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Memo to Steve Renner Fruits Highwall Stability page 7 instability of the Fruits mine highwall. The bench configuration on these older photos is not representative of the existing bench. The facial surface of the angle of repose bench face does evidence some raveling, debris calving and possible small rotational slumping. My examination of the 1990 and 1993 oblique stereographic pairs also detected no evidence of any rock highwall or natural slope instability. The 1990 reconstructed bench faces continues to display signs of raveling, debris calving and downhill spoil cascade. However, the 1993 partially reclaimed portal bench face shows no signs of instability. It is interesting to note that the 1990 oblique photographs show subtle evidence of natural exposure of the aubcrop of the Cameo seam in the incised valley approximately 1J2 mile west of the Fruits portal bench and highwall. There is also an obvious area of oxidation characteristic of a natural outcrop coal burn. Combustion of coal at outcrop where it is exposed to lightning strike and grass fire ignition is common in this area. The thin natural talus cover of the exposed coal seam aubcrop occasionally allow the coal seams to be exposed along the Book Cliffs. Because of their prominence it ie more common for the subcrop to be detectable on the resistant linear ridges. Recent Controversy In 1990 a reclamation plan submitted by American Shield Coal Company was approved by the Division. The operator subsequently affected the approved plan. The portal bench fill was excavated to create a more natural "V-shaped" valley fozin along the central axis of the fill. The material excavated was used to backfill the coal seam outcrop along the back wall of the portal bench pocket. A wedge of material was placed against the foot of the highwall to cover the exposed coal seam. The surface of the bench was then topsoiled and reseeded. The OSMRE subsequently expressed a concern regarding the unbackfilled exposure of the coal seam along the sidewalls above the portal bench. The Division issued a notice of violation to American Shield Coal Company in September of 1991. As steps to abate the violation the operator was directed to either submit an acceptable revision and complete the work or to obtain an appropriate variance under steep slope variance from AOC. In September of 1993 the Division amended the NOV to direct the operator to backfill the bench to completely eliminate the highwalls by December 14, 1993. In response, the operator contracted with Greg Lewicki to demonstrate that the required backfilling,would result in an unstable reclaimed configuration.