Name of the Project
Rosemont openpit gold mine expansion.

Location
Western Australia.

Client
Regis Resources.

Project Description
The Rosemont project is a fully operational openpit gold mine, with a standalone crushing and grinding plant, piping an ore slurry to the Garden Well carbon-in-leach (CIL) processing facility. The current openpit mine is expected to continue until at least 2024.

The proposed project entails the development of an underground mining operation directly below the existing portal to be developed at the southern end of the Rosemont Main openpit.

The combined openpit and underground mine is expected to deliver 10.3-million tonnes of ore at 1.72 g/t of gold over a current five-year mine life. Openpit, Joint Ore Reserves Committee-compliant reserves of 356 000 oz comprise 62% of this schedule, with 214 000 oz expected to be delivered from the underground operation (38%).

The underground component of the expanded operation will exploit the underground mineral resource estimate at Rosemont of 1.4-million tonnes at 5.1 g/t gold for 230 000 oz of gold at a 2.g/t gold cutoff grade. The fully diluted underground mining schedule is designed to deliver stoping ore of 666 000 t at 4.8g/t at Rosemont Main and 1.15-million tonnes at 3 g/t at Rosemont South.

Mining will be conducted using long-hole open stoping, in a top down sequencing, with no backfill in Rosemont South leaving pillars for local and regional support and a combination of cemented rock fill and waste rock fill backfill in Rosemont Main.

The underground mine plan will be developed from an initial access portal in the southern end of Rosemont Main pit and then two subsequent ventilation portals in the Main and South pits

The existing Rosemont crushing and grinding plant and the Garden Well CIL processing facility will be used to treat the material mined from the underground operation at an estimated recovery factor of 97%.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
Not stated.

Value
Preproduction capital is estimated at A$29.4-million. A further $9.7-million is forecast over the life-of-mine.

Duration
Portal development in the southern end of Rosemont Main is expected to start in the March 2019 quarter, with processing of the underground material expected to start in the December 2019 quarter.

Latest Developments
Regis Resources has approved a A$29.4-million investment to develop the underground operation at Rosemont.

Meanwhile, an updated mineral resource estimate, which will include recent infill and extensional drilling, is expected to be completed in the current quarter.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Too early to state.

Contact Details for Project Information
Regis Resources, tel +61 8 9442 2200, fax +61 8 9442 2290 or email enquiries@regisresources.com.