OZ Minerals
Sustainability Report 2014


The Carrapateena copper-gold project in South Australia continues to demonstrate its quality.

In 2014, a pre-feasibility study for Carrapateena was completed. This demonstrated that the Carrapateena project is both technically and financially viable and offers the potential of multi-decade production at low operating costs. An initial Ore Reserve estimate, which underpins a 24-year mine life, was also declared.(1)

Key project points include:(2)

  • Average annual production rate of 114,000 tonnes of copper and 117,000 ounces of gold.
  • Long mine life of 24 years based only on Reserves.
  • Ore-body will cave with pre-conditioning, as confirmed by three independent geotechnical consulting firms.
  • Demonstrated ability to produce a high quality copper-gold concentrate averaging 30–35 percent copper over life of mine with uranium and fluorine below typical penalty levels and no arsenic.
  • High metal recoveries of 92 percent and 70 percent for copper and gold, respectively.

OZ Minerals has committed to undertake two key initiatives aimed at maximising the value of its Carrapateena copper assets.

In early 2015, OZ Minerals announced an infrastructure partnership with the South Australian Government to open up future opportunities through joint development of infrastructure. A scoping study completed in 2014 identified significant potential benefits, including potential lower development costs, from the development of new rail infrastructure to transport Carrapateena ore to the existing high-quality processing plant at Prominent Hill.

Following on from this, a rail infrastructure pre-feasibility study has been commissioned to develop this concept. As part of this work, an evaluation of third party build/own/operate financing of the rail will be undertaken, which could see significantly lower upfront capital required to develop Carrapateena. The study is expected to be completed during 2015.

The second project will investigate the concentrate treatment process. The Carrapateena pre-feasibility study anticipates a high-quality concentrate grade of 30–35 percent. A pilot plant hydrometallurgical process, conducted in 2014, successfully demonstrated the ability to substantially increase copper in concentrate to 55–60 percent copper, along with a significant reduction in deleterious elements, making it an even higher quality premium-carrying concentrate for smelters. To test the scalability of this process, a demonstration plant trial will be undertaken in 2015 by OZ Minerals. The demonstration plant trial will cost $18 million, some of which will be funded through the partnership with the South Australian Government.

Both the rail infrastructure project and hydrometallurgical demonstration plant initiatives have the potential to improve the value or composition of any partnership stake in the development of Carrapateena. As such, the data room and partnering process run in 2014 has been suspended until these initiatives are completed and the results then integrated in the Pre-Feasibility Study.

(1) The information in this report that relates to the Ore Reserve estimate for Carrapateena at 15 August 2014 is extracted from the report entitled ‘Ore Reserve for Carrapateena underpins low operating cost, long life operation’, released on 18 August 2014 and is available to view at www.ozminerals.com/operations/ resources--reserves.html. OZ Minerals confirms it is not aware of any new information or data that materially affects the information included in the original market announcement and, in the case of estimates of Ore Reserves, that all material assumptions and technical parameters underpinning the estimates in the relevant market announcement continue to apply and have not materially changed. OZ Minerals confirms that the form an context in which the Competent Persons’ findings are presented have not been materially modified from the original market announcement.

(2) All amounts are projected as detailed in the Carrapateena Pre-Feasibility Management Summary, released on 18 August 2014 and is available to view at http://www.ozminerals.com/news/asx-releases.html.

75 percent of our workforce lives in South Australia.