Support in the stress tests exercise

Background

Considering the accident at the Fukushima nuclear power plant (NPP) in Japan, the European Council of March 24th and 25th 2011 declared that "the safety of all EU nuclear plants should be reviewed, on the basis of a comprehensive and trans-parent risk assessment ("stress tests") and subsequently opened this European risk and safety assessment for voluntary participation of neighbouring countries”. The "stress test" were defined by the European Nuclear Safety Regulators Group (ENSREG) as targeted reassessments of the safety margins of NPPs in response to external hazards like earthquakes, floods and extreme weather conditions, and in view of a loss of safety functions potentially leading to nuclear fuel damage and requiring severe accident management. This reassessment has been performed in the form of a self-assessment by NPP operators and documented in Self-Assessment Stress Test (SAST) reports. In a second stage, the national nuclear regulators reviewed the operator’s self-assessment reports and subsequently prepared the regulator’s summary National Stress Test Report. Finally, the National Stress Test Reports were subjected to an international peer review. After finalisation of the National Stress Test Re-ports, National Action Plans (NAcP) were prepared by the national nuclear regulators. 

Within the framework of the implementation of Annex III of the Joint Comprehensive Plan of Action (JCPoA) in order to ensure the exclusively peaceful nature of Iran's nuclear programme, the stress test project IRN3.01/16 was launched. The EC has adopted the so-called '2+2' approach for INSC project IRN3.01/16 which comprises 2 lots. Lot 1 has as an overall objective to enhance the capacity and effectiveness of the Iranian Nuclear Regulatory Authority (INRA) by supporting the design of a multi-functional nuclear safety centre for sharing experience and promoting best international practice, by sup-porting improvements in the Iranian regulations on nuclear and radiation safety, by strengthening its safety assessment capabilities for deterministic and probabilistic safety assessment, by supporting the implementation of a post-Fukushima nuclear safety stress test for the nuclear power plant (NPP-1), and finally, by providing training and tutoring. Lot 2 was aimed to support the nuclear power plant operator (NPPD) in the post-Fukushima nuclear safety stress test self-assessment for NPP-1.

The Project (Lot-2) was focused on the Bushehr NPP-1 SAST report development. The German contractor Siemens had begun the construction of two 1,200-1,300 megawatt electric (MWe) pressurized water nuclear reactors near Bushehr as early as in 1974. The unit-1 was 85 percent complete, and the unit-2 was approximately half complete prior to the 1979 Iranian Revolution and was due to be completed in 1981. After 1979, the construction of both reactors was abandoned. During the Iran-Iraq War, Iraqi air strikes partially damaged both reactors. In January 1995 Russia and Iran had signed a contract under which Russia has provided one VVER-1000 reactor at the Bushehr site. The Russian reactor was installed in the original structures designed for the German unit-1. The reactor started up on 8 May 2011, was connected to the grid early September 2011, and started commercial operation in September 2013 when the responsibility of plant operation was handed over to the Iranian party.

The Bushehr NPP-1 plant is owned by the nuclear power production company of Iran (NPPD) that is the licensee as well. Plant operation was delegated to the Nuclear Power Plant Operation Company, a subsidiary of NPPD, which was established in 2004. NPPD is a state owned company and observe the overall policies of the Atomic Energy Organization of Iran (AEOI) established by the  Atomic Energy Organization of Iran Act of 1974.

Objectives

The overall objectives of the project were to: 

• assess the compliance of the existing post-Fukushima nuclear safety SAST report of the NPP with INRA detailed requirements,
• prepare a stress test self-assessment methodology based on a gap analysis of the above mentioned report,
• support NPP (NPPD) operator in the SAST report elaboration consistent with INRA detailed requirements and its justification in front of INRA,
• assist to NPPD in development of a strategy for addressing stress tests recommendations, taking into account also the recommendations of the planned OSART mission,
• help NPPD in the nuclear safety capacity building with the use of the EU knowledge base transfer.

The expected results of the project have not been limited to the stress tests report itself and a set of recommendations, but also to an extensive information exchange and knowledge transfer in order to enlighten the approach to the post-Fukushima event phenomena adopted in various European and neighbour countries with NPPs showing similarities to the NPP technology.