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56 (less than one square mile), application of MULTSED is not economical and again, the Green-Nnpt infiltration equation vas used as explained in Section 6.1. The two-year, 24-hour rainfall as presented in the Preliminary Data Base Report, along with the soil infiltration parameters given in Section 6.1 were used. • These parameters represent a disturbed condition and become conservative as the areas are reclaimed. The resulting peak discharge from the two-year design storm is 1.15 cfs per acre of drainage area. The existing and proposed minor diversions are all triangular in shape with 2:1 side slopes, except the minor diversion to proposed Sediment Pond "E". The minor diversion to proposed Sediment Pond "E" is designed for a trapezoidal shape with a bottom width of five feet and side slope of 2:1. The Manning'e n value ~. used is given as 0.03 in Chow (1954) for graded loam to cobbles, noncolloidal. This is descriptive of the material in which the minor diversions will be f constructed. ' The diversion to proposed Sediment Pond "E" is trapezoidal because it is designed for the 10-year, 24-hour peak discharge. This is necessary because • the diversion drains 16.55 acres of the 18.5 acres contributing runoff to pro- posed Sediment Pond "E" which is designed for the 10-year, 24-hour runoff wlume. Thus, for the 10-year, 24-hour event to be stored in the sediment pond, the diversion must be designed for the 10-year, 24-hour event. This diversion is for the recommended relocation of proposed Sediment Pond "E". The minor diversion to proposed Sediment Pond "F" is presently proposed and located on G.E.C. Map 15, Mine Plan. This present location shows the di- version flowing down the side slope of the drainage. This side slope vas es- timated to be 0.27. without adequate protection, severe gullying and erosion would occur. By relocatine the minor diversion from the sediment pond along the tce of the drainage side slope, it can be designed at a greatly reduced slope. This eliminates the requirement for added protection to reduce erosion'. The design presented for this minor diversion represents the relocation of the proposed minor diversion to Sediment Pond "F". The results of the hydraulic calculations are given in Table 15. Existing minor diversion design is based on slopes estimated from the 1" = 200' scale, five-foot ccntour mapping (1979). Location of all proposed minor diversions are . along the tce of side slopes which enables the slope to be somewhat variable. Therefore, the proposed minor diversions were designed for the permissible ve- locity recocunended by Chow (1954) for graded loam to cobbles, noncolloidal