Tag Archives: underground mining

Abra project heads for first lead-silver production in 2023

The Abra base metals project in Western Australia is racing forward to first production in 2023 after the project owners signed off a positive final investment decision (FID) for the mine’s development.

The FID was made following the satisfaction of key conditions to draw in excess of $30 million under a debt facility.

As of May 31, 2021, the project is 17% complete, with completed works including: construction and commissioning of a 280-unit mine site village; mining of the box cut (pictured); box cut ground support works; installation of site communications; and various site clearing, roadworks and civil works.

“As a result, Abra is largely prepared for the deployment of key contractors for the construction of the plant and auxiliary infrastructure, and deployment of the underground mining contractor,” Galena Mining, the 77.28% owner of the project, said.

Among the key contractors at Abra is GR Engineering Services, which is set to deliver a 1.2 Mt/y lead sulphide flotation process plant and ancillary infrastructure under a A$75 million ($58 million) guaranteed maximum price arrangement. The underground mining services contract has been awarded to a tier one Australian mining contractor, Galena said without naming the contract recipient.

“Under the current project schedule, procurement of certain long-lead items will take place immediately,” Galena said. “The underground mining contractor is expected to initiate the portal and decline development in the third (September) quarter of 2021 calendar year and physical on-site plant construction is expected to commence in the fourth (December) quarter of 2021 calendar year.”

Related to the decision to move ahead with development, Galena said it was appointing Anthony James as Managing Director of the company, a mining engineer with senior underground operational and development experience. He will replace current MD Alex Molyneaux who will remain a director of the company.

This definitive feasibility study outlined development of a mine and processing facility with a 16-year life producing a high-value, high-grade lead-silver concentrate containing around 95,000 t/y of lead and 805,000 oz/y of silver after ramp-up.

Bis’ UGM backs up growth plans with new Morisset facility

Australia-based underground services provider, UGM, has opened the doors on its new purpose-built diesel and electrical workshop facility in Morisset, New South Wales.

UGM, which forms part of the Bis group, said the location for the new facility was strategically selected for its proximity to the region’s key mining operators, providing enhanced services for customers.

Building on UGM’s existing underground repair, overhaul, field service and spare parts services, the western Lake Macquarie facility was also designed to support UGM in delivering new services to a broader customer set.

Bis Underground Services General Manager, Mark Doyle, said the move will bolster UGM’s diesel and electrical capacity and provide faster expert service for its underground mining and civil customers.

“The Morisset location provides proximity to local mining operations and the opportunity to design a space with a much larger footprint, to support our growth plans.

“The new facility is three times larger, enabling UGM to offer a broader range of niche customer solutions. One of these is growing our tunnelling infrastructure capabilities, including our licensed Mitsui roadheader operations, which services major civil underground projects throughout the Eastern seaboard.”

SRK reflects on rock-related accidents in South Africa mining industry

Rock-related accidents in South Africa’s mining sector have reduced significantly in recent decades, due in large part to incremental improvements in rock engineering practice, SRK Consulting explains.

According to William Joughin (pictured), Chairman of SRK Consulting and himself a rock engineering expert, the company’s contribution in this field has included assisting mines with reviews of safety practices, as well as providing safe rock engineering designs and detailed seismic hazard analysis.

Fall of ground (FOG) is the leading cause of fatalities in the sector, making up a third of mining fatalities in 2019, according to the Minerals Council South Africa. The organisation has reported recently that total FOG injuries have dropped from 1,121 in 2003 to 379 in 2019, while FOG fatalities are down from 131 to 20 over this period.

Joughin notes, however, that this reduction in the number of injuries and fatalities is also linked to the general decline in mining industry employment. There have been few major technological changes implemented in the last five years, in particular, which could help reduce injuries and fatalities. Instead, the focus has been on behavioural change.

“The industry is focusing its efforts on changing human behaviour, because the exposure of people remains high and workers have to manually implement safety measures,” Joughin said. “These efforts have had mixed results, but there is renewed research and development into mechanisation that could significantly reduce the exposure of workers to the more hazardous aspects of mining.”

