On March 28th 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 13th, 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 Analysis of Sub-drain(PDF 51.3KB) 
Appendix2:Radioactivity Density of Sub-drain(PDF 45.5KB)