Underground Aggregate Mining Short Bench Blasting Technique
Mike Koehler (ISEE)
This presentation highlights a cost effective technique for vertical bench blasting at underground aggregate mining operations. After driving the horizontal advance, the mine in this case study develops a second vertical bench that is approximately seven meters deep. Historically, the vertical bench was drilled and blasted to full depth in one cut. The short benching technique is to blast the vertical bench in two separate lifts. The first lift is drilled only three and a half meters deep and is mucked out and scaled after the blast. Although several line items are increased, such as drill set-up time, the shorter bench program has provided substantial cost savings. This technique speeds the drilling process by eliminating the need for the driller to change steels. Additionally, short benches have provided a vast reduction in scaling time, and notably reduced pillar damage.
Keywords:
Underground Mining, Vertical Bench, Cost Effective, Blasting, Explosives, Aggregate
