Following the completion of the pre-feasibility study (PFS) in 2015, CAML made the decision to undertake a DFS on its 75% owned Copper Bay tailings project in the Atacama Region of northern Chile. Copper Bay Limited effectively holds the exploitation licence comprising 15.25km2.
The project is a site of historic tailings disposal on the beach at Chañaral Bay. This resulted from the Potrerillos and El Salvador copper mines releasing tailings residues from their respective mineral processing operations into the Rio Salado, which outflows into Chañaral Bay. Between 1938 and 1975, it is believed that some 250 million tonnes of tailings were discharged and now sit in the beach, surf and bay zones.
The DFS utilises a dredging operation to recover the copper tailings, a solvent extraction and electro-winning (SX-EW) plant to produce copper cathode and a flotation circuit to produce a copper in concentrate product that could be marketed to nearby smelters.
The study envisages a nine year project, comprising two years of construction followed by seven years of operation, which would process five million tonnes of material annually at a copper grade of 0.24%. Total copper recoveries in the processing plant are expected to be 72%, yielding an annual average of 7,080 tonnes of copper cathode and 1,560 tonnes of copper in a concentrate grading 20%.
The feasibility study was undertaken by Copper Bay with detailed input from the following international consultants:
Cube Consulting Pty Ltd, Australia – geology, resources, mineable resources, engineering and financial analysis
IHC BV Mining Advisory Services, The Netherlands – dredge study and mine design