PERTH (miningweekly.com) – Diversified miner Glencore would ramp up copper production from its Ernest Henry mine, in Queensland, from three-million tonnes a year to six-million tonnes a year, by 2015, after transitioning to an underground operation.

Metal production would also double to 50 000 t of copper and 70 000 oz of gold in concentrate over the extended mine life, to 2026.

The miner on Wednesday celebrated the culmination of its A$589-million investment into the Ernest Henry mine, starting operations from a new kilometre-deep hoisting shaft.

COO for copper assets in North Queensland,  Mike  Westerman, said Ernest Henry’s development strengthened the production profile and sustainability of Glencore’s regional copper operations.

“Our assets in Mount Isa and at Ernest Henry accounted for around 14% of Glencore’s global copper production in 2013. This investment in Ernest Henry has effectively added 14 years to the life of the mine to 2026.

“We’re pleased to have this opportunity to sustain production at a higher rate, continue to support around 500 employees plus contractors and deliver ongoing benefits to the Cloncurry community and economy.”

Queensland Minister for Natural Resources and Mines Andrew Cripps has welcomed the extension of the Ernest Henry mine, saying it would boost the state’s economy.

“The Newman government promised at the 2012 election to grow resources as one of the four pillars of the economy. We are delivering by cutting red tape and speeding up approvals to restore the sector as a world leader,” Cripps said

“Mining is now a larger employer of full-time workers in the state than both the agricultural or hospitality sectors, which highlights the importance of the sector to Queensland families as well as economic growth.”

The underground project started in December 2009 and has involved more than 50 km of underground development accessed by a 6 km decline, the construction of associated infrastructure, including the underground primary crusher and 1.2 km of below the surface and overland conveyors to transport ore to and from the hoisting system, and the installation of a 75-m-high permanent headframe to house the hoisting system and with a capacity to lift around 1 000 t/h.

As at December 2013, Ernest Henry had total ore reserves underground of 74-million tonnes at 1.04% copper and 0.53 g/t gold.