Reconstruction of the Contamination and Purification of White Sea Water to Remove Global 90Sr

Abstract

Contamination with 90Sr of the White Sea water in migration during 50 years is reconstructed with the use of a three-component exponential model. Т1, Т2, and Т3, the periods of half-purification of White-Sea water to remove 90Sr were 0.8, 15.4, and 29 years, respectively. During 50 years of migration, the content of 90Sr in water decreased from 41 to 2–3 Bq/m3. The maximum decrease in the content of 90Sr was observed in 1965–1968. The outflow of 90Sr in 1970 from the White Sea was 37.5, and the inflow with Barents-Sea water, 25.5 TBq. The outflow was partly compensated for by the inflow of 4 TBq of 90Sr with water of the rivers Northern Dvina, Onega, Mezen’. The White Sea water is a weak source of 90Sr for the Barents Sea. The inflow of global 90Sr with the river flow makes slower the replacement of the more contaminated White Sea water with the purer water of the Barents Sea. The determinations of 90Sr in the White Sea water (1965–2015) in terms of the exponential model have been confirmed by the results of experimental observation of 90Sr in the sea bays. During 50 years, 1.5–2 times higher concentrations of 90Sr were preserved in the semi-closed White Sea, compared with the Barents Sea.