Tag Archives: Sanbrado

West African Resources spells out Kiaka gold mine potential

West African Resources has released the results of a feasibility study for its 90%-owned Kiaka gold project in Burkina Faso, heralding a potential open-pit mining operation that can support a processing plant throughput of 8.4 Mt/y.

Kiaka is 140 km southeast of Ouagadougou, and 45 km south of the company’s existing Sanbrado gold mine.

The Kiaka mining study is based on conventional open-pit mining methods, with run of mine ore being directly fed to the crushing circuit. Mining operations will use a combination of 140 t (Cat 6015) and 230 t (Cat 6020) hydraulic excavators matched to 95 t dump trucks (Cat 777s).

Drill and blast will be required from near surface, with the parameters selected based on the relatively hard rock mass qualities and the required selectivity for mining of the ore. Given the broad mineralised zone, a portion of the blasting will be able to be undertaken on 10-m benches with more selective zones blasted on 5-m benches, the company noted. As such a combination of top hammer (Sandvik Panterra DP1500) and downhole hammer (Sandvik Leopard DI650) capable blast hole rigs will be employed.

To achieve the targeted processing rate, a total material movement averaging 21 Mt/y is required for the first seven years of the production schedule. With the pit staging deferring waste movement, this increases to an average of 35 Mt/y for the next six years of production before reducing to an average of 15 Mt/y for the remainder of the mine life.

The production profile is suited to an initial fleet of 2 x 230 t excavators and 1 x 140 t excavator matched to 95-t class trucks. The fleet will increase to 3 x 230-t excavators with 2 x 140-t excavators for the higher production requirement. Further work to investigate bulk mining scenarios and optimise fleet selection will be conducted, with further refinement of the drill and blast parameters also being undertaken in conjunction with fleet optimisation.

Kiaka’s free-milling gold ore is intended to be processed through a conventional single stage gyratory crushing and semi-autogenous ball mill crusher (SABC) milling circuit followed by carbon-in-leach (CIL) processing. Extensive metallurgical test work indicates Kiaka will deliver life of mine gold recoveries of 90% at a nominal 100-micron grind size.

Following review of the option studies the company selected the following major equipment:

  • Primary gyratory crusher – a Metso Outotec Superior™ MKIII 54-75;
  • SAG mill – 18 MW; and
  • Ball mill – 9 MW

The crusher can achieve 8.4 Mt/y for the design blend at 65% availability. At a 70% loading, the throughput rate ranges from 9.2 Mt/y to 10.2 Mt/y on the design blend. The selected mills also have higher than typical design margin for the nameplate throughput rate with modelling conducted by OMC showing the selected comminution circuit is capable of a throughput of:

  • 8.4 Mt/y (1,050 t/h) for 100% fresh ore feed when the 80th percentile ore characteristics are used;
  • 9 Mt/y (1,125 t/h) for 100% fresh ore when modelled at the average (50th percentile) ore characteristics;
  • 14 Mt/y (1,750 t/h) for 100% oxide ore feed; and
  • 10 Mt/y (1,250 t/h) for a blended feed of 23% oxide and 77% fresh ore.

On a 100% basis, life of mine (18.5 years) production is scheduled to come in at 219,000 oz/y of gold.

West African Executive Chairman and CEO, Richard Hyde, said: “Kiaka will access power from the Burkina Faso grid predominantly supplied by low-carbon hydroelectric power from Ghana and the Ivory Coast with large Burkina Faso low-carbon solar projects planned to come online early in the mine life to supplement the grid.”

Hyde says WAF will investigate expanding Kiaka to plus-10 Mt/y through the addition of secondary crushing and debottlenecking the process circuit, as well as evaluating tenders for key major equipment received during the feasibility study, which had ranged widely in price and delivery lead times.

