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21 . Approximately 15-0 feet above the �7_ turf: . , _ sang szone cutcrop has <br /> prevented ditch excavation, and water has fio'wEd across and down the <br /> road, scattering rock and debris , and eroding rills down to and around <br /> the switchback below the RD-1 outfall . The ditch immediately above the <br /> RO-1 outfall was silted in, and the inside curve of the switchback was <br /> heavily rilled. <br /> 22. Between the RD-1 switchback and Culvert F-1 , the ditch was filled in, in <br /> many locations , and the road surface and fill slopes were rilled along <br /> most of the segment. <br /> 23. Between Culvert F-1 and the end of Road F, a distance of approximately <br /> 3 ,000 feet, the road is cut through steep outcrops of unweathered shale . <br /> Through this segment, there is essentially no road ditch due to <br /> deposition of scree from rock cuts and rock debris from steep erosional <br /> channels . In a number of locations , ditch excavation was precluded by <br /> solid bedrock. In several places , flows have run off the road in an <br /> uncontrolled manner, in some cases within pre-existing erosion channels <br /> and in some places causing new gully formation . Two gullies , apparently <br /> caused or significantly enlarged by road runoff are 20 to 30 feet wide <br /> and 10 to 15 feet deep. These gullies extend for several hundred feet <br /> down the steeply pitched shale slope to the north fork of Dutch Creek. <br /> Large sediment deltas extending into the flcodplain of the stream are <br /> apparent. Headcutting of these gullies has pinched the road width down <br /> to approximately 15 feet in two locations . <br /> Road E <br /> 24. As with other roads , the drainage ditch does not meet design <br /> configuration for much of its length , with some segments eroded , some <br /> segments silted in , and required riprap checks not installed. <br /> 25. In the vicinity of Sta. 43+00, rilling on the road sur'ace has led to <br /> fill slope erosion. <br /> 26. In the vicinity of Sta. 40+00, a landslide has impacted the road , as well <br /> as a lower road segment between 10+00 and the RO-1 N ditch outfctll . The <br /> slump scarp extends into the road fill and has reduced the effective road <br /> width at Sta. 40+00 to approximately 15 feet. The slide body is <br /> approximately 20 to 25 feet wide at the upper end and approximately <br /> 100 feet wide at its lower end. <br /> Debris from the slide has flowed across the read between approximately <br /> Sta. 5+50 and Sta. 7,00. The road in this section has been <br /> re-established through the slide debris , but a high level of maintenance <br /> is required to maintain proper drainage. Ditch maintenance and <br /> dcwncutting trigger slougnage or material from the toe of the slide into <br /> the ditch. In string and early summer, there is extensive drainage from <br /> seep: in the slide bcd%/, and sur icial material from the slump has flowed <br /> in a sacurat_d state across one read and directly into the Ncrth Fork of <br />