Effectiveness of unannounced inspection and its practicability

The IAEA presented at the Board of Governor that an Unannounced Inspection (hereafter UI) was expected as an effective safeguards measures to LWRs and DNLEU facilities that handles the less sensitive nuclear material. The possibility on the application of UI has been stated in INFCIRC/153(corrected) as one of inspection mode. However, due to difficulties to provide suitable conditions to implement UIs, it is unusual for them to be practical. Under the integrated safeguards, safeguards levels for the less sensitive nuclear material will be one level reduced based on the conclusion that the IAEA could not find any fact and evidence to indicate the undeclared nuclear material and activity in the State. As promising safeguards measures, implementation of UI is noticed because UIs may have a lot of effects such as unpredictability and deterrence. We discuss the effectiveness of UI and its practicability through the comparison with the SNRI and the LFUA that is applied to DNLEU handling facilities and the cascade hole of uranium enrichment facilities, respectively, after introducing the proposed UIs to LWRs. (author)