2.1.2.2  NPP V-1 safety analysis reports

The initial safety analysis report

The initial safety analysis report was drafted in 1978 as a document entitled “NPP V-1 Pre-Operation Safety Report“. Its structure and contents accounted for the requirements of the amended version of the document „Guidelines for the Setting up and Contents of Safety Reports“ issued by ČSKAE in 1977, extended by the following chapters:
- Principal Criteria
- Operation Limits and Conditions for NPP V-1 unit 1.

Later amendments to the initial Pre-Operation Safety Analysis Report

An amendment was made in 1990 to replace the chapter „Safety Analyses“ of the initial report, due to the existence of more modern computer codes and in connection with some changes in „opinions“ concerning approaches to nuclear safety. Within the amendment, chapters were drafted to replace chapter V „Safety Analyses“.

In connection with the „small“ reconstruction of NPP V-1 units in preparation, a solution was adopted according to which no other chapters of the initial 1978 Safety Report were rewritten.

Upgrading of NPP V-1 units (so-called „small reconstruction“) was performed based on ČSKAE decisions Nos. 5/91 and 213/92. As a result of the above mentioned upgrading, some chapters concerning safety analyses of the NPP V-1 Safety Report issued in 1990 had to be amended. This amendment to the chapter „Safety Analyses“ was done by VÚJE in 1993.

A safety analysis report for gradual upgrading of NPP Bohunice V-1 has been placed in 1993.

Safety Analysis Report after the gradual upgrading

Within the project preparations for the gradual upgrading of NPP V-1, the extent of the amendment to the Safety Report due to the extent of the gradual upgrading was reassessed, resulting in the decision to prepare a new Safety Analysis Report as a whole under the title „NPP V-1 Safety Report after Gradual Upgrading“. In clarifying the structure of the Report, it was decided and approved by ÚJD that base the new Report will follow the structure of the NRC Guideline 1.70, updated based on specific conditions prevailing at NPP V-1, while accounting for the applicable IAEA Guidelines and regulations for safety reviews of WWER units.

The objective was to prepare the NPP V-1 SAR to account for any changes in the technological systems implemented both during the previous operation and during the „gradual upgrading“. In doing this, safety analyses were required to meet all the requirements of the guidelines for the conduction of safety analyses for power plants operating WWER reactors with respect to both the range of initiating events and the approach to the solution and use of programme codes. The structure of the Safety Report is comparable with that of the NPP V-2 Safety Report.

The objectives of the individual chapters remained preserved, although the contents of some parts were adjusted and updated for the conditions of NPP V-1 since the Guideline RG 1.70 has been intended for the drafting of the safety report of new NPPs in the legal environment of the US.

Any principal deviations from the Guidelines RG 1.70 arise from the guidelines developed and issued by IAEA and ÚJD after 1993, thus accounting for the most recent level of knowledge and approaches to analyses, and approaches and taking into account also the specifics of WWER-440 reactor units.