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3-31 <br />L~ <br />• <br />UPPER ROAD <br />The upper portion of the road will require a more extensive reconstruction of the original <br />channels. In most cases, the original channel was filled during construction of the mine road. <br />Normally, the flow from the channel was diverted along the road in a ditch to a culvert which <br />directed the flow to the outslope of the road and then to the channel in the bottom of Munger <br />Canyon. Eight ephemeral drainages, labeled Athrough H in Fgures 3.1-2 through 3.1-7, cross <br />the road. The boundaries of these drainage basins are shown on Fgure 3.9.11 . Table 3.93 <br />shows the results of peak flow analysis for the drainages and the channel flow characteristics. <br />The reclaimed channels are shown in cross sections on Fgures 3.1-5 through 3.1.7. <br />The channels were designed so that the flow would not cause erosion by designing a <br />channel that will be wide enough so the peak flow will remain very shallow. Actually, most of the <br />channels will be excavated to the original channel, which will probably had channel bottoms <br />formed in the solid rock that forms the base of the road and the slope below the road. The <br />analysis of the channels took the "worst case" approach that the rock below the road would not <br />be encountered and the channels would be made of the soil in the area. <br />Rip•rap keys will be installed at the top and bottom of each reclaimed channel except for <br />those areas where rock outcrop is present. These rip rap keys will ensure that the entrance and <br />exit of each reclaimed channel will not erode during high flow . The rip-rap keys will be a two <br />foot wide by two foot deep slot dug into the channel bottom on both sides of the reconstructed <br />channel. The keys will be filled with one foot top size rip -rap. <br />MU <br />Volume I <br />12-18-96 <br />