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1 approximately 3 ft. Joint surfaces are typically tight and appear fresh to slightly weathered. ' Joints are typically discontinuous. Three dominant secondary joint sets were mapped on Benches B, C, and D and are provided ' in Table 1. Two of these joint sets dip steeply to near vertical and strike orthogonal to each other, dipping into and out of the mining face. Vertical presplit blasting holes combined with preferential fracture propagation along these joints, cause the final highwalls to be relatively ' vertical. The other secondary joint set strikes north/south and typically dips 35° to 60° to the east. Spacing of joints in the secondary joint sets typically range from 0.5 ft to 10 feet. Joint surfaces are typically tight and appear fresh to slightly weathered. Joints are both continuous ' and discontinuous. The following subsections describe particular characteristics and slope conditions of specific ' regions of the quarry. A. East Side The overall slope appears stable. There are localized areas of instability on individual benches. These typically occur where the primary joint set strikes parallel with the slope and daylights out of the highwalls, and where secondary joint set(s) occur and serve as ' detachment planes. Localized wedge and slab slip surfaces were observed on the outside edges of individual benches. These slip surfaces are infrequent and are relatively small, generally less than 10 feet in length. These features are as expected for the highwall and only cause localized operational inconveniences. Although most are small, one slip surface approximately 40 feet long and 80 feet wide was noted at locations K and L (Figure 1), resulting in the loss of most of the bench, but appears to be limited to that bench. This area ' will be under water once reclaimed. Two random (tertiary) joints were identified on the east side (Figure 1, locations G, N). ' These random joints are continuous and are orientated sub-perpendicular to the slope and dipping out of the slope. These random joints coincide with foliation in the rock mass and are visible for 200 ft in length along the highwall. These joints showed no apparent ' movement during blasting of lower benches. The condition of the rock mass in the vicinity of Benches C and D on the east side is ' "competent". In general, the competency of the rock mass at the lower benches is better than at the upper benches. This is the result of a lesser degree of weathering, especially along the primary joints, and the presence of the iron-rich rock. The iron-rich rock has a jointing pattern different from the gneiss, and tends to terminate the unfavorable jointing in the gneiss. ' Based on the rock mass conditions observed, the condition of the rock mass of the new final highwalls developed during 2000 was observed to be better than the conditions used as the t baseline (as defined in the Observational Method) for analyses of the east side. Twenty-six surface surrey points (numbered 2001 through 2026) were established to monitor ' the effectiveness of the repair of the unstable slope on $ench 6 and 7. Positions of the surface survey points have been determined by surveys conducted in March and May 1997, March 1998, August 1998, August 1999 and August 2000, which provide data to assess the performance of the slide repair during 1998. Several survey points have been damaged by mining activities. All the remaining points exhibited 0.14 ft or less of displacement from ' G ~PROIECTSVO?00 Mormm~ Quarry~008~?(IOOtr<pon0000 geoiechmcal aJdendum doc