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11111 <br />• active surface flow during most of the year, which disappears below the surface a <br />few hundred feet west of the quarry. The other three drainages are generally dry. <br />The majority of the "Hole", below elevation 7200 feet, has been excavated <br />during a period of below normal precipitation after 2004. Appendix C contains a <br />summary of plots' precipitation data from 1997 to 2009 and data from 1948 to <br />present. However, in 2008 the precipitation during August and September was <br />about 9.3 inches, which was the wettest two month period since 2004. This two <br />month period of high precipitation likely increased the ground water levels in the <br />limestone within the quarry <br />Ground water levels are not known at this time, but they were likely relatively <br />high at the time of the failure based on the "steam plume" seen rising from the area <br />at the base of the main scarp a few days after the slide occurred. The ground water <br />levels have likely declined to a lower portion of the slide mass since the slide <br />occurred and opened fractures along its base area for ground water to flow <br />• through. Water flow into the storm water pond in the bend in the quarry road <br />reportedly increased shortly after the failure, but was not documented. <br />The water levels measured in the blast holes in the lower bench prior to <br />blasting have been erratic, with some holes having up to 10 feet of water and others <br />being dry. One sequence of blast holes at the south end was noted as dry during <br />drilling, but the holes were full of water prior to blasting. No water has been noted <br />in the bottom of the quarry on a consistent basis. <br />We believe it is likely that the western boundary fault is acting as a conduit <br />for ground water flow along the west side of the quarry. However, based on the <br />shale on the east side of the east fault, the east fault is likely acting as an <br />impediment to ground water flow. <br />• <br />TRANSIT MIX AGGREGATES 13 <br />PIKEVIEW QUARRY SLOPE <br />CTLIT PROJECT NO. CS17341-125 <br />S:ICS17000-174991CS17341.0 0 011 2 512. ReportslCS17341-125-R1-Final.doc