Tag Archives: GR Engineering

Peel Mining’s South Cobar preliminary flowsheet to factor in ore sorting

Peel Mining says positive results from ore sorting test work at the Southern Nights and Mallee Bull deposits, part of its 100%-owned South Cobar Project, in western New South Wales, Australia, provide encouragement for the inclusion of this pre-concentration technology into future process plant design.

So encouraged by this testing is Peel that it has engaged GR Engineering to integrate ore sorting technology into an updated processing plant technical report for the project.

At the same time as this, Peel announced that GR Engineering had recently completed a preliminary process plant technical report for South Cobar that considers crushing, grinding, gravity, flotation and cyanidation process stages for the recovery of gold, silver, copper, lead and zinc from the various mineralisation styles within Peel’s deposits.

Meanwhile, the recently received positive preliminary ore sorting test work results from work undertaken on diamond drilling samples shows there is potential for improvements in the flowsheet.

The ore sorting test work, completed in conjunction with ongoing metallurgical studies, was undertaken by Steinert and TOMRA.

Steinert ’s test work on Southern Nights mineralisation demonstrated strong recovery and upgrade potential with two size range samples returning, on average, circa-93% Zn, circa-91% Pb, circa-91% Ag, circa-87% Cu and circa-82% Au recoveries to an average of circa-54% of the feed mass (circa-46% of feed mass rejection) increasing the lead and zinc grades by 61% and 64%, respectively.

TOMRA’s test work on Mallee Bull mineralisation achieved significant waste mass reductions while maintaining very high copper recoveries (≥95% for the higher-grade breccia copper and massive sulphide copper samples), the company said. A lower grade breccia copper sample upgraded from 0.59% Cu to 1.05% Cu with 77% Cu recovery and 56% mass rejection, it noted.

“Positive results from ore sorting at Southern Nights and Mallee Bull deposits provide encouragement for the inclusion of this pre-concentration technology into future process plant design and, as a result, Peel has engaged GR Engineering to integrate ore sorting technology into an updated processing plant technical report,” the company said.

Peel’s Executive Director of Mining, Jim Simpson, said: “The completion of the processing plant technical report by mineral processing solutions experts GR Engineering is a critical first step in understanding the potential composition of the milling infrastructure required for the company’s development plans.

“The detail presented in the report by GR is impressive and the report will form the basis for ongoing preliminary studies for the refinement and improvement of the processing plant design as new information comes to hand.

“We are also very pleased with the potential of ore sorting as part of any future South Cobar project hub’s processing route with initial test work pointing to the amenability of both Southern Nights and Mallee Bull mineralisation to separation using 3D-XRT ore-sorting technology, allowing for the simultaneous rejection of barren or waste material whilst retaining the bulk of contained metal, and in the process, upgrading the value of the ore.”

Simpson added: “Apart from reducing the overall feed mass by the rejection of waste at early stage, other benefits of ore sorting include potentially upgrading lower-grade mineralisation and reducing the size of the processing plant offering potentially reduced capital, power, water and tailings storage needs.”

GR Engineering to refurbish Nullagine gold mill in Western Australia

GR Engineering Services has been awarded a contract for the engineering, procurement and construction works associated with the Nullagine Mill Refurbishment project, in Western Australia.

The contract, awarded by Millennium Minerals Ltd, a subsidiary of Novo Resources Corp, is worth A$8.3 million ($5.9 million) and will be undertaken on a reimbursable cost basis, GR Engineering said.

Millennium’s mine and processing plant were shut down in December 2019 and Novo is planning to restart the processing plant in early 2021. The scope of works includes the refurbishment and upgrade of the gravity circuit and associated facilities to enable operations to recommence.

Novo said: “GR Engineering Services are synonymous with gold plant construction and refurbishment throughout Australia and were selected based upon their experience and capacity to undertake these works safely, efficiently and cost effectively.”

