Japan's turn

[Smurf1976]

• Odds of meltdown resulting in nasty radiation spew: 0.01%.

• 
  In view of the consequences of such an event, those odds are still disturbingly high.
  
  We're talking about a massive impact on the environment and human life here. It's not as though it's something comparatively trivial like a cruise ship sinking, oil spill or collapse of a city building.
  
  The odds may well be low, but the consequences are huge and that's the problem.

 

[skc]

• Odds of meltdown resulting in nasty radiation spew: 0.01%.
• Odds the situation slowly calms down from here on in, with relatively minor radiation issues: 99.9%.
  [*]Odds of something else unforeseen: 0.01%.
• Odds of the media needing to beat up the story 100%

Or the media is full of **** and have a need to report negatives.

I bet you didn't see this coming!

UFOs At Fukushima Reactor Tragedy? HD
http://www.youtube.com/watch?v=Sr5IV4kWMwU

 

[poverty]

I bet you didn't see this coming!

UFOs At Fukushima Reactor Tragedy? HD
http://www.youtube.com/watch?v=Sr5IV4kWMwU

I WANT TO BELIEVE

 

[Agentm]

Fukushima nuclear accident: Saturday 19 March summary

Posted on 20 March 2011 by Barry Brook


Last Saturday the the crisis level at the Fukushima Daiichi nuclear power station was rapidly on the rise. Hydrogen explosions, cracks in the wetwell torus and fires in a shutdown unit’s building ”” it seemed the sequence of new problems would never end. A week later, the situation remains troubling, but, over the last few days, it has not got any worse. Indeed, one could make a reasonable argument that it’s actually got better.
Yes, the IAEA has now formally listed the overall accident at an INES level 5 (see here for a description of the scales), up from the original estimate of 4. This is right and proper ”” but it doesn’t mean the situation has escalated further, as some have inferred. Here is a summary of the main site activities for today, followed by the latest JAIF and FEPC reports. You also might be interested in the following site map:

Another large cohort of 100 Tokyo fire fighters joined the spraying operation to cool down the reactors and keep the water in the spent fuel ponds. The ‘Hyper Rescue’ team have set up a special vehicle for firing a water cannon from 22 m high (in combination with a super pump truck), and today have been targeting the SNF pond in unit 3. About 60 tons of sea water successfully penetrated the building in the vicinity of the pool, at a flow rate of 3,000 litres per minute. Spraying with standard unmanned vehicles was also undertaken for 7 hours into other parts of the the unit 3 building (delivering more than 1,200 tons), to keep the general containment area cool. The temperature around the fuel rods is now reported by TEPCO (via NHK news) to be below 100C.


Conditions in unit 3 are stabilising but will need attention for many days to come. Promisingly, TEPCO has now connected AC cables to the unit 1 and 2 reactor buildings, with hopes that powered systems can be restored to these building by as early as tomorrow (including, it is hoped, the AC core cooling systems), once various safety and equipment condition checks are made.


Holes were made in the secondary containment buildings of Units 5 and 6 as a precautionary measure, to vent any hydrogen that might accumulate and so prevent explosions in these otherwise undamaged structures. The residual heat removal system for these units has now been brought back on line and these pools maintain a tolerable steady temperature of 60C. More here. These buildings were operating on a single emergency diesel generator, but now have a second electricity supply via the external AC power cable.
Why are they concentrating on these activities? Let’s revisit a bit of the history of last week. The spent fuel pool still has decay heat (probably of the order of few MW in each pool) that requires active cooling. When power went out on Friday, the cooling stopped and the pool temperature has been rising slowly over the weekend, and probably started boiling off (and a large volume may have also been lost due to ‘sloshing’ during the seismic event). The pool is located on the 4th floor above the reactor vessel level. It remains unclear why they could not arrange fire trucks to deliver the sea water before the fuel rods got damaged and started releasing radioactivity. Now the effort is hampered by the high radiation level (primarily penetrating gamma rays). This is the inventory of those spent fuel ponds that have been causing so many headaches:

In order to remove the decay heat after the reactor shutdown, the cooling system should be operating. Following the loss of offsite power, the on-site diesel generators came on but the tsunami arrived an hour or so later and wiped out the diesel generators. Then the battery provided the power for 8 hours or so, during which time they brought in portable generators. However, the connectors were incompatible. As the steam pressure built up inside the pressure vessel, the relief valve was open and dumped the steam to the pressure suppression chamber, which in turn was filtered out to the confinement building and the hydrogen explosion took out the slabs.

The sea water was then pumped in by fire trucks and the reactor pressure vessels are now cooled down to near atmospheric pressure but the fuel assemblies are uncovered at the top quarter or third (the FEPC updates give the actual pressure and water levels). It appears that the pressure vessels and the reactor containment structures are intact, except the Unit 2, where the hydrogen explosion took place inside the containment and hence damaging the lower wetwell torus structure (but almost certainly not the reactor vessel, although the exact status is unclear). It appears that the radioactivity releases are mostly coming from the spent fuel storages than the reactor cores.

World Nuclear News has a really excellent extended article here entitled “Insight to Fukushima engineering challenges“. Read it! Further, you must watch this 8 minute reconstruction of the timeline of the accident done by NHK ”” brilliant, and really highlights the enormous stresses this poor station faced against a record-breaking force of nature. As I’d noted earlier, just about everything that could have went wrong, did. But valuable lessons must also be learned.

