2019-06-28_REVISION - M1977004 (9)

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Homestake Mining Company May 10,2019 Regular(112d)Operation Reclamation Permit Application Package 2016/2017 annual monitoring cycle movement, with almost no incremental movement in the 70.5 ft bgs zone (i.e., 0.01 inches of incremental movement between the 2016/2017 and 2017/2018 annual monitoring periods). The incremental movement for 46.5 ft bgs zone has remained approximately the same for the past two years, at 0.06 inches. Ground movement trends within 198-1 indicate slope creep is the primary form of ground movement (BGC, 2019a). Inclinometer data for 198-2 indicates two zones of movement at 17.0 ft and 212.0 ft bgs. The incremental movement for both zones has shown a significant decrease from previous 2017 annual monitoring cycle movement. Specifically, there is no real incremental movement at 212.0 ft and only 0.01 inches of incremental movement at 17.0 ft. Ground movement trends within 198-2 indicate a lower propensity for discrete shear plane movement than inclinometer 198-1. Movement within the shallowest ground movement zone is in an uphill orientation contrary to the anticipated direction of movement. This could suggest a possible error or fluctuation at a casing joint (BGC, 2019a). Inclinometer readings taken in 2018 for 198-1 and 198-2 indicate movement along zones observed in previous years has decreased in the 2018 annual monitoring cycle but is in line with what has been seen in recent years, suggesting a deceleration of slope movement (Figure 3-17 through Figure 3-18)) (BGC, 2019a). Inclinometer readings taken in 2018 for 198-3, IN-1, IN-2 and IN-3 did not indicate real movement (i.e., zones of measured incremental movement did not exceed the estimated error range)for the 2018 inclinometer monitoring cycle. (Figure 3-19 through Figure 3-22)) (BGC, 2019a). CNI (1982) provides inclinometer survey data for inclinometers 1-2 and 1-3 for surveys performed on September 14, 1981 and November 17, 1981. In Inclinometer I-3 (located near the middle of the slope, see Drawing 01) CNI (1982) interpreted a shear at a depth of approximately 270 ft below ground surface. Inclinometer 1-2 (located in the upper half of the slope, see Drawing 01) was not sheared but shows displacement which CNI (1982) interprets as an indication that the failure plane is deeper than 280 ft at that location. Inclinometer#1 is not mentioned by CNI (1995). Inclinometer surveys for 194-1, 194-2, and 194-3 were not available for this assessment. EXHIBIT E-RULE 6.4.5(AMENDED RECLAMATION PLAN) Page 47 HOMESTAKE MINING COMPANY