Newcrest Mining reported in late October that its Cadia East panel cave mine in New South Wales had reached a major milestone with the safe propagation of Panel Cave 1 through to surface, significantly ahead of expectations. The propagation connects the broken rock of the cave to the surface, reducing production risk and increasing draw flexibility. The breakthrough means production becomes less constrained, providing more flexible ore extraction.
Cadia East is part of Newcrest’s Cadia Valley Operations, located approximately 25 km from the city of Orange in central-west New South Wales and 250 km west of Sydney. The Cadia East panel cave mine began commercial production on January 1, 2013. Cadia East development is now focused on the propagation of Panel Cave 2, which began commercial production on October 1, and the connection of the two caves.
Cadia Valley Operations also include the Ridgeway underground mine. Cadia East and Ridgeway feed a 26-million-metric-ton-per-year (mt/y) processing plant that produces both a gold-rich copper concentrate and gold doré recovered from a gravity circuit. Production for the year ended June 30, was 592,831 oz of gold and 60,612 mt of copper.
Newcrest Managing Director and Chief Executive Sandeep Biswas said, “Newcrest has developed world-class expertise in bulk underground mining techniques gained from the establishment of the Ridgway sublevel cave and block cave and the Telfer sublevel cave. This experience has led to the successful achievement of this critical milestone of the Cadia East project ahead of time.”
As of year-end 2013, Cadia Valley’s estimated mineral resources contained 47 million oz of gold and 8.9 million mt of copper, including reserves estimated at 28 million oz of gold and 5.1 million mt of copper.
In other news from Newcrest, the company reported that work at the Wafi-Golpu gold-copper project in Morobe province, Papua New Guinea is continuing to evaluate underground access and reduced capital expenditure options. An updated pre-feasibility study is scheduled for completion by the end of December. The project is a 50:50 joint venture between Newcrest and Harmony Gold.