drc

Its full steam ahead for dual-listed copper/cobalt mine developer Ivanhoe Mines’ Kakula copper project in the Democratic Republic of Congo (DRC).

Underground development is ahead of schedule, and the process plant is planned for completion in Q3, 2021.

As of February, more than 8 km of underground development had been completed at Kakula, which at the time was already 1.7 km ahead of plan.

This article first appeared in Mining Review Africa Issue 4, 2020
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The underground development work at Kakula is being performed by mining crews operating large-capacity, semi-autonomous mining equipment, such as jumbo drilling rigs and 50 t trucks.

Mine access drives 1 and 2 − interconnected, parallel tunnels being developed from Kakula’s main northern declines that will provide access to Kakula’s high-grade ore zones − continue to make excellent progress.

The two south perimeter drives – being developed from Kakula southern decline – are also progressing ahead of schedule and have each been advanced more than 250 m from the bottom of the decline.

The development ore is being transported to surface and stored on pre-production stockpiles, which are expected to grow to approximately 1.5 Mt of high-grade ore and an additional 700 000 t of material grading approximately 1% to 3% copper prior to the start of initial production in Q3, 2021.

Based on the results of the February 2019 Kakula pre-feasibility study, the project’s average feed grade over the first five years of operations is projected to be 6.8% copper, and 5.5% copper on average over a 25-year mine life.

In parallel with the construction of Kamoa-Kakula’s phase 1 Kakula mine, work is progressing on the independent Kakula definitive feasibility study (DFS) and an updated integrated development plan for the entire Kamoa-Kakula mining complex, which is expected to be issued in mid-2020.

Process plant and other surface infrastructure on track

Kakula’s original 3 Mtpa first processing plant module has already been redesigned during the basic engineering phase to a nameplate capacity of 3.8 Mtpa. Purchase orders have been placed for all major long-lead time mechanical equipment, plant earthworks is complete, and plant civil works are advancing rapidly.

The contract for the SMPP (structural, mechanical, piping and platework) supply and erection portion of the plant construction has been awarded and steel fabrication is underway.

The capital cost estimate related to the construction of the mining infrastructure (underground and surface), processing plant and surface infrastructure has been estimated to a basic engineering level of accuracy and is being used as the control budget estimate for the project.

The current updated estimate of the project’s initial capital costs is approximately US$1.3 billion as of 1 January 2019, which assumes commissioning of the first processing plant module in Q3, 2021 and includes expanded plant capacity and pre-production ore stockpiles.

Other engineering and construction activities underway at Kamoa-Kakula include the refurbishment of six turbines at the Mwadingusha hydro-electric power plant and associated 220 kV infrastructure to supply the mine with clean hydropower, finishing construction of a permanent road between the mine site and the Kolwezi airport, construction of the first phase of accommodations for 1 000 employees and contractors, and other surface infrastructure.

More than 4 400 employees and contractors currently are helping to construct the new Kakula mine, of which approximately 90% are Congolese nationals.

“We’re not just investing in a new mine, roads, hydropower plants, power lines and other important infrastructure, we’re investing in good-paying jobs and new opportunities for people who live in the DRC. And with our focus on skills training and apprenticeships for young Congolese, we’re helping build the DRC’s next generation of skilled tradespeople,” says Mark Farren, CEO, Kamoa Copper SA.

Kamoa-Kakula focused on producing “green copper”

Together with its joint-venture partners, Ivanhoe is committed to building modern, safe, mechanised mines that will be showcases for responsible, “green” mine development.

“These vast Kamoa and Kakula discoveries are the type of world-scale mineral systems needed to supply the copper for the electrification of the global economy, to usher in the era of the electric car, and the electric everything, in order to reduce our planet’s consumption of hydrocarbons,” says Ivanhoe Mine’s co-chairman Robert Friedland.

“In a world deeply concerned with the unabated generation of global warming gases throughout the supply chain, many people of influence in the world’s financial community are becoming aware of the undeniable fact that copper is the greenest of the green metals,” he adds.

“Given the challenges of global environmental priorities, and the trend of urbanisation that emerging economies throughout Africa share with many nations, copper is definitely the most important metal of our time.”

Kamoa-Kakula is unique as it combines ultra-high copper grades in thick, shallow and relatively flat-lying deposits ─ allowing for a large-scale, highly-productive, mechanised underground mining operation.

The ultra-high copper grades and underground mines mean that Kamoa-Kakula will have a small surface footprint and will use a fraction of the power, water and consumables ─ and produce far less tailings ─ than any comparable large, low-grade, open-pit porphyry copper mine currently in operation elsewhere in the world.

Ivanhoe Mines is committed to tailings management that meets or exceeds global best practices for safety during all phases of the mine lifecycle. For example, approximately 55% of the Kakula’s tailings will be mixed with cement and pumped back underground to fill voids and help support the underground mine. The remaining 45% of the tailings will be pumped to a tailings storage facility.

Clean, sustainable hydro-electric power for Kamoa-Kakula

Ivanhoe is also committed to powering its mines with clean, sustainable hydro-electricity. Ongoing upgrading work at the Mwadingusha hydropower plant in the DRC has significantly progressed with major equipment being delivered to site.

The progressive re-commissioning of the turbines, fully refurbished and modernised with state-of-the-art control and instrumentation, is underway and is expected to be completed in Q3, 2020. The refurbished plant is projected to deliver approximately 72 MW of power to the national power grid.

Mine development options at Kamoa North being considered

In February 2020, Ivanhoe Mines issued an updated independently verified indicated mineral resource that increased the combined Kamoa-Kakula project indicated mineral resource to 423 Mt grading 4.68% copper, at a 3% cut-off. At a lower cut-off of 1%, the combined Kamoa-Kakula project indicated mineral resource now stands at 1.4 Bt grading 2.7% copper.

The entire Kamoa deposit was updated in the new mineral resource estimate. The majority of recent drilling, however, targeted the ultra-high-grade Bonanza Zone at Kamoa North, and an approximated north-south corridor of elevated copper grades in the far north of the mining licence area (the Far North Zone).

The new Kamoa mineral resource estimate covers approximately 600 m of strike length in the deeper western portions of the Bonanza Zone (west of the West Scarp Fault), and 1 500 m of strike length in the shallower eastern portions of the Bonanza Zone, defined by drill sections spaced 50 m apart on strike in the central section, and 100 m apart on strike elsewhere.

The new resource estimate includes the initial indicated mineral resource estimate for the Kamoa North Bonanza Zone, which includes 1.5 Mt grading 10.7% copper, at a 5% cut-off. The Bonanza Zone combined with the Kamoa Far North Zone provide an indicated mineral resource of 12 Mt at a copper grade of 4.65%, at a 3% cut-off.

Given the shallow depth, remarkable thickness and massive copper sulphide mineralisation discovered within the Kamoa North Bonanza Zone, Kamoa-Kakula’s engineers are evaluating potential options to accelerate the development of this new discovery.

Geotechnical and hydrogeological drilling to provide support for future mining studies has been completed and mine planning is underway. A number of metallurgical composites also have been generated for existing coarse reject material that will be used for flotation test work.

Drilling continues to target additional resources in the vicinity of the ultra-high-grade Bonanza Zone and the Far North Zone. Several geophysical studies such as ground gravity, ground magnetics and airborne have been conducted in the Kamoa North area to better understand the controls of the ultra-high-grade mineralisation and assist in locating additional targets.