The Fukushima Daiichi Nuclear Power Plants continue to drain away water containing cesium 137 into the ocean

Until June 2011 since the reactor meltdown of the Fukushima Daiichi Nuclear Power Plants occurred through which about 0.95 PBq of Cs 137 was estimated to release in the environment. The present author investigated a balance sheet between incomings and outgoings of radioactive cesium in the harbor of Nuclear Power Plants by considering the structure of the harbor and exchange rate of the sea water as well as the results of the radioactivity measurements outside the harbor to conclude that mean effluent quantity per day for the period between June and August in 2011 is 93.2 GBq/day. The possible influences of oceanic contamination are discussed. (S. Ohno)