Tag Archives: Redpath

Redpath continues mechanised sinking evolution with S20+ deployment at Odyssey

Redpath is continuing its focus on mechanised shaft sinking operations, with the latest example being the planned use of the hydraulic shaft mucker S20+ at the Canadian Malartic Partnership’s (CMP) Odyssey gold project in Quebec, Canada.

Redpath Canada was recently contracted by the CMP to sink a 6.5-m diameter, 1,800-m deep concrete lined shaft at Odyssey, a project that has the potential to become one of Canada’s largest and most technologically advanced underground gold mines.

CMP, which is 50:50 owned by Yamana Gold Inc and Agnico Eagle Ltd, previously laid out plans to extract 19,000 t of ore at an estimated grade of about 2.75 g/t gold and roughly 5,000 t/d of waste rock during peak operations at Odyssey. The ore will be processed at the operation’s existing plant, which will eventually be adapted to the future mine’s needs including shifting from 57,000 t/d to 20,000 t/d. The ore will be hauled to surface using Blair production hoists with use of both shaft bottom and mid-shaft ore handling systems.

The sinking concept at Odyssey includes the use of the S20+, which was built by Redpath Deilmann in Germany. A previous iteration of this machine, the S20, was used with success on four shaft projects in both soft rock – with an integrated tool package – and hard rock.

The S20+ offers similar capacity/productivity to a North American pneumatic telescopic boom mucker but with a much easier learning curve for operators, according to Kevin Melong, Vice President – Shafts and Technical Services, at Redpath Canada.

Unlike the RD S100, which can move independently of the galloway within the shaft via a telescopic boom, the S20+ is connected to the galloway, requiring the lowering of the galloway to move the mucker into position for mucking.

Melong added: “The S20+ does present some potential for concurrent mucking when in and around the shaft station construction/excavation, but, in general, does not act independent of the stage as in the S100 design.”

Fitted with a bucket as standard, the S20+ offers a maximum digging depth of 7.96 m and a bucket volume of 560 litres. It also offers good flexibility, with the bucket capable of six rotations per minute.

Alongside the S20+ and the aforementioned S100, Redpath has been mechanising the shaft sinking process in mining through the use of large-diameter raiseboring equipment and operation of Herrenknecht’s Shaft Boring Roadheader (in soft-to-medium rock). The company is also working with Herrenknecht on the development of the Shaft Boring Cutterhead, a machine developed for medium-to-hard rock applications up to 250 MPa UCS.

South32 making engineering and design headway at Hermosa project

A stellar set of annual financial results has provided the ideal backdrop for South32 to update shareholders on its rapidly progressing Hermosa project in Arizona, USA.

Released late last month, the company’s 2022 financial year results showed off record earnings of $2.6 billion, record free cash flow from operations of $2.6 billion and record return on invested capital of 30.1%.

With group copper-equivalent production expected to increase by 14% in the next financial year, South32 looked to be well leveraged to in-demand metal markets at the right time.

The company has progressively been repositioning its portfolio toward metals critical for a low-carbon future, having already established a pipeline of high-quality development options. One of these high-quality development options is Hermosa.

Hermosa, which the company acquired outright back in 2018 as part of a takeover of Arizona Mining, is key to the company’s critical metals pursuit, having exposure to base and battery metals that are expected to grow in demand – both domestically in the US and internationally.

It is being designed as South32’s first ‘next generation mine’, according to Hermosa President, Pat Risner, with a series of technical reports highlighting its use of automation and technology to minimise its impact on the environment and target a carbon-neutral mining scenario in support of the group’s goal of achieving net zero operational greenhouse gas emissions by 2050.

These same reports also highlighted the potential to develop a sustainable, low-cost operation producing zinc, lead and silver from the Taylor deposit, with the bonus of possible battery-grade manganese output for rapidly growing domestic markets from the Clark deposit.

