Builders have begun to reinforce the lower part of the foundation for the reactor building for unit 8 at Russia’s Leningrad NPP. To lay the foundation of unit 8, builders will need almost 2,000 tonnes of steel reinforcement and more than 5,000 cubic metres of special durable concrete.
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. They are scheduled to be put into commercial operation in 2030 and 2032.
“Today we are laying the foundations for the safety of the most important facility of the power unit. We need to create a foundation slab that will evenly distribute the load on the ground from the 70-metre reactor building as well as the reactor, steam generators, circulation pumps and other large equipment operating inside it to ensure their reliable operation,” said Evgeniy Milushkin, Deputy Director for Capital Construction and Head of the Capital Construction Department of Leningrad-II. “Simultaneously with the reinforcement, we will install sensors to monitor the integrity and tightness of the reactor building shell, and we will continue to install a closed, controlled grounding loop. In November-December, we will begin reinforcing the foundations for other objects of the nuclear island.”
According to the schedule, work on reinforcing the foundation slab of the reactor building will be completed in the second quarter of 2025. After this, the builders will begin concreting the foundation, erecting protective shells and floors of the building, as well as installing equipment. In total, construction and installation work at unit 8 will last for seven years. After this, pre-launch adjustment work will be carried out, physical and power start-ups of the nuclear reactor and pilot operation of the unit will take place.
Meanwhile, unit 5 has restarted operation after a planned maintenance and refuelling outage. Employees of specialised industry organisation Lenatomenergoremont, and representatives of the repair services of the main units of the Leningrad NPP conducted an audit and maintenance of reactor and turbine equipment, safety systems, diesel generator sets, lifting mechanisms, tested the sealed shell of the reactor building to confirm its integrity and strength. “We have completed all the work stipulated by the repair programme,” said Alexander Belyaev, chief engineer of the Leningrad-II. “Also, as part of the repair, the pumping units for the first circuit of the reactor unit and the data transfer system were modernised.”
