PERTH (miningweekly.com) – The Frieda River copper/gold project, in Papua New Guinea, could produce more copper and gold over a longer period than previously thought, ASX-listed Highlands Pacific reported on Monday.

Highlands, which owns a 20% interest in the joint venture (JV) project, told shareholders that partner PanAust had finalised the scope of an updated feasibility study for Frieda River, incorporating significant changes to the 2016 study.

PanAust noted that the revised scope of the project supported a mine life of more than 30 years, and greater extraction of the extensive mineral resource of the project, by leveraging third-party shared-use infrastructure.

A 2016 feasibility study estimated that the Frieda River project could produce 175 000 t/y of copper and 250 000 oz/y of gold over 17 years, based on a large-scale openpit mining operation, that would cost some $3.6-billion to develop.

PanAust said that the new project scope, which supported Papua New Guinea’s regional and development objectives, comprised a land-based logistics and infrastructure corridor connecting the mine to the Vanimo Ocean port, and a long-life, large-scale openpit copper/gold mine.

The project will also consist of a conventional comminution and flotation process plant treating more than 40-million tonnes a year of ore, producing some 290 000 t/y of copper and 360 000 oz/y of gold at its peak.

The ore will be transported via a 320-km buried pipeline to the Vanimo Ocean port for export to customers, while low-cost renewable energy from a hydroelectric power facility will be used, with water to be supplied from the ISF reservoir.

The hydroelectric power is expected to assist the country in meeting its target of 100% renewable energy supply by 2050.

The hydroelectric facility will operate beyond the life of the project, supplying surplus power to the Sepik region, which currently lacks both substantial generating capacity and a transmission grid, PanAust said.

To leverage the infrastructure established for the project, PanAust has identified opportunities to further extend the mine life, and extract copper and gold from the Nena deposit, in addition to the Horse-Ivaal-Trukai, Ekwai and Koki deposits currently under consideration.

The updated feasibility study, and the associated environmental-impact statements, will be completed by the December quarter, PanAust said, prior to lodging amendments to the special mining lease application, and associated permits.