Lake Koshkar Ata extends on the area of approximately 50 km2, 5 km from the outskirts of the Aktau city and 8 km from the shore of the Caspian Sea. During the Soviet era the uranium deposits have been found in Kazakhstan. In 1980s Kazakhstan was producing more than one third of Soviet uranium, with more than 30 uranium mines. The former Koshkar Ata depression was chosen as a convenient location to accumulate radioactive and toxic waste from the chemical and hydrometallurgical complex in the newly-founded city of Shevchenko, now Aktau, with about 176 thousands inhabitants. Southern part of the lake is thus exposed to radioactivity. Uranium mining stopped in 1999 due to changes in military priorities. However, the lake in some cases is used as a dumping ground for commercial and production waste, oil extraction sludge etc. Pipelines from several other facilities lead to the lake and the lake borders are mostly covered by enormous dump. As the Mangystau land is short on water, the animals such as horses and camels come here to drink. Their milk and meat might get contaminated by mixture of chemicals.
High evaporation and lack of water may possibly cause that the lake will dry out in future. Southern part (around 13 km2 of soil), the part of the highest concentration of contaminants, solid waste and high levels of radioactivity, is already exposed to the air. Due to the strong winds, omnipresent in the area, the dangerous pollutants may disperse at a long distance.
The local authorities are more concerned about a possible contamination of the Caspian Sea, since the pollutants might migrate through groundwater. However, there is no hard evidence that the Sea has been affected. According to monitoring, elevated levels of contamination in the groundwater and soil are currently limited to a 2-4 kilometers wide strip around the lake.
