BHP Billiton and Codeleo have decided to advance their bioleaching joint venture to the next stage. This will involve the construction of a pilot plant capable of producing 20,000 t/y of copper cathode. The construction of the plant will cost US$60 million and is scheduled to reach full capacity by the end of 2003. It will be located at the Chuquicamata mine in northern Chile. The 50:50 venture, known as Alliance Copper Ltd, was founded to commercialise bioleaching for the production of copper from low-grade copper sulphide ores. Alliance Copper has the global rights to the BioCop^® process developed by Billiton (prior to its merger with BHP).

Both companies believe that the technology has significant potential to transform many of the world's SX/EW copper mines, where suitable reserves of oxide ore are running low. They envisage that bioleaching could be used to recover copper and existing SX/EW plants could be used to produce copper cathode.