Key Points

In early July, South Korea's nuclear safety watchdog, along with the oceans and environment ministries, conducted contamination tests for uranium, cesium and five heavy metal variants at 10 river sites near North Korea in connection with the alleged wastewater discharge.

The move came after a recent news report that North Korea may have dumped wastewater from a uranium refining plant in Pyongsan County into the Ryesong River that flows into South Korea, Yonhap news agency reported.

"Test results confirmed there were no abnormalities," Chang Yoon-jeong, deputy spokesperson at the ministry, said at a press briefing.

Uranium concentrations at six of the 10 locations tested near Ganghwa Island and Gimpo ranged from 0.135 to 1.993 parts per billion (ppb) in the latest probe, similar to levels recorded in 2019, which ranged from 0.59 to 1.97 ppb, the unification ministry said. The comparable average uranium concentration in the Han River, which flows across Seoul, was 0.31 ppb in 2019.

Uranium concentrations at the other four sites tested, including the estuary of the Han River and Incheon, were also within normal levels, ranging from 0.087 up to 3.211 ppb, the ministry said, noting that the maximum allowed uranium level in drinking water is 30 ppb.

Chang noted, however, that the latest tests were merely a joint environmental contamination probe by South Korean agencies and do not confirm whether the North released uranium wastewater.

She said the government will continue monthly contamination monitoring at seven major test sites to help alleviate any public concerns.

- IANS