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 1, 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.
Regarding 12 sampling points at offshore area that were planned to be taken
yesterday, we conducted sampling only 6 points at offshore area due to bad
weather.
We will continuously conduct the similar sampling. 
attachment1: Nuclide Analysis Results of Seawater(PDF 110KB)
attachment2: Radioactivity Density of Seawater(PDF 46.4KB)