In the latest results, the company said it was devoting $290 million of growth capital expenditure in the 2023 financial year to progressing Hermosa as it invests in infrastructure to support critical path dewatering and progress study work for the Taylor Deposit. This is ahead of a planned final investment decision expected in mid-2023, which should coincide with the feasibility study.

South32 is devoting $290 million of growth capital expenditure in the 2023 financial year to progress Hermosa

Some $110 million of this was assigned to construction of a second water treatment plant (WTP2) to support orebody dewatering at the asset, alongside dewatering wells, piping systems and dewatering power infrastructure.

An additional $95 million was slated for engineering and initial construction ahead of shaft sinking at the operation, plus work to support power infrastructure and road construction.

The remaining amount was expected to support work across the broader Hermosa project, including Clark study costs and the Taylor feasibility study.

All signs from these results are that the company is laying the groundwork to develop this project ahead of that mid-2023 deadline.

In another sign of progress, South32 recently signed a “limited notice to proceed” for shaft engineering and design at Hermosa with contractor Redpath, Risner confirmed, adding that the award represented a positive step forward for the project.

“We look forward to continuing our engagement with local communities and all of our stakeholders as we make further progress with the project,” he said.

Redpath will no doubt be evaluating the technical studies that have been signed off to this point and informing future reports.

The PFS design for Taylor is a dual shaft mine which prioritises early access to higher grade mineralisation, supporting zinc-equivalent average grades of approximately 12% in the first five years of the mine plan. The proposed mining method, longhole open stoping, is similar to that used at Cannington, in Australia, and maximises productivity and enables a single stage ramp-up to the miner’s preferred development scenario of up to 4.3 Mt/y.

Yet, the Clark deposit opportunity – which has become even more tantalising with the US Government invoking the Defense Production Act and supporting the production of critical metals including manganese – could see the plan change.

The company says it may accelerate the prefeasibility study for the Clark deposit, which is spatially linked to the Taylor deposit. A scoping study has previously confirmed the potential for a separate, integrated underground mining operation producing battery-grade manganese, as well as zinc and silver from the deposit.

South32 previously said Clark has the potential to underpin a second development stage at Hermosa, with future studies to consider the opportunity to integrate its development with Taylor, potentially unlocking further operating and capital efficiencies.

With a PFS selection study expected later this year, investors and interested parties will soon know the role Clark could play in the wider Hermosa project.

What is easy to gauge already is that Hermosa is progressing on a track that many other development projects in in-demand sectors have gone down.

Redpath Australia wins cut and flit contract at Whitehaven’s Narrabri operations

Redpath Australia says it has been awarded the Cut and Flit Development Contract for Whitehaven Coal at its Narrabri operations in New South Wales, Australia.

Situated around 28 km southeast of Narrabri on the North West Slopes in New South Wales, the Narrabri operations mine site is one of Australia’s most productive underground coal mines. Whitehaven is the majority owner – with a 77.5% interest – and the operation has approval to extract up to 11 Mt/y of coal from the longwall operations.

Mark Donghi, General Manager – Mechanical Excavation for Redpath, says the project will employ around 55 personnel and the aim is to start recruiting immediately.

Redpath Australia’s Managing Director, Gavin Ramage, said the company is looking forward to working closely with Narrabri operations in delivering the project safely and efficiently.

The company said: “As a market leader in providing advanced development solutions to mine owners across Australia and around the globe, Redpath is well placed to deliver this project for Narrabri Coal Operations.”

PT Freeport Indonesia, Redpath achieve drawbell milestone at Grasberg Block Cave

Freeport Indonesia’s (PTFI) Grasberg Block Cave (GBC) operations in Indonesia, together with strong Redpath support, have successfully attained the milestone of constructing and blasting the 300th drawbell.

The milestone, which occurred on June 30, 2021, came in a record time of only 2.5 years from the production start date, according to Redpath.

The same production crews also surpassed the 100,000 t/d mark, by reaching a record of 107,000 t/d on June 26, 2021. This record surpassed the previous site record of 101,000 t/d.

