At around 9:30 am on April 2nd, 2011, we detected water containing 
radiation dose over 1,000 mSv/h in the pit* where power supply cables are 
stored near the intake channel of Unit 2. Furthermore, there was a crack 
of about 20 cm length on the concrete lateral of the pit, from where the 
water in the pit was flowing out to the ocean. At around 12:20 pm on April 
2nd, we reaffirmed the event at the scene.
We have implemented sampling of the water in the pit of Unit 2, together 
with the seawater in front of the bar screen near the pit of Unit 2. These 
samples were sent to Fukushima Daini Nuclear Power Station for analyses.

At around 5:38 am on April 6th, we have observed stoppage of spilling of 
water to the ocean from the crack on the concrete lateral of the pit. 

Since April 5th we have been conducting sampling surveys of the water in 
the pit of Unit 2 and the seawater in front of the bar screen near the pit. 
Regarding the survey results of the detection of three nuclides (iodine 
131, cesium 134, cesium 137), we report those as definite results, and for 
the other nuclides, we will re-evaluate them.

On April 12th, due to the installation of silt fences, we changed the 
sampling points from the front of the bar screen of Unit 4 to the north 
and the south of the inside of the water intake canal of Units 1 to 4. 
Since April 17th, we have been conducting an additional sampling survey 
outside the silt fence in front of the bar screen of Unit 2, in order to 
assess the effect of the installation of the silt fence.

On May 11th, 2011, responding to out-flow leakage of contaminated water 
from the intake canal of Unit 3, from May 12th, we additionally conducted 
the sampling of the seawater inside and outside of the silt fence in front 
of the bar screen near the pit of Unit 1, 3 and 4. 
                                                    (Previously announced)

On May 19th, 2011, we conducted the sampling of the seawater near the 
intake canal of Unit 1 to 4 of Fukushima Daiichi Nuclear Power Station and 
analyzed them. As a result, some radioactive materials were detected as 
described in the exhibit. Accordingly, we have reported the result of the 
analysis to NISA and the government of Fukushima Prefecture.

We will continue to conduct the same kind of sampling.

* pit: a vertical shaft made of concrete 

Appendix1:The Results of Nuclide Analyses of Radioactive Materials in the 
          Seawater Fukushima Daiichi Nuclear Power Station the shallow draft quay, 
          Unit 1-4 screen, and the water intake canal of Units 1-4(PDF 18.4KB) 
Appendix2:Radioactivity Density of Seawater (PDF 61.1KB)