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Slope, S (%): Can be entered by the user or the program calculates the slope when the user <br />selects an area from the screen. <br />Length (L): Can be entered by the user. If the user selects an area from the screen, the length is <br />not calculated since the Gross Erosion is directly calculated. <br />Topographical Factor (Ls): Will be calculated from Length (L) and the Slope (S), only when <br />these values are entered by the user directly, as against calculated by the program from the <br />screen. In the second case, the value of Ls is calculated for individual grids and not for the entire <br />area. <br />Ls = (L/72.6)^m * ((430*S^2 + 30*S + 0.43)/(6.613)) <br />where L and S are defined above and <br />m = 0.5 if S=>5%; = 0.3 if S<= 3%; = 0.4 otherwise. <br />Gross Erosion, E (tons/acre/year): Calculated from the above defined parameters for each area <br />defined. If the user selects an area from screen, E is calculated in each grid and the cumulative <br />value is calculated. <br />E = R * K * Ls * C * P, where all the parameters are as defined above <br />Volume Calculations: <br />Required User Input <br />Sediment Delivery Ratio (DR): Default = 0.37 <br />Time Period, T (years): Time of analysis; typically the time of the storm event <br />Density of the sediment (D): The post -deposit density of the sediment <br />Runoff (I): Calculated from some other routine like Curve Number and Runoff <br />Total Erosion (E, tons/year) = Sum of (E * Area) for all the areas. <br />Total Yield (Y, tons/year) = E * DR <br />Sediment volume per year (Vs) = Y / Density <br />Total Sediment Volume = Vs * Time period <br />Runoff Volume = Runoff (I) * Total Area <br />Total Pond Volume = Runoff Volume + Total Sediment Volume <br />Pond 008 was constructed in the fall of 2000. Pond 009 was excavated in the spring of 2002. <br />Pond 012 was excavated in spring 2005. Ponds 011 and 013 were constructed in late 2007, while <br />Section 2.05.3(3) Page 16 April 2017 (MR -104) <br />