Tag Archives: Nevada

AngloGold investigating use of battery-electric vehicles at Cuiaba mine in Brazil

AngloGold Ashanti says it is weighing up the potential introduction of battery-electric vehicles at its Cuiaba mine in Brazil as a small part of a wider initiative to achieve a 30% absolute reduction in its Scope 1 and 2 Greenhouse Gas (GHG) emissions by 2030.

The company says this carbon emission reduction target could be met through a combination of renewable energy projects, fleet electrification and lower-emission power sources. The company has already reduced its absolute GHG emissions by more than two thirds since 2007, and remains committed to achieving net zero emissions by 2050.

The targeted reduction announced today, from a 2021 baseline of 1.4 Mt of carbon dioxide equivalent (CO2e), aims to see emissions from the company’s activities diminish to about 1 Mt by the end of the decade. When growth projects are factored in, including those in Nevada and Colombia, AngloGold Ashanti is targeting a 46% reduction in emissions by the end of the decade.

The capital cost required to achieve these reductions over the coming eight years is anticipated to be about $1.1 billion, of which $350 million will be funded over that period by AngloGold Ashanti and the remaining $750 million through third-party funding, including from providers of renewable energy infrastructure. The company plans in the coming weeks to initiate a process to secure a green funding facility of $250-300 million to finance its portion of these decarbonisation initiatives across its business.

“We have a clear pathway to achieve our target by 2030, when we expect to have lowered our overall emissions by almost a third,” AngloGold Ashanti Chief Executive Officer, Alberto Calderon, said. “This ensures we continue to do our part in reducing our carbon footprint, while also improving the value of our business.”

The targeted reductions announced today incorporate initiatives at each business unit including the introduction of renewable energy, cleaner grid power and partial fleet electrification.

Approximately 60% of the planned emissions reductions will come from large renewable energy projects including wind and solar projects at the company’s Australian operations and solar-power plants at both Siguiri in Guinea and the Iduapriem and Obuasi operations in Ghana, AngloGold said. In addition, a prefeasibility study has commenced at the Cuiaba mine in Brazil to confirm the benefits of replacing some mobile fleet with battery-electric vehicles. AngloGold will also be working with Sandvik to trial underground mining’s largest-capacity BEV truck, the 65-t payload TH665B at Sunrise Dam.

The Cuiabá complex includes the Cuiabá and Lamego underground mines and the Cuiabá and Queiroz plants. Ore from the Cuiabá and Lamego mines is processed at the Cuiabá gold plant. The concentrate produced is transported by aerial ropeway to the Queiroz plant for processing and refining. Total annual capacity of the complete Cuiabá circuit is 1.75 Mt.

The viability of a wind farm at Cerro Vanguardia in Argentina is also being investigated. The vast majority of these projects are expected to be NPV-positive adding value to the business by reducing energy costs and improving energy security, the company said.

Two “clean grid” initiatives are already close to completion – a switch from diesel generation at the Geita mine site in Tanzania to the country’s national power grid, which has a high proportion of power sourced from gas and renewables, and the transition to full hydro-grid power in Brazil.

Schlumberger’s NeoLith Energy taps Gradiant water solutions for direct lithium extraction work

Schlumberger has entered into a partnership with Gradiant to introduce a key sustainable technology into the production process for battery-grade lithium compounds, the global water solutions provider says.

As part of Schlumberger’s NeoLith Energy direct lithium extraction (DLE) and production flowsheet, Gradiant technology is being used to concentrate the lithium solution and generate fresh water – a critical element in sustainable lithium production from brine.

“Proper natural resource management is essential in mineral production, and nowhere more so than in lithium,” Gavin Rennick, President of Schlumberger’s New Energy business, said. “The unprecedented growth in demand for this critical mineral requires high-quality production without compromising sustainability. The integration of Gradiant technology into our DLE flowsheet has been key in our strategy to improve sustainability in the global lithium production industry.”

NeoLith Energy’s DLE process is in sharp contrast to conventional evaporative methods of extracting lithium, with a significantly reduced groundwater and physical footprint, according to the company. It currently has a pilot plant in Clayton Valley, Nevada, where it is putting this to the test.

Gradiant’s new solution enhances the impact of the sustainable lithium extraction process, reducing time to-market and the environmental footprint of the product, the company says. The technology enables high levels of lithium concentration in a fraction of the time required by conventional methods, while also reducing carbon emissions, energy consumption, and capital costs when compared with thermal-based technologies. This technology integration can be applied into new lithium mineral extraction and production sites, opening opportunities to untapped lithium production regions, as well as existing lithium production operations.

