The second tier of the inner containment (VZO – Vnutrennei Zatsitnoi Obolochki) has been installed at Leningrad NPP unit 7 (also known as Leningrad-II unit 3). The operation was witnessed by Rosatom Director General Alexey Likhachev and the Governor of the Leningrad Region, Alexander Drozdenko.
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 the RBMK-1000 reactors at units 1&2, which were decommissioned in 2018 and 2020. New VVER-1200 units (7&8), now under construction, will replace units 3&4.
The VZO long with the outer containment (NZO – Naruzhnoi Zatsitnoi Obolochki) are a distinctive safety feature of VVER-1200 reactors. The double shell ensures the tightness of the building under all operating modes and protection from external extreme influences.
Likhachev noted the importance of the facility for the region. “The North-West of our country is traditionally energy-intensive; industry and port infrastructure are actively developing here. Our two nuclear power plants operating in the region – Leningrad and Kola have a total capacity of more than 6,000 MWe. Together they provide more than 35% of power generation. Both stations have been operating for more than 50 years, and each of them is now getting a replacement capacity that can operate for at least another 60 years.”
Alexander Drozdenko noted: “We are convinced that the construction of replacement capacities at the Leningrad NPP is proceeding at a good pace. The quality, volume and timing of construction and installation work are under the strict control of the customer, the general contractor and government inspection services. There is confidence that the new power units will be put into operation in accordance with the schedule and are guaranteed to provide electricity to millions of our households and hundreds of industries, as well as medical, cultural and sports institutions. They will support significant investment projects and will be the key to improving the standard of living in our region.”
Current work is focused on nuclear islands of units 7&8. About 1,500 highly qualified specialists from general contractor TITAN-2 are employed at the site. Nuclear officials monitor the progress of construction and installation work. The installation of the VZO weighing 260 tonnes was carried out with precision. The builders have a large amount of work ahead on the internal and external containment including reinforcement and concreting, installation of a prestressing system, etc. The double containment should be completed in 2028.
