DECOMMISSIONING COSTING APPROACH BASED ON THE STANDARDISED LIST OF COSTING ITEMS; LESSONS LEARNT BY THE OMEGA COMPUTER CODE

摘要

The document "A Proposed Standardised List of Items for Costing Purposes" [1] was issues in 1999 by OECD/NEA, IAEA and European Commission (EC) for promoting the harmonisation in decommissioning costing. It is a systematic list of decommissioning activities classified in chapters 01 to 11 with three numbered levels. Four cost groups are defined for cost at each level. Document constitutes the standardised matrix of decommissioning activities and cost groups with definition of content of items. Knowing what is behind the items makes the comparison of cost for decommissioning projects transparent. Two approaches are identified for use of the standardised cost structure. First approach converts the cost data from existing specific cost structures into the standardised cost structure for the purpose of cost presentation. Second approach uses the standardised cost structure as the base for the cost calculation structure; the calculated cost data are formatted in the standardised cost format directly; several additional advantages may be identified in this approach. The paper presents the costing methodology based on the standardised cost structure and lessons learnt from last ten years of the implementation of the standardised cost structure as the cost calculation structure in the computer code OMEGA. Code include also on-line management of decommissioning waste, decay of radioactivity, evaluation of exposure, generation and optimisation of the of the Gantt chart of a decommissioning project, which makes the OMEGA code an effective tool for planning and optimisation of decommissioning processes.