The George Fisher expansion involves the development of a second hoisting shaft and associated infrastructure to service the northern area of the mine. Large-diameter raise boring technology will be used to develop the shaft. An underground crushing and ore handling facility will be installed underground, and power and air ventilation services will be upgraded. An existing shaft servicing the northern end of the mine will be lined and extended by 420 m to a depth of 1,140 m.

Xstrata Zinc Australia COO Brian Hearne said the expansion project was encouraged by a 126% increase in zinc reserves from 33 million mt when Xstrata acquired the operation in 2003 to 76 million mt this year. “While the increased production rate will reduce the life of the mine by five years to 21 years, the orebody remains open at depth to the north of the mine,” Hearne said. “The additional production capacity built into the expansion project and our ongoing exploration program will ensure that the George Fisher mine remains a key part of our long-term strategy for Mount Isa.”

The George Fisher expansion follows initiation of a project to deepen the Black Star open cut at Mount Isa, announced in late March 2010, and brings the total value of new mining projects at Mount Isa announced by Xstrata Zinc this year to A$407 million. Both projects ensure the full utilization of Mount Isa’s zinc-lead concentrator capacity, which was raised to 8 million mt/y in 2009.