The collaboration will enable the lithium industry to meet surging mineral demand with a previously unattainable level of water utilisation, by simultaneously lowering the consumption of fresh water and reducing wastewater, according to Gradiant.

“We are excited to be working with Schlumberger, with whom we are pioneering a new era of sustainable mineral resource recovery,” Prakash Govindan, COO of Gradiant, said. “This is made possible by Gradiant’s deep understanding of the complex chemistry that underlies the production processes, which is then operationalised by machine learning and digital technology.

“The sustainability impact of the integrated Schlumberger process, combined with Gradiant solutions, is a game changer for the lithium production market. This strategic partnership will enable the global expansion of Gradiant’s technology in this important industry.”

i-80 Gold brings Hatch in to evaluate Lone Tree autoclave restart

i-80 Gold Corp has awarded the engineering study for restart of the Lone Tree autoclave in Nevada, USA, to Hatch Ltd.

The study will complete a prefeasibility study (PFS) level mechanical and operational review of all aspects necessary for the restart of the company’s autoclave processing facility in northern Nevada.

i-80 acquired the Lone Tree property and associated infrastructure capable of, it says, processing all Nevada ore types from Nevada Gold Mines in 2021. The Lone Tree complex includes an autoclave, floatation circuit, tailings compound and heap leach facility that will become the hub of i-80’s Nevada operations and, it says, provide the platform to realise its future production growth plans of becoming a 500,000 oz/y producer.

The study, combined with an extensive metallurgical program of the mineralisation from the company’s Granite Creek, McCoy-Cove and Ruby Hill projects, will allow management to consider a range of restart opportunities and associated capital costs, it said. In the interim period, i-80 has secured processing agreements with Nevada Gold Mines so that it can commence underground development at Granite Creek, seeing material delivered to Nevada Gold Mines during the second half of 2022.

Matt Gili, President and Chief Operating Officer of i-80, said: “The extensive experience and expertise brought by Hatch Ltd will be one of the crucial elements enabling i-80’s success in re-commissioning and operating Nevada’s newest refractory processing facility.”

Battery-electric, teleremote and VR tech to feature on MacLean’s MINExpo booth

The MacLean focus at MINExpo 2021 will be squarely on the latest outputs from the company’s technology development efforts in the areas of electrification, automation and digitalisation, the company has confirmed.

Show updates on September 13-15 in Las Vegas include the latest on the MacLean battery-electric product line, teleremote technology, as well as telemetry and virtual reality training technology to round out the clean, automated and data-rich design philosophy that is at the core of the company’s ‘Application Intelligence’ technology campaign, it said.

“We have been doing fit-for-purpose mobile equipment manufacturing for the past 50 years so in one sense, ‘Application Intelligence’ is simply a continuation of the MacLean value proposition to the global mining industry,” MacLean President, Kevin MacLean, says. “The only difference is the ramp up of our technology development capabilities and collaboration with producers and other OEMs, to make the underground environment safer and more productive. Understanding the mining cycle and designing solutions that fit the job is what the ‘engineering’ means in MacLean Engineering.”

Adam Howse, MacLean Business Development Manager for the Western US & Canada, said: “How far we have come already and how far we still intend to go in designing underground mining vehicles that are emissions-free and able to be highly automated in a multi-OEM environment – this is what we will be sharing first-hand with booth guests at the show.

“At the same time, this global story of the evolution of smart mining equipment is complemented by a local story for us in northern Nevada, where we established a branch in 2020 and where we continue to expand our aftermarket support capabilities for customers in the historic Elko mining camp as well as across the western US.”

The launch of the MacLean ‘Application Intelligence’ campaign includes a new corporate website that will be a hub for information about the full and expanding MacLean product line for both battery electric and diesel-powered mining vehicles.

MacLean explained: “Application Intelligence represents the potential contained within the overlap of on-vehicle technology development, mobile equipment manufacturing expertise and deep knowledge of the mining cycle. It is the driving ethos behind the electrification, automation and digitalisation efforts that continue to evolve the MacLean mining vehicle product lines that span the ground support, secondary reduction and utility vehicle categories.

“This includes the next generation of MacLean ground support installation that will include robotics engineered life underground, building on the 30-year and recent 500-production unit production milestone for the 900 Series scissor bolter product line.”

