Tag Archives: Appian Capital Advisory LLP

Appian Capital to take on Rosh Pinah zinc-lead mine in Namibia

Appian Capital Advisory LLP, the investment advisor to long-term value-focused private capital funds that invest in mining and mining-related companies, has acquired an 89.96% interest in the producing Rosh Pinah zinc mine, in the Kharas region in southern Namibia, from Trevali Mining Corporation.

Rosh Pinah is an operating underground zinc-lead mine with a 2,000 t/d milling operation, which has plans in place – via the Rosh Pinah 2.0 mine expansion project – to nearly double the mine’s annual ore throughput to 1.3 Mt and improve safety and environmental performance. The mine has been in continuous operation since 1969, producing zinc and lead sulphide concentrates, as well as smaller amounts of copper, silver and gold.

Appian says it will retain the existing site management team and workforce, who have substantive technical expertise and understanding of the asset.

Michael W Scherb, founder and CEO of Appian, said: “This acquisition marks a significant milestone for Appian as we continue to develop our world-class portfolio of highly attractive zinc assets, a critical metal that will help facilitate the upcoming energy transition. We look forward to welcoming the 450 employees at Rosh Pinah to Appian as we utilise our extensive operational and project development expertise to support the existing management team with delivering the Rosh Pinah 2.0 expansion project. We extend our gratitude to the Namibian government, our valued partners, and the local community for their trust and support.”

The Rosh Pinah 2.0 expansion project envisages the construction of new processing facilities, including the addition of a paste fill and water treatment plant, as well as a dedicated portal and decline to extended deposits. The project will increase mill throughput from 700,000 t/y to 1.3 Mt/y, increasing zinc equivalent production to 170 MIb/y (31,751 t/y), on average.

Trevali, the former 89.96% owner of Rosh Pinah, said previously that the expansion could also lead to the introduction of battery-electric vehicles at the mine.

Rosh Pinah is one of three recent investments by Appian in the zinc market, with the other two being Vedra Metals in Italy and Pine Point in Canada. It did not disclose the acquisition price for the stake in Rosh Pinah.

Appian continues to flex ‘multi-faceted’ skillset in latest mining deals

Private equity firms might not be the most obvious port of call for companies in need of the technical skillsets to transition ‘projects’ to ‘mines’, but, in recent years, Appian Capital Advisory LLP has shown the industry that it has all the credentials to help with this transition.

The firm, headquartered in London but calling on expertise from across the globe, has just completed divestments of the Santa Rita nickel mine and the Serrote copper mine, both in Brazil.

Sibanye-Stillwater, the purchaser, agreed to pay Appian $1 billion, plus a 5% net smelter return (NSR) royalty over potential future underground production at Santa Rita, for the assets, with the private equity firm, in the process, pocketing a pretty profit.

In 2018, Appian acquired Atlantic Nickel (owner of Santa Rita) out of bankruptcy for $68 million and Mineração Vale Verde, the owner of Serrote, for $40 million.

It reoriented the former large-scale open-pit mine into a much more conservative – and profitable – mine able to produce around 20,000-25,000 t/y of contained nickel sulphide equivalent. It also carried out extensive drilling to showcase its underground potential, prolonging its mine life.

The plans at Serrote, meanwhile, were re-evaluated in a DFS. Having completed project construction and commissioning ahead of schedule and under budget, the mine is now ramping up to nameplate capacity of 20,000 t/y of copper equivalent.

These two divestments represent the fourth and fifth portfolio sales the company completed this year. The others included the sale of its 13.2% interest in West Africa-focused gold company Roxgold to Fortuna Silver Mines, the sale of its 0.28% NSR royalty over the large-scale Caserones copper mine in Chile and the repayment of a royalty Appian held over Peak Resources’ Ngualla rare earth project in Tanzania.

The diversity of these asset exits is indicative of how well-versed mining-focused Appian is in the sector’s ‘hot commodities’, but there is more to appreciate here than purely financial gains and well-timed acquisitions and divestments.

“People know that not all money is created equal,” Michael W Scherb, Founder and CEO of Appian (pictured), told IM. “We have a team that is able to solve specific operational challenges – we can call on specialists to solve problems on the process flowsheet side, for instance – while providing financial advice to avoid expensive streams and set assets up for profitability.”

Scherb’s words are backed up by a solid track record: seven of nine investments it has made have resulted in mine builds. Its divestments have also provided healthy returns.

The company has been able to do this by recruiting industry specialists – mining and finance – and educating them on the facets they need to succeed in both the private equity and mining world.

