A new model of geo-environmental impact assessment of mining: a multiple-criteria assessment method integrating Fuzzy-AHP with fuzzy synthetic ranking

A new evaluation model for geo-environmental impact assessment of mining (GEIAM) is proposed. The evaluation framework in this model considers three groups of criteria, namely, geo-hazards risks, environmental risks, and resource damages. Fuzzy-analytic hierarchy process (AHP) was used to establish a multiple-criteria evaluation system and simultaneously command weighting to avoid vagueness and ambiguity in expert judgment. Membership function was employed to deal with the vagueness boundary problem of indices scoring and to help complete the ultimate fuzzy synthetic ranking. The model expresses the evaluation results with an integrated objective ranking and three criteria ranking. It was tentatively applied to assess an opencast limestone mine. The results indicated that the indices sequences were consistent with the mine background and the expert professional experience and better revealed the impact of geo-hazards risks. Specific assessment factors such as geo-hazards potential, engineering geological condition, and hydrogeological condition were prioritized for further improvement. Compared with existing GEIAM evaluation methods, the proposed assessment model focuses more on expert experience and judgment, breaks through the limitation of local estimation to variable attributes and, most importantly, satisfies the multi-purpose requirements to incorporate real considerations together for mining safety, geo-environmental protection, and natural resource conservation.