The Leningrad NPP-2: the construction of the 2nd power block’s reactor building dome has reached its halfway mark

The construction of the containment dome for the 2nd VVER-1200 power block’s reactor building is still in progress at the Leningrad NPP-2 site. As of today, the construction team has completed over 50% of the activities on the dome reinforcement and concreting. Their main focus is ensuring the quality of the materials used and the works carried out.

‘The reactor building is the most important facility from the nuclear safety standpoint. It has to tolerate extreme man-caused and natural loads. We use reinforcement and concrete that have almost unprecedented quality parameters and can cater for high reliability and durability of the whole structure’, Kirill Mazurin, the deputy chief engineer of construction and installation works at the Leningrad NPP-2 capital construction department, said.

He also explained that both external and internal reactor building containments are stipulated in the Leningrad NPP new power blocks’ construction projects. Double containment is one of the nuclear power plant’s confining safety systems. When the NPP is operational, it will prevent radioactivity from reaching the environment and will act as physical protection against external actions such as an earthquake, a hurricane, a plane falling down on it, an air blast, etc.

The construction of the internal containment for the 2nd VVER-1200 power block of the Leningrad NPP was completed in March. The external layer is due to be finalized at the end of 2019. Following that, the team will carry out another important pre-commissioning activity: there will be a durability and density test for the containment using overload pressure to verify its quality.


Compared to the traditional VVER-1000 power blocks, the project for the 3+ generation Leningrad NPP power block has a number of advantages that considerably increase its economic parameters and safety standards. The capacity of the nuclear facility has been increased by 20%, from 1000 to 1200 megawatt; the designed life span of the core equipment has doubled and is now 60 years. In addition to that, this power block complies with the top international standards with regard to nuclear security. The Leningrad NPP-2 project serves as a reference for several international projects by the Rosatom State Corporation, such as the Belarusian NPP, the Paksh-2 NPP, the El Dabaa NPP, the Hanhikivi-1 NPP, etc.

The Leningrad NPP is the country’s first plant with RBMK-1000 reactors (uranium-graphite circuit-type reactor running on thermal neutrons). The decision that marked its construction was taken in September 1966 by a resolution of the Central Committee of the Communist Party of the USSR and the Council of Ministers No. 800-252. According to that document, the Leningrad NPP was supposed to become a core in a network of nuclear power plants with RBMK-1000 reactors that were supposed to produce a substantial share of electric power. The construction of the Leningrad NPP was going well, and by 1973 the first power block was fully erected. On December 23, 1973, following stable 72-hours’ operation at the capacity of 150 megawatt, the State Commission signed the acceptance certificate stating that the first power block of the Leningrad nuclear power plant is commissioned for pilot production. 

Back to the list