Characterization of Radioisotope and Shield Content of Stored Disused Sealed Radioactive Sources in Ghana

Abstract

Radioactive sources have been in use in Ghana over the last six decades, mainly in medicine, agriculture, industry, research, and academic investigations. Radioactive sources declared “disused” by users are required to be transferred to the Centralized Waste Processing and Storage facility of the National Radioactive Waste Management Center (NRWMC) located on the Ghana Atomic Energy Commission (GAEC) site in Kwabenya, a suburb of Accra. The NRWMC is the only national center mandated by regulation to receive and manage all radioactive waste in Ghana. A considerable number of radioactive sources received at the facility since its operation were without the necessary source information such as radionuclide, activity and reference date, identification number, supplier/manufacturer, etc. Sources received with information and those received without the proper information are both required to be properly characterized for the purpose of nuclear material accounting, segregation, pretreatment, conditioning and selection of appropriate management options and strategies. The risk associated with the management of disused sealed radioactive sources (DSRS) reduces considerably if the sources are conditioned. Characterization of DSRS immensely facilitates their conditioning. Radioisotopes and shield contents of DSRS stored in the Centralized Waste Processing and Storage facility of the NRWMC have been characterized. The protocol used for the characterization and the results are discussed in this paper.