a new classification system for evaluation and prediction of unplanned dilution in cut-and-fill stoping method

Production planning in mineral exploitation should be undertaken to maximize exploited ore at a minimum unplanned dilution. unplanned dilution reduction is among the ways to enhance the quality of products, and hence, reduce the associated costs, resulting in a higher profit. in this way, firstly, all the parameters contributing to unplanned dilution in underground stopes and specifically the cut-and-fill stoping method are identified. secondly, the parameters are weighed using the fuzzy-delphi analytical hierarchy process. thirdly, the most effective parameters are selected among the pool of effective parameters. finally, in order to present a novel classification system for an unplanned dilution assessment, a new index called stope unplanned dilution index (sudi) is introduced. sudi represents the extent to which a cut-and-fill stope is susceptible to unplanned dilution. that is, having the value of this index, one may classify the cut-and-fill stopes into five groups according to robustness versus unplanned dilution: very strong, strong, moderate, weak, and very weak. sudi is applied to10 stopes in different parts of venarch manganese mines (qom, iran). in this way, a semi-automatic cavity monitoring system is implemented in the stopes. the regression analysis method shows that there is a relationship between sudi and the actual unplanned dilution in equivalent linear overbreak/slough with a correlation coefficient (r² = 0.8957).