The wall, which had an estimated weight 7.4 tonne and was part of the surface crushed stone (precoat) load-out bins, collapsed onto an adjacent stacker conveyor leg.

The conveyor then collapsed. Prior to the incident two employees were working in the vicinity of the conveyor and stacker.

“The designers of a structure must also supply adequate information to the mine operator to ensure that the construction, installation and commissioning of such structures is undertaken so as to meet the intended purpose for which it was designed,” NSW Mine Safety said.

“This may include results of calculations and conditions for use.”

In another incident, a strain burst caused by a seismic event in the localised region resulted in fall of supported ground at a NSW mine.

The event was detected by the mine’s seismic monitoring system. It was a low traffic area, but it was possible a person could have been walking near the affected area and was regarded by Mine Safety as a high potential incident.

“Mine operators must ensure that mining induced seismicity is appropriately monitored, recorded, and the data analysed and interpreted,” Mine Safety said.

“Stress modelling should be undertaken in order to predict seismically active zones. The design and reviews of ground support regimes should consider the likelihood of rock bursts and the requirements for yielding and appropriate surface support.”