Canadian Mining Journal


The HudBay Way

A severe drought may have plagued much of the prairies this past summer but the shortage of rain did little to dampen the excitement at HudBay Minerals as the company celebrated important milestones at three of its projects in Northern Manitoba.

A severe drought may have plagued much of the prairies this past summer but the shortage of rain did little to dampen the excitement at HudBay Minerals as the company celebrated important milestones at three of its projects in Northern Manitoba.

Thanks to continued development at its Lalor, 777 North, and Reed Copper sites; three mining projects strung along the 55th parallel like pearls on a string, Hudbay has enjoyed one of its busier times since the company first broke ground in the area almost 100 years ago.

Historically, Hudbay was one of the pioneers of Northern Manitoba mining and its Flin Flon zinc and copper discovery in 1915 turned out to be one of the largest industrial development projects in the Western Hemisphere; second only to the Panama Canal in terms of scale at the time.

The Flin Flon claim, named by founding prospector Tom Creighton and near where the three properties are now located, is almost 500 kilometres northwest of Winnipeg, right on the Manitoba/Saskatchewan border. It’s known as the Flin Flon Greenstone Belt (FFGB) in the Canadian Shield, one of the world’s largest exposed areas of Precambrian rocks.

The ore bodies, where Hudbay has called home for almost a century now, stretch for an exposed length of 250 kilometres east-west and 75 kilometres north-south and contain an estimated 60 million tonnes of zinc and copper as well as vast deposits of gold and silver.

It’s one of Canada’s richer and older mining areas and thanks in most part to HudBay Minerals, and with permitting support from the Manitoba government, it’s also being recognized around the world as a very inviting and accessible region to work in, both in terms of infrastructure and from a workforce perspective.

Hudbay’s relations with its neighbours and governments are “excellent,” and that’s one of the reasons company President and Chief Executive Officer David Garofalo says they have been so successful for so many years in Northern Manitoba.

“Our very first mine gave rise to the Town of Flin Flon, and we are still there today, running a world-class operation and pursuing opportunities in step with the community,” says Garofalo. “Over the course of our history, Hudbay has proven to be a responsible business and a responsible corporate citizen; upholding a strong set of values and ethical principles.

“We believe that hiring as many local people as possible is best for Hudbay and for our communities. In 2011, we worked to prepare residents living near our Lalor, 777 North, and Reed Copper projects for employment at these operations. We value our longstanding associations with the communities near these operations and our experience in Flin Flon has demonstrated the importance of affiliations with our neighbours.

Garofalo says that one of the company’s prouder achievements was donating land and financially supporting the construction of the Northern Manitoba Mining Academy, which he says is designed to train the next generation of area miners for high-skilled, and high-paying jobs.

Hudbay’s Lalor, 777 North, and Reed Copper properties certainly present opportunities for local workers but more than that, they are also an inspiration to Canadian mining in general because they demonstrate that there’s a ‘next generation’ of mines being developed out there too.

When Hudbay closed its Flin Flon mine in 1992 after 62 years of operation, there was a sense of abandonment that accompanies every community when a mine closes, but as alluded to earlier, Hudbay wasn’t about to give up its roots in Northern Manitoba and in 1993, the company announced that it had discovered a substantial ore body while conducting underground exploration drilling at the site of what would eventually become the company’s flagship 777 Mine.

To the delight of the miners from Flin Flon, the new 777 Mine site was close by and a project renewed faith in mining for the future of the region.

In traditional Hudbay fashion, the company never gave up on expanding and developing its resources in Northern Manitoba and today, work at the 777 North Mine Project involves driving a ramp from surface to the 440 metre level to access 777 North Zone ore and East Zone 9 ore. This resource of 551,272 tonnes grading 1.0% copper and 3.65% zinc is part of the overall 777 mineable resource.

All of the North Zone work is independent of Hudbay’s original 777 Mine, but is expected to add up to 330 tonnes per day to the operation when it goes into production in early 2013. Before that, however, a surface ramp connecting 777 North with 777 is being built to allow the operation to move equipment in and out of the mine for equipment rebuilds or new purchases.