DuPont Clean Tech to provide low emission sulphuric acid plant input at Rhyolite Ridge

ioneer Ltd has awarded DuPont Clean Technologies a contract for the licence, engineering and supply of proprietary equipment for the planned sulphuric acid plant at the company’s Rhyolite Ridge lithium-boron project in Nevada, USA.

Specialty technology provider DuPont will work with engineering partner SNC-Lavalin on the plant design, providing best-in-class MECS® sulphuric acid production technology for a plant with a 3,500 t/d capacity, and controls that limit emissions to among the lowest in the world for this type of facility, ioneer says.

The DuPont contract is conditional on a final investment decision on the project by the ioneer Board of Directors, which is expected shortly.

In June, Rhyolite Ridge became the first project with planned sulphuric acid production to receive a Class II Air Quality permit in Nevada.

Employing advanced technologies, the plant will meet stringent NV Class II air quality standards and water pollution control, according to ioneer. DuPont will also supply its latest generation MECS Super GEAR™ catalyst and other critical proprietary equipment, with the plant set to convert sulphur into commercial-grade sulphuric acid, used to leach lithium and boron from the crushed rock.

The heat released in the process will be recovered to produce steam for electricity. The plant will generate an initial 35 MW of electricity, which is sufficient to power the entire Rhyolite Ridge operation and means ioneer will not draw electricity from the grid, the company says.

“Rhyolite Ridge will be an energy-independent operation, using primarily co-generated, zero-carbon power,” it added.

The heat generated will also be used for evaporation and crystallisation processes required to produce lithium carbonate and boric acid.

Once operational, Rhyolite Ridge is expected to produce 20,600 t/y of lithium carbonate, converting in year four to 22,000 t/y of battery-grade lithium hydroxide, and 174,400 t/y of boric acid. Pending final federal US Department of the Interior approval of the Plan of Operation, the project is expected to begin production in the second half of 2024.

Commenting on the contract, ioneer Managing Director, Bernard Rowe, said: “Development of the Rhyolite Ridge lithium-boron project is a critical strategic step to enable US production of lithium-ion batteries for electric vehicles and renewable energy storage. ioneer’s core commitment is to produce essential materials in an environmentally and socially responsible and sustainable manner through lowered emissions, reduced water usage and a minimal surface footprint. We are delighted to welcome MECS-DuPont to our team. It is a world-leader in clean technology and emissions control and will work alongside ioneer to deliver this tier-1 project in the US.”

Global business leader of DuPont Clean Technologies, Eli Ben-Shoshan, said: “We have worked in close partnership with ioneer and SNC-Lavalin to be able to guarantee the precise performance and emissions control ioneer needs for its Rhyolite Ridge project to meet stringent environmental standards and production objectives. We are excited to be part of a project that helps ioneer cleanly produce lithium essential to advancement of electric energy markets and to be able to support it with our many decades of expertise in sulphuric acid plant technology.”

ioneer contracts Veolia Water Technologies for Rhyolite Ridge lithium-boron project

ioneer Ltd has awarded a major engineering and equipment supply contract to Veolia Water Technologies Inc for the development of the company’s wholly-owned Rhyolite Ridge lithium-boron project in Nevada, USA.

Veolia has commenced work on final detailed engineering design of the equipment package, which includes evaporation, crystallisation and dewatering equipment. It is the largest single supply contract that ioneer will award as part of the Rhyolite Ridge build, the company said.

The contract has been awarded on a limited notice to proceed basis. Phase one, the supply of engineering services for detailed design, has commenced while phase two, the supply of equipment, is conditional on a final investment decision on the project by ioneer’s Board of Directors.

The lithium and boron resource at Rhyolite Ridge is estimated at 146.5 Mt, including a reserve of 60 Mt. The company expects to mine and process 63.8 Mt over the 26-year mine life at an average annual rate of 2.5 Mt/y.

Veolia is, ioneer says, a world leader in the design and delivery of systems for purification, recovery and drying of inorganic chemicals using HPD® evaporation and crystallisation technologies. Furthermore, Veolia provides state-of-the-art research and development capabilities to facilitate the understanding of multi-component systems and their optimisation for efficiency, operability and final product quality.

