Mining Mirror May 2018 - Page 22

Mining in focus A drill rig in action at De Beers’ Venetia diamond mine in the Limpopo province of South Africa. especially those with already large patterns, will need this subdrill to be loaded. From my experience, unless a geologic feature is already present that eliminates the need for a subdrill, the subdrill has to be there and no device can be put in the bottom of the hole to stop this requirement. Improper elimination of the subdrill will lead to: • Poor floors with toes; and • Possible secondary blasting to treat floor conditions, reduced haulage times as trucks need to go slower over these bumps, and increased maintenance on equipment driving over these areas. Understanding of blasting is critical Drilling and blasting is an extremely complicated process that relies heavily on proper understanding of design, [20] MINING MIRROR MAY 2018 loading procedures, geology, and safety. While many drill and blast teams seek to optimise their results, they can often be pushed to reduce drill and blast costs at a mine. The normal operating procedures that are seen all over the world have been mentioned above, but have severe ramifications to all other downstream processes. If you do not work in drill and blast but are involved in any other operation at a mine, a basic understanding of drilling and blasting is critical to ensure that your process is not negatively affected and your performance diminished. If you are on the drill and blast team, you must either convince your management that a mine-to-mill optimisation approach is best, or look for cost reduction opportunities that do not impact the other mine processes. b About the author Anthony Konya is a senior engineer and consultant with Precision Blasting Services; the co-founder and instructor at AcademyBlasting.com; and an instructor at the Missouri University of Science and Technology. Anthony works worldwide for mining and construction operations on drill and blast optimisation programmes, including Six Sigma, Slope Steepening, and Advanced Timing Packages. Anthony can be reached at Anthony@idc-pbs.com