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SECTION 1 - HIGH SOIL CUT, ROAD <br /> GENERAL: Excavated in colluvial soils; no rock outcrops. Excavated <br /> in steep slope , often up to 450. Lower cuts are usually <br /> flatter. Because of excavation procedures , highest cut <br /> portion is occasionally very steep, up to vertical . <br /> STABILITY AND OTHER PROBLEMS: General (overall ) stability is <br /> usually satisfactory; it can be reasonably assumed that <br /> F.S. of most slopes is slightly above unity (say, F.S. _ <br /> 1. 1) . Sloughing of steeply undercut crest is common. <br /> Erosion problems are frequent. Ground water seeping out of <br /> the cut slope may contribute to local instability or <br /> increased erosion. Eroded material from the cut face ac- <br /> cumulates in the ditch or at the cut toe if there is no <br /> ditch present. <br /> RECLAMATION CONCEPT: Flatten the cut portion in the crest vicinity <br /> to create flatter and uniform slope. Place a buttress at <br /> toe of the cut. Build a ditch at buttress toe. Leave <br /> enough space between outside edge of ditch and crest of <br /> fill ( i f any) to accommodate light use road , at least 15 <br /> feet wide . Vegetate . <br /> METHOD OF RECLAMATION: Construct a pioneer road to the cut crest <br /> with minimum disturbance. Road necessary only for dozer <br /> and backhoe. Preferable location of road within the cut <br /> portion to be flattened. Clear vegetation, remove and <br /> store topsoil , if any. Push material from the crest area <br /> over the cut crest. Spread the material at toe of cut in <br /> lifts not exceeding 12 inches and compact by several runs <br /> of the tractor used for spreading. Excavate a ditch at toe <br /> of buttress; use triangular ditch cross-section. Contour <br /> surface of the flattened cut and of the buttress with a <br /> backhoe or front-end loader . Vegetate all surface of cut . <br /> ANALYTICAL CONSIDERATIONS. Assuming a current overall safety factor <br /> F. S. = 1. 1, evaluate the influence of : <br /> o Flattening the crest area to 45 - 40 - 35 degrees <br /> o Placing the buttress, slope 2 1, height of 10 - 20 <br /> to 30% of the total cut height <br /> o Analyze erosion effects of both these measures <br /> o Analyze need for riprap in ditch <br /> o Analyze size of ditch (standard sizes) <br /> PROPOSED LOCATION: C-Road , STA 126+00 to 132+00 <br /> 6 - <br />