Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) is continuing to pump cooling water from the Kakhovka reservoir even though the water level has reached the point at which it was previously estimated that the pumps could no longer operate, Director General Rafael Mariano Grossi of the International Atomic Energy Agency (IAEA) said today.
The reservoir’s water level has now dropped by around 4.1 metres since the downstream dam was breached early on Tuesday and reached about 12.7 metres at 6pm local time today, the level at which it was earlier estimated that the ZNPP could no longer access this body of water for cooling the plant’s six reactors and spent fuel, after which the plant would use alternative water sources.
The hourly loss rate remains in the range of between 4 to 7 centimetres per hour, Director General Grossi said, citing data from the IAEA team at the ZNPP.
The IAEA experts were informed today that the ZNPP had assessed following a review that it should be able to pump water from the reservoir also after its level falls below 12.7 metres. So far, the results indicate that the pumps can likely still be operated even if the level drops to around 11 metres or possibly lower.
As the ZNPP receives water from the reservoir via the cooling system of the nearby Zaporizhzhya Thermal Power Plant (ZTPP), the review included interviews with retired ZTPP staff who have experience and expertise of the design of this facility’s cooling systems from the time that the ZTPP was built in the 1970s, prior to the construction of ZNPP in the 1980s.
“In these difficult and challenging circumstances, this is providing some more time before possibly switching to alternative water supplies including the large cooling pond next to the plant as well as its smaller sprinkler cooling ponds, the adjacent channels, and onsite wells, which can provide required cooling water for the Zaporizhzhya Nuclear Power Plant for several months,” Director General Grossi said. “Nevertheless, the general nuclear safety and security situation remains very precarious and potentially dangerous.”
The Director General – who will travel to the ZNPP next week – stressed that the extent of the dam’s damage remained unknown, and it is also not clear when and at what level the reservoir will stabilize.
To better assess the situation, the IAEA experts have requested access to the location where the reservoir’s water level is measured and also to the ZTPP discharge channel adjoining the ZNPP.
“It is essential that the ISAMZ team can independently verify the status of the systems that provide cooling water to ZNPP,” Director General Grossi said.