Veolia and ioneer have been working together since 2018 to demonstrate the feasibility of the process design, including design and operation of ioneer’s full simulation pilot plant in Vancouver, British Columbia. Veolia has also conducted laboratory testing and simulated key unit operations including clarification, ion exchange purification, evaporation, crystallisation and precipitation at Veolia’s Phillip J Stewart Technology Center in Plainfield, Illinois, including the production of high purity lithium hydroxide monohydrate. The results obtained from this work further confirmed the design parameters, reduced the technical risks and boosted the project economics, according to ioneer.

ioneer Managing Director, Bernard Rowe, said: “We have been working closely with Veolia over the past three years during the pilot plant and definitive feasibility study phases and have developed a strong relationship and mutual respect. Veolia is a recognised leader in process design and engineering, with direct experience in developing solutions for lithium processing facilities. Veolia’s experience and capabilities are important to meet required purity standards in our production facilities.”

CEO of Veolia Water Technologies Americas, Jim Brown, said: “Veolia, as the leader in ecological transformation, is excited to be part of ioneer’s commitment to providing the materials necessary to further develop renewable energy and clean technologies by utilising our industry experience and state-of-the-art research facility to develop this resource. Our long-term cooperation working together with ioneer has been instrumental in bringing the project to this point.”

Barrick Gold’s Artisan Z50 battery-electric trial paying off at Turquoise Ridge

Barrick Gold’s decision to carry out a three-year production trial using Artisan Z50 battery-electric vehicles at the Turquoise Ridge gold mine looks to be paying off, with underground tonnage mined at the joint venture operation increasing during the most recent quarter.

Back in November, Sandvik and Barrick confirmed the signing of a partnership agreement for trailing and enhancing battery-electric vehicles (BEVs) for underground hard-rock mining. This would see a three-year production trial take place where Sandvik would deploy four Artisan Z50 BEV trucks at the Turquoise Ridge gold mine, part of the Nevada Gold Mines joint venture where Barrick is the 61.5% owner and operator.

In the company’s just-released June quarter results, Barrick reported that Turquoise Hill gold production in the June quarter was 15% lower than the prior quarter mainly due to an extended planned maintenance shutdown at the Sage autoclave. It noted that upgrades to the autoclave during the shutdown were expected to deliver improved reliability and performance in the second half of 2021.

And, while total tonnes mined decreased 12% compared with the prior quarter – driven by lower open-pit production – underground tonnes mined improved 11% quarter-on-quarter it said.

In this three-month period, Turquoise Ridge benefitted from “efficiency gains from the Sandvik Z50 electric haulage trucks at Turquoise Ridge” and higher tonnes mined from the Vista underground after remediation efforts were completed in the March quarter of 2021 following the previously disclosed fall of ground, it said.

While the use of the Z50s benefitted tonnage mined in the quarter, Barrick did not in its follow-up quarterly presentation that it was “working with Sandvik to address ongoing issues with batteries”.

Still on Turquoise Ridge, Barrick reported that shaft sinking on the Third Shaft at the mine had advanced to its final depth of 989 m below the collar in the quarter.

Construction of the Third Shaft, which has a hoisting capacity of 5,500 t/d, continues to advance according to schedule and within budget, it noted, with commissioning in late 2022. The focus of the project is now shifting from sinking activities to equipping in the September quarter.

Together with increased hoisting capacity, the Third Shaft is expected to provide additional ventilation for underground mining operations as well as shorter material haulage distances, according to Barrick.

As at June 30, Barrick had spent $201 million (including $17 million in the June quarter) out of an estimated capital cost of around $300-$330 million (100% basis).

Thyssen Mining is carrying out the shaft sinking project at the Third Shaft.

FLSmidth set to showcase lithium engineering expertise at ioneer’s Rhyolite Ridge

ioneer Ltd has awarded a major engineering and equipment supply contract to FLSmidth for the development of the Rhyolite Ridge lithium-boron project in Nevada, USA.

The contract has been awarded on a limited notice to proceed (LNTP) basis, with the supply of the equipment packages being conditional on a final investment decision on the project by ioneer’s Board of Directors.

Under the contract, FLSmidth has commenced work on product engineering for the equipment packages, which include crushing and material handling equipment, plus lithium carbonate and boric acid dryers.

FLSmidth, Ioneer says, has significant experience in providing technology, equipment, engineering and services expertise to the battery minerals sector. It has a strong US presence and is committed to improving project efficiency while reducing environmental impacts on site.

