Tag Archives: Brazil

Giga Metals taps Minerva’s AI prospect generator software for Brazil exploration

Minerva Intelligence says its Cognitive artificial intelligence-powered prospect generation software, TARGET, has helped Giga Metals identify and evaluate new prospective exploration targets at the Parnaiba Basin project in Nordeste, Brazil.

Giga, after validating the results produced by Minerva’s TARGET software, made the decision to acquire exploration permits covering significant new regional sediment-hosted copper anomalies along the southern perimeter of the Parnaíba Sedimentary Basin in southern Piauí State, Northeast Region, Brazil, it said.

This amounted to the staking of 24 exploration permits totalling 40,722 ha in four properties along 80 km of strike length in an area with known “Kupferschiefer-style” sediment-hosted copper mineralisation.

Scott Tillman, CEO of Minerva Intelligence, said: “The commercial validation of our TARGET software is yet another indication of the power of Minerva’s Cognitive AI-powered software.

“The successful deployment of our TARGET software highlights the value we are able to provide to companies that are managing large datasets and seeking to incorporate an artificial intelligence element into the decision-making process. Our success with Giga in Brazil, in conjunction with our recent success in Mexico, points to even greater success in the future in delivering results for mining and exploration companies around the world.”

Using Minerva’s TARGET software, Giga was able to sift through, organise and evaluate large datasets that were subsequently used to analyse the validity of the prospective exploration region, Minerva explained. TARGET’s mapping technology was able to determine, based on existing comprehensive datasets, that the project in Brazil had a high likelihood of success and, as a result, Giga should pursue investment in the region.

The final result of the analysis was a list of AI-produced target areas throughout Brazil that are completely auditable and explainable, and, most importantly, actionable by Giga, Minerva said.

Giga Metals CEO, Mark Jarvis, said: “TARGET enabled us to work our way through an immense volume of regional geological data to focus on areas prospective for the deposit types of interest to us. This is a type of regional survey that was previously possible only for a major mining company with a large team of geologists. It is exciting to experience at first-hand how artificial intelligence is now making this type of survey accessible to smaller companies.”

Jake McGregor, Minerva’s COO, added: “In 2019, Minerva was contracted by Giga to build a set of prospectivity maps for the country of Brazil. In this capacity, the company compiled various datasets from across the country, both from public and private sources, and significant work was undertaken by Minerva to standardise and translate the data from Portuguese to English, and then into the standard terminologies that we use in our mineral deposit models. It is extremely rewarding to see our clients getting value out of that hard work.”

Amarillo Gold powers up Posse gold development with Enel Brasil deal

Amarillo Gold Corp says it has made a significant step toward building its Posse gold mine in Brazil, signing a commitment agreement with Enel Brasil, the state electric power utility, to build a dedicated power line to the company’s Mara Rosa Property in the State of Goiás.

Arão Portugal, Amarillo’s Country Manager for Brazil, said: “Once complete, this power line will be a much-needed lasting legacy, enhancing the power grid infrastructure of the communities in and around Mara Rosa. It also represents our commitment to operational excellence and building strong local infrastructure.”

The 67-km-long 138 kV power line will connect Posse with the Porangatu substation and supply all of the electricity needed for the project. Amarillo is overseeing the engineering and permitting process, assisted by Enel. Construction can start once the permit for the power line is received. It will cost about BRL36 million ($6.6 million) to build and is expected to take around 12 months.

A definitive positive feasibility study released in June showed that Posse is expected to produce gold at an all-in sustaining cost of $656/oz, based on a gold price of $1,730/oz and a foreign exchange rate of 5.3 BRL to one US dollar. It came with an initial mine life of 10 years, initial gold production of 104,000 oz/y, and an after-tax net present value (5% discount) of $360 million.

Mike Mutchler, Amarillo’s Chief Executive Officer, said of the power line progress: “We have achieved another important milestone in Posse’s development, even as we wait for the License to Install (LI) from the state regulators.”

The governor of the State of Goiás signalled work was progressing on finalising LIs for 14 mining projects in Goiás during a meeting announcing mining investment in the state on January 25.

Meanwhile, LQ Consulting and Management Inc has been hired as Amarillo’s project management team for Posse, and has begun work on a project execution plan that will help management re-evaluate the construction timeline.

Yamana Gold evaluates Jacobina backfill plant, underground mine at Canadian Malartic

Yamana Gold says it is evaluating the installation of a backfill plant at its Jacobina gold mine in Brazil (pictured) in a move that would reduce the asset’s environmental footprint, as well as extend the life of the operation’s existing tailings storage facility.

The backfill plant would allow up to 2,000 t/d of tailings to be deposited in underground voids, Yamana said in its 2021-2023 guidance and 10-year overview release.