“There remains scope to reduce the capital expenditure and cost contingencies on this equipment, as well as shorten the lead times,” Hyde said. West African Resources is also looking at an owner-mining versus contractor (the current plan) study looking to lower mining costs and VAT working capital.

Second Gekko InLine Leach Reactor heads to West African Resources’ Sanbrado mine

Gekko says a second InLine Leach Reactor (ILR) has been ordered by West African Resources for its 90%-owned Sanbrado gold mine in Burkina Faso.

The order is one of several to have emerged on the back of strong gold prices, with interest from a range of milling operations across the globe including Russia, North America, South America and Africa, Gekko says.

First developed in 1997, the ILR has provided an alternative from traditional physical separation steps, such as using recovery tables, into a lucrative chemical separation process.

It offers superior recoveries in a proven, high efficiency, safe and highly secure system, according to the company.

Available as a completely automated batch model for processing high grade gravity gold concentrates, the ILR can also be configured as a continuous model for treating high throughput gold, silver and complex sulphide concentrates from InLine Pressure Jigs and flotation circuits.

“The ILR’s innovative design and unparalleled flexibility in gold and silver leaching chemistry is providing cost and production benefits to operations across more than 40 countries across the globe,” Gekko said.

Construction on Sanbrado commenced in late 2018, with first gold poured in March 2020, six months ahead schedule and $20 million under budget.

West African anticipates Sanbrado will produce between 250,000-280,000 oz of gold at all-in sustaining costs of $720-800/oz.

The company says: “The estimated operating costs for the project highlight that the project will be a conventional, low cost and high margin operation. This is a result of high grade ore from M1 South and the significant proportion of oxide and transition material in the mine schedule and the free milling nature of all ore types (average life of mine recovery of 93%), low reagent consumption and a high component of gravity recoverable gold.”

West African moves into new phase at Sanbrado following gold pour

West African Resources says it has poured first gold at its Sanbrado gold project, in Burkina Faso, just over a week since confirming construction activities had been completed on all areas of the process plant and tailings storage facility.

The inaugural pour occurred on March 18, with gold bars weighing 23.9 kg (768 troy ounces) poured in the first smelt on site.

Since processing started up, 75,000 t of ore at 1.5 g/t Au has been processed, with indicative metallurgical recoveries of over 90%, West African said.

The process plant has also exceeded nameplate capacity for the past seven days of production, the company noted.

Open-pit ore stockpiles are also building with 250,000 t at 1.5 g/t Au on the run of mine pad, the company noted, adding that first underground development ore had been mined and stockpiled, ready to process.

West African Executive Chairman, Richard Hyde, said: “This is a major milestone for West African Resources and marks the beginning of a new phase in the WAF story. To successfully transition from an exploration company to a gold producer is without doubt a great achievement for all involved.

“I would like to thank WAF’s owners’ team and all consultants, contractors and other stakeholders for their hard work and support over the last four years to bring Sanbrado from discovery into production.”

West African a month away from first gold pour at Sanbrado

West African Resources says it has processed the first ore at its Sanbrado gold project in Burkina Faso, putting it on course to produce its inaugural gold product within the next month.

Construction activities have now been completed on all areas of the process plant and tailings storage facility, according to the company.

All four heavy fuel oil generators have been commissioned in the power station and are now operational, while the desorption and gold room circuits are undergoing commissioning in preparation for a maiden gold pour within the next four weeks.

Open-pit mining contractor, African Mining Services, a subsidiary of the Perenti Group, has ramped up mining activities to include both the M5 and M1 South pits, with day and night shifts starting in the past week, West African said.

Currently, over 360,000 t of oxide ore is stockpiled on the run of mine pad at an average grade of 1.5 g/t Au.

Underground development continues to progress on-schedule with mining contractor Byrnecut Offshore, a subsidiary of the Byrnecut Group, having completed the primary ventilation raisebore. The ventilation fan is also currently being installed. First development ore remains on track for late March and first stoping ore is forecast for the September quarter, the company said.

