Many countries without nuclear power have only a small inventory of radioactive waste, primarily consisting of disused sealed radioactive sources (DSRS). Successful tests of a promising technology for the disposal of such sources have been recently completed in Croatia under the auspices of the International Atomic Energy Agency (IAEA). The method, which involves placing sources in stainless steel capsules and disposal containers and covering them with cement backfill in a narrow diameter borehole a few hundred metres deep, allows countries to dispose of their own DSRS safely and securely. Equipment tests conducted by IAEA engineers and a Croatian radiation protection company confirm the feasibility of a system used to move and insert low activity sources safely as part of borehole disposal.
This is the latest development in relating to the concept which Quintessa staff have supported over the last 14 years. In particular, Quintessa staff have taken the lead in developing a generic post-closure radiological safety assessment (GSA) for the borehole disposal concept and support its site-specific implementation in Ghana, Malaysia and the Philippines through IAEA expert missions and the provision of training courses. Richard Little has also contributed to the development of security documentation relating to the borehole disposal concept and is currently advising the IAEA on the development of a suite of associated technical documents.
AMBER has been used to carry out supporting calculations for the GSA, with the purpose of identifying the concept's key safety features, under varying disposal system conditions, in order to support the concept design and licensing processes, and facilitate its site-specific implementation. The GSA has been undertaken using an approach that is consistent with best international practice. Specifically, the ISAM safety assessment approach has been used, with the aim of ensuring that the assessment is undertaken and documented in a consistent, logical and transparent manner.
Disposal Containers for the Borehole Disposal of Disused Sealed Radioactive Sources
Images courtesy of the IAEA