Work has started at the construction site of Leningrad II NPP laying the foundation for the turbine building of unit 3 – also known as Leningrad 7. 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), now under construction, will replace units 3&4.
General contractor TITAN-2 has started to install reservoir drainage at the unit 7 site. Workers will have to make a three-layer building structure from concrete and sand mixture in a pit with an area of about 8,000 square metres, creating a filter layer between it and the future foundation of the turbine building.
“Reservoir drainage is necessary to effectively protect the soil under the foundation of the turbine building from leaching and subsidence,” said Evgeny Milushkin, Deputy Director for Capital Construction and Head of the Leningrad II Capital Construction Department. “By creating a high-quality drainage system, we will ensure the integrity and durability of all building structures that will be built on the foundation in the next stages, and the reliability of the technological systems located there.”
Work on the installation of reservoir drainage will be carried out throughout the autumn. Builders will then carry out concrete preparation and waterproofing for the future base of the facility and create monolithic reinforced concrete tunnels under the foundation slab. Subsequently, they will house pipelines of various systems and cable products for power supply of equipment. Work on reinforcing the foundation of the turbine building will start this year. Builders plan to begin pouring the first concrete at the site in early 2026.
In addition to the turbine building, similar construction work will be carried out at other facilities on the turbine island – the water treatment building, the heating building and the normal operation power supply building.
