Berg, A, Durán, R, Rodríguez, F, Videla, JC, Jamett, N, Henríquez, JP, Morales, D & Bobadilla, A 2024, 'Lessons learned during initial slot blasting in Chuquicamata underground mine', in Daniel Johansson & Håkan Schunnesson (eds), MassMin 2024: Proceedings of the International Conference & Exhibition on Mass Mining, Luleå University of Technology, Luleå, pp. 787-807.
(https://papers.acg.uwa.edu.au/p/2435_E-09/)
Abstract: Undercut blasting is one of the most important events during the life of an underground caving mine. The main objective of this process is to induce the caving propagation by cutting the lower part of the rock mass. This process requires a free face available that provides the rock with room to expand when is blasted and is the starting point of the breakage and caving. This free face can be achieved by creating a boundary weakening space through the access drift in the undercut level by drilling and blasting where the space created will serve as volume reception from the undercut ring blasting. The Chuquicamata Underground Mine, one of the most important underground operations have implemented various drill & blasting designs during the life of the project to face the different conditions presented during the operation, always looking for the design optimization, increasing productivity and reducing costs. Part of the continuous improvement was to find the best strategy for the slot blasting for the new macro-blocks, South and North following the lessons learned from the initial slot blasting in the Central macro-blocks. This document compiles 4 years of information about slot blasting and shows the new strategy implemented which increased the development rate of the slot in the undercut level by opening the free face in multiple sectors reducing the cycle time and ramp-up time. All the lessons learned provide the information to face the initial slot blasting for the next 12 macroblocks planned for the first level.