The Goro nickel-cobalt mine is a fully-integrated mining operation involving an open-pit mine, a processing plant and a port facility in the French island territory of New Caledonia in the South Pacific.
Owned and operated by Vale Nouvelle-Calédonie (VNC), a subsidiary of Vale, the Goro mine has been producing since 2010. The total investment for the project is estimated to be approximately £3.5bn ($6bn).
Vale holds a 95% stake in the Goro nickel-cobalt project while the remaining 5% is held by Société de participation minière du Sud calédonien (SPMSC), which is a holding company of three provinces of New Caledonia.
Sumic Nickel Netherlands, a joint venture of Japan’s Sumitomo Metal Mining and Mitsui earlier held a 21% stake in the project which was transferred to Vale in 2016.
Vale announced its intention to exit the Goro nickel-cobalt operations in December 2019, while Australia-based New Century Resources (NCZ) entered into a 60-day exclusivity period with Vale to conclude negotiations for acquiring the 95% stake in the project in May 2020.
The Goro mine produced 23,400 tonnes (t) of nickel and 1,703t of cobalt treating approximately 2.5 million tonnes (Mt) of ore in 2019. The annual design production capacity of the project is estimated to be up to 60,000t of nickel and up to 5,000t of cobalt.
Location and geology
The Goro nickel-cobalt mine is located on the Goro plateau in the southern part of the Grand Terre Island that forms part of the New Caledonia archipelago Caledonia in the South Pacific.
The New Caledonia group of islands are located approximately 1,500km east of Australia in the south-western Pacific Ocean.
The Goro deposit comprises two types of oxidised ore underlying 15m-thick sterile rocks on the surface. The upper part of the deposit predominantly composed of iron oxides-rich lateritic ore, while the magnesium-silicates (saprolite ore) are found in the lower part of the deposit.
The Goro plateau is believed to hold one of the biggest nickel and cobalt-containing laterite deposits in the world.
Nickel and cobalt reserves at Goro
The Goro mine is estimated to hold 122.3Mt of proven and probable reserves grading 1.42% nickel and 0.11% cobalt.
Mining and ore processing
Goro is a conventional open-pit mining operation with hydraulic excavators and bulldozers being used to extract laterite and saprolite ores from the deposit. The extracted ore is hauled by a fleet of dumper trucks.
After screening and grinding, the mined ore is mixed with water to create a combined pulp of limonite and saprolite. The pulp is then conveyed through an 8km-long pipe to the autoclave at the processing plant.
The high-pressure acid leach process is employed to treat limonitic and saprolitic laterite ores for the production of nickel oxide, nickel hydroxide, and cobalt carbonate.
The final products are packed into containers and are trucked to the Vale-operated Prony port facility located approximately 4km away from the processing plant.
The electricity for the Goro mining operations is supplied through the national electricity grid and by independent producers.
The port facility located in the Prony Bay, in Sud province of New Caledonia has three terminals, including a passenger ferry terminal, a dry bulk wharf capable of accommodating 55,000 DWT vessels, and a general cargo wharf that can accommodate 200m-long vessels.
A joint venture between SNC-Lavalin and Foster Wheeler was contracted to provide engineering, supply, and management services for the construction of the Goro-Nickel project.
Goro Construction Team (GCT) comprising Inco, Hatch, and Technip was the project manager, while Golder Associates was engaged as a design consultant for the project.
AG&P was contracted for the engineering, fabrication, supply, and pre-commissioning of modules for the Goro nickel-copper processing plant.
AECOM provided port planning and engineering support services for the project.
VINCI Construction was engaged for the construction of port facilities as well as a 60m-tall tailings storage facility for the project.
Wagner was the concrete supplier for the foundations for processing plants, wharf, tunnels, dams, and general civil works for the project.
Other contractors and suppliers engaged in the project included Roadbridge, FLI International, Solmax, and Rema Tip Top.