Ramp access will be the second means of egress replacing a manway to surface as well as creating further exploration opportunities by creating new drill platforms. This portion of the 777 North project started on October 12, 2010, and the location of the portal was positioned so that the mine could benefit from a retired smelter infrastructure such as air, water and power.

Break through from 777 North to 777 is expected for late 2014 or early 2015. It’s a big job requiring a fleet of Atlas Copco jumbos, CAT scoops, and once in production, Hudbay will use Sandvik 400 tonne trucks to haul material to the surface.

Farther along the 55th parallel and centred about 100 kilometres either way from Hudbay’s 777 operations and its Lalor Mine, is the Reed Copper project where Hudbay (70%) has a joint venture agreement with VMS Ventures Inc. (30%) to develop a property containing a resource of 2,550,000 tonnes grading 4.52% copper and 0.91% zinc.

Because of the geography of the area and the limestone cover, McCaw North and Golder Associates were hired by the joint venture to grout a curtain around the portal and ventilation raise areas and because the ore body is very close to surface, it will be accessed by a 5.5m x 4.7m ramp.

The ore body is three stacked tabular zones of mineralization beginning at 25m and extending to 580m below surface. A longhole mining method is being used with Atlas Copco M2D jumbo rigs and a fleet of 40/50 tonne Sandvik trucks handling the hauling.

Production at the Reed Copper project is expected to reach 1,300 tonnes per day by the end of 2013 and the mine is expected have a life of about five years.

At the other end of the “mine-life” scale, the Lalor Mine is expected to keep customers and management smiling for the next 20 years because of its large VMS resource of more than 30 million tonnes of zinc, copper, gold and silver.

Lalor’s Project Manager Kim Proctor told Canadian Mining Journal that the Lalor deposit was discovered in 2007 and “In five very quick years, I’m proud to say that in August of this year, we mined the first ore from the Lalor deposit.

“Since the first hole intersected the base metal lens back in 2007, the Lalor site has been buzzing with excitement because of the prospects found from that original Deep Penetrating Electromagnetic Survey. The ore body is flat lying with dips ranging from 15 to 35 degrees in a easterly direction with thickness ranging from three to 17 metres.

“The deposit has multiple stacked lens currently identified as six base metal lens, five gold-bearing lens, and one copper/gold lens. The ore body starts at 570 metres below surface and extends down to 1,500 metres and is open down plunge. The lateral extent is 1,000 metres in the north-south direction and 750 metres east-west.”

Clearly, Hudbay’s Lalor deposit had plenty to offer and the company wasted little time, nor money, in going after its new-found treasure. In fact, there were three stages of capital expenditure:

Stage 1 – Approval of $85 million to ramp from the existing and neighbouring Chisel North ramp system over the Lalor deposit, then to proceed with metallurgical testing and build surface site infrastructure.

Stage 2 – Approval in total $
560 million funding necessary to fast track the development of the mine.

Stage 3 – Incremental approval of $144 million to build a new concentrator located on the site for a total capital investment of $704 million.

Here’s a closer and more technically detailed look by Proctor at what’s happening at the Lalor mine site.

“As briefly mentioned earlier, a 3.2-km ramp was driven from the 410 metre level on the Chisel North ramp to the 810 metre level near the base metal lens Number 10 at the Lalor deposit. This ramp was started in December 2009 and completed late 2011. Work was completed by J.S. Redpath.

“The main ventilation shaft at Lalor is a 6.1 meter circular opening, sunk to the 850 metre level, supported by rebar and screen. The shaft is now connected with the ramp development allowing for through ventilation. There is also a temporary loading pocket which allows for up to 1,500 tpd to be hoisted up the ventilation shaft over the period while the development of the Main production shaft is completed.”

At ground level, surface infrastructure includes a new hoist house with two Davy Markham hoists with ABB drives systems. The headframe design and shaft construction will follow the same design as the 777 Mine that Hudbay operates in Flin Flon , Manitoba. The engineering design work was completed by Stantec who also did the engineering design for the 777 Mine.

The main production shaft is currently being sunk by Dumas and is roughly 30% completed, the planned depth of the shaft is 985 meters. The shaft is a circular 6.7 meter monolithic lined, five compartment shaft designed to hoist 6,000 tpd and is planned to be available in late 2014.

