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1 ' At least two secondary joint sets are present, generally orthogonal to the primary joint set. In some cases, they cut through primary jointing and in some cases they terminate at a primary join[. These secondary joints typically occur at intervals of one to five ft. In general, ' secondary join[ surfaces are fresher and less weathered than the primary joints along foliation and do not typically exhibit the smooth schist or mica surfaces. 1 1 1 1 1 1 IJ I 1 1 1 1 Based on the conditions observed with the present exposures, the rock mass at the south end of the Central Quarry is still classified as "poor" in terms of the previously established baseline conditions. Note that the term rock mass incorporates the parent rock material plus jointing and other characteristics that influence behavior of the mass. This classification is based primarily on the low strength of the patent rock material, but also on the three joint sets and the low shear strength of some of the joints due to the smooth surfaces and weathering. This classification may change as addi[ional rock is exposed in this area. In general, the join[ orientations are neither advantageous nor detrimental to slope stability. Although the primary jointmg is often advantageous (i.e. dipping into the slope), significant variations exis[ and secondary jointing is often disadvantageous. Localized areas of instability were observed in temporary slopes and these conditions will continue to be monitored during further development in this area. Based on these observed conditions and on comparisons with baseline conditions for previous analyses, slopes at the south end of the Central Quarry are presently being excavated at an overall inclination of approximately 1H:1V or flatter. Furthermore, CAMAS intends [o mine 1H:1 V slopes in this part of the quarry as 40 ft highwalls and 40 ft benches. 5.04 Floor of Central Quarry Based on observed ground conditions and behavior of the exposed highwall txnches, the rock mass appears to be less susceptible to wedge and slab failure than rock located higher in the Central Quarry. 5.05 North Quarry In general, the controlling primary joint set observed to date has been along foliation of the gneiss and schist rock. it has been observed to strike approximately N75°W, approximately parallel with the ultimate orientation of the north wall, and dip 40 to 60 degrees south which is approximately perpendicular to the north wall slope. Another foliation joint trend striking generally north and dipping generally west as observed in the east side of the Central Quarry is also evident in the North Quarry. Folding and shearing has created a series of small syncline and anticlines from approximately 20 to 100 ft across. As a result of these anomalies, the strike of the foliation joints varies by 45 degrees either direction from the predominant strike direction and the dip typically varies by 20 degrees or more. Joint spacings typically range from several inches to approximately 3 ft. Joint surfaces vary grea[ly from fresh to highly weathered. Slick, weathered schist Zones are frequent. At least two secondary joint sets are present, often orthogonal with the primary joint set. These secondary joins typically occur at intervals of 1 to 5 ft. In general, secondary joint surfaces are fresher and less weathered than the foliation joints and do not typically exhibiC the smooth schistose or micaceous surfaces. ' G~PRWElT5CW00NOmmnQuarry~Opd~AruwLReponGmmcMiaLAEEeMUm~1998~98rprmukup.JCC Page 8