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-13- • results of the sedimentation analysis are summarized in LRCWE Table 3, Required Sediment Storage Volumes. LRCWE Plate I, Sedimentation Ponds, Energy Mines No. 1 and 2, and Eckman Park sets forth the pond volume for each site. The pond volume includes the required sedimentation volume and the routed 10-year 24-hour inflow flood. FLOOD ROUTING The flood routing for all ponds except A assumed an initial water surface at the required sedimentation level. This is the elevation of the lowest set of holes in the riser pipe. For Pond A, a permanent pool elevation of slightly more than the required sedimentation level was assumed because the reservoir will also store 27 acre-feet of irrigation water. Section 816.46 (h) requires that the reservoir be cleaned when the sedimentation reaches 60% maximum of the required sedimentation volume. However, after the first significant inflow, a permanent maximum pool elevation equal to the required • sedimentation level will develop as this is the elevation of the lowest set of holes on the riser. Actual flood routings were computed for the 10-year, 100-year and Pty inflow floods for Pond A, and the 10-year floods for Ponds D, E, F, and G. The actual flood routings for the 10-year floods for these reservoirs were used to determine the elevation of the crest for their risers. All of the other ponds have a Type 3 riser which limits the outflow rate to such an extent, that the entire 10-year inflow volume was assumed to be stored for the pur- pose of setting the riser elevation. To confirm this assumption the 10-year 24-hour inflow flood was routed for Pond K. INTERCEPTOR DITCHES Interceptor ditches were used to modify the natural tributary areas to var- ious ponds in order to maximize the use of favorable ponding locations. The ditches are located in plan view on Energy Mines No. 1 and 2 Hydrology (EFC . Map 13). They are identified with '_etters which correspond to the pond Leonard Rice Consulting Water Engineers. Inc.