Specific activity of radionuclides in Scots pine (Pinus sylvestris l.) wood on Stabatiškės site of Ignalina NPP

Abstract

A near surface repository for low and intermediate-level short-lived radioactive waste is being constructed on Stabatiškės site which is located in the territory of Visaginas Municipality near to Ignalina Nuclear Power Plant. If the specific activity of radionuclides in environmental objects were known before the construction of the repository, it would be possible to measure potential irradiance caused by the repository during its operation. This article researches the specific activities of natural (226Ra, 232Th, 40K) and artificial (137Cs) radionuclides in Scots pine (Pinus sylvestris L.) wood on the Stabatiškės site before the construction of the repository. Having measured the specific activities in the ashes of annual tree rings, the concentration and distribution of radionuclides in Scots pine wood was assessed. It was determined that there is no linear dependence between the change of pine biomass and the age of the tree. The change of biomass might have been caused by favourable and unfavourable climatic conditions and by atmospheric pollution. The article presents curves showing the interrelation of the change of pine biomass and specific activities of natural (226Ra, 232Th, 40K) as well as artificial (137Cs) radionuclides.