Radioactive elements in atmospheric precipitations of the Western Siberia

The radionuclide composition of the atmospheric precipitations (rain and snow) fell out on the territory of the South of the Western Siberia in 2016-2017 was studied. It is shown that, the maximum of deposition of Be and Pb were observed in a foothill zone (618 and 171 Bq/m), the minimum in the Alpine zone (104 and 27 Bq/m), for the forest-steppe zone these values are 237-340 Bq/m and 73-93 Bq/m. Deposition density of Cs in comparison with Pb and Be is small and does not exceed 1 Bq/m. Average values of total specific activities of Pb and Be in rain waters are 242 and 2434 mBq/l, in the snowmelt 506 and 1611 mBq/l. Be/Pb activity ratio in rain waters more than three times higher, than in snowmelt: 10,1 to 3,2. The highest values of Be/Pb activity ratios are observed in the finest fraction (<0.45 μm) of the suspended matter: 19 in rain and 10 in snowmelt waters.