By Yuka Hayashi
TOKYO—Water containing radioactive substances may have leaked into the ocean from the Fukushima Daiichi nuclear plant on Thursday, the plant operator said, the latest example of continued problems at the stricken plant more than three months after the government declared conditions there stabilized.
The leakage was at a pipeline carrying concentrated radioactive water from a desalination device to a storage tank early in the day, plant operator Tokyo Electric Power Co. said in a news release. The leak was contained after 30 minutes when valves were closed.
The company estimates roughly 12 tons of contaminated water may have escaped into the ocean. High levels of cesium 134 and 137 were confirmed at the point of the leak roughly 300 yards from the ocean, but no detectable amounts of radioactive contamination have been found in the sea water.
The company will further investigate the possible spread of contamination and its potential impact in the ocean, including the existence of beta radiation that could contain harmful strontium, company spokesman Yoshikazu Nagai said.
The amount of water reportedly released was tiny compared with the amount Tepco dumped into the ocean during the early weeks of the accident. The Japanese government alarmed neighboring countries in April last year when it approved the discharge of 10,000 tons of low-level radioactive water from the plant as Tepco ran out of space to store the water used to cool reactors.
Thursday’s leak came on the heels of several other problems at the plant.
In late March, Tepco said readings of airborne radiation inside the containment vessel at the No. 2 reactor had surged to a deadly 79 sieverts, the highest level since the crisis began March 11 last year. That came alongside news that the volume of the reactor’s cooling water had declined sharply.
A leakage incident near the desalination facility similar to Thursday’s was also reported March 26.
Such problems have cast doubts about the plant’s stability long after the government declared in late December the reactors had been brought under control.http://online.wsj.com/article/SB10001424052702304072004577325262638144008.html