Case Studies

Kinross (Evander)

Kinross’ Evander tailings retreatment project provides a clear example of the risks associated with Direct CIP on historical tailings. Despite initial optimism, the project struggled with:

• Preg-robbing carbon
• Low leach kinetics
• High cyanide consumption
• Poor adsorption efficiency
• High detoxification costs

Ultimately, the project underperformed financially, demonstrating that CIP is not always suitable for complex tailings, even at moderate grades.

DRDGOLD (Ergo)

DRDGOLD’s Ergo operation is the global benchmark for large-scale tailings retreatment. Operating at grades as low as 0.25 g/t, Ergo demonstrates the power of:

• High-throughput systems
• Optimized flotation
• Efficient CIL circuits
• Low-cost deposition
• Strong environmental compliance

The key insight for investors is that Ergo’s success is built on flowsheet discipline and metallurgical optimization — not on grade alone.

For a 3.0 g/t resource, a flotation-based flowsheet would likely outperform CIP by an even wider margin.