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16 - i <br />section in soils is shortened; this solution would increase the ~ <br />hei ht of the ortal cut. Potential stabilit ~ <br />g p y problems related <br />to a high portal cut. might be severe if the cut is close to the <br />steep slope above the bench. <br />The tunnels can significantly contribute to dewatering the ~ <br />area behind the portal. However, if they were fully lined with <br />an impermeable liner, they would not function as drains. We ~ <br />recommend that provisions for drainage into individual ttmnels ~ <br />are made so that effective drainage of the area can be enhanced. <br />I.t tan be expected that the tunnels will practically replace <br />the drainage systems which would be installed earlier. <br />3.3 ACCESS ROAD ~ <br />I <br />The proposed access road below the mine bench will be con- ~ <br />strutted partly within the landslide area. The design and con-• <br />struction of the section within the landslide have been di- ~ <br />cussed on numerous occasions with the representatives of Merrick <br />and Company. We have recommended that the necessary earth work ~ <br />be kept to a minimum so that high cuts or fills are avoided. ~is~ <br />is difficult within the road section immediately below the pro- <br />posed bench where the road alignment traverses a s*_eep natural ~I <br />slope. ~ <br />' Because of the steep slope gradient, cuts or fills cannot <br />~~' be constructed without appropriate retaining structures; it can <br />~ be expected that soil thickness on the order of 20 feet or more <br />will be encountered, and soil cuts are not Feasible. <br />A typical cross-section of the road within this section <br />will include a cut supported by a retaining wall and a fill <br />supported by another retaining wall. In order to evaluate the <br />stability of such a cross-section, we have performed several <br />stability analyses assuming the same soil properties as those <br />ao»no.ocws~ar..c.c <br />