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Homestake Pitch Reclamation Project <br />2008 Geotechnical Observations <br />Indian Creek and Tie Camp Creek Waste Rock Dumps <br />1. Indian Creek Waste Rock Dump <br />a) "10800" Level <br />Site Description: Identical to that of past reports for 1996 through 2007. <br />2008 Observations: The 2008 observations are similar to those reported for this area <br />during the past twelve years. Visual inspection of the area has revealed no evidence of <br />settling or slumping of.the rock dump material in 2008. Drainage channels are functioning <br />as designed. <br />b) "10780-10650" Level <br />Site Description: Identical to that of past reports for 1996 through 2007. <br />2008 Observations: The 2008 observations are similar to past observations. Visual <br />inspection of the area has revealed no evidence of settling or slumping of the dump <br />material in 2008. Drainage channels are functioning as designed. <br />c) "10650-10600" Level <br />Site Description: Identical to that of past reports for 1996 through 2007. <br />2008 Observations: Similar to the past twelve years, the water level measurements in <br />Piezometer IC10630 show a small rise in late-May during the snow-melt of a foot or less <br />and drops back to a normal range within a month. As noted in previous reports, in October <br />2001, an obstruction was removed from Piezometer IC10600, allowing it to be used once <br />again for the collection of piezometric surface data. In June of 2005 and again in 2007, a <br />level fluctuation of nine feet was observed in this piezometer, which was the greatest <br />fluctuation to date in water elevation since the obstruction was removed. In 2006, the <br />water level fluctuation was small at 1.5 feet. In 2008, the water level fluctuation rose by 7.7 <br />feet between late May and late June then dropped back to its a normal range by mid- <br />August. In 2008, the water level average in Piezometer IC10600 was 251.6 feet below <br />ground surface (bgs) and was consistent with the readings from previous years. This <br />condition is similar to other piezometers in the Indian Creek dump, and is deemed as an <br />acceptable seasonal variation. The water level increases in 2005, 2007 and 2008 were <br />likely a result of heavy snow pack and very wet spring conditions. <br />d) "10725-10525" Level <br />Site Description: Identical to that of past reports for 1996 through 2007. The minor overlap <br />between this level and other bench designations reflects the original bench configuration. <br />2008 Observations: Piezometers IC10600 and IC10525 bound this area. In 2008, the water <br />level in Piezometer IC 10525 increased by 7.8 feet in late May and June and, similar to <br />Piezometer IC10600, dropped back to normal levels in August. This behavior is very similar <br />to that of past reports for 1996 through 2007. In 2008, the average water level in IC10525 <br />was 227.2 feet bgs, in a total dump thickness of approximately 229 feet at this location.