Saturday, June 30, 2012

#Fukushima I Nuke Plant Reactor 4 Spent Fuel Pool Cooling System Update from TEPCO: UPS Broken


(UPDATE) TEPCO managed to bypass the UPS and restarted the cooling system at 3:07PM on July 1. At the time of the restart, the temperature of the water inside the Spent Fuel Pool was 42.9 degrees Celsius. TEPCO plans to replace the faulty UPS this week. (From the tweets of another independent journalist who receives TEPCO email.)

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Independent journalists who cover TEPCO's press conference posted TEPCO's email updating them about the problem in the Reactor 4 SFP cooling system that automatically shut down on June 30, as follows (I got the text from Yasumi Iwakami's tweets):

【福島第一原子力発電所4号機使用済燃料プール代替冷却システムの自動停止に関する本日の調査結果】6月30日19時40分。「現場にて調査を行った結果、UPS(無停電電源装置)に問題があると推定されたことからUPSのバイパスなどを検討しており、復旧作業については明日、準備が整い次第、実施する予定。なお、午後6時現在のプール水温度は36.6℃(仮設温度計の指示値)で、使用済燃料プール水の温度が保安規定上の管理温度の上限である65℃に達するまで、約60時間と予測しております。

Today's investigation of the automatic shutdown of the Fukushima I Nuclear Power Plant Reactor 4 Spent Fuel Pool cooling system, as of 7:40PM on June 30, 2012:

We conducted the investigation at the site, and there seemed to be a problem with the UPS (Uninterruptible Power Supply). We are considering bypassing the UPS, and the work to restore the system will start tomorrow as soon as we are ready. The temperature of the pool as of 6PM [on June 30] was 36.6 degrees Celsius. We estimate that it will take about 60 hours for the water temperature of the Spent Fuel Pool to reach the upper limit of the safety regulations at 65 degrees Celsius.


That gives TEPCO until 6AM on July 3 to fix the problem. TEPCO already said they didn't find any leak.

Sankei Shinbun has additional details (6/30/2012; part):

東電が現場を調べたところ、主電源と冷却装置をつなぎ、非常時に電力を供給する無停電電源装置(UPS)が故障したとみられる。

TEPCO investigated the site, and said that the UPS (Uninterruptible Power Supply) may have broken. The UPS is connected to the main power supply and the cooling system, and provides electricity in an emergency.

冷却装置は貯蔵されている燃料を冷やすためプールの水を引き出して、冷却し再びプールに戻す仕組み。2系統あり、予備系統の装置を起動させて冷却を再開させようとしたが、2系統とも同じUPSを使用していたため再開できなかった。東電はUPSを迂回(うかい)させて冷却を再開する方針。

In order to cool the fuel stored in the Spent Fuel Pool, the cooling system draws water from the pool, cools the water and circulates it back into the pool. There are two lines, and TEPCO tried to resume the cooling operation by starting the backup line. However, since both lines use the same UPS, TEPCO couldn't restart the system. TEPCO is planning to bypass the UPS and restart the system.


There are rumors (like the one from Professor Takeda) that the Reactor 4 SFP is mechanically damaged because of shoddy construction. I have no idea what the basis is for Professor Takeda's assertion that shoddy construction work damaged the pipe of the cooling system. They seem as baseless as the rumors that everything is dandy or that the building is listing like the Tower of Pisa.

The worker who tweets from Fukushima I Nuke Plant tweeted this about the problem:

こんにちは(^O^)さっきオイラにフォロワーさんから「いま4号機の噂が…」ってDM来てビックリしたんだけど、オイラ達機械屋さんに呼び出しはかかってないでし。どうやら制御系トラブルみたいでし。修理は部品手配もあるし明日以降かなぁ…。とりあえず温度上昇傾向から見て考えても大丈夫でし。

Hello. I was surprised by DM [twitter's direct message] from one of my followers saying "Right now, the rumor of Reactor 4..." At least mechanical engineers like me haven't been called in. It looks like a problem with the control system. Repair will probably be tomorrow, as they need to arrange for the repair parts. For the time being, looking at the temperature trend, I don't think there is anything to worry.

ホントにヤバい状況ならオイラ達には必ず緊急呼び出しかかるでし。あと待機してるキリンが出動するでし。その時はオイラが必ず速攻つぶやくでしから。オイラはプリン食べて普通に休み満喫中でし。でわでわ。

If it is really a serious situation, we would receive an emergency call. Then the crane will be used [Putzmeister concrete crane that pours water directly into the Spent Fuel Pool]. If that should happen, I will tweet right away. But I'm enjoying my day off, eating sweets. See ya.


19 comments:

Anonymous said...

The data sets are indicating that prior to July 10th {ed note: error rate is 3 days plus or
minus} the tone relative to the [ongoing Fukushima disaster] will change to one of [conflict] and [trouble] just as the [disaster] word shifts within the [public consciousness] over to [catastrophe], or [cataclysm].

