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~; bars was accomplished with a small track dozer or track mounted backhoe that was <br />also used to remove the power poles and conductor. In the portal area, the trail was <br />re-established by creating a four foot wide nearly level bench along the western edge of <br />the portal bench. The livestock trail was sloped about 2 percent toward the drainage to <br />allow for proper run off and to minimize erosion. Water bars were also created as <br />shown on Figure 3.1-7. The reclaimed trail will allow access of cattle to the main <br />drainage behind the portal area where access to areas above the portals by cattle is <br />available. <br />Slope Stability <br />The slopes analyzed at the mine site were at Station 49+25 and 51 +00, shown <br />on Figures 3.1-4 and 3.1-7. Cross sections of these areas are shown on Figure 3.1-9. <br />The soil in the area of the mine site is the same as the colluvial soil found along the <br />upper portions of the mine road. This soil is a highly cohesive clay, 1,300 PSF; with a <br />relative) low an le of internal friction 15°• and a densit of 130 Ib/ft3. <br />Y 9 y <br />The first line analyzed is along the top of the ridge created when the slope is <br />reclaimed, Station 49+25. The analysis of the first line indicated that the existing <br />configuration has a stability factor of 1.346. Analysis indicates that the stability will be <br />improved to 1.439 upon reclamation. <br />The second area analyzed is located approximately half way between the first <br />line and the existing roadway portal near the sediment trap. This area was chosen for <br />analysis since it is the area where a slide developed when water draining from the road <br />which existed prior to mining above the slope saturated the slope and caused a slide in <br />the area. The slope has been stable since the water running down the road was <br />directed back into the natural drainage with a water bar. This will also be the tallest <br />reclaimed slope after the area has been recontoured. Coal from the Loma Loadout was <br />also used to backfill near the existing portals as is shown on Figures 3.1-4 and 3.1-7. A <br />representative sample of the coal in the backfill was sent to Lambert and Associates for <br />triaxial shear strength tests. The coal material has a cohesion of 3psi or 432 psf, a <br />~~ <br />TR-23 3-13 12/07 <br />