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

Client
Energy Resources Australia (ERA).

Project Description
In 2009, ERA announced the discovery of a significant uranium oxide (U₃O₈) 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 accessed by a decline, allowing the transportation of material to the surface in trucks. 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 the 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 brine concentrator uses thermal energy to evaporate water, which is then condensed and discharged as clean distilled water.

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 has been earmarked for an expanded exploration programme, targeting highly prospective areas on the Ranger project area between 2012 and 2014.

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

Latest Developments
ERA has lowered the resource estimate at its Ranger 3 Deeps project to 11.9-million tonnes, grading 0.274% U₃O₈, for 32 620 t of contained U₃O₈.

This was compared with the previous estimate of 10.14-million tonnes, at 33% U₃O₈, for 33 297 t of U₃O₈.

The company says that the key change to the previously reported estimate is the reclassification of indicated resource to a distribution of measured, indicated and inferred resource.

The new resource is now estimated at about 8 448 t of measured resource, 14 276 t of indicated resource and 9 896 t of inferred resource.

The final mineral resource estimate for the Ranger 3 Deeps project is scheduled for completion in the fourth quarter of this year, following the completion of the underground drilling programme in the fourth quarter of the year.

The underground project’s PFS is also on schedule to be completed before the end of the year.

ERA recently received federal approval to restart operations at the Ranger mine, in the Northern Territory, after the failure of a leach tank in December last year. Approval from the Northern Territory state government is still required.

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.