In one incident an underground nipper, or 4WD utility, reversed into a drilling jumbo on a decline.

The nipper was being reversed down the decline when the driver parked the vehicle up on a grade 6-8m away from the jumbo.

After leaving the vehicle in gear the driver left the cab but failed to put chocks behind the wheels. The nipper rolled down the hill and crashed into the jumbo.

To make matters worse the driver failed to preserve the accident scene.

He was medically assessed after the incident and subjected to a drug and alcohol test, which he passed.

The Regulator said mine operators should always comply with correct park-up arrangements, particularly when parking on grades.

Accident scenes should also be preserved until the Regulator could attend the scene or has given permission for the scene to be cleared.

Another underground nipper driver also found himself in a spot of bother when reversing out of a workshop onto a decline after the left rear wheel of his vehicle hit a pillar, causing it to drive up the pillar wall and fall onto its side.

The nipper happened to be the mine's explosive vehicle.

Fortunately it was not carrying any explosives at the time.

No injuries were sustained in the incident, with the scene again not preserved as required.

The Regulator said vehicles should always be driven at speeds appropriate to the conditions.

It also reminded operators to always preserve an incident scene until the department attended or gave permission for the scene to be disturbed.