 The Koolan Island mine closed in 1994 after BHP had extracted 68 million tonnes of high-grade haematite ore, averaging 67% iron.At its peak, Koolan Island had a population of 950 people and had a school, police station, recreation facilities and shops.It had the world's then-longest golf course hole — an 860 yards par 7 number 6 which doubled as the island's air strip.