Just a week after Japan’s nuclear regulator declared the leak of radioactive water at the Fukushima Daiichi nuclear plant big enough for a Level 3 incident rating, the regulator’s head is wondering publicly if it really deserved that rating after all.
Based on the International Nuclear and Radiological Event Scale, a Level 3 rating is considered a “serious incident.” For the sake of comparison, the 2005 leak of 83,000 liters of radioactive waste at the Sellafield nuclear reprocessing site in the U.K. was also given a Level 3 rating on the International Atomic Energy Agency’s scale. Both the Fukushima Daiichi and the Chernobyl disasters were assigned the scale’s highest Level 7 rating.
While it might seem like Tokyo Electric Power9501.TO -2.55%, the plant’s operator, would have a precise measurement of the amount of water that had been leaked, the current incident actually started with puddles discovered outside a storage tank of contaminated water. When workers subsequently checked the levels of the 1,000 metric ton water tank, they found only 700 tons. The missing water was presumed to have drained into a surrounding trench.
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“I have not been convinced with the data from Tepco. We need to collect more to make our own judgment,” said Mr. Tanaka.
The supposedly huge water leak is reminiscent of a case this past April, when Tepco announced up to 167 tons of contaminated water leaked from underground storage pools. At that time, Tepco hurriedly calculated the number and announced it to the public. But several weeks later, it revised down the amount sharply to about a few dozens liters after careful double checks.
A Tepco spokeswoman said “it’s true that we calculated 300 tons. We cannot say whether we will or we won’t change it later.”
Read more at Fukushima Watch: Authority Chairman Not Convinced Level 3 Needed
