2010-04-21_HYDROLOGY - C1981025 (2)

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MINREC, INC. NORTH THOMPSON CREEK MINES IMPOUNDMENT YEARLY INSPECTION In accordance with Rule 4.05.9(14), all impoundments shall be inspected at least yearly to determine if the impoundment has been maintained as designed, and in accordance with the approved plan and the applicable regulations. This yearly inspection is for the impoundments located at the North Thompson Creek Mines. On April 13, 2010 1 performed the required yearly inspections. I, J. E. Stover, have a wide variety of experience in the design and construction of earth fill embankments. Nothing was observed during the inspection that would indicate the ponds have a potential for failure. There was no appearance of erosion, instability, structural weakness or other hazardous conditions. There are no required monitoring procedures or instrumentation other than quarterly and yearly inspections. There are no. aspects which might aff ect stability and there is no required maintenance. The long pond and treatment ponds T-1 and T-2 were full as expected with approximate water level elevations of 7522, 7515 and 7511 respectively. T-2 was discharging into outfall 001 at approximately 15 gpm. Sediment pond 9 contained about 1.0 feet of water at approximate elevation of 7497. Water depth in the long pond is approximately 24". Water depth in the treatment ponds T-1 and T-2 is approximately 4 to 5- feet. The impoundments have the following capacities: IMPOUNDMENT CAPACITIES - ACRE FEET Water Sediment Total Long Pond 0.35 N/A 0.35 T-1 0.29 N/A 0.29 T-2 0.24 N/A 0.24 Pond 9 0.53 0.42 0.95 Notes: 1. Capacities are based latest digital topography. To the best of my knowledge ar Ir??undments have been maintained as designed and in accordance with the approve® c ancf ap? egulations. ® a m 0?o°? o? ??rQ 1°2 0'' o ,pa s0 E. Stover oo ??,0, Date Colora ® 1?f?ssi, sneer Regist tl?l a?•?30