The discovery of vast copper ore deposits in
Bougainville's Crown Prince Range led to the establishment of the copper mine in 1969 by
Bougainville Copper Ltd (BCL), a subsidiary of the Australian company
Conzinc Rio Tinto of Australia. The mine began production in 1972, with the support of the Papua New Guinea National Government as a 20% shareholder. In contrast to this, the Bougainvilleans received 0.5–1.25% share of the total profit. The site was at the time the world's largest open-pit copper/gold mine, generating 12% of PNG's GDP and over 45% of the nation's export revenue. Profits derived from the mine helped fund Papua New Guinea's independence from Australia, in 1975. While operational, the mine produced 3 million tonnes of copper and 9.3 million ounces of gold. Mining at Panguna included the direct discharge of
tailings into tributaries of the
Jaba River. The mine caused devastating
environmental issues on the island, and the company was responsible for poisoning the entire length of the Jaba River, causing birth defects, as well as the extinction of the
flying fox on the island. Bougainville Copper had set up a system of racial segregation on the island, with one set of facilities for white workers and one set for locals. The combination of environmental damage and disproportionate share of profits flowing to PNG, rather than the Bougainvilleans, prompted an uprising in 1988, led by
Francis Ona, a Panguna landowner and commander of the
Bougainville Revolutionary Army (BRA). The outcome of the uprising was the
Bougainville conflict, between the BRA, who sought secession from PNG, and the
Papua New Guinea Defence Force. The ten-year conflict resulted in over 20,000 deaths, the eventual closure of the mine on 15 May 1989, and the complete withdrawal of BCL personnel by 24 March 1990. In June 2016, Rio Tinto relinquished its role by divesting its interests in the mine to national and local governments. , the mine remains closed. ==Environmental impacts==