Methods of seismic monitoring and hazard analysis continue to be developed as new technologies become available. Within its diverse range of projects conducted for the mining industry, SRK contributes to raising safety levels in South Africa mines in these and other ways, according to SRK Consulting Director and Principal Consultant, Andrew van Zyl.

“We have been involved in the Test Mine project and are currently involved with Mine Health and Safety Council projects on collision control and rock safety,” Van Zyl said. “We are also doing pioneering geotechnical work in both the open pit and underground environment.”

He added that the company’s work on water management and mine closure also contribute indirectly to the general levels of improved safety in mining, as do its contributions to tailings dam management in and around mines.

Barrick to bid goodbye to Hemlo open pit as Barminco ramps up UG activities

Barrick Gold says plans to extend the life of the Hemlo gold mine, in Ontario, Canada, by transitioning it to a modernised Tier Two asset with a purely underground operation are well underway as open-pit mining at the mine starts winding down.

The Hemlo open pit has been mined since 1989 and has produced over 2.8 Moz of gold in the process. It was originally used to produce blasted rock for the backfilling of the mine’s underground stopes but, in 2002, a Cat 777 truck fleet and key personnel were seconded from Barrick’s Nevada mines to establish the pit as a separate division.

In 2013, the David Bell mine closed, leaving the open pit and the Williams underground mine as the chief sources of ore for the mill feed. Over the next six years, the open pit ramped up and became the primary source of ore for Hemlo.

With mining at the open pit scheduled to wind down at the end of this month with less than 200,000 t of ore remaining, a transition plan has been put in place to transfer most of the 70 plus open-pit employees to the current underground contractor, Barminco. The open-pit crew has already worked with the contractor in digging a new portal from within the open pit that will open up new mining fronts in the underground mine, creating more flexibility and allowing the underground to ramp up throughput.

Catherine Raw, Chief Operating Officer for North America, said that by repositioning and expanding Hemlo as an underground operation, it would continue delivering benefits to the community, employees and other stakeholders for years to come.

Barrick Hemlo’s General Manager, Adam Foulstone, thanked the open-pit employees for their years of dedication and hard work.

“It’s been a great run and I am honoured to have worked with such a great team,” he said. “The last years of the mine were very challenging but we completed the work with zero lost time injuries, a testament to the commitment and professionalism of our people.”

The mine held a dedication ceremony on October 5 to unveil the new portal sign honouring long-serving employee, Jim Harasym. Harasym is the Open Pit Manager at the Hemlo mine and was instrumental in the success of the project.

DSI Underground and ABC Canada form underground ventilation JV

DSI Underground has signed a new joint venture agreement with ABC Canada to, the companies say, strengthen the safety level for underground mining and tunnelling.

On September 1, DSI Underground Ventilation Systems was officially launched.

The product portfolio of the new joint venture will include Flexline™ and semi-rigid Hardline™ flexible vents for positive and negative airflow, high-efficiency Toughvent fans, and other ventilation accessories: curtains and coverings, emergency shelters, inflatable airstop and repair kits, the companies said.

In addition, the joint venture will have a team of engineers specialising in the design of ventilation systems, capable of providing advice and the necessary technical support, increasing the level of safety and profitability of the projects by optimising energy. The company is a direct manufacturer of supplies and fabrics, ensuring the products meet the highest technical and quality standards required, they said.

DSI Underground Ventilation Systems will start operations in Santiago, Chile, with a production plant of more than 2,000 sq.m and will be present in the Latin America region, directly through entities in the region and with an exclusive distributor in Colombia.

“We are confident that this new company will allow us to deliver more efficient and comprehensive solutions to our customers and will enable us to continue to reinforce progress in underground mining and tunnelling,” the companies said.

Worley out to help miners on their open pit to underground mining transition

As open-pit mines reach their economic end of life, mine owners are considering the viability of transitioning their open-pit operations to underground.

Drawing on its deep level mining expertise in South Africa, Worley helps mine owners around the world to explore the feasibility of underground life of mine extensions and identify the most efficient and safe underground mining methods.

