2.3.3.4 Pre-operation safety analysis report

The pre-operation safety report (POSAR) was drafted based on internationally recognized standards. The overall concept was based on US NRC RG 1.70, for accident analyses representing part of this report, the IAEA document ”Guidelines for Accident Analysis for WWER Nuclear Power Plants” was used, while respecting the applicable Slovak legislation. Based on positive assessment of POSAR as well as based on reviews conducted by ÚJD inspection teams in terms of ČSKAE Decree No.6/1980 on securing of nuclear safety during start up and operation of nuclear power generating installations, ÚJD granted its approval with the commencement of physical and energetic start up of units one and two. After the start up of unit 2 , the initial and actual parameters of unit 2 were compared at ÚJD request, based on the results of inactive and active tests. Based on this analysis procedures for POSAR amendments was agreed. The comparison has been incorporated into PoBS. The most important amendments resulted from the use of profiled fuel, and chapters concerning reactor physics (chapter 4) and accident analyses (chapter 15) were reviewed in cooperation with the supplier of the new fuel. Chapters 4 and 15 of POSAR were completely replaced. Any changes and amendments made to POSAR in connection with the completion of the implementation of safety measures during the operation of the units are being continuously submitted to ÚJD for review, and incorporated into POSAR as revisions of the individual chapters so as to provide for updated POSAR. Total revision of POSAR will be made in accordance with the applicable standards after ten years of operation.