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Top > Releases ・ Announcements > Fukushima Daiichi NPS Prompt Report > 2013 > Paddle Found at the Large Carry-in Entrance (Inside the Building) on the First Floor of Unit 2 Turbine Building at Fukushima Daiichi NPS (First issue, the follow-up information 1 and 2)

Fukushima Daiichi NPS Prompt Report 2013

Fukushima Daiichi NPS Prompt Report (Dec 18, 2013)Paddle Found at the Large Carry-in Entrance (Inside the Building) on the First Floor of Unit 2 Turbine Building at Fukushima Daiichi NPS (First issue, the follow-up information 1 and 2)

At around 11:00 AM today (on December 18), a TEPCO employee found a paddle on the concrete floor near the large carry-in entrance (inside the building) on the first floor of Unit 2 Turbine Building at Fukushima Daiichi NPS.
The range of the paddle is approx. 4m x 1.5m x 1mm, and no expansion has been observed.
The site status is currently being confirmed.

Transfer line from well point between Unit 1 and 2 to Unit 2 Turbine Building was suspended at 11:40 AM, while pumping up of groundwater from the well point between Unit 1 and 2 was suspended at 11:50 AM just in case, since this transfer line locates near the paddle.
We removed and examined a heat insulator of this transfer line, and found no trace of leakage.
Since neither leakage nor abnormality has been found after water transfer from well point between Unit 1 and 2 to Unit 2 Turbine Building was restarted on 12:51 PM, pumping up of groundwater from the well point between Unit 1 and 2 was restarted on 1:15 PM.
The paddle does not reach sandbags which are installed at the large carry-in entrance, so the water has not flowed outside of the building.

The results of dose equivalent rate measured in this paddle are as follows:
<Surface dose rate> (measured 10cm distance from the paddle)
- γ ray: 0.30mSv/h (1cm dose equivalent rate)
- β ray: 0.05mSv/h (70μm dose equivalent rate)
<Ambient dose rate> (measured 100cm distance from the paddle)
- γ ray: 0.08mSv/h (1cm dose equivalent rate)
- β ray: 0.00mSv/h (70μm dose equivalent rate)

The dose equivalent rate of the paddle is almost the same as that of floor surface, and nuclide composition ratio of the paddle and the floor surface is similar as we measured surface contamination with smear method.
Judging from those, the paddle is estimated to be affected by contamination on the floor surface, and will be wiped off.

Later at the site investigation, water was found to be dropping from the ceiling of the large carry-in entrance (inside the building), but the water is estimated to be rainwater since this ceiling is the roof of the Turbine Building.


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