In a recent Cobre Panama project update that coincides with an investor site tour, First Quantum Minerals has provided further detail on the mining technology being used and the fleet that is in place. The project has a strip ratio waste to ore of 1:1, with a 40+ year mine life and M&I Resources of 3,695 Mt at 0.37% Cu and P&P Reserves of 3,182 Mt at 0.38% Cu. The total project capital cost is $6.3 billion and has been 72% completed. It will have an 85 Mt/y throughput, using an in-pit crushing and conveying system of four semi-mobile primary crushing stations and a diesel-electric truck, shovel and large wheel loader fleet. Power is via a dedicated 300 MW power plant.

This year sees the first generation from the power plant, complete pit prestripping – exposing of ore, development of terrace mining, and deployment of the ultraclass fleet as well as commencement of commissioning of the process plant. Next year sees the commencement of ore feed from the mine to process plant and the ramp up of the process plant to annualised 74 Mt/y mill feed with a target of 150,000 t Cu in concentrate production. Finally, 2020 sees the ramp up of the process plant to annualised 85 Mt/y mill feed and a target of 270-300,000 t Cu in concentrate production with the 350,000 t Cu reached in 2021.

In the main Botija pit, 46.5 MBCM material movement was complete end April 2018 out of 68 MBCM total prestrip. Pre-strip progress on track for January 2019 first ore. Electric shovel assembly is underway and the primary crusher boxcuts are well underway. The company gives the mine plan rationale as the use of terrace mining “to manage pit waters and make best use of ultra class mining equipment; maximise electrification with rope shovels, trolley assist with the T 284 fleet and electric drills and IPCC for efficient movement of low grade/high volume ore. The working Botija pit floor will be mined in multiple pit benches (three to four of 50-100 m width) or terraces to allow pit floor flexibility and efficiency. The inter-ramp slope will be 45-60 degrees with typical pushback or phased bench development of 140-180 m width with multiple shovel deployment. Interphase slopes will either be at interramp angle or reduced to 40 degrees to manage spillage.

This is the first time details have been given on the IPCC set-up, which include four box cuts with semi-mobile primary crushers, two per conveyor line, feeding two in-pit conveyor lines feeding two overland conveyors after a transfer station to the secondary crushing and the main process plant. In terms of the open pit fleet, the ultraclass trucks achieved over 1,000 operating hours; OEM support contracts have been finalised; and critical spares identified and held in country; while the site has been transferring and training current pre-strip personnel to the ultra class fleet.

The final fleet details are as follows: four Komatsu Mining P&H 4100XPC electric shovels; 30 363 t Liebherr T 284C trucks, three Komatsu Mining Le Tourneau L2350 large wheel loaders (with SR drive), three Liebherr R 9350 hydraulic excavators and 20 Cat 777G 100 t trucks.