SEDIMENT RADIONUCLIDE PROFILES - IMPLICATIONS FOR MECHANISMS OF SELLAFIELD WASTE DISPERSAL IN THE IRISH SEA

被引:56
作者
MACKENZIE, AB
SCOTT, RD
ALLAN, RL
BENSHABAN, YA
COOK, GT
PULFORD, ID
机构
[1] Scottish Universities Research and Reactor Centre, East Kilbride, Glasgow
[2] Agricultural, Food and Environmental Chemistry, University of Glasgow, Glasgow
基金
英国自然环境研究理事会;
关键词
Irish Sea - Radionuclides - Scotland - Waste dispersal;
D O I
10.1016/0265-931X(94)90504-5
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Evaluation of the radiological significance of Sellafield waste radionuclide discharges to the Irish Sea requires characterisation of redistribution processes affecting contaminated marine sediment, and investigations of sediment radionuclide concentration profiles are often used in this context. Results are presented here for a study of radionuclide concentrations in saltmarsh sediments in south-west Scotland, which provide a record of Sellafield waste radionuclide deposition since the 1960s. Comparison of the results with data for the Sellafield discharge and other sediment studies indicates that the dominant mechanism of transport of Sellafield waste to the study sites involves redistribution of contaminated silt. It is also observed that the sediment profiles preserve a record of the time-integrated Sellafield discharge rather than of the annual variations. Temporal variations in sediment radionuclide concentrations are explained in terms of a simple model which includes the effects of dispersion/dilution of this contaminated silt and of radionuclide redissolution. It is concluded that, provided Sellafield discharges do not increase substantially, continuation of these processes will result in a decrease with time of pollutant radionuclide concentrations in the sediment being deposited, but in an increase in radionuclide inventories in accumulating Irish Sea intertidal and saltmarsh sediments.
引用
收藏
页码:39 / 69
页数:31
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