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 are added since April 26, another 3 points from April 30th,
total of 9 points) 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 added 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 based on the improved measures for recurrence prevention
which have been prepared in accordance to a warning from NISA on April 1st.
On May 13th, 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.
However, we conducted sampling out of 4 points of 17 points off the shore
as planned yesterday due to the weather.
We will continuously conduct the similar sampling.
attachment1: Results of Nuclide Analysis of Seawater(PDF 18.4KB)
attachment2: Radioactivity Density of Seawater(PDF 32.9KB)