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Hydrologic Balance <br /> Pond 7 remains nearly full. The outlet gate was closed. Approved permit page 2.05-10a <br /> requires a staff gauge adjacent to the pond 7 riser that indicates the elevation of 7373.3 feet <br /> AMSL. The pond water level should be at this level with the outlet gate closed, thus ensuring <br /> the necessary capacity to hold the inflow from a 10-year, 24-hour storm event without <br /> discharging through the emergency spillway with the outlet closed. The operator should <br /> immediately draw down the water level to the required elevation by discharging the water or <br /> pumping the water to pond 6, if possible. <br /> Culvert C-14, as shown on Map 13, Sediment and Surface Water Control Plan, East Portal <br /> has now been replaced with a CMP of similar size. The inlet to the culvert was extended to <br /> the north back into the coal stockpile area to facilitate construction of a small sump hole and <br /> to avoid an overhead telephone line that complicates cleanout with boom-type excavators. <br /> The operator should ensure that the immediate disturbed area caused by the installation <br /> does not contribute sediment to the river by using temporary alternative sediment control <br /> measures and by reseeding and mulching the area as soon as possible. <br /> rM <br /> Pond 001 is the mine water discharge pond, located immediately north of the mine office. <br /> Pumping to the pond from the underground workings was observed on 4/19/2010 but the <br /> pond was not at the level where discharge was occurring. The conductivity of the water in <br /> the pond was measured at 2200 umhos/cm, which is consistent with previous readings <br /> taken. <br /> Backfilling and Grading <br /> The operator had excavated an area at the West Mine to repair an incline slope collapse in <br /> anticipation of using the slope for mine access. This excavation was approved under <br /> Technical Revision No. 51 (TR-51). Since that time, the operator has determined that use of <br /> the West Mine for ventilation and access is not practical. The operator has begun to backfill <br /> and grade the excavation, as shown below. Regrading appears about 70% complete at this <br /> time. <br /> 4 <br />