Fukushima Daiichi NPS Prompt Report 2013

This is follow-up information regarding the water leak from the underground reservoirs at Fukushima Daiichi NPS.

Regarding the leakage which occurred during water transfer from the underground reservoir No.3 to No.6, the area affected by the water leaked from the connection part of the transfer pump outlet pipe is 2m x 3m on the soil covering the upper part of the reservoir (embankment) near the reservoir No.3 tank man hole. Since the leaked water has been absorbed into the covering soil, there is no possibility of the leaked water flowing out of the site boundary. The amount of leakage is estimated to be approx. 22L (calculation value).

Though the incident has occurred in the controlled area, the condition has been judged to be subject to the application of Article 19-17, Item 10 of the Rule for the Installation, Operation, etc. of Commercial Nuclear Power Reactors (Rule for Commercial Nuclear Power Reactors) ("in the case that leakage of radioactive materials, etc. occurs in the controlled area due to a reactor facility failure or other unexpected incidents") at 2:43 PM on April 11. This incident is reported in accordance with Article 168 of the Technical specification for nuclear reactor facility at Fukushima Daiichi Nuclear Power Station (Report).

< Reference: Underground reservoir No.3 >
Water quality analysis result: 2.9×10⁵ Bq/cm³
Leakage amount: Approx. 22L
Value stipulated by law: 3.7×10⁶ Bq

< Announcement on an emergency press conference>
An emergency press conference will be held at 6:00 PM on April 11 in the meeting room on the third floor of our Head Office. We will explain about the current statuses of the underground reservoirs at Fukushima Daiichi Nuclear Power Station.
At the Corporate Communications Department in Fukushima, the information will be provided at the regular press conference at 6:00 PM on the same day.

Head Office
Date and time: April 11, 2013 from 6:00 PM
Place: Meeting room on the third floor of the Head Office (Reception starts at 5:30 PM)

Fukushima
Date and time: April 11, 2013 from 6:00 PM
Place: Press conference room of the Fukushima prefectural press club on the second floor of the Fukushima Prefectural Government Office Building