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2.05.3 <br />shaft is approximately 310 ft. in depth and enters the South III Suh-mains. The top 20 ft. of the <br />shaft is lined. A steel housing with explosion doors is constructed over the shaft. A concrete <br />foundation supports the fan, housing, evase and upcast structures. <br />The shaft site is located on a natwal, nearly flat bench. No surface or groundwaters are evident. <br />Based on the stability analysis completed on the water tank, no instabilities of the shaft site aze <br />anticipated (refer to the Water Tank Foundation Design in the Mine Facilities Appendix, Volume <br />8A). <br />The shaft site is located on BRL and Bureau of Land Management (BLM) Properties within coal <br />lease C-37210. The light-use road and powerline is located on BLM property. The 7.2 KV <br />power line extends approximately 1,850 ft. from the existing West Ivfine fan transformer to the <br />shaft fan. Approximately seven 40-foot poles were erected. The poles are located as close as <br />possible to existing roads. A small tracked vehicle was used to install the poles so no additional <br />access construction was required. <br />A light-use road is utilized to access the shaft site to inspect the fan daily. As shown on Map No. <br />8-7, the road was constructed from the material storage area north of the West Mine <br />sedimentation pond, following the contour and connecting with an existing drill road. This road <br />• segment is approximately 1,300 ft. in length and 12 ft. in width. A short segment of <br />approximately 200 ft. was constructed from the water tank site to the shaft site. The overall grade <br />of the road is approximately 9.5 percent. The road was seeded with grass and fort species from <br />the permanent approved seed mixture and vehicle access is restricted. <br />Monitoring personnel now access the fan by utilizing apre-existing light use road located to the <br />north of the west mine azea. <br />After consultation with the Division and CHZM Hill engineers, the Operator proposed the <br />following, in order to repair a cut failure at the north side of the west portal cut, m order to <br />reduce the risk of future failure, approximately 2,600 yd' of slumped material was removed, as <br />shown in the four cross sections, figures 2,3,4 and 5. The excavation will widen the intermediate <br />bench from 5 to 15 feet, and flatten the slope above the bench to 2(ITj:I(V). Material will be <br />removed by access along the bench, or by pushing the material off the bench to the bottom of the <br />cut, where it can be picked up. Prior to removal of the slide material, a trench was excavated <br />through the slide to verify the depth of the shear surface. <br />To accomplish the slope reduction, it was necessary to move approximately 3,300 yd' of topsoil <br />from the existing topsoil stockpile above the cut, and place it on the north and west sides of the <br />stockpile. The final slopes on the topsoil stockpile are approximately 2.5(H):1(V). The topsoil <br />ditch on the south will be relocated into the slope on a bench 10 ft wide. The other topsoil <br />• ditches were extended or relocated as necessary to accommodate the stockpile. <br />TR-32 - 12 - 9/99 <br />z/ s/ o u <br />