Consider of Verfication Methodologies for the Initial Core and An Experienc eof National Verification for Transfer Campaign in OLR

Initial core verification in the On-Load Reactor is important in light of the continuity of knowledge of safeguards. Considering the difficulties of verifying the core fuel in a manner of fundamental measure after connecting into the electrical grid, a safeguards approach on the initial core should be established and applied in accordance with a philosophy or concept of safeguards. The safeguards consistency should be maintained even though any approach is adopted among several alternatives. Furthermore, the emphasis should be placed on the effectiveness of safeguards applications rather than cost savings or the reduction of inspection efforts. One of the major characteristics differentiating the On-Load Reactor from the other types of power reactors is that the transfer campaign should be performed approximately from the tenth year of commercial operation. A transfer campaign has been carried out every year for a period of two months or so and several instruments developed by the SSAC were applied to the verification activities in 1998. Through experience of the transfer campaign, the necessity of equipping the spent fuel bay with additional containment and surveillance measures was identified so as to carry out efficiently verification of the transfer campaign in terms of national inspections.