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• <br />As mentioned in Exhibit D -Mining Plan, topsoil and overburden material are salvaged prior to <br />mining gravel. Topsoil will be salvaged to a depth of 12 inches, when present, with scrapers or <br />front end loaders. The remaining material is assumed to overburden. Initially, when a pit is <br />developed both the topsoil and overburden material will be stockpiled in sepazate piles and <br />marked. The piles will be seeded with oats, Western wheatgrass, and Intermediate wheatgrass to <br />stabilize the pile and protect it from erosion. <br />After sufficient pit area has been opened, overburden material will be placed against the pit <br />highwalls with either scrapers or trucks. Once the 3H: I V or 2H:1 V slopes are in place, topsoil <br />will be placed to a depth of 6"-l2"on the portion of the 3H: l V slope that will be above the <br />assumed lake elevation using scrapers. The reclaimed areas will be seeded in the fall with the <br />approved revegetation seed mix. <br />In disturbed areas around the edge of the pit that are not a slope to a lake, the area will be filled to <br />grade with overburden material as needed and then ripped to a depth of 18" prior to placing <br />topsoil. Topsoil will be placed in these areas to a depth of 6" to 12". <br />In disturbed areas where wetlands will be created, a depression will be created with a bottom that <br />is from 12" to 24" below the expected water elevation in the wetland area. The grade for the <br />bottom of the depression is set be 12" to 24" below the wetland water elevations that existed <br />prior to being disturbed by mining. In these wetland areas topsoil will not be place in areas that <br />will be covered by water. In areas not covered by water, topsoil will be placed to a depth of ti" to <br />12" prior to seeding. <br />The Renewable Resource Area will be reclaimed as a backwater area if the main river channel <br />does not inundate the area first. The assumed water elevation of the backwater area is 5332. The <br />bottom of the area will be excavated to an elevation of 5330 and 3H:1 V slopes will be created <br />around the perimeter of the azea. If the vertical distance from the slope crest to the water surface <br />elevation, 5332, exceeds 3 feet, then the reclaimed slope will be seeded with the approved <br />reclamation seed mix. The 3H: I V slopes will be constructed out of native materials in the <br />Renewable Resource pit area. Topsoil that has been salvaged fron the Renewable Resource Area, <br />will be spread over the area to be seeded. <br />If the main river channel realigns itself and inundates the Renewable Resource Area, no <br />reclamation is required. <br />A material balance analysis comparing material available and material required for reclamation has <br />been done. The results of this analysis are presented in Table E-3. Tables E-3-A, B, C, D <br />provide the printouts from the volume calculations for topsoil and overburden available and <br />topsoil and overburden required for reclamation for each mining area. The volumes were <br />calculated using Land Design Desktop as described in Exhibit D -Mining Plan. The Renewable <br />Resource Area has been included to quantify the amount of material to be moved to calculate the <br />reclamation liability. <br />