#Fukushima I NPP Reactor 3 MSIV: Leak Is From Expansion Joint That Connects to Main Steam Pipe

Just like the survey above the grating on April 23, 2014, TEPCO's workers inserted the pan-tilt camera from the floor above to identify the location of the leak in the MSIV room in Reactor 3 on May 15, 2014. They used a hook to lift a portion of the grating so that the camera could go below the grating.

They found a leak, and it was from the expansion joint that connects to the Main Steam Pipe D, one of the four Main Steam Pipes.

From TEPCO's photos and videos library, 5/15/2014:

Leak was found from the expansion joint to the Main Steam Pipe D, which is in fact hidden from view. What you see in the foreground is the Main Steam Pipe C and the Expansion Joint C. Leak is marked by red circles in the photo (English labels are by me):

So, the MSIV (Main Steam Isolation Valve) itself may have worked exactly as it is designed for, which is to shut off the steam from the reactor in case of a severe accident that would necessitate the scram (we don't know for sure, unless someone enters the MSIV room and investigate), but the leak is from the joint right before the MSIV.

Here's the video, showing the leak (look very closely after 33 seconds):

Bad news, I think, for reactors around the world, but no one in the media has picked up on the significance of the news so far.

This is the typical reporting that I've seen in the Japanese media:

"A leak was found on the Containment Vessel of Reactor 3 for the first time."

Clearly, reporters don't bother to know what MSIV - Main Steam Isolation Valve - is. They don't seem curious either to ask questions like:

How did the expansion joint get damaged?
Was it by the earthquake?
Was it by pressure that exceeded the spec?
Was it by high heat that exceeded the spec?
If it was high pressure, what caused the high pressure?
If it was high heat, what caused the high heat? What are the implications for other nuclear power plants in Japan (and the world) that use this type of joints for many critical safety components in the plants?

Instead, they'd rather write about "nosebleed" in Fukushima Prefecture and how TEPCO's employees "disobeyed" the order and fled from Fukushima I NPP on March 15, 2011 (that's according to fanciful Asahi Shinbun). (More later, maybe.)

Below are the tweets from "Happy", who was hoping that the leak would be from one of the auxiliary pipes that comes through the Containment Vessel, such as the drain pipe:

https://twitter.com/Happy11311/status/466915608441790464 3号機のMSIV室の漏洩は、やっぱりドレンじゃなくてベロー部からだったでし。PCV漏洩止水にスポットがあたってるけどオイラは、これが地震による配管破断だとしたらとても大きな事で、全国の原発再稼働に待ったをかけるべきなんだけど…。

The leak in the Reactor 3 MSIV Room was from the bellows [expansion joint], not from the drain pipe. A focus is on how to stop the leak from PCV (Primary Containment Vessel), but I think it's a serious stuff if this is a rupture of the pipe because of the earthquake, and the restart of nuclear power plants in Japan should be halted...

https://twitter.com/Happy11311/status/466925690588123137 3号機MSIVのベロー部漏洩が地震による配管破断だとしたら、何故大きな問題になるかと言うと、この伸縮継手は重要な配管やPCVやRPVベッセル等々、至る所で使われているタイプで国内全ての原発が同じタイプを使ってると言っても過言じゃないんだ。

The reason why it is a big problem if the leak from the bellows in the Reactor 3 MSIV Room was from the rupture of the pipe caused by the earthquake is because this type of expansion joints are used everywhere on important pipes, PVCs, and RPVs (Reactor Pressure Vessels), etc. It's no exaggeration to say that every single nuclear power plant in Japan uses the same type of expansion joints.

https://twitter.com/Happy11311/status/466925830493335552 ベロー部(伸縮継手)の基本設計は、どちらかと言うと耐震性より熱による配管の伸縮吸収を考慮した設計だから今回、もし地震の影響だとしたら基本設計を見直さないとダメなはずなんだよね。原発ムラが一番怖れてるのが、この地震による配管破断なんだ。

The basic design of a bellows (expansion joint) takes into account the expansion and contraction of the pipe by the heat, rather than the seismic resistant capacity. If [the damage] is from the effect of the earthquake, the design would need to be revised. What the "nuclear village" is most afraid of is the rupture of pipes due to an earthquake.

