Tag Archives: Quebec

Autonomous haulage trials produce “favourable” results at Agnico Eagle LaRonde

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Agnico Eagle, during the June quarter, continued to test out autonomous mining at its LaRonde Zone 5 underground gold operation in Quebec, Canada, and, so far, the results have been encouraging.

The company has been increasing the network and communications capacity at the deep underground mine in the last year or so, with an LTE network now deployed in Zone 5.

The use of this advanced communications infrastructure should help facilitate the use of autonomous mining equipment at the operation, Agnico said; a theory it is currently testing out.

Agnico said, in its June quarter results, trials of automated mining equipment (two trucks and one scooptram) continued over this period, with testing taking place on weekend night shifts when underground activity is at reduced levels. Trials initially began in the December quarter of 2018.

The company said: “Testing has yielded favourable results as autonomous mucking and hauling of ore from underground to surface was successfully achieved.”

Trials are set to continue throughout this year, the company said.

RNC Minerals studying trolley assist, automation at Dumont nickel-cobalt project

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The latest feasibility study on RNC Minerals’ jointly-owned Dumont nickel-cobalt asset in Quebec, Canada, has identified the potential for both electrification and automation of the open-pit haulage fleet at the project.

The DFS, completed by Ausenco, showed that initial nickel production at Dumont could come in at 33,000 t/y, before ramping up to 50,000 t/y in a phase two expansion. This would result in some 1.2 Mt of nickel in concentrate output over the 30-year life, with an initial capital expenditure estimate of $1 billion.

This initial investment would be paid back with a $920 million after-tax net present value (NPV, 8% discount) and 15.4% post-tax internal rate of return, factoring in a nickel price of $7.75/Ib (>$17,000/t) and a US$/C$ exchange rate of 0.75, the company said.

Dumont, as envisaged in the DFS, would use conventional drilling and blasting, with loading by a combination of hydraulic excavators and electric rope shovels into trucks ranging in size from 45 t to 290 t. The process plant will be constructed in two phases. Phase one will have an initial average throughput of 52,500 t/d using a single SAG mill and two ball mills for grinding, desliming using cyclones, conventional flotation and magnetic separation, to produce a nickel concentrate also containing cobalt and PGEs. Phase two throughput will be doubled to 105,000 t/d in year seven by mirroring the first line.

Around 42 Mt of overburden will be pre-stripped prior to start-up of operations. The life-of-mine plan excavates 2,100 Mt of material, including 1,000 Mt of ore, over an open-pit life of 24 years. After open-pit operations cease in year 24, 398 Mt of stockpiled ore will remain to support continued production through year 30.

One of the noticeable changes to the previous feasibility study from 2013 was the electrification of the fleet in the mine plan.

The company, which jointly owns Dumont with Arpent Inc, currently plans to increase the electrification of Dumont by incorporating trolley assist on the planned main ramps. RNC said this will reduce cycle times, and reduce diesel consumption by over 35% (approximate reduction of 450 million litres over the life of mine), which, in turn, will cut greenhouse gas emissions by 1.2 Mt of CO2 equivalent, the company said.

And, among three “additional upside opportunities” listed in the DFS highlights was the use of haulage automation, which could potentially improve the NPV by some $75-115 million, the company estimated.

RNC said: “As autonomous equipment has been employed in open pits for over a decade and the global fleet currently approximates a combined 400 units of haul trucks and blasthole drills, automation is rapidly becoming proven technology.”

As a result, the company engaged an industry expert, Peck Tech Consulting, to assess the suitability of Dumont for automation.

“Based on Peck Tech’s prefeasibility-level assessment, the implementation of an Autonomous Haulage System could reduce the peak truck fleet by 20% and reduce site-wide all-in sustaining costs by over 3%,” RNC said.

“Further potential could be achieved with an Autonomous Drilling System (ADS),” the company added, saying it is continuing discussions with various mining equipment suppliers to understand the impacts and benefits in greater detail.

