Justification of radiological criteria for the use of areas with residual radioactive contamination based on the dose approach
The article presents a methodology for assessing the radiological criteria for the use of the territory (a land plot with buildings) with residual radioactive contamination from the so-called "green area", i.e., complete release from radiation control until a number of restrictions are imposed on the use of the territory. In accordance with the further use of the territory, a range of scenarios and pathways for the exposure of the population was considered. A set of models and their parameters, corresponding to the number of the considered pathways of exposure, was defined. Assuming a uniform distribution of a radionuclide with a unit concentration in the source zone, the distribution of effective doses for the population living in the territory with the residual radioactive contamination for different irradiation scenarios was calculated by stochastic modeling, 95% of the quantile of which was attributed to the dose in the representatives of the critical population group. Next, the value of radiological criteria, depending on the implemented scenario, was determined as the ratio of the dose constraint EL = 0,3 mSv/yr and 95% quantile in the distribution of the effective dose from a unit contamination. The numerical values of radiological criteria for the presence of radionuclides in the soil are presented, both for the radiation scenarios that correspond to the permanent residence of the population in the contaminated territory and for recreational use. A further consideration is given to the so-called worker scenario, which corresponds to the limited time spent on the contaminated territory and the simultaneous effects of radionuclides contained both in the soil and in the construction of the buildings. A comparison of the results of the own calculations with the data of other authors was carried out.