Following the publication of a robust prefeasibility study (PFS) in January, West Africa-focused gold producer Thor Explorations expects to start construction at its Senegal-based Douta gold project this year with the aim of achieving first gold in 2028, alongside ongoing exploration.

Located within the Birimian rocks of the Kéniéba inlier in eastern Senegal, the Douta project comprises a northeast-trending mining lease application covering 58 km2, along with the Douta-West and Bousankhoba exploration permits.

To consolidate ownership, Thor signed a binding sale and purchase agreement with joint venture partner Birima Resources to acquire the remaining 30% of the Douta-West permit in January.

“This acquisition positions us to own the entire Douta project, consisting of the Douta and Douta-West licences, on a 100% equity basis and allows for an efficient development process and full exposure to the project economics prior to the government of Senegal’s 10% free carried interest,” says Thor Explorations president and CEO Segun Lawson.

The PFS is based on five openpit gold deposits feeding a central gold processing facility.

The deposits will be mined by conventional openpit operations and mining is scheduled to start at the end of 2027, with plant commissioning and ramp up during the first quarter of 2028.

However, this timeline is contingent on the finalisation of Thor’s mining convention with Senegal’s government, which the company expects to complete in the first half of this year.

The project’s environmental and social impact assessment (ESIA) was approved in January, serving as a key milestone.

“The results confirm Douta as a high quality gold project with strong economics, a short payback period and long-term leverage to the gold price through its significant indicated resource base,” he adds.

In addition to finalising the mining convention, Thor’s next steps include starting detailed design, finalising financing packages, ordering long-lead items and continued evaluation and refinement of the metallurgical recoveries of the oxide, transitional and refractory ores.

Douta as a Project
The Douta project envisages a 12.6-year life-of-mine (LoM), comprising of the Oxide Ore Phase – which focuses on the recovery of cyanide-soluble gold, and the Primary Ore Phase – which focuses on the recovery of gold hosted in sulphides and silicates.

The Oxide Ore Phase will produce about 413 000 oz in the first four years, during which the project will have an average yearly gold production of over 111 000 oz at an all- inclusive sustaining cost of $1 469/oz in the first three years, says Lawson.

The Oxide Ore Phase currently spans four years of mining and processing oxide and transitional ores through a conventional carbon-in-leach (CIL) circuit, which consists of crushing, milling and gravity recovery of free gold, followed by leaching of gravity tailings, elution and gold smelting, and tailings disposal.

Following the Oxide Ore Phase, the Primary Ore Phase continues operations for a further 7.8 years, during which fresh ore will be mined and processed through the same CIL circuit but enhanced by a suspension roaster. The suspension roasting process will expose refractory gold particles prior to cyanide leaching.

The Primary Ore Phase circuit will consist of a pre-roasting dewatering stage, pre- roasting product storage silo, suspension roasting, and calcine repulping and regrinding.

During this phase, the plant will treat 2.4-million tonnes a year of fresh, sulphide ore, producing an average of 61 000 oz/y.

At the end of the mine life, the final seven months will see the treatment of an additional 2.3-million tonnes of mixed oxide and transitional ore mined and stockpiled during mining of the sulphide ore – a phase intended to yield 47 000 oz of gold.

Thor intends to fund Douta’s construction from its existing balance sheet, supported by strong cash flows from its Segilola gold mine in Nigeria; at the end of 2025, the company held a cash balance of $137-million.