Plan Nord backs Newmont Goldcorp’s 4.0 mine vision at Éléonore gold operation

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The Government of Québec, through the Société du Plan Nord, says it will invest C$1.75 million ($1.28 million) to connect Newmont Goldcorp’s Éléonore mine facilities to the existing regional fibre optic network.

“This project will enable one of Quebec’s most innovative mining companies to continue advancing its vision to create mine 4.0, an interconnected mine of the future,” the government said, adding that the connection, which will help optimise the company’s operations, will also increase the quality of life of workers on site and encourage employee retention.

Jonatan Julien, Minister of Energy and Natural Resources and Minister responsible for the Côte-Nord region, made the announcement this week while visiting Éléonore.

As part of this project, 124 km of fibre optic cable will be laid from the Eastmain 1A link to the Éléonore mine. This project, valued at C$3.5 million, will be delivered by the non-profit organisation Eeyou Communications Network (ECN), with the new high-speed connection expected to be operational in 2020.

Julien said: “The mining sector is entering a new era with mine 4.0. Today’s funding will contribute to the Éléonore mine’s competitiveness in the future: access to a reliable and high-performance telecommunications network is fundamental for the industry to modernise. The realisation of this project is excellent news for the Eeyou Istchee James Bay region, but also for the Quebec economy.”

Sophie Bergeron, General Manager, Éléonore Mine, Newmont Goldcorp, said: “This joint investment from our Cree partner, Eeyou Communications Network, and the Société du Plan Nord will connect the mine to a fibre optic network, providing far more bandwidth than we have today, and will support our vision of creating the first 4.0 mine in Quebec.

“With this technology backbone in place, new sustainable and responsible mining developments can consolidate the leadership role Quebec plays in Canada’s mining sector and beyond.”

Éléonore was expected to produce some 360,000 oz of gold in 2018 from the underground Roberto deposit. Ore is mined from four horizons using sill and stope techniques, then processed onsite using a conventional circuit that includes crushing, grinding, gravity, flotation and cyanidation.

The operation has begun to develop a fifth mining horizon and build a production shaft, both of which will bring Éléonore closer to its full production capacity, a key part of the company’s plan to increase production by 20% by 2021.

At Éléonore, all underground workers, vehicles and other heavy equipment are outfitted with radio frequency identification tags that transmit a unique ID number via a Wi-Fi connection to the Cisco access point throughout the mine. Telemetry units integrated into vehicles also monitor the functions and systems in the vehicle’s engine, and issue an alert to mine managers when something needs attention, the company said.

The Société du Plan Nord contributes, from a sustainable development perspective, to the planning and integrated and coherent development of northern Quebec, it says. It does so in consultation with representatives of the regions and indigenous peoples, as well as the private sector.

CFPBJ bolsters training program with mining equipment simulator

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The Centre de formation professionnelle de la Baie-James (CFPBJ), in Quebec, Canada, says it has inaugurated a new mining equipment simulator as it looks to improve training facilities for its students.

The acquisition of this tool for mining sector training was made possible through initial funding for CFPBJ’s ore extraction study program, it said. In addition, the Ministère de l’Éducation et de l’Enseignement supérieur provided C$310,000 ($229,065) and the Commission des partenaires du marché du travail granted C$476,000 under the Programme partenarial pour la formation et l’innovation to purchase equipment for the program to train students in operating heavy machinery on forest roads.

The CFPBJ said: “This new state-of-the-art tool will reaffirm the CFPBJ’s position as an academic leader in specialised vocational training. Spending more hours operating equipment will greatly enhance the skills of students in programs devoted to ore extraction and heavy equipment operation on forest roads.”

Sonia Caron, Director of Services and Centre, said the centre was committed to continuously improving its training programs by ensuring they are as realistic and dynamic as possible. “Virtual reality in vocational training allows students to consolidate their learning and reach a level of development that will greatly accelerate their entry into the workforce.”

