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Section 5 - 113 + 00 - 102 + 50 <br /> 1 ,050 foot segment from Culvert C-6 to RD-4 discharge. Cut and fill <br /> slopes fairly well vegetated along this segment except in areas of coal <br /> or shale outcrop . Discharge from RD-4 ditch outfall has caused severe <br /> erosion in the past and was subject of Notice of Violation C-90-050. The <br /> first 20 feet of the outfall has been riprapped pursuant to the approved <br /> permit. However, areas of severe downcutting have occurred in a <br /> 100+ foot segment of hillslope between RD-4 outfall and an ephemeral <br /> channel at the base of the hill slope . Gully reaches 15 feet wide by <br /> 20 feet deep near base of slope. Several additional eroded segments were <br /> observed between this point and the point where the ephemeral channel <br /> intersects the road below. <br /> Suggested remediatien is water bars at 100 foot spacing within Section 5, <br /> combined with log check dams keyed into gully sides and constructed at <br /> designed spacing throughout length of eroded segments . Note that check <br /> dams may not be warranted where gully has already been filled in with <br /> fallen trees and debris . This basic plan is suggested wherever severe <br /> erosion has occurred below culvert outfalls or road ditch discharge <br /> points (i .e. reduce flow volume via water bars , rolling dips , or <br /> additional culverts and stabilize gully with check dams) . <br /> Section 6 - 102 + 50 - 92 + 00 <br /> 1 ,050 foot segment from RD-4 discharge around switchback to RD-3 <br /> discharge. Road width around switchback below RD-4 is approximately <br /> 40 feet. Road at switchback and below should be narrowed and cutslope <br /> dozed to more moderate slope, with unneeded road surface ripped and <br /> seeded . <br /> At approximately sta. 95 + 00 drainage from Road C has been intercepted <br /> by an old exploration road and erosion has resulted at various points <br /> below where drainage has exited the exploration road. Accessible <br /> portions of the old road should be ripped, seeded and water barred , and <br /> significant gullies should be rocked or check dammed. The inside of the <br /> switchback at approximately sta. 94 + 00 might be an appropriate location <br /> for a dugout sediment trap. <br /> Some gullying 3-4 foot deep has occurred for several hundred feet below <br /> the RD-3 outfall , although the outfall itself has been rocked . A series <br /> of rock or log check dams to slow water velocities here would be <br /> advisable . <br />