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minor side-cutting. There was also some under-cutting of the TRM in places, which has resulted in the channel not having vegetative cover in those locations. There is a surge pond at approximately station 13+60, where channel PM-3A intercepts channel PM-3. There was some erosion and down cutting at the inlet of the surge pond while the outfall of the surge pond exhibited little to no erosion. Although the as-built channel does not meander as much in the middle section as the designed channel, the as-built channel profile is basically identical to the designed channel profile. The following chart shows the GPS data for post-mining channel PM-3. GPS Height Northing Easting Z Corr. Correct Z Exh D Elev. Z Diff. Exh 20- 5.9 Station 7528.9 4470025.5 310002.8 40.620 7569.497 7570 0.503 7577 0+00 7582.0 4470102.6 310133.1 40.620 7622.641 7624 1.359 7628 4+96 7610.8 4470142.9 310198.8 40.620 7651.398 7654 2.602 7660 7+49 7640.9 4470184.2 310265.5 40.620 7681.546 7684 2.454 7691 10+07 7678.7 4470209.8 310325.8 40.620 7719.324 7722 2.676 7726 12+22 7698.3 4470227.1 310364.1 40.620 7738.932 7740 1.068 7744 13+60 7730.0 4470253.6 310400.8 40.620 7770.585 7772 1.415 7772 15+08 7747.5 4470291.8 310428.6 40.620 7788.169 7792 3.831 7800 16+63 7764.7 4470322.0 310460.5 40.620 7805.348 7806 0.652 7814 18+07 7802.4 4470361.6 310520.8 40.620 7843.028 7842 -1.028 7844 20+44 7846.1 4470403.6 310587.3 40.620 7886.690 7882 -4.690 7884 23+02 7894.0 4470452.7 310683.0 40.620 7934.653 7932 -2.653 7928 26+55 - Channel PM-3A runs along the north side of the Seneca II-W South area and flows basically from east to west. The channel intercepts channel PM-3 at approximately station 13+60 at a surge pond. The as-built channel length is approximately 659 feet and the designed channel length is approximately 1,450 feet in length. The channel design specifies a bottom width of 3 feet, an overall depth of 1.3 feet and a vegetation lining. The observed channel bottom width was between 3 and 5 feet, its depth was between 2 and 3 feet and its lining was vegetation, TRM and 6 inch riprap (although TRM is not specified in the approved design). The as-built channel location for PM-3A is shifted approximately 40 feet to the south, due to the change in alignment of channel PM-3 in that area. The location of the lower 659 feet of the as-built channel generally follows the designed flow path. The length of the as-built channel is approximately 790 feet shorter than the designed length. The as-built channel PM-3A basically stops at the shrub exclosure while the designed channel goes up the slope almost to the east edge of the disturbance boundary. There was significant erosion in the entire length of channel PM- 3A. There was also major under-cutting of the TRM in places, which has resulted in the channel not having vegetative cover in those locations. The as-built profile for channel PM-3A was between 3 and 9 feet higher than the design profile. Despite these elevation changes the grades of the as-built profile generally matched the grades of the designed channel. The following chart shows the GPS data for post-mining channel PM-3A. GPS Height Northing Easting Z Corr. Correct Z Exh D Z Diff. Exh 20- Station