GR Engineering’s Managing Director, Geoff Jones, said: “GR Engineering is pleased to have been awarded the contract for the Nullagine Mill Refurbishment project. We are looking forward to working with the Novo management team to successfully and safely deliver this project.”

Full speed ahead for Wiluna Mining sulphide gold project

Wiluna Mining’s board has approved the staged development of its sulphide project at the Wiluna gold operation in Western Australia, enlisting GR Engineering Services to build the 750,000 t/y concentrator required to process the ore.

The development will see the company transition from its current production profile of producing 62,000 oz/y from mining free milling ore through the current 2.1 Mt/y carbon-in-leach processing facility, initially producing 100,000-120,000 oz/y of gold and gold in concentrate.

This will be implemented using the current, recently refurbished crushing circuit, the previously expanded mill circuit and a new 750,000 t/y concentrator by October 2021, the company said. This forms Stage 1 of the project. Wiluna then intends to increase production of gold and gold in concentrate by, at a minimum, doubling the mining rate and the concentrator to produce circa-250,000 oz/y by the end of 2023/early 2024. This is Stage 2.

Of the A$81 million ($58 million) capital cost estimate of the sulphide project, of which around A$20 million has already been committed, the concentrator is expected to cost A$26 million, pre-production underground mine activities/infrastructure development is estimated at A$37 million, drilling comes in at A$9 million and the feasibility study had a A$2 million price tag. A 10% contingency of A$7 million was also calculated.

Wiluna said Murray Engineering has been contracted to supply and maintain mine fleet for current production associated development and stoping, while Byrnecut Contractors have been engaged to provide equipment and personnel for existing development rehabilitation and new development for resource-reserve drill out programs and production from new mine areas.

To complement the current equipment and development work, the first development crew from Byrnecut is expected to be mobilised in the December quarter with further development crews to be mobilised during June 2021 to maintain the required work program, the company said.

GR Engineering has been appointed as the engineering, procurement and construction contractor by Wiluna for Stage 1 works relating to the concentrator development, the engineering firm said, adding that it expects to commence work in early December with commissioning scheduled for October 2021.

GR Engineering to build paste plant at Saracen’s Thunderbox operation

GR Engineering Services has been awarded additional work by Saracen Mineral Holdings at the Thunderbox and Carosue Dam gold operations in Western Australia.

The contract additions, which have a combined value of A$29 million ($19.9 million), include an engineering, procurement and construction contract for the Thunderbox Paste Plant project and an approved variation of the Carosue Dam Operations Plant Expansion project.

The Thunderbox paste plant work will involve the design, supply installation and commissioning of a new 150 m3/h paste backfill plant at Thunderbox. The project includes work at the existing Thunderbox operations’ (pictured) processing facility along with works at a new remote paste plant location. The contract price is A$22 million. GR Engineering says work will start immediately and is expected to complete in the first half of 2021.

At Carosue Dam, meanwhile, GR Engineering has been awarded a variation under the existing contract to install a paste pump at the Karari Paste Plant to distribute paste to the Whirling Dervish underground mine. The value of the variation is A$7 million.

These additions come on the back of being awarded a contract to carry out the engineering design, procurement and construction of expansion works on Saracen’s mineral processing plant at Carosue Dam, in November.

GR Engineering’s Managing Director, Geoff Jones, said: “GR Engineering has now worked with Saracen on three key projects in the last two years and we look forward to continuing our strong working relationship with one of Australia’s leading gold producers.”

GR Engineering set to revamp tailings leaching process at Silver Lake’s Deflector

GR Engineering Services says it has received a letter of intent from a subsidiary of Silver Lake Resources for the award of upgrade works involving the flotation tailings leach process at the Deflector gold-copper operations in Western Australia.

The project is located in the southern Murchison region of Western Australia, 450 km north of Perth and 160 km east of Geraldton.

Silver Lake previously said it planned to upgrade process infrastructure at Deflector to include a carbon-in-pulp circuit to broaden available ore sources and enhance recoveries, providing potential upside to current production levels.