Among the driving factors in the transition to underground mining are declining ore grades, deeper ore deposits, and an increase in demand for minerals required for the global energy transition, such as copper, lithium, manganese and nickel, Worley says.

“Worley’s centre of excellence for copper in Chile has been supporting open-pit copper mine customers for nearly three decades,” the company said. “The company is gearing up its underground capability as these mines shift their operations to below surface to access deeper ore reserves.”

Going deep in South Africa

Worley’s South Africa operations is one of the company’s mining centres of excellence with niche experience in deep level mining.

Mining has been the mainstay of South Africa’s economy for well over a century, and a major source of employment as well as foreign investment. Consequently, Worley has grown its South Africa mining team in one of the best mining environments in the world, with a collective experience of over 120 years in deep level mining and process expertise.

Robert Hull, Vice President for Mining, Minerals & Metals in Africa, says Worley’s South African operation is recognised for its deep level shaft experience, and the company also has experience across most commodities including base metals, coal, platinum, gold, diamonds and ferrous metals.

Hull says Worley has a strong global workshare philosophy and culture of collaboration. The specialist skills in South Africa gained from working on some of the biggest underground projects in the world are an integral part of Worley’s mining, minerals and metals global project delivery offering.

Deep level mine skills

Some of South Africa’s specialist deep underground skills include shaft design, ventilation and refrigeration shafts, high pressure pumping, and deep level hoisting.

Worley says it is one of the few companies in the world that has the expertise to design hoisting systems for mass hoisting, such as at the Venetia Underground Project, which will hoist approximately 6 Mt/y of rock.

The De Beers Venetia Mine in South Africa is the biggest source of rough diamonds in the country, according to Worley. The mine is in the process of transitioning from open pit to underground, to extend its life by some 25 years.

As engineering procurement and construction management contractor for South Africa’s largest mining execution project, Worley is using 3D designs for the project infrastructure to provide 3D models for the entire project’s surface and underground infrastructure, it said.

Intelligent mines

Hull says Worley is leading the way in developing digital solutions for the planning, design and execution of mining projects, with the South Africa office having played a key role in the design and development of much of the group’s digital technology in mining and minerals processing.

Hull (pictured) cites the Wafi-Golpu (owned by Harmony Gold Mining and Newcrest Mining) feasibility study update, in Papua New Guinea, where the South Africa team drew on SmartPlant design technology, which uses rapid prototyping and Building Information Modelling. The technology allowed the entire project team to visualise project objectives as never before, greatly improving operational efficiency in a dynamic time and cost-saving environment, according to Worley.

The Wafi-Golpu project is ranked as a world-class deposit in terms of its size and the grade of gold and copper within it. If developed, it will be the largest, deepest and most complex underground mine in Papua New Guinea, with a mine life of 28 years, Worley says.

Integrated project delivery teams

Worley’s South Africa team is also supporting its Australia counterparts to project manage the delivery of the deepening and expansion of an underground gold mine. This includes construction of a 1,460 m shaft, additional capacity in the processing plant, and supporting infrastructure to enable profitable recovery of ore at depth to 2 140m below surface. IM understands the project in question is the Newmont-owned Tanami Expansion 2 project, in the Northern Territory of Australia.

Mega machines for mega mines

Hull says every underground project Worley has executed has drawn on the company’s large material handling capabilities.

“In South Africa, we have a dedicated materials handling department that has the latest tools including discrete element modelling and finite element analysis, and advanced simulation tools for conveyer design,” he said.

Coenie Mynhardt, Winder Engineering at Worley, adds that mine payloads have increased dramatically in the last two decades in pursuit of higher productivity rates. Mines such as Impala and Phalaborwa, in South Africa, with an approximate 12-t per skipload, were considered ‘mega mines’ in their day. The mines of the future are more than double that size.

“The mega mines of the future need mega machines to be able to handle such big payloads,” Mynhardt says. “Materials handling technology for such deep, high tonnage operations will test current technology for capacity and reliability to bring the ore from the production levels to surface. We have the skills and expertise to find the solutions to these challenges.”

