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occasional banding visible along the foliation of the rock. The term foliation <br />refers to the realignment of minerals into a parallel orientation as a result of the <br />intense heat and/or pressure of metamorphism. The rock mass tends to be <br />weakest along the foliation planes, which ultimately results in a discontinuity set <br />parallel to the orientation of the foliation. The foliation orientation is the most <br />prominent discontinuity set identified in the quarry and is readily visible in the <br />east and west walls. The rock foliations undulate in a synclinal and anticlinal <br />fashion, with noticeable variation in dip angles across each wall (Photo 1). <br />A notable geologic feature near the site is the Golden fault, which runs <br />approximately north-south and forms the eastern margin of the north-northwest <br />trending hogback immediately east of the quarry property. A mapped reverse <br />fault is located within the quarry property and constitutes the boundary between <br />the metamorphosed Precambrian bedrock (to the west) and the Pennsylvanian <br />sedimentary rocks (to the east) (Smith, 1964; Scott, 1972). The quarry property <br />straddles this boundary, with the majority of the processing plant and the entire <br />asphalt plant located east of the fault (Figure 3). The bedrock material east of <br />the fault is dominantly composed of upturned sandstones and shales of the <br />Fountain Formation (Scott, 1972). West of this fault, the material is typically <br />mapped as migmatitic, quartzo-felspathic gneiss with intrusions of granitic <br />pegmatite veins (Scott, 1972). <br />Mapped within the main pit of the quarry are two approximately east-west <br />trending faults that have been exposed as the quarry has been excavated. One <br />of the faults is located in Jackson Gulch, and has been informally named the <br />Jackson Gulch fault. It has been difficult to mapping the surficial trace of this <br />fault because the area has been extensively modified, and fresh exposures have <br />been covered up by backfill material before measurements could be made. The <br />second fault is unnamed and is exposed in the east wall and west wall of the <br />main pit and ranges between 20 to 50 feet wide. This fault was also mapped by <br />-5- <br />