“People that join Appian need to be multi-faceted,” Scherb said. “We get mining folks to think like investors and vice versa,” he said.

This has seen them build a project review team populated with former consultants and an operations team full of mine personnel with operational experience.

“We then get all personnel to cross-train across these teams to avoid any siloed disciplines,” Scherb explained.

Take Santa Rita as an example of where this expertise paid off.

The company carried out a six-month due diligence process on Santa Rita, which led to the development of a more defensive and low-cost mine plan able to see the asset through nickel price peaks and troughs – in stark contrast to the plan former operator Mirabela Nickel had for the asset.

Among the operating changes implemented were the use of a smaller, locally procured equipment fleet of 40 t trucks (Santa Rita previously used Caterpillar 777 90 t and 785 137 t payload trucks), the use of shorter benches and tighter blasting patterns.

This resulted in better grade and fragmentation control, improving the feed to the crusher.

It also defined a significant underground resource base at the mine, which it will still be leveraged to thanks to the NSR royalty.

Such moves were based on exploiting the nickel sulphides at Santa Rita. This reoriented focus aligned with the industry preference for nickel tied to the battery materials space, which eventually paid off with the amount of interest in the asset.

This blend of technical and financial expertise has served the company – and any company it has an interest in – well. Backed by a long-term investment philosophy where its funds are 12 years in duration, the company can make moves aligned with the realities and timelines associated with turning assets into mines.

The next asset on the Appian books likely to move into construction-ready territory is Kalbar Operations’ Fingerboards mineral sands project, which focuses on the Glenaladale deposit, about 20 km northwest of Bairnsdale in Victoria, Australia.

Scherb said this project will be “build-ready” very soon, explaining that it is currently going through the permitting stage.

The project has the potential to be one of the world’s major producers of zircon, ilmenite, rutile and rare earths, and Kalbar is proposing an investment of over A$200 million ($148 million) in the development of a project able to produce around 575,000 t/y of heavy mineral concentrate over 15-20 years.

Scherb said Appian is keen to further pursue commodities associated with the electrification of industry, but he is aware of the premiums that may come with these deals.

“A lot of money has flooded into the battery metals,” he said. “We can be patient and are starting to look earlier stage in some investments.”

“Earlier stage” still has the potential to be producing in four- or five-year’s time, he clarified.

What’s clear is that the Appian team is gaining widespread recognition, with Scherb saying larger mining companies are starting to approach them with proposals that would see Appian gain operational control of assets, realising the firm has the right blend of “operational skill” and “value principles” to succeed.

Having acknowledged a skills shortage across the sector – one Appian is doing its bit to tackle with internship programs with universities in Canada, the UK and Australia – Scherb was confident the company’s talent would be retained and, ultimately, grow.

“In terms of talent retention, we at Appian offer experience of reviewing many different assets at different times in their lifecycle,” he said. “If you’re in-house at a mining company, you run the ruler over the same assets, stress testing them against different scenarios. We offer our teams variety that they cannot get in many places.

“At the same time, our structure means employees invest directly in companies to ensure they are correctly incentivised. This means they get to share in the profits.”

With plans to make one-to-three investments per year – along with the same number of exits – and expectations of committing its latest $775 million fund within the next two quarters, expect to hear more from Appian into 2022.

MVV, Appian hit construction milestone at Serrote copper-gold mine

Mineração Vale Verde Ltda and Appian Capital Advisory have finalised construction of the Serrote copper-gold mine and processing plant in Alagoas, Brazil, ahead of schedule and under budget.

Construction was concluded safely, while managing the challenges posed by the global COVID-19 pandemic, the companies reported.

The focus is now on the transition to steady-state operations and the ramp-up over the second half of 2021, with operational readiness workstreams, employee training programs and risk management workshops well advanced, MVV said. MVV’s first shipment of concentrate is targeted for November 2021.

This follows the announcement in February that MVV had secured a $140 million project finance debt facility, the largest independent greenfield mining project finance transaction announced since the beginning of 2020 and the onset of COVID-19, according to the company.

MVV will produce a high grade bornite-chalcopyrite copper concentrate, with gold and silver by-product credits. The company expects the high-grade nature of the concentrate to yield a premium in the market, while lowering the downstream transport costs and carbon footprint compared with typical copper concentrates.

Serrote will produce an average of approximately 22,000 t/y of copper equivalent over an initial 14-year mine life from a low-strip, open-pit mine supplying a 4.1 Mt/y processing plant. This initial life of mine will exploit a mineral reserve of 52.7 Mt grading 0.6% Cu and 0.1 g/t Au.

