South Korea Approves Restart of Shin-Kori Unit 1

The Nuclear Safety and Security Commission (NSSC) of South Korea announced on August 21 that it has approved the restart of Shin-Kori Unit 1, located in Ulju County, Ulsan. The unit has been under routine inspection since July 2.

On the same day, the commission approved the unit to reach criticality. Criticality refers to the state in which a sustained nuclear fission chain reaction can be maintained within the reactor core, with a balanced neutron population. Once criticality is achieved, the reactor can gradually resume operation under safely controlled conditions.

The NSSC stated that this routine inspection involved 98 inspection items required before the reactor could reach criticality, of which 86 have been completed, confirming that the unit meets the conditions for safely achieving criticality.

During the inspection, foreign objects were discovered inside the steam generator and subsequently removed, followed by re-inspection of the related heat transfer tubes to confirm their safety. Additionally, the inspection revealed that the fixed anchors at the elbows of the rotating screen piping in the component cooling water system were installed inconsistently with the design drawings, and all related components have been reinstalled.

The NSSC stated that it will continue to verify the operational safety of the unit through subsequent inspection items, including power ascension tests.