Name of the Project
Deflector gold/copper project.

Location
Australia.

Client
Doray Minerals.

Project Description
A detailed review has confirmed a high-grade, low-cost project, with robust financials and significant upside.

Mining at Deflector will initially comprise openpit mining, transitioning to an underground operation towards the end of the first year.

The Western and Central lodes at Deflector are steep mineralised structures, dipping between 80° and 90°, typically from 1 m to 5 m wide and hosted within a competent basalt host. The total strike length of the orebody is about 850 m.

Openpit mining will occur in stages, initially focusing on mining the narrower Central lode pit.

Underground access will be gained through a portal established in the Central lode pit at a depth of 35 m below the surface. Mining of the wider Western lode pit and the smaller Northern pit on the Central lode will then continue to a maximum depth of 85 m, concurrent with underground mining.

Following the establishment of the portal, underground mining will be carried out using a conventional sublevel long-hole open stope mining method at 20 m sublevel intervals.

Underground ore access will be gained through a 5.3 m × 5.5 m decline to mine 3.2 m × 4 m- and 4 m × 4 m-ore development drives to suit lode widths.

The decline and level access development is located centrally between the Western and Central orebodies. Underground mining is currently planned to 270 vertical metres below a 15 m crown pillar, limited only by current drilling depth.

The top-down mining method, retreating to a centrally located access crosscut, allows for stoping to start as soon as level development has been completed. Any ore remaining within a stope can then be extracted from a lower level, ensuring minimised ore loss because of mining.

Rock mass characteristics assessed by two specialist geotechnical consultants found the basalt host rock to be competent, with high strength (uniaxial compressive strength averaging 250 MPa). Full-depth rib pillars will be left at appropriate intervals in accordance with geotechnical recommendations.

Doray will build a new processing plant at Deflector, which is specifically designed to suit the metallurgy of the orebody.

The plant will comprise three-stage crushing and screening, a ball mill, a gravity circuit, an elution circuit and a gold room, as well as a flotation circuit.

The fit-for-purpose plant will be built adjacent to the orebody to minimise mine haulage costs from the openpits and underground.

The plant will average 454 000 t/y, with expected average recoveries of 89.5% for gold and 93% for copper from the primary ore, which provides 82% of total ore feed for the plant. Based on these recoveries, the project will produce an estimated 61 000 oz/y of gold or about 74 500 oz/y on a gold-equivalent basis.

Doray will use the existing tailings storage facility (TSF) at the Gullewa mine site, with tailings to be transferred from the new Deflector plant using a purpose-built pipeline. Two further pipelines will supply raw water from an existing bore field, supplemented by a pipeline that recycles water from the existing TSF for use in the processing plant.

Site offices, a workshop and stores will be located in close proximity to the mine, along with the power station, fuel farm and underground mining contractor facilities.

The company plans to build a new accommodation village within 1 km of the mine, minimising the level of traffic on the Deflector access road and integrating medical services and administrative management of the mine site and village.

Jobs to be Created
Not stated.

Net Present Value/Internal Rate of Return
The project has an internal rate of return of 28%, with a payback of 3.2 years.

Value
Preproduction capital is estimated at A$67.6-million.

Duration
The start of production is expected in the fourth quarter of the 2016 financial year.

Latest Developments
Doray has officially opened its Deflector gold project within 14 months of acquiring the project.

Deflector is currently in a ramp-up phase and is progressing through the orebody’s oxide and transitional levels before reaching the primary underground ore in early 2017.

Key Contracts and Suppliers
GR Engineering Services (processing plant).

On Budget and on Time?
Not stated.

Contact Details for Project Information
Doray Minerals, tel +61 8 9226 0600, fax +61 8 9226 0633 or email info@dorayminerals.com.au.