Underground Large poly-metallic deposit of iron oxide-copper-uranium-gold mineralisation.

The Olympic Dam ore body begins about 300 metres below the surface and continues to a depth of more than 1 kilometre. The existing mining operation employs a sub-level open stope method of underground mining. The underground operation includes crushing stations, vertical ventilation shafts and an automated rail network, used to produce and transport crushed ore to the surface, where conveyors move the ore to the processing plant.

Olympic Dam’s processing plant consists of two grinding circuits in which high-quality copper concentrate is extracted from sulphide ore through a flotation extraction process. The operation includes a fully integrated metallurgical complex with a grinding and concentrating circuit, a hydrometallurgical plant incorporating solvent extraction circuits for copper and uranium, a copper smelter, a copper refinery and a recovery circuit for precious metals. The on-site metallurgical processing plant has an annual production rate of 10 million tonnes.

When the ore reaches the processing plant, it is sent to a concentrator, where it is milled, and a slurry formed by adding water is passed through a series of flotation stages to separate the minerals, producing a copper-rich concentrate and uranium-rich tailings.

The concentrate is leached in acid to remove residual uranium and to produce a neutral slurry, which is dried before being fed into the smelter to produce copper ........