Laserfiche WebLink
January 2002 Seneca 77-W South E.xpan.non * Drainage and Sediment Control Plan • Page 5 <br />• <br />TABLE 3 <br />CONTROL FACTOR <br />Cover Cover T e Ve etation Control Factor <br />Undisturbed Aspen/Mountain <br />Shrub 25% canopy (2 m fall height), <br />80% round cover 0.042 <br /> Sagebrush 25% canopy (2 m fall height), <br />80% round cover 0.042 <br /> Herbaceous No cano , 80% round cover 0.043 <br /> Mesic Draina a No cano , 40% round cover 0.100 <br />Disturbed Bare Ground None 1.0 <br />3.5 PRACTICE FACTOR, P <br />The practice factor is used to account for conservation practices for the watershed. The values utilized <br />are shown in Table 4 (Renard et al, 1996)(Schwab and Warner, 1987): <br />TABLE 4 <br />PRACTICE FACTOR <br />Surface Surface T e Practice Practice Factor <br />Undisturbed Varies None 1.0 <br />Disturbed Topsoil Stripped <br />Spoil Rough and Irregular <br />Rough and Irregular 0.9 <br />0.7 <br />3.6 SEDIMENT PARTICLE DISTRIBUTION <br />A sediment particle size distribution was input into the SEDCAD computer model. The distribution <br />was obtained from previous analyses presented in the Seneca II mine permit and is shown in the <br />SEDCAD printouts. <br />• <br />1121i%H * 165 S. Uuioa Boulevard, Suite -110 * Lakemoot! Colorado 80228 * (303) 763-5140 <br />TR-59 Revised 05/07 <br />