 

[Agentm]

The IAEA and Japanese government has reported the potential contamination of food products from the local Fukushima area via radioactive iodine (mostly vented as part of the pressure relief operations of units 1 to 3). This is a short-term risk due to the 8-day half-life of radioactive iodine (and a small risk, given the trace amounts recorded), but precautions are warranted, as discussed here. What does this mean?

In the case of the milk samples, even if consumed for one year, the radiation dose would be equivalent to that a person would receive in a single CT scan. The levels found in the spinach were much lower, equivalent to one-fifth of a single CT scan.
​

… and to further put this in context:

The UK government’s chief independent scientific advisor has told the British Embassy in Tokyo that radiation fears from the stricken Fukushima nuclear power plant are a “sideshow” compared with the general devastation caused by the massive earthquake and tsunami that struck on 11 March. Speaking from London in a teleconference on 15 March to the embassy, chief scientific officer John Beddington said that the only people likely to receive doses of radiation that could damage their health are the on-site workers at the Fukushima Daiichi plant. He said that the general population outside of the 20 kilometre evacuation zone should not be concerned about contamination.
​

As to the possibility of a zirconium fire in the SNF ponds, this seems unlikely. Zr has a very high combustion point, as illustrated in video produced by UC Berkeley nuclear engineers. They applied a blowtorch to a zirconium rod and it did not catch on fire. The demonstration is shown about 50 seconds into this video. The temperature was said to reach 2000C [incidentally, I visited that lab last year!].​

The the Japan Atomic Industrial Forum has provided their 12th reactor-by-reactor status update (16:00 March 19).​

Here is the latest FEPC status report:
””””””””””””””-

• Radiation Levels
  • At 7:30PM on March 18, radiation level outside main office building (approximately 1,640 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 3,699 micro Sv/h.
  • Measurement results of ambient dose rate around Fukushima Nuclear Power Station at 4:00PM and 7:00PM on March 18 are shown in the attached two PDF files respectively.
  • At 1:00PM on March 18, MEXT decided to carry out thorough radiation monitoring nationwide.
  • For comparison, a human receives 2,400 micro Sv per year from natural radiation in the form of sunlight, radon, and other sources. One chest CT scan generates 6,900 micro Sv per scan.
• Fukushima Daiichi Unit 1 reactor
  • Since 10:30AM on March 14, the pressure within the primary containment vessel cannot be measured.
  • At 4:00PM on March 18, pressure inside the reactor core: 0.191MPa.
  • At 4:00PM on March 18, water level inside the reactor core: 1.7 meters below the top of the fuel rods.
  • As of 3:00PM on March 18, the injection of seawater continues into the reactor core.
  • Activities for connecting the commercial electricity grid are underway.
• Fukushima Daiichi Unit 2 reactor
  • At 4:00PM on March 18, pressure inside the primary containment vessel: 0.139MPaabs.
  • At 4:00PM on March 18, pressure inside the reactor core: -0.002MPa.
  • At 4:00PM on March 18, water level inside the reactor core: 1.4 meters below the top of the fuel rods.
  • As of 3:00PM on March 18, the injection of seawater continues into the reactor core.
  • Activities for connecting the commercial electricity grid are underway.
• Fukushima Daiichi Unit 3 reactor
  • At 2:00PM on March 18, six Self Defense emergency fire vehicles began to shoot water aimed at the spent fuel pool, until 2:38PM (39 tones of water in total).
  • At 2:42PM on March 18, TEPCO began to shoot water aimed at the spent fuel pool, until 2:45PM, by one US Army high pressure water cannon.
  • At 3:55PM on March 18, pressure inside the primary containment vessel: 0.160MPaabs.
  • At 3:55PM on March 18, pressure inside the reactor core: -0.016MPa.
  • At 3:55PM on March 18, water level inside the reactor core: 2.0 meters below the top of the fuel rods.
  • As of 3:00PM on March 18, the injection of seawater continues into the reactor core.
• Fukushima Daiichi Unit 4 reactor
  • No official updates to the information in our March 18 update have been provided.
• Fukushima Daiichi Unit 5 reactor
  • At 4:00PM on March 18, the temperature of the spent fuel pool was measured at 152.4 degrees Fahrenheit.
• Fukushima Daiichi Unit 6 reactor
  • At 4:00PM on March 18, the temperature of the spent fuel pool was measured at 148.1 degrees Fahrenheit.
• Fukushima Daiichi Common Spent Fuel Pool
  • At 10:00AM on March 18, it was confirmed that water level in the pool was secured.
• Fukushima Daiichi Dry Cask Storage Building
  • At 10:00AM on March 18, it was confirmed that there was no damage by visual checking of external appearance.

At 5:50PM on March 18, Japanese Safety Authority (NISA: Nuclear and Industrial Safety Agency) announced provisional INES (International Nuclear and Radiological Event Scale) rating to the incidents due to the earthquake.
Fukushima Daiichi Unit 1, 2 and 3 Unit = 5 (Accident with wider consequences)
Fukushima Daiichi Unit 4 = 3 (Serious incident)
Fukushima Daini Unit 1, 2 and 4 Unit = 3 (Serious incident)
(No official provisional rating for Fukushima Daini Unit 3 has been provided.)

 

[Agentm]

Fukushima Nuclear Accident – Monday 21 March update

Posted on 21 March 2011 by Barry Brook

It’s not yet time for the period of reflection and introspection on the Fukushima Daiichi crisis, but we’re getting there. Even the U.S. says the worst seems to be over. The IAEA and World Nuclear News have both released new updates on the situation (the IAEA report being particularly comprehensive this time, unlike some of their earlier sparse prose). Steve Darden at Seeker Blog has done an excellent job at extracting the key snippets of information, and so I reproduce his efforts below:
Offsite grid power has been brought to the Daiichi site, and is in the process of connection to each reactors equipment.

