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<br /> <br />1.3 Criteria <br />To qualify as a Small Area Exemption (SAE), runoff from disturbed ground must not exceed effluent <br />limitations during a 10-year 24-hour storm event of 0.5 milliliters/liter (mill) of peak settleable concentration <br />(SSp) of sediment (reference Rule 4.05.2, Division of Minerals and Geology). <br />2. SEDCAD+ INPUT PARAMETERS COMMON TO ALL <br />ANALYSES <br />3. SEDCAD+ INPUT PARAMETERS COMMON TO ONE OR <br />MORE AREAS <br />A number of input parameters into the SEDCAD+ model are common to all areas in this analysis and review. <br />The Storm Type was selected as SCS Type II. The rainfall depth was selected as 1.90 inches. The storm <br />duration is the 10-year, 24-hour event. The SEDCAD+ model (hydrograph convolution interval) time <br />increment was selected as 0.1 hour. <br />Input parameters into the SEDCAD+ model common to one or more of the areas in this analysis and review. <br />They include the particle size analysis of the soil, and the soil erodibility factor. <br />3.1 soils <br />.:,? <br />A representative (based on the soil description) particle size distribution used in the analysis is as follows: <br />Percent of Eroded Particle Size Fraction Passin <br />Screen Sizes in mm <br />2.00 100 <br />1.00 I 90 <br />0.500 31 <br />0.250 72 63 <br />0.125 <br />0.063 54 <br />0.016 I 41 <br />0.004 30 <br />3.2 Land Use Condition (LUC) <br />• <br />LUC values are consistently applied as follows (reference SEDCAD+ guide): <br />For undisturbed portions of the watershed, overland flow: 2 (woodland). <br />For the cut slope, overland flow: 5 (nearly bare and untilled). <br />2