Tag Archives: GR Engineering Services

Condor Gold looks to GRES’ Hanlon for SAG mill advice at La India

Condor Gold says it has selected Hanlon Engineering & Associates to develop a feasibility study level design for a new processing plant built around its recently acquired SAG mill at the La India gold project in Nicaragua.

A wholly owned subsidiary company of GR Engineering Services Limited (GRES), Hanlon is based in Tucson, Arizona. As lead engineer for this study, Hanlon will be responsible for the engineering designs, the capital cost and operating costs of the processing plant to a FS level of design.

Condor, earlier this year, entered into an agreement to purchase a completely new Metso Outotec SAG mill package from First Majestic Silver to serve La India.

The feasibility study design will develop costs to a +/- 15% level of accuracy for the design, capital expenditure and operating expenditure of a fully engineered processing plant package, which is normally a mandatory requirement of debt financing. The processing plant will be designed to a nominal capacity of 2,300 t/d, but have the built-in capacity in several key areas to potentially upgrade throughput to 2,850 t/d. At the 2,300 t/d rate, initial production is expected to be 80,000-100,000 oz/y of gold.

Hanlon is due to deliver the FS level engineering designs for a new processing plant within 12 weeks, working in conjunction with its GRES and using their extensive global experience with the design, construction and expansion of gold processing plants.

Mark Child, Chairman and CEO, said Hanlon Engineering was previously engaged by First Majestic Silver, the vendor of the SAG mill, to help design the new SAG mill recently purchased by Condor.

“Their knowledge of the SAG mill and involvement with many similar process plant designs completed to date will help fast track the delivery of the feasibility study design,” he said.

Abra project heads for first lead-silver production in 2023

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

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

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

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

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

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

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

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

Pantoro enlists GR Engineering to build Norseman gold processing plant

Pantoro Ltd has signed a Letter of Intent with GR Engineering Services that is likely to see the ASX-listed contractor take on the engineering, procurement and construction works for the processing facility at the Norseman gold project in Western Australia.

The gold company, which owns 50% of the asset, said detailed engineering works will commence immediately and orders will be placed for long lead items including the 3.3 MW ball mill. Contract documentation is being finalised and is expected to be executed before the end of February.

The contract value is around A$57 million ($44 million) and will be awarded as a guaranteed maximum price agreement, Pantoro noted. This value is inclusive of the crushing circuit associated with the plant.

The DFS announced in October 2020 contemplated a build-own-operate-transfer (BOOT) arrangement for the crusher at Norseman with the transfer planned in year three.

This study also outlined average production of 108,000 oz/y over a seven-year phase one life, peaking at 119,000 oz in year two of production. It also provided for a processing plant capacity of 1 Mt/y with flexibility to expand to 1.5 Mt/y.

Separately, demolition works for the existing plant on site have been awarded with commencement of site works planned for mid-February.

Pantoro Managing Director, Paul Cmrlec, said: “We are pleased that GR Engineering Services will undertake work with their proven track record in new processing plant builds in recent years. GR Engineering has been the dominant supplier of new processing plant builds in Western Australia in recent times, and we look forward to drawing on their experience in construction of the plant at Norseman.”

Ora Banda Mining hits its stride at Davyhurst Gold Process Plant

Ora Banda Mining Ltd is pleased to advise that the Davyhurst Gold Process Plant, in Western Australia, has been successfully recommissioned, with the first gold poured on February 7.

All supporting infrastructure required to sustain ongoing processing activities at the processing plant’s rated capacity of 1.2 Mt/y is now in place and has been commissioned, the company said.

This includes the new 8.25 MW gas and diesel fired power station, extensively upgraded and commissioned bore fields (for both potable and process water supply), process plant chemical storage facilities, upgraded road infrastructure for ore supply routes and an upgraded 172 room camp at Davyhurst.

Practical completion for the remedial work program undertaken by GR Engineering Services was achieved on January 24, 2021, following which a commissioning blend of low-grade oxide and transitional ore stock together with primary ore from the Golden Eagle underground deposit was introduced into the plant.

Processing operations are currently stable and running at a throughput rate approaching 1 Mt/y with targeted grind size of P80 – 106 µ being achieved. Throughput will continue to ramp in line with the definitive feasibility study (DFS) schedule. This DFS outlined a production target of 418,000 oz of gold over an initial five-year mine life based on an ore reserve of 460,000 oz (6.1 Mt at 2.4 g/t Au) from six deposits within 50 km of the existing 1.2 Mt/y plant.

