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<br />' discharge reach is relatively short in the upper more severe slopes of these basins which <br />inhibits scouring damage. <br />' B: Proposed Drainage: Figun; 2.3b depicts the proposed final grading of the pit together with <br />' the associated drainage basins. Basins I, II, and VII are identical to their present <br />configurations, discharge from which is not affected by the mining. Basin VIII is also <br />identical to its existing size, yet is different with respect to its decreased upstream drainage <br />' area. Basins III thru VI have changed in size due to the mining plan, yet Basins III and N <br />still exhibit their natural ground covers. <br />' Basin V (6.68 acres) is primarily mined surface with slopes varying from 333'0 on the upper <br />west end m 10'~o at the pit floor. Runoff will occur as sheet flow discharging within a natural <br />draw to the northeast Emphasis is placed on the flatter slopes (less than 10'%) immediately <br />above the entrance to the draw, minimising sedimentation and scouring within the natural area <br />' of the drew. A small silt basin may be conmucted at the lower entrance to the draw within <br />the pit boundary to catch any flowable sedimentation <br />' Basin VI (6.08 acres) allows for compatible transition from mined slopes of 10'Yo to the natural <br />ridge on the south side of the proposed pit. Runoff occurs as sheet flow in the upper 33go <br />slopes, discharging northeasterly to the pit floor where the flatter lOg'o slopes can rum the <br />' runoff to a southeast direction and exit the proposed pit area through the existing roadway. At <br />this point nmoff is channeled Through Basin VIII ro the existing sedimentation pond as is <br />presently noted. The applicant will maintain hay bales within the discharge area of Basin VI <br />' commencing with the initial mining phase through the permit duration. Upon completion of <br />the Phase I mining operation, a small silt basin may be required at the discharge point until <br />reclamation is established. <br />' Emphasis is called to the major shift in runoff direction by the proposed mining plan. In the <br />present or existing condition the sedimentation pond receives nutoff from Basin I throu <br />' Basins VI and VIII for a total area of 19.52 acres. The proposed mining plan shifts discharge <br />from Basin I through Basin V where the gentler pit floor slope and natural downstream ground <br />cover can diffuse runoff and increase infiltration Natural ridges have been preserved along <br />' the pit perimeter in Basins III, VI and VII to minimize sedimentation flows off site. Knobs or <br />knolls are preserved in Basins N and V resulting th a flatter pit floor bottom inhibiting <br />erosion damage as runoff exits the site. <br />' 6. EROSION CONTROL MEASURES <br />' A: Proposed Pit: Figures 2.2 a, 2.2 b and 2.2 c show the respective phased mining plans for <br />the proposed pit area. Potential erosion areas are identified and minimized with the addition <br />of hay bales m detain and diffuse nmoff channelization pattern Additional silt basins may be <br />' installed az the discharge areas of Basins V and VI. As Phase I is completed, reclamation <br />will commence along the south and southwest edges of the pit and the incidental draw which <br />is created in Phase I. Runoff originating above these reclaimed slopes is insignificantly small <br />' resulting in little damage. As each phase is completed, the reclamation will begin <br />simultaneously with grading commencement in the next phase. In this manner, proposed <br />' P-12 <br /> <br />