Overall examination of the ecological situation in the toxic and radioactive wastes storage 'KOSHKAR-ATA' and development of rehabilitation actions

The operation of chemical-technological, mining and metallurgy plants in Mangyshlak (Kazakstan) caused deterioration of ecological conditions in Mangystau region, where tailing "KOSHKAR-ATA" is considered as the most hazardous object. Storage "KOSHKAR-ATA" is an internal-drainage sedimentation lake for toxic, radioactive and industrial chemical wastes (TR W) and for domestic wastes. It is located 5 km northward to Aktau town, situated on the Kaspean Sea shore. Since 1965, all TRW have been stored in "KOSHKAR ATA " up to now. At present, real mass of them is 360 mln. tonnes and total activity is about 11000 Ci.Under local hydro-technical conditions, liquid wastes have a tendency to spread in underground water horizon and Caspian Sea. Results of well highaccuracy thermometry (1992-93) show sufficient distortion (to 1°C and more) of geo-normal field at the territory of tailing "KOSHKAR-ATA". When the investigation of the tailing was in progress, warm water was flowing in west direction (4-4,5 Km) and in some places reached Caspian Sea coast. Due to continuous contamination of the soil and vegetation around "KOSHKAR-A TA" storage regional ecological conditions become critical. Consequently, some measures have to be taken immediately in order to eliminate source of contamination, contain the spread of contamination and rehabilitate the environment. The experience acquired during the assessment of the storage of toxic and radioactive wastes "KOSHKAR-ATA" can be applied to territories with similar ecological problems. With development of deposits of uranium ores, oil, mineral and establishment of chemicalengineering manufactures at Mangyshlak Peninsula at the beginning of 1960 in conditions of environmental issues ignoring there was laid the current degradation of ecological situation in Mangistau region (Kazakstan). The degradation is caused by number of extremely bad ecological objects. The most harmful object from the ecological point of view is Koshkar-Ata tailing dump. It causes the significant atmosphere contamination by radioactive and toxic wastes dust of chemical and mine metal productions presenting serious danger for health of inhabitants of Aktau-city and neighboring settlements [1,2]. The purpose of this researches is to study current ecological situation in the territories, adjacent to the tailing pond KOSHKAR-ATA and to develop rehabilitation actions, taking into consideration local soil-climatic peculiarities. The tailing pond KOSHKAR-ATA, representing the drain-free settling pool for industrial, toxic, chemical and radioactive wastes, and for ordinary domestic drains, is 5 km northward to Aktau (Mangystau region), which is situated on the shore of the Caspian sea. Industrial, toxic and radioactive wastes, solid sediments of unpurified ordinary domestic drains form a part of the Aktau dwelling region have been placed in tailing pond since 1965 and have been stored there up to now. Till 1965, tailing pond KOSHKAR-ATA was a drain-free hollow with 38 m initial depth.