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A structure agreement was sent to the owner of the Broad Ax Ditch, Richard M. Frazier, on August <br /> 30, 2022. The agreement was signed and returned on August 31, 2022 and is attached to this <br /> letter. Exhibit S and Map C-1 of the amendment application have also been revised to include the <br /> updated structure owner of the Broad Ax Ditch. <br /> 6.5 Geotechnical Stability Exhibit <br /> DRMS is reviewing the geotechnical analysis and our comments will be forthcoming. <br /> These comments were received in an adequacy letter on September 2, 2022. Responses are <br /> provided below. <br /> 2. Geotechnical Adequacy Review <br /> The Division of Reclamation, Mining and Safety(Division/DRMS) staff reviewed the <br /> geotechnical stability exhibit included with the Delta Paving Gravel Pit 112c permit amendment <br /> application (AM1), File No. M-1998-105. The following list describes the information used by the <br /> Division as presented in the permit amendment application to evaluate slope stability for the <br /> site. Please review the list and confirm the list is accurate. <br /> See the revised Geotechnical Stability Exhibit, including a full Bishop's Method of Slices analysis in <br /> GALENA. <br /> 1) The Factor of Safety calculation provided by the Applicant is not sufficient to elevate the <br /> slope stability for the amendment application. Please perform stability analysis models on <br /> the critical slope configurations during the mining and reclamation for the site. <br /> See the revised Geotechnical Stability Exhibit, including a full Bishop's Method of Slices analysis in <br /> GALENA. <br /> 2) The required stability analysis models must include surcharge loads from structures, roads <br /> topsoil and overburden stockpiles/berms and any other appropriate loads. <br /> See the revised Geotechnical Stability Exhibit, including a full Bishop's Method of Slices analysis in <br /> GALENA. A distributed load representing the nearby berm has been incorporated. <br /> 3) The Applicant states in the Mining Plan, the perimeter slopes will be mined at a 2H:1 V <br /> grade, the mining highwall will be mined at a near vertical slope to the halfway point of the <br /> final mining slope and the upper highwall will be knocked down to the final mining slope with <br /> a dozer after mining is complete in the area. <br /> Detail 1 on the Exhibit C-3 indicates the mining slope will be mined at a 2H.1 V slope from <br /> the ground surface to the final depth of the excavation. Please explain this discrepancy and <br /> revise the Mining Plan and/or Exhibit C-3 accordingly. The Division recommends all <br /> perimeter slopes are mined to the final reclamation slope of 3H:1 V. <br /> Exhibit C-3 has been revised to clarify the slope types: a Full Mining slope, a Final Reclamation <br /> slope, and an Active Highwall slope. See the revised Geotechnical Stability Exhibit, including a full <br /> Bishop's Method of Slices analysis in GALENA. <br /> Delta Paving <br /> September 2022 6 Lewicki&Associates <br />