MVV says it is working towards unlocking substantial value upside through definition of an expansion plan into the larger 108.9 Mt measured and indicated resource at Serrote, as well as developing plans to generate value through the known oxide resource and nearby satellite deposits which are currently being drilled and expanded.

Paulo Castellari, CEO MVV & Appian Brazil, said: “Concluding construction in line with schedule and below budget once again demonstrates the success of Appian’s business model, and I am particularly proud of our leading safety record and ability to exceed expectations despite the pandemic.

“In Serrote we have a high-quality asset with low production costs, a long mine-life and significant upside from potential further expansion. Copper remains an incredibly attractive commodity and MVV is ideally placed to benefit from the growing global focus on electrification and decarbonisation.”

Appian, Atlantic Nickel reinvigorate Santa Rita as nickel sulphide fortunes rise

At the height of the most recent nickel boom – when prices were over $20,000/t on the LME – the Santa Rita mine looked like a great option to gain exposure to the stainless steel raw material.

Mirabela Nickel, the mine owner, represented a pure-play nickel stock; Brazil, as a jurisdiction, was looked at favourably by investors; and the operation, itself, was one of the largest open-pit nickel sulphide mines in the world slated to produce 16,500 t/y of nickel sulphide in concentrate.

Gaining exposure to such a large, low grade asset is great when the underlying commodity price is tracking well, but, as has been shown time and again, it proves problematic when the price moves south.

Such a price deterioration came to pass in the years following the mine’s start up in 2009.

The asset, in north-eastern Brazil, was eventually placed on care and maintenance in the March quarter of 2016 as Mirabela Nickel declared bankruptcy. This was the same year the nickel price dipped below $10,000/t.

Fortunately for the local community and personnel that had invested much hope in the development of the $1 billion-plus mine, Appian Capital Advisory more recently took the view that there was a way forward for Santa Rita.

Picking up on an emerging trend for clean and green nickel sulphide concentrate from the electric vehicle and stationary storage market, plus the ability to re-engineer the operation and make it a much more robust asset, the company carried out a six-month due diligence process on Santa Rita.

This process led Appian to refine its understanding of the presence of nickel sulphides within the deposit, as opposed to the asset’s total contained nickel. With this understanding in hand, a more defensive and low-cost mine plan was developed to see the asset through nickel price peaks and troughs.

Appian ended up acquiring Santa Rita and setting up the Atlantic Nickel operating entity to enact these changes.

Having restarted open-pit mining just over a year ago, the asset is starting to pay back the faith Appian has placed in this plan.

“Our resource now focuses on the estimation of nickel sulphide within the deposit and benefits from additional drilling we’ve undertaken post-acquisition,” Adam Fisher, Principal, Appian Capital Advisory LLP, explained to IM. “The mine design we’ve developed extracts the deposit more selectively and also moves less waste, resulting in the low cost performance we’ve been able to achieve to date.”

In the first half of 2020, the company declared first quartile C1 cost performance of $3.17/lb ($6,989/t) nickel, net of by-products. This compares favourably with Mirabela Nickel’s $6.19/lb operating cost recorded in the September quarter of 2013.

“Among the operating changes we’ve implemented are the use of a smaller, locally procured, equipment fleet of 40 t trucks (Santa Rita previously used Caterpillar 777 90 t and 785 137 t payload trucks), the use of shorter benches – we’ve gone from 10 m down to, on average, 6 m – and tighter blasting patterns,” Fisher said.

All this work is being carried out by a Brazil-based consortium of contract miners.

“With smaller benches, tighter blasting patterns and smaller equipment fleets, we have more consistent control on the grade and fragmentation of the material that is fed to the crusher,” Fisher said.

The focus has gone beyond the near term, with more than 100,000 m of drilling executed in the underground resource area. The drilling was optimised for resource growth and classification confidence. The program was extremely successful and supported the declaration of the underground resource of 168 Mt at 0.59% NiS and 0.19% Cu. The 2020 drill programs continue to intersect similar widths and grades while stepping out from the declared resource, the company added.

The NI 43-101 technical report, released earlier this month, outlined a 34-year mine life for Santa Rita, with eight years of open-pit production, underpinned by proven and probable reserves of 50.6 Mt at 0.31% NiS, followed by 26 years of underground mining.

While still preliminary, this represented a very different approach to the previous Santa Rita owner.

