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Memo to Steve Renner Fruits Highwall Stability page 2 landform consists of an erosional cliff exposure of the Mesa Verde Group. This distinctive regional landform extends for several hundred miles north from Grand Junction, Colorado in a gentle arc to the north, west, and then south to Price, Utah. In the Fruits area the cliffs rise from a topographic break in gradient at approximately 5,500 feeC amsl to a hogback ridge crest at approximately 6,650 feet amsl. The portal bench is situated 220 feet up the cliff face in the Mount Garfield Formation. The lower surface facilities site at the base of the cliff at approximately 5,450 feet amsl at the upper extent of a gentle pediment ramp which rises gradually from the valley floor of the Colorado River. Locally, the bedrock attitude dips approximately 5° to 10° to the north-northeast, into the cliff face. Both the Main Cameo and Upper Cameo seams have been mined on the property. Regionally, the two seams are separated by interburden varying from zero to 80 feet in thickness. The stratigraphic section from approximately 100 feet below the Cameo seam to the local ridge crest is supported by cliff-forming sandstones and siltstones. The Book Cliffs are not a single precipitous cliff interval, but in contrast to the gently rising pediment at their feet, they represent an impressive series of ledges separated by steep talus slopes. The portal of the Fruits mine.ia located near the bottom of a 180 foot thick, ledge- forming predominantly sandstone unit. On the back side of. the topographic treat, a gentler dipslope extends to the north into Coal Gulch. The face of the Book Cliffs ie regularly punctuated by steep sided linear valleys. These linear incised valleys occur at a relatively - consistent- spacing of between. 1,250 and 1,500 feet, oriented perpendicular to the cliff face. The valleys are separated by regular prominent spines. Historic Development of the Portal Area The portal of the Fruits Mine occupies the thalweg of one of the incised linear erosional valleys. The portal bench was created by excavating the accumulated talus and weathered debris beneath it to form a face-up pocket. The excavated material was spoiled into the valley below the portal elevation to create a portal bench fill. The portal excavation was enlarged by excavating additional material from both the east. and west sideslopes of the narrow linear valley, resulting in cut slopes forming three sides of the portal pocket. This additional excavated material was added to the bench to increase the working area of the bench. This pocket was enlarged in the early 1980s. The operator was required to place the additional material in compacted lifts at a lower facial angle.