Uranium Mining
In July 2007, after discussions between WA Surface Mining and Nova Energy Ltd, an agreement was reached to conduct a mining trial on Nova's mining lease located near Wiluna, Western Australia. The trial was conducted over a two-week period using a surface miner owned and operated by WASM.
The trial was conducted in two locations approximately one kilometre apart at the Centipede Uranium Deposit located forty kilometres south of Wiluna. The trial pits were first stripped of overburden by means of a front end loader and bulldozer. The surface miner was then set to mill to a depth of 200mm in parallel runs 2.2 metres wide, with the depth of the cut being controlled by a laser on one side of the machine and an internal slope control on the other side.
For the duration of the trial the cutting speed of the surface miner averaged 13 metres per minute, giving a production rate of approximately 550 tonnes per hour.
After mining down approximately 1 metre in the second location, the surface miner encountered the top of the water table. The surface miner continued mining within the water table with no effect on production rates.
Prior to starting the trial, a prototype gamma radiation detector (commissioned by Nova Energy) was fitted to the surface miner to assess the quality of the ore as it was being mined. This proved to be a great innovation. In full production it is envisaged that the surface miners will be operated with conveyors loading the mined product directly into trucks. With the aid of a gamma radiation detector, the operator will be able to grade the ore as s/he loads each truck. The overall benefit of this is an increase in the efficiency of the process plant; the feed stock grade can now be managed much more accurately and easily right at the pit floor.