The contract sum is A$23 million ($16 million) and will be undertaken on an engineering, procurement and construction (EPC) basis, the company said, adding that the contract for the works will be finalised next month and GR Engineering will commence early works immediately.

Geoff Jones, GR Engineering Managing Director, said: “This letter of intent award represents GR Engineering’s first major project with Silver Lake. We are looking forward to engaging closely with the Silver Lake team to deliver safe and successful outcomes for the project.”

GR Engineering and Salt Lake Potash to bring Lake Way SOP project to fruition

GR Engineering Services has been engaged by Salt Lake Potash to help design and construct its Lake Way sulphate of potash (SOP) project in Western Australia.

Lake Way is a 245,000 t/y SOP development with an expected mine life of over 20 years. Located in the Goldfields region of Western Australia, first production is expected by the end of the year.

GR Engineering is to provide services for non-process engineering design and the management of procurement, construction and commissioning of the Lake Way project processing facility and associated infrastructure, it said. The engineering firm has separately been engaged to undertake the civil, structural, mechanical, electrical and piping construction works for those project areas.

It is anticipated that aggregate revenue from the delivery of services, procurement and construction works associated with the Lake Way project from the commencement date to practical completion will be approximately A$107 million ($73 million), the company said.

“GR Engineering’s scope contemplates a collaborative arrangement, where it will work with Salt Lake Potash’s project team and manage the delivery of third-party process design and key equipment supply,” the company said. The construction scope will be performed on a target cost estimate basis, incentivising GR Engineering to achieve favourable budget and schedule outcomes, it added.

The engineering, procurement and construction contract involves the provision of plant, labour, materials and construction services for the process plant and non-process infrastructure, valued at A$85 million, while the engineering, procurement and construction management (EPCM) agreement contract involves the provision of services for the EPCM for areas of the process plant and non-process infrastructure,valued at A$22 million, Salt Lake Potash said.

Geoff Jones, Managing Director of GR Engineering, said: “We are extremely pleased to have been engaged to play a key role in the delivery of the process plant and non-process infrastructure for the Lake Way project. We look forward to continuing to work collaboratively with Salt Lake Potash to deliver safe and successful outcomes.

“GR Engineering looks forward to Salt Lake Potash emerging as a significant new Australian SOP producer.”

Last month, Salt Lake Potash contracted Veolia Water Technologies to supply HPD® crystallisation systems for Lake Way to help it produce a high-quality SOP fertiliser.

GR Engineering to grow Americas footprint with Hanlon Engineering buy

GR Engineering Services has entered into an agreement to acquire Hanlon Engineering & Associates Inc as it looks to grow its existing footprint within the Americas.

Hanlon, based in Arizona, USA, is a multi-disciplinary engineering services firm that provides engineering, procurement and construction management services to the mining sector in North America. It was established in 1999 and employs around 40 people. Hanlon also has a satellite office in Elko, Nevada.

Among the list of mining companies Hanlon has carried out work for is Agnico Eagle Mines, Barrick Gold, BHP, Freeport McMoRan Hecla Mining and Newmont.

GR Engineering’s Managing Director, Geoff Jones, said the acquisition of Hanlon was aligned with GR Engineering’s growth strategy.

“We are pleased to be acquiring the Hanlon business,” Jones said. “Hanlon has a strong local brand with an excellent safety record and longstanding relationships with major mining clients. Hanlon has an experienced management team capable of taking advantage of the numerous growth opportunities that exist in the Americas.”

Based on Hanlon’s current workflow, identified growth prospects and GR Engineering’s existing pipeline of work in the Americas, GR Engineering anticipates the business will immediately contribute to GR Engineering’s revenue and become earnings per share accretive for the company in the financial year ending 30 June 2021.

The acquisition remains subject to the satisfaction of several conditions precedent customary for an agreement of this nature. It is anticipated that the acquisition will be completed by the end of February.

