Gold mine tailings ponds

The breached tailings pond at the gold mine, which was 93 ha in area and about 20 m deep, was lined with a plastic membrane and held approximately 4.43 million tons of flotation solid wastes. Due to an imbalance between water burden, unexpected quantities of water from the addition of snow and rain, and safe storage volume, the capacity of the pond was insufficient to safely store the slimes. It was estimated that 50 to 100 tons of cyanide were released into the river (UNEP/OCHA, 2000). 

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