Restoration of Grid
Progress has been achieved in restoring external power to the nuclear power plant, although it remains uncertain when full power will be available to all reactors. Off-site electrical power has been connected to an auxiliary transformer and distribution panels at Unit 2. Work continues toward energizing specific equipment within Unit 2.
​

Here’s an excerpt on radiation measurements:

Radiation levels near Fukushima Daiichi and beyond have elevated since the reactor damage began. However, dose rates in Tokyo and other areas outside the 30-kilometre zone remain below levels which would require any protective action. In other words they are not dangerous to human health.
​

At the MIT Nuclear Science and Engineering site, the 20 March status update is encouraging. Included in the report was a note on the actual tsunami heights at the reactor sites:

The Fukushima power plants were required by regulators to withstand a certain height of tsunami. At the Daiichi plant the design basis was 5.7 metres and at Daini this was 5.2 metres.
Tepco has now released tentative assessments of the scale of the tsunami putting it at over 10 metres at Daiichi and over 12 metres at Dainii.
​

In the associated WNN report, is the following IAEA graph of unit 5, 6 fuel pond temperatures.

At units 1 and 2, external power has been restored. Tokyo Electric Power Company (Tepco) said it would restore functions in the central control room shared by the units so that accurate readings could again be taken from the reactor system. Next, workers will check the condition of the water supply systems to the reactor and the used fuel pond. With luck these will be able to go back into operation as they had been immediately after the earthquake on 11 March.
External power for units 3 and 4 should be in place ‘in a few days’ time’, said Tepco.
(…) Despite contradictory comments by the US Nuclear Regulatory Commission to US politicians and media, most observers in nuclear industry and regulation consider the measures taken by Japanese authorities to be prudent and appropriate.
​

 

[Agentm]

Some other points, from NHK news reports:
・TEPCO planned an operation to release air containing radioactive nuclidesinside the containment vessel at unit-3, give a situation of pressure increaseinside the containment in this morning . However, TEPCO decided not to releaseit since the pressure becomes stable later.
・Ministry of Defense performed activity of measuring surface temperature ateach of unit 1,2,3 and 4 from the sky using Helicopter to evaluate the effect ofthe operation of filling the pool with water from the ground today and yesterday.Ministry of Defense expressed the opinion that surface temperature of each unitseems to be 100 degree Celsius or below.
Some other interesting reads from the last day or two:

1. Dan Yurman from Idaho Samizdat reviews the last weeks’ events, and asks some pointed questions about NRC Head Jaczko’s sources of information:

What remains to be known is how much distrust and incomplete information played a role in what has turned out to look like a decision that didn’t have to be made in time for a congressional hearing. Yes, that’s hindsight, but these questions deserve answers and soon.
​

2. Rod Adams from Atomic Insights has a lot more details on the possibility (or lack thereof) of a zirconium fire in the spent fuel ponds. His bottom line:

Despite all previous word, a fire in any used fuel pool is a fantasy that will only occur in a simplified model. It is not a concern in the real world of water, metal and ceramics. (Note: I struggled with whether or not I should waffle and couch that statement with “in my opinion”, but decided against it. Please feel free to conduct experiments that would prove me wrong.)
​

3. Charles Barton from Nuclear Green looks at some lessons from Daiichi:

If the Dai-ichi crisis fails to teach us the importance of moving forward on the implementation of a more advanced and safer nuclear technology, it would be a tragedy.
​

In the coming weeks, I will also be dissecting this new lesson of history on BraveNewClimate. But I want to wait a little longer yet ”” at least until all those units are in cold shutdown and the spent fuel pools are lukewarm once again!
The the Japan Atomic Industrial Forum has provided their 19th reactor-by-reactor status update (10:00 March 21):

Finally, here is the latest FEPC status report:​

””””””””””””””-

• Radiation Levels
  • At 07:00PM (JST) on March 20, radiation level outside main office building (approximately 1,640 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 2,623 micro Sv/hour.
  • Measurement results of ambient dose rate around Fukushima Nuclear Power Station announced at 4:00PM and 7:00PM on March 20 are shown in the attached two PDF files respectively.
  • For comparison, a human receives 2,400 micro Sv per year from natural radiation in the form of sunlight, radon, and other sources. One chest CT scan generates 6,900 micro Sv per scan.
• Fukushima Daiichi Unit 1 reactor
  • At 3:00PM on March 20, pressure inside the reactor core: 0.187MPa.
  • At 3:00PM on March 20, water level inside the reactor core: 1.7 meters below the top of the fuel rods.
  • At 3:00PM on March 20, pressure inside the primary containment vessel: 0.17MPaabs.
  • As of 6:00PM on March 20, the injection of seawater continues into the reactor core.
  • As of 7:00PM on March 20, activities for recovering the external power supply are underway.
• Fukushima Daiichi Unit 2 reactor
  • At 3:00PM on March 20, pressure inside the reactor core: -0.016MPa.
  • At 3:00PM on March 20, water level inside the reactor core: 1.4 meters below the top of the fuel rods.
  • At 3:00PM on March 20, pressure inside the primary containment vessel: 0.125MPaabs.
  • At 3:05PM on March 20, injection of seawater into the spent fuel storage pool has begun, until 5:20PM (total about 40 tons)
  • As of 3:46PM on March 20, the distribution board began to receive the external power.
  • As of 6:00PM on March 20, the injection of seawater continues into the reactor core.
• Fukushima Daiichi Unit 3 reactor
  • At 4:00PM on March 20, pressure inside the reactor core: 0.119MPa.
  • At 4:00PM on March 20, water level inside the reactor core: 1.65 meters below the top of the fuel rods.
  • At 4:00PM on March 20, pressure inside the primary containment vessel: 0.290MPaabs.
  • As of 6:00PM on March 20, the injection of seawater continues into the reactor core.
  • As of 7:00PM on March 20, about 2,605 tons of water in total has been shot to the spent fuel storage pool.
  • As of 7:00PM on March 20, activities for recovering the external power supply are underway.
• Fukushima Daiichi Unit 4 reactor
  • At 8:20AM on March 20, 10 Self Defense Force vehicles began to shoot water aimed at the spent fuel pool, until 9:29AM.
  • As of 7:00PM on March 20, about 83 tons of water in total has been shot to the spent fuel storage pool.
  • As of 7:00PM on March 20, activities for recovering the external power supply are underway.
• Fukushima Daiichi Unit 5 reactor
  • At 2:30PM on March 20: cold shutdown
  • At 4:00PM on March 20, the temperature of the spent fuel pool was measured at 95.2 degrees Fahrenheit.
• Fukushima Daiichi Unit 6 reactor
  • At 10:14PM on March 19, ump for Residual Heat Removal (RHR) started up and cooling of spent fuel storage pool has started.
  • At 4:00PM on March 20, the temperature of the spent fuel pool was measured at 82.4 degrees Fahrenheit.
• Fukushima Daiichi Common Spent Fuel Pool
  • At 09:00AM on March 19, the temperature of the spent fuel pool was measured at 134.6 degrees Fahrenheit.

