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The sediment pond will capture all surface flow of storm water within the affected land <br />boundazies(permit boundary in this case). The watershed area within the mine permit and <br />affected land boundaries is considerably less than the watershed map shown on Exhibit <br />G, however, the sediment pond as designed should easily handle the estimated 20 cfs <br />maxunum flow velocity of a ten year, 24 hour storm event. Obviously, the total volume <br />output estimation for even a 10 yeaz event will likely exceed the storage capacity ofthe <br />pond and will flow through the rip-rapped spillway structure while retaining sediments in <br />the pond. <br />4. This pazcel of land was evaluated via inspection of present operating faces and field <br />investigation of un-mined bedrock exposures. The subsurface material appears to be a <br />highly fractured and folded granite gneiss bedrock, with substantial weathering of the <br />granite gneiss to "grus", a course grained fragmented rock with some clay aheration. The <br />present face displays the weathered rock in vazious zones noted by color (shades of <br />green, red), and relative hardness. The southwestern comer of the site and elongate ridge <br />Winning NW-SE along the north central part of the site will be the main locations of <br />"grus" material desved by the county for road materials. The central portion of the site <br />will likely contain a thick soil layer overlying granite bedrock and will not likely be <br />mined, if at all, until late in the Gfe of the mine. However, the central portion of the site, <br />which may contain as much as 8' of soil and subsoil overlying bedrock, will be used to <br />access the north-central portion of the site so that mining will progress from the <br />north/north central portion of the site in a southeastern direction. This direction of <br />mining will keep the disturbance flanked from view from traffic along CR 2. The central <br />portion of the site may also afford fines materials to blend with granite gneiss in the event <br />that a fines component is needed sometime in the future. The outcrop viewed along <br />County Road 2 displays substantial folding and fragmenting of the granite gneiss bands, <br />which will probably allow for dozer ripping of the bedrock for feed to crushing circuits. <br />It is assumed that dozer ripping will produce the weathered bedrock to 40'-50' from <br />present surface. Obviously, rock conditions may change at depth, limiting the final <br />elevation of the pit floor. The Reclamation Map was constructed to show maximum <br />possible excavation estimated. In the event that rock conditions result in a significant <br />change (less) in final excavation elevation, a TR will be submitted at that time. <br />Overburden is not present in significant quantity, as weathered rock and fines aze <br />typically included in the crushed final product. All topsoil materials will be stockpiled <br />for future use or preferably live hauled to reclaim azeas. <br />2 <br />