PD All the above material is copyrighted
http://halfpasthuman.com/

Anonymous said...

it looks like the REAL "un-interruptible power supply"
is actually a big pool with certain elements inside.
-
pre-fukushima, didn't they have solarcells on the common spent-fuel-pool storage building?

Anonymous said...

I can't resist.

First the "Containments" cannot contain....

Now the "Uninterruptible Power Supply" got interrupted...

When I finally leave Japan, will I pay that last TEPCO bill or not....

Anonymous said...

OCCUPY OI is here: http://www.nihon.jpn.org/ooi/

Apolline said...

Almost OT :

How many cameras on Fukushima site ?

http://www.youtube.com/watch?feature=player_embedded&v=dNRgJHRxRW8#!

Anonymous said...

rumor in #fukushima can this be confirmed about a explosion at number 4 reactor

Anonymous said...

They've already bypassed the broken UPS and circulation has been restarted already as of 2:35 or something. There are no rumors of explosion. Reminds me of the hysteria a few months ago when everybody was freaking out about helicopters in Tokyo.

There is a real story about cesium in the urine of 141 kids in Fukushima. Primavera you might want to give that one a bit of attention.

Anonymous said...

According to the temperature data they are releasing, it would seem the pool temperature increases around 0.25ºC per hour instead of 0.5ºC.

Atomfritz said...

Redundant supply lines, and a single UPS that makes both fail at the same time?
Another stupid design flaw.

Anonymous said...

@1:01
thanks for the link
Occupy Nuke Everywhere

@2:08
Hysteria, rumors, freaking out, oh well.
Good, something else that broke got fixed and the Putzmeister stands near.

Relieved that the "listing" #4 was being structurally reinforced from below (but not reported until later),while the "rumor and hysteria" appeared as we common folk tried to understand the problems with limited information.

"Freaking out" ?
An enormous level of concern and anger for the children stranded in contaminated areas wearing dosimeters and a complete disregard from any government or industry official for their welfare.

Is it unreasonable for a population experiencing this level of continuing disaster to want to know why there is a sudden appearance of helicopters overhead?
Not so much

Anonymous said...

Over reacting to limited information about a disaster of this nature is better than no reaction at all. Stop putting people down for being concerned and afraid. I'm disappointed in you for this tone. Why do you attack the few people who try to inform with the limited information they are getting from Japan like Arnie Gundersen? When he talked about building 4 leaning, the top of it was leaning. That was months ago and at that time the upper part of building 4 was leaning and Tepco has since removed the part that was indeed leaning. Now Arnie is being treated like a bad guy. Oh, how we are manipulated by the fascist pro-nukes.

Susan said...

TBS/JNN live cam blank again this morning Mon. July 2, 6am Japan time.
http://www.youtube.com/embed/nQLtkl5gDGA
Must be "fixing" something they don't want us to see?

Anonymous said...

Oh god, not another Arnie apologist. The top of Unit 4 was not leaning for the simple fact that the top of Unit 4 was blown off in an explosion. I'm starting to think the "Unit 4 is leaning" legend was started by Tepco in order to take attention away from Units 1, 2, and 3 (the ones with actual blobs of melted nuclear fuel).

There are three meltdowns underway, and people are distracted by the mysteriously leaning #4 and by helicopters in Tokyo. Kids in Fukushima are showing up with cesium in their systems, but people are more interested in propping up Arnie Gundersen's claims that Unit 4 is leaning.

Anonymous said...

Beyond Nuclear people are worse. And they've been at it even though they sorely lack experience (other than anti-nuke activism) or knowledge or degree on nuclear science or engineering.

Anonymous said...

Anon at 2:11PM, the top part (operation floors) was not leaning, and that's not the reason why they've been removing the debris and structures.

Several locations on the lower exterior walls are "bulging" but I don't think that means "leaning". And those bulges are well within what's allowed in the building code as "straight".

You could repeat the refrain that "TEPCO lies". So? Gundersen and his supporters are free to show their data. They could at least interpret the data as presented and refute it.

Anonymous said...

Don;t know if its official but TEPCO may advise they are replacing with a IPS (interruptible power supply) - they will guarantee it will be more reliable.

Phew thanks god - hoping they didn;t try and fit another second hand UPS from another reactor - maybe Ohi had a spare one ... ?

Anonymous said...

Also have had issues obtaining duct tape and band aids in Japan - also a distinct shortage of apprentice electrical & design engineers - but do have an extreme over supply of competent safety engineers - saw a group of them (old ladies and young kids - near the protest site) - GO FIGURE?

Anonymous said...

RE: pre-fukushima, didn't they have solarcells on the common spent-fuel-pool storage building?

Probably did but deemed better to replace with a UPS/competitive local "reliable/clean/cheap no C02 energy supply key reasons"

1) 35+ year history without an accident (1975-2010)
2) Much cheaper price
3) Supporting Fukushima / Tokuhu recovery efforts
4) May have had some electoral or political pressure

Anonymous said...

5) maybe diaiichi 5&6 are getting back to operational safety?

RE: or knowledge or degree on nuclear science or engineering.

Take your nuke shill mantra else where NO nuke is GOOD nuke!

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