Our official sources are:

• Office of The Prime Minister of Japan
• Nuclear and Industrial Safety Agency (NISA)
• Tokyo Electric Power Company (TEPCO) Press Releases
• Ministry of Education, Culture, Sports, Science and Technology (MEXT)

 

[Agentm]

and the most thought provoking

coming our way, and this one will spread global..

a little taste of fukushima to enter our healthy lungs..

courtesy of japans thirst for cheap electricity.. without rational thought to consequence

we get to ingest and breathe the beautiful caesium as a consequence..

all good we are told.. all good!! lol

 

[Smurf1976]

and the most thought provoking

coming our way, and this one will spread global..

a little taste of fukushima to enter our healthy lungs..

courtesy of japans thirst for cheap electricity..

I can't really comment on where the radioactive materials will end up, but I would dispute absolutely that nuclear power is "cheap".

Cheap in what sense? It is not cheap financially unless you do dodgy accounting (usually done in the industry by writing off the entire capital cost of the power plant, then claiming that the operating costs of the plant are "cheap" compared to the entire construction and operating cost of a non-nuclear alternative).

A few studies were done in Tasmania into the idea by various people during the period early 1970's to late 1990's. They generally concluded that the real financial cost of nuclear would be higher than the cost of other options (local coal, imported coal, oil, victorian gas, hydro, importing electricity, wind) and would be around several times the cost of the cheapest alternatives. Critically, the cost would be well above the level at which the big 3 electro-metallurgical plants, which are huge users of electricity, would become financially unviable.

Whilst the economics would be different for other locations, it has always been very clear that an Australian nuclear plant would be uneconomic compared to brown coal, black coal or natural gas and nothing has really happened to change that. Nuclear power is not cheap. At best, it's cheper than fuel oil - but there aren't many situations where that's the only alternative available.

 

[DB008]

Found this alternative (Thorium - I will post it in the Thorium thread too)

Thorium Remix 2009 - LFTR in 16 Minutes




Article in "The Telegraph" - UK
Safe nuclear does exist, and China is leading the way with thorium

A few weeks before the tsunami struck Fukushima’s uranium reactors and shattered public faith in nuclear power, China revealed that it was launching a rival technology to build a safer, cleaner, and ultimately cheaper network of reactors based on thorium.
This passed unnoticed –except by a small of band of thorium enthusiasts – but it may mark the passage of strategic leadership in energy policy from an inert and status-quo West to a rising technological power willing to break the mould.

If China’s dash for thorium power succeeds, it will vastly alter the global energy landscape and may avert a calamitous conflict over resources as Asia’s industrial revolutions clash head-on with the West’s entrenched consumption.

China’s Academy of Sciences said it had chosen a “thorium-based molten salt reactor system”. The liquid fuel idea was pioneered by US physicists at Oak Ridge National Lab in the 1960s, but the US has long since dropped the ball. Further evidence of Barack `Obama’s “Sputnik moment”, you could say.

Chinese scientists claim that hazardous waste will be a thousand times less than with uranium. The system is inherently less prone to disaster.

...More on the link below....


http://www.telegraph.co.uk/finance/comment/ambroseevans_pritchard/8393984/Safe-nuclear-does-exist-and-China-is-leading-the-way-with-thorium.html#dsq-content

 

[Boggo]

Not looking too good over there on the last update today, scroll down page of link to 01:30 UTC update.

http://www.iaea.org/newscenter/news/tsunamiupdate01.html

 

[Agentm]

Fukushima Daiichi Nuclear Accident – 26 March status

Posted on 26 March 2011 by Barry Brook
This post provides an update to the various situation summaries at Fukushima Daiichi. Please switch to using this post for comments on the latest status reports and news to hand (the old one is now out of date). For general comments on, use the FD Open Thread #2, and for analysis of the event with respect to future lessons for nuclear power, use this post. Full situation summaries from TEPCO, FEPC and JAIF are given at the bottom of this report.
This is a dramatic before and after photo of the Fukushima Daiichi plant. Click on the image to see more b/a images of the earthquake/tsunami damaged Sendai region (controlled with a swipe tool).

