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STATION 42+00 <br />This area on the road was chosen to analyze for stability because it is one of the <br />steepest portions of the road. The area has a history of surface sloughage throughout <br />the life of the road, but has not had any major slope failures. Unlike the previous area, <br />this area has highly cohesive soils that enhance the stability of the slope. Analysis of <br />the present configuration indicates a factor of safety of 1.305. The reclaimed <br />configuration using a moderately cohesive soil, 300 psf, shows a stable factor of safety <br />of 1.317 . Once again, analysis of just the backfill was performed indicating a factor of <br />safety 1.969. This slope should be stable after it is reclaimed as shown on Figure 3.1-8. <br />This area was essentially backfilled and compacted as anticipated in the stability <br />analysis. Therefore the calculated factors of safety should be valid. <br />STATION 47+00 <br />The next slope analyzed for stability is located just below the mine site as shown <br />on Figure 3.1-4. The area has also had a history of surface sloughage and has highly <br />cohesive soil. The cohesive soil contributes to a factor of safet of 1.363 for the <br />Y <br />present configuration, 1.370 for the reclaimed configuration, and 1.760 for the backfill. <br />The analysis indicates that the reclamation proposed will be stable. <br />This area was essentially backfilled and compacted as anticipated in the stability <br />analysis. Therefore the calculated factors of safety should be valid. <br />3.3.3 Backfill and Grading -Mine Site <br />Interim reclamation occurred prior to final reclamation of the mine portal bench. <br />Coal material was hauled from the Loma Loadout and placed at the base of the portal <br />bench cut slope during September and October 2001. The coaly material placed on the <br />Munger Mine bench was spread and compacted in compliance with 4.10.4(3)(a) and (b) <br />and such placement and compaction was inspected and certified by a qualified <br />registered engineer, in compliance with 4.09.1(11)(a) and (b). See the Mine Portal <br />Backfill Certification located in Appendix H. This coal material was covered with non- <br />toxic cover and seeded with a stabilization seedmix. The topsoil seedmix listed in <br />TR-23 3-11 <br />12/07 <br />