Disposal is the final phase for sealed radioactive sources when they have reached their end of life and are declared radioactive waste. However, disposal is not an easy task, because selecting the type of disposal facility depends on multiple factors, such as the type and quantity of radioactive waste; the existing and future environmental, geological, seismic and climate conditions; and available funds. For countries with limited amounts of radioactive waste, disposal could theoretically involve safe, secure and permanent placement inside boreholes, deep underground.
The IAEA is providing technological and engineering support for the first of a kind construction and implementation of borehole disposal facilities for radioactive waste, as part of a pilot project underway in Malaysia and Ghana, funded by Canada.
“The borehole system allows for a permanent disposition, rather than storage, solution,” said Heather Looney, Head of the Nuclear Security of Materials and Facilities Section at the IAEA’s Division of Nuclear Security. “One of the most important benefits expected from this project is the overall enhancement of nuclear security and radiation safety at the national and regional level, as well as globally. The IAEA systematically assists countries to identify and implement optimal solutions for the safe and secure use, storage, and now permanent disposal of their radioactive sources.”
Sealed radioactive sources are important for many nuclear applications in industry, medicine, agriculture and research. Their uses include treating cancer, extending food shelf life, sterilizing medical supplies, irradiating seeds to enhance food production, supporting oil and gas prospecting, measuring soil density for construction and in common smoke detectors. A cradle-to-grave management approach to radioactive sources recognizes that a radioactive source continues to require safety and security arrangements after the end of its use, and ensures such continuous safety and security.
“The borehole disposal is a fit-for-purpose and cost-effective solution in general, because it is specifically designed for disposal of disused sealed radioactive sources (DSRSs) and is economically affordable in comparison with the other disposal pathways, such as geological disposal,” said Nora Zakaria, Head of the IAEA Waste Technology Section.