The company says it is well placed to progress process circuit optimisation and production ramp up with in excess of 200,000 t of run of mine stocks currently available for processing.

Ora Banda Managing Director, David Quinlivan, said: “Yesterday’s gold pour marks a significant milestone for Ora Banda – our transition from developer to producer. We are pleased to reach this important milestone and congratulate all who have been involved on the accomplishment. It has been an impressive team effort to deliver this project into production under the uniquely challenging circumstances of 2020 and 2021.

“Our focus now remains on the continued ramp up of activity as we progress toward steady state and the ultimate goal of delivering a long-life and sustainable gold operation.”

RUC Cementation, GR Engineering plan to collaborate on Tanami Expansion work

RUC Cementation Mining Contractors and GR Engineering Services have agreed to team up as part of a plan to construct surface infrastructure, as well as complete the shaft lining and equipping for a proposed hoisting shaft at the Newmont-owned Tanami Expansion 2 project in the Northern Territory of Australia.

Today, Barry Upton (right), Managing Director of RUC Cementation Mining Contractors, and Geoff Jones (left, next to Rod Schier, Engineering Manager for GR Engineering), Managing Director of GR Engineering Services, signed this “Teaming Agreement”.

The surface infrastructure component the two plan to work on includes winders, headframe and surface conveyors.

The companies said: “Both companies have worked together to submit a competitive and technically strong offer for the works and look forward hopefully to an award in the near future.”

RUC added: “Whilst a departure from the traditional GR Engineering work scope of treatment plant construction, RUC Mining is very pleased to have GR on board as a key construction partner and values the excellence in construction that GRES bring.”

The Tanami Expansion 2 project is expected to increase the annual capacity of the processing site to 3.5 Mt/y, from 2.6 Mt/y, and extend the life of the mine beyond 2040.

Boss looks for opex, production boost at Honeymoon uranium project with NIMCIX transition

Boss Resources has announced plans to evaluate the replacement of the existing solvent extraction (SX) columns on the Honeymoon uranium mine site, in South Australia, with new NIMCIX columns.

Initial results from test work indicate the potential for this to increase production profile and reduce operating costs for the project, Boss said.

The NIMCIX contactor is a continuous ion exchange (IX) column developed by Mintek (then the National Institute for Metallurgy – NIM) during the uranium boom of the 1970s and 1980s. A notable breakthrough, it enabled uranium to be recovered from unclarified solutions, according to Mintek.

Following a January 2020 feasibility study on Honeymoon, the company has embarked on technical optimisation studies which included completing NIMCIX IX process detail design and testing. In August, cost saving results from a GR Engineering review relating to reduced site power demand and transmission line upgrade costs were announced.

These savings, along with the NIMCIX results have incentivised Boss to initiate an Enhanced Feasibility Study (EFS) to incorporate the potentially significant enhancements identified, it said.

Boss’s restart and expansion plans have been split into separate stages, of which Stage 1 and 2 are presented as the base case for the Honeymoon feasibility study, showing that production can recommence within a 12-month period. Stage 1 development focused on the restart of the existing SX plant, which has a nameplate capacity of 880,000 lb/y U3O8-equivalent. Stage 2 is an expansion strategy that will increase production to 2 Mlb/y U3O8-equivalent and involves the construction of a new IX circuit.

Additional work has now been completed by Boss, ANSTO and GR Engineering examining the potential to replace the existing SX columns on site with new NIMCIX columns.

Boss said: “The results show that it is entirely possible to eliminate the envisaged Stage 1 and incorporate a NIMCIX system with the following stipulations:

  • “The flow rate through the new NIMCIX columns must be equivalent to or higher than the SX system;
  • “The lead time to commissioning should not be significantly impacted;
  • “The overall project capital expenditure intensity should not be impacted; and
  • “As much of the current SX structural and process infrastructure as possible to be re-used.”

The conclusion of this review is that these criteria are achievable and highlighted the potential for lower unit operating cost and higher production rates over the life of mine, according to Boss.

Additional potential benefits of the conversion include:

  • Significantly higher throughput through the plant during Stage 1 and beyond;
  • Improved safety outcomes through the elimination of combustible solvents in process;
  • Improved environmental outcomes through elimination of the potential for organic entrainment to the wellfield; and
  • Simplification of the process through standardisation of uranium extraction technology.

