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Hom( :stake 2009 Geotechnical Observations Pitch Reclamation Project Indian Creek and Tie Camp Creek Waste Rock Dumps IC 10525 was 227.2 feet bgs, in a total dump thickness of approximately 229 feet at this location. e) "10600-10400" Level Si Description Identical to that of past reports for 1996 through 2008. 2009 Observations Piezometer IC10440 was located in this area; however, it was lost in September 1996. Piezometer IC10525 can also be considered to be within the area. The 2009 data for that piezometer is described in the previous section. f) "10400 - 10370" Level Si Description Identical to that of past reports for 1996 through 2008. 2009 Observations The 2009 field observations are similar to those reported in past reports. Piezometer I.C10360 is located in this area. Water levels in this piezometer averaged about 224.3 feet bgs, with a seasonal fluctuation of approximately 8.8 feet. Despite a record snow pack in 2008 and heavy snow pack again in 2009, as was noted in 2008, the reading in IC10360 represent the smallest rise in the piezometrc surface data since 2002. The total depth of this piezometer is 260 feet and the thickness of the dump is approximately 240 feet. During the winter of 2007, wildlife knocked off the casing of piezometer IC10370 and kicked debris into the 2 inch pipe. This piezometer had never shown seasonal water levels fluctuations greater than one foot, with the averaged water level of 190.7 feet bgs. The bottom of this piezometer is 192 feet bgs. In 2009, we were able to flush out this piezometer with pressurized water to within three feet of its historical depth of 192 feet bgs. Now the total depth is approximately 189 feet bgs, with no water in the pipe. The flushing will allow use of piezometer 10370 as part of the Indian Creek monitoring program. During 1997, Homestake reconstructed the face of the permanent low -grade stockpile located on the Indian Creek Waste Rock Dump. The purpose of the slope reconstruction was to reduce the potential for infiltration and promote more rapid runoff from the slope. No seepage was observed in this area in 2009. g) "10300 - 10100" Level Si Description The Indian Creek Waste Rock Dump was regraded in 1994 following procedures approved in the February 1994 Technical Revision. During 1995, several minor, localized areas of slope instability were noted, corrected, and reported in the 1995 Annual Geotechnical Report. 20 Observations Field observations indicate that the repairs performed in 1995 were successful and no new areas of surficial instability (slips) were observed from 1996 through 2009. Piezometer IC10300 is located in-this area. Field records indicate that the 10300 piezometer was originally drilled to a total depth of 210 ft. The final depth of the installation was not recorded in the field record at that time. Inspection of IC10300 in 2008 indicated that the bottom of the standpipe had become filled with silt to a depth of about 180 ft. bgs, as, indicated by sounding the total depth of the standpipe. A steel surge block was lowered into the standpipe, and rather than encountering a blockage, the surge block became partially submerged in the slurry-like material, which covered the steel surge block as when it was returned to the surface. It was conclude that the water levels recorded over the past Homestake Pitch Reclamation Project Page 2 2009 Annual Geotechnical Report December 15, 2009 M- 1977 -004HR 2009AnnualGeotechnicalReportText _Final.doc