Tepco is removing the fuel assemblies from reactor4 pool. NRA
(Nuclear Regulation Authority) commented the radiation dose in pool area
is too high, they ordered Tepco to take measures to reduce the
radiation level.
Tepco was stating the pool
water shields radiation from the fuel assemblies. However now that the
pool water is highly contaminated, the workers also need to protect
themselves from the increased radiation dose by the pool water.
The workers check inside of the water from above the refueling crane
moving above the water. Tepco put lead plate over the crane to reduce
the radiation level.
http://www.tepco.co.jp/tepconews/library/movie-01j.html
Iori Mochizuki
Showing posts with label fuel rods. Show all posts
Showing posts with label fuel rods. Show all posts
Thursday, February 6, 2014
Friday, January 10, 2014
Removal of nuclear fuel at Fukushima plant resumes after holiday break
January 8, 2014 – FUKUSHIMA, Japan – Work to remove nuclear fuel from a damaged reactor building at the Fukushima No. 1 nuclear power plant was proceeding smoothly as efforts resumed Jan. 6 after the conclusion of the New Year’s holidays. Work initially got under way on Nov. 18 at the storage pool of the damaged No. 4 reactor building to remove 1,533 nuclear fuel assemblies, but was suspended Dec. 22 for the holiday period. Two officials from the Fukushima prefectural government’s safety management division observed the resumption of the removal work for an hour during the afternoon of Jan. 7. The officials observed Tokyo Electric Power Co. workers lifting a nuclear fuel assembly from the storage pool and putting it into a cask. It was the first fuel assembly removed this year and the 133rd to date. TEPCO workers remove the fuel assemblies one at a time and place them in a storage cask that can hold 22 of the assemblies. The cask is then transported by vehicle to a common pool on the premises. TEPCO plans to remove all 1,533 fuel assemblies by December 2014. The prefectural safety management division said it plans to conduct its next observation of the operation as soon as possible. -AJW
http://theextinctionprotocol.wordpress.com/2014/01/08/removal-of-nuclear-fuel-at-fukushima-plant-resumes-after-holiday-break/
Friday, January 3, 2014
Wednesday, January 1, 2014
#Fukushima I NPP Reactor 3: Debris Removal from Spent Fuel Pool Has Started
There were a few news outlets in late November and early December last year that reported TEPCO would start removing the debris from the Reactor 3 Spent Fuel Pool at Fukushima I Nuclear Power Plant in mid December. Hardly anyone paid attention. (No one probably thought it was possible.) Then there was no news of it actually starting.Well, news or not, the work started on December 17, 2013. That information was shared at the meeting on December 26, 2013 on "Roadmap to Decommissioning", which was available via live feed on the net. However, unless you are one of the dwindling number of reporters and net citizens who continue to follow the accident by attending/watching such meetings, you wouldn't know.
I didn't know because I couldn't watch the whole meeting and didn't take a look at the entire document that contained the information until now.
There is no photos or videos posted at TEPCO's site (in the Photos and Videos Library).
From the 242-page document presented at the December 26, 2013 meeting of "Roadmap to Decommissioning" (pages 152-158):
In order to remove fuel assemblies from the Reactor 3 Spent Fuel Pool, removal of large-size debris in the Spent Fuel Pool started (December 17).Enlarged images:
Reinforcing bars and deck plates that won't interfere with the Fuel Handling Machine [number 8 in the 3-D model] will be removed by the first half of February 2014.
The incident that caused the video camera to drop into the pool has been investigated and the countermeasures put in place.
The order of large-size debris removal:
0. Measures to prevent [additional] debris from falling into the pool (by covering with liners)
1. Remove reinforcing bars, deck plates (1->2->3) - Current work
2. Remove masts, trusses (4, 5, 6, 7)
3. Remove the Fuel Handling Machine (8)
4. Remove the end-track on the west side of the Fuel Handling Machine (4)
5. Remove debris from the cask area (10)
3-D debris map from a different angle, and the location of the video camera that dropped into the pool in November last year:
Kyodo also reports that two cranes will be used, and up to 11 monitoring cameras will be used. All the work will be done by remote-controlled vehicles and equipment. No information whether the human workers are to be posted near the work for further safety monitoring.
All of the MOX fuel that TEPCO had at the plant was in the reactor itself at the time of the accident.
Tuesday, December 3, 2013
Tepco Adviser: Fuel is damaged in two Fukushima pools — 150 billion Bq/m³ of Cesium-137 at Unit 3, possible second explosion after 3/11 — “Certainly appears something of significance occurred”
Jiji Press, Nov. 28, 2013: [Tepco] plans to begin work next month at the earliest to remove large chunks of rubble from a spent fuel pool in the No. 3 reactor building, according to officials.
