Development of public exposure scenarios for land sites with residual radioactive contamination

The article considers the experience of development of public exposure scenarios for land sites with residual radioactive contamination on the example of three sites located in Moscow and St. Petersburg. The study was intended to identify the anticipated groups of land users and select parameters for calculating radiation doses. Exposure scenarios regarding use of land sites for living or working were described by such parameters as duration of the stay, staying indoors or outdoors, physical activity, etc. Exposure pathways for selected users were identified using the conceptual site model approach. For calculations within a number of scenarios, geomigration modeling of radionuclide transport in the environment was performed using the GeRa code. Exposure doses for population groups were calculated using the Ecorad-Aqua software module. Doses were calculated for each exposure pathway. The study demonstrates that the proposed scenario “Office worker” can be applied to various sites that are planned for placing administrative, industrial, scientific, commercial buildings and structures, scenario “Construction worker” – for sites with construction and excavation activities underway. The parameters of the “Resident” scenario allow for its application for the multiapartment residential development in large cities. In the future, it is practical to develop a typical scenario for an outdoor worker whose activity is to provide care and maintenance of the site. These scenarios can be used as ready-made solutions for calculating radiation doses for the population from residual radioactivity at the nuclear sites under decommissioning and remediated areas. Estimates of annual effective doses for the population are needed for decommissioning and remediation planning and determination of the values of radiation factors in the relevant projects.