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information about Fukushima published in English in Japanese media info publiée en anglais dans la presse japonaise

No.3 endoscopy (2)

October 21, 2015

TEPCO for 1st time studies inside No. 3 containment vessel at Fukushima plant

http://ajw.asahi.com/article/0311disaster/fukushima/AJ201510210039

 

THE ASAHI SHIMBUN

More than four years after the triple meltdown, Tokyo Electric Power Co. on Oct. 20 got its first look inside the containment vessel of the No. 3 reactor at the Fukushima No. 1 nuclear plant.

Images from an industrial endoscope inserted into the containment vessel along a wall confirmed no damage to pipes and other equipment, according to TEPCO.

The early survey results for the days-long study also found radiation levels inside the containment vessel were 1 sievert per hour, a reading too high for humans to work there.

TEPCO also said 6.4 meters of water had accumulated on the bottom of the containment vessel, which was in line with the utility’s estimate.

Water temperatures were 33 to 35 degrees and air temperatures were 26 to 27 degrees inside the vessel, according to TEPCO.

The survey is being carried out to prepare for the eventual extraction of melted fuel from the containment vessel.

TEPCO carried out endoscope surveys at the containment vessels for No. 1 and No. 2 reactors in 2012. The radiation level at the No. 3 reactor was lower than those at the No. 1 and No. 2 reactor buildings.

 

 

October 21, 2015

First images of Fukushima plant's No. 3 reactor vessel interior captured

 

A camera sent inside the No. 3 reactor containment vessel at the Fukushima Nuclear Power Plant on Oct. 20 -- the first time since a March 2011 reactor meltdown -- captures an image of scaffolding and pillars, as well as ripples in the water pooled at the bottom. (Photo courtesy of TEPCO)

http://mainichi.jp/english/english/newsselect/news/20151021p2a00m0na008000c.html

 

FUKUSHIMA -- Tokyo Electric Power Co. (TEPCO) on Oct. 20 captured the first images from inside the Fukushima No. 1 Nuclear Power Plant's No. 3 reactor containment vessel since a triple meltdown at the power station in March 2011.

(Scroll down for video)

広告

On the morning of Oct. 20, TEPCO inserted two cameras equipped with both a dosimeter and a thermometer through a hole in the containment vessel wall. Radiation levels inside the vessel proved to be extremely high, at a maximum of approximately 1 sievert per hour. Radiation-tainted water pooled at the bottom of the vessel was about 6.5 meters deep -- close to a previous TEPCO estimate.

 

An image captured by a camera sent inside the No. 3 reactor containment vessel at Fukushima No. 1 Nuclear Power Plant for the first time since the reactor's 2011 meltdown. (Photo courtesy of TEPCO)

Click to enlarge

Meanwhile, at 26-27 degrees Celsius, temperatures inside the vessel were higher than temperatures outside, and water temperatures were between 33 and 35 degrees.

While the cameras captured scaffolding used for pipework inspections, no evidence of damage to the vessel structure could be confirmed within the camera's field of vision. At times, static interfered with the images due to the high radiation levels. A mud-like substance could be seen spreading inside the contaminated water when the cameras moved.

Two camera-equipped robots were dispatched inside the nuclear power plant's No. 1 reactor containment vessel in April to obtain images and data. Another robot was sent to check the inside of the No. 2 reactor in 2012, but the latest inspection marked the first time a camera was sent inside the No. 3 reactor.

TEPCO is set to collect radiation-tainted water from the containment vessel as early as Oct. 22 to analyze the concentration of radioactive substances in the water.

 

An image captured by a camera sent inside the No. 3 reactor containment vessel at Fukushima No. 1 Nuclear Power Plant for the first time since the reactor's 2011 meltdown. (Photo courtesy of TEPCO)

 

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