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The geotechnical specifications are found in Volume 6, prepared by Golder Associates, <br />consultant to the operator. This appendix presents the results of geotechnical <br />investigations, stability analyses and detailed engineering design for the portal bench cut <br />and fill and the accompanying haul road. The stability analyses are based upon <br />projected cut slope configurations and material mechanical properties obtained from <br />material sampling and laboratory analyses. <br />Stability analyses were completed for cross sections chosen at road stations believed to <br />represent potentially critical slope stability situations along the proposed upgraded haul <br />road. As a result of this slope stability analysis, the operator amended its original <br />proposed road cut slope configurations to use a Hilfiker wall, or equivalent, retention <br />system. The retention system will be utilized as depicted on Sheet 7 of 10 of [he Golder <br />Associates report, entitled "Haul Road (1)," to reduce the unretained cut slope heights to <br />a maximum of 30 feet. The Hilfiker treatment will be applied between road design <br />stations 29+50' and 36+SO'. Unretained cut slopes will not exceed a maximum slope <br />gradient of 1.25h:1.Ov (horizontal to vertical) unless an appropriate slope stability <br />monitoring program has been approved by the Division. With an approved monitoring <br />program, cut slopes will be allowed to reach a maximum slope gradient of 1.Oh:1.Ov <br />(horizontal to vertical). The stability analysis determined a minimum operational static <br />slope safety factor adjoining the upgraded haul road of 1.72. <br />The operator will remove and reclaim that portion of the haul road constructed to <br />connect the existing public access road to the proposed portal bench embankment across <br />East Roatcap Creek (design plan road Station 32+50' to 38+50'). In addition, the <br />operator will partially backfill the road cut slopes during reclamation in order to narrow <br />the road from an operational width of 26 feet to a width of approximately 15 feet, <br />similar to that of the preexisting access road. This partial backfill will provide buttress <br />to the retained cut slopes of the haul road, increasing their static slope safety factors. <br />The ford of an ephemeral stream with a watershed of at least one square mile was <br />approved by the Division since it would not seriously alter normal water flow, <br />contribute to sediment load, or cause adverse affects to fish or wildlife. The ford is <br />located on East Roatcap Creek where the BLM road, used to access the west mine fan <br />facilities, crosses this creek. <br />The R.O.M. stockpile haul road was consttvcted between May 10, 1976 and May 4, <br />1977. Minor Revision No. 66 formally included this haul road into the permit <br />application. The road had been constructed on mainly fill material. It was surface treated <br />with 12 inches of gravel in June of 1992 gravel and certified. The R.O.M. haul road will <br />be reclaimed after [he closure of the mine. <br />The haul road leading to the West Ridge Waste Pile was constructed in 1984 and had <br />originally been designated as an access road. However, the road was upgraded to a haul <br />road and a certified relevant showing, pursuant to Rule 4.03.1(1)(d)(ii) was submitted as <br />part of the permit renewal no. 3 adequacy. The certification states that, with the <br />information that is available, the haul road meets the specifications of Rule 4.03.1, <br />26 <br />