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Cripple Creek & Victor Gold Mine <br />Valley Leach Facility Expansions <br />Detailed Design for Permitting <br />NewFields Project No. 475.0106.064 <br />September 2025 <br /> <br /> <br /> <br />Page 22 <br />5.2.1. Model Development <br />Potential settlement was evaluated for critical sections beneath the VLF Expansion that include <br />portions of the facility that will be expanded over VLF2, the VLF1 slopes surrounding the PSSA, <br />and the portion of the facility constructed over the backfilled Elkton Pit. The sections evaluated <br />are shown on Figure 1 in Appendix E. <br />Three VLF Expansion sections were selected for settlement evaluation. Section A presents an area <br />of substantial ore stacking on top of fill materials. This section represents the area of largest <br />differential settlement and strain. Section D presents an area of substantial pit backfill and ore <br />stacking over top of the full pit profile. The PSSA section presents a typical cross section of the <br />double lined pond and was selected for evaluation to ensure the PSSA volume is not reduced by <br />settlement. <br />RS2 uses an advanced meshing algorithm to generate a base mesh for the model. The mesh <br />density for the presented models was further refined and increased in locations where stress <br />concentrations were expected. The model used grid element sizes ranging from as large as 60 <br />feet in areas outside of the Elkton Pit, to less than 1 foot in locations of stress concentrations <br />such as the abrupt transitions from intact bedrock to backfill near the Elkton Pit walls. Variations <br />in grid size were investigated, and the final grids utilized in the presented models were found to <br />be sufficiently dense to develop accurate estimates of long-term settlement. <br />5.2.2. Material Properties <br />Material properties used in the settlement evaluation were developed in the VLF2 Phase 3 design <br />(NewFields, 2020) and are summarized in Table 5.3 and further discussed below. <br />Table 5.3 – Material Properties <br />Material Compactive <br />Effort <br />Unit <br />Weight <br />(pcf) <br />Poisson <br />Ratio <br />Subgrade Modulus <br />Isotropic Tangent Modulus <br />(ksf) m a <br />Ore (Existing and Proposed) N/A 120 0.2 700 N/A N/A <br />Pit Backfill and Fill <br />High 130 0.4 N/A 225 0.5 <br />Low 120 0.3 N/A 150 0.5 <br />Foundation (Sand and Gravels) Low 125 0.4 N/A 225 0.5 <br />Foundation (Bedrock) N/A 150 0.4 1e+6 n/a n/a <br />