2013-04-08_HYDROLOGY - C1981041 (5)

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SNOWCAP COAL COMPANY NORTH AND SOUTH PORTALS 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 impoundment located at the South Portal. On March 19, 2013, I performed the required yearly inspection. I, J. E. Storer, 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 pond has 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 affect stability and there is no required maintenance. The impoundment was not discharging during the inspection. Pond 6, 10, 11, 13 and CBA-1 were reclaimed during 2012. Pond 7, 8 and the north decline east and west non - discharging sumps were reclaimed in 2011 Pond 9 collects run -off from the South Portal and RSRDA. The pond was dry during the inspection. Volume III, Appendix 13 -2, page RSS -15 & 15i shows that its design water and sediment capacities are 0.33 A -F and 0.33 A -F respectively. The sediment was removed from the pond during 2003 so the pond had a total depth of 9-feet. Sediment (2.6) has accumulated in the pond since it was cleaned. The percent of sediment buildup is 60% (2.6' deep divided by 4.3' maximum depth). Based on this sediment buildup and a 2003 survey of the pond after sediment was removed, the pond has the following estimated capacity. To the best of my knowledge a . •belief,° the;ifngoundment, has been maintained as designed and in accordance with the r roved_plan ariO,atilicable regulations. 11*e l a c 5 ( ze 1 3 ,_?,:,, Jt E. Storer F ' / Colorg Vrofessiorr-jineer Regis 1:ONo:) 1' Date Water Sediment Total Pond 9 - A -F 0.66 0.15 0.81 SNOWCAP COAL COMPANY NORTH AND SOUTH PORTALS 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 impoundment located at the South Portal. On March 19, 2013, I performed the required yearly inspection. I, J. E. Storer, 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 pond has 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 affect stability and there is no required maintenance. The impoundment was not discharging during the inspection. Pond 6, 10, 11, 13 and CBA-1 were reclaimed during 2012. Pond 7, 8 and the north decline east and west non - discharging sumps were reclaimed in 2011 Pond 9 collects run -off from the South Portal and RSRDA. The pond was dry during the inspection. Volume III, Appendix 13 -2, page RSS -15 & 15i shows that its design water and sediment capacities are 0.33 A -F and 0.33 A -F respectively. The sediment was removed from the pond during 2003 so the pond had a total depth of 9-feet. Sediment (2.6) has accumulated in the pond since it was cleaned. The percent of sediment buildup is 60% (2.6' deep divided by 4.3' maximum depth). Based on this sediment buildup and a 2003 survey of the pond after sediment was removed, the pond has the following estimated capacity. To the best of my knowledge a . •belief,° the;ifngoundment, has been maintained as designed and in accordance with the r roved_plan ariO,atilicable regulations. 11*e l a c 5 ( ze 1 3 ,_?,:,, Jt E. Storer F ' / Colorg Vrofessiorr-jineer Regis 1:ONo:) 1' Date