The milestone event of the year has happened at the work-in-progress power unit No. 2 of the VVER-1200 of the Leningrad NPP-2. Correctly, the constructing of the inner containment is completed, the last tier upward to 67 meters is concreted. Now builders will be able to proceed to the constructing of the uppermost part of the dome, which is the buttress upward to 68,5 meters.

The inner containment is the localization safety system of the nuclear power plant. This is a construction made of prestressed concrete and includes a cylindrical part and a hemispherical dome. For the inner containment it took about 11000 cubic meters of concrete and 3000 tons of reinforcement. The thickness of the reinforced monolithic concrete of the inner containment is 1200 mm, which corresponds to the project requirements.

“The constructing of the inner containment is a long complex process. In the course of that, a large amount of physical, technical and labor resources was involved, - Pavel Ivanov, Lead Engineer of the Construction Supervision Services Department of the Capital Projects Division of the LNPP-2 said. - In parallel with concreting, the containment pre-tensioning system was set up. It was critically important for us to complete the constructing of the inner containment on schedule, so that these works could be completed. Now we are starting the next major stage - the vertical and horizontal ropes tension of the containment pre-tensioning system of the reactor dome.

The constructing of the VVER-1200 of the Leningrad NPP provides for a double containment of the reactor building – inner and outer. In case of emergency, the first will prevent radioactive waste release, and the second will be acting as physical protection against natural and man-made impacts, including earthquakes and hurricanes.