The Deposit and it’s History

The Beverley deposit contains approximately 21,000 tonnes of uranium and was formed over millions of years as uranium from the radioactive mount Painter Region of the north-west Flinders Ranges was transported to lake Frome in streams and rivers. The orebody then became contained as impervious rock layers formed above and below the deposit, and for 40 million years it laid undisturbed. The ore zone is now located approximately 100 metres beneath the surface making it relatively easy to access for mining purposes. The hydrogeology is quite favourable for an ISL mine as the deposit lay in an aquifer, composed of sandy sediments with two clay layers of impermeable rock above, below and surrounding the aquifer, which contains the ore zone and only allows for lateral movement within the aquifer. Such a characteristic becomes important and helpful when it comes to environmental health and safety aspects.

The Mining Process

As already stated the Beverley Uranium Mine operates as an In Situ Leach mine, and consists of well fields and a processing plant. Quite simply, it is a water pumping activity. Water is transported from the plant to injection wells and pumped down to the aquifer. This water is chemically treated to have a lower pH than the water in the aquifer and it is this characteristic that causes, through a series of chemical reactions, the uranium to dissolve into solution. This uranium-rich water is then pumped back up the recovery well and returned to the plant for treatment. At the plant, the uranium is separated from the solution by running it through columns containing resin, which serve to capture the uranium. This process is then reversed, re-dissolving the uranium into solution and then this water is chemically treated to produce a flaky solid deposit of uranium. The water is removed and this "yellow cake" is then placed in drums and sealed, and shipped away. Further treatment is conducted before the uranium is used as fuel in nuclear reactors.

Environmental impact and safety

A number of measures have been taken by Heathgate Recourses to ensure that the mining process remains a safe and environmentally friendly operation. Some of these include:

• Regular sampling of existing bores and water courses around the mine will be monitored so that any change in the water quality can be detected
• Monitors posted throughout the mining locality will detect any change in radiation activity, through the detection of radon, a naturally occurring gas resulting from groundwater, containing uranium deposits, being released to the surface.
• Workers are subject to tests before they leave the site to ensure they are not carrying trace amounts of contamination and the air around the site will be tested for these contaminants.
• The liquid residue produced in ISL operations is either evaporated or eventually returned back to the original aquifer and the solid residue (some solids generated while concentrating the uranium, gloves, coveralls and used pumps and other disposable items) is contained in specialised earthen cells deigned to ensure any existent radiation does not leak out into the environment.
• The plant, well fields and camp, which will house the 120 workers employed on a roster basis, will be the only form of infrastructure on the mine site and will be dismantled and removed once the mining process is over. The water required for use on the camp will be drawn from the Great Artesian Basin located a further 200 metres deeper than the aquifer.
• The State and Federal government departments ensure that strict environmental and worker safeguard policies are upheld and that the uranium produced is used only for peaceful purposes.