Below is a very brief summary of some key events of the last few days, since the previous status report:
1. There has been concern about salt accumulation in reactor vessels 1-3 (as steam evaporates the injected sea water, the salt is left behind, and if concentrations build to beyond the saturation point, it will begin to deposit and potentially insulate the fuel assemblies). However, NEI now reports the following welcome news:

Fresh water is being injected into the reactor pressure vessel at reactor 3 at Fukushima Daiichi nuclear power plant, Japan’s Nuclear and Industrial Safety Agency said.
TEPCO said that radioactive materials discovered at the reactor 3 turbine building possibly came from water from the reactor system, not the spent fuel pool. TEPCO made that statement after collecting samples of contaminated water in the reactor 3 turbine building and conducting a gamma-emitting nuclide analysis of the sample. The reactor pressure and drywell pressure at reactor 3 remained stable on Friday, leading TEPCO to believe that “the reactor pressure vessel is not seriously damaged.
Cooling efforts at Reactor 1 already had switched back to fresh water cooling. Reactor 2 is still being injected with seawater, but is expected to switch to fresh water soon.
​

The temperature at the bottom head of the reactor pressure vessels are now 149 C (unit 1), 104 C (unit 2) and 111 C (unit 3) — detailed data in reports below.
2. TEPCO Workers laying cables in the turbine hall of unit 3 stood in ankle-deep stagnant water and their feet were irradiated with beta rays (~180 mSv dose), with shallow burns, after ignoring their dosiometer warnings. They have since been hospitalised. Details in the reports below. 17 personnel have now received doses of >100 mSv, but none >250 mSv — the dose allowed by authorities in the current situation.
3. Water spraying continues on spent fuel ponds 2, 3 and 4, to ensure the uranium fuel rods remain covered. The temperature in unit 2 pool was recently measured at 52 C (see detailed data below).
4. On radiation: levels around the plant perimeter are relatively low and steadily decreasing. Levels of I-131 in drinking water supplies in Tokyo are now below regulated limits and restrictions have been lifted. The IAEA radiation monitoring data, at a distance of 34 to 62 km from Fukushima Daiichi, showed very low levels. To quote:

On 25th March, the IAEA radiation monitoring team made additional measurements at distances from 34 to 62 km from the Fukushima nuclear power plant. At these locations, the dose rate ranged from 0.73 to 8.8 microsievert per hour. At the same locations, results of beta-gamma contamination measurements ranged from 0.07 to 0.96 Megabecquerel per square metre.
​

5. World Nuclear News provides a new summary: Fukushima Daiichi two weeks on. To quote:

Investigations are now underway into the unexpectedly high level of contamination in the water, particularly as the basement of the turbine building is not a recognised radiation area. One theory is that there is a leak from the reactor circuit, but pressures in the reactor vessel indicate this must be elsewhere in the loop.
Despite this disappointment, steady progress continues to be made on site. Instrumentation is being recovered at units 1, 2 and 4 and lights are on in the control rooms of units 1 and 3. Power connections have reached all the units and checks are underway before normal systems can be re-energised. The shared pond for used fuel pond has now been reconnected.

Here are some interesting photographs from inside the buildings, taken on 23 March by by the Operational Safety Inspector.
6. Geoff Russell (a regular BNC author on food and climate change issues) has a really good piece, reflecting on many of the issues discussed here over the last few weeks. His original title was: Japanese nukes … good news in a bleak landscape.
Some useful technical details are available from NISA Major Parameters 1800 March 25, and the NISA summary conditions report for each reactor (click on the diagram below to access the PDF):

Below is a situation update of the Fukushima Daiichi site, from TEPCO Washington office:
——————————
(1) Result of the investigation on highly radiated workers.
Below are the investigation results of their working environment. Radiation dose rate of surface of the water is approximately 400 mSv/h. Result of gamma-ray nuclide analyses based on sampling of the stagnant water on the basement floor of the turbine building of Unit 1 of Fukushima Dai-ichi Nuclear Power Station. We are assessing radiation dose of 2 worker’s leg skin by beta ray. This incident would be caused because the workers regarded radiation dose of working area as low from survey result of radiation dose on March 23, it was about 0.5 mSv/hr at 5:00 and no major water puddle there. Workers continued working without recognizing change of work environment although their APD were alarming during the work TEPCO has thoroughly instructed its employees and contractor workers to pay attention to the alarm of their APD and evacuate when necessary.

​

 

[Agentm]

