Determining the impact of haulage optimisation software on addressing open pit mining economic and environmental challenges: a case study

Abstract

This study assessed whether optimised surface mining schedules reduce environmental impact, thereby improving ESG-related factors. The study employs both qualitative and quantitative methods. A literature review revealed much research on optimisation and carbon footprint, but few studies on incorporating carbon footprint into strategic mine planning. The quantitative approach entailed the collection of secondary data for running an optimisation on a mine planning software. Hexagon’s MinePlan Optimiser was used to run the optimisation. Two key variables were analysed by contrasting and comparing the baseline and optimised models generated. These variables include Net Present Value (NPV), which helps determine the financial feasibility of the mining models and their carbon emissions. This, in turn, allows us to calculate the carbon footprint and assess the environmental impact. To derive meaning from the data, three main methods of analysis were employed: linear regression, Spearman’s correlation, and a P-value hypothesis test. The study achieved its initial objective by showing that there is a benefit in running an optimised model for mine planning purposes at Mine A. Results show that at Mine A’s projected NPV will always be 62% higher than when running a baseline model. Furthermore, the NPV from the baseline model portrayed a high rate of decay at 0.667 versus 0.118 from the optimised model. This indicates the baseline model’s sensitivity to long-term project timelines and fluctuating markets. The optimised method presents an opportunity to manage emissions during the high operational costs phases, which is represented by a 31% improvement in carbon emissions during the periods of high operational costs, whilst maintaining a positive NPV when compared with the baseline model. Therefore, the optimised model presents a better chance of achieving financial feasibility and balancing environmental impact, thereby ensuring that Mine A can align with the environmental aspect of ESG through lowering the carbon footprint resulting from its hauling operations.