Strategic Risks

The Direct CIP Trap

Direct CIP appears simple and familiar, but for historical tailings it carries structural risks that can permanently impair project economics.

The most significant risk is **preg-robbing**, where natural carbon in the ore adsorbs dissolved gold before it reaches the activated carbon circuit. This can cap recoveries at 40–55% even with aggressive cyanide dosing.

Additional risks include:

• High cyanide consumption
• High lime consumption
• High power draw for agitation
• Large detoxification circuits
• High environmental bonding requirements
• Large cyanide-bearing TSF liabilities

These risks compound to create a scenario where CIP becomes economically uncompetitive against flotation-based flowsheets.

Flotation Oxide Risk

Flotation is highly effective for sulfide-hosted gold but can struggle with oxide material. If the tailings contain a significant oxide fraction, flotation recoveries may drop.

However, this risk is manageable through:

• Reagent optimization
• Pre-conditioning
• Blending strategies
• Secondary scavenger circuits
• Hybrid flowsheets (e.g., flotation + gravity)

The key advantage is that flotation isolates the metallurgical risk into a small mass fraction, rather than exposing the entire tonnage to high-cost leaching.

Even in mixed oxide-sulfide systems, flotation-based flowsheets typically outperform CIP in both recovery and cost structure.