INES Not Applicable
At 23:25 (Japan time) on 19 February, 2014, TEPCO found that water was leaking from the upper part of Tank C-1 in H-6 Tank Area, which has stored the water that was condensed by RO (reverse osmosis desalination facility) after the treatment by SARRY (cesium removal facility), to the dike surrounding H-6 Tank Area and to the outside of the dike through the rainwater drainpipe running from the upper part of Tank C-1 to the ground surface beyond the dike.
At 05:40 (Japan time) on 20 February, 2014, TEPCO succeeded in stopping the water leakage by means of closing the valves installed between Tank C-1 and RO and tranferring some amount of the water stored fully in Tank C-1 to other tanks in H-6 Tank Area. The amount of water, which leaked to the outside of dike, was estimated to be approximately 100 m3.
The concentration of radioactive materials in the water leaked to the outside of the dike is as follows:
Cs-134: 4.2 kBq/L
Cs-137: 7.3 kBq/L
Co-60: 2.9 kBq/L
Sb-125: 41 kBq/L
Total Beta: 240 MBq/L
There has been no contamination of the ocean that raises any concern about influence to heaith and the environment.
Event date: Thu, 20-02-2014