /> cover the proposed disturbance (including the Upper Pit expansion, East Pit, and roads) poSt- <br /> nao|annebon grading with 8 to 12 inches of growth medium. Additional growth medium would be <br /> requ|ned, using finer-grained inert overburden or intraburden encountered during open pit mining. <br /> This finer-grained material would be mixed with native growth medium (where possible), placed <br /> in unoonnpected layers (8 to 12 inches deep) Over regraded o|opea, and track-walked to promote <br /> vegetation growth. <br /> 3u <br />