The simulator purchase will make it easier to learn how to handle heavy equipment on forest roads and operate underground mining equipment. It will also enable customised training for surface mines, the CFPBJ said.

“Multisensory simulation will allow students to test reality without the dangers of a real field operation. Students will be able to practice in all types of conditions, including unforeseen situations: punctures, mechanical breakdowns, fires, etc. In addition, complementary equipment will allow for real-time data analysis, and the simulation modules can be customised to reproduce the actual physical environment of partner mine sites,” the centre said.

Safety is also at the heart of the CFPBJ’s concerns, with Caron saying: “This simulator enhances skills needed to work safely and use the machines efficiently. The risk of accidents is considerably reduced because students have many hours of driving experience before they operate the machinery.”

The CFPBJ has been operating in the James Bay region of Quebec since 1998 offering a wide range of study programs in several industries, including mining, forestry, construction, health and administration.

Eldorado connects the Triangle and Sigma dots at Lamaque gold mine

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Eldorado Gold says it has achieved commercial production at its wholly-owned Lamaque mine in Quebec, Canada.

Lamaque produces ore from the Triangle deposit, which is then processed at the refurbished Sigma mill.

With an initial mine life of around seven years, Lamaque is planning to mine and process over 500,000 t of ore at an average grade of 7 g/t Au this year, with production expected to amount to 100,000-110,000 oz of gold (including pre-commercial production) at cash operating costs of $550-600/oz of gold sold. Output is then expected to increase to 125,000-135,000 oz of gold in 2020 and 2021.

In 2018, inferred resources at Lamaque were increased by over 50%, and further drilling is currently ongoing to increase both the reserves and resources, Eldorado said. With over 37,000 m of exploration drilling budgeted for 2019 and excess capacity at the Sigma mill, the company said it is well positioned and focused on optimising the potential of the Lamaque mine.

Eldorado’s Chief Operating Officer, Paul Skayman, said: “We are proud to announce the achievement of this important milestone just over 18 months after acquiring this asset. It is a testament to all of the hard work that has gone into the exploration, prefeasibility study, engineering and construction that we have safely delivered commercial production ahead of schedule.”

Lamaque consists of the newly-discovered Triangle gold deposit, only 2.5km south of the historical Lamaque and Sigma mines, which are also on the property and produced over 10 Moz of gold.

Granada Gold Mine brings Gekko in for “disruptive” pre-concentration tests

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Toronto-listed Granada Gold Mine thinks pre-concentration by separation has the potential to lower capital and operating costs at its Granada gold project in Rouyn-Noranda, Quebec, Canada.

The company has come to this conclusion after receiving higher grades during testwork, which, it said, “may have implications for the grade of future mill feed, the size of the gold deposit, and the costs associated with future mine production.”

The company went to Gekko Systems of Ballarat, Australia, for this testwork. Granada said of Gekko: “Their innovative pre-concentration system increases recovery values, reduces ore mass and waste, reduces water use, lowers power requirements, and improves feed rates, all potentially meaning lower capital and operating costs for Granada along with higher recovery rates.”

A 260-kg sample of low-grade drill core assaying 0.6 g/t was upgraded to 6 g/t with a 60% overall recovery by this work. The Gekko laboratory processed the sample by crushing through different size fractions, homogenised, and split according to standard lab practices, Granada said. Gravity tests were conducted on coarse and fine fractions, approximately +600 μm and -150 μm, respectively.

A grade of 21 g/t Au was achieved from the coarse size fraction, with a recovery of 40%, resulting in an upgrade ratio (concentrate/feed) of 35.

Frank Basa, Chairman and CEO of Granada Gold, said: “As a result of this preliminary work, we believe that employing disruptive technologies on lower-grade ore to pre-concentrate the mineralised material for process plant feed can be advantageous. This approach can be used to evaluate the potential to increase the gold resource and other recoverable metals which, in turn, will lower project capital and operating costs.”