Regarding this event, Fukushima Labor Bureau gave TEPCO verbal instructions. After summerising lessons learned and future measures to this event, TEPCO will report related government ministries and agencies to make sure radiation control thoroughly.
(2) High radiation water may come from the unit 3 reactor, not spent fuel pool.
As for the leakage of radioactive materials at Unit 3 turbine building, we assume the water came from the reactor. We collected sample of the contaminated water in the turbine building of Unit 3 and conducted the gamma-emitting nuclide analysis. We confirmed the following nuclides with short half-life.
Nuclides half-life (days) density (bq/cubic centimeter)
Iodine 131 8.06 1.2 x 10E6
Cesium 136 13.16 2.3 x 10E4
Barium 140 12.75 5.2 x 10E4
There are 148 fuel rods with less than one year of cooling period in the spent fuel pool at Unit 3. Those fuel rods were transferred to the spent fuel pool between Jun 23 and 28, 2010 having had more than 200 days of cooling period. Nuclides with short half-life had sufficient time for decay in the spent fuel pool, so it seems possible that the contaminated water in the turbine building is from the reactor.
We do not deny possibility that there might be certain damage to the reactor of Unit 3. Even should that be the case, as plant parameters such as the reactor pressure and D/W pressure is stable , we presume that RPV is not seriously damaged.
We are injecting seawater and from the night of March 25, fresh water into the reactor. The water turns into steam and comes out from the reactor vessel through the SRV, then depressurized at the suppression chamber and condensed to water. This flow of water is cooling the reactor. Having experienced fluctuations of temperature and pressure, the containment function might be loosened somewhere. In any event, the above is a possibility, not yet confirmed.
(3) Water injection into the pools and the reactors.
Unit 1: Sea water injection into the reactor pressure vessel, from 3:37 pm on March 25th, we have started to inject fresh water into it.
Unit 2: From 10:30 am on March 25th, seawater injection through Fuel Pool Cooling and Filtering System (FPC) was started. This finished at 0:19 pm.
Unit 3 From 5:35 am on March 24th, seawater injection through Fuel Pool Cooling and Filtering System (FPC) was started and finished at 4:05 pm.
Spraying at the spent fuel pool by Kawasaki City Fire Department was carried out from 1:28 pm to 4:00 pm on March 25th.
Unit 4: From 2:35 pm on March 24th, spraying water by the concrete pumping vehicle was conducted and ended at approximately 5:30 pm on the same day.
From 6:05 am on March 25th, seawater injection through Fuel Pool Cooling and Filtering System (FPC) was started and finished at 10:20 am.
””””””””””””””””–
Here is the latest FEPC status report:

• Radiation Levels
  • At 7:00PM (JST) on March 25, radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 199.5 micro Sv/hour.
  • Measurement results of environmental radioactivity level around Fukushima Nuclear Power Station announced at 7:00PM on March 25 are shown in the attached PDF file. English version is available at: http://www.mext.go.jp/english/radioactivity_level/detail/1303962.htm
  • For comparison, a human receives 2,400 micro Sv per year from natural radiation in the form of sunlight, radon, and other sources. One chest CT scan generates 6,900 micro Sv per scan.
• Fukushima Daiichi Unit 1 reactor
  • At 11:00AM on March 25, activities for the injection of freshwater in place of seawater into the reactor core started and at 3:37PM, the injection of freshwater into the reactor core started.
  • At 2:00PM on March 25, pressure inside the reactor core: 0.342MPa.
  • At 2:00PM on March 25, water level inside the reactor core: 1.65 meters below the top of the fuel rods.
  • At 2:00PM on March 25, pressure inside the primary containment vessel: 0.280MPaabs.
• Fukushima Daiichi Unit 2 reactor
  • At 10:00AM on March 25, the temperature of the spent fuel pool: 82.4 degrees Fahrenheit.
  • At 10:30AM on March25,　TEPCO began to inject seawater into the spent fuel pool via cooling and purification line, until at 12:19PM (approximately 38 tons in total).
  • At 11:00AM on March 25, activities for the injection of freshwater in place of seawater into the reactor core started.
  • At 2:00PM on March 25, pressure inside the reactor core: -0.016MPa.
  • At 2:00PM on March 25, water level inside the reactor core: 1.4 meters below the top of the fuel rods.
  • At 2:00PM on March 25, pressure inside the primary containment vessel: 0.12MPaabs.
  • As of 7:00PM on March 25, approximately 96 tons of water in total has been injected into the spent fuel storage pool.
  • As of 7:00PM on March 25, external power generation is connected and the functionality of the electric devices is being checked.
  • As of 7:30PM on March 25, the injection of seawater into the reactor core continues.

• Fukushima Daiichi Unit 3 reactor
  • At 11:00AM on March 25, activities for the injection of freshwater in place of seawater into the reactor core started and at 6:02PM, the injection of freshwater into the reactor core started.
  • At 1:28PM on March 25, Kawasaki City Fire Department began to shoot water aimed at the spent fuel pool until 4:00PM (approximately 450 tons in total).
  • At 2:00PM on March 25, pressure inside the reactor core: 0.038MPa.
  • At 2:00PM on March 25, pressure inside the primary containment vessel: 0.1089MPaabs.
  • At 2:10PM on March 25, water level inside the reactor core: 1.9 meters below the top of the fuel rods.
  • As of 7:00PM on March 25, approximately 4,497 tons of water in total has been shot to the spent fuel storage pool.
• Fukushima Daiichi Unit 4 reactor
  • At 6:05AM on March25, TEPCO began to inject seawater into the spent fuel pool via cooling and purification line, until at 10:20APM.
  • At 7:05PM on March 25, TEPCO began to shoot water aimed at the spent fuel pool, with a specialized vehicle normally used for pumping concrete.
  • As of 7:00PM on March 25, approximately 685 tons of water in total has been shot to the spent fuel storage pool.
  • As of 7:00PM on March 25, external power generation is connected and the functionality of the electric devices is being checked.
• Fukushima Daiichi Unit 5 reactor
  • At 3:00PM on March 25, the temperature of the spent fuel pool: 98.4 degrees Fahrenheit.
  • At 3:00PM on March 25, the temperature of the water in the reactor core: 129.0 degrees Fahrenheit.
• Fukushima Daiichi Unit 6 reactor
  • At 3:00PM on March 25, the temperature of the spent fuel pool: 69.8 degrees Fahrenheit.
• Fukushima Daiichi Common Spent Fuel Pool
  • As of 7:00PM on March 25, approximately 130 tons of water in total has been injected to the spent fuel storage pool.

