PERTH (miningweekly.com) – ASX-listed Carbine Resources has been awarded a A$1.25-million-a-year water treatment contract from the Queensland government, covering the Mount Morgan mine.

The Queensland state government said Carbine would use specialist technology to boost environmental management and flood protection and save more than A$150 000 a year.

“This delivers a great package of benefits for central Queensland and the ongoing management of the mine’s environmental issues,” Minister for State Development and Natural Resources and Mines Dr Anthony Lynham said.

“Carbine’s specialist water treatment expertise will mean better environmental outcomes, with more water from the pit decontaminated, without using fresh water.

“Carbine is also looking into using cutting edge technology to extract gold, copper and pyrite resources from the tailings stockpiles, and copper from the pit water, giving a piece of Queensland mining history a new opportunity to be a mineral producer,” Lynham said.

The former Mount Morgan mine operated from 1882 until 1990, producing copper and gold. The Queensland government took over management of the historic mine site in 1991, including the former opencut pit and its 12 000 Mℓ of contaminated water.

A lime-dosing water treatment plant has been operating on site since 2008 and is used to remove metal contaminants and neutralise acid levels, before treated pit water is allowed to enter the Dee river.

Lynham said Carbine would use water polishing technology to treat up to 500 Mℓ of mine pit water over 12 months, at least three times what the existing treatment plant achieved in 2014/15.

“Carbine will boost the existing plant’s capacity with specialist technology that will mean fresh water won’t be needed any more to operate the plant,” he said.

“If we don’t need to store fresh water in dams on site to operate the plant, this means more capacity to cope with heavy rainfall without run-off. Better water treatment will also drop the water level in the mine pit, which, in turn, reduces the risk of contaminated pit water overflowing into the Dee river, as it did in 2013.”

Carbine was planning to submit a proposal to retrofit the existing water treatment plant with an ion exchange demonstration plant at the front end, which would target delivery of multiple additional benefits to the operation, including further improvement to the discharged water quality, extraction of up to 300 t/y of copper from the Mount Morgan water pit and providing a demonstration-scale facility to showcase the use of ion exchange technology for future tailings processing activities.