https://twitter.com/Happy11311/status/466926728271515650 だから未だに現場検証も線量が高い理由で実施しないんだと思うんだけどね。これはオイラの予想だけど、たぶん国や東電が考えて出すMSIVの漏洩原因は、｢地震じゃなくて設計圧力以上の圧力がかかった｣とか、｢異常に高い温度熱が原因だった｣とかの発表を数値を出して説明すると思うでし。

That's why I think the on-site investigation hasn't been done, ostensibly due to high radiation. I expect the reason for the MSIV leak that the national government and TEPCO will come up with will be "due to the pressure that exceeded the design pressure, not the earthquake" or "due to extremely high temperature," citing some numbers.

Well, even if they say the damage was due to high pressure or high temperature, I would assume the critical component like this that connects to the super-critical component (MSIV) should not fail in a severe accident that would probably generate high pressure and high temperature that would exceed the design specs.

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#Fukushima I Nuke Plant: Safety Equipment (Rupture Disk) Delayed the Vent, According to TEPCO's Teleconference Video

The Japanese media (members of Japan Press Club) can still view the video of TEPCO's teleconferences in the early days of the nuclear accident that TEPCO was willing to disclose (about 50 hours worth of video), and here's the latest from Tokyo Shinbun.

According to the newspaper, one of the reasons why TEPCO workers couldn't inject water to cool the reactor core, or open the vent line to release the pressure inside the Reactor Pressure Vessels in Reactors 2 and 3 much sooner was because the rupture disks didn't break because the set pressure was too high.

Why was the set pressure too high? Because the Japanese engineers were afraid of radioactive leak from the Primary Containment Vessels and wanted avoid the leak at all costs, says the paper quoting a nuclear researcher.

Much like TEPCO allegedly welded shut the blowout panels in each reactor building at Fukushima I Nuke Plant, except for Reactor 2.

From Tokyo Shinbun (8/29/2012):

福島第一事故　安全装置　ベント妨げる

Safety equipment prevented the vent in the Fukushima I Nuclear Power Plant accident

昨年三月の東京電力福島第一原発事故で、早い段階で原子炉への注水に向け、ベント（排気）をしようとしたのに、配管の途中にある安全装置の設計が悪く、対応が遅れる大きな原因になっていたことが、東電の社内テレビ会議映像から分かった。放射能を閉じ込めるための安全装置が、逆に事故を深刻化させていたことになる。

It was found in the teleconference video of TEPCO that the bad design of the safety equipment installed along the vent pipe delayed the response when they tried to vent in order to inject water into the reactors in the early stage of the Fukushima I Nuclear Power Plant accident in March last year. It can be said that the safety equipment designed to contain radiation ended up worsening the accident.

事故では、２、３号機とも高圧で注水する装置が使えなくなり、消防車などで注水しようとしたが、原子炉（圧力容器）の圧力が高く難航した。

During the accident, the equipment to inject water at a high pressure failed in both Reactor 2 and Reactor 3. TEPCO tried to inject water using fire engines, but had difficulty doing so due to high pressure inside the reactor (Pressure Vessel).

炉の圧力を下げるには、格納容器に蒸気を逃がす弁（ＳＲ弁）を開け、合わせてベントをする必要がある。だが、ベント配管の途中に設置されている「ラプチャーディスク（破裂板）」と呼ばれるステンレスの円板が、ベントの障害となった。

In order to lower the pressure, they needed to open the SR valve to release [the pressure inside the Reactor Pressure Vessel) into the Containment Vessel, and at the same time do the vent. However, the rupture disk - a stainless-steel disk installed in the vent pipe - hindered the vent.

ディスクは、配管にふたをする役目をしており、一定の圧力がかからないと破れない仕組み。誤ってベント弁を開けてしまっても、放射性物質が外部に漏れ出さないようにするのが目的だ。

The rupture disk plugs the pipe, and it is designed not to break unless it is under certain pressure. The purpose is to prevent the leak of radioactive materials when the vent valve is accidentally opened.