In Redpath’s Advance magazine, I Made Pasek, General Superintendent, GBC Operations, said COVID-19 had not prevented the GBC project from becoming the world’s largest block cave mine.

“In addition to delivering safe and effective development meters, the GBC1 development team has reached the significant milestone of completing the excavation of the GVD 9 Fan Chamber (Grasberg Ventilation Decline), the fifth such chamber of the GBC ventilation system,” Pasek said when reviewing progress during the June quarter. Each of these chambers is equipped with a 5,500 kW fan able to produce 1.7 million cu.ft (48,139 cu.m) of air per minute.

The underground production levels of the GBC mine requires not two, but three crusher chambers to be excavated and constructed to deliver the targeted quantity of 160,000 t/d of ore. PT Redpath Indonesia’s GBC 2 crew are leading with the development of the #603 crusher chamber while concurrently initiating access to the #604 conveyor drives, according to Pasek.

GBC’s construction, MRC and MCM teams were challenged with the realignment of a key section of rail installation for the #602 unloading arrival station during the June quarter. This particular section of rail needed to be disassembled and raised in order to enable ore trains of 11 rail cars to enter the #602 unloading station as per design.

“Working seamlessly with the client’s engineering, planning and rail teams, the undertaking was safely and effectively accomplished ahead of schedule,” Pasek said. “The work itself consisted of drilling 1,000-plus holes for track support, epoxying track bolts into the existing concrete base, followed by meticulous forming works under each track base plate. The work required a high level of accuracy with tight tolerances to ensure rail alignment and smooth travel, in order to meet the established productivity rates.”

Pasek added: “These significant achievements would not be possible without a strong and deeply rooted safety culture in the GBC operations, paving the way for even greater successes in the future.”

Sandvik delivers 100th automated loader in APAC region

Sandvik Mining and Rock Solutions says it has delivered its 100th loader connected to the AutoMine® platform in the Asia Pacific region.

A Sandvik LH621i loader was delivered to Byrnecut Australia in March, making it Sandvik’s 100th automated load and haul unit to be delivered in APAC.

Sandvik has 30 AutoMine systems installed across Australia, Papua New Guinea and the Philippines, with customers including Barminco, OceanaGold, Redpath, and Byrnecut, who now have 11 sites in Australia connected to AutoMine. The first AutoMine system in the region was delivered and commissioned in 2008 for Mount Isa Copper Operations, now owned by Glencore.

AutoMine is Sandvik’s automation system for autonomous and tele-remote operation for a wide range of Sandvik and non-Sandvik underground and surface equipment. It provides a safe and controlled process to increase mine productivity and profitability, as well as protect operators and other mine personnel in underground and surface operations.

AutoMine can be scaled from tele-remote or autonomous operation of a single machine to multi-machine control and full fleet automation with automatic mission and traffic control capability. Operators can simultaneously control or monitor multiple machines from the comfort and safety of a remote control room, Sandvik says.

Sandvik recently demonstrated this capability with the successful trial remote operation of a LH621i loader at OZ Minerals’ Prominent Hill mine in South Australia. The LH621i was successfully operated from the Remote Operating Centre in OZ Mineral’s Adelaide office, taking OZ Minerals a step closer to realising its goal of remote operations from home.

“The digitalisation field has developed significantly over the years and we have adapted to meet the industry needs along the way,” Sandvik Mining and Rock Solutions Technical Support Manager – Mine Automation, Ty Osborne, said.

“We have seen our customers change their mindset from ‘this technology is nice but won’t work in our mine’, to, ‘what do have to do to make this work in our mine?’. Our customers are now seeing the value of including digitalisation in their mine planning and recognise the tangible benefits an automated fleet can bring to their operation.”

Redpath to deliver Pumpkin Hollow ramp-up, Nevada Copper says

Nevada Copper has engaged mining contractor Redpath USA to implement its ramp-up strategy for its underground copper mine at Pumpkin Hollow, in Nevada.