In a related matter, the company has also begun a test programme using the pilot plant of its sister company, Canada Cobalt Works. In this first round of tests, a 120-kg sample of low-grade mineralised rock from the Granada gold mine waste dump was processed by screening the material into three screen sizes followed by gravity separation. These concentrates were then analysed for gold, silver, cobalt, nickel, and copper.

Gravity assay test results are pending, with a particular focus on recoverable base metals.

The current feasibility study for the on-site gold mine and plant at Granada has been put on hold pending results of the metallurgical studies. The environmental studies to install a 600 t/d gravity leach plant are, in the meantime, ongoing at the Canada Cobalt Works Castle mine. The flowsheet has been completed and equipment has been sourced, the company said.

The company is in possession of all permits required to commence the initial mining phase, known as the “Rolling Start”, which allows the company to mine up to 550 t/d, capable of producing up to 675,000 t of ore over a three-year period.

Goldcorp’s Éléonore gold mine cleans up its act with novel wastewater treatment

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The latest winner of Goldcorp’s Global Excellence Awards 2019 to be featured in its online blog is the Éléonore gold mine and a novel system that proved its worth removing ammonia and residual cyanide by-products at the company’s Éléonore gold mine in Quebec, Canada.

Goldcorp said: “For any mining operation, effective wastewater treatment to remove contaminants is an indispensable step needed to minimise environmental impacts and maintain the mine’s social license to operate.

“When elevated concentrations of ammonia and residual cyanide by-products were detected in mill effluent at Éléonore, in 2014, the mill and environmental team took decisive action by introducing a novel wastewater treatment process that rectified the problem and secured Éléonore a Global Excellence Award for Sustainability Stewardship.”

Following Éléonore’s mill start-up in 2014, the new process water bleed (discharge) to water treatment plant (WTP) and paste backfill process resulted in increased concentrations of contaminants in water effluent, according to Goldcorp.

Even though the cause of the ammonia and residual cyanide toxicity couldn’t readily be identified, the Éléonore team immediately notified all major stakeholders, such as the Quebec Environment Ministry, Environment Canada and the Cree Nation Government – Environment Committee of Opinagow Collaboration Agreement, informing them on the extent of the problem and plans to rectify the situation.

France Trépanier, Environmental Coordinator at Goldcorp, said: “From the outset, we wanted to be very open and transparent with key stakeholders on steps we were taking to identify the source of the toxicity and plans to resolve the problem. Through ongoing dialogue and regular reporting, we were able to maintain a collaborative climate and establish strong partnerships based on mutual trust.”

During 2015 and 2016, the Éléonore team developed an action plan, investigated various water treatment options, and executed a series of projects including cyanide detox and leaching circuits optimisation to reduce effluent contamination, the company said.

The team also worked on mill water balance through its zero-bleed project with the objective of reducing contaminant process water discharge to the WTP, which involved reducing fresh water consumption by replacing water-sealed pumps used in the mill with mechanical seal pumps. “These projects increased control of process water contaminant concentration but didn’t resolve toxicity issues,” Goldcorp said.

A consultant working on the toxicity problem recommended the Éléonore team consider zeolite treatment and a Moving Bed Bacteria Reactor (MBBR) system to process wastewater effluent. Zeolite is a mineral well known for its ability to absorb a variety of heavy metals and ammonia. MBBR, more commonly used for municipal water treatment, is an activated bacteria aeration system, where bacteria collected on porous plastic carriers breaks down organic matter from wastewater, according to Goldcorp.

A pilot project found that zeolite treatment removed ammonia but did not eliminate the toxicity. MBBR, on the other hand, could remove ammonia and cyanide by-products delivering non-toxic results at low water temperatures (8°C).

