Wednesday, April 18, 2012

Fukushima Event: Inspection of Suppression Chamber Unit 2 Full of RadioWater March 15, 2012

Event: March 15 Inspection of Pressure Suppression Chamber No. 2
[Fukushima NukeBlog Index]

Tepco handout

Planned radiation exposure:
Min. (0.67 mSv ) planned: 10mSv ( Max. 2.87

Spatial Radiation Dose in the Building (4)
Floor of middle basement     20-30  15-30  15-20
Front of door to torus room  20-35   20    50-75
*Inside torus room           130-160 100-130 NA
*Surface of water            150-160  150    140 

* 130-160 is VERY HIGH, 1000 will give radiation sickness or death. Not clear how workers would measure 130-160 msv/hr and only get 10mSV of exposure.

Unit 2 torus pictures show water almost up to the roof of the lowest level below stairs

unit 3 pictures also show water almost up to the roof of the lower level

from, link to original japanese article no longer exists

Thursday, March 15, 2012

No cracks or strains seen in suppression chamber of No. 2 reactor at Fukushima plant

Tokyo Electric Power Co. (TEPCO) took and released photographs on March 14 of the pressure suppression chamber of the No. 2 reactor at the crippled Fukushima No. 1 Nuclear Power Plant and the utility said there were apparently no cracks in the chamber or no changes in the shape of the device.

It is the first time TEPCO, the operator of the troubled nuclear power station, has taken photographs of the interior of a pressure control chamber at the troubled Fukushima nuclear plant since the outbreak there of the ongoing crisis. "Apparently, there were no cracks in the suppression chamber and there were no changes in the shape."

The pressure suppression chamber is designed to turn steam in the reactor into water to be used for cooling. In order to identify places to which coolant water leaked from the reactor or underground water flowed to, TEPCO planned to check the inside of a doughnut-shaped pressure suppression pool called "the torus," which houses the pressure suppression chamber. TEPCO took the photographs of the pressure control chamber as part of its preliminary survey for the plan. Read More

Dailymotion video post: 

My re-translation: From Japanese television station coverage. 
Brave TEPCO workers took video camera for the first time into the basement of the building containing the Unit 2, Fukushima Daiichi nuclear power plant. This contains the pressure suppression chamber where the giant torus (donut) structure is flooded with water. The color change in the middle of the stairs is contaminated water which is 5 m (about 15 feet) in depth. The radiation dose of the water was measured at an alarming 150 to 160 mSv per hour. That is about 1/8 the 1000 mSv which can cause radiation sickness or eventual death within minutes of exposure. 
No. 2 was the only building of 1-4 that was left visibly undamaged at  the Fukushima Daiichi nuclear power plant. From midnight on March 14 last year for 15 days large clouds of steam and water vapor containing radioactive material were seen coming out of the opening in the wall.
Radiation doses were seen soaring in the city, such as villages and Fukushima area  far away from  around the nuclear power plant right after this. TEPCO has been investigating possible damage to the containment and pressure suppression chamber.

original google translations: 
Pressure suppression chamber No. 2 Fukushima Daiichi nuclear power plant has seen 20,120,315 camera

Pressure suppression chamber No. 2 Fukushima Daiichi nuclear power plant has seen 20,120,315 camera by PMG5

This shows how workers entered the catwalk on top of the torus, and stairs leading into water

This shows the stairway leading into contaiminated water

After he opens up the door, this is the stairway to catwalk on top of torus

Compare to this TEPCO schematic that shows water flooding the interior of the torus and about halfway up the outside.

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