Monday, September 8, 2014

Video Showing #Fukushima I NPP Reactor 3 Operating Floor's Heavily Damaged Northwest Section

I happened on this 25-minute video in TEPCO's video archive (Japanese), instead of the usual Photos and Videos Library. There is no document explaining the purpose of the video or the findings from the video.

It focuses on the heavily-damaged northwest corner of the Reactor 3 operating floor, as you have seen in this aerial view (from TEPCO's photos and videos library, 2/14/2014, red circle added, click to enlarge):

The video camera dips below the shredded metal bars and concrete of the operating floor:

In the video, the section that is covered with metal sheets is where the Spent Fuel Pool is. TEPCO plans to construct a structure over the Reactor 3 building to install the crane and the fuel handling machine to remove the spent fuel assemblies. This video survey is probably related to the plan, to assess the structural integrity of the section in order to build the structure around the building.

Or so I thought at first, until I remembered a togetter I read in August.

What was beneath the operating floor in the northwest section?

One of the people who have diligently followed the news and press conference on the Fukushima I NPP accident, @mtx8mg "koajisashi", has the answer in his/her togetter from 8/10/2014: PLR-MG, or Primary Loop Recirculation System Motor Generator, which occupied almost the entire length of the west side of the Reactor 3's 4th floor:

(H/T @pluedro)

(H/T @mtx8mg)

And what happened there?

"koajisashi" reminds us in the togetter of the March 23, 2011 fire in the Reactor 3 building, with black smoke seen rising vigorously (see my post on 3/23/2011; TEPCO called it "gray smoke"). At that time, the exact location of the fire was not reported, and the time and date when the fire started was not known (or reported) either. Black smoke was seen rising from the Reactor 3 building on and off until the evening of March 23, 2011.

But in the meeting on March 24, 2011, the location of the fire was identified as PLR-MG in Reactor 3's 4th floor. It was never reported by the media, as far as I know. Reading what was reported in the meeting now, I can see why it was not reported back then. According to the meeting report on March 24, 2011 in the NISA archive (translation is mine),


・黒煙の原因と考えられているオペフロ下の MG セットから隣接している SFP の壁まで2m程度。黒煙発生時の熱によって壁の強度の劣化が懸念されるため検討を行った。SFP 壁は厚さが185cm、RC 造で、鉄筋は壁表面にもっとも近いもので8cmの深さにある。鉄筋は300-400℃で影響を受け始めるが、学会の耐火試験データに基づき評価したところ、350℃に達するのは4時間程度の時間が必要であり、壁の強度に大きな影響はないものと評価した。

At 11PM last night [3/23/2011], conducted visual survey and thermography measurement and concluded that the burning had subsided.

The cause of the black smoke is considered to be the MG set [PLR-MG] beneath the operating floor. SFP is about 2 meters away from [part of] the MG set. As there was a worry about deterioration of the SFP wall strength due to the heat generated when the black smoke was rising, we evaluated the data. The SFP wall is 185cm (about 6 feet) in thickness, made of reinforced concrete. The reinforcing bars closest to the surface of the wall are at 8 centimeters from the surface. The reinforcing bars start to be affected by heat at 300 to 400 degrees Celsius. According to the fire-resistance data by the [relevant] scientific society [no mention of which one], it would take about 4 hours [of burning] for the temperature to reach 350 degrees Celsius, and we concluded there would be no major effect on the strength of the SFP wall.

As I wrote above, no one knows exactly how long the MG was burning. In fact, the same NISA meeting report, on March 23, 2011, says the black smoke started to gush out at 4:20PM on March 23, 2011, and as of 9:30 the black smoke was still rising. So the fire may have been burning for at least 5 hours on March 23, 2011.

The news, if the details like these had been reported by the media at that time, should have made people very nervous. And this is probably why TEPCO video-surveyed the area in detail, and also why TEPCO seems very eager to remove the spent fuel assemblies from the Reactor 3 Spent Fuel Pool, despite the mess and damage of the Reactor 3 building.

The structural integrity, not of the northwest section per se, but of the Spent Fuel Pool itself, may be the issue that concerns TEPCO.


Anonymous said...

Those motors at the very end of the video do not show charring.
I know there's been 3 years of rain, but no soot is visible, anywhere.
Electrical wires that would have been close to the fire still have their coatings intact.

And the plates covering the SFP are custom designed?

Pierre Fetet said...

The fire is visible here (webcam pictures, March 23, 2011) : at 16:00, 17:00 and 18:00 :
Nothing the next day.

Dan Zimmerman said...

I put together a full analysis of the damage done to 3 and 4. Both are in the exact location, the northwest corner. If you go back to the original video of the 3 blast you will see that it explodes straight up as if from the barrel of a gun, as opposed to unit 1s blast.

The seismic data is consistent with the idea that the explosion happened underground, below unit 3.

I have put together other extensive data that shows that under Fukushima was a weapons factory.

