Auxiliary water pump was started during manual stop, and the Nuclear Safety Committee (Chairman Kuk-hee Yoo) reported that the auxiliary water pump 2 at about 9:32 a.m. on the 16th was in the process of manually stopping the turbine while the Hanul Unit 1 was lowering its output for planned preventive maintenance. Confirmed that the master has moved. If it is normal, if the output is lowered and the turbine is manually stopped, the auxiliary feed water pump should not start. This matter is a reportable case according to the NSSC regulations. An expert from the Korea Atomic Energy Research Institute will be dispatched to investigate the cause of the maneuver. Yoo Gook-hee, chairman of the National Security Agency, is presiding over a video conference to check safety accident readiness posture. [Photo = Wonanwi] It is known that Hanul Unit 1 is currently in a safe and stopped state. It is reported that additional investigations will be conducted to determine the cause of the auxiliary water pump start-up.