An earthquake with a magnitude of 3.1 struck at 6:43 a.m. on the 23rd, 21 kilometers northwest of Haenam County, South Jeolla Province. The Nuclear Safety and Security Commission said it inspected the safety of all domestic reactor facilities in connection with the quake and confirmed there were no abnormalities.
The reactor facility closest to the epicenter was identified as the Hanbit Nuclear Power Plant, about 83.2 kilometers away. The measured ground acceleration there was 0.0032g, far below Hanbit's seismic design threshold of 0.2g. The Nuclear Safety and Security Commission said this level of vibration is not enough to affect facility operations.
The Nuclear Safety and Security Commission's Hanbit nuclear plant regional office conducted an emergency safety inspection of the Hanbit site immediately after the quake. The inspection also found no particular signs of abnormality.
Seismic readings at other nuclear facilities were also all minimal. Kori recorded 0.0016g, Saeul 0.0004g, Wolsong 0.0002g, and Hanul 0.0008g, while the research reactor Hanaro showed the lowest value at 0.0001g.