FLSmidth has also introduced ioneer to Denmark’s Export Credit Agency (EKF) regarding potential financing options.

ioneer Managing Director, Bernard Rowe, said: “The contract with FLSmidth is one of the more significant supply packages we will award at Rhyolite Ridge and represents another step in the development of the project.

“FLSmidth is focused on providing environmentally sound engineering and technology solutions. This aligns with ioneer’s ambition to not only produce materials necessary for electric vehicles and renewable energy infrastructure, but to do so in an efficient and environmentally responsible manner through lowered emissions, significantly reduced water usage and a small surface footprint.”

FLSmidth Mining President, Mikko Keto, said: “This contract provides clear recognition of our experience, know-how, and world-class technologies for processing lithium. It is also important to note that our localised approach and strength in service and aftermarket were important factors for ioneer when it came to choosing a partner.”

The lithium and boron resource at Rhyolite Ridge is estimated at 146.5 Mt, including a reserve of 60 Mt. The company expects to mine and process 63.8 Mt over the 26-year mine life at an average annual rate of 2.5 Mt/y. This will see it produce, on average, 22,340 t of lithium carbonate (99% purity) (years 1 to 3), 21,951 t of lithium hydroxide (99.5% purity) (year four onward) and 174,378 t boric acid (life of quarry).

ioneer’s Rhyolite Ridge lithium-boron project achieves major permitting milestone

ioneer Ltd, a lithium-boron project developer, has confirmed the issuance of a Class II Air Quality Permit for its Rhyolite Ridge project in Nevada, USA.

The issuance of the Air Quality Permit follows a detailed review of the project by the State of Nevada Division of Environmental Protection Bureau of Air Pollution Control and is a requirement for construction to commence at Rhyolite Ridge.

The project will comprise a quarry, an overburden storage facility, the first sulphuric acid plant permitted in the State of Nevada, an ore processing facility responsible for boric acid and lithium carbonate production, and a spent ore storage facility.

The project’s acid plant features MECS®/SNC Lavalin designed heat recovery technology, which means the plant will generate all the electricity and heat needed for normal operations, according to ioneer. This means the operation will be energy-independent and using co-generated zero-carbon power. The acid plant features state-of-the-art controls that limit emissions to among the lowest in the world for this type of plant, the company claims.

“The facility will not use fossil fuels to generate electricity during normal operations and will not draw power from the electricity grid,” the company said.

ioneer’s Managing Director, Bernard Rowe, said: “Our commitment to responsible production is at the core of our operation. The issuance of the Class II Air Quality Permit represents a significant milestone for the Rhyolite Ridge lithium-boron project and supports our detailed plans for a processing plant with low emissions and minimal hazardous air pollutants.

“After regulatory review and public comment period, we are pleased that Rhyolite Ridge is the first project with sulphuric acid production to receive a Class II Air Quality permit in Nevada.”

He added: “As the most advanced lithium development project in the US, we are committed to ensuring Rhyolite Ridge is a sustainable, environmentally sensitive operation that also delivers significant positive economic impact in the state of Nevada. This important step allows us to continue to develop the project and work toward construction.”

The lithium and boron resource at Rhyolite Ridge is estimated at 146.5 Mt, including a reserve of 60 Mt. The company expects to mine and process 63.8 Mt over the 26-year mine life at an average annual rate of 2.5 Mt/y.

Hycroft Mining continues evaluation of novel sulphide heap oxidation/leach process

After testing out a “novel” oxidation and leaching process at the Hycroft Mine in Nevada, USA, Hycroft Mining Holding Corp is making plans to go back to a conventional oxide leaching setup in 2021.

The company produced 27,392 oz of gold and 178,836 oz of silver in 2020, an almost three-fold increase over 2019. It hit these numbers while operating at a pre-commercial scale using the novel process, which oxidises sulphides ahead of leaching.

It is now planning for run-of-mine production of 45,000-55,000 oz of gold and 400,000-450,000 oz of silver in 2021 using conventional cyanide heap leach.

It is anticipated that mining in the first four months of 2021 will be performed using the existing Hycroft fleet and a rental fleet, moving approximately 1.5 Mt/mth of ore and waste. For the remainder of the year, Hycroft intends to mine some 500,000 t of oxide and transitional ore and waste per month with a more cost-effective mining fleet.

Diane R Garrett, President & Chief Executive Officer, reflected on the results: “2020 was an important year for Hycroft as the company continued to focus on the restart of the Hycroft Mine. Throughout the year, we advanced work on the proprietary two-stage sulphide heap oxidation and leach process and made several important findings that will need to be addressed prior to our implementing the novel technology on a commercial scale.

