106 • Reduced dependence on active containment structures • Strong alignment with modern risk management frameworks These attributes position In-Pit TSFs as a robust and technically defensible alternative for tailings management in open-pit mining operations. 5. METHODOLOGICAL APPROACH AND ENGINEERING DECISIONMAKING 5.1 Methodological Framework for In-Pit TSF Evaluation The evaluation of In-Pit Tailings Storage Facilities (In-Pit TSFs) requires an integrated methodological approach that combines geotechnical, hydrogeological, hydraulic, operational, and risk-based analyses. Unlike conventional surface TSFs, where dam design dominates decision-making, In-Pit TSFs shift the focus toward system behavior, long-term containment performance, and life-of-mine integration. The methodological framework applied in this study follows four sequential stages: 1. Site screening and feasibility assessment 2. Engineering characterization and numerical analysis 3. Risk-informed performance evaluation 4. Multi-criteria decision-making and optimization This approach is aligned with international best practice and consistent with the Global Industry Standard on Tailings Management (GISTM) principles (ICMM, UNEP & PRI, 2020). 5.2 Site Screening and Feasibility Criteria Initial screening determines whether an exhausted open pit is suitable for use as an In-Pit TSF. Key exclusion and suitability criteria include: • Adequate pit geometry and residual storage capacity • Competent rock mass conditions and acceptable slope stability • Favorable hydrogeological gradients allowing inward seepage • Compatibility with mine sequencing and production schedules Table 3 summarizes the primary screening criteria applied during the prefeasibility stage. Table 3. Key site screening criteria for In-Pit TSF feasibility Criterion Evaluation focus Pit geometry Depth, volume, slope angles Rock mass quality RMR / GSI, structural fabric Hydrogeology Groundwater gradients, permeability Seismicity Regional seismic hazard Mine planning Alignment with life-of-mine
RkJQdWJsaXNoZXIy MTM0Mzk2