The dispersion of 137Cs in a shallow Mediterranean embayment (Saronikos Gulf--Elefsis Bay), estimated inventories and residence times.
The activity concentrations of (137)Cs in the water column of the Saronikos Gulf and Elefsis Bay (Greece) determined during four cruises between winter 2007 and winter 2009 are evaluated in the present study. The activity concentrations of (137)Cs ranged between 1.0 ± 0.3 and 6.5 ± 0.7 Bq m(-3) (mean: 2.7 ± 1.6 Bq m(-3)), depending on sampling depth and season with a tendency to background levels. Regarding the vertical distribution of (137)Cs, maximum concentrations were observed in the interface between water and sediment during autumn and winter as a result of thermocline break-down at the end of winter that caused surface (137)Cs to sink into deeper layers. The mean surface residence time of the Chernobyl-derived (137)Cs in the Saronikos Gulf was estimated to be 15 ± 4 y, whereas the effective and the ecological half-lives of (137)Cs in the study area were 6.2 ± 1.5 and 7.8 ± 1.9 y, respectively. Finally, the inventories of (137)Cs varied between 0.052 ± 0.004 and 1.315 ± 0.129 kBq m(-2) (mean: 0.355 ± 0.302 kBq m(-2)), being in the lowest level comparing to the direct atmospheric deposition after the Chernobyl accident.
NCSR Demokritos, Institute of Nuclear Technology-Radiation Protection, Environmental Radioactivity Laboratory, 15310 Agia Paraskevi, Athens, Greece. nevag@ipta.demokritos.gr
Nikolaos
N
Evangeliou
Heleny
H
Florou
D002588:Cesium Radioisotopes / Q000032:analysis*; D011847:Radioactive Fallout / Q000032:analysis*; D012621:Seasons; D014875:Water Pollutants, Radioactive / Q000032:analysis*
D002588:Cesium Radioisotopes; D011847:Radioactive Fallout; D014875:Water Pollutants, Radioactive