The company commenced production at the underground mine in December and is now entering into a new phase of development supporting its ongoing operations. It said it has “high confidence” in Redpath’s ability as a partner during the ramp-up to full commercial production in 2020.

Redpath replaces the previous mining contractor and will be the company’s principal underground mining contractor going forward, Nevada Copper said. “Redpath is a highly experienced mining contractor with experience of delivering complex projects both internationally and in Nevada, ahead of schedule and under budget,” it added.

Matt Gili, Chief Executive Officer of Nevada Copper, said: “Nevada Copper made the transition to producer in Q4 (December quarter) 2019 and we have developed a clear, straightforward strategy for ramping up our Pumpkin Hollow underground project to full commercial production. Redpath is considered throughout the mining industry as the partner of choice for production ramp up and we are excited to be working with them during this important period of growth.”

Nevada Copper has previously said it is focused on ramping up the mine, in Yerington, to reach nameplate capacity in the first half of 2020.

The 2017 prefeasibility study plan for the underground mine outlined a 5,000 t/d project able to produce some 50 MIb/y (22,680 t/y) of copper, 8,000 oz of gold and 150,000 oz of silver over a 13.5-year life at all-in sustaining costs of $1.96/Ib of copper. It also laid the foundations for a larger integrated project that includes open-pit development and could increase throughput to 70,000 t/d.

Glencore, Redpath and Sandvik in it for the long haul at Lady Loretta

Automation and equipment monitoring are helping Redpath Australia exceed expectations at Glencore’s restarted Lady Loretta zinc mine, according to a Sandvik Solid Ground story.

Glencore awarded Redpath Australia the Lady Loretta zinc mine contract in December 2017, encompassing the entire underground and surface operations and associated facilities management.

Redpath’s responsibilities at one of the world’s highest-grade zinc operations range from crushing the ore it extracts and loading it onto road trains for haulage to Glencore’s processing facility in Mount Isa, Queensland, to managing the camp and keeping lawns manicured, Sandvik said.

“Redpath also holds full statutory responsibility for the operation, a unique role for a contractor typically tasked with driving a decline or undertaking development and production,” Sandvik said.

John McKinstry, Redpath’s Operations Manager for Lady Loretta, said: “Operating a mine is an exciting proposition for Redpath. A normal contractor scope is to put down a heading or undertake a specific task, but we have a much broader scope here. The infrastructure’s already in place, so it’s quite a different role for a contractor. Being a life-of-mine contract is unusual in itself. Most mines evolve as you develop and find more ore, but this orebody is very well-defined.”

Redpath recommissioned the mine within months of winning the contract, firing the first development round in March 2018. Production ramped up quickly and, by July 2018, Redpath was meeting Glencore’s production and development targets. Monthly production grew to 100,000 t, with a full production capacity targeting 133,000 t/mth.

The contract length enabled Redpath to invest in a brand-new fleet for Lady Loretta, according to Sandvik.
McKinstry said: “We wanted to meet or exceed targets right from the start, so we brought in new, cutting-edge technology to minimise operating costs and maximise productivity, knowing that we’ve got a good life to work the equipment over and amortise assets.”

Two Sandvik DD421 jumbos with 10/16 split feeds have outperformed since commissioning, according to the mining equipment maker. Redpath has consistently achieved 400 m/mth of development using one Sandvik DD421, with the second serving as a backup and handling any rehabilitation work.

Ore is removed by a fleet of four Sandvik LH621 LHDs. Two are operated conventionally for development, manual production and truck loading while the other two are equipped with AutoMine Lite for remote operation.

“The 621, I think, in a lot of people’s eyes at the moment is probably the loader to be using in the bigger operations,” McKinstry said. “It’s a big machine. It’s a very productive machine, very comfortable machine for operators, and then having the AutoMine on top of that just means it really sells itself in many ways.”

