Authorities look into cause of accidental discharge of potentially contaminated water from nuclear plant

The Wolseong nuclear power plant complex in Gyeongju, North Gyeongsang Province / Korea Times file

The authorities are looking into the cause of an unintentional discharge of 2.3 tons of stored water from spent fuel storage at the Wolseong No. 4 nuclear power plant in southern South Korea, officials said Saturday.

The Nuclear Safety and Security Commission (NSSC) said it received the report on the discharge of the water into the sea from the Korea Hydro & Nuclear Power Co. (KHNP), the operator of the Wolseong plant, at 7:53 a.m.

KHNP discovered a decrease in the water level of the spent fuel storage at 4:34 a.m. and immediately took measures to stop the discharge.

The radiation of the discharged water was estimated at 0.000000555 millisievert (mSv), far below the average radiation dose limit of 1 mSv for an individual for one year.

An NSSC official said the agency suspects there was a problem between the coolant water, used to cool the spent fuel, and the device used to cool this coolant water.

"We have blocked the storage to prevent any further leaks and are investigating the exact cause," the official said. (Yonhap)