Project N0 AR/TS/01:Assit.to the Armenia

The overall objective of this project is to support the implementation of a western technical evaluation process in Armenia, through the assistance of Western technical support organisations to the Armenian Nuclear Regulatory Authority (ANRA).

This assistance consists in transfer of know-how, recommendations and technical support for the evaluation of the upgrading modifications of Medzamor Unit 2, both already implemented and on-going, in the framework of the Armenian decision to re-start the plant after the shutdown following the earthquake in 1988.

The specific objectives are:

• Task a: Transfer of experience concerning a similar upgrading programme of Kozloduy units 1-2 (Bulgaria)

The corresponding evaluation reports will be sent to ANRA and workshops will be organized about the raised technical issues (systems analysis including electrical supply and Instrumentation and Control, internal hazards, vessel and components under pressure including leak before break, operational safety including radiation protection, commissioning tests)

• Task b: Evaluation of the Medzamor Unit 2 upgrading programme after identification of the differences with the Kozloduy upgrading programme.

The evaluation will address the technical issues mentioned in Task a and will deal with the non condensable gases produced in the primary circuit during normal operation as well as with the related remedial measures.

• Task c: Evaluation of specific technical issues, on the demand of ANRA.

Those issues are related to the plant operation with high grid instability and to the emergency plans of the plant and of the Armenian authorities.

Task a: the evaluation reports of the Kozloduy upgrading programme were transmitted to ANRA in February 1997 and discussed during technical meetings in May and June 1997.

Task b: an evaluation of the upgrading programme and of some operational safety problems was carried out. This evaluation addressed the systems analyses, the electrical supply, the Instrumentation and Control, the components integrity, the internal and external hazards, the accident analyses, the operational procedures and the radiation protection. The evaluation report contained recommendations classified as follows:

1. For the most probable events, the recommendations aimed to improve the affected systems in normal operation as well as the safety systems used during these events in order to mitigate the consequence of the events.
2. For the less probable events, the recommendations aimed to reduce the frequency of occurrence by developing preventive measures and accident procedures.
3. For some of the beyond-design-basis accidents, the recommendations aimed to develop a strategy in order to reduce their consequences, using realistic assumptions.

The issue of non-condensable gases in the primary circuit was not specifically addressed in this report.

Task c: a report was issued about the investigation of the Armenian grid instabilities and their influence of the Medzamor plant safety. This report included recommendations concerning the plant and the grid.

Concerning the emergency plans, an Armenian delegation including government representatives, ANRA staff and licensee staff was given presentations about the French organisation and attended an emergency drill in the Saint-Alban nuclear power plant, France, in January 1998.

Task d: This task was added to the initial content of the project. It consisted of the review of the technical specifications of equipment to be installed in Medzamor Unit 2, namely the pressurizer safety valves, the steam generator safety valves, the reactor coolant sampling and analysis system and the chemical analysis of samples. This task is continued in the project AR/TS/02.