The Phoenix operation, located adjacent to Harmony’s current and historical operations in the Free State, involves the retreatment of tailings from tailings storage facilities in the region to extract any residual gold. Material contained in the TSFs originates from deep level gold mines, operated by Harmony and other mining companies. The mining operations predominantly extract narrow, tabular gold-bearing conglomerate reefs, namely the Basal, B, Elsburg (EA), Dreyerskruil and Beatrix Reefs. These reefs occur within the Archean Witwatersrand Basin which hosts the Witwatersrand Supergroup succession. The Basal Reef is located at the base of the Harmony Formation, within the Johannesburg Subgroup of the Central Rand Group (“CRG”). The B Reef is part of the Spec Bona Member at the base of the Aandenk Formation, within the Turffontein Subgroup of the CRG. The Beatrix Reef is part of the Earls Court Member of the Aandenk Formation, within the Turffontein Subgroup of the CRG. The Elsburg (EA) and Dreyerskruil Reefs occur within the Eldorado Formation of the Turffontein Subgroup, capping the CRG in the Free State Goldfield. The TSF material is the waste product of crushing, milling and gold extraction by carbon-in-leach (“CIL”) or CIP methods. As man-made deposits the TSFs are not the result of natural sedimentary processes. The grade of the TSFs is a function by the grade of the original reef sources, and the efficiency of the processing method at the time of treatment.

Hydro-mining on two TSFs, Brand A and Dam 21, for the Phoenix operation and one TSF, FSS5 for the Central Plant retreatment project, is conducted under contract. Material is reclaimed using high-pressure water on the TSF, from where the material is pumped to the Saaiplaas plant in separate rubber-lined pipelines from Brand A and Dam 21, and to Central Plant from FSS5.

Two surface sources are currently being mined:
• The Brand A TSF has had some 65% of its material removed already. It has a grade of 0.28g/t Au at 40% to 45% recovery;
• The 21 TSF (which replaced the Harmony One TSF as a source from end-2011) has a grade of 0.27g/t Au at 40% to 45% recovery;
• All the material from the Harmony One TSF has been reprocessed with only the clean-up remaining.

The hydro-mining (monitoring) process uses 100mm and 150mm diameter high-pressure water monitors (cannons) to re-pulp the consolidated slimes to a relative density of around 1.4. The re-pulped slime flows under gravity to an in-dam finger screen where large trash is removed and then to the sump from where a transfer pump delivers it to one of two vibrating screens for secondary screening to remove oversize and smaller trash material. The screen underflow falls into the transfer sump. A separate pump station at each reclamation TSF pumps the reclaimed screened pulp via rubber lined pipelines to the plant.

The transfer pumping of slimes to Saaiplaas and Central plants is done by E ........

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