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Consultants, Inc. contains geo-technical conclusions regarding the stability of the proposed haul road corridor and recommendations for the construction of necessary road cuts and road fill embankments. The consultant's methodology consists basically of geological mapping of the affected area and observation of the performance of cuts adjoining the existing pioneer road, which was constructed roughly four years prior to this investigation. The geo-technical investigation determined that four basic soil or rock types are encountered along the road's alignment. While no major ordeep-seated landslides have occurred along the pioneer road, some shallow sloughing has occurred. By observing the cut slope gradients in areas of sloughing and correlating these observations with the four chazacteristic material types encountered, the applicant's consultant has developed recommendations regarding the maximum stable cut slope gradients for each chazacteristic material type (see Table 2.2-2 of the application). The consultant's methodology is sound in this analysis. Geo-Hydro's report contains the statement, "If our recommendations aze accepted, the cuts will probably be stable for the lifetime of the mine; sloughing will have to be expected and maintenance of the road will be required." The applicant's consultant has determined those cut slope gradients which should be stable during the operational life of the mine. In other words, the consultant has deduced what cut slope gradients for each chazacteristic solid or bedrock type encountered will assure a cut slope with a static slope safety factor which exceeds 1.0. The applicant's consultant did complete a mathematical stability analysis of the cut slopes or fill embankrrtents proposed to accommodate the enlazged haul road. Rule 4.03.1(3)(d)(ix) requires that no haul road fill embankment exceed a slope of 2h:ly unless the applicant demonstrates that the steeper proposed embankment will be stable. All fill embankments proposed within the application aze specified as having slopes of 2h:1 v and aze, therefore, in compliance with the permanent regulations. Rule 4.03.1(3)(c)(I) requires that no haul road cut slope exceed a slope of 1.Sh:ly in unconsolidated materials or a slope of 1/4h:ly in competent rock. Rule 4.03.1(3)(c)(I) does, however, allow for slopes in excess of the stated maximums. The rule states, "except that steeper slopes may be specifically authorized by the Division ifgeo-technical analysis demonstrates that a minimum safety factor of 1.5 can be maintained or if geo-technical analysis demonstrates that a safety factor less than 1.5 will not result in significant environmental harm or harm to the public health and safety." Close scrutiny of the applicant's proposed alignment and grading of the haul road corridor has determined that the cut slopes proposed at various locations between the design survey stations listed below exceed the allowed maximum slope gradients for cut slopes constructed in unconsolidated materials (see Figures 2.2-16) through 2.2-3). zo