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Practice Factor "P" <br />This factor is only applicable when such practices such as contouring perpendicular to <br />the slope or other similar practices are used. None of these items are applicable to the <br />post-mining case and although dozer tracks and other equipment roughness marks were <br />left perpendicular to the slopes throughout the reclamation process, 10 years have <br />elapsed since the areas was reclaimed and these items have primarily disappeared. <br />Therefore, the "P" factor for the post-mine cases is 1.0. <br />Calculations <br />Area R K LS C P Sediment Acres Total Erosion in <br /> Loss in Tons/Yr <br /> Tons per <br /> acre/year <br />Segment 1 26 0.37 4.4 0.013 1.0 0.550 0.460 0.253 <br />Segment 2 26 0.37 0.78 0.013 1.0 0.098 0.790 0.077 <br />Segment 3 26 0.37 0.34 0.013 1.0 0.043 0.100 <br /> 2.360 <br /> Total 0.431 <br />Conclusions <br />The case results show that the erosion for the post-mining case in the disturbed areas is very <br />low. This result is confirmed by unmeasurable sediment delivery to the pond over the entire <br />10 year period after reclamation. Also, no sediment deposition is occurring at any areas <br />upstream, such as where the three segments meet. <br />3) Contribution of Additional Suspended Solids to Receiving Waters and Comuliance <br />with Federal Water Quality Standards. <br />Due to the fact that the pond has been in place for 10 years after initial reclamation with no <br />measurable inflow of sediment demonstrates that no runoff from the site could contribute <br />suspended solids above natural conditions. Also, the vegetation at this time is better than the <br />average over the 10 year period, therefore, subsequent years should be even better at <br />8 <br />