Name of the Project
Cosmos Odysseus nickel project.

Location
Odysseus is located on a granted mining lease that is part of the high-grade Cosmos nickel complex, which is situated 30 km north of Leinster, in Western Australia.

Client
Western Areas.

Project Description
A definitive feasibility study (DFS) has confirmed the Cosmos Odysseus nickel project as a robust, ten-year operation producing 130 000 t of contained nickel in concentrate from ore reserves of 8.1-million tonnes at a nickel grade of 2%.

Odysseus will be accessed through a new single ramp decline that starts from the existing AM5/6 decline development. Compared with the central spiral decline proposed in the 2017 prefeasibility study (PFS), the ramp decline from the AM5/6 infrastructure minimises the full-face development required to access the Odysseus orebodies, reducing the development timeframe by six months months compared with the PFS.

While the existing decline development will need to be rehabilitated to a relatively lower take-off point, since it passes directly through existing AM5 infrastructure, it also creates the option of potentially mining the AM5 and AM6 deposits, which contain an indicated mineral resource of 2.2-million tonnes grading at 2.6% nickel. (No evaluation nor study has been completed for the AM5 and AM6 deposits, and any potential benefits do not form part of the Odysseus DFS. Early, concurrent and later mining options will form part of further study work).

The primary mining method will be single-lift long-hole open stoping with paste fill accessed through transverse ore drives (west to east) on a 50 m cross cut spacing. The South and North orebodies will be mined in a top down, centre-out sequence. Compared with the PFS, which had proposed a bottom-up approach, the top-down approach combined with the quicker ramp access enables earlier access to ore.

The existing Cosmos processing plant will undergo a $36-millon expansion and refurbishment to increase mill throughput from its previous nameplate capacity of 450 000 t/y to 900 000 t/y.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The project has an estimated pretax net present value, at a 7% discount rate, of $418-million and internal rate of return of 28% at $7.50/lb nickel price, with a 3.5-year payback from the start of production.

Value
Preproduction capital expenditure is estimated at $299-million, including contingency.

Duration
First nickel concentrate is scheduled for the December 2022 quarter.

Latest Developments
The Western Areas board has approved a decision to mine, with Odysseus expected to continue the separate early works programme announced in April 2018, which is forecast for completion in July 2019.

Key Contracts and Suppliers
GR Engineering Services (process plant design, engineering, associated infrastructure); Piran Mining (mine planning and optimisation); KCSA Geomechanics (geotechnical engineering); Golders (geotechnical engineering); Dempers & Seymour (mining rock mass modelling); Itasca Australia (geotechnical modelling and geotechnical peer review); RSV SA (shaft engineering and design); Outotec (paste fill engineering, plant design and testing); OZ Vent (mine ventilation); ALS Metallurgical Services (metallurgical testwork); Groundwater Resource Management (hydrogeology); Big Dog Hydrogeology (hydrogeology peer review); MYR Consulting (risk assessment); Mining Access Legal and MMTS (tenement management services); SRK Consulting (geological model); Project Support (mining tender and infrastructure cost management); and Project Consultancy Services
(power study).

On Budget and on Time?
Too early to state.

Contact Details for Project Information
Western Areas, tel +61 8 9334 7777, fax +61 8 9486 7866 or email info@westernareas.com.au.