Triple Play

There are only a handful of mines in Ontario with a history as deep and rich as Goldcorp’s Red Lake Gold Mines, located about 350 km northwest of Thunder Bay, near the Ontario/Manitoba border.

Originally developed in the 1940s, the mines, comprised of the Red Lake Mine, bought by Goldcorp from Dickenson Mines in 1994, and the Campbell Mine, purchased from Placer Dome in 2006, combined to produce some of the highest grades of gold found anywhere in the world.

In fact, they were once known as “the world’s richest gold mines,” and to this day, those two mines have produced more than 27 million ounces of gold. But, like all “maturing” mines after decades in production, resources were gradually depleting and that’s exactly what was happening at the Red Lake Gold Camp a few years ago.

Faced with this reality, but also knowing that the mines were still located in one of the richest gold-bearing deposits on the planet, Goldcorp decided to stick with it and dig deeper, both figuratively and financially, to get at the new levels of gold they knew were still there.

The challenge, however, was that the “new” gold was quite a bit deeper, and to go after it would require a great deal more than simply drilling downwards. It would involve advanced mine engineering, particularly in the areas of de-stressing and mining methods.

In typical Goldcorp fashion, the company held nothing back when it came to knowing exactly what it was going after and what potential risks existed. An extensive geological study and a $30-million drilling program confirmed “lots of potential,” and that’s all the company needed to know in order to get the wheels in motion.

Because of the proximity of the Red Lake

and Campbell Mines to one another, geologists were able to trace a gold-bearing corridor between the two mines and determine they are inter-connected by a drift at depth.

That depth, however, was 2500 metres. Depth at the Red Lake Mine is 1,820 m while the Campbell shaft reaches 1,315 m, so, obviously, the miners had some work ahead of them.

In addition to the challenge of extending the depth of the shafts, engineers also faced the ground “stresses” mentioned earlier as well as the associated risks of working deep beneath the surface; namely heat and a supply of air.

As mining eventually reaches the 2500 m level and possibly more, working conditions will get increasingly warmer and proper ventilation will become paramount to the operation.

To ensure safety, Goldcorp engineers have designed a system whereby intake air is pushed down the shafts, through older workings, to cool in the summer and be pulled out through five exhaust raises. Air going down the shafts is also heated in the winter to prevent freezing of the shaft infrastructure.

Underground work at both the Red Lake and Campbell mines is extensive and ongoing, but Goldcorp is also excited by, and is now actively pursuing, new deposits found beneath the historic Cochenour mine; located just 7.5 km from Goldcorp’s gold-rich Red Lake Camp property.

The Cochenour Mine dates back to 1939 and was once one of the more active mines in Ontario until it closed its doors in 1971. It remained closed until 2008 when Goldcorp took over, and since then work has been moving at a fevered pitch to bring that mine back into production by the fourth quarter in 2014.

In less than two years from now, Goldcorp expects to restore the Cochenour mine’s status, and put the Town of Cochenour (which sits on top of the mine), back on the map.

The mine is scheduled to produce between 250,000 and 275,000 ounces of gold annually.

It’s a $420-million project that will give the mine a 20-year mine life, and as mentioned earlier, Goldcorp is not shying away from anything and is going flat out right now to make the Red Lake Gold Camp one of the more outstanding gold properties in the province, if not the world.

Understandably, much development work has to be done, and that’s where crews from J.D. Redpath Limited, Mining Contractors and Engineers of North Bay, have played a leading role in making the mine safe and nearly ready for production once again.

Rolf Arnold, Redpath’s Area Manager for the Red Lake region, said: “Starting in 2009, we dewatered and rehabbed the old shaft. On the 2050 level, we also rehabbed that level by installing power and driving a track drift.”

As mentioned earlier, the Cochenour mine is reasonably close to the main Red Lake Camp (particularly the Campbell Mine) and Arnold explained: “One of our main projects is to drive a drift from the Campbell Mine to the Cochenour shaft. This is about 21,000 feet in length and measures 14 feet wide by 16 feet high.”

“Our cycle is to muck, shotcrete, rebar, screen, prep the face, and drill around and load with emulsion,” said Arnold. “The area is then cleared and the round is blasted. We have just installed 6,500 feet of track and Phase Two is now underway. All material is now moved by train to the transition area. We will go 6,500 feet ahead and install track again… then the final stretch to the drift.”

Arnold said there is also a Redpath crew building the new muck car repair shop. They are pouring floors, installing overhead cranes, and installing charging stations for the locomotives.

Work at the Cochenour site continued during construction of the drift, and in 2010 crews took down the existing headframe, and a concrete structure (complete with steel) was completed in Spring of 2011.

“All hoists were installed and made operational and we concurrently slashed out the shaft for 200 feet and installed the Galloway for sinking. In December (2011), we started to slash the shaft and poured the concrete lining to a finished diameter of 18 feet, said Arnold.

The shaft is now (January 2012) in full sinking mode at 2,750 feet in depth.

“We will slash the shaft, rehab stations until we hit shaft bottom, then we will sink full face to 4,250 feet and cut shaft stations,” said Arnold.

Redpath crews are also driving a number of raises for production purposes. There are presently 3 Mechanized Raise Climber (MRC) units on site, and once the raises are complete, crews screen the raise and cut sub drifts at designated elevations.

“We are driving the track drifts with muck machines and long toms. Some crews are rehabbing abandoned areas that are being started again due to the price of gold,” said Arnold.

Gold prices and a renewed interest in one of Ontario’s more famous mining districts have certainly restored faith in the residents of the Town of Cochenour, but moreover, it’s also put smiles on the faces of the 230 crew members working to bring the Cochenour mine back into production.