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Homestake 2011 Geotechnical Observations Pitch Reclamation Project Indian Creek and Tie Camp Creek Waste Rock Dumps bentonite. The wellhead was completed with concrete and 8 inch steel protective casing and concrete apron The new piezometers were developed in September by purging with a combination of 3- inch diameter by 36 -inch poly - bailers and a Grunfos 2 -inch Redi -Flow® impeller pump. Prior to, and between purging and pumping, piezometers were surged with a 1 -inch diameter by 24 -inch PVC slug and a 3 -inch by 24 -inch PVC Slug. The entire screen length of both piezometers was surged with slugs prior to purging. Wells were then bailed by hand until water cleared. Additional casing volumes were then removed with the impeller pump and field parameters were recorded in five minute intervals until parameters had stabilized. The total volume of water removed from 1010300R was approximately 100 gallons, or a total of 5 well casing volumes. A slug and bailer were used to extract approximately 25 gallons of turbid water. The well began to clear after 25 gallons and an impeller pump was used to produce approximately 75 gallons of water (or approximately 4.5 well casing volumes). The pumping rate during development of 1010300R was approximately one gallon per minute (gpm). The piezometer quickly recovered to static water level after development and is now measured monthly. The total volume of water removed from 1010370R was approximately 105 gallons, or a total of approximately 10 well casing volumes. A slug and bailer were used to extract approximately 25 gallons of turbid water. The well began to clear after 25 gallons and an impeller pump was used to produce the rest of the total volume. The pumping rate during development of 1010370R was approximately 1 gallon per minute (gpm). The piezometer quickly recovered to static water level after development and is now measured monthly. 2. Tie Camp Waste Rock Dump a) "10400 - 10100" Level Site Description: The Tie Camp Waste Rock Dump was regraded in 1994 following procedures approved in the February 1994 Technical Revision. During 1995, minor, localized areas of slope instability were noted, corrected, and reported in the 1995 Annual Geotechnical Report. 2011 Observations: Piezometer TC10375 monitors the Tie Camp Creek Waste Rock Dump. In 2011, water levels averaged 168.1 feet bgs, with a maximum observed seasonal fluctuation of 1.83 feet between May and June. The maximum fluctuation was down from the 2008 maximum fluctuation of 12.3 feet and 6.1 feet in 2009. This is deemed a normal and acceptable seasonal variation. Field observations indicate that the repairs performed in 1995 were successful and no new areas of surficial instability were observed from 1996 through 2011. In 2012, we will continue to monitor the surface conditions of the Tie Camp dump after the spring snow melt. 3. Piezometers — 2011 General Comments The 2011 water level measurements showed a maximum differential following snow melt in line with historical readings. Following the dry conditions of 2001 through 2003, the seasonal variations have increased in recent years as heavier snow packs have Homestake Pitch Reclamation Project 2011 Annual Geotechnical Report M- 1977 -004HR Page 4 December 19, 2011 2011 AnnualGeotechnicalReportText _Final.doc