Title: Estimation of deposit of natural radionuclides on the soil surface in the vicinity of Trypillya TPP

The purpose of research. Estimation of the loss of natural radionuclides as a result of emissions during the long-term operation of the Trypillya TPP.

Materials and methods of research. Trypillya TES is located 40 km south of Kyiv. To study the magnitude of radioactive fallouts caused by the Tripolskaya TPP, three pine forest areas were selected for 1.5 km, 1.8 km to the north and 3.0 km to the northwest north of the station, which correspond to the dominant wind directions. The investigated forest profiles of the surface included a layer of forest flooring and two layers of soil 5 cm in thickness each. To ensure the statistical accuracy of the results, 5 to 8 profiles were selected on each site. For comparison, we investigated forest profiles outside of the influence of thermal energy objects near the village. Yasnogorodka Vyshgorodsky district, about 60 km north of Kiev, or more than 100 km from the station. The forest floor samples were burnt to a compact shape, and the soils were dried in the air at room temperature for two weeks until a steady sample weight was reached. The radionuclide content was measured using the ORTEC Gamma Spectrometric System, which contains 3 precision pure germanium detectors and 919 multichannel buffers.

Research results. The results of the measurements showed that the value of the average aggregate level of precipitation of natural radionuclides on the surface due to regular emissions from the Trypillya TPP at a distance of 1.5-3 km is 34 50; 37 73; 48 66; 447 1216 Bq • m2 for 226Ra, 232Th, 238U and 40K. The corresponding maximum values ​​are at least twice as high: 63 125; 84,169; 103 180; 725 2430 Bq • m2 for 226Ra, 232Th, 238U and 40K. The predominant amount (80-95%) of activity of radionuclides is deposited in the upper 5 cm layer of soil, the rest - in the forest floor. The vast majority of 210Pb landings are of natural origin, where 55-95% belong to the upper layer of soil. Conclusions As a result of state emissions, the Trypillya TPP is enriched with natural radionuclides by the surface of the soil around the station. The maximum number of deposited radionuclides is concentrated in the upper 5 cm layer of soil, the rest - in the forest flooring. The study of forest soil profiles in the TPP impact zone provides information on the integral levels of natural radionuclides deposited on the surface during its period of activity. To obtain statistically weighted results, it is necessary to study 5-8 profiles. Keywords: Trypillya TPP, fossil fuels, coal, natural radionuclides, radioactive releases, radioactive deposition.

Trypilska Thermal Power Plant, fossil fuel, coal, natural radionuclides, radioactive releases, radioactive deposition

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