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<br />Area H is the active portion of the quarry which was being extended <br />vertically downward from about elevation 7400 at the time of the permit amendment <br />in 2001 to about elevation 7110 at the time of failure (Fig. 3). As part of the approved <br />amendment, a visibility barrier was left in place at about elevation 7200 on the east <br />side of the pit. This bench is used to stockpile aggregates after processing. The <br />processing plant is located at the north end of this bench area at about elevation <br />7220. The pit was being excavated to about elevation 7110 from south to north, after <br />drilling and blasting from a bench at about elevation 7140. The south end of the pit <br />was being actively backfilled to about elevation 7150, with higher benches to the <br />south. Area H was to eventually be backfilled to elevations between 7200 and 7225, <br />with a slope to the east. <br />For descriptive purposes of the operations and conditions of the quarry <br />prior to the failure, the west highwall is discussed with respect to three peaks along <br />the top as the north, middle, and south peaks. The area below and to the south of <br />the south peak had been reclaimed above about elevation 7250, with active filling of <br />the portion below about elevation 7150 occurring at the time of the failure. The <br />active blasting bench was located below the valley between the middle and north <br />peaks. The lowest active excavation portion of the pit extended from below the <br />valley between the south and middle peaks to below the valley between the middle <br />and north peaks. The area below the north peak varied from a bench at about <br />elevation 5170 feet at the north end to the current blasting bench at about elevation <br />5140 feet. The portion of the quarry where active mining was occurring was about <br />13.3 acres in area. <br />The area at the top and above the highwall at the middle and north peaks <br />was being excavated for decomposed granite for use in the reclamation. This area <br />is referred to in the plans as the layback area and covered about 12.4 acres at the <br />time of the failure (Fig. 2). The area within the affected land to the north of the active <br />portion, of which had been disturbed previously, had been reclaimed as had the <br />southern portion of the affected land. <br />TRANSIT MIX AGGREGATES 4 <br />PIKEVIEW QUARRY SLOPE <br />CTLIT PROJECT NO. CS17341-125 <br />S:ICS17000-174991CS17341.000112512. Reports%CS17341-125-R1-Final.doc