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TABLE 4 <br />• Weighted Curve Number (CN) <br />Vegetation Hydrologic Area <br />Cover Soil Group CN (Acres) <br />Reclaimed C 81 6.3 <br />Use CN = 81 <br />TABLE 5 <br />L_ J <br />Area <br />Soil Type "k" Factor (Acres) <br />Reclaimed 0.25 6.3 <br />Use "k" = 0.25 <br />Precipitation and Storm Type <br />Precipitation depths for the 10-year, and 25-year storms were developed <br />using procedures and data published in the Soil Conservation Service <br />publication "Procedures for Determining Peak Flows in Colorado". A <br />standard SCS Type II storm was utilized for each analysis. <br />Unit Hydrograph and Surface Condition <br />The SEDIMOT II computer program provides three unit hydrograph shapes to <br />choose from in determining the runoff characteristics of a watershed. <br />The disturbed hydrograph (No. 1) was used for disturbed and reclaimed <br />areas. <br />Time of Concentration <br />The time of concentration, tc, is defined as the time required for water <br />• to flow from the hydraulically most remote point in the watershed to the <br />watershed outlet. The runoff time of concentration was calculated using <br />the following equation (USBR, 1977): <br />6 <br />