“In 2021, we expect to mine predominantly oxide and transition material, which are more economic when treated using a conventional run-of-mine heap leaching method, which gives us the opportunity to continue to refine the operating parameters and flowsheet for the new heap leach pad and novel process. While the company continued to make significant progress in better understanding this proprietary process and its application on a commercial scale, the past year also presented some operational challenges, including learning to navigate in a newly emerged COVID-19 world.”

In the last few months, Hycroft says it has worked alongside consultants to identify and investigate opportunities for improvements in operating parameters for the two-stage sulphide heap oxidisation and leach process. The result of the work to date has identified several items that were not considered or included in the original plan and design but are critical to the success of this process. These findings include:

  • Adding a forced air injection system for the leach pad which is a key component of the oxidation process;
  • Developing a system for segregating solution flows to and from the heap leach pad to avoid co-mingling of solutions among heap lifts and ore processing stages that negatively impact recoveries and conditions on the leach pads;
  • Identifying that the finer crushed material requires agglomeration in order to achieve optimal permeability and gold/silver recoveries;
  • Understanding that higher soda ash, caustic soda, and cyanide consumption will be required which Hycroft experienced throughout the 2020 pre-commercial test pad programs and recently confirmed through the review of the test work;
  • Determining that some transitional ores are more economically attractive when processed as direct leach, run-of-mine material; and
  • Concluding that additional variability metallurgical and mineralogy studies will be required to better understand each of the geometallurgical domains in the orebody. While there was some variability work completed in the past, the recent test work has revealed that additional variability test work and compositing is necessary to fully understand the geometallurgy of each domain, and that additional sampling, including sampling below the water table where the predominance of the sulphide resources exist, is required given the complexity and variability of the large orebody.

The additional variability test work will also include detailed mineralogy studies as it is important to understand the role other minerals may play in the overall oxidation process and to enhance Hycroft’s ability to measure oxidation rates accurately and consistently, it said.

The team at Hycroft has developed an approximate $10 million program for drilling and additional metallurgical and mineralogical studies in 2021. This program of work has been approved by the Board of Directors of Hycroft and can be funded from existing cash and Hycroft’s current operating plans.

Hycroft expects to mine and stockpile at least 300,000 tons (272,155 t) of sulphide ore in 2021 that, once sufficient additional work on the novel process has been completed, will be available for testing to further refine operating parameters and measure its performance for large scale application of the oxidation heap leach.

Garrett added: “2021 is a foundational year designed to advance the work necessary in preparation for larger-scale sulphide operations. The team is working diligently to optimise current and future heap leach mine plans and to evaluate all opportunities for more profitable mine plans in the near and medium term. This work involves taking a ‘ground up’ approach working from the orebody out. The company’s prior plan was developed using a $1,200/oz gold price pit shell which leaves profitable ore behind in the current gold and silver price environment. By running pit shells at recent gold and silver prices, we have identified additional areas of oxide mineralisation that can generate cash flows over the next several years and we have already begun to identify areas of higher-grade mineralisation that will become important for mine sequencing and further improving cash flows prior to accessing sulphide material.”

As the company considers life-of-mine development and planning for the Hycroft deposit, particularly in the current gold and silver price environment, Hycroft says it is prudent to evaluate proven processing technologies for treating some ore types that may be more profitable than only using the two-stage sulphide heap oxidation and leaching process.

Potential opportunities being examined by the company in 2021 include: developing an understanding of the grade range distribution of the sulphide material; completing on-going work on the higher-grade areas of Hycroft; and following up on historical high-grade intercepts.

In order to capitalise on these potential opportunities, which take advantage of the current commodity price environment, Hycroft believes that it should also evaluate the benefits of a multi-process operation. Long-term operating scenarios may include conventional run-of-mine cyanide heap leaching for the oxide and transitional material, sulphide heap oxidation and leaching using the novel process, and an appropriately sized milling and flotation plant for processing the higher-grade ranges of sulphide material.

“The company believes that the plan it has put in place for 2021 will provide the new team the time to fully consider and evaluate these opportunities and make any necessary changes to improve the leach pads, process plants and process flowsheet, maintain and develop its workforce, and advance the project, in order to further enhance the value of the project,” it said. “As the test work advances and alternative processes are considered, the company expects to perform technical studies and trade-off evaluations which may result in an updated feasibility study.”