Name and Location
Pilbara copper/zinc project, Australia.

Client
Venturex Resources.

Project Description
An update on the optimisation study being conducted on the Pilbara project has shown that the upper section of the Sulphur Springs deposit is amenable to extraction using an openpit mine rather than the underground methods in the feasibility study completed in 2012.

The preliminary assessment has indicated that mining of a 50-million-tonne openpit can be used to provide feed for the one-million-tonne-a-year processing plant for the first four to five years of the project.

According to the study, openpit mining will be more economical than underground mining and achieve better recovery of the resource within the openpit shell.

There will also be a significant reduction in the amount of development required to establish the underground mine, as the portal of the decline and entries to the ventilation shafts can be located within the openpit.

The capital costs to establish the underground mine will, therefore, be lower and will also be deferred until the fourth year of the project.

Further, the improved recovery of the Sulphur Springs resource, combined with mining inventory, expected to be available from the recently upgraded Kangaroo Caves resource, will extend the current 8.5-year life of the project identified in the 2012 feasibility study.

The process plant and site infrastructure proposed in the 2012 feasibility study have also been reviewed and opportunities for capital cost savings have been identified, including:
– using a semiautogenous/ball mill grinding circuit;
– improving the design criteria for the flotation plant, including deferral of the lead circuit to treat ore from Whim Creek and Mons Cupri late in the life of the proposed project;
– simplifying the handling of concentrates;
– eliminating the filtration of tailings to produce paste fill and dry stacking of tailings; and
– deferring the high-cost paste fill plant until Year 5 of the Project.

A high-density polyethylene-lined conventional tailings dam with under-drainage, located adjacent to the processing plant, to replace the equipment associated with the dry stacking of tailings and the evaporation pond contemplated in the 2012 feasibility study, is also being designed. This will result in improvements in the operability of the contemplated processing plant and ongoing operating cost savings.

Net Present Value/Internal Rate of Return
Not stated.

Value
Not stated.

Duration
Not stated.

Latest Developments
The optimisation study was on track for completion by the end of October 2015.

Key Contracts and Suppliers
Entech (review of mine plan) and Lycopodium Minerals (review of process plant and site infrastructure).

On Budget and on Time?
Not stated.

Contact Details for Project Information
Venturex Resources, tel +61 8 6389 7400, fax +61 8 9463 7836 or email admin@venturexresources.com.
Entech, tel +61 8 6189 1800 or email admin@entechmining.com.au.
Lycopodium Minerals, tel +618 6210 5222 or fax +618 6210 5201.