The miner said the construction and operation of a backfill plant would also improve mining recoveries at the operation, resulting in increased conversion of mineral resources to mineral reserves.

Jacobina produced 44,165 oz of gold during the December quarter and an all-time high of 177,830 oz for 2020, the company reported in a separate release.

This was the seventh consecutive year of increasing production at the operation, a trend that is expected to continue in the coming years, Yamana said.

“Successful infill and exploration drilling in the Canavieiras and João Belo sectors during 2020 continues to generate significant growth potential,” the company added.

Production in 2021 is forecast to be in a similar range to the 177,830 oz recorded in 2020, Yamana said.

“The operation exceeded the targeted throughput rate of 6,500 t/d for the Phase 1 expansion, and it continues to identify and implement additional processing plant optimisations to further increase throughput, improve recoveries and reduce costs,” the company said. “Beyond further optimisations, the feasibility study for Jacobina’s Phase 2 expansion plans to increase throughput to 8,500 t/d and raise annual production to 230,000 oz remains on track for mid-2021.”

Yamana’s base case in its 10-year overview also included production from an underground mine at the Canadian Malartic operation in Quebec, Canada. This consists of the East Gouldie, Odyssey, and East Malartic zones, (collectively known as the Odyssey project).

Owned 50:50 by Yamana and Agnico Eagle, the Canadian Malartic open-pit mine exceeded its revised 2020 guidance, producing 568,000 oz of gold (on a 100% basis). Production last year was impacted by COVID-19 related restrictions on mining in Quebec and is forecast to increase in 2021 to 700,000 oz, with all-in sustaining costs projected to decline to $850-$885/oz, from $945/oz in 2020.

The Canadian Malartic open pit will be depleted in the first half of 2023, and waste rock and tailings will be deposited into the pit beginning in 2023, Yamana says.

This coincides with planned first production from the Odyssey South zone at the underground project, with the Upper East Gouldie zone expected to come online in 2027.

The most recent underground mineral resource for the project, which was published in February 2020, showed more than 10 Moz of gold (100% basis), including 9.6 Moz ounces of inferred mineral resources (100% basis) and 830,000 oz of indicated mineral resources (100% basis).

“In the interim, exploration results have been exceptional, improving economics and increasing confidence that the underground project will be a multi-hundred-thousand-ounce annual producer for decades,” Yamana said.

Key development milestones for the underground project over the next three years include the development of a ramp into the Odyssey, East Malartic, and East Gouldie zones, which will allow for tighter definition drilling to further expand the mineral resource base, along with headframe construction and shaft sinking, Yamana said.

A preliminary economic assessment for the project is expected to be completed in February.

Jervois Mining looks to POX leaching to boost SMP nickel-cobalt refinery recoveries

Jervois Mining says it plans to integrate a pressure oxidation leach (POX) circuit into the São Miguel Paulista nickel-cobalt refinery in Brazil.

Jervois paid the first tranche towards its acquisition of SMP refinery in December after announcing plans to acquire the refinery in September 2020. The acquisition aims to complement its 100%-owned Idaho Cobalt Operations (ICO) in the US, transforming Jervois into a vertically integrated producer capable of refining cobalt and nickel.

The company appointed Australia-based Elemental Engineering to commence sysCAD modelling of the SMP refinery flowsheet for optimisation of product integration, including hydroxides and carbonate products, oxides and sulphide concentrates as part of a feasibility study (FS) for SMP’s restart.

As a result of Elemental’s work, Jervois has determined it shall integrate a POX leach circuit at the refinery.

“The inclusion of the POX autoclave offers a number of advantages compared to roasting concentrates, namely high metal recovery, low overall operating costs, enhanced ESG metrics due to lower emissions and energy usage, improved refined product purity and compact installation footprint on site,” the company said. “Preliminary POX sighter testwork at SGS Perth Western Australia, in conjunction with Elemental’s work, returned satisfactory results.”

While POX comes with a higher capital expense than roasting alternatives, it is a commercially demonstrated technology with low technical risk, allowing Jervois to leverage its recently appointed commercial team, Jervois said. A POX autoclave better compliments the refinery flowsheet, unlocks sunk capital by debottlenecking the existing leach capacity and adds significant flexibility to future refinery feed options, it added.

Jervois will process sulphide concentrate produced from ICO via this integrated POX leach circuit, with Jervois’ commercial team actively pursuing supply contracts for nickel and cobalt intermediate products. The introduction of a POX autoclave opens up greater capacity to leach other hydroxide and carbonate feed products to maximise existing refinery capacity, the company said.

