Mud inflow risk assessment in block caving operation based on AHP comprehensive method

Abstract

Increasing the depth of mining operations becomes fundamental due to the depletion of the shallower high-grade orebodies. Besides, technological developments make deep mining operations feasible. Block and panel caving are classified into large-scale production methods applicable to deep low-grade massive deposits. When mining goes deeper, evaluating the rock mass behavior and conditions for caving becomes more complicated during mine planning and design. The limited and poor quality data, unexpected changes in conditions as well as natural variability are the source of all risks in cave mining. Mud inflow is a phenomenon that can plague caving operation with many obstacles such as fatalities, damage, dilution, production delay, or mine closure. In this research, a safety risk assessment framework is presented based on analytic hierarchy process (AHP). Thus, an extensive statistical analysis of all effective parameters in mud inflow was performed at one of the main operation sectors of el Teniente copper mine, Codelco, Chile. The statistical results were used to ranking risk effective parameters in AHP method. The results of this study introduce a robust method for prioritization of safety risk in block caving projects.