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and stop signs will be placed on both sides of the haul road at any intersection. These approaches will be similar to those constructed along the tie-across haul road. Haul Roads A and B are designed with appropriate ditches, grades, and culverts to control erosion and runoff. Exhibit 13-9, Typical Haul Road Details and Figures 13-1, Typical Road Embankment and 13-2, Typical Road Cut, illustrates typical cut and fill sections of the haul roads. The proposed haul roads are designated as Haul Road B Extension, Haul Road C and Haul Road D. The proposed locations of these roads are shown on Exhibit 12-1, Operations Plan, while the designs for each proposed road are presented on Exhibit 13-11.3, Proposed Haul Road B Extension; and Exhibit 13-11.4, Proposed Haut Roads C and D. The majority of these proposed haul roads will be built prior to the time mining commences. However, some of the haul roads will be extended through the spoil and road construction will progress along with the mining activity. Final reclamation of these roads will occur as the areas are mined out or as the roads are no longer needed. The proposed haul roads were designed for the anticipated volume, weight and speeds of vehicles to be used. The proposed haul roads will be constructed in the same manner that the existing haul roads were constructed. The proposed haul road width, curves, and base material will be consisted with the existing haul roads and ramps. SCC has been hauling coal over the existing haul roads for over two years without any operational problems. SCC doesn't anticipate changing hauling equipment during the remaining life-of-mine, therefore it is SCC's opinion that the proposed designs will be adequate to handle the anticipated traffic load. Haul roads will be located, to the extent possible, on ridges or along the most stable available slopes • to minimize erosion. In the unlikely case that a haul road must be routed across a portion of an unconsolidated surficial landslide, SCC will either remove the surficial, slide material or conduct a geotechnical investigation to determine the characteristics and extent of any possible instability. This circumstance will be identified in the field prior to actual construction and a qualified engineer will determine if any changes in construction methods or design are required. Haul Road D contains sections that are steeper than 10 percent and at the request of the Division as stability analysis was performed for the associated cut and fill slope. The stability analysis indicates a static factor or safety of 2.1 for the fill slopes and 2.6 for the cut slopes. The results are included in Attachment 13-18, Haul Road D Stability Analysis. The area of proposed Haul Road "B" Extension was mapped as Qols -Quaternary unconsolidated older surficial landslide deposits, from aerial photos Isee Exhibit 6-1, Site Specific Geology, and Exhibit 12- 1, Operations Plan, for locationsl. Based on this mapping and physical investigations/observations, the mapped surficial materials appear to have already slid and are now in a stable configuration, otherwise there would be evidence of recent movement. SCC removed and stockpiled the topsoil from this area in the Fall of 1998, thereby unloading and removing any potentially unstable material remaining, and has not observed any signs of further instability to date. A physical investigation of the disturbed areas was conducted in May of 1999 and no indication of movement or instability was observed • except in one minor area at the nose of a small ridge where a minor tension crack was observed. This minor tension crack is approximately 20 feet in length and varies from X to 2 %. inches in width. 12 Revised 5/99