Refine your search:     
Report No.
 - 
Search Results: Records 1-2 displayed on this page of 2
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Role of soil-to-leaf tritium transfer in controlling leaf tritium dynamics; Comparison of experimental garden and tritium-transfer model results

Ota, Masakazu; Kwamena, N.-O. A.*; Mihok, S.*; Korolevych, V.*

Journal of Environmental Radioactivity, 178-179, p.212 - 231, 2017/11

 Times Cited Count:6 Percentile:31.3(Environmental Sciences)

Environmental transfer models assume that organically-bound tritium (OBT) is formed directly from tissue-free water tritium (TFWT) in environmental compartments. Nevertheless, studies in the literature have shown that measured OBT/TFWT ratios are variable. The importance of soil-to-leaf HTO transfer pathway in controlling the leaf tritium dynamics is not well understood. A model inter-comparison of two tritium transfer models (CTEM-CLASS-TT and SOLVEG-II) was carried out with measured environmental samples from an experimental garden plot set up next to a tritium-processing facility. The garden plot received one of three different irrigation treatments - no external irrigation, irrigation with low tritium water and irrigation with high tritium water. The contrast between the results obtained with the different irrigation treatments provided insights into the impact of soil-to-leaf HTO transfer on the leaf tritium dynamics. Concentrations of TFWT and OBT in the garden plots that were not irrigated or irrigated with low tritium water were variable, responding to the arrival of the HTO-plume from the tritium-processing facility. In contrast, for the plants irrigated with high tritium water, the TFWT concentration remained elevated due to a continuous source of high HTO in the soil. Calculated concentrations of OBT in the leaves showed an initial increase followed by quasi-equilibration with the TFWT concentration. In this quasi-equilibrium state, concentrations of OBT remained elevated and unchanged despite the arrivals of the plume. These results from the model inter-comparison demonstrate that soil-to-leaf HTO transfer significantly affects OBT/TFWT ratio in the leaf regardless of the atmospheric HTO concentration, only if there is elevated HTO concentrations in the soil. The results of this work indicate that assessment models should be refined to consider the importance of soil-to-leaf HTO transfer to ensure that dose estimates are accurate and conservative.

Oral presentation

Field testing and inter-comparison of advanced tritium transfer models

Korolevych, V.*; Le-Dizes-Maurel, S.*; Kwamena, N. O.*; Ota, Masakazu; Aulagnier, C.*; Patryl, L.*

no journal, , 

Participants of the Tritium (T) Work Group of IAEA MODARIA conducted blind testing of four models, TOCATTA of IRSN, CTEM-CLASS of CNL and SOLVEG of JAEA and CERES of CEA, against three field scenarios. Two field experiments were conducted in Canada: one at the Chalk River site by CNL and the other near a T light facility in Pembroke by the CNSC. The third field experiment was conducted near the La Hague processing plant, France. The diversity provided by three field campaigns and the similarity of modeled processes allowed us to determine the minimal complexity requirements of advanced T models. For each model scenario, predictions deviated from observations and revealed not only natural spatiotemporal variability of processes relevant to T transfer, but also intrinsic uncertainty of prediction. It is difficult to analyze the latter and proceed with model development before the natural variability is quantified, which require well instrumented field experiments.

2 (Records 1-2 displayed on this page)
  • 1