Hudbay mining crews are starting to transition over to the Lalor deposit as the Chisel North reserves will be exhausted this year. They are using new Altlas Copco jumbo’s M2D’S along with a fleet of 60 tonne trucks and a scooptram fleet of 1520’s. The underground roof support is a screen with resin rebar using a fleet of MacLean bolters

The underground mine plan will consist of a combination of Cut and Fill, Post Pillar and Longhole Stoping. The dips as well as the ore widths will dictate the mining methods used. Paste backfill will be available once the new concentrator is built. The early ore from Lalor will be milled in Snow Lake at the Stall Lake Concentrator, with recovery of copper and zinc concentrates.

Collection of drill core samples for an extensive metallurgical testwork program began in 2008. Testwork was done by SGS Vancouver and included mineralogical analysis, hardness testing, gravity concentration, copper, lead and zinc flotation, and extraction of gold from flotation tailings. Starkey and Associates were hired to do SAG design testwork and the design of the grinding circuit.

The initial plan was that Lalor ore would be processed at the existing Snow Lake Concentrator, with process upgrades and refurbishments to the plant as necessary. However, as the project evolved it became apparent that a new concentrator would provide significant advantages, including increased production rates, elimination of the 15 kilometre ore haul, and the opportunity to produce paste backfill for use as ground support in the mine. A trade off study was initiated in 2010, and SNC was hired to provide preliminary costs for comparison of the two concentrator options.

This trade off study showed that the new concentrator had the potential to be the best option, and the project was advanced to a prefeasibility study. This phase of work was awarded to Amec, and the study was completed in August 2011.

The capital cost estimate from the study included $263 million for the base metals concentrator. The decision was made to proceed immediately with the base metals plant, and defer the gold plant until further exploration and testwork could be done. Amec was contracted for the basic engineering and procurement phase of the project.

The design capacity of the concentrator is 4,500 tonnes of ore per day. The flowsheet includes a single stage of jaw crushing, a SAG and ball mill grinding circuit, a regrind in the copper circuit, sequential flotation of copper and zinc concentrates, and production of paste backfill for the mine.

Copper concentrate will be pressure filtered and trucked to Flin Flon for shipment to smelters. Zinc concentrate will be vacuum filtered and trucked to the zinc plant in Flin Flon for refining.

Procurement of equipment is well underway with orders placed for the crusher and mills. Bids are under evaluation for the other major packages including the flotation cells, process control system and dewatering equipment. The jaw crusher selected was a Telsmith Model 3858 with hydraulic chamber clearing. The SAG mill and ball mill package was awarded to Metso. The SAG mill size is 6.7 m diameter by 3.12 m, and the ball mill size is 4.57 m diameter by 8.23 m. Both mills are powered by identical 2500 kw ABB induction motors and drives. An M1000 IsaMill was purchased from Xstrata Technology for the copper concentrate regrind duty.

The basic engingeering phase of work will be complete this fall, with detailed engineering expected to follow immediately after. The application for the Environment Act License is also nearing completion with submission expected this fall. Construction of the concentrator will start upon successful regulatory approval, currently estimated to be in Q2 2013.

The construction period is estimated to be 18 months, with commissioning of the concentrator expected in Q4 2014. When in full production, the concentrator will operate 362 days per year and will employ approximately 70 people.

Clearly, HudBay Minerals is committed to its Manitoba operations and its three current projects; Lalor, 777 North, and Reed Copper are prime examples of why “The HudBay Way” is the right way to do business.

“Over the past year we celebrated milestones at three mines, which collectively represent more than $800 million dollars of growth investments in northern Manitoba. Our Lalor mine in Snow Lake marked first ore production and will help perpetuate our operating legacy in northern Manitoba beyond the 100-year mark. Our Reed Copper Project celebrated a ground breaking with construction of its portal underway. At our 777 North expansion in Flin Flon, we marked the production of first ore and progress on its development. The progress we have made at these three sites is not only a testament to the skill of our workers but it also demonstrates that Manitoba is one of the best mining jurisdictions in the world.”

David Garofalo.