””””””””””””””””””””
Finally, the latest Japan Atomic Industrial Forum summary table (21:00 March 25):

 

[Agentm]

Josef Oehmen and Fukushima – Would I have believed myself?

Posted on 29 March 2011 by Barry Brook
On the 13th of March, I posted an article called “Fukushima Nuclear Accident – A simple and accurate explanation“. This was early on in the Fukushima crisis when people were desperately hungry for understandable information, and yet there were scarce few good explanations available. The post had been written by Dr Josef Oehmen, a research scientist at MIT, in Boston. I’d stumbled across it when it had just been published on Jason Morgan’s new blog, and thought it was worth re-broadcasting, so I contacted Jason and got his and Josef’s permission to reprint.
The rest is history… Via my and Jason’s contacts and through Twitter and the blogs, it soon ‘went viral‘ , and later the Energy Collective reposted my version (with permission) and this amplified its audience even further. A group from MIT then took over management of the information, and did a few further updates, which I also mirrored. To me, it was an example of the internet at its best ”” exponential networking of key information.
However, the story doesn’t end there. It also created a huge amount of indignation, including a flood of vitriolic ad hominem comments on this blog that, if I’d let through the moderation queue, would have made your gentle eyes water! As the situation at Fukushima worsened, the MIT NSE group provided updates that improved upon the original information a little, and also toned down some of the stronger conclusions that had proven overly optimistic (I was also guilty of not fully appreciating the seriousness of the situation caused by the 14 m tsunami at Daiichi Plant). This updating of the information was, apparently, was the most heinous of crimes, and Josef himself was cast as the evil (and grossly unqualified) mastermind at the heart of an international conspiracy! (I was, alas, but a mere pawn in artful machinations…). The story was even taken up by New Scientist, although they got some of the detail (e.g., sequence of events) wrong.
So, what does the fiendish genius ”” with whom I’m since become firm internet buddies ”” have to say on this matter? Should people have listened to him, or should his article have been rightly consigned to ghastly the abyss of HTTP 404 errors? You decide, when you read this guest post…
Oh, and if you’d like to participate in a little 5 minute survey as part of the follow-up research that Josef is doing on this little drama, click here…
Would I have believed myself? On evaluating the quality of reports on topics that one does not know a whole lot about

Guest Post by Josef Oehmen. Josef is a research scientist in mechanical engineering and engineering systems at the Massachusetts Institute of Technology.
On Sunday, March 13, my cousin in Japan posted an email I had written to him on his blog in the early morning at 3am EST. The email explained the context of nuclear physics and engineering, as well as discussed the events at the Daiichi-1 reactor until that point. It also featured my very strong opinion that they are safe. By lunchtime, it was the second most twittered site on the internet (you can read the whole story at http://bit.ly/e1It0T). At the end of the day, it had been translated into more than 9 languages (often multiple times), and after 48 hours had been read by several million people. Two weeks into my unwanted and luckily rapidly cooling off Web 2.0 stardom, I have begun working through the trauma and reflecting. Thanks for sharing, you might think. But one question in particular came up that also has some general relevance:
Would I have believed myself if I came across that blog and had no prior knowledge of nuclear physics and engineering? Or asked another way: How do you judge the quality of TV, radio, print and internet news reporting on topics that you are only superficially familiar with?
Read the answer below. And like everything I write, it is rather lengthy!

Working in an interdisciplinary field as an academic, it is often necessary for me to judge the quality of information from areas outside my core expertise and decide whether they are reliable sources worth studying. Also, when you work with students, you start to develop little antennas when you read to judge if the student really got what she or he is writing about, and ultimately the quality of the students work (although you as the supervisor of course know everything better, well, you might not always be familiar with all the details).
So let’s take the example of my email-turned-blog, imagine I was living in Japan, had no idea about nuclear science and engineering (not too big a stretch someone just said), was looking for some info on Fukushima and came across Jason’s blog. Do I read it? All of it? What do I do then?
My approach to evaluating any sort of reports on the internet (and elsewhere) consists of 5 elements.: 2 regarding trustworthiness, 2 regarding the style (as a measure of effort put into a piece, but also a good indicator of the level of understanding of the author of the subject that he/she write about) and 1 element for content (arguably the most difficult to judge if you are not already familiar with the field). I will have to give myself credit on some of the dimensions, so I am asking you ahead of time for your forgiveness of some literary narcissism in the following.

 

[Agentm]

