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Mr. Chris Oestreich <br /> June 29, 2023 <br /> Page 5 <br /> TABLE 1 -SLOPE STABILITY RESULTS AND SETBACKS <br /> Section Location Critical Structure Static Factor Seismic Factor of DRMS Draft FOS <br /> Structure Setback From of Safety at Safety at Structure Requirement <br /> Mine Limit(ft) Structure (0.132g Static/Seismic <br /> horizontal) <br /> 1 Southeast Westgate 55 1.5 1.2 1.5/1.2 <br /> Corner Road <br /> 2 Northeast Relocated 95 1.6 1.2 1.5/1.2 <br /> Corner McKay Ditch <br /> CONCLUSIONS <br /> The Westgate Road and the relocated McKay Ditch are the nearest structures to the mine and are stable based on the <br /> Factors of Safety listed in the table above. All other structures in the area are located at or at greater than those <br /> described above. Factors of Safety on other neighboring structures will be greater than those summarized in the Table <br /> above. <br /> LIMITATIONS <br /> Our review is based on regional geologic mapping, present mining plans, laboratory and borehole data. Stability <br /> analyses were performed using typical strength parameters for the various strata in the critical sections. Should the <br /> mining plans change or subsurface conditions vary from those portrayed in this letter,we should be contacted in order to <br /> re-evaluate the potential affects on permanent man-made structures. Stability analyses were run at the structure in <br /> question and were not on failure surfaces closer to the mine limit. <br /> Please call with any questions or comments. <br /> Sincerely, <br /> Civil Resources, LLC <br /> Gary Linden, P.G. <br /> Senior Engineering Geologist <br /> Attachments: <br /> Figures 1 and 2 <br /> Attachment A Geotechnical Laboratory Data <br /> Attachment B Galena Stability Model Outputs and U.S.G.S. Uniform Hazard Tool <br /> REFERENCES <br /> Trimble, D.E. and Machette, M.N., 1979, "Geologic Map of the Greater Denver Area, Front Range Urban Corridor", <br /> U.S.G.S. Map I-856-H. <br /> J:1Bestway-2131church-mckaylgeotechlStability\Report\Stability analysis-Church Mckay Change of Operator.doc <br />