Assessment of mine post-closure strategies by integrating evidential reasoning and fuzzy cognitive maps: Toward sustainable mining policy

This study proposes a novel framework based on evidential reasoning and fuzzy cognitive map to evaluate post-closure strategies for open-pit mine reclamation, with a focus on sustainable mining. The framework enables a reasonable assessment of multiple strategies and criteria within a complex dynamic decision analysis system under uncertainty. This study introduces two novel aspects: linking the weight outputs of fuzzy cognitive maps to the evidential reasoning process and considering a broad range of criteria and reclamation strategies toward sustainable mining. This study considers various strategies, focusing on tailings, waste rocks, and demolition materials as filling materials to reclaim pits and reduce mine waste footprints. In evidential reasoning, causal weights were determined by a fuzzy cognitive map, which revealed that social criteria with a causal weight >0.96 were found the highest impact on cause-and-effect. The framework was applied to a large-scale mine with high discontinuities and acidity potentials, a local ecosystem with a high piezometric level, and low rainfall. A post-closure strategy using tailings as the main filling material was found most suitable, as it eliminates material transport and supply costs and reduces the adverse environmental effects and social complaints.