Name of the Project
Pedra Branca East (PBE) copper/gold project.

Location
The site is about 20 km directly south-west of Canaã dos Carajás, in Brazil.

Client
Avanco Resources.

Project Description
Pedra Branca comprises two adjacent high-grade, steeply dipping copper/gold deposits – PBE and Pedra Branca West (PBW).
PBE hosts a mineral resource of 10.48-million tonnes grading 2.8% copper and 0.7g/t gold. This resource remains unchanged since 2016.
The PBE prefeasibility study has demonstrated the viability of a large-scale standalone underground, sublevel open-stoping (SLOS) mining operation. It is planned that underground development will be undertaken by a contractor. Avanco will be responsible for SLOS.

SLOS (bench-and-fill) with delayed filling has been selected as the most appropriate mining method for PBE, as the mineralisation is relatively wide and competent, steeply dipping with strong wall rocks, with favourable operating and preproduction capital costs. This method minimises the waste development required and allows for the use of ‘nonentry’ mining techniques using radio remote-controlled loading from the open stope.

Backfill will be by means of cemented paste fill supplied through a series of boreholes and pipes connected to the backfill plant on surface.
A 1.2-million-tonne-a-year processing plant will be built, comprising three-stage crushing, single-stage ball milling, traditional copper rougher/cleaner/cleaner scavenger and recleaner flotation circuit, with early production of final concentrate on the first rougher cell.

Concentrates from the other rougher cells will be reground before entering the cleaner circuits. Copper concentrates will be dewatered to about 8% moisture using a high-rate thickener and filter press.

Tailings will be thickened and pumped to either the paste fill plant or to a conventional tailings management facility (TMF), with tails being beached along the upstream face of the impoundment wall. The TMF has been sized to cater for two consecutive high rainfall years. Water will be reclaimed for process use from the TMF using a floating pump pontoon.

The paste fill plant will further densify the tailings prior to mixing with cement and being pumped underground for stope filling.
Over the 11.5-year mine life, it is expected that about 5.7-million tonnes of paste will be required, with about 4.4-million tonnes of tailings being transferred to the TMF.

Jobs to Be Created
The project is expected to create about 447 jobs.

Net Present Value/Internal Rate of Return
The project has a net present value, at 7% discount rate, of $200-million and an internal rate of return of 34%.

Value
Project implementation costs have been estimated at $158-million.

Duration
Twenty-seven months.

Latest Developments
Avanco has started a definitive feasibility study on Pedra Branca, which is expected to be completed before the end of May 2018.
Infill and extensional drilling is planned for later this year.
A boxcut and portal have been established.
Trial mining on the top of the orebody (35 m) is under consideration to provide a bulk sample and geotechnical information.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Not stated.

Contact Details for Project Information
Avanco Resources head of corporate affairs Nicholas Bias, tel +61 497 888 227 or email nbias@avancoresources.com.