Nuclear Energy Agency, April 2013: Interim and long term roadmap until decommissioning for unit 1 to unit 4 of Fukusahima Daiichi NPS [...] 2013-2020: Study of treatment methods of damaged fuel removed from spent fuel pool
Congressional Briefing Update by Lake Barrett (Now advising Tepco on Fukushima crisis), July 29, 2011: Units 2 & 3 Pools Have Some Damaged Fuel [...] Building Debris In Unit 3 Pool [...] Cesium 137 Levels in 150,000 Bq/ml (150,000,000,000 Bq/m³) [...] Al Rack Corrosion [...] Adding Boric Acid
Testimony of Lake Barrett (Now advising Tepco on Fukushima crisis), U.S. House of Representatives, May 13, 2011: Although information is very sketchy, it seems based on water samples taken, there has been damage to spent fuel that is stored in the Units 2 and 3 spent fuel pools. Information as to what happened in these pools is still unavailable, so it is impossible to determine the significance at this time, but it certainly appears that something of significance occurred.
Report to Science Panel (U.S. Congress) by Lake Barrett (Now advising Tepco on Fukushima crisis), March 19, 2011: [...] I was writing my summary of the situation, then I could not reconcile conflicting data. The more I dug into the available information the more confusing and contradictory it was. In my putting the pieces together, I discovered that there had been several unreported major explosions in Unit 4 that had happened and also an apparent unreported loss of water in the Unit 3 spent fuel pool. [...] It is possible that [Unit 3's] pool may have overheated resulting in a second explosion here also.
Monday, November 25, 2013
Fukushima reactor cores (1,2, & 3) may have had “Melt Through to China Syndrome” and went into the earth itself — Includes over 1,500 pounds of plutonium
[...] It is becoming apparent that the three molten cores, each weighing 120 to 130 tons have not only melted their way through 6 inches of steel in the reactor vessels, but they now either sit on concrete floors of the severely cracked containment buildings or they have melted their way into the earth itself – this, in nuclear parlance, is called ‘A Melt Through to China Syndrome’.http://enenews.com/fukushima-reactor-cores-melt-china-syndrome-gone-earth-1500-pounds-plutonium
[...] Each reactor core contains 500lbs of plutonium, but Reactor 3 contains even more, because it also contained plutonium/uranium fuel rods which were placed inside the core as an experiment.
[...] The whole reactor site sits on sodden ground, which has now become unstable, muddy and possibly liquefied. The site itself experiences many minor earthquakes each day, but should a quake greater than 6 or 7 on the Richter scale occur, it is likely that one or several of the buildings could collapse with absolutely disastrous consequences. [...]
Scientist back from Japan: Melt-through of Fukushima containment vessels being discussed — They can’t locate any of the 3 molten reactor cores — “It’s bad, it’s definitely not over”
Cape Cod Times, Nov. 24, 2013: [Woods Hole Oceanographic Institution Senior Scientist Ken] Buesseler, along with a team from WHOI, made the first of his three visits to the Fukushima area in June 2011 [...] the Japanese are not able to locate three molten reactor cores. There is ongoing discussion of whether the cores have undergone a meltdown or a melt-through of the containment vessels, Buesseler said. “You can’t send humans in there. It takes decades to come up with a plan,” he said. “It’s bad. It’s definitely not over yet.”Asia Times, Nov. 18, 2013: At least some of the reactor cores are believed to have melted through the containment vessels, and possibly into the ground, contaminating groundwater with unprecedented levels of hot particles.
Kyodo, Nov. 20, 2013: The Nos. 5 and 6 reactors [...] will not actually be dismantled and instead will be used as a research facility to develop technologies for achieving the unprecedented task of removing melted fuel from the Nos. 1 to 3 crippled reactors [...]
NPR, Nov. 18, 2013: [...] And then there are the three reactors that melted down, which will pose an even greater challenge. “They have fuel not just in the pools above the reactors, but in the cores themselves. That fuel is melted down and it’s going to take a very, very long time to even figure out how to get that fuel out,” [NPR's Geoff Brumfiel] says.
More from Buesseler: NHK: There was a melt-through so Fukushima fuel is definitely down with the groundwater, and that's flowing into Pacific -- Americans need to watch, it gets international very quickly -- May already be at West Coast -- No 'immediate' risk (VIDEO)
http://enenews.com/scientist-back-from-japan-they-cant-locate-any-of-the-molten-reactor-cores-melt-through-of-containment-vessels-being-discussed-its-bad-its-definitely-not-over-yet-at-fukushima
Sunday, November 24, 2013
Revered California Physician: The problem we face at Fukushima is absolutely huge — I may leave West Coast during attempt to remove nuclear fuel (VIDEO)
The Santa Barbara Independent, Nov. 7, 2013: Doctor Talks Dangers of Fukushima Fallout; Stephen Hosea Expounds on the Problems with Nuclear Power [...] The Santa Barbara physician discussed the dangers of nuclear power plants at a lunchtime conference packed with health-care professionals at Cottage Hospital [...]