“The company now plans to incorporate both the IX Process Optimisations announced previously and the pure NIMCIX adoption into an EFS level estimate for the Honeymoon uranium project restart to assess the economic impacts of these changes,” it said.

It has re-engaged GR Engineering Services as the engineering and lead study consultant for its EFS leveraging on the recently completed feasibility study completed in January 2020.

“Through the EFS, Boss aspires to increase the ramp up production schedule and nameplate capacity of Honeymoon through the adoption of a wholly IX (NIMCIX) system with the first stage of production ramp up delivered within the original 12-month delivery timeline from an investment decision,” it said.

Macmahon, GR Engineering on board Calidus Resources’ Warrawoona gold project

Calidus Resources has started construction ahead of schedule at its Warrawoona project, as well as made two key appointments to deliver on its gold mine development in Western Australia.

It has appointed Macmahon Holdings as the preferred mining contractor for the project, while GR Engineering Services has been awarded preferred tenderer status for the process plant engineering procurement and construction.

While construction activity has already commenced ahead of the main project construction activities, which are expected to kick off in the March quarter of 2021, these contract tenders will allow finalisation of major contracts as part of the ongoing feasibility study at Warrawoona, due for completion this month, Calidus said. It will also help facilitate front end engineering and design for the project and the placing of orders for long lead items.

This project involves the development of a new open-pit mine in the Pilbara region, with the scope of work for Macmahon to include all open-pit mining activities, and potentially some early stage civil works.

Macmahon estimates the open-pit mining work will generate around A$220 million ($160 million) in revenue over 54 months and require capital expenditure of circa-A$30 million. There is also potential for the Warrawoona project to include underground mining, which could represent a further opportunity for Macmahon when this is developed, it said.

Macmahon expects it will start work on site in the first half of 2021, with the project to eventually employ more than 120 of its personnel.

GR Engineering, which has completed the last two gold plants in Western Australia, according to Calidus, will work on the design and construction of the process plant and associated infrastructure, meanwhile.

A prefeasibility study on Warrawoona completed in July 2019 outlined average gold production of 97,000 oz/y at an all-in sustaining cost of $1,159/oz over an initial six-year mine life via a 2 Mt/y conventional CIL processing circuit with single stage crush and SAG mill.

Among the initial works the company has started are 7 km-long access road to the village and process plant (pictured); the installation of the 240 room village that has been previously purchased by Calidus; the installation and operation of communications by Telstra; and the installation and equipping of water bores.

GR Engineering comes up with cost savings at Boss’ Honeymoon uranium project

GR Engineering Services has reviewed the latest technical optimisation studies related to the restart of the Honeymoon uranium mine, in South Australia, and come up with capital expenditure savings of $6.3 million for owner Boss Resources.

Following the release of the feasibility study in January 2020, Boss embarked on technical optimisation studies which included completion of an identified ion exchange (IX) process detail design and testing, undertaken with the Australian Nuclear Science and Technology Organisation (ANSTO).

The January feasibility study highlighted a capital expenditure of $63.2 million (excluding offsite power provider upgrades) to build the two-stage mine. Stage 1 consisted of refurbishing the existing solvent extraction plant with process improvement to a capacity of 880,000 Ib/y of U308 equivalent, while Stage 2 involved adding an IX circuit to achieve annual production of 2 Mlb/y. This also estimated an average all-in cost of $32.3/lb U308 over the life of mine.

The IX process optimisation program with ANSTO aimed to remove the requirement for solution heating in the elution of uranium from the IX resin. Power input to the elution process necessitated upgrades to the transmission line to service Honeymoon with grid power from Broken Hill, 80 km southeast of the mine.

Boss devised a series of tests in consultation with ANSTO to study the effect of ambient temperature on both the conversion and elution performance, with the conversion work indicating an ambient temperature process could achieve the required conversion performance within the timeframe in the process design.

Furthermore, a 45% reduction in reagent concentration in the conversion process had a negligible effect on conversion performance and offered significant reagent savings, Boss noted.

Test work on the elution process was also successful, the company said. “While there is a small difference in the eluant requirement to achieve complete elution of the resin, there is sufficient capacity in the elution circuit as designed to achieve this without impacting the downstream processes, while facilitating significant energy savings,” it explained.

The remainder of the program aimed to provide additional information to allow detailed equipment design for IX adsorption and elution processes. As a result of this work, Boss made additional changes to the resin sulphation and regeneration processes, which could represent additional cost savings.

