This report describes the processing facilities, metallurgical testwork, and historical plant performance for the South Deep Gold Mine as of 31 December 2021.
Report context
This Technical Report, prepared in accordance with National Instrument 43-101, addresses the South Deep Gold Mine in South Africa with an effective date of 31 December 2021. The report was prepared by Gold Fields Limited. The processing-related information is drawn from Sections 13 (Mineral processing and metallurgical testing), 16 (Mining methods), and 17 (Recovery method) of the report.
Processing route
Run-of-mine treatment flow sheet and design
The proposed flow sheet for run-of-mine treatment is described in Section 17.1.1. The design incorporates a crushing circuit, a milling circuit, flotation, classification, ultra-fine grinding, and cyanide leach with carbon-in-pulp recovery.
Tailing retreat
Section 17.1.2 describes a proposed tailing retreat component of the processing route.
Recent process plant performance
Section 17.2 reports historical operating data on recent process plant performance. Section 13.2.3 provides further detail on process plant metallurgical performance from testwork and operating results.
Metallurgical testing , North of Wrench (NoW)
Section 13.2.1 reports that metallurgical testwork has been conducted on samples from the North of Wrench (NoW) area. Testing procedures and relevant results are described, although specific flowsheet details for NoW material are not provided in the report sections presented.
Metallurgical testing , South of Wrench (SoW)
Section 13.2.2 describes metallurgical testwork conducted on samples from the South of Wrench (SoW) area. Testing procedures and relevant results are reported.
Plant sampling and reconciliation
Section 13.3 addresses plant sampling and reconciliation procedures at the processing facility.
Deleterious elements
Section 13.4 reports on deleterious elements identified in the process feed. Section 13.5.2 further discusses deleterious elements as a metallurgical risk.
Metallurgical risks
Section 13.5 identifies metallurgical risks including sample representativity (Section 13.5.1) and deleterious elements (Section 13.5.2). Additional processing risks are listed in Section 17.4, including major equipment failure (Section 17.4.1), plant operational management (Section 17.4.2), and operating costs, plant consumables and reagents (Section 17.4.3).
Process plant requirements
Section 17.3 addresses process plant requirements for ongoing operations.
Key reported parameters
| Parameter | Value | Basis |
|---|---|---|
| Processing route | Crushing, milling, flotation, classification, ultra-fine grinding, cyanide leach, carbon-in-pulp | Proposed design |
| Tailings retreat | Comminution and leaching of tailings material | Proposed design |
| Plant sampling and reconciliation | Conducted at process facility | Historical operating data |
| Deleterious elements identified | Reported in process feed | Testwork/historical data |
| Metallurgical risks identified | Sample representativity; Deleterious elements; Major equipment failure; Plant operational management; Operating costs and consumables | Reported assessment |
| North of Wrench testwork | Conducted | Testwork |
| South of Wrench testwork | Conducted | Testwork |
| Process plant metallurgical performance | Reported | Historical operating data/testwork |
| Process plant requirements | Addressed | Design/operating basis |
Project website: https://www.goldfields-southdeep.co.za/
Technical qualifications
The processing information presented in this report is subject to specific limitations. Metallurgical risks concerning sample representativity are noted in Section 13.5.1. Deleterious elements in the ore feed present a processing risk, as identified in Sections 13.4 and 13.5.2. Operational risks include major equipment failure (Section 17.4.1), plant operational management challenges (Section 17.4.2), and sensitivity to operating costs, plant consumables, and reagents (Section 17.4.3). No detailed flowsheet dimensions, throughput rates, or specific reagent consumptions are provided in the report sections extracted.
Source: *Technical Report – National Instrument 43-101, South Deep Gold Mine, South Africa*, effective date 31 December 2021, Sections 13, 16, and 17. Prepared by Gold Fields Limited.