Dr. Hosea’s background is discussed in this Santa Barbara News-Press article: “He is just a phenomenal doctor, as well as just a wonderful guy,” said Dr. Elliot Schulman, health officer and Santa Barbara County Public Health director. “Everyone concurs,” said Peter MacDougall, past president of the Cottage Hospital board of directors. “Not only does he have tremendously strong technical competencies, but his personal modalities with patients, his caring, the deep sensitivity he shows represent just a terrific model for new doctors.” “He’s as close to a model physician as you could ask for,” Mr. MacDougall said. “We are, frankly, blessed to have a man of his talents.” [...] Government officials consider him a go-to guy, regularly seeking his advice [...]
“The Perils of Fukushima: What You Don’t Know Really Could Kill You”, Dr. Stephen Hosea, Published Nov. 23, 2013:
At 30:45 in
Should an event occur [during attempt to remove fuel from Unit 4], all of the radioactivity is going to go straight up into the air. We saw where it went the last time that that occurred. This is happening in the next two weeks. This is a possibility that could happen to each and every one of us. And I can tell you, it wasn’t until I started looking into this that I realized this was a possibility to happen. I certainly haven’t taken any preparations for this. I’m not exactly sure what the preparations are, but I think we ought to know so we can at least take whatever preparations we want to take. I may have to make a visit back to Boston during this period of time to protect myself from this.
At 37:15 in
In summary, radioactive water continues to leak into the Pacific Ocean. Radioactive materials at Fukushima are in an unstable, potentially explosive situation. The potential effect on the water we drink, the air we breathe, and the food we eat are at best speculative. Immediate information and action are necessary as soon as possible. [...] The problem we face at Fukushima is absolutely huge.
Source: First try to remove spent fuel from Unit 4 could be next week — Nuclear Engineer: Everyone’s nervous about pulling out used rods that are corroding; Will zircoloy tubes break and spill fuel pellets, leading to a criticality? (AUDIO)
Kyodo News, Nov. 23, 2013: Work to remove used fuel at Fukushima No. 4 spent fuel pool eyed Tues. [...] Work to remove spent fuel from a storage pool inside a damaged reactor building at the Fukushima Daiichi nuclear complex will begin on Tuesday at the earliest, a source close to the operator of the Fukushima plant said Saturday. [...]
Chris Harris, former licensed Senior Reactor Operator and engineer, Nov. 21, 2013 (at 30:15 in): [I spoke with some colleagues this week and they're] concerned about a criticality event. […] Of course I asked them about the boraflex, which is the boronated rubber — again a nervous laugh. They said that’s all gone, you’ve got to consider that gone also. That’s pretty much the consensus of everyone there, including one of the fellows that actually goes to Fukushima. So I got some inside information on that too.
Harris (at 45:30 in): The corrosion that’s occurring because of the seawater, everyone is rather nervous about the corrosion that’s happening and how much material is being lost, mainly from the zircoloy tubing that houses the fuel pellets themselves. They don’t know the actual wastage, and of course the structural integrity — so when you go ahead and start pulling the fuel, is there going to be a loss of the pellets? […] You could get a criticality event.
Tuesday, November 19, 2013
Damaged Japan Fukushima plant begins removing fuel rods
November 19, 2013 – JAPAN – Workers started removing radioactive fuel rods Monday from a reactor building at the crippled Fukushima Dai-Ichi nuclear power plant, Tokyo Electric Power Co. said. The painstaking and risky task is a crucial first step toward a full cleanup of the earthquake and tsunami-damaged plant in northeastern Japan. The Unit 4 reactor was offline at the time of the March 2011 disaster, and its core didn’t melt as Units 1-3 did. But hydrogen explosions blew the roof and walls off the Unit 4 building and weakened the structure, leaving it vulnerable to earthquakes. Tokyo Electric, known as TEPCO, has since reinforced the building, but experts say keeping so many fuel rods in a storage pool in the building still poses a major safety risk. “The operation is an important step toward decommissioning Fukushima Dai-ichi, which would take 30-40 years,” TEPCO President Naomi Hirose said in a video message on the company’s website. TEPCO has built a massive steel structure next to and partly over Unit 4 to mount cranes for the operation. It will take at least until the end of 2014 to finish moving the 1,533 sets of fuel rods, including 202 unused sets, to a safer location. Each set includes about 60-80 fuel rods containing uranium-based fuel pellets.
TEPCO will remove the unused fuel rods first, and will then move on to the more radioactive spent fuel. At the very end it will remove three sets of rods that are slightly damaged. The storage pools in Units 1-4 contain a total of 80 sets of rods with slight damage, most of which occurred years ago. TEPCO spokesman Noriyuki Imaizumi said a group of six workers safely stored four sets of fuel rods in a cask on Monday. No problems were reported. The operation is delicate. Experts say the fuel rod sets may have been damaged or jammed by small pieces of debris that fell into the pool during the explosions. Some have also raised concern about a major earthquake hitting during the removal work. Two other reactors, Units 5 and 6, were also offline at the time of the disaster and eventually went into normal shutdown. They are also expected to be decommissioned. – ABC News
http://theextinctionprotocol.wordpress.com/2013/11/19/damaged-japan-fukushima-plant-begins-removing-fuel-rods/
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