ZNPP's last operating unit is being put into "cold shutdown" mode: what it means
The State Nuclear Regulatory Inspectorate of Ukraine has ordered Energoatom to put Zaporizhzhya NPP Unit 5 into cold shutdown. The operation restriction will be in effect until the identified violations are eliminated.
This was reported by the SNRIU press service. So far, the design mode of operation of the necessary cooling systems has been maintained.
"Given the loss of the main design source of splash pool feeding, it is necessary to immediately start transferring ZNPP Unit 5 to the cold shutdown state, while the design mode of operation of the necessary cooling systems is maintained," the order says.
The order was issued to the operating organisation due to the inability to eliminate the identified violations of nuclear and radiation safety requirements. This mainly concerns malfunctions in the emergency cooling systems for nuclear fuel and heat removal to the final absorber. This decision is made to ensure safety and prevent potential emergencies at the facility.
It is noted that the following factors were taken into account when adopting the order:
- information from Ukrhydroenergo dated June 6, 2023 about the triggering of the Kakhovka reservoir in a few days as a result of the Russian occupiers' blowing up the Kakhovka HPP;
- continued periodic shelling by the occupiers of the industrial site of the Zaporizhzhya NPP and adjacent territories, which damages the overhead lines of communication between the Zaporizhzhya NPP and the Ukrainian power system;
- termination of the transfer of the ZNPP Automated Radiation Monitoring System (ARMS), which performs the function of early warning, from May 17, 2023;
- degradation of the emergency response system at the ZNPP site and beyond under the conditions of Russia's temporary occupation of ZNPP.
Restrictions on the operation of Zaporizhzhya NPP Unit 5 will remain in force until the identified violations are eliminated.
"The presence of a permanent international IAEA mission at Zaporizhzhya NPP will help ensure compliance with safety requirements and monitor compliance with the basic safety principles proclaimed by IAEA Director General Rafael Grossi," the SNRIU said.
As reported, the operation of other ZNPP power units - No. 1, 2, 3, 4, 6 - is also limited to the "cold shutdown" state, in accordance with SNRIU orders of August 18, 2022 and February 10, 2023.
As OBOZREVATEL previously reported, the occupied Kinburn Spit was cut off from the mainland due to significant flooding. It happened as a result of the dam at the Kakhovka hydroelectric power station being blown up by Russian forces.