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 5, 2011, we conducted sampling to evaluate the spread of
radioactive materials to the ocean which were detected at Fukushima
Daiichi Nuclear Power Station. As a result, radioactive materials were
detected as shown in the attachment. Therefore, we informed Nuclear and
Industrial Safety Agency (NISA) and the government of Fukushima Prefecture
of the results.
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 around the south area of open channels in order to monitor
environmental impacts of the work. 
We have cancelled 6 off-shore points of sampling to be conducted yesterday,
due to the bad weather. 
We will continuously conduct the similar sampling. 

attachment1: Results of Nuclide Analysis of Seawater(PDF 12.9KB) 
attachment2: Radioactivity Density of Seawater(PDF 21.7KB)