Experts from 15 Member States, including Richard Little from Quintessa, recently attended a technical meeting at the International Atomic Energy Agency (IAEA) in Vienna to examine suitable strategies for the disposal of disused sealed radioactive sources (DSRS) and assessing the safety of disposal facilities for DSRS declared as waste. Participants discussed the status of DSRS management in Member States, the Code of Conduct Guidance on Management of DSRS, the development of safety cases and safety assessments for disposal facilities, and areas for possible future work.
Radioactive sources are used for many beneficial purposes in areas such as health, industry, research and agriculture. At the end of their lives, sealed radioactive sources that will not decay rapidly to safe levels (e.g. within a few weeks) and cannot be recycled, returned to their manufacturers, or transferred to another national programme need to be disposed in the country of their use. IAEA safety standards recognise three disposal options: near surface disposal, borehole disposal, and geological disposal.
DSRS typically have small volumes, but very variable, and sometimes exceedingly high levels of radioactivity. Some short-lived and lower-activity DSRSs may be disposed in near surface disposal facilities, but others require greater degrees of isolation and containment – this can be achieved through borehole disposal or geological disposal.
The meeting identified several areas of possible further work including, more formal review of information on the acceptance of DSRS at disposal facilities in Member States, work on the development of “reference” scenarios for assessing the impacts of disposing DSRS in near surface disposal facilities, development of guidance on how to derive waste acceptance criteria for DSRS storage and disposal, and work on how to manage existing facilities where DSRS have been mixed with other radioactive waste.
Lead Image: Radioactive waste and disused sealed radioactive sources that need to be retrieved from an old facility for safe management. (Photo courtesy of V. Ognerubov, Ignalina NPP, Lithuania)