Distribution of tritium and its compounds in the environment under normal conditions of operating of Kalininskaya nuclear power plant

Tritium is one of the most important dose-forming radionuclides that determine the radiation situation in the area where nuclear fuel cycle enterprises are located. At the same time, it is not possible to catch the tritium formed during the operation of a nuclear power plant using modern, efficient and cheap technologies. This causes an increase in its concentration in environmental objects and an increase in the contribution of technogenic tritium to the radiation load of the population. Therefore, the task of monitoring the formation of tritium during the operation of nuclear power plants, the content of tritium in emissions and discharges of nuclear power plants, as well as the distribution of this radionuclide in the environment is especially urgent today.

The study aims to analyze the environmental pollution due to emissions and discharges of tritium from the Kalininskaya nuclear power plant, the process of spreading tritium by air, as well as the accumulation of this radionuclide in water bodies, soil and food products grown in the area of the nuclear power plant.

The following methods, developed by the specialists of the Burnasyan Federal Medical Biophysical Center were used during the research: 1) "Method for determining the volumetric activity of organic and inorganic tritium compounds in water bodies by liquid scintillation spectrometry". 2) "Methodology for determining the concentration of organic and inorganic tritium compounds in the air of the environment and industrial premises". 3) "The method for determining the specific activity of tritium compounds in soil and vegetation" was developed and tested in the course of field studies at the Kalinin NPP. As a sample preparation we used the method based on burning a selected sample in a specialized Pyrolyser-6 Trio oven. All prepared counting samples were measured by liquid scintillation spectrometry on a counter Tri-Carb 3180TR/SL.

On the basis of an integrated approach to assessing the content of tritium and its compounds in air, water, soil and food, an analysis of the formation of environmental pollution due to emissions and discharges of tritium from the Kalinin NPP was carried out.

It is shown that the transport of emissions from the NPP by air and the wind direction prevailing in the territory of the NPP location have a significant importance in the formation of the contribution to the ingress of tritium into foodstuffs. The necessity of taking into account the ingress of tritium and its compounds with nuclear plant emissions into the environment in the task of optimization of radiation protection of the population under conditions of normal operation of NPP is shown.

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