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Corporate Information

 
Press Release (Apr 04,2011)
Improvement plan for the exact nuclide analysis at the site ofFukushima Daiichi Nuclear Power Station under instruction of NISA
 At the site of Fukushima Daiichi Nuclear Power Station, as part of our
investigation for the pathway and the volume of emission, which contains
radioactive material, we have been conducting nuclide analysis for air
inside the plant, seawater near the plant and water puddle in the
turbine building. We have been informing you the result of the nuclide
analysis. It is ascertained that the result of nuclide analysis of
tellurium 129 (half life : about 70 minutes) conducted on March 30th, for
water puddle collected near the trench and ground water collected near
the turbine building are doubtful.

 We were severely warned orally by Nuclear and Industrial Safety Agency
(NISA) for this matter.

 We seriously take NISA's severely warn and endeavor to conduct proper
assessment for nuclide analysis.

 The causes of mistakes for the assessment of nuclide analysis and
improvement plan for the exact nuclide analysis are as follows:

(Cause)
 ·Even though the main peak of iodine 134 and cobalt 56 were not
  detected, we determined those nuclide were detected in the sub peak.
 ·For the term of assessment, using germanium device of Germanium
  semi-conductor type nuclide, since tellurium -129m and tellurium -129
  were not registered as parent-daughter nuclide information (library),
  we could not conduct calculation considering the creation from parent
  nuclide.

(Improvement plan)
○Implementation of analysis work following the opinion from third party
   ·We confirm the way of analysis such as detection accuracy based on
    the specialty of appliances with experts from manufacturers.

○Reconstruction of back-up system by other electric power companies
   ·In order to check the data without mistakes, we reconstruct the
    back-up system by other electric power companies.

 We intend to show the result of analysis on radioactive materials in the
air inside the Power Station site, in the water puddle in the turbine
building, in the water inside trenches, and in the underground water near
the turbine building as soon as we prepare based on this policy.

(Analysis result of radioactive material to be verified)
   ·Air inside the Power Station site
    released document from March 22nd to March 31st
   ·Seawater near the Power Station
    released document from March 22nd to March 31st
   ·Water puddle in the turbine building
    result of March 25th and 27th
   ·Water in the trench
    result of March 30th and 31rth
   ·Underground water near the turbine building
    result of March 31st

 The result of sampling survey implemented by TEPCO is released on the
next day as we do now. In addition, three nuclides (Iodine-131,
Cesium-134 and Cesium-137) that affect more for radioactivity and easy to
identified are to be published as fixed figures.
 Other nuclides figures are to be released as soon as identified. 
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