Sooner or later the world will realize this to be true, as nuclear power was never more than an avenue for nuclear proliferation in countries not allowed to possess the bomb.

Anonymous said...

There was no weapons factory - there was a nuclear reactor set up to run on weapons grade plutonium. You are correct that #3 blew straight up.

This is the first good video I've ever seen of #3. Somebody finally stuck and HD camera in there.

First thing you notice is that the instant they go below the floor, you get tons of radiation - little white streaks and spots. No human will ever set foot in there and live to tell about it.

Look at the video from 18:00 to 23:00 - the camera enters the building on the west side looking east, directly toward the reactor opening. Stop the video at precisely 23:18. Just behind all those flashes of radiation coming at the camera, you can see the large beam in the ceiling of level 4, closest to the camera. You can see a second beam behind it. Behind that beam, where you see a big brown wall riddled with holes, that's a nuclear reactor. Big cracks and big gaping holes in the side of that nuclear containment.

No more mystery here folks. Of course anyone who's studied this accident knows the truth, despite the claims otherwise. Reactor 3 totally failed.

Joffan said...

Thanks for finding this interesting video and your thoughts on the damage & consequences.

The metal plates in the video are over the equipment pool - this is on the left of the opening photo composite - not the spent fuel pool which is on the right. For the two diagrams of lower floors, these needed to be rotated a quarter-turn counter-clockwise to align with the opening photo, so the structurally compromised area is top left of those diagrams.

For damage to the Spent fuel pool from the fire, I guess it depends if PLR-MG A or PLR-MG B was burning. Set A, which is right under the damaged area, is not that near the spent fuel pool. Set B would be the one of concern. The closest we get to PLR-MG B in the video is around 18:00 where there's no immediate signs of fire (despite the explosion damage).

Anonymous said...

Good points, 7:11PM. "Stop the video at precisely 23:18." Looks like vertical-pour concrete panels of the containment 'loosened' from each other.

It was a curious explosion: rebar Totally stripped of its concrete, totally, whereas in ordinary construction debris it's bonded for years. The big beams look to concrete cladded but no visible damage other than cracks which could even be from subsequent demolition.
Totally ductiled stripped rebar and intact concrete cladding for the big beams. ???

Do they have video of the interior of the turbine buildings?

Anonymous said...

TEPCO postulates that the access manhole failed that sits on top and to the side of primary containment near the fuel pool. A rectangular contraption sits over that area in the overhead floor picture. It is the only area that coincides with the blast pattern of the metal roof joists (would exhaust straight up). EXSKF posted a .pdf by TEPCO pointing out suspected failure points and that was one of them.

If you go back and listen to the sounds during Unit 3's eruption, there are more explosions going on than just one.

Japan had a reprocessing plant that never ran longer that a few months at a time because reprocessing is dangerous and complicated. Doubt the aged Daiichi plant was setup to reprocess fuel. Maybe they were extracting Pu from new unused MOX fuel rods but supposedly the local Prefecture (State) had to give permission for the use of MOX fuel but claimed they didn't even know MOX fuel was present at Daiichi.

Anonymous said...

If Tep could be so kind as to film to a similar level below the Operating Floor on the other sides of Containment then perhaps we'd understand those blast mechanics a bit better?, obviously.

Anonymous said...

anonymous 9:55 PM said:

"If you go back and listen to the sounds during Unit 3's eruption, there are more explosions going on than just one."

As far as I know, there is no known recording of the sound of Unit 3's explosion. The sounds in the various videos bouncing around the internet were dubbed in after the fact. The video of the explosion did not capture any sound.

Anonymous said...

The 'MediaInfo' information tagged and embedded in the original Japanese news broadcast of the Unit 3 explosion shows the audio of that video was recorded in stereo. Only the delay in the sound waves reaching the pickup mics or parabolic microphones (within a dish) due to the long distance camera setup is confusing. Besides, witnesses miles away from the blast confirm multiple explosions heard during the event.

TEPCO knew Unit 3 was going to blow, bet there are other videos with sound too that we will never see.

Anonymous said...


"The sounds of the Unit 3 explosion were added after the fact. Gunderson is correct to refer to the video without sound, as that is how it originated. The video was from too far away to have sounds that synchronized with the blast, so a TV station added them and the video with sound has now gone viral. The dead giveaway that these sounds were added is that some are mono and some are stereo. Please see"

Unfortunately, the link in that link is now dead and doesn't show the analysis.

It does not help to understand what happened when somebody adds something that they think should be on the video but wasn't (i.e.: the actual sound of the explosion). Personally, I think it is going to be a long time before the details of the events at Fukushima are determined, due to the high levels of radioactivity at the site. There are many places where humans simply can't go for any length of time. I have to thank our gracious host for keeping this site going as it tracks further developments.

netudiant said...

I do not know how much spin is in this METI press release, but it claims that the ALPS is now working and that they expect to process all the stored water this fiscal year. They also claim only modest harbor pollution.
If true, this would be substantial progress.

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