At the Akkuyu NPP under construction in Türkiye, Russian engineers used diamond cutters underwater at a depth of 14 metres, to dismantle 1,920 cubic metres of structures. The work was carried out with the participation of industrial divers in conditions of zero visibility and parallel dredging.
To protect the facility from the Mediterranean Sea, a temporary diaphragm was installed on the site of the future NPP. It comprised a reinforced concrete wall 1-1.4 metres thick and 30 metres high. Some 14 metres of this are below the seabed and 14 metres are under water with only two metres above the water level.
To ensure the intake of seawater, the main source of technical water supply and equipment cooling, the project provided for the dismantling of the diaphragm in front of each of the four pumping stations with a phased transition from one station to another. Each removable part of the diaphragm has a length of about 120 metres. The process had to be performed directly in the marine environment, cutting each removable part of the diaphragm underwater into 90 blocks.
The task was complicated not only by the depth, but also by the need for high-precision work in low visibility. Dismantling was carried out simultaneously with dredging. The situation was also aggravated by extreme weather conditions. Work was carried out on the open coast, where frequent wind gusts and high air temperatures significantly complicated the process. In such circumstances, even a minor mistake could lead to equipment failure, the repair or replacement of which would inevitably disrupt the project delivery schedule. The technical solution was developed by Russian engineers at Reforma, using diamond cutting in seawater.
“The project required maximum precision and full commitment from the entire team,” according to the Reforma press service. “We are proud that 50 Russian specialists were able to realise the most difficult task: to perform 1,850 square metres of diamond cutting under water at a depth of 14 metres, in conditions of zero visibility and at air temperatures up to 50°C. The work was carried out on a site with a width of only 1.5 metres (the distance between the pumping station and the dismantled diaphragm fragment) using equipment weighing up to 950 kg.”
Work started in October 2023 with the signing of a contract for the dismantling of the front walls. The preparatory phase began in December and was completed in January 2024. The dismantling of the first of the four diaphragm fragments was completed in March 2025. Currently, the specialists of the group of companies are carrying out preparatory work for the next stage of work – the dismantling of the second part of the temporary structure. The facility uses diamond cutting manufactured in Liechtenstein by UK-based Hilti.
Akkuyu NPP will eventually host four Russian-designed VVER-1200 reactors. The pouring of first concrete for unit 1 took place in April 2018, for unit 2 in June 2020, for unit 3 in March 2021, and for unit 4 in July 2022. Rosatom is constructing the reactors according to a build-own-operate model. Unit 1 is expected to begin operation in 2025. In July 2024 Akkuyu NPP reported that some 70% of the equipment and systems installed at unit 1 had already undergone commissioning.