“The last owners designed an open-pit mine with a 6:1 strip ratio and were planning to mine a lot deeper into the resource via open-pit methods,” Fisher said. “This was back in a very different nickel market when prices were greater than $10/Ib.

“All we did was find the optimal transition to bulk methods at depth to understand that it only makes sense to mine this as an open pit over eight years at a strip ratio that comes down to, on average, 2.7:1.”

Backing up this open-pit mine plan has been a 6.5 Mt/y plant, which, having started production in 2009, was completely refurbished and recommissioned in the second half of 2019 to align with the nickel sulphide recovery focus.

The plant consists of crushing, grinding, flotation, thickening and filtration unit operations to produce a saleable nickel sulphide concentrate. Flotation tailings are pumped to a tailings storage facility, while grinding is performed by a SAG mill, two ball mills and two pebble crushers. This is followed by a conditioning circuit and a flotation circuit, with the final concentrate thickened and pumped to storage tanks ready for filtration. Concentrate is filtered in a Larox (Metso Outotec) pressure filter. Following filtration, the final concentrate is trucked to the port of Ilhéus where it is loaded onto ships for transport to market.

Since the restart, more than five shipments have been made to the mine’s offtake partners.

“While the mine and plant are still ramping up, the open-pit operation is not far off from achieving the PEA estimates of being able to produce 20,000-25,000 t/y of contained nickel sulphide equivalent at a C1 cost of $2.97/Ib nickel,” Fisher said.

Beyond this, the company is looking to leverage innovation to create one of the largest and most efficient sub-level cave (SLC) operations in the world able to produce more of the highly sought after nickel sulphide product Santa Rita is becoming known for.

Caving in

“When carrying out the due diligence on Santa Rita, we knew all along that there was some good, thick intersections underground, with the orebody getting thicker at depth and the nickel sulphide grade improving,” Marcus Scholz, Head of Underground Mining at Appian Capital Advisory, told IM.

This was evident in the PEA, with underground mining inventory of 134.1 Mt grading 0.54% NiS and 0.17% Cu, comparing favourably – in terms of grade – with the proven and probable reserves of 50.6 Mt at 0.31% NiS and 0.11% Cu calculated for the eight-year open-pit operation.

“You’re looking at a massive orebody with moderate grades,” Scholz said. “Factoring that in, the lowest cost methods will generate the better margins in this case. With SLC having come a long way in the last 20 years in terms of practices, philosophies and the ability to control dilution through effective planning and modelling, plus the suitable geometry of the Santa Rita orebody, it was a good fit.”

This low-cost caving method allows the company to exploit more of the resource than other methods such as long-hole open stoping with backfill, plus fill the existing plant, Scholz explained.

Scholz was keen to point out that the company did not come to this conclusion on its own. It sought assistance from Power Geotechnical out of Australia, which has worked on other sub-level cave operations such as Carrapateena and Ernest Henry, when assessing its options.

Ernest Henry, operated by Glencore in Queensland, Australia, is a good analogue here. The Ernest Henry orebody is located at a similar depth below a pit and has a similar width and dip, but Santa Rita is about twice the size due to it being longer along strike, according to Scholz. It also comes with a similar 6 Mt/y profile.

Photography of Glencore’s Ernest Henry Mine near Cloncurry in Western Queensland

The SLC mining layout in the PEA comprises 37 mining levels spaced at vertical intervals of 25 m. Each level is made up of parallel and evenly spaced drill drives from which production drilling and blasting occur. Once blasted, the mineralisation is loaded from the drill drives using LHDs and loaded into trucks for haulage to the surface during the initial ramp-up phase, and later to ore passes feeding an underground crushing station and conveying to surface via an inclined tunnel.

The PEA plans will have the company mine directly beneath the open pit to start with, hence the reason it expects to start up production in 2028 after open-pit mining has concluded.

The underground operation will start with two years of waste development ahead of ore production, followed by ore truck haulage over a three-year period, Scholz outlined. After this, the operation will transition to underground conveyor haulage, ramping up to 6 Mt/y capacity over the next four years.

Asked why the company was starting with truck haulage before moving to conveyors, Scholz said it was an economic decision.

“If we truck first, we can delay some of the underground spend in terms of getting the underground crusher in,” he said.

Over the life of the underground mine, the company plans to install two underground crushers, being fed with roughly equal amounts of ore. The first will serve the upper half of the deposit and the second crusher the lower half (circa-6 Mt/y each, staged as mining progresses deeper in the deposit).

The first crusher will be positioned about 650 m below surface, or 450 m below the ultimate depth of the open pit.