In Spring 2016, the Quebec government granted approval for Éléonore to expand its water treatment plant by adding MBBR treatment while continuing to reduce its process water discharge to reach a zero-bleed operation.

Construction got underway in the fall of 2016, and the MBBR treatment plant was commissioned in May 2017.

“Energy efficiency was one of the critical plant design considerations to minimise heating requirements in winter,” Goldcorp said. “The addition of a heat exchange system and an insulated water circuit ensured that process water could feed the MBBR to keep the bacteria-activated treatment as stable as possible during cold winter months. Now, at the second winter, treatment is achieved without any heating at a temperature around 5°C.”

From concept to completion, Éléonore workers were kept up to date on the project’s progress through regular on-site presentations and stakeholders informed of the mine’s plans through monthly reports, quarterly presentations and site visits, the company said.

Trépanier said: “Consistent communication really enabled us to demonstrate how serious we were about solving this problem, which was essential in helping secure support for this project among stakeholders and regulators.”

Following the MBBR ramp up, Éléonore reduced ammonia and cyanide by-product concentrations in its effluent by more than 90% and was designated 100% in compliance with water quality regulations in October 2017. Since MBBR has been in steady operation, mandatory effluent sampling frequency returned from weekly to monthly.

The Éléonore team recently shared its experience in implementing this novel water treatment technology at a symposium on mining and the environment. Since then, it has received numerous enquiries from other mining companies and have hosted site visits to demonstrate the water treatment process, according to Goldcorp.

“There was a lot of people from different departments working on this project over the last two-and-a-half years,” Trépanier said. “It’s very gratifying to be recognised both externally and by our peers at Goldcorp for a successful outcome. We’re very happy to share what we’ve learned with other mining companies to help improve the industry’s environmental performance.”

Remote operations could be the way forward at Westwood, IAMGold says

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IAMGold says it is looking to remotely-operated machinery to battle the challenging ground conditions being experienced at its Westwood underground gold mine in Quebec, Canada.

Westwood produced 28,000 oz of gold in the December quarter, 3% lower than the same period a year ago, the company said in its 2018 financial results. This was primarily due to lower head grades.

“The lower grades reflected mining activity that sequenced through lower-grade stopes as part of the mine plan. Head grade, excluding marginal ore, for the fourth (December) quarter and year ended 2018 was 6.78 g/t Au and 7.16 g/t Au, respectively (2017: 8.01 g/t Au and 7.8 g/t Au),” IAMGold said.

Underground development for the year ended 2018 was 10,600 m, averaging 29 m/d and comprised of 10,100 m of lateral development and 500 m of vertical development, according to the company. Underground development continued in the December quarter to open up access to new mining areas with lateral development of approximately 2,500 m, averaging 27 m/d.

The company said: “During the quarter, development continued to focus on the ramp breakthrough on level 132, while respecting safety protocols in place for mining in areas where seismicity is present.”

In line with these safety protocols, three units of bolting equipment designed to manage seismic exposure were received during the December quarter, IAMGold said.

The company said it expects production at Westwood in 2019 to be in the range of 100,000-120,000 oz as mining and development activities continue to progress.

Yet, in maintaining the company’s safety protocols at the underground operation, IAMGold said it was expecting to commission additional equipment at Westwood, in 2019, capable of operating “remotely in areas with challenging ground conditions”.

IAMGold is currently working on reviewing the mine plan at Westwood, its only underground operation, and expects to publish updated development guidance in the December quarter.

Newtrax helps haulage operations at Glencore’s Matagami zinc-copper mine

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Newtrax says its Mobile Equipment Telemetry (MET) system has helped Glencore raise productivity and increase operational awareness at its Matagami zinc-copper underground mine in Quebec, Canada.

The operation, which mines the Bracemac and McLeod deposits, first installed the MET system back in 2016 on trucks and LHDs in order to maximise its haulage efficiency. It has ended up doing much more, according to a case study from Newtrax.

