Contractor fined $540,000 after fatal rock fall

An underground mining contractor has been fined for a rock fall incident that resulted in the death of an employee at Hamlet underground gold mine in WA in October 2022.

The contractor, RUC Mining Contractors, pled guilty to two counts of the same offence — exposing a worker to a risk of death, injury or harm to health, contrary to sections 19(1) and 32(1) of the Work Health and Safety Act 2020 — which resulted in the death of a driller and the injury of a probationary offsider.

This offence does not indicate that the breach caused the fatal incident, however, it highlights a failure in relation to risk management, according to the WA Department of Local Government, Industry Regulation and Safety.

RUC Mining Contractors, which Gold Fields had engaged to conduct raise bore-drilling work at the Hamlet mine — part of its St Ives gold mine — was given a single fine for the two counts.

Prior to the accident, the RUC Mining Contractors-employed driller and probationary offsider were engaged in disassembling a reamer by unbolting and removing wings attached to the reamer’s centre box at the base of a ventilation shaft.

Reamers must be disassembled and removed from the holes they create. At the time of the fatal incident, the disassembly method that contractors employed involved pulling the reamer’s head to the side of the raise and rotating its head to position its worked-on parts beneath supported ground and behind protective curtains.

Because the reamer was not centred in the hole, workers were experiencing difficulties hanging the curtains and draping them over the reamer’s head. To enable the centring of the reamer in the hole, an employee booked a jumbo operator to install a torque plate on the ventilation shaft’s right-hand wall and, in the meantime, disassembly work continued.

During that period, the contractor’s area manager visited the mine and observed that the protective curtains were not properly installed before instructing the driller to climb off the reamer as they were working too close to the curtains directly beneath the hole and beneath unsupported ground.

The fatal incident occurred about an hour after the area manager left the ventilation shaft. The driller was standing on top of the reamer’s head, undoing bolts on its top. The probationary offsider was standing on the ground close to the reamer’s edge, feeding the driller the air hose for the rattle gun they were using. The driller was standing under unsupported ground as a rock fall happened, striking the driller and causing the probationary offsider to fall to the ground. The driller died instantly and the probationary offsider suffered minor physical injuries and a psychological injury.

WorkSafe Commissioner Sally North says this tragic incident is a reminder that raise-boring activities can involve serious hazards, not only from rock falls but also from equipment failure, ground failure and the inrush of mud, drill cuttings, water or gas.

“I encourage all mining operators and contractors involved in raise-boring activities to ensure a safe system of work is in place to ensure risks have been eliminated or minimised, and that workers are consulted on the procedures, equipment and training,” she said.