しかし、ディスクの設定圧力が高すぎ、早く炉の減圧とベントをして一刻も早く注水をしたいのに、なかなかディスクが破れず対応が遅れ、その間にも核燃料が過熱していく悪循環を起こした。

However, the disk's set pressure was too high, and even when they wanted to lower the reactor pressure and vent so that they could inject water as soon as possible, the disk didn't break, delaying the response and causing the overheating of the nuclear fuel.

テレビ会議の映像には、「ベント前に炉心損傷ということになっちゃう」（十三日午前五時すぎ、３号機への対応で）、「ラプチャーが開くのを待っているところ」（十四日午後十時ごろ、２号機への対応で）など、もどかしい現場の様子が何度も出てくる。

The teleconferencing video shows the frustrated staff at the plant. "Reactor core may be damaged before the vent can be done" (5AM on March 13, regarding Reactor 3), and "We're waiting for the rupture disk to open" (10PM on March 14, regarding Reactor 2).

東電の宮田浩一・原子力安全グループマネジャーは「ベントをしたいと思った時にできなかったことが最もつらい状況だった」と振り返る。

Koichi Miyata, Manager of TEPCO Nuclear Safety Group, reflects, "The hardest time was when we couldn't vent when we wanted to."

経済産業省原子力安全・保安院は事故の反省を踏まえ、ディスクがベントの妨げにならないよう見直すべきだとの考えで、原子力規制委員会に対応を引き継ぐ見通しだ。

As one of the lessons learned from the accident, the Nuclear and Industrial Safety Agency under the Ministry of Economy, Trade and Industry is of the opinion that a revision is necessary so that the rupture disk doesn't get in the way of venting. The agency is to ask the [soon-to-be-created] Nuclear Regulatory Commission to devise countermeasures.

北海道大の奈良林直教授（原子力工学）は「欧州ではディスクを迂回（うかい）するルートを設け割れなくてもベントをできるようにしている国もある。日本はこれまで『格納容器から漏らさない』との呪縛にとらわれており、それが設計にも反映されていた」と話している。

Professor Tadashi Narabayashi of Hokkaido University (nuclear engineering) says, "Some European countries have systems to bypass the rupture disks so that the vent can be carried out even when the rupture disks don't break. So far, Japan has been caught in the trap of "no leak [of radioactive materials] from the Containment Vessel", which is reflected in the design".

According to the report by the Fukushima Accident Independent Investigation Commission set up by the Cabinet Office, the set pressure of the rupture disk was "0.528MPa　abs" for Reactor 2.

The same NISA and Professor Narabayashi (one of the three "Plutonium Brothers") were last heard together in December last year, when NISA officials admitted to the possibility that the very act of venting may have caused the hydrogen explosions in Reactor 1 and Reactor 3.

Further, a Tokyo University researcher (Katsumi Shozugawa) indicated in his paper (link is in Japanese; see the chart in the post) published earlier this year (online in January, published in paper in April) that it may have been the dry vent (= vent directly from the Containment Vessel, without going through the Suppression Chamber) of Reactor 2 on March 15 that released the huge amount of radioactive materials in the surrounding environment, not the explosions of Reactors 1 and 3.

Several days ago, Professor Yukio Hayakawa, speaking in front of a study group of politicians, also said that TEPCO did the vent, and NISA allowed the vent, on March 15, 2011, when it was obvious to them the wind was from the north, blowing toward Tokyo. Professor Hayakawa continued, "Was the vent necessary at that time? I don't know, as I'm not a nuclear engineer. But if the contamination is from the vent, this is a man-made contamination." (Video of the meeting is here, if you understand Japanese.)

To be sure, the wide-area contamination of Kanto region is supposed to have happened on March 20 - 22, 2011, with the rain.　At that time, Reactor 3 building was smouldering, uncontrolled, white smoke then black smoke seen issuing from the wrecked operating floor. But if Reactor 3 building exploded because of the vent, the possibility of which NISA admits, it would be indeed man-made contamination as Hayakawa says.

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#Fukushima I Nuke Plant Reactor 5 Cooling Stopped for 3.5 Hours Due to Ruptured Pipe

A worker doing the routine inspection of the site in the morning of July 3 noticed the seawater gushing from the pipe that connects to one of the two temporary RHRS (residual heat removal system) pumps for the Reactor 5. The rupture on the pipe was 30 centimeters long and 7 centimeters wide.