Third-party concentrates can also be potentially introduced into the POX to process with Jervois’s ICO concentrates. Early discussions with potential third-party suppliers of sulphide-based concentrates have been positive, with the company now openly engaging with suppliers to optimise the sizing and economics of front-end pre-treatment.

As part of this, a decision has been made to reserve the maximum amount of copper capacity at SMP refinery for third parties. A consequence is that ICO construction is being advanced on the basis of the production of separated cobalt and copper concentrates. Jervois’s engineering advisers, DRA Global and M3 Engineering, completed the ICO BFS on both bulk and separated concentrate flowsheets, with construction plans being implemented based on the production of cobalt concentrate (containing gold and low in copper) and a copper concentrate. Commercial terms were obtained for both separated products as part of the BFS.

Jervois says it and Companhia Brasileira de Alumínio (CBA), the current owner of the SMP refinery, continue to work expeditiously towards closing Jervois’ acquisition of SMP.

Jervois plans a measured and staged approach to the refinery facility restart. Initial refurbishment works will be completed to progress the processing of intermediate hydroxide and carbonate products followed by the integration of the POX leach circuit to align with ICO commissioning, it said.

Jervois is in discussions with suitably qualified engineering contractors that have the appropriate nickel and cobalt refining experience, have a significant presence in Brazil, and have recently completed a POX and metals plant installation, to award the BFS for the refinery restart. This formal tender process is underway.

Vale given the go ahead to start Capanema iron ore construction

Vale says it has received the required licences to start construction of the Capanema iron ore project in Minas Gerais, Brazil.

The project involves the development of the Capanema mine, acquisiion of new equipment, implementation of a long-distance 2.4 km conveyor belt (TCLD, pictured) and adjustments in the Timbopeba stockyards. This is expected to amount to multi-year investments of $495 million.

With the start-up expected for the second half of 2023, the project will have a production capacity by natural moisture (without tailings generation) of 18 Mt/y and, in the first years, will bring a net addition of 14 Mt/y of capacity to Vale with the “expedition” through the Timbopeba site, Vale said.

The start of the construction works of Capanema marks another important step in productive capacity buffers creation, ensuring greater operational flexibility with low capital intensity, Vale said.

Vale has previously identified that Capanema could be one of its new operations to use “dry processing” techniques.

ERG’s BAMIN iron ore project kicks into gear

Eurasian Resources Group says it is continuing to advance its BAMIN integrated iron ore mining and logistics project in Brazil with the planned commercial start-up this month of its Pedra de Ferro mine in Bahia.

Pedra de Ferro has an initial capacity of 2 Mt/y of high-grade iron ore with 65% Fe content, but, in full production, will be able to produce 18 Mt/y of ore.

At the same time as this, plans for the implementation of Porto Sul, a deep-water port complex that is part of BAMIN, also continue to advance.

Carried out by the State of Bahia and BAMIN, the initial works at the port (pictured) focus on the construction of the requisite infrastructure and access to the site. This phase of the work will generate 400 direct jobs and another 1,200 indirect jobs, according to ERG.

Overall, the BAMIN project is expected to see Bahia become the country’s third largest iron ore producer.

Benedikt Sobotka, CEO of ERG, said: “The start of operations at Pedra de Ferro is a fundamental step towards the full implementation of the project. Porto Sul, in addition to its strategic importance, will strengthen the local economy and support the growth of other sectors. While implementing the BAMIN project, we also aim to positively contribute to the economic and social recovery and help mitigate the long-term impact of the pandemic.”

EXPOSIBRAM expo and congress moves online

One of the most relevant and well-attended business-promoting events for the Latin America mineral sector will be going 100% online this year.

EXPOSIBRAM – Expo & Congresso Brasileiro de Mineração 2020 will be held from November 24-26, with free registration available for the virtual event.

In addition to its renowned Brazilian Mining Congress, another attraction of the event will be the online business meeting function, which will enable large mining companies and suppliers from various sectors to connnect.

EXPOSIBRAM will also hold space for technical lectures and short courses, all guided by the Brazilian Mining Institute (IBRAM).

Mining companies already confirmed to attend the event include sponsors Vale, Mosaic Fertilizantes, Anglo American, Kinross Paracatu, CMOC Brasil, Horizonte Minerals, Mineração Usiminas and Serabi Gold.

To find out more information on the event and register, click here.

International Mining is a media sponsor of EXPOSIBRAM 2020

Anglo American to introduce LNG into iron ore chartering fleet

Anglo American has announced the award of a 10-year charter contract for four LNG fuelled capesize-plus vessels, introducing LNG into its chartered fleet for the first time.

The new build LNG vessels offer significant environmental benefits, including a circa-35% cut in CO2 emissions compared with standard marine fuel, while also using new technology to eliminate the release of unburnt methane, or so-called “methane slip”, the company said.

