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side of the mesa. Generally,well graded material overlies the sill to the east while sandier <br /> overburden overlies the Pierre shale that overlies the sill in the western extents of the mesa. <br /> Topsoil, overburden, blasted shale, and separated waste fines will be stockpiled and used to <br /> backfill the slopes of mined out areas to a 3H:1 V slope during Reclamation as shown on Map F- <br /> 1. Stockpiles will be minimal and reclamation will occur concurrently with mining. If possible, <br /> overburden will be sold for non-specification construction materials. <br /> After overburden is removed and as necessary,the target sill and overlying shale,where present, <br /> will be drilled and blasted to specified rough size and sorted. Blasting will be completed by a <br /> contract licensed Operator. Overlying shale and the basalt sill will be coarsely blasted to an <br /> average size of 3' minus. Coarse blasted shale will be used as backfill in reclamation and excess <br /> coarse blasted shale will be blended with excess overburden in the dump. Blasted sill material <br /> will be loaded via front-end loader into a crusher where it will be further processed with respect <br /> to size and sorted into piles accordingly. Sorted and stockpiled sill material will be hauled off <br /> site to the market. Stockpiles of material will be located in the main processing area, see map C- <br /> 2. <br /> Blasting and mining will reach a depth of approximately 30 feet below the pre-mine ground <br /> surface along the eastern extents of the mesa where overburden is minimal. Mining depths will <br /> reach approximately 90 feet deep along the western extents of the mesa. Regardless of location, <br /> blasting and mining depths will reach the base of the basalt sill at that specific location. Prior to <br /> blasting, overburden will be pushed at a 3H:1 V slope to the adjacent area in reclamation. <br /> Therefore, the maximum active highwall will be 40 feet tall and 300 feet long after overburden is <br /> removed in a previous lift. New mining areas will be developed in approximately 20 acre phases <br /> that are detailed in Table D-1. Mining of phases will occur in numerical order; however, if test <br /> drill holes yield high shale and overburden thickness above the basalt sill, mining of deep <br /> resource phases (>80 feet to the basalt sill) may not occur until later in the mine life, if at all. <br /> Prior to initiating a new phase, the previous phases will begin reclamation. <br /> Bradford Mesa Quarry <br /> August 2019 D-5 <br />