At around 10:28 am on January 10, 2012, at the concentrated water tank of water desalinations (Reverse Osmosis Membrane) at Fukushima Daiichi Nuclear Power Station, our employee found water dripping from the packing at the base of the concentrated water storage tank at the rate of approximately a drop per second and also found accumulated water on the concrete where the tank is mounted.
The amount of leakage is estimated to be approximately 10 liters. We re-torqued the bolt at the joint of the tank, and confirmed that the water dripping had stopped at around 12:35 pm on the same day.
In addition, in order to prevent the water leakage from spreading, we stacked sand bags around the accumulated water.

Regarding this matter, we received a directive^* titled "Action in the event of water or radioactive material leakage from the storage tank of water desalination at Fukushima Daiichi Nuclear Power Station" from the Nuclear and Industrial Safety Agency (NISA) on January 10, 2012.

At around 12:30 pm on February 3, we found ooze at the tank joint of the concentrated storage tank of Water Desalinations (Reverse Osmosis Membrane). We retightened the joint bolts afterwards, and at around 2:44 pm on the same day, we confirmed that the ooze from the joint had been stopped.
Although there was not accumulated water on the concrete on which the tank is mounted and no leakage to the sea was found, we stacked sand bags around the accumulated water as a precautionary measure.
Regarding this matter, we received the directive* titled "Action in the event of water or radioactive material leakage from the storage tank of water desalination at Fukushima Daiichi Nuclear Power Station (additional direction)" from NISA on February 3.

After that, out of the directive received on February 3, we reported on the results of investigation and countermeasure on the outdoor storage tank to NISA on February 8.

(previously announced on January 10, February 4 and 8, 2012)

Today, we have reported on the summary of our correspondences to NISA regarding the directives received on January 11 and February 3, 2012, from NISA.

END

Attachment
・Report on the "Action in the event of water or radioactive material leakage from the storage tank of water desalination at Fukushima Daiichi Nuclear Power Station" (PDF 1.49MB)

* The attached file titled "Report on the "Action in the event of water or radioactive material leakage from the storage tank of water desalination at Fukushima Daiichi Nuclear Power Station"" is only available in Japanese.
We apologize for any inconvenience this may cause.

We have provided a Japanese press release version of the instruction document received from NISA.  However, at this time we have reserved the right to not provide an English version due to potential misunderstandings that may arise from an inaccurate rendering of the original Japanese text. 
We may provide the English translation that NISA releases in our press releases. However, in principle we would advise you to visit the NISA website for timely and accurate information.