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Homestake Mining Company May 10,2019 <br /> Regular(112d)Operation Reclamation Permit Application Package <br /> 3.4.3.3.1 North Pit <br /> The North Pit contains the majority of monitoring points at the site (68 of 92). For the 2018 <br /> monitoring cycle, only two monitoring points in the North Pit had displacement values greater than <br /> their associated potential survey error. Drawing 7 shows the annual rate of movement in the North <br /> Pit from 2012 to 2018. Throughout the years, movement remains at a scale comparable to the <br /> associated potential survey error, with no movement recorded above 0.5 ft in a year nor below <br /> 0.4 ft for 2018. Drawing 10 shows the cumulative movement in the North Pit from 2012 to 2018 <br /> does not exceed 1.5 ft for any monitoring points. The general movement from monitoring points <br /> in the North Pit, therefore, indicates overall slope creep (BGC, 2019b). <br /> 3.4.3.3.2 South Pit <br /> The South Pit contains all monitoring points with significant amounts of movement. Over half of <br /> the monitoring points in the South Pit (15 out of 24) have displacement values greater than their <br /> associated potential survey error. Drawing 6 shows the annual rate of movement in the South Pit <br /> from 2012 to 2018. Throughout the years, movement occurs for several of the monitoring points <br /> on the order of a foot to several feet with as much as 9.5 ft in one year. However, 2018 only <br /> showed a maximum movement around 0.4 ft for any monitoring points. Drawing 9 shows the <br /> cumulative movement in the South Pit from 2012 to 2018 for several monitoring points with a <br /> range of 6 ft to 21 ft of total movement. The general movement from the monitoring points in the <br /> South Pit, therefore, indicates a discrete landslide failure with active failure (BGC, 2019b). <br /> Photo Stations <br /> As reported by EAI (2014), the program which operated for 13 years (2000 to 2013) found no <br /> appreciable change in the appearance of tension cracks and scarps except for"minor sloughing". <br /> The location and timing of the observed sloughing events were not provided. <br /> 3.4.3.4. Other Observations <br /> Other observations of slope failure include "sluff' on the East Wall of the North Pit at the <br /> 10,800 level in May 2015. The disturbed area measures approximately 40 ft wide, and it occurred <br /> on steep terrane of the East Wall near the head of the 1983 Northeast failure (Figure 3-15). <br /> EXHIBIT E-RULE 6.4.5(AMENDED RECLAMATION PLAN) Page 55 <br /> HOMESTAKE MINING COMPANY <br />