Name of the Project
Sihayo starter project.

Location
Mandailing Natal, North Sumatra, Indonesia.

Project Owner/s
Sihayo Gold.

Project Description
Sihayo has completed an updated feasibility study to improve the technical definition of the Sihayo starter project and derisk its implementation through a series of work streams.

The updated feasibility study has shown proven and probable reserves of 11.5-million tonnes grading 2 g/t gold. The mining method adopted for the 2022 updated feasibility study is conventional openpit mining using diesel hydraulic excavators and diesel articulated dump trucks.

In the revised mine plan, the throughput rate has increased from an average of 1.6-million tonnes a year in the 2020 definitive feasibility study (DFS) to 1.9-million tonnes a year in the 2022 updated feasibility study, owing to an increase in mill size.

The Sihayo process plant has been designed to treat the expected range of ore types to be delivered during the life-of-mine (LoM) mining schedule and has resulted in the mine life decreasing from 8.5 years to 6.5 years. The 2022 updated feasibility study process design now incorporates a 5.7 MW semiautogenous grinding (SAG) mill. A 3.8 MW SAG mill was initially adopted for the 2020 DFS design.

Another significant change to the processing plant design is the inclusion of an additional crushing station to more effectively manage the oxide ore.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The project has an after-tax net present value, at a 5% discount rate, of $50-million and an internal rate of return of 10.1%, with a payback of
4.75 years, in the 2022 updated feasibility study. This compares with an after-tax net present value, at a 5% discount rate, of $205-million and an internal rate of return of 28% in the 2020 DFS.

Capital Expenditure
Upfront capital costs have increased from $154-million in the 2020 DFS to $243-million.

Planned Start/End Date
Mine development allows for a 12-month preproduction period comprising six months of access development, six months of combined development and prestrip mining.

Latest Developments
None stated.

Key Contracts, Suppliers and Consultants
AMC Mining Consultants (mine optimisations, mine design and scheduling, operating and capital cost estimates for mining activities and equipment); Primero Engineering (updated process plant design, estimation of processing consumables to derive operating cost estimates); Merdeka Mining Services (earthworks, roadworks, civil works, building design and associated cost estimates); Knight Piésold (tailings storage facility design to a level required for submission to Indonesian Dam Safety Committee); Ground Risk Management (geotechnical investigations); and Lorax (environmental and community requirements).

Contact Details for Project Information
Sihayo Gold, tel +61 3 9935 9161 or email sihayogold@sihayogold.com.