During the 3.5 hours while the cooling was stopped to replace the pipe, the temperature of the water in the Reactor Pressure Vessel went from 43 degrees Celsius to 48 degrees Celsius, according to Kyodo News Japanese.

So it would take about 40 hours of no cooling till the water inside the RPV starts to boil. (The RPV of the Reactor 5 is at atmospheric pressure.)

TEPCO called it "leakage", just like a "puddle" that turns out to fill the turbine basement or reactor building basement. An understatement.

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#Fukushima I Nuke Plant: Reactor 1 RPV, Reactor 3 Cooling Pipe Broke In the Earthquake, TEPCO Now Says

After two months TEPCO is dribbling the information out which only proves the critics and fringe scholars and the "sensational" media abroad were right from the beginning. First was the news of core meltdowns in all three reactors, and after two months no one cared. Next, the news yesterday that the Containment Vessels, not just the RPV, have holes, and no one cared.

Today, TEPCO admits the Reactor 1's Reactor Pressure Vessel (RPV) may have broken right after the earthquake and the pipe connected to the High Pressure Coolant Injection system (HPCI) for the Reactor 3 probably also broke during the earthquake. (The article linked below doesn't say the piping is for the HPCI, but the earlier Mainichi Japanese article on May 25 says so.)

So much for the "tsunami did it" narrative that's been adopted by the government, TEPCO, and the nuke industry.

And so much for the "reactor will not break" myth cultivated by the nuke industry worldwide.

Still no one cares.

From Mainichi Shinbun English, quoting Kyodo News (5/26/2011):

TOKYO (Kyodo) --The pressure vessel housing nuclear fuel at the No. 1 reactor of the Fukushima No. 1 power plant or its accessory piping is likely to have been partially damaged immediately after the March 11 earthquake, possibly allowing steam to leak out to the containment vessel encasing it, according to data made public by its operator.

At the reactor, the magnitude 9.0 quake registered an intensity smaller than envisaged under its quake-resistance design. But if the temblor actually caused damage to the critical reactor component, power suppliers across the country might be forced to reconsider the quake resistance designs for their reactors.

A diagram showing temperature changes at the reactor's containment vessel indicates that temperatures and pressure momentarily shot up immediately after the quake.

Mitsuhiko Tanaka, a former nuclear reactor design engineer, says high-temperature steam apparently leaked out to the containment vessel after either the reactor's pressure vessel or its accessory piping was partially damaged.

The operator, Tokyo Electric Power Co., admitted Wednesday that critical cooling piping at the same plant's No. 3 reactor may also have been damaged in the quake.

The utility, known as TEPCO, had earlier suggested that no major damage was done to the reactor, such as ruptures in the facility's main steam piping, until the arrival of massive tsunami after the quake.

"If we do our analysis on the premise that there was a leak in the piping, it matches (data) in reality," a TEPCO official said at a news conference, referring to possible damage at the No. 3 reactor. "We can't deny the possibility."

According to TEPCO, as soon as the reactor's emergency core cooling system was activated shortly after noon on March 12, pressure inside both the reactor's pressure vessel and containment vessel, which encases the pressure vessel, dropped, suggesting that steam was leaking from the cooling pipe.

While measuring devices may have malfunctioned, pressure readings corresponded to an analysis based on the hypothesis that steam did indeed leak from the piping, TEPCO said.

At the No. 3 reactor, the earthquake had an intensity greater than envisioned under resistance guidelines. The cooling piping is housed in a building designed to resist direct damage from tsunami.

"We must fully accept the fact that (the earthquake) has been cited as a possible" cause for the damage to piping, said Goshi Hosono, a special adviser to Prime Minister Naoto Kan, at a news conference.

"A thorough investigation should be carried out on the cause of the incident" after the government's Nuclear and Industrial Safety Agency analyzes related data, he added.

Agency spokesman Hidehiko Nishiyama stressed at the same news conference that steam leaks from the piping have not actually been confirmed.

Another analysis by TEPCO has shown that breaches may have occurred to containment vessels encasing the Nos. 1 and 2 reactors at the power plant in Fukushima Prefecture, possibly causing leaks of highly radioactive water.

