Description:
The Ok Tedi mine is located high in the rain forest covered Star Mountains of Papua New Guinea. Prior to 1981 the local Wopkaimin people lived a subsistence existence in one of the most isolated places on earth. That was before the 10 000 strong town of Tabubil suddenly appeared in the middle of their community. The Ok Tedi mine was built on the world’s largest gold and copper deposit (gold ore capping the main copper deposit). From the very beginning things did not go according to plan. It was originally envisaged that the mine tailings would be stored in a dam, and after the settling of solid particles, clean water would flow down the Ok Tedi River, then into the Fly River for the 1 000 km journey to the sea. It would have been an engineering marvel to build such a dam on the side of a mountain where it rains more than 10 meters a year and earthquakes are common. The half-built tailings dam collapsed in 1984 and the mine went ahead without a waste disposal plan... Without the tailings dam, riverine disposal of waste was the only option. The tailings are composed of fine-grained rock containing traces of copper sulphide and residual cyanide. The build up of tailings in the lower Ok Tedi has caused a rise in the river-bed, flooding and sediment deposition on the flood plain, leading to a smothering of vegetation (“dieback”). To date, about 1300 square kilometres of dieback has been observed. Up to 2040 square kilometres of forest may ultimately be affected. These forests are expected to take many years to recover after mine closure.