The International Atomic Energy Agency (IAEA) has received further details about the dam constructed to secure cooling water for the systems needed to maintain the reactor units at Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) in cold shutdown.
The IAEA team based at the ZNPP received updates on Tuesday regarding the location of the newly built dam and its purpose, which is to isolate one of the ZNPP’s channels from the plant’s cooling pond. The channel in question supplies service water for cooling several plant systems, such as the main unit transformers, required to safely maintain the ZNPP’s six reactors in cold shutdown, which they have remained in since April 2024.
The ZNPP confirmed that the dam will help maintain the water level in the channel at about 14 metres, which is 2 metres above the threshold at which the service water pumps would no longer be able to operate. In addition, the ZNPP continues to use groundwater wells on site to provide cooling water for its safety systems to cool the reactor cores and spent fuel pools.
The IAEA team based at the ZNPP site – Europe’s largest nuclear power plant (NPP) - continues to request access to the newly constructed dam but have not yet been permitted due to security concerns.
“Our access to this dam is essential to assess the cooling water situation which is crucial given the fragile nuclear safety situation at the ZNPP,” said Director General Grossi.
The cooling water situation is compounded by the fact that the ZNPP remains reliant on one single off-site power line to receive the external electricity it needs to cool its six reactors and their spent fuel, almost four months after it lost the connection to its last 330 kV back-up power line.
The IAEA team continues to follow-up on maintenance work on the safety systems and the site’s electrical systems and equipment, including the backup power transformers. On 25 August, the team performed a walkdown of the turbine hall of a reactor unit but could not gain access to the western part of the building.
The IAEA staff at the ZNPP reported hearing military activities on most days over the past week.
Separately, IAEA teams deployed at Ukraine’s operating NPPs – Khmelnytskyy, Rivne and South Ukraine – are monitoring progress of the shutdown activities. The teams confirmed that one unit was returned to operation earlier this week whilst another was shut down for maintenance. Currently seven reactor units are operating, out of nine in total.
IAEA teams reported hearing air raid alarms most days over the past week at the South Ukraine NPP and the Chornobyl site.
The teams at the Chornobyl site and the Rivne and South Ukraine NPPs have all rotated successfully in recent days.?
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