Caspian Sea 2011

State of the Environment of the Caspian Sea

and other harmful chemical elements is transferred by wind to surrounding areas. There have been consistent readings of concentrations of chemi- cal elements and their compounds exceeding the maximum permissible levels - for fluoride by 130% and for phosphate by 180%. According to the eval- uation criteria, this signifies that the environmen- tal status of the area is hazardous. Underground dispersal and the release of polluted tailing water clearly pose a risk of contamination of ground and marine waters (Questionnaire KZ 2010). Over the years of uranium production, 356 mil- lion tonnes of mining waste with a total radia- tion level of 11 242 Curie was channelled into the Koshkar-Ata tailing pond. Uranium mill tailings with low- to medium-level radioactivity account for almost 105 million tonnes of the total. Signifi- cantly increased exposure rates of 80 to 150 micro roentgen per hour ( μ R/h) were measured in the southern part (UNEP/GRID-Arendal 2006). In Mangistau oblast, there are 19 enterprises which use radioactive substances during their production cycles. To date 17,694 tonnes of radio- active waste have accumulated in the oblast, not including the radioactive waste of the Koshkar-Ata tailing pit. For example, there are 5,000 tonnes of radioactive scrap metal stored in land areas con- trolled by the KASKOR Joint Stock Company, a chemical-hydrometallurgical plant (TACIS 2009). Alpha-active long-life radionuclides measure- ments were taken in the ambient air of the beach zone of Koshkar-Ata and Aktau city. These indicat- ed that maximum measurements of active aero- soles, equal to 0,041 Bq/m3 at the Koshkar-Ata tailing pit and 0,034 Bq/m3 within the precincts of Aktau city, were not harmful to humans. There are 19 oilfields with 1485 oil wells in the coastal zone of the Caspian Sea, including 148 in the flooded zone. These oil wells belong to the State (Baseline Inventory 2008). Only 24 flooded oil wells were sealed during the 2004-2006 pe- riod (CEP 2007a). Flooded oil wells are still an emerging environmental problem in Kazakhstan

(Questionnaire KZ 2010). Due to the rise in the level of the Caspian Sea, many coastal areas have become flooded, including the locations of oil wells. Drilling technology from the 1960s to the 1980s did not account for the corrosive na- ture of seawater and its effects on metal casings. Over time, these wells have become a consider- able source of marine pollution. Oil storage pits have also been listed among the emerging environmental problems in Kazakhstan. A number of major oil and gas deposits are lo- cated in Mangistau oblast. Their operation was followed by the construction of numerous earthen pits (barns) containing oil on these sites. There are 52 such pits with a total volume of 64,282.01 tonnes. In 2008, two storage pits were put out of use, with a total of 872.9 tonnes of oil pumped out and disposed of (Questionnaire KZ 2010). According to the Baseline Inventory, the to- tal volume of oil wastes in Mangistau oblast is 1,844,651 m 3 : in the Uzen oil field there is 1,419,234 m 3 of oil waste, in Zhetybai and Kal- amkas oil fields 343,125 m 3 and in Karazham-bas oil field 82,292 m 3 . Some of these oil wastes are used as construction material, paving roads and sites in the oil fields. In 2004, 468 m 3 of oil-soaked (‘masutted’) grounds were used in the Northern Buzachi oil field while 10,780 m 3 were used in the Karazhanbas oil field in 2005. In 2006, 8,478 m 3 of oil and drilling wastes were used as construc- tion material to pave roads inside the sites of the Northern Buzachi, Borankol and Tolkyn oil fields. A major by-product of oil production in Kazakh- stan is sulphur, which is used by many industries for manufacturing a wide range of products. Sul- phur is found, in varying amounts, in crude oil and natural gas. For example, the crude oil pro- duced by Tengizchevroil (TCO) contains “sour gas”, which has a hydrogen sulfide content of about 14 per cent. The company regularly sepa- rates sulphur from oil, with its current produc- tion amounting to about 1.6 million tonnes of sulphur per year. Sulphur production is expected to increase. Tengizchevroil has already built up a


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