GR Engineering to take on Woodlark gold process plant in PNG

GR Engineering Services looks like being rewarded for all of its hard work in Papua New Guinea (PNG) with the engineering, procurement and construction (EPC) contract for Geopacific Resources’ Woodlark gold project.

The ASX-listed mine developer says it has issued GR Engineering with an EPC letter of intent for the 2.4 Mt/y carbon in leach (CIL) process plant (modelled above), tailings line and other supporting infrastructure at the PNG project.

The final EPC contract is expected to be in the form of a guaranteed maximum price and will be signed following agreement of the final terms and conditions, Geopacific said.

“The company has selected an EPC contracting structure to de-risk the largest component of the capital expenditure requirement. Other remaining establishment capital costs also include site-based infrastructure and a mining fleet,” the company added.

In the meantime, Geopacific says it may instruct GR Engineering to commence an early works program to procure tenders and pre-order long lead time items such as the SAG and ball mills.

The processing plant will be constructed between the Kulumadau and Busai pits which are around 4 km apart. The project currently has 1 Moz in gold reserves, with significant upside from the 600 km² exploration licence, Geopacific said. The grade for the first five years is over 1.5 g/t Au with all-in sustaining costs estimated at A$866/oz ($586/oz).

GR Engineering is currently finishing off work on a crusher replacement project for Ok Tedi Mining in PNG.

Geopacific Managing Director, Ron Heeks, said: “GR Engineering has a strong reputation in successfully designing and constructing processing plants on time for a guaranteed maximum price. Geopacific is confident that their recent experience in PNG and strong track record in constructing similar projects will greatly de-risk the construction of Woodlark. We look forward to finalising the EPC contract, and advancing the development of Woodlark.”

GR Engineering Managing Director, Geoff Jones, said: “Our clients are increasingly seeking certainty and a track record of performance and GR Engineering has been able to demonstrate this to Woodlark, including by reference to its successful project outcomes in the turnkey design and construction of mineral processing plants in the gold sector.”

GR Engineering back for Boss Resources Honeymoon uranium project DFS

Boss Resources says it has appointed GR Engineering Services Limited (GRES) as the engineering and lead study consultant for its Honeymoon uranium project definitive feasibility study (DFS).

GRES will quickly ramp up the DFS work programs, due to the significant package of advanced technical work Boss has completed since it obtained the Honeymoon uranium project in South Australia from Uranium One (Australia) in December 2015 and, specifically, since the completion of the prefeasibility study in 2017, Boss said.

Honeymoon is a former-operating mine fully permitted to produce 3.2 MIb/y of uranium for export (one of only four mines in Australia). Based on previous studies, it is expected to require $58 million to ramp up output to 2 Mlb/y, according to Boss. It comes with a 63.3 MIb U3O8 JORC resource.

Work completed to date at Honeymoon includes:

  • A scoping study in 2016 for the recommissioning and expansion of the Honeymoon project;
  • Prefeasibility Study in 2017 that further refined the proposed strategy;
  • Field leach trial (FLT) that demonstrated Boss Resources’ improved leaching approach and validated its proposed ion exchange (IX) process;
  • Test work that optimised the process through improved resin elution and precipitation optionality
  • Trade-off studies that identified the preferred IX equipment (NIMCIX selected) and further optimised the flowsheet by simplifying the process steps;
  • An assessment of the drying and packing facility to provide upgrade options available to Boss to meet the planned production profile, and;
  • A preliminary assessment of the work required for the existing plant and infrastructure to meet operation requirements of Stage 1 production.

The DFS is due for completion in November 2019, according to Boss.

Boss Resources Managing Director, Duncan Craib, said: “GRES is a leading engineering and consultancy firm that has delivered multiple mining projects of significant size and scale, both domestically and overseas.”

The appointment continues Boss’ relationship with GRES, which completed the Honeymoon scoping study in September 2016 and the prefeasibility study in May 2017.

The scope for the DFS is based on two stages. Stage 1 includes re-commissioning of the existing SX facility and infrastructure including the various modifications required to improve performance, rectify problems identified during previous operations and make preparation for Stage 2 expansion.

