Name and Location
Ranger 3 Deeps exploration decline project, Northern Territory, Australia.

Client
Energy Resources Australia (ERA), in which Rio Tinto has a shareholding.

Project Description
In 2009, ERA announced the discovery of a significant uranium oxide orebody in an area known as Ranger 3 Deeps, located east of and adjacent to the current Ranger 3 operating pit.

The ERA board has since approved the construction of an exploration decline to conduct close-spaced underground exploration drilling and explore areas contiguous to the Ranger 3 Deeps resource.

Mining will be conducted through a series of stopes, accessible through a decline, allowing for the transportation of material in trucks to the surface. The decline, constructed as part of the Ranger 3 Deeps exploration decline project, will also serve as the primary access to the underground mine and is located adjacent to Pit 3.

The fixed ventilation system, constructed for the exploration decline project, will also be used for the proposed action and will be expanded to include additional ventilation shafts.

A paste fill plant, about 100 m³/h in capacity, will be constructed within the footprint of the existing operational area for backfilling the mined-out stopes.

The main mine operations will be more than 300 m below surface. Mineralised material will be transported to the surface and processed at the existing processing plant. Owing to the selective nature of the proposed underground mining method, only a relatively small quantity of waste rock – about 500 000 t – will be generated, compared with more than 80-million tons of waste from the mined-out Pit 3.

A brine concentrator will also be installed as part of a significant investment in process-water management and treatment at Ranger 3 Deeps. The concentrator uses thermal energy to evaporate water, which is then condensed and discharged as clean distilled water.

Net Present Value/Internal Rate of Return
Not stated.
 

Value
ERA has reported that it will raise about A$500-million to fund the construction of its Ranger 3 Deeps exploration decline and further the studies in the Ranger 3 Deeps mine.

The proceeds will be used to fund the construction of the A$220-million brine concentrator and other management initiatives, which will cost A$52-million.

The funds will also go towards the construction of the Ranger 3 Deeps exploration decline and associated exploration drilling, at a cost of A$120-million, with a further A$57-million being set aside for the completion of a prefeasibility study (PFS) on the development of the Ranger 3 Deeps mine.

A further A$40-million had been earmarked for an expanded exploration programme, targeting highly prospective areas on the Ranger project area from 2012 to 2014.

Duration
A decision on the viability of the Ranger 3 Deeps development is expected by late 2014.

Latest Developments
ERA announced on June 11 that it would not proceed with the final feasibility study of the Ranger 3 Deeps project in the current operating environment.

Rio Tinto recognises the importance of ongoing rehabilitation work at the Ranger mine site, which is surrounded by the World Heritage-listed Kakadu National Park.  Rio Tinto is engaged with ERA on a conditional credit facility to assist ERA to fund its rehabilitation programme, should additional funding be required beyond ERA’s existing cash reserves and the future earnings from processing ore stockpiles.

Rio Tinto is assessing a potential noncash impairment charge of approximately $300-million (post tax) relating to its shareholding in ERA.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Not stated.

Contact Details for Project Information
ERA, tel +61 8 8924 3500, fax +61 8 8924 3555 or email info@era.riotinto.com.