Global project delivery

“Countries such as Chile have immense potential for transitioning from open pit to underground if the geology supports it,” commented Hull. “With the wealth of experience across locations and over 4,000 staff in our mining, minerals and metals business line, we can safely and successfully deliver our customers’ underground mine assets through collaborative development of the mine and associated infrastructure anywhere in the world.”

Caason Group and LDO Group to explore next gen underground mining tech developments

Caason Group says it and LDO Group are to explore next-generation technology to improve underground mining operations with a renewed commercial relationship.

LDO, based in New South Wales, Australia, is a mining industry innovator and tunnelling expert, according to Caason. It is has been the exclusive distributor of Canada-made Rokion battery-powered vehicles in Australasia since 2018, having recently helped introduce a Rokion R400 to the BHP Mitsubishi Alliance Broadmeadow mine, in the Bowen Basin.

“LDO also specialises in systems, processes, mine planning and training, which is aligned with Caason Group’s HardRock Coal Mining interests (mining lease in Tasmania),” Caason Group said.

HardRock Coal Mining Pty Ltd, established in 2011 by Caason Group, is set to become Tasmania’s premier coal exporter, Caason says. It currently leases a 27,000 ha site in the Fingal Valley from the Tasmanian Government. At full production, the mine will deliver an initial 1 Mt/y of export quality thermal coal, according to the company.

Oyu Tolgoi loses some of its underground reserves following updated feasibility study

An updated feasibility study on the development of the underground mine at Oyu Tolgoi, in Mongolia, has confirmed that the huge copper-gold project will be delivering sustainable production later than initially planned and this output will come with a higher capital expenditure bill.

Majority owned by Rio Tinto through its 66% stake in Turquoise Hill Resources, Oyu Tolgoi is currently being mined as an open-pit operation (producing 146,346 t of copper and 241,840 oz of gold in 2019), yet previous studies have indicated a combined open-pit and underground operation could up the tally to around 500,000 t/y of copper.

Back in July 2019, Rio Tinto included an update on the underground project saying first output was expected to be achieved between May 2022 and June 2023, a delay of 16 to 30 months compared with the original feasibility study guidance in 2016, while preliminary estimates for development capital spend was $6.5-$7.2 billion, $1.2-$1.9 billion up on the $5.3 billion previously disclosed.

The updated feasibility study issued this week from Oyu Tolgoi LLC (owned 66% by Turquoise Hill and 34% by the Mongolian government), which is in the process of being submitting to the Government of Mongolia in accordance with Mongolian regulations and standards that require mining companies to submit updated feasibility studies every five years, includes a delay of 21 to 29 months for first sustainable production compared to the original feasibility study guidance in 2016 and an increase of $1.3-$1.8 billion from the original $5.3 billion development capital.

This process has also seen 1.22 Mt of copper, 850,000 oz of gold and 7.01 Moz of silver removed from the Hugo Dummett North reserve base compared with the December 31, 2019 calculation, with some 80,000 t of copper, 70,000 oz of gold and 550,000 oz of silver added to the Hugo Dummett North Extension reserve base.

It also includes a new mine design for Panel 0 of the Hugo Dummett North underground mine at Oyu Tolgoi, as well as confirming that the caving method of mining remains valid.

Detailed study, design, engineering and optimisation work is ongoing to support the definitive estimate of Panel 0 for the development of this orebody, which remains due in the second half of 2020, Rio said.

These estimates are subject to any additional scheduling delays or increases in capital costs arising from the impacts of the ongoing COVID-19 pandemic, it added.

Back in July 2019, Rio said enhanced geotechnical and geological information obtained from drilling and mapping at depth suggested there may be some stability risks associated with the original mine design. This updated design was the result of a review of this information.

The updated design retains two in-situ rock pillars on either side of Panel 0 for geotechnical stability, whereas the original mine design had these pillars within the mining area. “The updated design is supported by extensive geotechnical modelling and industry leading technical assurance,” Rio said.

As a consequence of leaving the pillars in place, the material contained in the pillars has been reclassified from reserves to resources, Rio said, adding that part of the material contained in these pillars could be recoverable at a later stage following additional studies currently underway. This saw 2.43 Mt of copper, 570,000 oz of gold and 4.81 Moz of silver added to the July 3, 2020, Hugo Dummett North resource base.

