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where sideslopes caru~ot be reduced. The natural hillslope in the area <br />• between Stas. 48+00 and 52+00 is approximately 3h:ly. In order to reduce <br />the amount of cut slope and "catch" the hill as soon as possible, the cut <br />slopes have been designed at 1.5h:1v. <br />The possibility of constructing a French drain and/or adding another <br />culvert at 59+00 was investigated. The existing design calls fora 36" <br />diameter culvert >n that location (see Attaclvne~tt 2S for evaluations). <br />The Headwater to Depth ratio indicates that as a result of the 10-year, <br />24-hour precipitation event that the crater will rise 0.6 feet above the <br />top of the culvert. The embankment at this location is approximately 20 <br />feet high. That results in 3.6 feet of water, ilcq~ounding for a short <br />duration against the bottom of this fill. Proper sloping and grading the <br />fill towards the culvert will prevent water from standing at the tce of <br />the fill and therefore this location does not warrant an additional <br />culvert or French drain. Both ends of the culvert will be rip rapped to <br />prevent scouring around the inlet and outlet. A combination of keying in <br />the embankment to stable material and Mirafi to increase stability will <br />be used in this section of the road. <br />Sta. 64+00 to 76+00 <br />The remainder of the road alignment traverses areas mapped as mug, Qsg, <br />and Kwfl. This portion of the road will basically be constructed on <br />grade, with a slight elevation to maintain water control, snow removal, <br />etc. An area mapped as Qug exhibits scarps and hummocJcy ground. This <br />area lies to the east of the creek bed. The road will not contribute to <br />• further instability of this area. <br />CORRDCPIVE MEI7-IODS <br />If during or after construction, slope failure initiates, a number of <br />remedial actions will betaken depending on the nature of the failure. <br />Localized sloughing, as may be the case near Stas. 47+00 to 52+00 will <br />have to be repaire3 by removing loose material, filling aril tamping <br />cracks. Another possibility is covering the slope with some type of <br />impermeable membrane to prevent infiltration. If used, this would be a <br />temporary measure to prevent further slope saturation until drainage <br />patterns could be established. <br />It appears that this area could exhibit a maintenance type problem. The <br />shale, claystone bedrock may ravel by the weathering process alone. In <br />comparison, in the cut slope (Hole 4) at the Pond 006 slide area e:dribits <br />nearly the same characteristics as Holes M and P with regard to density, <br />passing the No. 200 Sieve, Liquid Limit and Plasticity Index. Since <br />the repair operation was conducted, this slope has not been a maintenance <br />problem. The regraded slope near Pond 006 was 2H:ly whereas these will <br />be somewhat steeper at 1.5H:1v. <br />The other major area of concern will be near Sta. 60+00. The road <br />esnbanlonent, according to stability analysis, will be stable. The road <br />will not cause additional instability problems to arise within this <br />drainage area. That is not to say that these slopes may not fail on their <br />own. If failure does result, and as a result of the failure, this causes <br />• road failure, which could result in problems with reclamation, then the <br />following corrective methods would be taken. At the present time the <br />10 <br />