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"poor" rock mass conditions. Localized areas of instability were observed in temporary slopes and these conditions will continue to be observed during further development in this area. Rock mass properties significantly improve with depth, due to higher strength parent rock, less weathered and more massive than the rock mass above, which is composed of low strength rock material with weathered and slick joint surfaces. The overall slope on the west side appears stable. Localized instabilities are infrequent and consist of relatively small loose blocks and wedges, generally less than ' 10 feet in length. These instabilities are as expected for the highwall and only cause localized operational inconveniences. The overall slope on the north end appears stable. Localized instabilities are infrequent and consist of relatively small loose blocks and wedges, generally less than ] 0 feet in length. These instabilities are as expected for the highwall and only cause localized ' operational inconveniences. 5.03 North Quarry The highwalls and benches in the north quarry currently extend along the East, North, and West exposures. Active mining is primarily in the central area of the bottom of the quarry and extending to the east and west. The mapped highwalls are along the north exposure (south- facing highwalls) and west exposure (east-facing highwalls). The rock type is primarily granite gneiss with mafic and felsic intrusions (felsite dikes and pegma6tes). For the west exposure Benches (1, A, B, and C) the foliation is generally dipping west into the highwall The trend and dip of the foliation varies locally due to several sets of anticline/syncline structural features in the rock mass. The primary joint set coincides with foliation of the rock mass. In general, the foliation dips in a west /southwest direction. Foliation orientation has local variations due to several sets of localized anticline/syncline structural features in the rock mass. Dip angle varies from approximately 10 degrees to 53 degrees. Mapping data is provided in Table 1. Spacing of joints in the primary joint set typically ranges from 0.5 ft to 2 ft. Joint surfaces are typically tight and appear slightly weathered to moderately weathered. Joints are very continuous in certain locations, and discontinuous in other locations. The most prominent secondaryjoint set strikes northwest to west (bearing N 25 W to N 82 W) I and is dipping from 58 degrees to 88 degrees. A less prominent secondary joint set strikes northeast (bearing N 13 E to due east) and is dipping from 24 degrees to 90 degrees (vertical). Joints may be dipping out of the highwall in localized azeas. Joint set information is provided in Table 1. Spacing of joints in the secondary sets typically ranges from 1 to 5 feet. Joint surfaces are typically tight to open and appear slightly weathered to weathered with some thin clay infill in the more weathered joings. Joints are both continuous and discontinuous. There are however, areas up to approximately 50 ft long where the rock mass is massive with no joints. L Additionally there are random joints with strikes and dips that were not observed to follow any pattern and can have any strike and dip. The overall west slope appears stable. Localized instabilities are limited to single benches and ' are evidenced by relatively small block and wedge shaped slip surfaces and raveling, generally less than 10 feet in length. These slip surfaces are as expected for the highwall and cause only localized operational inconveniences. The overall condition of the highwall above on Benches 1, A, B, and C in the areas mapped is "competent". For the north exposure Benches (B and C) the foliation is generally dipping southwest subparallel to the highwall. The trend and dip of the foliation may vary locally due to several 6