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1 <br />' most prominent discontinuity set identified in the quarry and is readily visible in <br /> the east and west walls of the quarry; revealing a rock foliation that undulates in <br />' a synclinal and anticlinal fashion, with noticeable variation in dip angles across <br /> each wall (Photo 1). <br /> <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. Mapping the surficial trace of this fault is difficult due to the <br />extensive modification of the area and due to covering up the exposures after <br />' mining. The second fault is unnamed and is exposed in the east wall and west <br />wall of the main pit and ranges between 20 to 50 feet wide. This fault was also <br />' mapped by Gable, and strikes 260-270°, dips 80-85° to the south, and will <br />continue to be exposed as the pit deepens. <br />In the expansion area, Gable (1968) mapped a fault that also trends roughly east <br />' to west and may form a structural block that results in distinguishable <br />discontinuity clusters from the main part of the quarry. This fault is currently <br />-5- <br />