Stage 2 includes supplementing the existing SX facility using a parallel IX process along with the expanded yellowcake drying and packaging capacity and modified raffinate/ground water treatment plant all to produce 2 Mlb/y of U3O8 equivalent.

The company said: “Boss will produce a combined DFS for the Stage 1 – Recommissioning, and Stage 2 – IX upgrade to achieve 2Mlb per annum U308. The DFS will improve on the work done in the prefeasibility study and deliver a Class 3 cost estimate with appropriate detail to achieve an accuracy of ±15%.”

The DFS will report on the design of the leach patterns for the wellfields and associated production scheduling based on these patterns and summarise the test work carried out to date, Boss added. It will also provide updated mineral resource and report on progress made against the updated permits.

The preliminary schedule for the DFS indicates wellfield design will be completed by the end of July, with ion exchange and uranium precipitation piloting due to be finalised by the end of August. Stage 1 reporting is due to be completed at the end of September, followed by Stage 2 at the end of October and the final report by mid-November.

BCI Minerals brings in GR Engineering for Mardie potash DFS

BCI Minerals says it has appointed GR Engineering Services as the lead engineer for the Mardie salt and potash project definitive feasibility study (DFS) on the northwest coast of Western Australia.

As lead DFS engineer, GR Engineering will be responsible for coordination and integration of the process and engineering design packages for the ponds and crystallisers, salt plant, sulphate of potash (SOP) plant and port facilities. It will also prepare and verify the DFS level capital and operating cost estimates and will undertake the design and supervision of pre-final investment decision site works and supporting infrastructure during 2019.

BCI said: “GR Engineering is a reputable Perth-based engineering group with significant experience in study management, engineering design and construction of resource projects in Western Australia and globally, both as engineering, procurement, construction and management and EPC contractor.

“Members of the GR Engineering team nominated for this engagement have appropriate experience in salt operation and sulphate of potash study management.”

Following completion of a prefeasibility study during the June 2018 quarter, BCI commenced the Mardie DFS. As well as improving design accuracy and further de-risking the project, BCI is aiming for the DFS to improve on the PFS development plan and business case in a number of key areas, including:

  • Increasing the production capacity to 4 Mt/y salt and 100,000 t/y SOP;
  • Establishing the tenure, approvals and designs for a fit-for-purpose export facility at the Mardie site, which will eliminate haulage costs to the Cape Preston East Port site, and;
  • Establishing test ponds and completing construction of project support infrastructure to bring forward the target date for first salt and SOP production.

The site works GR Engineering will initially carry out include a 135-ha trial pond, seawater intake pumps, circa-20 km upgrade of access roads, initial accommodation camp and power generation.

BCI’s Managing Director, Alwyn Vorster, said: “We are focused on delivering a high quality DFS that will place BCI in a strong position to reach a final investment decision by the first (March) quarter of 2020. GR Engineering’s technical ability and project management strengths will make them a valuable partner to BCI as Mardie is progressed towards full project construction.”

BCI’s areas of focus in the period to June 30, 2019, include:

  • Appointments of process design engineers (ponds, two plants and port);
  • Geotechnical drilling programme of pond, plant and port areas completed;
  • Construction of small-scale trial evaporators completed;
  • Port tenure negotiations with the Pilbara Port Authority(PPA);
  • Environmental Review Document submitted to the Environmental Protection Authority(EPA);
  • Construction of the 135-ha trial pond and supporting facilities (camp, roads, power, pumps) commenced;
  • Funding discussions with Northern Australia Infrastructure Facility and other entities progressed;
  • Product offtake potential developed, and;
  • Significant potential investor/financier briefings.

BCI said all activities until the final investment decision in Q1 2020 – estimated at A$25 million ($17.8 million) – will be funded from BCI’s existing A$36 million cash and the ongoing quarterly royalties from Iron Valley, the company said.