The Nunavut project now has a probable reserve and pre-feasibility plan, but its study excludes some costs and the regulatory review is paused for more information
Thunder Bay – Mining News Service – A new pre-feasibility study puts the cost of building and expanding the Storm copper project in Nunavut at $164.69 million, giving the remote Somerset Island proposal its first mineral reserve and a more detailed route toward a possible mine.
Aston Bay Holdings Ltd. released the study Tuesday for the project it owns with operator American West Metals Ltd. American West holds 80 per cent, while Aston Bay holds a 20-per-cent carried interest until a decision to mine is made after a feasibility study.
The plan covers four open pits and a processing system that would sort and concentrate ore on site. Concentrate would be stored for most of the year and shipped during an estimated five-week open-water window in early fall. The site is about 120 kilometres south of Resolute and has no grid connection.
Study case and cost gaps
The study reports a probable reserve of 12.58 million tonnes grading 1.20 per cent copper and 3.7 grams of silver a tonne. Mining is modelled for about 8.6 years, while processing of stockpiled lower-grade ore would extend to April 2040.
At base-case prices of US$5.30 a pound for copper and US$50 an ounce for silver, the study estimates an after-tax net present value of $117.1 million and an internal rate of return of 21.5 per cent when all capital is included. The more prominent $165.1-million value in the company release excludes $37.9 million in pre-development spending from the valuation date.
The capital estimate is an AACE Class 4 estimate with a stated accuracy range of minus 30 per cent to plus 50 per cent. The study excludes sustaining capital, a water-treatment plant and most owner’s technical-team costs. Its $9.7-million closure provision is an allowance supplied by American West. The company identifies those exclusions as risks to be addressed in the next study stage.
A financing proposal from Ocean Partners could cover up to 80 per cent of initial capital, but it is conditional on a feasibility study and final documents. It is not committed funding.
Regulatory work remains early
Storm’s exploration permits are valid through 2031, but they do not authorize construction or operation of a mine. The project still needs review under the Nunavut Planning and Project Assessment Act, a Type A water licence and other territorial and federal permits.
The Nunavut Planning Commission found the proposal conformed to the North Baffin Regional Land Use Plan and sent it to the Nunavut Impact Review Board for screening in August. The review is paused while American West prepares more information, which the company says it plans to provide in the fourth quarter. An environmental impact statement would follow.
Aston Bay says engagement has included meetings in Resolute Bay, Taloyoak and Iqaluit. Further work must address Inuit land and resource use, cultural information, permafrost, groundwater, metallurgical variability, year-round fuel storage and the cost of Arctic construction.
The next major technical step is a feasibility study. No mine-development decision has been made, and the projected April 2030 processing start depends on financing, approvals and work that is still incomplete.
