On March 21st, 2011, we conducted sampling, as a part of monitoring of 
surrounding environments, and detected radioactive materials in the 
seawater around the water discharge canal (of the south side) of Fukushima 
Daiichi Nuclear Power Station, which was damaged by the Tohoku - Pacific 
Ocean Earthquake. Therefore, we informed Nuclear and Industrial Safety 
Agency (NISA) and the government of Fukushima Prefecture of the results.  
Since March 22nd, we have conducted seawater sampling surveys at four 
points off the shore of Fukushima Daiichi Nuclear Power Station (twice a 
day at two points out of such four points since March 26th).  

Since April 17th, we have also conducted sampling surveys at four points 
(2 points are added since April 26, another 3 points from April 30th, total 
of 9 points) of 3 km off the shore of Fukushima Daiichi Nuclear Power 
Station, two points of 8 km off the shore of the Power Station and 6 points 
of 15 km off the shore of the Power Station and informed them of evaluation 
results (Regarding 6 points in 9 points of 3km off the shore, from May 9th, 
we conduct sampling at the lower layer added to upper layer. We conduct 
sampling for those 6 points twice a week).

The data of three detected nuclides (Iodine-131, Cesium-134 and Cesium-137) 
will be reported as fixed data. Other nuclide figures are to be 
re-evaluated based on the improved measures for recurrence prevention which 
have been prepared in accordance to a warning from NISA on April 1st.  
                                                    (Previously announced)

On May 15th, 2011, we conducted sampling to evaluate the spread of 
radioactive materials to the ocean which were detected at Fukushima Daiichi 
Nuclear Power Station. Since the radioactive materials were detected as 
shown in the attachment, today, we informed NISA and the government of 
Fukushima Prefecture of the results.

Yesterday, we took samples of lower water at five points in addition to 
upper water which we normally collect samples of.

We will continuously conduct the similar sampling. 

 
attachment1: Results of Nuclide Analysis of Seawater(PDF 16.0KB) 
attachment2: Radioactivity Density of Seawater(PDF 57.2KB)