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