Orica was presented with the 390L WEZ 49A block in July 2020. While the block size was typical for a Borden WebGenโข stope, the complexity lied in the geometry. Due to varying stages of completion in the development drifts surrounding the stope, successful extraction would need to be accomplished via drilling on 4 separate horizons, at a multitude of angles. The drilling would consist of a combination of up-holes, down-holes and side-holes from the 390 and 375 levels.
Once the stope reconciliation was completed this stopeโs performance was evaluated as an exemplary success. With targeted recovery of 90% and 15% dilution, the efforts put forth by Newmont, Orica and Redpath resulted in a 98% recovery and 17% dilution. The additional dilution was due to slight overbreak in the hanging wall along a joint set, which is typical of Borden. Minimal broken muck was left sitting on the footwall despite its 43-degree angle, thanks to the enhanced timing and sequencing capabilities of WebGenTM 100. Case study by Orica.
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Case study_Newmont Borden Case Study -Optimising Complex Stope Designs