The possible ruptures to the containment vessels at the Nos. 1 and 2 reactors are certain to complicate efforts to deal with accumulating contaminated water there, raising questions about the soundness of a TEPCO plan to rebuild a stable cooling system by around mid-July.

In a report submitted to the agency, TEPCO said that if a breach around 3 centimeters in diameter occurred at the No. 1 reactor's containment vessel 18 hours after the quake and it widened to about 7 cm 50 hours after the quake, it would account for changes in pressure readings inside the containment vessel.

TEPCO said it believes that parts used to ensure air tightness in the containment vessel may have broken from overheating, judging from temperatures measured when the leaking possibly occurred.

The company also hypothesized that a rupture roughly 10 cm in diameter occurred to the No. 2 reactor's containment vessel 21 hours after the quake due to elevated temperatures, among other factors, finding that it also corresponds with data obtained.

The same TEPCO report has also shown that massive amounts of hydrogen likely formed at the Nos. 1 to 3 reactors shortly after water levels dropped in their reactor cores and exposed nuclear fuel inside, possibly causing explosions at the buildings housing the reactors.

According to TEPCO's analysis, about 750 kilograms of hydrogen gas was produced at the No. 1 reactor, between 350 and 800 kg at the No. 2 reactor and between 600 and 700 kg at the No. 3 reactor.

Hydrogen is formed when zirconium cladding on fuel rods gets heated and reacts chemically with water.

Between 300 and 400 kg of the gas quickly formed within an hour of exposure at each reactor, the analysis shows, though No. 2 was spared the kind of explosion that blew off the roofs of the buildings for the other two reactors in the days following the massive quake and tsunami.

There is a possibility that the No. 2 reactor escaped an explosion because a ventilating hatch on the upper part of its building was opened in time, unlike at the Nos. 1 and 3 reactors.

TEPCO is struggling to bring the three reactors and a spent fuel storage pool at the No. 4 reactor under control, with the plant's two other reactors having already been brought into a stable condition called "cold shutdown."

(PS: Struggling almost all day with the ISP tech support for internet connection at our new place. Still only manage to get onto the net one computer at a time, and this ISP claims they don't know anything about networks with a third-party router (a major one like Linksys). Aghhh.)

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#Contaminated Water Treatment System: TEPCO Will Bypass Clogged Steel Pipes

The system has the low throughput (37 tonnes/hour instead of 50) on top of the low operating rate (53% in the most recent week). So although not 100% sure, TEPCO thinks it's because of steel pipes clogged up with radioactive sludge. So the company is planning to bypass the particular section and see if the throughput increases.

From Jiji Tsushin via Yahoo Japan (7/23/2011):

福島第1原発事故で、東京電力は23日、高濃度の汚染水処理システムの流量が計画の毎時50トンを大幅に下回る37トン程度に減少している問題を解決する ため、内壁にのり状の汚泥が付着して流路が狭くなっている鋼鉄製配管100～200メートル分をルートから外し、ポリ塩化ビニール製ホースの「バイパス」 を設置することを明らかにした。

The contaminated water treatment system at Fukushima I Nuclear Power Plant has been suffering from the lower than designed throughput of 37 tonnes per hour instead of 50. On July 23, TEPCO disclosed a plan to create a 'bypass" using a PVC hose to divert the flow from going through 100 to 200 meters of steel pipes which are clogged with the sludge.

　準備として同日、配管表面の放射線量を測定したところ、毎時50ミリシーベルトと高かったため、作業方法を検討している。　

The company measured the radiation on the surface of the steel pipes in preparation of the work, and the radiation was high at 50 millisieverts/hour. TEPCO is considering how to proceed in the high radiation condition.

I think the PVC hose TEPCO is planning to use is an orange-colored hose that has been used throughout the plant, called "Kanaflex", which had an unfortunate rupture the other day.

Since TEPCO hasn't released the "survey map" (contamination map) of the plant since June 24, I don't know which pipe segment that TEPCO is talking about. The June 24 map shows the surface radiation of the pipes that transfer the contaminated water all exceeds 100 millisieverts/hour and as high as 210 millisieverts/hour.

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