“This will take a bit of time to get down there and access it (in terms of mine development), so it makes sense to start haulage with trucks,” Scholz said.

Appian is looking to lease the 60 t trucks required for this stage of the operation, explaining that Atlantic Nickel will operate the 12 machines needed at the height of truck haulage, which is when mining rates hit the annualised 2.5 Mt/y mark.

The truck haulage route will be a short one, travelling some 200-300 m below surface to access material before going back above ground.

After the conveyor transition, the trucks are expected to be used in later years for waste haulage, which could amount to some 500,000 t/y of material, according to Scholz.

Automation and electrification transition

It is when the conveyor starts up that the automation element of Santa Rita Underground really kicks into gear.

The company assumed the use of automated LHDs, longhole drilling and jumbo development drilling in the PEA. This saw Epiroc, Caterpillar and Sandvik provide price inputs, with design layouts anticipating such equipment.

Scholz expanded on this for IM: “We foresee that loaders going from the SLC drawpoints to the ore passes would be automated, meanwhile, at the collection level at the bottom of ore passes, we would probably have up to three large automated loaders that transfer material to the crusher.”

Longhole drills would also be automated for the SLC, while the company plans to automate face drilling activities on the development jumbos it will use.

“I think in another eight years’ time when we start up production, a lot of this technology is going to be the norm in the industry,” Scholz said.

The current study assumes the use of a diesel-powered load and haul (initially) fleet, though electric vehicles could provide upside in future studies and further reduce energy costs, equipment maintenance costs and ventilation power costs, an Appian spokesperson recently told IM.

“Both tethered- and battery-powered machines will be looked at for specific applications within the mine, such as loading from drawpoints and feeding the underground crusher from the bottom of ore passes,” the spokesperson explained.

While much of the industry’s larger load and haul equipment has not yet made the commercial leap to battery power, the company is keen to pursue developments in the future as the technology became available, Scholz said.

The circularity of such a move will not be lost on Appian or Atlantic Nickel, knowing the nickel sulphide concentrate it will be offloading could end up in these battery-powered machines. In eight years, these end users will most likely be factoring such emissions-reducing technology into their raw material procurement choices.

For the time being, the company is focused on completing the underground drilling program at Santa Rita, which has, to date, shown much promise.

Fisher said every hole has intersected nickel sulphides to this point meaning the chances of a further underground resource upgrade in the early part of next year were high.

These figures will be factored into a prefeasibility study later in 2021, which will include more detailed geotechnical information on the SLC, as well as subsidence modelling, Scholz said.

Atlantic Nickel ready to delve underground for Santa Rita mine life expansion

Atlantic Nickel has released a preliminary economic assessment (PEA) on its Santa Rita nickel mine, in Brazil, that shows the potential for the company to become one of the largest sustainable nickel sulphide producers in the world.

The announcement, made in concert with Appian Capital Advisory LLP (the owner of Atlantic Nickel), follows the recommencement of open-pit mining at Santa Rita in August 2019.

This new NI 43-101 technical report outlines a 34-year mine life for Santa Rita, in Bahia, with eight years of open-pit production, underpinned by proven and probable reserves of 50.6 Mt at 0.31% NiS, and 26 years of underground mining.

The open-pit mine plan was prepared to prefeasibility study level and encompasses a large open pit and a nearby, much smaller satellite open pit along strike. Both pits will be mined with conventional mining equipment, and the plan will be executed in 10 phases, the company says.

The open pit is scheduled over a period of eight years, ending in 2028, with operations using standard methods of drilling and blasting, loading, and hauling. It would produce 20,000-25,000 t/y of contained nickel equivalent at a C1 cost of $2.97/lb Ni and an all-in sustaining cost (AISC) of $4.12/lb Ni, the company says.

The Santa Rita process plant, having started production in 2009, was completely refurbished and recommissioned in the second half of 2019 in line with the mine restart. The plant consists of crushing, grinding, flotation, thickening and filtration unit operations to produce a saleable nickel concentrate. Flotation tailings are pumped to a tailings storage facility, while grinding is performed by a SAG mill, two ball mills and two pebble crushers. This is followed by a conditioning circuit and a flotation circuit, with the final concentrate thickened and pumped to storage tanks ready for filtration. Concentrate is filtered in a Larox (Metso Outotec) pressure filter. Following filtration, the final concentrate is trucked to the port of Ilhéus where it is loaded onto ships for transport to market.

