Decommissioning cost evaluation for Korean Nuclear Power Plants

A systematic study was performed to develop decommissioning cost evaluation technology and to establish optimum decommissioning plan for Korean nuclear power plants. Eight decommissioning options for Kori unit I including DECON, SAFSTOR and ENTOMB were considered for detailed cost analysis. Immediate and delayed dismantling scenarios were compared each other in regards to economic, technical and social aspects. Fourteen decommissioning unit activities were considered in estimating unit cost factors including labor cost, consumables cost and equipment cost. The decommissioning cost for Kori unit 1 was lowest for DECON option and highest for ENTOMB-3 option in which the site recovery was made after entombment of 300 years. The main cost of the SAFSTOR option resulted from the dismantling and extended safe storage. For a long decommissioning period, the discount rate is crucial in estimating the decommissioning cost. The difference among decommissioning options was negligible in cost if a discount rate of 2% was assumed. The long-term safe storage option also became advantageous relative to the immediate dismantling option as the discount rate increased. (author)