Important Report from TEPCO

The Tokyo Electric Power Company, Incorporated, would like to make comments on subjects that are reported by the newspapers, TV or websites.

We have confirmed that the water level of accumulated water inside of Primary Containment Vessel, Unit 2 is approx.60cm from bottom of the vessel, concluding that the inside of the vessel is cold enough.

April 5, 2012

On March 26, investigating inside of the PCV of Unit 2 by means of the industrial endoscope, it was confirmed that the water level was 60 cm from the bottom of the PCV, the water temperature was in the range of 48 to 50 ℃, and that the atmospheric temperature on the water surface was in the range of approx. 42 to 45 ℃. Some media reported, "the water level inside the PCV was only 60cm from the vessel's bottom," in spite of water injection to the vessel at the rate of 9m3/h. The level was lower than expected. But what is important here is twofold:
· It was visually confirmed using the industrial endoscope, not estimated from the outside of the vessel, that there was indeed accumulated water inside the Unit 2's PCV. In addition, the temperature of the water inside was measured using the thermometer calibrated outside.
· If the fuel which was melted down to the bottom of the vessel was not fully immersed in the water, the temperature inside the vessel should have been higher than measured this time. The measured water temperature as well as the atmospheric temperature show that the inside of the vessel has been cold enough.
While it is true that the water which was injected at the rate of 9m3/h was leaked from inside the vessel to the reactor building and to the turbine building, there has been no leakage of the water from each building to groundwater. We, TEPCO, will continue to stably operate the circulating injection cooling system which retrieves the leaked water from the turbine building, removes radioactive materials and salt out of the water, and injects it into the reactor again. By doing this, we make it sure to keep the cold shutdown status. We plan to suppress the leakage by various measures, including to check the degree of damage at torus room located on the first basement floor of the reactor building employing robots and to develop construction methods to block w ater among buildings.

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