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<br />• <br />S ` Generally, the site slopes moderately to steeply down to the southwest towards Pond 16. The topography in <br />the failure area is highly variable due to the previous site grading, pond construction and debris flows. Due to <br />the steepness of the slope located above the head scarp we were unable to access this portion of the for this <br />investigation. <br />Field Investigation <br />Two field investigations have been completed for this project. The first field investigation was completed <br />from September 10 to September 23, 2008. During this investigation, six (6) test holes (TH-1 through TH-6) <br />and five (5) test pits (TP-1 through TP-5) were excavated within the slide area. A second field investigation <br />was completed on June 23, 2009. This investigation consisted of the drilling of five (5) additional test holes <br />outside of the slide area. The test hole and test pit locations are shown in Figure #2. <br />The test holes and pits were advanced to explore the subsurface conditions within the limits of the failed area, <br />as well as those situated above and to the east and northeast of the slide area. Locations of the test holes and <br />test pits were determined in the field by a representative of NWCC, Inc. and then surveyed by the client. The <br />elevations of the test holes were provided by the client after the instrument survey was completed. <br />The test holes were advanced through the existing fill materials, overburden soils and underlying bedrock <br />materials with 4-inch diameter continuous flight power augers using both track-mounted and truck-mounted <br />CME 55 drill rigs. The test pits were advanced with a trackhoe to better define the condition of the fill <br />materials and underlying natural soils. A representative of NWCC, Inc. logged the test holes and test pits. <br />Nine of the test holes were cased with slotted and solid 2-inch diameter PVC pipe so that groundwater levels <br />and soil movements could be monitored after the drilling was completed. <br />Samples of the subsurface materials were taken with either a 2-inch I.D. California liner sampler or a split <br />spoon sampler. The samplers were driven into the various strata with blows from a 140-pound hammer falling <br />30 inches. This test is similar to the standard penetration test described by ASTM Method D 153-86. <br />Penetration resistance values, when properly evaluated, indicate the relative density or consistency of the soils. <br />The depths at which the samples were taken and the penetration resistance values are shown on the logs of the <br />exploratory test holes in Figures #3 and #4. The logs of the test pits are shown in Figure #5. The Legend and <br />Notes associated with the logs are shown in Figures # 6 and #7, respectively. <br />• <br />Job Number: 08-8099 <br />NWCC, Inc. <br />Page 4