Optimizing Overall Slope Angle and Net Present Value (NPV) Through the Utilization of Ground-Based Pit Wall Monitoring Data

Abstract

In open-pit mining, determining the optimal Overall Slope Angle (OSA) is a complex but essential task that balances safety and economic considerations. Slope angle decisions directly impact both the stability of open pit mine walls and the economic viability of the operation. This research proposes a structured approach to OSA optimization by leveraging real-time ground-based pit-wall monitoring data. By integrating radar system data with detailed geotechnical models, the study assessed slope stability in a data-driven manner. Through the use of Rocscience Slide3 software, stability analysis was conducted on actual mine data, offering an understanding of the effectiveness of using monitoring technologies to guide slope design adjustments. A significant finding of this study was the regressive trend observed in the radar data obtained from the chosen mine for this study, which indicated that steepening the slope could be feasible without compromising safety. The initial and modified slopes were evaluated by calculating the Factor of Safety (FS), a key metric for assessing stability. The FS was observed to In open-pit mining, determining the optimal Overall Slope Angle (OSA) is a complex but essential task that balances safety and economic considerations. Slope angle decisions directly impact both the stability of open pit mine walls and the economic viability of the operation. This research proposes a structured approach to OSA optimization by leveraging real-time ground-based pit-wall monitoring data. By integrating radar system data with detailed geotechnical models, the study assessed slope stability in a data-driven manner. Through the use of Rocscience Slide3 software, stability analysis was conducted on actual mine data, offering an understanding of the effectiveness of using monitoring technologies to guide slope design adjustments. A significant finding of this study was the regressive trend observed in the radar data obtained from the chosen mine for this study, which indicated that steepening the slope could be feasible without compromising safety. The initial and modified slopes were evaluated by calculating the Factor of Safety (FS), a key metric for assessing stability. The FS was observed to decrease from 1.59 to 1.401 after the slope adjustment, remaining within industry and company-accepted safety thresholds. This calculated reduction demonstrated that, even with a steeper slope, the mine retained a satisfactory safety level, thus validating the reliability of using ground-based radar data to inform slope modifications. In addition to confirming slope stability, the study assessed the economic implications of slope adjustments using MinePlan 3D software. An economic analysis revealed that increasing the OSA by just 1° yielded a 1.534% improvement in the mine's Net Present Value (NPV). This finding underscored the economic advantages of refining slope angles in real-time based on accurate monitoring data. Overall, this paper illustrates how real-time monitoring, paired with geotechnical modeling and economic assessment, can effectively optimize slope design. This approach not only reduces the likelihood of slope failures but also enhances profitability and extends the operational life of mine, providing a solid foundation for balancing safety and economic goals in open-pit miningdecrease from 1.59 to 1.401 after the slope adjustment, remaining within industry and company-accepted safety thresholds. This calculated reduction demonstrated that, even with a steeper slope, the mine retained a satisfactory safety level, thus validating the reliability of using ground-based radar data to inform slope modifications. In addition to confirming slope stability, the study assessed the economic implications of slope adjustments using MinePlan 3D software. An economic analysis revealed that increasing the OSA by just 1° yielded a 1.534% improvement in the mine's Net Present Value (NPV). This finding underscored the economic advantages of refining slope angles in real-time based on accurate monitoring data. Overall, this paper illustrates how real-time monitoring, paired with geotechnical modeling and economic assessment, can effectively optimize slope design. This approach not only reduces the likelihood of slope failures but also enhances profitability and extends the operational life of mine, providing a solid foundation for balancing safety and economic goals in open-pit mining.