Mount Carlton underground project advances
Contractor Redpath is expected to start decline development in July or August for a new underground mine at the Evolution Mining operation, 150 km south-east of Townsville.
However, Mt Carlton general manager Anton Kruger said work was already well underway on supporting infrastructure such as pads for equipment, laydown areas, and installation of services including power, water and ventilation required for underground operations.
Key changes to processing plantDesign work is underway for a processing plant modification, expected to be completed by January/February next year.
“We’re not looking to increase throughput – it is more about increasing capacity at the tail end of the plant,” Mr Kruger said.
“The deeper you go, the more sulphide-rich the ore body becomes.
“The Mount Carlton plant is nominally designed for 7-8 per cent flotation mass pull, but changes to the ore characteristics as we go deeper means the mass pull will exceed 12 per cent of the material, therefore we need to increase the capacity of the concentrator at the back end of the plant.”
The new decline will run from the southern wall of the existing open pit mine.
“That will target some ore that is off to the east of the pit, partially under the existing waste dump,” Mr Kruger said.
“That is one of the reasons we have considered going underground, rather than relocating the waste dump.”
The underground development will be mined concurrently with the open-cut operation, but will not boost throughput. Instead it will spin out mine life by two to three years based on the current mine plan.
Underground mine opens up exploration potentialMr Kruger believes there is strong potential to stretch that further as the underground development allows exploration of previously difficult-to-access areas.
“Once development of the underground starts we will be able to get some diamond drilling in and do some further exploration, with potential extension for the underground,” he said.
“I’m convinced there will be more – but it’s nothing at the moment that we can put a number on.”
The Mount Carlton operation has a workforce of about 155 people and that is expected to grow to more than 180 when underground mining begins.
Mr Kruger said the number of workers on site would peak around 200 during the construction period for the underground mine and processing plant expansion.
First ore from the underground mine is planned to be delivered in FY21.