11. Normally, underground mining is between five and 10 times more expensive than open cut mining . 12. The Tarrawonga open cut mine commenced production in 2006. 13. Eventually the open cut mines won out and Black Flag was drastically de-stocked in 1989. 14. Exploratory boring started in 1941 and plans were made to develop the first open cut mine . 15. The Canyon ( formerly Whitehaven ) open cut mine is located 15 km east of Boggabri. 16. In 1984, 13 underground and eight open cut mines were in operation in the Ipswich region. 17. In 1987 Carpentaria Gold Ltd opened a new open cut mine using modern heap leaching processes. 18. Its assets include the plant's adjacent brown coal open cut mine and some 30 years of reserves. 19. The typical nickel laterite mine often operates as either an open cut mine or a strip mine. 20. It is an open cut mine producing a thermal coal that is low in nitrogen and sulphur.
