Assessment of the Influence of BN-800 Operation on the Radioecological Situation in the Vicinity of Beloyarsk NPP

The aim of this work is to make an assessment of the dynamics of the radioecological conditions in the 30-km zone of influence of the Beloyarsk NPP after the commissioning of the BN-800 power-generating unit. Based on the established network of terrestrial ecosystems, it is shown that the operation of BN-800 did not increase the content of 90 Sr, 137 Cs, and 239+240 Pu in the soil and vegetation. The 137 Cs contamination density of the soil, as a rule, fluctuates in the range 5–8 kBq/m 2 . Exceptions are individual sections situated 3–10 km to the south-east of the NPP, where a gas-aerosol emission plume is dispersing. Here the 137 Cs contamination density is 2–3 times greater but these sections of the contamination were formed before BN-800 startup. The 90 Sr and 239+240 Pu contamination density ranges are, respectively, 1.1–2.5 and 0.08–0.16 kBq/m 2 , which fall within the limits of the fluctuations of the regional background level irrespective of BN-800 startup and distance from the reactor. It is shown that BN-800 emissions had no effect on the concentration of technogenic radionuclides in plants – the 137 Cs content is equal to 0.5–12 Bq/kg and 90 Sr to 1.4–19 Bq/kg.