The radioactive inventory of the solid wastes resulted from decommissioning of the VVR-S research reactor from Bucharest, Romania, is assessed and compared to the estimated one. The main part of the inventory is concentrated in the reactor block and hot cells. The reactor block inventory was estimated by preliminary measurements and calculation before decommissioning. The activated and contaminated structures were dismantled, cut, placed in containers and analysed by gamma ray spectrometry method. The dominant radionuclide was 60 Co identified in all dismantled components. By comparison of the activities measured in 2017 with those estimated in 2012 it can be noticed a good agreement between the estimations and the actual situation. The radioisotope production generated also a significant inventory at about 10.57 Ci.
The present study consists in the assessment of the dose rates potentially received by the workers involved in Hot Cells decontamination from a VVR-S type Nuclear Research Reactor under decommissioning. Two exposure scenarios were considered: the dosimetrist performing contamination scanning measurements (H*(10) inside of the Hot Cell prior decontamination and the mechanical worker performing floor decontamination. The dose rates were calculated based on the floor hot spots activity concentration using a standard and a numerical method (RESRAD Build code) assuming that the highest radiological risks are from these surfaces. It was noticed that the external dose rate is relatively high both for the floor scanning and decontamination and the internal committed effective dose is relatively low for floor decontamination due to fact that the worker is equipped with a high filter efficiency mask. By comparing the two methods results it is noticed that the dose rate obtained using the numerical method is 32% lower than the dose rate evaluated with the standard method, due to model complexity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.