An excavator incident has prompted WorkSafe New Zealand to release a safety alert on managing ground instability hazards.
An excavator operator excavating coal was injured when a rock fall occurred and struck the excavator. The victim was in the excavator cab during the time of the incident. WorkSafe is currently investigating.
The safety alert has been issued to remind the extractives industry of the need to ensure effective controls are in place to manage ground instability hazards.
“Ground instability hazards management in mines and quarries is a critical risk area the sector must address through having effective controls which are continuously monitored to ensure they remain effective,” the safety alert stated.f
“All critical risk controls must be understood by all workplace personnel and applied without expectation to ensure everybody’s safety.
WorkSafe says designing a mine or quarry to enable safe product extraction can be achieved through:
- Undertaking a geotechnical assessment to identify the geotechnical properties of the excavation material
- Establishing overall slope design with an appropriate safety factor
- Designing of bench heights and widths
- Optimized orientation of rock faces including identifying failure modes to minimise rock falls
- Design enough space for windrows, rock traps and roads
- Ensuring excavators and other equipment are appropriate for the specific mine layout
“Following the identification of ground or strata instability as a principal hazard, the senior mining operation site executive must ensure a geotechnical assessment is completed by a competent person to determine what ground or strata support level is required for safe mining. They must also ensure there is a principal hazard management plan (PHMP) for ground or strata instability in place.”
More information about this safety alert is available on WorkSafe New Zealand’s website.