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Press Release (Jul 13,2011)
The results of nuclide analyses of radioactive materials in seawater taken in areas near intake canal of Fukushima Daiichi Nuclear Power Station (for the data collected on July 12)
At around 9:30 am on April 2, 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 2, 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 6, we observed stoppage of spilling of water to 
the ocean from the crack on the concrete lateral of the pit. 

Since April 5 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 12, 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 17, 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 11, 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 July 12, 2011, we conducted sampling of the seawater near the intake 
canal of Units 1 to 4 of Fukushima Daiichi Nuclear Power Station and 
analyzed the samples. As a result, some radioactive materials were 
detected as described in the exhibit. Accordingly, today, we have reported 
the result of the analyses to Nuclear and Industrial Safety Agency and the 
government of Fukushima Prefecture.

We initiated closure works at southern part of unit1-4 intake channel to 
prevent high density contaminated water leakage and diffusion yesterday.
We have reported the result of the analyses at additional sampling points 
which were increased to observe the affect of this construction work, too.

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 18.9KB) 
Appendix2: Radioactivity Density of Seawater (PDF 53.5KB) 
Appendix3: Additional sampling point of seawater in the harbor of 
           Fukushima Daiichi Nuclear Power Plant(PDF 10.5KB) 
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