The International Atomic Energy Agency (IAEA) has again rotated its team at the Zaporizhia NPP (ZNPP). Since the Agency established a continued presence at the site in September 2022, 20 teams of experts have crossed the frontline of the conflict in Ukraine to reach the plant, Director General Rafael Mariano Grossi said.
On the ground, the IAEA team at ZNPP reported hearing explosions, including close to the plant, on several days over the past week. They confirmed with the plant that one of the mines located next to the ZNPP cooling pond area exploded on 11 June. There was no physical damage or casualties and the cause of the explosion was not shared with the IAEA team.
“This latest explosion, so close to the plant, is of grave concern and is aggravating an already fragile situation,” said Grossi, adding that “nuclear safety and security of the ZNPP cannot be compromised.”
IAEA experts visited one of the electrical sub-stations located in the nearby town of Enerhodar to observe the impact of an alleged shelling which, according to the ZNPP, occurred on 8 June. The alleged shelling resulted in a fire and damage to the substation which serves the Enerhodar city council building where the main communication hub between the ZNPP and Enerhodar is located. The ZNPP confirmed that the damage did not interrupt the communication lines.
The IAEA team also observed testing of one of the safety trains in unit 2 at the plant. Nuclear power reactors, such as those at the ZNPP, each have three separate and independent redundant systems – known as safety trains – comprising their safety systems. The planned test simulated the loss of regular power supply to one of the safety trains, which required the emergency diesel generator of that safety train to activate to supply the power required. The team was informed by the ZNPP that the test was successful, and no issues were identified.
During meetings with the ZNPP over the past week, the IAEA team discussed the number and qualification of staff working in the main control room of the plant. The ZNPP confirmed that, with all six units being in cold shutdown, three authorised personnel would be on duty for each shift in the main control room, with a minimum requirement for two to be present at all times.
As part of its regular walk downs of the plant, the team visited the pumping station of unit 4 where one circulation pump is used to maintain the flow of cooling water between the ZNPP discharge and intake channels. The operation of the circulation pumps is dependent on the overall water level in the ZNPP cooling pond, which continues to drop after the destruction of the Kakhovka dam in June 2023.
The IAEA experts were recently informed that the ZNPP has installed a submersible pump near the isolation gate of the discharge channel of the Zaporizhia Thermal Power Plant, which is capable of pumping 100 m3 of water per hour from the Kakhovka reservoir into the channel, which is then pumped into the ZNPP cooling pond. The 12 sprinkler ponds used to cool the six reactors and safety systems continue to be fed with approximately 250 m3 of water per hour from 11 groundwater wells.
The team also observed the real-time monitoring system of the storage casks, containing used fuel from all six reactors, at the ZNPP dry spent fuel storage facility.
Emergency preparedness and response arrangements are crucial for nuclear safety at any nuclear power plant. The IAEA team engaged in discussions with ZNPP regarding the outcomes of the emergency drill conducted at the plant in May. ZNPP confirmed that the drill successfully achieved its objectives and identified several valuable lessons. An action plan is being implemented to address the areas identified for improvement during the drill.
The Russian Defence Ministry showed footage of the rotation of the IAEA experts. The Ministry said a ceasefire was declared along the entire route of movement of observers from the designated crossing point – the destroyed bridge near the settlement of Kamenskoye, “As part of the mission, four inspectors arrived, their task is to monitor and assess the safety status of the Zaporizhia NPP,” the Ministry report said.