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Dewatering Evaluation Report <br /> Asphalt Specialties Company,Inc. <br /> Weld County,Colorado <br /> Page 5 <br /> Table 2-Phase II Post Slurry Wall Water Levels <br /> MW-1 250 4665.06 4666.22 4666.22* 0.00 1.16 <br /> MW-2 162 4659.00 4658.67 4658.71* -0.04 -0.29 <br /> MW-3 50 4663.04 4664.24 4664.24* 0.00 1.20 <br /> MW-4 488 4660.47 4659.53 4659.56* -0.03 -0.91 <br /> Note-*Denotes water level without dewatering <br /> As mentioned it is our understanding there is a surface water augmentation project just to <br /> the west of the proposed mine and this project consists of injecting water to the subsurface. If <br /> necessary ASCI will install a drain to mitigate any groundwater mounding west of the study <br /> area. A drain boundary condition was modeled adjacent and parallel to the western most <br /> Phase I slurry wall. The drain simulation was one foot below the average water table elevation <br /> for ASCI well MW-1 and a conductance of 1000 feet per day was assigned to the drain <br /> (ModFlow then automatically calculates the conductance in ft2/day). A south to north <br /> slope of 0.0013 feet per foot was assigned to the drain. Table three shows the predicted <br /> influence of the drain will mitigate any mounding to the west of the mine.Graphs depicting the <br /> predicted water table values are presented on Plates 15 and 15A. Plate 16 depicts predicted <br /> water table contours for the drain simulation with no dewatering influences and Plate 17 <br /> depicts the drain simulation boundary conditions. <br /> Table 3-Phase I Post Slurry Wall Water Levels With Drain&Gallery <br /> MW-1 250 4665.06 4664.39 4666.22 -1.83 4664.40 <br /> MW-2 162 4659.00 4658.88 4658.71 0.17 4658.94 <br /> MW-3 50 4663.04 4663.16 4664.24 -1.08 4663.29 <br /> MW-4 488 4660.47 4659.87 4660.11 -0.24 4660.15 <br /> Note-Column 6 is the difference between column 4 minus column 5 <br />