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 September 30, 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 appendix. 

Therefore, we informed Nuclear and Industrial Safety Agency (NISA) and
the government of Fukushima Prefecture of the results above.

We will continue to conduct the same kind of sampling.

* Pit: vertical shaft made of concrete 

Appendix1: Nuclide Analysis Results of Radioactive Materials in Seawater 
           Fukushima Daiichi Nuclear Power Station; the shallow draft quay, 
           Unit 1-4 screen, and the water intake canal of Units 1-4 
                                                              (PDF 15.0KB) 
Appendix2: Radioactivity Density of Seawater (PDF 42.1KB)