Name of the Project
Long Island strategy.

Location
The project is a brownfield initiative at the Tropicana mine, located 330 km east-north-east of Kalgoorlie, in Western Australia.

Client
Tropicana Joint Venture, which comprises AngloGold Ashanti Australia (70%) and Independence Group (30%).

Project Description
The Long Island strategy aims to increase gold production from the Tropicana mine in the medium term and extend the mine’s life.

The strategy provides optionality and flexibility, with eight mining stages and three decision points allowing for adjustment to changing economic conditions. If all three phases are implemented, mine life will be extended to 2027 and increase Tropicana’s mining rate to between 95-million tonnes and 107-million tonnes a year.

The strategy involves using a strip-mining approach that minimises waste haulage distances by using in-pit backfill rather than trucking the material over long distances to surface waste dumps.

Phase 1 of the strategy entails mining the Havana South pit and a cutback of the Boston Shaker pit, which uses the completed Tropicana pit as the first backfill location.

If all three phases of the Long Island strategy are implemented, 2.1-million ounces of gold will be added to Tropicana’s business plan, extending mine life by about seven years to 2027.

The project value has also been enhanced by the decision to install a 6 MW ball mill in the processing plant. 

The additional ball mill follows a range of expansion and optimisation projects that have lifted the throughput rate at commissioning from a nameplate capacity of 5.8-million tonnes a year to about 7.6-million tonnes a year by the end of 2017.

The ball mill will enable the throughput rate to be lifted to about 8.1-million tonnes a year and, through a reduction in grind size, baseline metallurgical recovery will be improved by up to 3% to about 92%.

The increased throughput will efficiently match processing capacity to the Long Island mining rate and bring forward delivery of the best gold production profile for the operation. The improved recovery rate will add an estimated 120 000 oz to recovered gold over the life-of-mine.

The Long Island strategy is underpinned by continued exploration success, with the ore reserve having increased to 66.59-million tonnes grading 1.91 g/t for 4.08-million ounces.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
Not stated.

Value
The capital expenditure related to Long Island will be about A$18-million, primarily for expansion to the accommodation camp and heavy-vehicle workshop infrastructure.

Total capital expenditure on the new ball mill is expected to be about A$28-million, including equipment, construction cost and spares.

Duration
The new ball mill is scheduled to be commissioned in the fourth quarter of this year.

Latest Developments
The Tropicana Joint Venture has approved Phase 1 of the strategy.

A prefeasibility study (PFS) will be undertaken this year to investigate the potential for underground mining at Boston Shaker to define an underground ore reserve by the end of the calendar year. The PFS will include infill drilling and mining studies.

Successful development of an underground mine at Boston Shaker has the potential to contribute high-grade ore to the processing plant from 2021 onwards.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Too early to state.

Contact Details for Project Information
AngloGold Ashanti Australia, Andrea Maxey, tel +61 8 9425 4603/+61 400 072 199 or email amaxey@anglogoldashanti.com.au.