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 July 27, 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.

We will continuously conduct the similar sampling. 

attachment1: Nuclide Analysis Results of Seawater(PDF 13.8KB) 
attachment2: Radioactivity Density of Seawater(PDF 42.5KB)