Quantitative prediction of dynamic HTO migration behavior in the soil and non-negligible evapotranspiration effect

• Published in: Journal of hazardous materials 2022-03, Vol.425, p.127772-127772, Article 127772
• Main Authors: Nie, Baojie, Wu, Siyuan, Yang, Derui, Chen, Deyi, Gu, Weiguo, Zhou, Wentao, Yin, Junlian, Wang, Dezhong
• Format: Article
• Language: English
• Subjects: Evapotranspiration; Migration; Nuclear power plant; Plant Leaves - chemistry; Radiation Monitoring; Root water uptake; Soil; Soil Pollutants, Radioactive; Tritium
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.127772

Tritium is mainly produced from nuclear facilities apart from nuclear tests. After being released to the environment, tritium would cause water & food contamination due to its radioactivity and mobility. This study investigated dynamic characteristics of tritiated water (HTO) migration in the soil and evapotranspiration effect based on realistic environmental conditions. The influences of soil types and time-varying environmental factors such as precipitation and evapotranspiration on tritium migration behaviors were specially discussed under normal continuous and accidental short-term release conditions. Radiation dose caused by dynamic tritium evapotranspiration was evaluated. The results show that tritium migration velocity in the soil is much higher than other particles such as cesium due to negligible adsorption of tritium by the soil. Tritium migration in the soil from up to down is attributed to precipitation. On the contrary, evapotranspiration factor would carry tritium movement along the opposite direction. A considerable fraction approximately 55% of tritium deposited in the soil would be reemitted into the air from bare soil and plant leaves due to evapotranspiration effect. Subsequently, the radiation dose caused by second plume due to evapotranspiration effect might be higher than the first plume due to direct release from the nuclear facility under routine discharge. [Display omitted] •Dynamic tritium migration characteristics in the soil were investigated.•Dynamic tritium transfer characteristics through plant root uptake were explored.•Tritium migration velocity vector is attributed to precipitation and evapotranspiration.•The question where the tritium in the soil has gone was first real-time quantitatively answered.•A numerical method describing dynamic tritium behaviors in air-soil-plant system was introduced.