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SPECIAL CONSIDERATIONS FOR UPPER GRASSY VALLEY STORM WATER MANAGEMENT <br />The drawings show the essence and details of the plan for Upper Grassy Valley <br />Storm Water Management. There are certain specific conditions that have been <br />considered and addressed in the design. Those are generally described below. <br />Storm water Interception and Bypass around the WHEX Pit — <br />The proposed mine plan includes the construction of the Wild Horse (Northeast) <br />Extension of the East Cresson Mine in 2013. The removal of ore from that area will be <br />followed, in close order, by backfilling the WHEX pit to the original contours. After the <br />backfill of WHEX has been completed that area (shown on Details 1 and 7) will be <br />reclaimed by: (1) installation of growth media, (2) reseeding, and (3) reestablishment of <br />drainage channels. <br />County Road 82 was recently (2010 and 2011) relocated along the north <br />boundary of the mine. The storm water drainage from the north side of that road <br />currently discharges through a drainage culvert into Upper Grassy Valley, but will <br />discharge into the WHEX pit when it is constructed unless other provisions are made to <br />bypass the runoff around the pit. Accordingly, EMP -18 will be constructed on the north <br />(up- gradient) side of the WHEX pit to intercept the runoff and road drainage. The <br />accumulated storm water contents must be pumped around WHEX and will be <br />discharged into EMP -16 on the west side of Upper Grassy Valley. The storm water will <br />then flow to terminal EMP -17. There is no electrical power grid in that immediate area. <br />During most circumstances, storm water accumulations will be pumped through a 6 -inch <br />pipeline to EMP -18 using solar powered pumps. If, or when, a more intense storm <br />occurs the water will be removed using a mobile diesel - powered pump. <br />Since both EMP -18 and EMP -19 will be in close proximity to the high -walls of the <br />WHEX pit, and since both are located in more permeable Quander - Bushpark soils, it will <br />be important to construct the basins and embankment as "tight" as possible to avoid <br />leakage into the pit. The drawings specify the selection of soils with high proportions of <br />clay, and rigorous compaction to ensure that the basins and impoundments are as <br />water -tight as possible. Seltz soils from the clay- borrow area may be desirable for that <br />construction. <br />Client: CC &V Gold Mining Co. 2/2/12 <br />Title: Storm Water Management, MLE2 Page 9 <br />