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Mr. Chri Oestreich <br /> September 29, 2023 <br /> Page 4 <br /> STABILITY ANALYSES RESULTS <br /> The stability analyses assumed the mining will be per the mine plan. The plan includes dry mining in the northwest cell <br /> as water levels will be controlled by the slung wall. The perimeter mine slopes will be no steeper than 3h:1 v. <br /> The factor of safety shown below is the minimum factor of safety of the conditions listed above. <br /> TABLE 1 -SLOPE STABILITY RESULTS AND SETBACKS <br /> Section Location Critical Structure Static Factor of Seismic Factor of DRMS Draft FOS <br /> Structure Setback From Safety at Safety at Structure Requirement <br /> Mine Limit ft Structure 0.091 horizontal Static/Seismic <br /> 1 North side of L.G. Everist 29 2.09 1.53 1.5/1.3 <br /> Northwest Cell 1 Conveyor <br /> CONCLUSIONS <br /> Stability analyses were performed on the most critical section along the conveyor. Based on the Factors of Safety listed <br /> in the table above,the mine will not be a hazard to the conveyor provided the structure and the mine slopes,follow the <br /> mine plan. <br /> LIMITATIONS <br /> Our review is based on regional geologic mapping, present mining plans,and in part borehole data by Civil Resources <br /> and Cesare, Inc. Civil Resources is not responsible for work by others. Stability analyses were performed using typical <br /> strength parameters for the various strata in the critical sections discussed above. Should the mining plans change or <br /> subsurface conditions vary from those portrayed in this letter,we should be contacted in order to re-evaluate the <br /> potential affects on permanent man-made structures. Stability analyses were run at the structure in question and were <br /> not run on failure surfaces closer to the highwall. Note also that surcharge loads due to temporary material stockpiles <br /> and overburden berms were not considered in the analysis. <br /> Please call with any questions or comments. <br /> Sincerely, <br /> Civil Resources, LLC <br /> 1 <br /> Gary Linden, P.G. <br /> Senior Engineering Geologist <br /> Attachments: Galena Model Cross Sections and Outputs: Section 1 <br /> REFERENCES <br /> Colton, R.B., 1978,"Geologic Map of the Boulder-Fort Collins-Greeley Area, Colorado", U.S.G.S. Map 1-855-G. <br /> J-\Bestway-213\Inouye\DRMS\Exhibits\Stability Analysis\LG Evenst conveyor\Stability analysis LG Everist-Inouye.doc <br />