Starting last Saturday, the IAEA team heard around two dozen explosions over three days, followed by several more in the last few days
International Atomic Energy Agency (IAEA) experts based at Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) have reported hearing numerous explosions over the past week, in a possible sign of increased military activity in the region that could also pose a potential threat to nuclear safety and security at the site, Director General Rafael Mariano Grossi said today.
Just over a year after the IAEA established a permanent presence at Europe’s largest nuclear power plant (NPP) to help prevent an accident there during the conflict in Ukraine, the overall situation at the facility remains highly precarious, Director General Grossi said.
Starting last Saturday, the IAEA team heard around two dozen explosions over three days, followed by several more in the last few days. There was no damage to the plant itself.
“The reports I receive from our experts indicate that the explosions occurred some distance away from the Zaporizhzhya Nuclear Power Plant. Nevertheless, I remain deeply concerned about the possible dangers facing the plant at this time of heightened military tension in the region,” Director General Grossi said, again stressing the importance of all parties adhering to the five concrete principles for the protection of the ZNPP.
“Whatever happens in a conflict zone wherever it may be, everybody would stand to lose from a nuclear accident, and I urge that all necessary precautions must be taken to avoid it happening,” he said.
Separately, the ZNPP informed the IAEA team that more drone strikes had taken place in the nearby city of Enerhodar – where many plant staff live with their families – in the morning of 7 September. No casualties were reported. In addition, the IAEA team was informed that the ZNPP had decided to temporarily reduce the number of personnel on the site to minimum levels over the next few days due to concerns of a higher risk of military activities in the area.
At the plant, the IAEA experts observed the continued presence of mines between the perimeter fences, but they did not see any additional ones during their walkdown activities across the site. However, they have still not been granted access to the rooftops of reactor units 1, 2, 5 and 6. The IAEA team has also been requesting a walkdown of all six turbine halls, one after the other, to be able to fully assess, at one time, whether there may be any items present that may be in contravention of the five principles. At present, this request has not been granted.
“To monitor compliance with the five principles, we must be able to have full access,” Director General Grossi said.
Three months after the downstream Kakhovka dam was destroyed – causing the depletion of the huge reservoir that the ZNPP had been relying on to cool its reactors and spent fuel – the plant continues work on expanding access to other sources of water, for example through the drilling of groundwater wells. So far, seven such wells of a planned total of 10-12 have been completed.
In recent days, the IAEA team observed – on two separate occasions – the operation of these wells supplying the sprinkler ponds, which are located next to the six reactors and used for the plant’s cooling functions.
The ZNPP has informed the IAEA team that the seven wells currently operating are accounting for just over half of the approximately 250 cubic metres of water per hour that are required to maintain the cooling water in the sprinkler ponds. This assumes all units remain in a shutdown state. The remaining volume of cooling water is currently pumped from the site’s drainage system. As a result of the new wells, the ZNPP also informed the IAEA that the height of the groundwater had only declined by a very minor level.
The IAEA team reported that the ZNPP is performing maintenance on different components and safety systems at the facility, whose six reactors remain shut down, one in hot shutdown and the others in cold shutdown.
On 4 September, a water leak was detected in a recirculation valve of the essential service water system in reactor unit 5. To repair this valve, the site had to place one safety train of unit 5 and one of unit 6 offline. After the valve was repaired, the safety train of unit 6 was returned to stand-by mode, while that of unit 5 was kept offline for maintenance work. Each reactor at the ZNPP has three separate and independent redundant systems (also called “safety trains”) that together comprise the units’ safety systems, which are normally in stand-by mode ready to activate if needed to maintain the reactor unit’s safety. One safety train alone is capable of maintaining the reactor unit’s safety.
Maintenance activities of the safety systems of unit 4 are also taking place, including of its transformer, heat exchangers and emergency diesel generators. Once they are completed, the site will conduct the final test of the steam generator that was repaired after a water leak was detected in this unit last month.
Over the past week, the IAEA team also conducted other walkdown activities within the site perimeter, including at the main control room, emergency control room and the safety systems rooms of unit 6 and the turbine hall of unit 3 where the team reported that there was no military equipment present at the time of its visit. This morning the IAEA experts visited the turbine hall of reactor unit 1 where they observed a total of fifteen vehicles, but no heavy weapons.
The ZNPP continues to receive off-site power from the last remaining 750 kilovolt (kV) power line and a single 330kV backup power line. The IAEA experts were informed by the ZNPP that the site currently does not have any information on the status of repairs of the damaged off-site power lines as they all pass through the military conflict areas.
Elsewhere in Ukraine, rotations of the IAEA experts have been conducted this week at the Khmelnitsky, Rivne and South Ukraine NPPs and a rotation of the team at the Chornobyl site is scheduled for next week. The IAEA teams at the four sites did not report any nuclear safety or security issues.
Source: Company Press Release