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Homestake Pitch Reclamation Project 2014 Geotechnical Observations Indian and Tie Camp Rock Dumps 1. Indian Creek Waste Rock Dump a) "10800" Level Site Description: Identical to that of past reports for 1996 through 2013. 2014 Observations: The 2014 observations are similar to those reported for this area during the past sixteen years. Visual inspection of the area revealed no evidence of settling or slumping of the rock dump material in 2014 and the drainage channels are functioning as designed. The drainage on the west side of the upper part of the Indian Dump, just above the sericite stockpile, where the dump intersects native ground, had undergone minor erosion. In 2012, a low gradient diversion ditch, oriented roughly perpendicular to the main channel, was excavated allowing water from the channel to be diverted and dispersed at lower velocities. Boulders were placed above the steep section of the channel and rip -rap was placed below the boulders. The boulders and rip - rap function as energy dissipaters such that flow velocities are reduced and sediment retention is enhanced. Observations in 2014 indicate that this repair appears to have corrected the erosion issue. The area will be visually inspected after snow melt and heavy precipitation events. "10780 - 10650" Level Site Description: Identical to that of past reports for 1996 through 2013. 2014 Observations: The 2014 observations are similar to past observations. Visual inspection of the area revealed no evidence of settling or slumping of the dump material. The drainage channels are functioning as designed. b) "10650 - 10600" Level Site Description: Identical to that of past reports for 1996 through 2013 2014 Observations: In 2014 the water elevation in this piezometer rose by approximately 3.5 feet between January and May, and then fell back to its normal range by the end of June. In 2014 the water level in IC10630 increased in elevation by 7.7 feet between January and May. Between May and December the water level in IC10630 dropped 6.2 feet to elevation 10429.97. As previously mentioned, it appears that heavier than normal rainfall during the summer months prevented this piezometer from dropping completely to its January level. A higher than normal snowpack resulted in a greater spring rise in the phreatic surface. As noted in previous reports, in October 2001 an obstruction was removed from Piezometer IC10600, allowing it to be used for the collection of water level data. Between 2007 and 2011, the water level increased between 6.5 to 12.5 feet in May /June as a result of a very heavy snow melt. The water level then dropped back to its normal range by the end of summer. By comparison, in 2012 and 2013, the water level increased by 1.4 and 3.2 feet, respectively, and then fell back to its normal level by the end of summer. Homestake Pitch Reclamation Project Page 1 2014 Annual Geotechnical Report December 23, 2014 M- 1977 -004HR 2014AnnualGeotechnicalReportText _Final.doc