Vancouver-based Aris Mining has announced positive results from a preliminary economic assessment (PEA) for its 100%-owned Toroparu gold project, in Guyana, confirming the asset as a large-scale, long-life openpit operation with strong returns and expansion potential.

The PEA outlines a 21.3-year mine life with average gold production of 235 000 oz/y and a post-tax net present value (NPV) of $1.8-billion at a gold price of $3 000/oz. The study indicates an internal rate of return of 25.2% and a payback period of three years from first production.

Aris Mining CEO Neil Woodyer said on Tuesday the study highlighted Toroparu as a key growth and diversification opportunity for the company. “After the GCM Mining and Aris Gold merger and the arrival of our management team in September 2022, we paused the project’s previous construction plans to reassess it on a first-principles basis. The result is a robust PEA that establishes a solid path forward,” he said.

The openpit operation is designed as a conventional truck-and-shovel mine with a 7-million-tonne-a-year mill capacity, supporting low-cost production and extending mine life beyond 20 years. Measured and indicated resources total 126.9-million tonnes at 1.30 g/t gold for 5.3-million ounces, with an additional 1.2-million ounces in the inferred category.

Over its life, Toroparu is expected to produce 5-million ounces of gold, 4.9-million ounces of silver, and 260-million pounds of copper, with by-product credits helping achieve low life-of-mine (LoM) cash costs of $826/oz and all-in sustaining costs of $1 289/oz. The company estimates LoM payable gold sales of $14.7-billion at the base case gold price.

Initial construction capital is projected at $820-million, including $96-million in contingency. Aris Mining expects to reduce upfront funding to $682-million by leveraging $138-million from an existing precious metals streaming agreement. An additional cost benefit stems from a fleet leasing strategy, with the initial mining fleet to be secured through original equipment manufacturer (OEM) lease financing.

The leasing arrangement, covering excavators, haul trucks, and support equipment, will include long-term maintenance and parts supply agreements to ensure operational reliability. “By structuring equipment procurement under OEM leases, we gain access to modern, well-supported machinery while minimising upfront capital commitments,” the company said.

A preproduction stockpile of 6.1-million tonnes, equivalent to nearly a year’s mill feed, will be built during construction to support a smooth startup and ramp-up to nameplate capacity within the first year of operation.

Aris has also opted to incorporate a flotation circuit from the outset to efficiently manage copper in the mill feed while generating a valuable by-product stream. Previous project iterations had deferred this circuit to cut initial costs, but the new design enhances revenue potential and metallurgical control.

The openpit design was based on a conservative $1 950/oz gold price and a 0.45 g/t cutoff grade, leaving room for further resource growth in a higher price environment.

Following the strong PEA results, Aris has started a prefeasibility study (PFS) for Toroparu, targeting completion in 2026. Woodyer said the company’s technical pipeline - with the Toroparu PEA and the Soto Norte PFS both completed this year - underscores the depth of Aris Mining’s growth portfolio beyond its Segovia and Marmato operations in Colombia.

“We are building a strong foundation for Aris Mining’s future, supported by disciplined technical studies and a diversified asset base across Latin America,” he added.