Status of TEPCO's Nuclear Power Stations after the Tohoku-Chihou-Taiheiyou-Oki Earthquake (Daily Report as of 3:00 PM on August 12)

Due to the Tohoku-Chihou-Taiheiyou-Oki Earthquake which occurred on March 11, 2011, TEPCO's facilities including our nuclear power stations have been severely damaged. We deeply apologize for the anxiety and inconvenience caused.
With regard to the accident at Fukushima Daiichi Nuclear Power Station, on April 17, 2011, we have compiled the roadmap towards restoration from the accident and on July 19 we accomplished the Step1 target "Radiation dose is in steady decline". Then on December 16 we confirmed the accomplishment of the Step 2 target "Release of radioactive materials is under control and radiation doses are being significantly held down".
In addition, on December 21, 2011, we have compiled the "Mid-to-long-Term Roadmap toward the Decommissioning of Fukushima Daiichi Nuclear Power Units 1-4, TEPCO".
In addition to the maintenance of the plant's stable condition, we will implement Mid-to-Long Term countermeasures towards the decommissioning of Fukushima Daiichi Nuclear Power Units 1-4 to enable evacuees to return to their homes as soon as possible and reduce the anxiety of the people in Fukushima and the whole nation as soon as possible.

Below is the status of TEPCO's Fukushima Daiichi Nuclear Power Station.

* The updates are underlined.

[Fukushima Daiichi Nuclear Power Station]
· Unit 1 to 4: Abolishment (April 19, 2012)
· Unit 5 to 6: Outage due to regular inspections before the earthquake

-Contaminated water transfer from the underground reservoirs was all completed as of July 1. However, we are continuing to take measures to prevent the expansion of contaminated water, and to conduct sampling activities.

<Measures to prevent the expansion of contaminated water>
· Since the decreases of all-β radioactivity densities in the leakage detection holes (at the northeast side of the underground reservoir No.1, the northeast side of the underground reservoir No.2, and the southwest side of the underground reservoir No.3) have been slow, operations to dilute the underground reservoirs No.1-No.3 by transferring filtered water or desalination-system (RO) treated water (the all-β radioactivity density: approx. 1×10¹Bq/cm³) into these reservoirs have been conducted as appropriate.
[Recent dilution operations]
Underground reservoir No.1 (since June 19): On August 3, approx. 60m³ of filtered water was injected.
Underground reservoir No.2 (since June 27): On August 1, approx. 60m³ of filtered water was injected.
Underground reservoir No.3 (since July 24): On August 11, approx. 51m³ of water in the drain hole (northeast) of this underground reservoir was injected.

· On August 11, leaked water in the leakage detection holes at the underground reservoirs No.1-No.3 was transferred to the temporary aboveground tank, and leaked water in the drain holes at the underground reservoirs No.1 and No.2 was transferred into these underground reservoirs.

<Sampling>
On August 11, sampling was performed in the drain holes of the underground reservoirs No.1-No.7 (14 locations), the leakage detection holes of the underground reservoirs No.1-No.4 and No.6 (sample could not be collected at 2 out of 10 locations), and the observation holes of the underground reservoirs (22 locations). The analysis results showed no significant change compared to the results from the previous sampling (on August 10).

-We installed observation holes east of the Unit 1-4 Turbine Buildings, and have been conducting sampling and analysis of groundwater from the observation holes. On June 19, we announced that tritium and strontium were detected at high densities in the observation hole located between Units 1 and 2. Therefore, we have been conducting intensified monitoring.

· At 2:10 PM on August 9, we started pumping up groundwater from the water collection pit (south) installed east of Units 1 and 2 Turbine Buildings and transferring the pumped-up groundwater to the Unit 2 vertical shaft C.

-At 10:06 AM on August 5, accumulated water transfer from the Unit 2 Turbine Building basement to the Unit 3 Turbine Building basement was started. At 9:38 AM on August 12, the transfer was stopped.

-At around 12:33 PM on August 12, an alarm indicating a high radioactivity density went off at the continuous dust monitor installed in front of the Main Anti-earthquake Building. Due to this, at 12:48 PM on the same day, an instruction was given to put on masks in the areas where the wearing of full-face (or half-face) masks is not required in the power station site. Neither abnormality in the plant data (reactor injection water amount, spent fuel pool water temperature, etc.) nor significant change in the monitoring post data and in the readings of continuous dust monitors installed at other locations was found. We therefore consider that this incident has no impact on the outside of the power station. Meanwhile, we provide water mist spray in front of the Main Anti-earthquake Building to prevent heat stroke, and the contamination measurement conducted through the exit monitor at the Entrance Area Management Building found out that 10 people who had been waiting for a bus in front of the Main Anti-earthquake Building had contamination on their bodies. As their heads and faces were found contaminated (with the maximum dose being approx. 19Bq/cm²), these people were instructed to receive whole body counting. At 1:25 PM on the same day, the mist generator was stopped since we suspected that the contamination of the bodies may be attributable to contamination of mist generated by the mist generator. Further, since water (for lavatories, etc.) used in the Main Anti-earthquake Building and Units 5 and 6 comes from the same water source as water supplied to the mist generator, use of water for lavatories, etc, was prohibited at 1:16 PM on the same day. At 1:40 PM on the same day, the main valve of water supplied to the mist generator and water used in the Main Anti-earthquake Building and Units 5 and 6 was shut off.

* Revised past progress

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