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Homestake 2014 Geotechnical Observations Pitch Reclamation Project Indian and Tie Camp Waste Rock Dumps 2014 when the water level in IC10370R increased in elevation by 11.4 feet between January and June. This condition is similar to other piezometers in the Indian Rock Dump, and reflects the relatively high seasonal snow pack in the area. Between June and November the water level in IC10370R dropped 3.1 feet to elevation 10182.4 feet amsl. Similar to IC10630, it appears that heavier than normal rainfall during the summer months prevented this piezometer from dropping completely to its January level. Piezometer IC10360 is also located in this area. Water levels in this piezometer rose by 6.9 feet this past spring compared with 5.6 feet in 2012 and 11.1 feet in 2011. The average depth to water in 2013 was 223.0 feet bgs compared with 227.8 feet bgs in 2012, reflecting a gain in the average water level of 1.3 feet for the two year period. In 2014 the water level in IC10360 increased 7.7 feet between March and June. This condition is similar to other piezometers in the Indian Rock Dump, and reflects the relatively high seasonal snow pack in the area. Between June and December the water level in IC10360 dropped 6.5 feet to elevation 10147.72 feet amsl. Unlike other Indian Rock Dump piezometers, the water level in IC10360 dropped below the January reading in February and March. "10300 — 10100" Level Site Description: The Indian Rock Dump was re- graded 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. 2014 Observations: Field observations indicate that the repairs performed in 1995 were successful and no new areas of surficial instability were observed from 1996 through 2014. Due to problems in Piezometer IC10300 over several years with sediment buildup in the casing, in 2011 it was abandoned and replaced by Piezometer IC1030OR located approximately 30 feet to the west of IC10300. The piezometer was terminated at a depth of 210 feet and completed with 20 feet of screen and an 8 -inch steel well protective casing set in concrete. A transducer was also placed in the Piezometer IC1030OR in late 2011 to assist in monitoring water levels. In 2014, the water level in Piezometer IC1030OR rose by 17.9 feet compared with 11.1 feet in 2013 and 0.2 feet in 2012. The average depth to water for the past two year period increased by 2.0 feet, reflecting an increased snow back and heavier summer precipitation in the area in 2014. However, the water levels dropped back to normal levels after the spring snow melt. Homestake Pitch Reclamation Project Page 3 2014 Annual Geotechnical Report December 23, 2014 M- 1977 -004HR 2014AnnualGeotechnicalReportText _Final.doc