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roughened condition prevalent on the reclaimed lands as compared to undisturbed areas. An adjustment <br /> factor for the tabular C values of 0.65 was applied to reflect "moderate" surface roughness conditions on <br /> the reclamation. Several reclamation practices account for the development of this roughness. To the <br /> extent practicable, all farming operations associated with reclamation activities are performed along the <br /> contour. Specifically, seedbed preparation and seeding activities are intentionally conducted along the <br /> contour. The seeding process itself incorporates a tillage practice which results in a roughened soil <br /> surface exhibiting a series of furrows oriented perpendicular to the slope. These practices result in a <br /> roughened surface on the reclamation particularly as compared to undisturbed areas. In addition, the <br /> documented higher effective cover values established on reclamation also act to roughen the reclaimed <br /> surface by necessitating more tortuous flow paths. As a further consideration, Trapper's reclamation <br /> procedures routinely include the use of contour ditches and small depressions (i.e. livestock water tanks) <br /> to enhance slope stability and reduce erosion. Contour ditches are typically removed after vegetation has <br /> become well established, however, the livestock water tanks, which are typically situated in drainages, <br /> remain as permanent features. The contour ditches act to shorten overland flow lengths and rill erosion <br /> flow paths while vegetation is becoming established and thereby serve to protect the integrity of the initially <br /> roughened reclaimed surface until vegetation is established. <br /> In all instances, the SEDCAD 4 models demonstrate the total sediment generated from the reclaimed <br /> blocks is less than or approximately equal to the total sediment generated from the same blocks under <br /> pre-mining conditions. These results are primarily attributable to the excellent cover values documented <br /> to occur on the reclaimed lands. <br /> 1.4.3 CONCLUSIONS <br /> Both the LISLE and SEDCAD 4 evaluations demonstrate that existing conditions will result in equivalent or <br /> lesser sediment contributions to surface runoff when compared with pre-mining levels as determined by <br /> baseline data. Both methodologies possess certain strengths and limitations and each offers a distinct <br /> and different view of the test required to meet Phase II criteria. The herbaceous cover and C-factor <br /> variables are critical to both approaches. Both methods account for and reflect the outstanding cover <br /> percentages established on the Trapper reclamation in the areas being evaluated. In a similar previous <br /> analysis conducted by CDRMS (SL-1 application), these methodologies were in effect validated and found <br /> to be conservative by comparing their results to direct measurements of sediment accumulations <br /> occurring in downgradient catchments at Trapper. For this particular application, the same type of <br /> verification exercise is not feasible as extensive disturbed areas also contribute runoff and sediment to the <br /> downgradient catchments. Trapper, however, does note that the currently pending application addresses <br /> areas with strong similarities to those previously evaluated and verified by CDRMS. The vegetative cover, <br /> cover type, topographic setting, and reclamation methodologies employed are all comparable. Given <br /> these similarities, Trapper believes it is reasonable to conclude that equivalent conditions, in terms of <br /> erosion and sediment transport, prevail on the reclaimed blocks addressed by this application. <br /> 15 <br />