Press Releases 2013

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 nuclear power stations (Fukushima Daiichi and Fukushima Daini).

* 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

- During the reliability improvement work to be implemented on Unit 3 feed water system scheduled in March, the reactor water injection from the feed water system is planned to be suspended. In prior to the reliability improvement work implementation, water injection from the feed water system was suspended with all amount injected from the reactor core spray system for the purpose of confirming that there is no significant impact on reactor cooling. At 2:22 PM on February 25, the amount of water injection from the feed water system was decreased from approx. 2.0m³/h to 0m³/h and the amount of injection from the reactor core spray system was increased from approx. 3.5m³/h to approx. 5.5m³/h. As no significant fluctuation was found with the cooling conditions of the reactor, etc., reactor injection water amount was adjusted as follows at 5:25 PM on February 27. Feed water system: Increased from 0m³/h to approx. 2.0m³/h, reactor core spray system: Decreased from approx. 5.5m³/h to approx. 3.5m³/h. At 10:09 AM on March 3, Unit 3 reactor injection water amount was adjusted as follows in order to perform the reliability improvement work. Feed water system: Decreased from approx. 1.9m³/h to 0m³/h, reactor core spray system: Increased from approx. 3.5m³/h to approx. 5.5m³/h.

- At around 11:14 AM on March 3, a TEPCO employee on patrol found groundwater leaking from the drain receiver for the regular reactor water injection pump on the hill (B) at Fukushima Daiichi Nuclear Power Station to the ground (asphalt). The cause of the leakage is assumed to be the drain hose connected to the drain receiver being closed as it was obstructed by materials which led to the inability to drain groundwater. As a result, groundwater which overflowed from the drain receiver leaked onto the ground. After the drain hose was repositioned to improve the condition, the leakage from the drain receiver was confirmed to have stopped at 11:33 AM. The area affected by the leakage was approx. 2mx4mx1mm and the amount of leakage was approx. 8L. The leaked water is kept within the dam by sandbags and has not flowed to the outside. The atmosphere dose rates measured at the leakage location are as follows. γray: 0.12mSv/h, γ+βray: 0.15mSv/h. The radioactivity density analysis results of the leaked water are as follows. Cesium-134: 4.1x10^-2Bq/cm³, cesium-137: 9.0x10^-2Bq/cm³, stibium-125: 1.8x10^-1Bq/cm³. The incident has no impact on reactor water injection.

- At 2:43 PM on March 3, Units 1-2 reactor injection water amounts were adjusted as follows since the amounts had fluctuated.
[Unit 1] Feed water system: Increased from approx. 2.3m³/h to approx. 2.5m³/h, reactor core spray system: Increased from approx. 1.9m³/h to approx. 2.0m³/h.
[Unit 2] Feed water system: Increased from approx. 1.9m³/h to approx. 2.0m³/h, reactor core spray system: Increased from approx. 3.3m³/h to approx. 3.5m³/h.

[Fukushima Daini Nuclear Power Station]
･ Unit 1 to 4: Shutdown due to the earthquake.

* Revised past progress

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