Newtrax said: “Glencore Matagami mine has been faced with a continual challenge: how to haul ore to the surface most efficiently. Normally, this isn’t the most difficult challenge a mine faces but, at Matagami, all their ore is hauled with trucks.

“Efficiency is vital at the mine because those haulage trips are more than 8 km in each direction. The huge distance means it’s essential to get every tonne possible onto the truck before it heads to the surface.”

As part of its overall haulage efficiency aim, Glencore needed more information about its operation, Newtrax said – enter Newtrax and MET.

MET solutions provide mine operators with essential information and indisputable data pulled directly from mining equipment, according to Newtrax. “The ability to access this data empowers mining companies to understand the precise manner in which their machines are being used, how well each individual machine is functioning, and can offer predictive suggestions to increase both productivity and profit,” the company said.

“The MET works with all equipment brands and models, and was easily integrated to Matagami mine’s mixed fleet of trucks and LHDs,” Newtrax added.

Glencore Matagami mine used the system in multiple ways, including to monitor the standard production times of equipment; to calculate utilisation of ore haulage; to calculate overall equipment effectiveness (OEE), and; to calculate loads per cycle.

Christian Ngoma, Underground Operations Superintendent of Matagami, said Newtrax technology allowed mine management to get a clearer idea of what is actually going on, thanks to hard data.

“The Newtrax system enables us, from a managerial perspective, to make decisions based on facts that are measurable, instead of perceptions,” he said.

Glencore Matagami installed a custom fit Payload Monitoring System, which interfaces directly with the OEM’s existing sensor network. This, according to Newtrax, enables:

  • Real-time payload data available on the Newtrax Scoreboards and cab display for the operators, and;
  • Real-time payload broadcasted to the Newtrax MET telemetry recorder every five seconds, with no operator intervention.

Ngoma said: “We now have production trucks equipped with Newtrax scoreboards to show tonnage, and the LHD operators use this tool to load the trucks in an optimal way. We now noticed that four out of five of our trucks have an average tonnage of approximately 60 t in comparison to 55 t before.

“The impact of that technology is to optimise the loading of trucks. Especially with the long haulage distance, that is our biggest challenge here.”

Since implementing the solution, Glencore Matagami has been able to raise its average tonnage from 55 t to 60 t, which has increased productivity; especially given the long haulage distances the operation is facing.

Trucks currently travel 8 km on an average cycle, but there is a possible extension to 10.4 km in the coming years, Ngoma said.

After using the Newtrax MET system for one year, the Glencore Matagami team observed the following results, according to Newtrax:

  • Five to six per cent increase in utilisation on ore haulage;
  • Four per cent increase on the OEE, and;
  • Five per cent increase on loads per cycle.

Glencore Matagami Haulage Team Supervisor, Dany Lavoie-Mercier, said: “The standard production time report is an improvement that is more representative of our daily operations. From personal experience, after having presented it to my team, I presented it again the following shift and there was a clear difference in our operations. Everything was optimised from one shift to the next.”

Solutions provided by Newtrax can be used across a number of platforms and systems, allowing for easy adaptability, the company said.

Mohammed Lamine-Lamrani, Reliability Engineer at Matagami, said: “The Newtrax system enables us to transfer data via different networks, which facilitates its adoption into different mines. The system helped us identify the different delays of activities, in terms of our machines, which allowed us to intervene, improve, and increase our OEE.”

Matagami Mine General Manager, Mark Furlotte, said digitalising the operation is part of the company’s plan for keeping the mine looking to the future.

“At Glencore, and Matagami mine, we really want to continue investing on our people, our infrastructure, and our assets. And one of the areas we want to continue investing in is technology,” Furlotte said. “We want to take things that are done elsewhere in the industry – things that are done in open-pit mines – and really bring that underground. We really want to be considered as one of the innovative mines around not only Quebec, Canada, but also the world.”