Ore handling infrastructure will be relocated to the pillars, located immediately north and south of the current Panel 0 boundaries, Rio explained, with Panels 1 and 2 now be initiated as independent panels or mine blocks.

Optimisation of mine designs for Panels 1 and 2 is ongoing and it is anticipated that this next phase of study may result in further movements in classifications of reserves and resources, according to Rio.

Arnaud Soirat, Chief Executive of Copper & Diamonds, said: “This amended mine design is another positive step in the development of the underground mine which will unlock the most valuable part of Oyu Tolgoi. We remain focused on delivering the underground project safely and within the guidance ranges we have announced on both cost and schedule.”

RCT goes to new heights for Western Australia underground mining clients

Autonomous solutions specialist RCT says it has fulfilled requests from mining clients and devised a unique warning system designed to prevent oversized equipment from getting stuck inside underground mining portals.

Staff from RCT’s branch in Kalgoorlie, Western Australia, were separately approached by two major mining clients in the Goldfields region and asked to devise a solution to prevent portal blockages, which can severely disrupt regular mining operations.

Branch technicians subsequently produced the Over Height Portal Warning System, which consists of a laser mounted at a particular height connected to a unit placed at the portal entrance.

The unit, designed and built in RCT’s workshop in Kalgoorlie, will produce an audible alarm and flash the word ‘STOP’ to alert machine operators and nearby site personnel there is a potential over-height hazard.

Site personnel are able to determine the system’s field of view and isolate areas such as a corner or pole so that the system will only activate when it senses new objects, according to the company.

RCT Kalgoorlie Branch Manager, Rick Radcliffe, said: “Occasionally underground haul trucks try to re-enter the portal with their trays accidentally in a raised position and this causes the trucks to get wedged in the portal.

“The time needed to dislodge the haul truck from the portal is very costly to the mining operation. Therefore, the Over Height Portal Warning System is a cost effective and easy solution that will help keep mining operations running smoothly.”

Since its development, the Over Height Portal Warning System has been sold to 10 mine sites throughout the Goldfields region, RCT says.

Epiroc slims Sweden workforce following COVID-19 related demand drop

Epiroc has provided a notice of termination to 425 employees in Sweden as it looks to adapt to the changing COVID-19 demand situation in the mining and infrastructure sectors.

The move is in response to lower global demand from these sectors amid the pandemic, and to position the company better for the future, it said.

Some 350 positions are expected to go at the company’s Örebro facilities, with 75 positions being removed in Fagersta, Sweden, of which half are positions in production, the company said.

Örebro is a main manufacturing and research and development hub for Epiroc’s underground and surface equipment as well as for service and spare parts supply, while Fagersta is home to Epiroc’s rock drilling tools business. Epiroc has about 3,100 employees in Sweden, out of a global workforce of some 14,000.

Epiroc said: “The action is the result of Epiroc facing a significant drop in demand from customers due to the COVID-19 pandemic’s effects on the global economy. The work reductions are also part of Epiroc’s continuous effort to become as agile and efficient as possible and follows various efficiency measures taken worldwide since 2019.”

The company, in April, announced it would consolidate the manufacturing of exploration drilling tools in Canada, gradually moving its base from North Bay to Montreal and Sweden over the course of 2020, with around 65 employees in North Bay, Ontario, being affected.

Helena Hedblom, Epiroc’s President and CEO, said: “We are taking these actions to adapt to the new market situation following the COVID-19 pandemic and to make us stronger and more resilient for the future. Unfortunately, we must take such a drastic action as giving notice of termination. We regret the negative consequences this will have for our colleagues and those close to them, and we will support our employees in this difficult situation.

“These actions will allow us to continue to prioritise innovation and to develop our technology leadership in order to support our customers’ operations and improve their productivity.”

Epiroc’s innovation investments have led to the mining and infrastructure industries becoming more productive, safe and climate friendly, according to the company, following the adoption of its automation, digitalisation and electrification solutions.