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11111 <br />. Current thinking is that in this area no sediment was deposited during that period. <br />That is, for 500 million years, only erosion occurred. This is what is called the <br />Lipalian Interval, when most of the planet was nearly leveled and essentially no <br />mountain building occurred anywhere. <br />The granite is also behind the north and middle peaks. It has been mined in <br />the upper portion of the middle peak primarily to create the appropriate topography <br />on that mountainside. In the previous plan, the entire southwest corner of the <br />permit area, represented by a large hill of granite, was to be mined. That has now <br />been removed from the plan, leaving only a small amount of low-grade granite to be <br />removed mainly for topographic blending purposes. <br />We measured the orientations of the fractures in the more intact granite <br />exposed in the cuts in the layback area on the north and middle peaks. The fracture <br />orientations varied widely, however two sets of east facing fractures were found. <br />The first set had dip orientation within a few degrees of 90 degrees east with dips of <br />between 65 and 80 degrees to the east, and the second had dip orientations <br />between 134 and 142 degree with dips of between 43 and 80 degrees to the <br />southeast. These fractures are generally oriented at steeper angles than the cut <br />slopes in the pit. Based on observations within the layback area the granite is <br />generally decomposed to the point of having little structure and having more of the <br />characteristics of a dense sand and gravel with and angle of repose of about 35 <br />degrees where it has raveled. <br />Structural Geology <br />The quarry lies within a fault-bounded block within the Rampart Range Fault <br />zone. The fault block has a lenticular shape in plan view, with primary east and west <br />bounding faults and secondary diagonal splay faults to the north and south, <br />forming the boundaries of the block at and near the surface. The orientations of the <br />faults with depth are not known and their surficial locations are generally <br />approximately known. The Rampart Range Fault zone is a recent expression of an <br />• ancient fault zone along the eastern edge of the Rocky Mountain Front Range. The <br />TRANSIT MIX AGGREGATES 11 <br />PIKEVIEW QUARRY SLOPE <br />CTLIT PROJECT NO. CS17341-125 <br />S:1CS17000-174991CS17341.000112512. Reports1CS17341-125-R1-Final.doc