Redpath’s motivation for implementing automated loading was simple: regain the productivity lost during each shift change, Sandvik said.

McKinstry said: “There’s a long period of time from when a blast occurs to when you can re-enter the mine. If we can operate those machines from the surface over shift change, we can pick up up to a couple of hours a day in productivity. The other thing about AutoMine is that it does the same thing time and time and time again without banging the walls. It really does just run the perfect line each time.”

Redpath runs three levels at any one time, optimising the loading process.

The connectivity provided by a Wi-Fi network underground has not only enabled Redpath to implement the automated loading from the surface, the contractor can also monitor and manage its fleet in real time through My Sandvik Productivity, the cloud-based version of OptiMine Monitoring, Sandvik said.

“OptiMine has been synonymous with equipment monitoring in the Australian mining industry since its first installation in 2014,” Sandvik said. “My Sandvik Productivity mobile fleet monitoring allows Redpath to keep tabs on equipment condition online and act more quickly to remedy any issues that arise.”

The solution provides detailed, readily analysed data. Each connected LHD collects data onboard and uploads it when it comes within range of a Wi-Fi antenna. The data can be accessed from any computer or tablet, according to Sandvik.

The condition monitoring helps Redpath’s Lady Loretta maintenance staff improve its predictive maintenance planning. My Sandvik Productivity also identifies trending behaviours that can damage equipment or shorten component life, revealing training opportunities, Sandvik said.

Lady Loretta Maintenance Manager, Shane Timothy, said: “When it brings up log codes and faults and alarms, it actually tells you what that means. So you can hover across your icons, for instance, where it says that there’s a brake fault, and it would tell you that your operator is perhaps pressing the brake and accelerator pedal at the same time, which isn’t something that we want them to be doing unless they’re going at a very low ground speed.”

McKinstry believes having better-informed operators who understand their equipment and its limitations will reduce downtime: “We hope that by giving operators the feedback that they’ll change their behaviour in their operation of the machines. And, if we can address it early, then I believe we’re going to get better availability out of this equipment.”

Harte Gold to go commercial at Sugar Zone mine in Ontario

Harte Gold has been given the go ahead by the government of Ontario to start commercial production at its Sugar Zone mine, paving the way for full-scale output of 1,400 t/d in 2021.

This approval means the company is fully permitted to mine, process ore and pour gold on site at Sugar Zone.

Even though Harte has only just received provincial signoff for Sugar Zone’s commercial plan, it has been busy on site where it has already completed a 70,000 t advanced bulk sample, mined 30,000 t of ore under a Phase 1 Commercial Production permit and built an 800 t/d processing plant.

With this permit ticked off, the company can now proceed with its commercial production plan. This envisages a start-up of operations at 540 t/d at Sugar Zone, increasing to 800 t/d in the December quarter of 2019 and, subsequently, to 1,400 t/d from January 2021.

A preliminary economic assessment envisaged the total upfront capital cost at C$58 million ($45 million) and production, from 2019, of 80,700 oz/y at an all-in sustaining cost of $708/oz over an 11-year mine life.

This would see 904,000 oz of total recovered gold production over the mine life, approximately two thirds of the combined indicated and inferred resources announced back in February, Harte noted in the PEA.

In the latest press release, Harte Gold said full commissioning of the mill complex was nearing completion, while testing of the crushing and conveyance system was complete. Water had been successfully circulated through the mill and the power line to site was built, with all electrical equipment delivered and installed.

Underground development work, meanwhile, continues to exceed targeted rates, Harte said.

“For the month of July, 254 m of development was completed, or 8.2 m/d. Development completed to-date has opened up several areas in the Sugar Zone deposit, particularly in the near-surface Upper Zone area, to provide early high-grade stopes,” the company said. Redpath Canada is helping the company out with underground development.

The February resource statement showed indicated resources of 714,200 oz of contained gold averaging 8.52 g/t and 760,800 oz of inferred resources grading 6.59 g/t.