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 of sub-drains, per the instruction from Nuclear and 
Industry Safety Agency (NISA) on April 14, we will continue the same kind 
of sampling surveys three times a week, and inform the result on the next 
day of the survey.
                                                   (Previously announced)
 
We collected samples from sub-drains (subsurface water obtained and managed 
in the site) near the turbine buildings of Fukushima Daiichi Nuclear Power 
Station collected on October 14, and conducted nuclide analysis. As a 
result, radioactive materials were detected as shown in the appendix. 
 
Also, as the result of analyses on tritium, all alpha-radioactivity and all 
beta-radioactivity in the underground water sampled on September 12, 
tritium and all beta-radioactivity were detected as shown in the attachment.
 
Today, we reported the results to NISA and the government of Fukushima 
Prefecture. 

Appendix1: Result of nuclide analysis of sub drain of Fukushima Daiichi NPS 
                                                               (PDF 10.3KB) 
Appendix2: Result of nuclide analysis of sub drain(PDF 10.3KB) 
Appendix3: Radioactivity Density of Sub-drain (PDF 22.2KB)