No Tritium Detected in Fukushima Seawater, Says Japan’s Environment Ministry in First

The Yomiuri Shimbun
The Fukushima No. 1 nuclear power plant in Fukushima Prefecture is seen on Thursday.

The Environment Ministry has announced that the concentration of tritium in seawater in the vicinity of the Fukushima No. 1 nuclear power plant is below detectable levels.

The announcement was made after analyzing seawater collected Friday at 11 locations near the plant being decommissioned by Tokyo Electric Power Company Holdings, Inc. Treated water from the nuclear facility that is diluted by seawater has been released into the sea since Thursday.

At each of the locations, the concentration of tritium, a radioactive isotope of hydrogen, was found to be below the detection limit of 7 to 8 becquerels per liter, confirming the absence of anomalies.

This marks the first release of monitoring results by the ministry since the release of the treated water. The seawater analysis was consistent with TEPCO’s previous data.

From Friday morning, the ministry sampled seawater from the 11 locations within about 40 kilometers of the power plant. Concentrations of substances like cesium-137 were also examined at three of the locations, all of which remained below the detection limit.

That same day, TEPCO also released the results of its seawater analysis from 10 locations in the surrounding area. Tritium concentrations have consistently remained below the detection limit thus far.