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 have been added since April 26, another 3 points since April
30th, 9 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 (Regarding 6 points in 9 points of 3km
off the shore, from May 9th, we conduct sampling at the lower layer in
addition 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.(Previously announced)

On May 16th 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: Results of Nuclide Analysis of Seawater(PDF 17.9KB) 
 attachment2: Radioactivity Density of Seawater(PDF 71.9KB)