On March 21, 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-Taiheiyou-Oki 
Earthquake. Therefore, we informed Nuclear and Industrial Safety Agency 
(NISA) and the government of Fukushima Prefecture of the results. 
Since March 22, 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 26). 

Since April 17, we have also conducted sampling surveys at four points (2 
points have been added since April 26, another 3 points since April 30, and 
another 1 point since May 5, 10 points in total) 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.
Also, we added another 4 points off the shore since May 27 and 3 points off 
the shore since June 2.

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. 
                                                      (Previously announced)

On August 2, 2011, we conducted sampling to evaluate the spread of 
radioactive materials to the ocean. As a result of nuclide analysis, no 
radioactive materials were detected as shown in the attachment.
Since we conducted closure works by steel sheet pile around the south area 
of open channels of Units 1 to 4 yesterday, we increased frequency of 
sampling in order to monitor environmental impacts of the work. 

Regarding 13 sampling points at offshore area that were planned to be taken 
yesterday, we conducted sampling only 5 points at offshore area due to bad 
weather. 

We will continuously conduct the similar sampling. 

attachment1: Nuclide Analysis Results of Seawater(PDF 13.6KB) 
attachment2: Radioactivity Density of Seawater(PDF 42.4KB)