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, 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 September 2, and conducted nuclide analysis. As a 
result, radioactive materials were detected as shown in the appendix. 
Also, we analyzed peritoneum and strontium contained in the water of 
sub-drains sampled on August 15, 2011 and as a result we have detected 
strontium 89 and 90 as shown in the appendix.

Today, we reported the results to NISA and the government of Fukushima 
Prefecture. 

Appendix: Result of nuclide analysis of sub drain of Fukushima Daiichi NPS 
                                                               (PDF 10.3KB) 
Appendix1: Pu analysis result at sub-drains of Fukushima Daiichi Nuclear 
           Power Plant (PDF 7.89KB) 
Appendix2: Result of nuclide analysis of sub drains at Fukushima Daiichi 
           Nuclear Power Plant (PDF 10.5KB) 
Appendix3: Radioactivity Density of Sub-drain (PDF 22.8KB)