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curve, 12 -hour storm was used with the storm duration forced to be 8 hours in an effort to best <br />match the original work. Peak flow results for this analysis as compared to the original design <br />analysis are summarized on Table 2: <br />Table 2 PMF Peak Flow Comparisons: Original Desiqn and Current Analvsis <br />Catchment Area <br />Designation <br />Original Design <br />cfs <br />Current Analysis <br />cfs <br />_ Area A <br />4725 <br />2668 <br />Area B <br />2497 <br />1825 <br />Area C <br />1084 <br />1002 <br />Area D <br />1498 <br />1030 <br />Area E <br />1875 <br />909 <br />For purposes of South Diversion Ditch peak flow evaluation only the peaks from Areas A, B and <br />C are relevant. For Areas A through C the ratio of the current evaluation peak flow to the <br />originally computed peak flow varies from 0.56 to 0.92. A review of the original methodology <br />did not enable us to confirm the basis of the earlier peak flow determinations. The values <br />previously derived appear to be overly conservative being both beyond any peak factor option <br />available in HydroCAD and beyond normal peaking factors typically found in the literature. <br />Accordingly the hydrographs derived as part of this review will be used for channel capacity <br />analysis in HEC -RAS modeling. Hydrographs derived are presented in Figure 15. <br />,atltla <br />woa o <br />ima - <br />\soao <br />san a <br />Dtl � <br />tlaa <br />Figure 15 South Diversion Ditch PMF Inflow Hydrographs <br />San Luis Project Miller Geotechnical Consultants <br />Tailing Dam Data Report 28 February 2014 <br />