The density of radioactive fallout was varied in different area of the Black Sea
and in coastal area the
239þ240 Pu average fluxes ranged from 1.08 to 3.813 Bq m
À2
year
À1 . It depended on the
239þ240 Pu concentration activity in the water and SR
which ranged from 2 to 6 mm year
À1 in Sevastopol sea area and that was significantly higher than SR in open area. The depth distribution of the
239,240 Pu concentration activity of the Black Sea bottom sediment in Sevastopol sea area is
presented in Fig. 16.6 (Tereshchenko et al. 2016). The maximum of the Chernobyl
fallout was on depth about 7–8 cm, it was deeper than in open area 2.7 times and the
239þ240
Pu fluxes in that time were 2.27 Bq m
À2 year
À1 for maximum of the
Chernobyl fallout. In this layer the ratio of
238 Pu/
239þ240 Pu was equal 0.036 that
exceeded this ratio in global fallout only about 2 times. In period of maximum of
the Chernobyl and global radioactive fallout the
239,240 Pu concentration activity of
the Black Sea bottom sediment in open area was higher than in coastal area, but the
contaminated layers are lower several times.
16.3.7 Plutonium Radiocapacity Factor of Bottom Sediment
Integral characteristic to evaluate a role of bottom sediment in the redistribution of
the radionuclide in the water ecosystems is radiocapacity, as a measure of the
ability of sediment to accumulate and retain radioactive substances, originally
Fig. 16.5 Depth
distribution of the
239,240
Pu
concentration activity of the
Black Sea bottom sediment
in open area and maximum
of the global (1962–1963)
and Chernobyl (1986–1988)
fallout
262
N.N. Tereshchenko
and in coastal area the
239þ240 Pu average fluxes ranged from 1.08 to 3.813 Bq m
À2
year
À1 . It depended on the
239þ240 Pu concentration activity in the water and SR
which ranged from 2 to 6 mm year
À1 in Sevastopol sea area and that was significantly higher than SR in open area. The depth distribution of the
239,240 Pu concentration activity of the Black Sea bottom sediment in Sevastopol sea area is
presented in Fig. 16.6 (Tereshchenko et al. 2016). The maximum of the Chernobyl
fallout was on depth about 7–8 cm, it was deeper than in open area 2.7 times and the
239þ240
Pu fluxes in that time were 2.27 Bq m
À2 year
À1 for maximum of the
Chernobyl fallout. In this layer the ratio of
238 Pu/
239þ240 Pu was equal 0.036 that
exceeded this ratio in global fallout only about 2 times. In period of maximum of
the Chernobyl and global radioactive fallout the
239,240 Pu concentration activity of
the Black Sea bottom sediment in open area was higher than in coastal area, but the
contaminated layers are lower several times.
16.3.7 Plutonium Radiocapacity Factor of Bottom Sediment
Integral characteristic to evaluate a role of bottom sediment in the redistribution of
the radionuclide in the water ecosystems is radiocapacity, as a measure of the
ability of sediment to accumulate and retain radioactive substances, originally
Fig. 16.5 Depth
distribution of the
239,240
Pu
concentration activity of the
Black Sea bottom sediment
in open area and maximum
of the global (1962–1963)
and Chernobyl (1986–1988)
fallout
262
N.N. Tereshchenko