The International Atomic Energy Agency (IAEA) says the impact of the damage to the dam on cooling water supplies to the Zaporizhzhia nuclear power plant is being monitored but alternative sources of water on-site should provide sufficient water for cooling “for some months” and means “our current assessment is that there is no immediate risk to the safety of the plant”.
In an update to the IAEA board of governors on Tuesday morning, Director General Rafael Mariano Grossi said the damage to the Nova Kakhovka dam – which Ukraine says was caused by the Russian shelling, and Russia blames on Ukraine – had led to a “significant reduction in the level of the reservoir used to supply cooling water” to Zaporizhzhia nuclear power plant.
The cooling water system at the plant is used for residual heat removal from the reactors (used or partially used fuel there), residual heat removal from the used fuel ponds and cooling of emergency diesel generators if and when they are running.
“Absence of cooling water in the essential cooling water systems for an extended period of time would cause fuel melt and inoperability of the emergency diesel generators,” Grossi said.
IAEA staff at the plant have been told that at the moment there is a 5cm per hour reduction in the height of the reservoir, “the main line of cooling water is fed from the reservoir and pumped up through channels near the thermal power plant to the site. It is estimated that the water through this route should last for a few days”.
The water level in the reservoir was about 16.4 metres at 08:00 local time – with the IAEA saying that if the level drops below 12.7 metres it can no longer be pumped. The damaged dam itself is about 140km downstream of the nuclear power plant.
