Capstone Mining Corporation added another 219 million pounds of copper to its measured and indicated resources at Minto mine this week.
This new metal will be needed, because, as of mid-April, Minto’s main pit is mined out.
Enough ore has been stockpiled for the mine to keep churning out concentrate until the end of 2011. Then Capstone will need to start extracting ore from elsewhere on the property.
Thankfully, the company has made eight discoveries over the past four years at Minto. And, as the company continues to drill, it’s beginning to look as if several strikes along a 3.5-kilometre stretch south of the main pit are connected.
The newly announced metal is located along this ground, which has been consolidated under the new title of Minto South.
Loaders and dumptrucks are already digging a new pit, where mining is to commerce in early 2012. What’s more, the company also plans to burrow underground.
At Minto South, there’s rich copper near the surface, then more rich copper deep in the earth. Sandwiched between this rich rock is low-quality ore.
The company considered digging one big, open-pit mine. But it reckoned that digging underground would lessen the environmental impact – and make more money.
“If you go underground, you can skip all the marginal material – we can get the high grade from the open pit and the high grade from the underground, all at the same time,” said Darren Pylot, Capstone’s president and CEO.
Minto’s mine life is currently estimated to last until 2020. But this target continues to roll back as new discoveries are made. When the mine opened in 2007, it only had a three-year lifespan.
The mine currently employs 300 workers. It mills between 3,000 to 3,500 tonnes of ore each day.
Capstone expects Minto to churn out between 39 to 41 million pounds of copper in 2011.
The company plans to spend $5.2 million on its exploration program at Minto in 2011. It has two drill rigs on site and plans to bring a third in, with the goal of drilling 33,750 metres of core samples. Capstone will release updated resources this autumn.
The company already has a new quartz mining licence for its new operations at Minto South. It plans to request an amended water license later this summer.
With Minto’s main pit now empty, Capstone plans to put half of it to work as a new storage facility for waste rock, with the other half set aside to store excess storm water.
The company was condemned by First Nations and conservationists in the autumn of 2009, when Minto dumped more than one million cubic metres of wastewater into the Yukon River, after the mine was deluged by a particularly wet spring runoff. A similar emergency discharge was released the previous year.
Pylot describes those years as “two 100-year water events in a row. They aren’t supposed to happen in 100 years, but we had two.”
This year would have been far more convenient. In 2009, Capstone was forced to flood its main pit to hold its surplus of wastewater. In doing so, it had to halt mining.
Now, with the main pit empty, Minto has surplus storage space. “But, as luck would have it, we’ve had no issues with water.”
In January, Capstone fully repaid the $17.4 million it owed Yukon Energy for connecting Minto mine to the grid, seven years ahead of schedule.
Not long ago, Minto was the only operating hardrock mine in the territory. Now it’s joined by Alexco’s Bellekeno mine and Yukon Zinc Corporation’s Wolverine mine, which are both expected to hit full steam later this year.
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