Peter Whitcutt, CEO of Anglo American’s Marketing business, said: “Anglo American is committed to reducing emissions from its ocean freight operations and to playing a leading role in shaping a more sustainable future for the maritime industry. Today’s agreement is aligned with Anglo American’s goal to be carbon neutral across our operations by 2040 – as we work to reduce emissions not only at our production sites but also along our entire value chain – and builds on our track record of implementing concrete actions to deliver on the targets set by the International Maritime Organisation’s 2018 strategy.

“LNG is a readily available, commercially viable, lower emission solution which, combined with innovative technology designed to eliminate unburnt methane, will allow these new builds to provide a much improved environmental and more efficient performance.”

LNG marine fuel offers significant environmental advantages over heavy fuel oil – the most widely used fuel by vessels operating along sea trade routes – and is abundantly available through an established global network of existing infrastructure, according to Anglo American. Compared with conventional fuel options, the use of LNG eliminates sulphur oxides, considerably reduces nitrogen oxides and particulate matter from vessel exhausts and, as mentioned, cuts CO2 emissions by around 35%.

Designed to be larger than, but remain as flexible as, a conventional capesize vessel, the new builds will optimise cargo transport by increasing load and improving overall cost effectiveness. U-Ming Marine Transport will own the newly designed 190,000 DWT LNG fuelled bulk carriers. The fleet will be built by Shanghai Waigaoqiao Shipbuilding in China and is expected to be delivered in 2023.

The fleet is expected to carry up to 5 Mt/y of product, transporting iron ore from Anglo American’s operations in Brazil and South Africa to the company’s global customer base. The new builds will be flagged and registered in Singapore, which will also serve as prime bunkering port, thereby avoiding deviations from trading routes for refuelling purposes, the company said.

Earlier in October, Anglo American was among the founding signatories of the Sea Cargo Charter – created by some of the world’s largest energy, agriculture, mining, and commodity trading companies, with the aim of establishing a standard methodology and reporting framework to allow charterers to measure and align their emissions from ocean transportation activities.

US DFC investment paves way for Piauí nickel-cobalt production, TechMet says

The US International Development Finance Corp (DFC) has made a $25 million investment into TechMet Ltd, a private investment company with a portfolio of projects that produce, process and recycle metals tied to the production of electric vehicles (EVs), renewable energy systems and energy storage.

The funds will be used to bring into initial commercial production one of TechMet’s core investments, Brazilian Nickel Plc, which will be a low-cost nickel-cobalt producer in Piaui, in north-eastern Brazil, it said.

Piauí is a nickel laterite heap leaching project that has a combined measured and indicated JORC compliant resource of 72 Mt at 1% Ni and 0.05% Co. Brazilian Nickel has previously completed a large-scale demonstration of the heap leaching, purification and recovery of nickel and cobalt from the Piauí ore (pictured).

The DFC investment, part of TechMet’s Round 2 equity raising, follows on the heels of US President, Donald Trump, signing an Executive Order and declaring a National Emergency to expand the domestic mining industry, support mining jobs, alleviate unnecessary permitting delays, and reduce the US’ dependence on China for critical minerals.

Nickel and cobalt are two key ingredients in the production of lithium-ion batteries that power EVs and provide renewable energy storage. As battery technologies transform the global mobility and energy landscape, the demand growth for these metals is expected to accelerate.

TechMet said: “While China has built a position of overwhelming supply chain dominance, the United States’ continued reliance on imports for the supply of critical metals represents a significant threat to the long-term competitiveness of American industry. TechMet, aligned with US interests, is committed to developing an independent supply of these critical metals.”

Brian Menell, Chairman and CEO of TechMet, said: “We are very pleased to have secured this funding and support from DFC, which enables Brazilian Nickel Plc to begin the commercial production of nickel and cobalt products used in the production of EV batteries. Having this level of US support is a great endorsement of TechMet’s team and strategy.”

Adam Boehler, CEO of the US International Development Finance Corp, a US Government agency, said: “This important financing will support economic growth in one of Brazil’s most underdeveloped areas. Investments in critical materials for advanced technology support development and advance US foreign policy.”

TechMet has been operational for three years and its core investments include:

  • Brazilian Nickel Plc;
  • Li-Cycle – lithium-ion battery recycling with a producing plant in Canada and a plant under construction in Rochester, New York;
  • US Vanadium – vanadium specialty chemicals production in Arkansas (USA); and
  • Tinco – one of the largest tin and tungsten mines in Rwanda.

TechMet also has an interest in a producing Rare Earths metals project and is developing TechMet Ventures to invest in new opportunities across the supply chain, it says.

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.