The State Nuclear Regulatory Inspectorate of Ukraine (SNRIU) has issued an order to put Zaporizhzhya NPP Unit 5 into cold shutdown mode.
"The order was issued to the operating organisation due to the impossibility of eliminating the identified violations of nuclear and radiation safety requirements, namely: paragraph 4, chapter 1, section 4 of the requirements for emergency cooling systems for nuclear fuel and heat removal to the final absorber," the SNRIU explained on its website.
Among the factors that influenced this decision, the SNRIU named the following:
- Ukrhydroenergo's information of 6 June 2023 on the emptying of the Kakhovka reservoir in a few days as a result of the blow-up of the Kakhovka hydroelectric power station by the Russian occupiers;
- continuing incessant shelling of the Zaporizhzhya NPP industrial site and adjacent territories by the occupiers, which damaged the overhead lines connecting the plant to the Ukrainian power grid;
- termination of data transmission of the ZNPP Automated Radiation Monitoring System (ARMS), which performs the function of early warning, from 17 May 2023;
- degradation of the emergency response system at the ZNPP site and beyond under the temporary occupation.
"Given the loss of the main design source of splash pool feeding, it is necessary to immediately start transferring ZNPP Unit 5 into the cold shutdown mode while the design mode of operation of the necessary cooling systems is still maintained," the order says.
The restriction on the operation of Zaporizhzhya NPP Unit 5 will remain in force until the identified violations are eliminated.
The IAEA mission, which is present at the occupied Ukrainian nuclear power plant, should help ensure compliance with safety requirements and monitor compliance with basic safety principles.
The SNRIU added that the operation of other ZNPP units (Nos. 1, 2, 3, 4, 6) is also limited because they are in the cold shutdown mode.
Last month, Russian propaganda spread false information about the alleged shutdown of all ZNPP units. Energoatom then reported that five power units were in cold shutdown, but Unit 5 was in hot shutdown.
Last September, Zaporizhzhya NPP Unit 6 was disconnected from the grid.