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.. ... , ..,-.:.. 5..~ The former metal mine working referred aze located west and above active~mazble ~ :.° -.~ . .- . <br />mining area. The former workings are located on the Pre-mining Plan Map . _ <br />Exhibit Cb Existing Mine Disturbance. <br />6. Area of land to be affected will total 66 acres, with the primary unaffected lands <br />located in the southern mazgins of the pemutted land boundaries. <br />7. The topsoil stockpile location proposed along ibe western edge of tbe pemritled <br />area is intended to be located on a flat bench of footwall quartzite bedrock <br />approximately 80 feet wide- The bench base will be graded i ° to the west and l ° <br />south to allow for surface water flow to be deected south and along a ditch <br />constructed in topsoil material along the eastern side of the topsoil pile. The <br />topsoil will be placed on the bench at slopes no greater than 2.5:1 and erosion <br />control measures will be performed, including oantour furrowing and planting of <br />native seed mix as described in the reclamation exhibit to minimize soil loss. All <br />seeded areas will be mulched to promote grass and forb development at a rate of <br />2000#/acre. A ditch will be constructed along the eastern base of the topsoil pile ` <br />to collect sediment and direct surface runoff south to bench collection ditches that <br />will ultimately direct run-off to the lower pit. The ditch dimensions will be a <br />minimum of 5' wide and 12-18" deep and will be coattrrrcted with a dozer or <br />grader cut in anon-isosceles "v" configuration The topsoil stockpiles will be <br />built no taller than 35' fiom base to highest point and may be built <br />higher than the wes sides a excavation cut, depending upon thickness of soil horizon <br />incurred. The west side of the stockpile wilt have a similar ditch cut constructed <br />along the base graded to drain to the south. Of the 80' of base width, <br />approximately 65' or less will be utilized for topsoil stockpile footprint, with the <br />eastern IS needed for ditch construction and a low berm (1'-2' high) along the <br />outer edge to enhance rainfaWsnowmelt drainage towards the ditch. As depicted <br />on the Mining Plan Map Cc, the topsoil stockpile may be extended for several <br />hundred feet along the uppemtost portion of the western side of the affected land. <br />This elongate, relatively small cross-section volume stockpile configuration is <br />intended to minimise anaerobic soil condition formation during tbe stockpile <br />phase and allow for efficient application of the topsoil on the mine bench tops <br />directly behove ibe point of stockpile location at the appropriate time. <br />8. Other topsoil locations depicted on the M'uung Plan Map Cc show potential <br />locations along the eastern portion of the affected lands, adjacent to the sediment <br />control berm sepazating the Taylor Gulch drainage from mine site drainage, <br />although no reference to footwall bencbes is made other than the one described <br />above located along the extreme western edge of the affected land. All topsoil <br />stockpiles referred to will have erosion control addressed via surface manipulation <br />techniques such as contour furrowing, re-vegetation via native grass and forb <br />seeding, mulching, and adequate ditchres installed along stochrprle perrmetets to <br />eliminate soil loss due to storm impacts. Ditches will be maintained throughout <br />the mining season and will be inspected and worked as needed prior to all <br />seasonal shut-down of site. The topsoil stockpile shown on the map along tbe <br />southern end of the lower staging area may 6e integrated into thre erasion control <br />berm defining drainage along the eastern edge of the mine site, depending on the <br />