Sunrise Dam

Overview

AngloGold Ashanti’s sole operating mine in Australasia is Sunrise Dam.

The Sunrise Dam gold mine is located in the northern goldfields of Western Australia, 220km northeast of Kalgoorlie and 55km south of Laverton.

Production from Australasia declined by 1% to 396,000oz in 2010, equivalent to 8.8% of group production. Total cash costs increased by 48% to $982/oz, whilst in local currency, total cash costs rose 29% to A$1,070/oz, due primarily to the increase in the unwinding of deferred stripping costs. In all, 494 people, including contractors were employed, 39 more than in 2009. Total attributable capital expenditure for the region, including Tropicana, was $40m, a decrease of 77% on the $177m spent in 2009, which included the Boddington project that was sold. The bulk of this was spent on Ore Reserve development at Sunrise Dam and at Tropicana.

Location

The Sunrise Dam gold mine is located in the northern goldfields of Western Australia, 220km northeast of Kalgoorlie and 55km south of Laverton.

The mine consists of a large open pit which is now in its fourteenth year of operation, and an underground mine which began in 2004. Mining is conducted by contractors and the ore is treated in a conventional gravity and CIL processing plant, which is owner-managed. 

Geology and Mineralization

Located in the Laverton Tectonic Zone, the Archaean Cleo-Sunrise deposit is divided by a N-S tenement boundary. Gold is located in three broad settings: gently-dipping shear zones which are characterised by intense hydrothermal alteration and strongly deformed quartz veins; steeply-dipping shear zones, which are characterized by vein stockworks and gold-rich breccias; and within Tertiary transported rocks, particularly at the base of palaeochannels. All rock types at Cleo-Sunrise are mineralised, but gold is best developed where significant structures intersect Fe-rich sedimentary rocks (BIF).

Mining & Operation

Production in 2010 decreased by 1% to 396,000oz, from 401,000oz the previous year. This was equivalent to 9% of group gold production. The decline reflects the marginally lower average grade of ore processed as anticipated in the mine plan. Open-pit mining continued in the North Wall Cutback providing over 80% of production. Ore continued to be sourced from a combination of underground and open pit operations with the use of lower-grade stockpiles to supplement the ore feed to the plant.

Underground tonnage decreased by 12%, or 94,000t, to 686,000t. Underground ore yielded approximately 75,000oz, contributing 19% to total mine production compared with 28%, or 111,000oz, the previous year.

Total cash costs increased by 48% to $957/oz, from $646/oz in 2009. In local currency terms, costs rose by 29% to A$1,043/oz. The higher costs were in line with expectations and primarily due to the accounting effects of deferred stripping costs of A$285/oz. Deferred stripping costs for the open-pit will continue to impact upon cash costs until the end of 2013. The lower production base also placed upward pressure on unit costs.

Processing

The treatment plant uses conventional CIL technology and includes a gravity circuit to extract coarse gold. 

Environment & Community

A mine closure plan is in place and progressive rehabilitation in line with this plan is being undertaken. Governance reporting for Energy Efficiency Opportunity, National Greenhouse and Energy Reporting, and National Pollutant Inventory is being maintained and is in compliance with government regulations.