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Extension Instability Investigation, for documentation of existing conditions including photographs of <br />the area were topsoil was removed and the existing topsoil stockpile H. <br />SCC has not made a final determination relative to whether to establish the Haul Road B Extension, <br />begin mining in the area to the south, and then mine the "Neck Pit" on retreat or to mine the "Neck <br />Pit" area initially and establish the Haul Road B Extension in the resulting spoils area. Designs for <br />initial establishment of the Haul Road B Extension on natural ground have been prepared based on <br />available information and previous geotechnical evaluations and represent a "worst case" situation <br />relative to potential road grades and construction configuration. Key factors relative to the stability of <br />the Haul Road B Extension, if constructed as designed on natural ground, include the fact that the <br />mapped historic landslide area was composed of materials that had already moved and were in what <br />appeared to be a stable configuration, and previous removal of any potentially unstable surficial <br />materials during topsoil stripping operations in 1998. <br />If SCC elects to mine this area first and then establish the Haul Road B Extension on the resulting <br />spoils, road location and construction will differ from the design included in the permit. The additional <br />information required for design of the road in the spoils, however, including alignment, elevation, <br />material characteristics, and ground water conditions, will then be available. The advantages of <br />constructing the haul road in spoils would be that all surficial materials of concern would either be <br />removed (topsoil) or replaced in a stable configuration (overburden or spoil materials). If mining <br />• precedes construction of the Haul Road B Extension, SCC commits to design and construct this haul <br />road in the same manner as SCC's existing haul roads in mine spoil areas. SCC will complete and <br />obtain DMG approval of a haul road design prior to initiation of road construction. <br />A number of preventative measures can be instituted to "head off" or rectify potential failures. These <br />measures can include: <br />• Relocation <br />• Design <br />• Water management <br />Relocation. This project is unique in that only limited options are available to relocate the haul road. <br />However, SCC sees no logical reason io consider realignment options since all indications are that the <br />area is stable now. Relocating Haul Road B Extension, to be initially used to remove the coal from the <br />"neck" area of Section 17, is not practical or operationally feasible. Once the road has been <br />established for coal removal, it would provide no environmental or operational benefit to relocate it to <br />a different alignment. Conversely, it would require additional disturbance and potential revision of the <br />permit boundary. As everyone knows this requires significant time delays, which is not an option for <br />SCC. <br />Design. As shown on mapping and through observation, the "neck" area of Section 17 has had the <br />topsoil removed, thereby "unloading" the area which serves to reduce or eliminate further sliding. <br />9b TR-21 Revised 06/02 <br />