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1 In the expansion area, Gable (1968) mapped a third fault that also trends roughly east- <br />west (Figure 3). This fault was initially exposed during the 2006 investigation, and was <br />noted by a distinct pegmatite vein that is surrounded by decomposed weak biotite rich <br />gneiss. The fault was exposed in a temporary wall along the western margin of the <br />' expansion area, although accurate strike and dip measurements were not obtained due to <br />the high fracture density of the exposed material (Figure 3). <br />The granitic gneiss found in the quarry is generally hard and relatively competent. The <br />gneiss varies in color from grayish orange to dark gray, with occasional banding visible <br />along the foliation of the rock. The term foliation refers to the realignment of minerals into <br />a parallel orientation as a result of the intense heat and/or pressure of metamorphism. <br />The rock mass tends to be weakest along the foliation planes, which ultimately results in a <br />discontinuity set parallel to the orientation of the foliation. The foliation orientation is the <br />most prominent discontinuity set identified in the quarry and is readily visible in the east <br />and west walls. The rock foliations undulate in a synclinal and anticlinal fashion, with <br />noticeable variation in dip angles across each wall. <br />-4- <br />Lachet & Associates <br />a sr1INABF1 FNGINFrainc -9r P4NY