On March 28 2011, we were advised from Nuclear Safety Commission of Japan 
to enhance sampling surveys regarding water accumulated in underground 
floor of the turbine buildings of Fukushima Daiichi Nuclear Power Station. 
In order to verify any leakages to underground and sea, and safety, we have 
been implementing the sampling surveys of subsurface water and seawater.

Regarding sampling surveys of sub-drains, based on the instruction from 
Nuclear and Industry Safety Agency (NISA) on April 14th, we will continue 
conducting the same kind of sampling surveys three times a week, and inform 
the result on the next day of the survey.
                                                    (Previously announced)

On May 30, 2011, we conducted sampling surveys regarding sub-drains 
(subsurface water obtained and managed in the site) near the turbine 
buildings of Fukushima Daiichi Nuclear Power Station. Today, we reported to 
NISA and the government of Fukushima Prefecture, since, as the results of 
nuclide analyses, radioactive materials were detected as shown in the 
attachment. 

Appendix1: Results of Nuclide Analyses of Sub-drains (PDF 13.3KB) 
Appendix2: Radioactivity Density of Sub-drain (PDF 25.4KB)