The Quebrada Blanca orebody is a porphyry copper deposit located in a 30-40 kilometre wide belt of volcanic and sedimentary rocks which contains a number of the world’s largest copper mines including Collahuasi (10 kilometres to the east) and Chuquicamata (190 kilometres to the south). All of these deposits are spatially related to a major north-south fault, the West Fissure Fault, or to splays off this fault.

The Quebrada Blanca orebody occurs within a 2 kilometre by 5 kilometre quartz monzonite intrusive stock. Supergene enrichment processes have dissolved and redeposited primary (hypogene) chalcopyrite as a blanket of supergene copper sulphides, the most important being chalcocite and covellite, with lesser copper oxides/silicates such as chrysocolla in the oxide zone. Irregular transition zones, with (locally) faulted contacts separate the higher and lower grade supergene/dump leach ores from the leached cap and hypogene zones.

Production has recently declined, and Teck expects the existing leachable supergene mineralization to be mined-out by 2017–2018.

In early 2017, Teck completed an updated feasibility study on our Quebrada Blanca Phase 2 project. The proposed Quebrada Blanca Phase 2 would extend the life of the existing mine as a large scale concentrate producing operation.

Mining operations will continue to use open pit methods, and conventional truck-and shovel operations. From an operational standpoint, QB2 represents a continuation of the existing supergene mine activities; however, there are significant differences between the two operations, such as the significant increase in the ultimate pit depth and width, the change in rock type from enriched supergene to hypogene, and increases the mining extraction rate.

The conventional open pit supergene mining operation is expected to exhaust the remaining supergene ore in the open pit in late 2017 to early 2018 (leaching operations will continue while economically viable), at which time active mining operations in the area of the open pit will cease until the hypogene mining commences in 2021. The existing QB1 mining fleet will be used in pre-production and early works activities related to QB2, including the mass excavation required for the concentrator site, and mass earthworks associated with construction of the starter dam for the TMF.

QB2 has a 25-year mine life, nominally from 2021 to 2046 and minor pre-stripping requirements.

Quebrada Blanca is an open-pit mine which produces ore for both heap leach and lower grade dump leach production. Copper-bearing solutions are collected from the heap and dump leach pads for processing in an SX-EW plant which produces copper cathode. Copper cathode is trucked to Iquique for shipment to purchasers.

Ore is delivered from the pit to a primary crusher, crushed and then discharged by conveyor belt to a coarse ore stockpile. Ore is drawn from the coarse ore stockpile by conveyor belts feeding a vibrating screen with oversize in turn passing through a secondary standard cone crusher. The product is then conveyed to five surge bins, which feed five tertiary screens. The oversize product is passed through five tertiary crushers. Ore is received at the agglomeration drum from a conveyor belt discharging into a fine ore bin. Ore passes through one of two agglomeration drums. Agglomerated ore is transported by a system of overland conveyors, tripper, and grasshopper conveyors to a stacker in which ore is placed on the dynamic leach pads in 8 m high layers.

The heap leach is augmented by a run-of-mine dump leach.

Sulphuric acid leaching of ore is accomplished with a system of drip emitters placed on top of the leach pads. The pregnant leach solution (PLS) exiting the leach pads is stored in a pond prior to being sent to the SX/EW plant.

The PLS is mixed with organic and diluent to capture the copper and increase the concentration. The organic is stripped with spent electrolyte. Raffinate is sent to a raffinate storage pond to be recycled in the heap leaching process together with the dump leach PLS. The tank house consists of 264 cells containing 1 m2 stainless steel cathodes. Cathodes are harvested 24 hours a day and are 100% LME grade A quality.