Boss commissioned GR Engineering to evaluate the cost implications of the above work on the feasibility study results, initially on a +/- 25% basis, with initial results confirming a capital expenditure reduction of $6.3 million owing to the reduction in heating and insulation requirements for the elution circuit and reagent make up systems, and the reduced transmission line upgrade costs.

Additionally, the engineering company identified the reduction in electricity costs alone represented an operating cost saving of $2.4 million/y, equating to $1.22/lb U308 equivalent.

GR Engineering is now undertaking an evaluation of the operating cost implications of these changes in Stage 2 operations over the life of the overall operation considered in the feasibility study.

“Boss designed the feasibility study to fast-track production from Honeymoon’s existing solvent extraction plant within a 12-month period, following a decision to mine, to capitalise on any improved market fundamentals,” the company said.

It plans to increase production to 2 Mlb/y U308 equivalent through the addition of the IX plant, which will take around 20 months to design, construct and commission.

Boss Resources Managing Director and CEO, Duncan Craib, said: “Boss continues to work on opportunities to optimise Honeymoon as a first-mover uranium restart operation – this outstanding IX test work result is one example.

“We will continue working towards net present value accretive technical advancements and revising estimates contained within the January 2020 feasibility study, strengthening Honeymoon’s potential to be one of the lowest cost uranium producers globally.”

Following these initial results, Boss plans to incorporate these optimisations into a revised feasibility study level estimate for the Honeymoon restart which will also incorporate other initiatives including the conversion of the current solvent extraction infrastructure to a NIMCIX IX system, Boss said.

In parallel, Boss’s exploration team is completing a comprehensive desktop review of the extensive historical exploration database information to define new uranium exploration targets.

“With financial support from the South Australian government to utilise innovative uranium geophysical exploration techniques, exploration is focusing on expansions to known uranium discoveries to increase Honeymoon’s production profile distal to existing JORC mineral resources (total 71.6 Mlb U308),” the company said.

It is envisaged that these new mineralised target areas will form the basis of a study to assess and define Stage 3 production ramp up to produce more than 3 Mlb/y U308 equivalent, Boss said.

GR Engineering to turn the lights back on at Davyhurst gold processing plant

GR Engineering Services has been awarded an engineering, procurement and construction (EPC) contract with Ora Banda Mining associated with the restart of the existing Davyhurst gold processing plant, in Western Australia.

The EPC contract price is A$10.8 million ($7.6 million) and will be undertaken on a fixed price basis, which includes a provisional sum component.

The scope of works include the refurbishment, optimisation and recommissioning of the existing 1.2 Mt/y processing plant, borefields and associated infrastructure. Work will start immediately and is expected to be completed in the March quarter, GR Engineering said.

GR Engineering Managing Director, Geoff Jones, said: “We are excited to be working with Ora Banda’s management team and look forward to Ora Banda becoming Australia’s newest gold producer.”

Ora Banda’s definitive feasibility study for the Davyhurst Restart project outlined a production target of 418,000 oz of gold over an initial five-year mine life based on an ore reserve of 460,000 oz (6.1 Mt at 2.4 g/t Au) from six deposits within 50 km of the existing plant.

A conventional gold three stage crushing circuit followed by a carbon in pulp processing plant will produce gold doré bars, according to Ora Banda, which hopes to commence mining in the December quarter and pour first gold in the March quarter.

GR Engineering awarded with Abra EPC contract

GR Engineering Services has been awarded a conditional engineering, procurement and construction (EPC) contract to deliver a 1.2 Mt/y lead sulphide flotation process plant and ancillary infrastructure for Galena Mining’s Abra Base Metals project in Western Australia.

The award, worth some A$74 million ($50 million), follows work carried out by the ASX-listed engineering company on the feasibility study and at the preliminary design stage of Abra.

The work will be undertaken on a guaranteed maximum price basis, according to GR Engineering, which confirmed that the contract remained subject to GR Engineering being issued with a full notice to proceed. This is dependent on Abra Mining Pty, Galena’s operating subsidiary, achieving financial close on its proposed project financing facilities. Galena, which owns 86.16% of the project through Abra, has said it will require A$170 million of pre-development capex to get the mine up and running.

GR Engineering has already commenced early engineering works up to an agreed capped amount, it said.

Geoff Jones, Managing Director of GR Engineering, said: “We are pleased to have been awarded the contract for the delivery of the Abra Base Metals project, which has followed GR Engineering’s involvement to date in the project’s feasibility study and preliminary design work.”

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

Earlier this month, the construction of the Abra box cut commenced (pictured).