Assessment of the level of annual intake of tritium into the air from the surface of the lake Kyzyltash

Abstract

Сайт «Озёра России». URL: https://ozera.info/lakes/ about/gvr/list-lakes/kyzyl-tash (Дата обращения 25.03.2022 г.) Екидин А.А., Антонов П.Л., Жуковский М.В. Оценка загрязнения атмосферы тритием при испарении воды с поверхности промышленных водоемов // Вопросы радиационной безопасности. 2012. № 3. С. 3-10. Андреева М.А. Озера среднего и Южного Урала. Челябинск, 1975. 270 с. Толстикова В.С. Кузнецов В.Н. Ядерное наследие на Урале: исторические оценки и документы. Екатеринбург, 2017. 400 с. Баторшин Г.Ш., Мокров Ю.Г., Алексахин А.И. Концепция вывода из эксплуатации водое мов-хранилищ ЖРО ФГУП «ПО «Маяк». VII Международный промышленный форум «АТОМЭКО – 2013». М., 2013. Радиационная обстановка на территории России и сопредельных государств в 2020 г. Ежегодник. Обнинск, 2021. 239 с. Чеботина М.Я., Николин О.А., Смагин А.И., Мурашова Е. Тритий в водоёмах производственного и комплексного назначения в районе ПО «Маяк» на Урале // Водное хозяйство России. 2011. № 4. С. 75-84. Vostrotin V.V., Yanov A.Y., Finashov L.V. Tritium in environmental objects in the area affected by FSUE Mayak Production Association in 2014-15 // Journal of Radiological Protection. 2021. Vol. 41, № 2. P. S56-S66. DOI 10.1088/1361-6498/ abe8c8. Иванов Н.Н. Об определении величины испаряемости // Известия Всесоюзного географического общества. 1954. Т. 86, № 2. вып. 1. С. 189–196. Сайт компании ООО «Расписание Погоды». URL: https:// rp5.ru. (Дата обращения 25.03.2022). Busigin A., Kalyanam K.M., Sood S.K. Estimation of the tritium release rate from a spill of tritiated water // Fusion Technology. 1992. Vol. 21, No 2P2. P. 512-517. DOI: 10.13182/FST92-A29798. Yoshinori S. Lake water mixing and tritium balance in lake Chuzenji // Geographical Review of Japan. 1983. Vol. 56-10. P. 667-678. The paper presents the results of research of the levels of tritium volume activity in lake Kyzyltash, a water storage reservoir for liquid radioactive waste from Mayak Production Association. Insufficient knowledge of the ways of migration of tritium from the reservoir and their quantitative assessment in modern conditions does not allow to fully objectively assess and predict the impact of the object of “nuclear heritage” on the population of Ozersk and the environment. The research was aimed at obtaining scientific results, which will be the starting point for the formation of a tritium monitoring program for industrial reservoirs by Mayak Production Association. The purpose of the study was assessement of the dynamics of tritium volume activity in the lake Kyzyltash, assessment of water balance parameters and the level of tritium intake into the air from its surface during the ice-free period. A total of 33 water samples were collected. The average tritium volume activity in 2021 made 1,57Е+04 Bq/l, SD – 1,1Е+03 Bq/l that more than 2 times exceeds the intervention level. A trend of decrease in the average monthly tritium volume activity in the reservoir during the observation period was revealed. In the course of calculations, it was stated that in the course of evaporation during the ice-free period the 196 TBq of tritium entered the air from lake Kyzyltash surface that is comparable with releases from all the Russia facilities (179 TBq) except Mayak Production Association. The obtained values of evaporated tritium make 13% from atmospheric tritium releases of Mayak Production Association in 2020. A total of ~12,2 million m3 had evaporated from the water reservoir surface in the study period. The model of dependence of tritium volume activity from time in lake Kyzyltash in 2021 and using of exponentially decreasing function allowed defining water balance of lake Kyzyltash in the ice-free period with 6,3 million m3 deficiency. Research of the model parameters allow prediction of sanitary and hygienic characteristics of the water reservoir from the point of view of radiation safety and calculation of water balance of the reservoir in certain periods of time.