International Cyanide（Sodium cyanide） Management Code - Gold Mine Acceptance Standards

In the gold mining industry, the International Cyanide Management Code has established a series of crucial acceptance standards regarding Cyanide management. These standards are of great significance for environmental protection and the well - being of wildlife.

1. Measures for High Cyanide Concentration in Reservoirs and Tailings Ponds

If the concentration of Weak acid soluble cyanide in the water of reservoirs and Tailings ponds exceeds 50 mg/l, Gold mines are obliged to take measures to prevent wildlife or livestock from approaching the water surface. Such measures may include setting up fences around reservoirs and tailings ponds, filling the water - logged areas with rubble, or covering them with nets.

2. Data Requirements for Cyanide Concentration

Gold mines should possess sufficient data to demonstrate that the concentration of weak acid soluble cyanide in their tailings ponds, heap leaching facilities, and solution ponds does not exceed 50 mg/L. This data is essential for ensuring the proper management of cyanide - containing liquids.

3. Prevention of Wildlife Mortality

Gold mines need to prove that when the concentration of weak acid soluble cyanide in open water is no greater than 50 mg/L, it can prevent the mass death of wildlife. This is an important aspect of maintaining ecological balance in the mining area.

4. Direct Discharge Standards

If a gold mine directly discharges wastewater into surface water, the concentration of weak acid soluble cyanide must not be greater than 0.5 mg/L. Additionally, the storage sites must be managed to prevent leakage, ensuring that the concentration of cyanide (weak acid decomposable cyanide) in the groundwater at and downstream of the site does not exceed the local groundwater environmental quality standards.

5. Mixed Zone Regulations for River Discharge

When discharging sewage into rivers, with the permission of regulatory authorities, a mixed zone of a certain length can be set up. However, the free cyanide concentration in the water downstream of the mixed zone must not be greater than 0.022 mg/L. Moreover, the gold mine is required to explain its measurement process.

6. Indirect Discharge Standards

For gold mines with indirect drainage, the free cyanide concentration in the water downstream of the mixed zone must not be greater than 0.022 mg/L.

These standards set by the International Cyanide Management Association play a vital role in regulating the gold mining industry's cyanide management, aiming to minimize the negative impacts on the environment and wildlife.