Methodological developments and practice in characterisation of unconventional and legacy waste

Strand, P.*; Jefferies, N.*; Koma, Yoshikazu  ; Plyer, J.*

Radioactive waste management requires the characterisation process to underpin the decisions that need to be taken to manage the waste safely. This paper reviews experience of characterisation of waste generated from past nuclear activities that were not conducted in compliance consistent with current criteria, or from unexpected situations that were not planned for. The development of a reliable and efficient characterisation and categorisation methodology is a common challenge for unconventional and legacy waste. Through the activities of the Nuclear Energy Agency Expert Group on the Characterisation of Unconventional and Legacy Waste (EGCUL), consideration has been given to widely used waste stream characterisation procedures and methods that were originally developed primarily for application in conventional decommissioning work. By analysing the challenges and lessons learned, it has been possible to identify opportunities for adaptations and enhancements to these characterisation methodologies, and these are set out and explained.