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foot diameter by 49-foot-high and will be constructed so the slopes match the natural angle of repose for <br /> stability.At the maximum size,the backfill stockpile will hold approximately 10,000 tons of material.The <br /> backfill stockpile will contain residual moisture of at least 10%.The location of the backfill stockpile is shown on <br /> Figure D3,Site Plan. It is anticipated that a larger out-of-pit backfill stockpile will be required in the initial <br /> operation years until the mining pit has been sufficiently developed to allow direct backfill operations to begin <br /> as part of regrading and reclamation.The location of this larger backfill stockpile is shown on Exhibit C6.1 and <br /> C6.2, Mining Plan Map.This larger backfill stockpile will be covered with topsoil and seeded to prevent erosion <br /> and reduce fugitive dust emissions at the site until it can be used for backfilling operations.The proposed seed <br /> mix is shown in Exhibit E. It is estimated that by approximately year 2, regrading operations will begin. For the <br /> majority of the life of the mine,operations will be conducted with concurrent backfilling and reclamation. <br /> The majority of the processing will be in an enclosed facility.An initial wet screening will remove large material <br /> that will be transported to the backfill stockpile or backfilled directly into the pit.This material will be damp, <br /> with no free draining water. Raw plant feed will continue through size separation steps. Inert surfactants will be <br /> used in the process to assist in separating clay materials and feldspar from the industrial proppant sands. Clay <br /> and feldspar removed from the material will be dewatered using filtration equipment, and the damp material <br /> will be handled with the oversize material. Product will be dried and stored in silos for loading. It is anticipated <br /> that only approximately 40-50%of the raw sand material removed during mining operations will be sold as <br /> product. 50-60%of the total volume(overburden, large rocks and boulders, and over/undersized material)will <br /> be returned to the site and used as backfill in the regrading and reclamation activities. <br /> 6.4.4(b) Earthmoving-Material will be excavated from the pit using excavators,dozers and front-end loaders. <br /> No blasting is expected to be required. Dozers will be used to push material towards the loading equipment <br /> (i.e.,front-end loaders, or excavators) in order to increase loading productivity,as well as to push down and <br /> 'level' or regrade any unstable or unsafe slopes. Due to their versatility and the ease with which they can tram <br /> and relocate to different working areas,the front-end loaders will perform the majority of topsoil and <br /> overburden stripping, as well as mining of the sands.The excavators will be used to support the front-end <br /> loaders and will primarily be used in areas where the sand is better handled in a 'underhand' digging <br /> configuration, e.g.,when recovering a 'wedge' of material that is closest to the highwall, or when the excavator <br /> is in position above the truck. Once loaded,trucks will be used to transport all raw plant feed to a raw plant <br /> feed stockpile at the processing plant. In later years, a closed loop slurry pipeline may be used. If a slurry <br /> pipeline is used,a technical amendment of the mine permit will be completed prior to beginning construction <br /> on the pipeline. It is estimated that on average approximately 4 mining trucks will be required in years 1-10, <br /> increasing to approximately 7 mining trucks after year 10. Please see Table D1 for haul length data and the <br /> estimated number of truck trips per day. A small portion, approximately 0.3 miles, of haul road at the sand <br /> wash plant will be paved to assist with dust emissions.Additional portions of the haul road may be paved or <br /> graveled as necessary throughout the life of mine. <br /> Pre-stripping of the topsoil from the initial mining phase will begin during construction of the facilities. <br /> Figure D6 shows a typical cross section of the pit slopes and anticipated pit depth in relation to the water <br /> table. Pit slopes will be established to ensure safe,stable working areas. Overall pit slopes,where <br /> constructed by dozer push operations,will not exceed 3:1.Where the ultimate pit slopes is established by a <br /> series of vertical working benches,the individual bench slopes will be the approximate height of the hinge- <br /> pin of the primary loading machine; currently anticipated to be an approximately 7 cubic-yard class(bucket <br /> capacity)front-end loader,with a hinge-pin height of approximately 10'. Minimum bench widths will be <br /> established so that the ultimate overall slope of a benched wall will be no steeper than 3:1,while allowing <br /> safe working and trafficable zones.Table D1: Equipment Details <br /> 2 <br />