Photos courtesy of Newtrax

Eldorado Gold to continue heap leaching operations at Kisladag

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Eldorado Gold has decided to resume mining, crushing, stacking and heap leaching at its Kisladag gold mine, in Turkey, and suspended plans to build a $500 million processing plant.

The decision comes following the receipt of metallurgical test work on material placed on the heap leach pad last year.

Not only will this move defer a significant amount of capital expenditure for the company, it is also expected to help production rise to 390,000-420,000 oz in 2019, compared with 349,147 oz in 2018, a year when Eldorado suspended mining operations at Kisladag due to lower than expected gold recoveries.

Eldorado’s President and CEO, George Burns, said: “The decision to restart mining and heap leaching at Kisladag is supported by improved heap leach recoveries and confirmed by a revised heap leaching plan developed in early 2019. The revised heap leaching plan results in favourable economics when compared to milling, without the risks associated with the construction and financing of a $500 million project.”

On October 23, 2017, the company provided an update on Kisladag operations based on laboratory testwork undertaken during the September quarter of that year, which indicated that lower recoveries were expected from the zone of mineralisation located around the base of the open pit where mining was underway.

Based on available information, in the March quarter 2018, Eldorado elected to suspend mining in order to evaluate processing options. Following a year of engineering and testwork, in October 2018 the company announced that the Board of Directors had approved the advancement of a mill project. Subsequent to that announcement, gold recovery from the leach pad increasingly exceeded expectations. The company then focused testwork and analysis on the viability of resuming mining and heap leaching at Kisladag.

In parallel to mill engineering and analysis, testwork to extract maximum value from material already placed on the heap leach pad and the remaining reserves was ongoing throughout 2018.

Approximately 900,000 t of ore was placed on an inter-lift lined test pad in the March quarter of 2018. Late in the year, results from this pad were showing recoveries of approximately 58% from an extended leach cycle approaching 250 days (compared with around 40% recoveries from the original 90-day column tests).

In early 2019, the company analysed the new data and developed revised heap leaching plans, showing improved economics for the heap leaching scenario, hence the recent decision.

Eldorado said mining was expected to recommence by the end of this quarter, with the three-year guidance of 145,000-165,000 oz (2019), 240,000-260,000 oz (2020) and 75,000-95,000 oz (2021) based on mining and stacking an initial 22 Mt of ore grading over 1.1 g/t over this period, as well as continuing to leach the material currently on the pad.

This would help overall group production go to 390,000-420,000 oz in 2019, 520,000-550,000 oz in 2020 and 350,000-380,000 oz in 2021.

Eldorado said on Kisladag: “While the mill project has been suspended, the project remains viable in the short-term. The viability of the mill project will continue to be assessed in light of the results from ongoing heap leach metallurgical testwork on deeper material and in view of other investment opportunities within the portfolio,” the company said.

The other piece of exciting news within the company’s results was developments at its Lamaque mine in Quebec, Canada.

The company poured first gold from the Sigma mill at Lamaque in December and, in the March quarter, the mine is expected to declare commercial production. This should set the operation up to produce 100,000-110,000 oz of gold in 2019 from the mining and processing of over 500,000 t of ore at an average grade of 7 g/t Au.

Burns said: “At Lamaque, we are very pleased with the performance of our project team who delivered the first gold pour from the Sigma mill in less than 18 months since acquisition.”

In addition, exploration success at Lamaque – which includes significant resource conversion in the C5 orebody, in particular – has led the company to review options to increase throughput at the Sigma mill.

Eldorado said: “The mill has a refurbished nameplate capacity of 2,200 t/d and the potential to expand to its former capacity of 5,000 t/d with a purchase and installation of a SAG mill. Based on planned drilling and the potential conversion of inferred resources in C4, C5 and C6, the company expects to explore options to increase mill feed.”

The Lamaque underground mine is currently expected to produce 125,000-135,000 oz of gold in both 2020 and 2021.