Name of the Project
Windfall gold project.

Location
Abitibi greenstone belt, Québec, Canada.

Project Owner/s
Osisko Mining.

Project Description
A preliminary economic assessment (PEA) has provided a robust base case assessment for developing the Windfall gold deposit as an underground dual-ramp-access mine, with a central processing mill at the site.

Potential Job Creation
About 400 direct jobs and 200 indirect jobs will be created during operation, and more than 500 jobs during construction.

Net Present Value/Internal Rate of Return
The project has an estimated pretax net present value, at a 5% discount rate, of C$2.6-billion and an internal rate of return of 50.6%, with an after-tax payback of 2.2 years from the start of production.

Capital Expenditure
The project will require capital expenditure of C$543.5-million.

Planned Start/End Date
The company aims to start production in 2024.

Latest Developments
Osisko will independently develop the Windfall project, after announcing that joint venture (JV) negotiations with Australia’s Northern Star concluded without an agreement.

The company has stated that “the development of the project on an independent basis would be optimal for shareholders.”

Osisko has noted that it has maintained a mutually beneficial relationship with Northern Star as a debt holder through its $154-million in convertible senior secured debenture, due December 2025, with a 4.75% a year interest rate.

The company updated the mineral resource estimate for Windfall in January, stating that it had 3.2-million ounces of measured and indicated resources averaging 10.5 g/t gold and 3.6-million ounces of inferred resources averaging 8.6 g/t gold. 

The resource estimate, which reflects 1.7-million metres of drilling, is a strong foundation for the upcoming feasibility study.

Key Contracts, Suppliers and Consultants
A2GC (rock mass characterisation and rock engineering, in support of the underground mine design); BBA Inc (historical data review; current and historical geology, exploration, drilling; sample preparation, quality assurance and control and data verification; geological modelling and mineral resource estimate; metallurgical testwork management and analysis, crusher and process plant mass and water balance; crusher and process plant design, capital costs and operating costs; electrical infrastructure design and costs; information technology and communications infrastructure design and costs; integrated remote operations centre design and costs; general and administration operating costs; financial analysis and overall NI 43-101 integration); Entech Mining (underground mine design, underground infrastructure, ventilation, production scheduling, underground capital costs and operating costs); Golder Associates (waste rock, tailings, and ore geochemical characterisation; surface tailings management facility designs and costs; site-wide water balance; hydrogeology and groundwater quality input into environmental studies; hydrogeology input for underground mine design); WSP Canada (design and costs of surface infrastructure for Windfall site, site utilities, on-site roads and pads, site infrastructure electrical distribution, surface mineralised material, waste rock, overburden and topsoil management facility, surface water management infrastructure, tailings filtration plant and dry tailings storage/handling, as well as underground paste backfill distribution and infrastructure design and costs); GCM Consultants (water treatment design, capital and operating costs).

Contact Details for Project Information
Osisko Mining, tel +1 416 363 8653 or emailinfo@osiskomining.com.