Optimising Mining Methods: A Case Study on Value Engineering and Trade-off Analysis

At Mining Plus (MP), we pride ourselves on delivering innovative solutions that optimise mining methods and enhance material handling systems. Recently, we were engaged to perform a comprehensive value engineering and trade-off analysis for a mining zone, with the primary objective of optimising mining methods and material handling options. This study focused on evaluating the potential benefits of Sublevel Open Stoping(SLOS) and Sublevel Caving (SLC) mining methods, while also assessing various material handling solutions, including traditional trucking, conveyors, shaft haulage, and the emerging Railveyor system. 

Challenges in Optimising Mining Methods 

The project posed several unique challenges, starting with the critical task of selecting the most suitable mining method and material handling system. The goal was to maximise Net Present Value (NPV) while ensuring cost efficiency and operational practicality. Each mining method, whether SLOS or SLC, came with its own set of advantages and limitations, particularly when considering throughput potential, capital and operational expenditures, and cash flow considerations. 

In addition to the complexity of selecting the ideal mining method, handling uranium in an underground environment added layers of complexity. Special ventilation strategies were needed to mitigate health and safety risks, particularly related to the exposure to radioactive materials. Moreover, the material handling trade-off analysis had to balance the tried-and-true traditional trucking systems with more innovative solutions, such as Railveyor, a technology that offers promising advantages in underground mining. 

Mining Plus’s Approach: Problem Solving and Solutions 

Mining Plus approached this complex challenge with a rigorous and systematic method, performing a detailed financial and technical trade-off analysis. Our evaluation compared the SLOS and SLC mining methods, alongside four material-handling options: traditional trucking, conveyor, shaft haulage, and the innovative Railveyor system. The analysis was underpinned by financial metrics, such as discounted NPV and cash flow, to ensure that we provided the most economically viable solution. 

The findings indicated that the optimal combination for maximising NPV was the use of SLC in conjunction with the Railveyor system at the -425 and -675 levels. The Railveyor, renowned for its efficiency in ore transport, offers a sustainable and cost-effective solution, particularly when combined with SLC's higher throughput capabilities. In addition to the technical recommendations, MP also provided a high-level ventilation review, proposing a forced ventilation system for sublevel caving operations to manage uranium exposure and protect worker safety. 

To ensure the long-term viability of this approach, MP recommended further geotechnical assessments to validate the feasibility of SLC in the specific mining zone and additional cost checks on Railveyor inputs to confirm its cost-effectiveness over time. 

The Outcome: Optimised Path Forward 

The trade-off analysis concluded that the SLC method, when paired with the Railveyor system, yielded the highest NPV and should be the preferred approach for the mining zone. This combination promises improved ore transport efficiency and reduced operational costs, providing a clear and economically beneficial path forward. 

However, to account for potential discrepancies in Railveyor cost projections, MP suggested that alternative material handling options, such as conveyor systems, be considered if Railveyors' cost exceeds expectations. The study also emphasised the importance of ongoing value engineering projects, including enhanced geotechnical work and ventilation planning, to address the unique challenges associated with uranium exposure. 

Ultimately, this project provided our client with a clear, optimised mining strategy that balances operational efficiency, cost-effectiveness, and safety. By selecting the right combination of mining methods and material-handling systems, our client can move forward with confidence, maximising both economic returns and sustainable mining practices. 

At Mining Plus, we’re committed to optimising mining methods and material handling strategies to help our clients achieve maximum value. Through careful analysis, innovative problem-solving, and the application of cutting-edge technologies, we deliver insights and recommendations that ensure success in the complex and ever-evolving mining industry.