TSX-V-listed gold explorer and developer Osino Resources is progressing with developing a definitive feasibility study (DFS) for its Twin Hills gold project, in Namibia, and is conducting trade-off studies and assessing risks and opportunities for infrastructure enhancement, and water and power supply in particular.
An existing preliminary feasibility study for the project was based on proven and probable gold reserves of 2.15-million ounces at a grade of 1.04 g/t.
DFS work on the project started in October 2022, with various main consultants appointed, including Lycopodium to conduct the overall compilation of the technical report and DRA to undertake infrastructure design, cost estimation and coordination of specialised consultants.
The DFS, which Osino plans to release mid-year, is based on a conventional crushing, milling, gravity, pre-oxidation and carbon-in-leach (CIL) circuit.
Osino co-founder, president and CEO Heye Daun says the company has employed two engineering, procurement and construction management contractors, Lycopodium and DRA/Senet, both of which have an extensive and successful record of delivering gold projects in Africa.
“Their experience has proven to be highly beneficial in ensuring that risks identified in earlier stages of project development are being mitigated during the DFS.
“The DFS will further de-risk the project and showcase its potential as one of the top-tier, near-term, undeveloped gold projects in Africa,” he says.
In parallel to the technical work that is under way, Daun says Osino is advancing financing discussions with potential financiers as it gets closer to making a formal construction decision.
To date, Osino has selected several options to progress with the project, including a standard primary crusher, coarse ore stockpile, secondary and tertiary crushing, covered fine ore stockpile and ball mill circuit in preference to other alternatives.
Going forward, the developer is preparing mass balance, process design criteria, block flow and process flow diagrams, including mechanical equipment lists.
Data sheets, specifications and requests for quotation to vendors have been issued with capital and operating cost estimates expected to be compiled this month and in March.
The Twin Hills project – located in the Damara sedimentary mineral belt in close proximity to and along strike of the producing, openpit Navachab and Otjikoto gold mines – is amenable to conventional openpit gold mining and conventional, whole-ore CIL metallurgical processing.
CIL tailings will be de-toxified, filtered and transferred to a lined tailings storage facility (TSF).
Meanwhile, Qubeka Mining Consultants has been appointed to conduct enhancement, design, scheduling and cost estimates for the openpit mining operation, while Knight Piésold has been commissioned to design and cost estimate the filtered TSF and extend the hydrogeological model of the project.
Subordinate consultants include CSA Global for resource estimation; SRK for geotechnical and geophysical works; ECC for environmental work; SLR to undertake hydrocensus updates; FL Smidth, Paterson & Cooke, Bokela and STL for tailings filtration test work; GSFA for bulk power supply; Kuchling & Associates for bulk water supply; Dornier Suntrace for renewable power supply; and Collis & Associates to conduct sustainability work.
The capital and operating cost estimates will be updated during the next two months and are based on quotations, as opposed to mostly factoring in the preliminary feasibility study.
Osino notes that various capital cost saving opportunities have been identified and will be reflected in the DFS estimate.