The construction of two VVER-1200 reactor units of the Leningrad NPP is proceeding at a good pace. By completing the work planned for 2025, builders and installers are ahead of schedule for many facilities.
Currently Leningrad NPP has four units in operation – units 3&4 with Soviet RBMK-1000 reactors, as well units 5&6 with new VVER-1200 units (also known as Leningrad-II 1&2). Units 5&6 replaced units 1&2 with RBMK-1000 reactors, which were decommissioned in 2018 and 2020. New VVER-1200 units (7&8) will replace units 3&4.
“The results of last year and this year convincingly prove that we are coping with the tasks set,” said Vladimir Pereguda, Director of the Leningrad NPP. “In 2024, the builders concreted the lower part of the foundation for the reactor building unit 3 in 103 days. This is 12 days ahead of the deadline stipulated by the local schedule. This year we have achieved a record 80 days. At the same time, the quality of construction and installation work remains at the highest level as confirmed by inspections.”
To make the base for the unit 8 reactor building, the builders used steel reinforcement with a diameter of 16-40 mm and special, heavy, high strength concrete. In total, they needed almost 2,000 tonnes of rebar and more than 4,000 cubic metres of concrete mix to build a structure with an area of 2,100 square metres and a height of two metres.
Currently, builders allowing the concrete to gain strength. After confirming the quality of the lower part of the foundation, they will begin reinforcing and concreting its upper part, “increasing” its thickness by almost one and a half metres. Builders and installers will also begin to erect walls and ceilings, lay pipelines, install hermetic penetrators and install equipment. The “melt trap”, one of the localising passive safety systems of the power unit, will be the first to be installed in its regular place. This key operation is scheduled for 2026. The reactor vessel will be installed in 2029.
Currently, construction and installation work is underway at the site on 16 facilities for unit 3 and at nine facilities of unit 4. The main efforts of the builders are focused on the nuclear islands. Work at these facilities is proceeding efficiently.
“The foundation of the reactor building for unit 4 was completed ahead of schedule and with high quality, said Konstantin Khudyakov, Director of the Leningrad NPP Facilities Programme at general contractor TITAN-2. “This is a natural result of the hard work of our large team. And this success is not an isolated one. In May, we also completed the installation of the foundation plate of the security building ahead of schedule at unit 4, and today we are well moving forward on the foundation of the management building. By the end of the year, we plan to prepare and deliver four more foundations for the nuclear island. At unit 3, we are preparing for the large-scale assembly and installation of the first tier of the reactor building’s inner containment and for the installation of a melt trap.