The mineral resource estimate for the expansion case consists of 94.2 Mt of measured and indicated resources across open-pit and underground mining at average grades of 0.41% NiS, 0.14% Cu, 0.01% Co, 0.03 g/t Pd, 0.07 g/t Pt and 0.05 g/t Au, with 90.6 Mt of inferred resource at 0.54% NiS, 0.17% Cu, 0.02% Co, 0.04 g/t Pd, 0.09 g/t Pt and 0.06 g/t Au.

Sublevel Caving (SLC) was selected as the mining method for the underground portion of the deposit based on the amenable geometry of the deposit, and because productivity and cost advantages of SLC enable greater exploitation of the underground resource at greater margin than more selective mining methods, Atlantic Nickel said.

“The geometry of the deposit and the location below a mined open pit are similar to the Ernest Henry SLC, which is successfully operated by Ernest Henry Mining (a subsidiary of Glencore) in Queensland, Australia,” the company added.

The SLC mining method employs long-hole drilling and blasting techniques to extract mineralisation sequentially from the surface to the bottom of the deposit. The method does not require backfill and, therefore, relies on the overlying waste rock to cave and fill the mined void, the company explained. Caving of the overlying waste rock results in surface subsidence above and in the immediate vicinity of the underground deposit, but the subsidence will not interfere with open-pit mining since initial production from underground is planned to commence in 2028 when open-pit mining is completed.

Infrastructure capital and development of the underground project is planned to start at the beginning of 2026, with production from the underground ramping-up over a seven-year period until full production of 6.2 Mt/y is achieved.

The underground portion of the resource considered in the PEA plan consists of 43.5 Mt of indicated resources and 90.6 Mt of inferred resources. This resource was used to come up with a 40,000-45,000 t/y of contained nickel equivalent production profile for the underground operation over life of mine at a C1 cost of $2.17/lb Ni and an AISC of $3.92/lb Ni.

The SLC mining layout in the PEA comprises 37 mining levels spaced at vertical intervals of 25 m. Each level is made up of parallel and evenly spaced drill drives from which production drilling and blasting occur. Once blasted, the mineralisation is loaded from the drill drives using LHDs and loaded into trucks for haulage to the surface during the initial ramp-up phase, and later to ore passes feeding an underground crushing station and conveying to surface via an inclined tunnel.

“The SLC method employs a top-down mining sequence that enables production to ramp-up quickly once the top of the underground deposit has been accessed,” Atlantic Nickel says. “The method also enables high production rates as the mining cycle is simplified by the standardisation of development and production and with no backfilling required.”

While still early days in terms of the underground mine’s development plans, the company assumed the use of automated LHDs, longhole drilling and jumbo development drilling in the PEA, a spokesperson for Atlantic Nickel confirmed to IM. This saw Epiroc and Sandvik provide price inputs, with design layouts anticipating such equipment.

“Subsequent studies will optimise the equipment and layouts integration,” the spokesperson added.

And, while the current study assumes the use of a diesel-powered fleet, battery-electric vehicles will also provide upside in future studies and further reduce energy costs, equipment maintenance costs and ventilation power costs, the spokesperson said.

“Both tethered and battery will be look at for specific applications within the mine such as loading from drawpoints and feeding the underground crusher from the bottom of ore passes,” the spokesperson said.

The flotation test work gave similar results to those obtained with open-pit material; hence, plant performance is not expected to be significantly different for underground material, the company said. Underground feed will be treated in Atlantic Nickel’s existing process plant with only minor modifications required, likely to the grinding circuit.

New surface infrastructure associated with the underground mine would include the following:

  • A box cut and portal located to the west of the north end of the open pit;
  • A conveyor portal connecting to the bottom of the existing crusher installation;
  • A temporary construction portal in the west wall at the north end of the open pit on the 82 m RL bench;
  • Multiple ventilation raise surface collars on the western side of the open pit;
  • Ventilation adits on the west wall at the south end of the open pit on the 10 m RL bench;
  • Dewatering pond for storing, settling and recycling water from underground;
  • Electrical reticulation to the portals, adits and services; and
  • Shotcrete batch plant.

After completion of open pit mining, a new tailings storage facility would be required to store the additional 134 Mt of tailings to be produced from the underground mine over a period of 28 years. Like the existing tailings storage facility, raises will be constructed using a downstream method, the company said.

Total capital associated with the underground expansion amounts to $1.3 billion over the 34-year combined operation, with only $355 million of that being spent during the first five years of underground development commencing in 2026. The expansion is partially self-funding with cash flows generated from the open-pit mining operation, the company said.