Located about 570 kilometres north of Adelaide, South Australia, Olympic Dam is a multi-mineral ore body. It is the world's fourth-largest remaining copper deposit and the largest uranium deposit. It also contains significant quantities of gold and silver. Olympic Dam is Australia's largest underground mine.

The ore body was first discovered by WMC Resources in 1975 and production commenced in 1988. In August 2005 the mining operation was acquired by BHP Billiton.

The Olympic Dam mine is unique because the complete process, from mining the ore, processing, smelting and refining to final product, occurs on-site.

The majority of Olympic Dam's employees live in Roxby Downs, located 16 km south of the mine. The township has a current population of about 4,200.

What is being proposed?

BHP Billiton is proposing to expand its mining and processing from around 200,000 tonnes per year of copper to approximately 500,000 tonnes per year. This involves a number of development options, including mining and processing methods, water and energy supply options and transport and infrastructure requirements.