On 22 November 2006, ammonium nitrate was being transferred into a silo storage facility at a mine site by means of a belt-driven bucket elevator.
During the transfer operation, a ram solenoid valve failed to fully reposition a diverter gate used to direct ammonium nitrate between silos. This led to ammonium nitrate backing up, then falling down the elevator shaft and bogging the bucket elevator.
The drive pulley of the belt-driven bucket elevator continued to rotate even though the elevator was bogged, resulting in slippage and the generation of sufficient heat to cause the belt to catch fire.
The facility was promptly shut down, the fire extinguished and the area cooled with water.