West African Executive Chairman, Richard Hyde, said: “This is a major milestone for West African Resources and testament to the quality of our team and contractors. Commissioning activities will continue over the next four weeks with the first gold pour on track for early Q2 (June quarter) 2020.”

An updated feasibility study on Sanbrado from 2019 envisaged an initial 10-year mine life, including 6.5 years of underground mining, with probable reserves of 1.7 Moz (21.6 Mt at 2.4 g/t gold). The project was expected to have average annual production over the first five years of 217,000 oz gold with all-in sustaining costs of less than $600/oz.

West African picks Ausdrill’s AUMS for Sanbrado open-pit mining

Ausdrill, through its wholly-owned subsidiary, African Mining Services (AMS), has been selected by West African Resources as the preferred open-pit mining contractor for the Sanbrado gold project, in Burkina Faso.

Sanbrado, a low-cost, high-grade operation only 90 km from the country’s capital, Ouagadougou, will be the 14th commercial gold mine in Burkina Faso in 14 years. It is forecast to have average annual production of 217,000 oz/y of gold at all-in sustaining costs of less than $600/oz in its first five years of mine life.

The AMS scope of work includes a full suite of open pit mining services – including site preparation, drill and blast, load and haul, and maintenance works – over a five-year term, generating approximately A$235 million ($160 million) in revenue under a schedule of rates contract, Ausdrill said.

AMS anticipates it will employ some 190 personnel at the project, with the workforce to be predominantly local, and use a mix of new and existing equipment to deliver on the project.

AMS and West African Resources are in the process of finalising the contract terms, which will include the provision of an optional deferred payment arrangement for up to $10 million at a commercial interest rate, with works expected to commence in early 2020. West African Resources said mobilisation activities were expected to commence in November, ahead of open-pit mining commencement in January 2020.

Ausdrill Group Managing Director, Mark Norwell, said: “A key focus for the new Ausdrill group has been to enhance our surface operations in Africa and target substantial growth opportunities across a range of commodities in select African countries.

“Being selected as preferred contractor at the Sanbrado gold project is a significant achievement and represents the excellent progress we are making in building on the suite of quality projects on which AMS operates in the region.”

West African Resources Managing Director, Richard Hyde, said: “Sanbrado is the highest margin gold project in construction in West Africa and we are on target for approximately 300,000 oz of gold in the first 12 months of production. We look forward to partnering with AMS to bring this fully funded project into production in mid-2020.”

Byrnecut wins underground mining contract at WAF’s Sanbrado gold project

West African Resources has awarded the underground mining contract for the M1 South deposit at the Sanbrado gold project in Burkina Faso to Byrnecut.

The contract, worth $110 million over five years, is Byrnecut’s second in the West African country.

Mobilisation activities are expected to commence in December with portal establishment planned for March.

Works under the contract include underground portal establishment for M1 South, decline and level development of 7 km, ore driving of 2 km and 200,000 t, stope production of 1.3 Mt, and raise drilling and cemented rock backfill.

West African Managing Director Richard Hyde said: “The underground mining contract is a key operational contract for Sanbrado and its award follows the completion of a competitive tender process and extensive due diligence process examining safety, experience and capabilities.

“We are very pleased to award the underground mining contract to Byrnecut who have a long history providing underground mining services globally and have current operating experience in West Africa.”

Byrnecut Group Executive Chairman Steve Coughlan said: “We are looking forward to partnering with West African on the exciting Sanbrado gold project. This project will be our second site in Burkina Faso and fifth project we have operated in the West African region.”

The M1 South underground will kick-off WAF’s mining development at Sanbrado, with the underground development accessing high-grade, free-milling gold mineralisation located directly beneath the proposed M1 South open pit at approximately 120m vertical.

Concurrent mining of the M1 South open pit ore from surface and underground will accelerate cash-flow over the early years of the Sanbrado mine life, the company says.