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<br /> <br />Exhibit E -Reclamation Plan (continued) <br />C~ <br /> <br />• <br />East A~fine .4rea Ou[(et Ditch <br />The ditch is designed for the 100 year - 24 hour event peak flow using the STORIvt program <br />developed by the technical branch of the Office of Surface Mining. The design is given below. <br />100 year - 24 hour precipitation: 2.4 inches <br />Curve Number of Site: (assuming worst case acreage disturbed at any one time) - 15.8 acres <br />disturbed porous gravel: CN = 79 <br />time of concentration path: 1 160' long, 50' drop, short grass pasture <br />Using these inputs, the STORM program produced the following results: <br />Project Title = Carol <br />WATERSHED HYDROGRAPH <br />Inflow into structure ~ <br />Structure type: <br />Ann Permit East Mine Area Outlet <br />1 <br />Null <br />-- Watershed data for watershed # 1 <br />Curve number = 79.0 <br />Area = 15.8 acres <br />Hydraulic length = 1160.00 Feet <br />Elevation change = 50.0 feet. <br />Concentration time = 0.22 hours <br />Concentration time type = SCS Upland Curves <br />Unit hydrograph type = Disturbed <br />-- Total Area <br />= 15.8 acres <br />-- Storm data <br />Total precipitation = 2.4 inches <br />Storm type = SCS Type 2 storm, 24 hour storm <br />Peak Discharge = 10.24 cfs <br />Discharge volume = 1.02 acre ft <br />The resulting peak flow is 10.24 cfs. The ditch will be a trapezoidal ditch of 2% grade and bottom <br />width of 3.0 feet. Sideslopes will be 2.OH:1.OV and the total depth will be 2.0 feet. Freeboard will <br />be l.0 feet. Using a Manning's n of 0.025 for coarse gravel lining, the ditch is capable of handling <br />Carol Ann Permit CDMG Application <br />26 <br />