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EXHIBIT GEOTECHNICAL STABILITY <br /> Von Doose Mine 110(1)Reclamation Permit Application <br /> Geotechnical Stability <br /> Slope Stability <br /> As described in Exhibit B, the natural slopes in the Lower Affected Area are steep and composed of a <br /> Cryothents-Rubble land complex typical of steep mountain slopes. The abundant cobbles and stones in the <br /> matrix are very angular and immature,typical of colluvium that stabilizes steep mountain slopes. The stable <br /> natural slopes in the affected area that will underly the proposed waste rock dump and laydown area ranges <br /> from 1.3:1 to 1.8:1 (h:v). <br /> The waste rock dump will be composed of blast rock that will exceed the size and angularity of the native <br /> slope material. The cap material will be comprised of the same native material that is demonstrated to be <br /> stable on the steeper native slope. <br /> Trautner Geotech, LLC (Trautner) conducted a site visit of the proposed waste rock dump and laydown <br /> area on July 16, 2019 and completed theoretical factor of safety(FS)calculations of the anticipated slopes <br /> of the proposed operations(see Attachment Zl.Trautner Geotech Slope Stability Overview). <br /> Trautner's calculations demonstrate that while the dump is active, a slope of 1.5:1 is sufficient in order to <br /> achieve the Division's FS standard of 1.3. Following completion of mining, the reclaimed slope will be <br /> regraded to 2:1, resulting in a FS of 1.55. These FS calculations are theoretical because the waste rock <br /> dump and laydown area do not yet exist for field/lab testing. However, the calculations used <br /> variables/assumptions that represent conditions anticipated during the proposed operation. <br /> Over the course of the operation as the waste rock dump is established, AMR will key-in and bench the <br /> waste rock dump material into the native slope in conformance with recommendations from Trautner. This <br /> extra step will add further stability to the slope that was not factored into the FS calculations. Additionally, <br /> AMR will periodically consult with Trautner and/or other geotechnical engineers over the course of the <br /> operation to ensure that the anticipated stability is being achieved throughout the permit area. <br /> AMR is proposing a final reclaimed grade of 2:1 for the waste rock dump because it achieves a FS of 1.55; <br /> it is the least steep slope that can be reasonably achieved with the underlying topography; and it minimizes <br /> disturbance to RMT's property. <br /> Similarly,the cut and side slopes of the laydown area are proposed at 2:1, with the same FS of 1.55. This <br /> slope is the least-steep grade in that location to allow for a functional near-flat laydown area that can support <br /> the operation. The composition of the side slopes will be derived from weathered bedrock and angular <br /> colluvium. The cap material of the side slopes will be identical to the cap material for the waste rock dump. <br /> With the limits of the proposed operation, it is not feasible to achieve a 3:1 grade in the affected area. The <br /> cross-section below demonstrates that to do so would require an enormous volume of fill material beginning <br /> from the top of the proposed waste rock dump to over 500 feet to the other side of the valley. This would <br /> Page 1 of 2 <br />