Sources and significance of variation in the dose estimates of Cl-36 biosphere transfer models: a model intercomparison study

作者：Bytwerk D^*; Limer L; Albrecht A; Marang L; Smith G; Thorne M

来源：Journal of Radiological Protection, 2011, 31(1): 63-82.

DOI：10.1088/0952-4746/31/1/004

A range of performance assessments have indicated that the long-lived activation product Cl-36 will be among the more significant contributors to dose following release to the biosphere from deep or near-surface repositories for radioactive wastes. Described here are results of a BIOPROTA model intercomparison study, investigating dose assessment uncertainties and variability on the basis of six Cl-36 models from three countries. The models share a compartmental approach with transfers between compartments handled on the basis of empirical transfer factors (IMARC, ERB2A, Aquabios), on the basis of defined specific activities (AquaCl36, SA_36Cl), or on a combination of these methods (MTA_Cl36). The dose estimates that these models produce for a consensus well-water irrigation scenario, as well as the effect of altering certain critical assumptions, are reported, and the causes of variation examined. For the scenario considered, the calculated doses are within a factor of 15 of each other. Major differences were attributable to the data used for stable Cl concentrations and Cl-36 transfer parameter values, both typically site-specific parameters. Additional critical assumptions were studied such as the impact of stable chloride in the diet on dose coefficients, the effect of irrigating pasture with contaminated water on Cl-36 concentrations in animal products, and the explicit consideration of foliar uptake.

• 出版日期2011-3