A new approach to mining method selection based on modifying the Nicholas technique

The main purpose of this paper is to represent a solution to the problem of mining method selection (MMS) in mining projects. To this aim, the well-known MMS technique of Nicholas has been modified so that in addition to eliminate its defects, it would be possible for mining engineers to easily assign their engineering judgments to unsteady and uncertain characteristics of mineral resources. So, in order to resolve the problems of weighting of the Nicholas technique, analytic hierarchy process (AHP) as the most similar multi-criteria decision making (MCDM) tool to Nicholas technique was applied. Due to inability of crisp numbers for assigning of decision maker (DM) judgments to ambiguities of mineral resources, trapezoidal fuzzy numbers also were used for better modeling of those ambiguities. Moreover, a two-step algorithm containing hierarchical technical-operational model (HTOM) and also hierarchical economical model (HEM), inspired by Nicholas technique, was proposed. These models include some new criteria which are added to the Nicholas technique. Therefore using fuzzy AHP (FAHP), mining alternatives are firstly ranked based on HTOM and then, the most profitable of those alternatives is selected by the HEM. As a case study, the north anomaly of Choghart iron mine was used to compare the proposed approach with the Nicholas technique. The results indicated that the proposed approach eliminated the problems of Nicholas technique. Proposed approach also introduces a profitable mining alternative to start the mining operations. It should be applied to avoid further feasibility studies in mining projects. (C) 2009 Elsevier B. V. All rights reserved.