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The quarry consists of two separate mining areas: the main pit and the upper <br />level adjacent the main pit to the south. The floor of the main pit is <br />approximately 265 feet below the floor of the upper level. Figure 1 shows the <br />general layout of the mining areas of the quarry. <br />Notable geologic features include the Golden Fault, which runs north-south and <br />forms the interface between the Precambrian bedrock to the west and the <br />Cretaceous sedimentary rocks to the east. The quarry lies immediately to the <br />west of the fault in the granitic gneiss bedrock. The majority of the processing <br />plant and the entire asphalt plant lie east of the fault where upturned <br />sedimentary rocks (sandstones and shales) form the bedrock. Two relatively <br />minor faults, one known locally as the Jackson Gulch Fault and the other un- <br />named fault, are present in the main pit and trend east-west. The un-named <br />fault is visible on the east wall of the main pit and was also observed on the <br />current bench exposed along the west wall of the main pit. <br />The granitic gneiss found in the quarry is generally hard and relatively <br />competent. The gneiss varies in color from grayish orange to dark, with <br />occasional banding visible along the foliation of the rock. Foliation refers to the <br />parallel orientation that minerals assume as a result of intense heat and/or <br />pressures of the metamorphic process. The rock mass typically has a <br />preferential fracture mode along the foliation planes, resulting in a discontinuity <br />set that follows the orientation of the foliation. The foliation is readily visible in <br />the east and west walls of the quarry, which reveal that the rock foliation <br />undulates in a synclinal and anticlinal fashion with significant variation in dip <br />angles. <br />2002 Spec-Agg Annual Report Page 4 <br />