Ivanhoe Mines Co-Chairs Robert Friedland and Yufeng “Miles” Sun today announced a major milestone in the development of the tier one Kamoa-Kakula copper project in the Democratic Republic of Congo (DRC), with the initial joining of the main northern and southern access tunnels at the Kakula mine ─ the first of multiple, high grade, underground copper mines to be developed on the project’s 400-square-kilometre mining licence.
The Kamoa-Kakula project is a joint venture between Ivanhoe Mines (39.6%), Zijin Mining Group (39.6%), Crystal River Global Ltd (0.8%) and the Government of the Democratic Republic of Congo (20%). The subsidiary mine operator is Kamoa Copper SA and the mining contractor is Jimond Mining Management Company, part of China’s JCHX Mining Management.
The Kakula mine is being developed on the eastern portion of the Kakula deposit ─ representing less than half of the overall 13.3 km deposit. The main access tunnels between the northern and southern declines at the Kakula mine were connected in the high-grade core of the deposit, where the average grade is projected to exceed 8% copper.
This week’s holing has opened up the first two high grade, drift-and-fill mining blocks totalling 10.6 Mt at an average grade of 6.78% copper (5.7 Mt @ 7.04% copper and 4.9 Mt @ 6.48% copper) near the centre of the deposit.
“Now that we have initiated development of Kakula’s first two high-grade ore blocks, it is important to note that these two areas alone contain more than 700,000 t of in-situ copper, and approximately 600,000 t of recoverable copper,” said Friedland. “With copper trading at approximately $7,000 a tonne, the saleable value of the copper concentrate produced from these initial two blocks exceeds the estimated capital cost to develop both the first and second phases of production at Kamoa-Kakula. This is the true definition of a tier one mine.”
The Kakula mine is expected to have a mine life of approximately 21 years, while the western portion of the Kakula deposit – Kakula West – is scheduled to be Kamoa-Kakula’s third underground mine to be developed and have a mine life of approximately 16 years.
“The holing is a major achievement and milestone for the project team and our underground mining crews. It opens up the mine’s footprint for ventilation and, more importantly, marks our entry into high-grade ore from both sides of the deposit,” said Mark Farren, Kamoa Copper’s CEO. “We have moved quickly to open up these high-grade reserves at the core of the Kakula deposit. We now will complete the ledging work and prepare the drift-and-fill mining areas for production so that we can feed the concentrator plant with high-grade ore directly from underground when the plant starts operations in July 2021.”
“The holing was spot on and we are very pleased with the result. Ventilation has always been a key factor in determining how many underground mining crews can work at the same time. Air now is flowing freely between the northern and southern declines – a distance of more than 4 km – allowing us to add additional mining crews in the high-grade drift-and-fill blocks as we require them. Each block in the central portions contains up to 7 Mt of high-grade ore,” Farren added.
Underground development from the southern decline was performed by mining crews from JMMC, the DRC subsidiary of leading Chinese mining contractor JCHX, while development from the northern decline was performed by Kamoa Copper’s mining crews.
Second holing expected by June 2021, opening up 26 Mt of ore to feed the initial 3.8 Mt/y concentrator plant. The second set of connection drives is expected to hole by June 2021, opening up an additional high-grade and medium-grade mining block. The width of the initial planned mining blocks of the Kakula orebody measures 1,475 m, of which 880 m is in the +5% and +8% copper grade contours.
Phase 1 copper concentrate production from the Kakula mine is scheduled to begin in July 2021. Kakula is projected to be the world’s highest-grade major copper mine, with an initial mining rate of 3.8 Mt/y at an estimated average feed grade of more than 6.0% copper over the first five years of operation.
The mining method for the Kakula deposit primarily is drift-and-fill using paste backfill; with the exception of a room-and-pillar area close to the northern declines, which will be mined in the early years of production. The paste backfill system will utilise a CITIC Construction supplied paste plant located on surface connected to a distribution system that includes a surface pipe network connected to bore holes located at each connection drive on the northern side of the orebody. Approximately 99% of the deposit will be mined using drift-and-fill, which was chosen to maximise the extraction of high-grade Kakula ore.