The management practices employed by the Drill and Blast team to prevent adverse overpressure or vibration impacts from blasting include:
- Detailed drill and blast designs, procedures, supervision, ongoing training and competency assessment of personnel in all drill and blast activities.
- Innovative training and use of technology to continually improve blast practices for example:
- Using a total data management system for blasting; which includes input of actual blasting data to refine and calibrate site laws for overpressure and vibration
- Utilization of Advanced Vibration Modelling Software to assist with reduction in vibration at sensitive receptors.
- Best drilling practices are followed to ensure adequate drill bench preparation, on drill GPS location of the drill holes, hole savers to reduce the amount material fallback and the completion of drilling records including drilled depth and nature of the strata.
- During explosive loading, shotfirer's checks are undertaken to prevent the overloading of explosives and under loading of stemming that can lead to increased overpressure or vibration;
- The presence of water in blast holes can lead to the generation of fume. Explosive product selection based on several factors is critical to limit fume generation.
- The blasts are initiated by Nonel (non electric) or electronic detonation. Nonel detonators are most commonly used, however electronic detonators are increasingly used by Ravensworth Operations where decking and exact timing of the shots are required to minimise vibration for sensitive receptors.