Soil activity levels in the decommissioning area of a VVR-S nuclear research reactor

The paper presents the methodology for evaluating the levels of soil activity in the area possibly affected by decommissioning activities of the VVR-S Nuclear Research Reactor from Horia Hulubei National Institute for Research and Development in Physics and Nuclear Engineering, Romania. Gamma spectrometric analyses of the soil samples sampled from the surface and depth were carried out in order to obtain information about possible recent contamination from radioactive dust in the air as well as from unknown past “accidents”. The analysis was performed both before reactor decommissioning began (year 2006) and after its completion (year 2020) to demonstrate that the non-restrictive release criteria under the regulatory body regime for land from decommissioning area are met. Activity levels of anthropogenic and natural radionuclides do not exceed the exclusion levels imposed by the basic domestic safety standards in force. It can be stated that the reactor operation and decommissioning did not generate contamination of the surrounding soil.