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. This will allow access of cattle to the main drainage behind the portal area where <br />access to areas above the portals by cattle is available. <br />Slone 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 />relatively low angle of internal friction, 15°; and a density of 130 Ib/ft3. <br />The first line analyzed is along the top of the ridge that will be created when the <br />slope is reclaimed, Station 49+25. The analysis of the first line indicated that the <br />existing configuration has a stability factor of 1.346. Analysis indicates that the stability <br />will be 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 be used to backfill near the existing portals as is shown on Figures 3.1-4 and 3.1-7. <br />A representative sample of the coal in the backfill was sent to Lambert and Associates <br />for triaxial shear strength tests. The coal material has a cohesion of 3psi or 432 psf, a <br />angle of friction of 33o and a density of 82 pounds per cubic foot. The reclamation <br />stability cross section at Station 51+00 was reevaluated based on the coal placed in the <br />backfill and the strength parameters of the coal. The slope stability analysis was <br />performed using SB-Slope by Geosystem software. The slope stability analysis <br />considered numerous possible failure surface iterations to help identify the potential <br />theoretical slope stability. The stability analysis indicates a factor of safety of 1.78. <br />• Permit Renewal 3-13 08/03 <br />