1. Judging obvious fishiness (Trust)
When you surf the web, you come across a lot of stuff that you can safely disregard immediately. So I have two criteria for an immediate go/no-go decision at the onset:
a. Context: What is the context of the information? Blogs can be places where people put great stuff, but also incredibly stupid things (as I said, just Google my name these days). In the case of Jason’s blog, no points for great existing content, but also no minus points for tons of conspiracy theories and UFO posts. 0 points
b. Hoax potential: Would I have believed the whole story, cousin at MIT writing an email, setting up a blog to share it? Probably yes. Story looks interesting enough at first glance and setting up a blog is little enough work. Testing the opposite hypothesis: Why would anyone go through that much trouble of writing such a long text; invent such a boring cover story; and then assign the authorship to a total nobody in nuclear engineering, and not some expert in the field? So again, nothing major in favor, but also not a deal killer, 0 points.
2. Trustworthiness of the author (Trust)
Again, we have two criteria:
a. Past experience in the field. Is the author an authority in the field? Google clears that one up pretty quickly, certainly not. -1 point.
b. Bias, agenda, background: Checks out, engineering guy, MIT, probably has done his homework. 1 point.
3. Style and presentation (Style)
Is the narrative and style appealing? Again, I usually use this as an indicator of effort and level of understanding on the side of the author. Before I send the original email of to Jason, I scanned it one more time and thought to myself “Hm, this has actually turned into a nice piece of writing.” I probably would have had the same reaction scanning the text – well structured, flowing narrative, clear reasoning. 1 point.
4. Quality of the structure of the work (Style)
Does the article follow a logical structure? The article does seem well structured. It introduces the fundamentals, then progresses to describe what happened in Fukushima so far and drawing on these fundamentals. Seems to make sense. However it is not an academic treatise and strongly opinionated. Still, 1 point.
5. Content quality of the work (Content)
Here, since this is the most important category for me, I use a number of criteria:
a. Are the general fundamentals right? Are general engineering and physics fundamentals right that are used in the writing? Are the terms correctly used? Yes, 1 point.
b. Are specifics right? Are specific fundamental facts (e.g. half-life, types of elements etc.) and specific facts (sizes, amounts, temperatures, events) correct to the extent that I can verify them? Yes, 1 point.
c. Is there an uninterrupted logical flow from context and facts to interpretation? For the most part, yes. There are no logical breaks between the context, the facts being discussed in that context and the conclusions that are drawn. In its own little universe, it makes sense, no conclusions falling out of nowhere, no contradictions. However, again, the writing is not objective and strongly opinionated. But still, 1 point.
d. Are the sources given? Does the article contain sources so I could verify the claims and facts presented by the author? No, not in the narrative, not as footnotes. -1 point.


6. Possible next actions:
So, what should I do with what I just learned from reading the document? If we tally up the points for a first impression, we get 4 out of 10 points. And looking at the critical points, one of them is a biggy: No sources so I could easily verify if what the author claims is true or not. So what to do with it?
a. Disregard. This would mean thinking “oh my god, what a load of junk and a waste of time”. No, that is not what I would have done.
b. Use it to build mental model of the problem and investigate further. This means I use my newly acquired knowledge to build a mental model of the problem. What is the relevant context? What are the critical facts I need to know or monitor? That mental model is then tested (can I confirm what was said about the context, can I confirm what facts were presented?), and once that is done, run with it to grow the context (i.e. integrating understanding of spent fuel ponds) and interpret incoming facts (i.e. how dangerous is the latest venting of steam)?
c. Believe and be done with it. The information I just acquired solves my problem. I believe everything and am done with it (in this case, worrying about Fukushima).
As you can probably tell by the length of discussion of the different points above, I would have gone with b. That concludes my therapeutic reflections. And maybe you find the assessment process useful to make a more conscious choice of the news programs in TV, radio, press and internet you decide to support (I did, and that is why I love Barry and his site bravenewclimate).
Where does that leave us?
1. Help people understand the context. If you help people to understand the context, you help them to help themselves in the future. My hope is that the email made a small contribution to helping the general public, as well as some journalists, in building the context to make a better informed assessment of new facts as they come in. Do your part with your family and friends (as I had originally intended…)
2. Take a stand against mass hysteria. The email I wrote contains both an introduction to some relevant physics and engineering, as well as strong opinions about the safety of the plant you may or may not share. One part lives on on the MIT website that was created to provide some more of the same, fact-based and understandable context information; the other part has hopefully inspired a couple of people to also speak their mind in a general atmosphere of panic.
3. Demand balanced and quality reporting. Demand discussions of “possible” and “most likely” scenarios in the news. Call the newspaper editor, TV station and radio station and complain about the garbage that is still put out there. Make a conscious choice regarding your news viewing, reading and listening habits. News shows are out there to produce viewers, listeners and readers that they can sell to advertisers, not quality news. If you don’t demand it, it won’t happen.

 

[ghotib]

Thanks for that 2-part post Agentm. This is a succinct statement of the approach I'm still trying to articulate for my own reading about climate science. The best part, and the hardest, is the 3 choices for what to do with the article. His choices (a) and (c) are both sloppy and/or dishonest in my view, but (b) needs time and energy that are not always available. I'd add (d) Suspend judgement.

Ghoti

 

[Agentm]

Fukushima Daiichi crisis – April 1 perspective

Posted on 1 April 2011 by Barry Brook
The Fukushima Daiichi nuclear crisis has moved off the front page of most newspapers, but a lot continues to happen, and the situation remains unresolved. Below I offer some personal perspectives on some of the things that have been widely reported over the last few days, and then I conclude with some official updates.
Disclaimer: What follows is my interpretation of the sparse and often confusing information being made available by TEPCO, NHK etc. Take or leave at your discretion.
Will the GE Advanced Boiling Water Reactor (a Gen III unit) be built at Fukushima Daiichi to replace units 1-4?

1. Plutonium detected in the soil around the plant. A few isotopes of plutonium (Pu) have been found in soil at various test sites at the FD plant. This has sent some folks on Twitter apoplectic. So where does it come from?
One theory, and quite a reasonable one, is that it is the global residual left over from the extensive atmospheric atomic weapons testing of the 1950s ”” 1970s. That would help explain the presence of Pu-238, for instance ”” an isotope not readily created in a power reactor.
Another thought is that there was a local source, either from volatilisation of sloughed material in the drying spent fuel ponds, or perhaps from the reactor cores (that was then carried away in minute traces via the vented steam). Being a heavy metal, however, the Pu would not mobilse readily and would deposit very locally. Remember, Pu is present in all spent fuel, via the U-238 –> Pu-239 transmutation pathway. All reactor fuel elements that have been fissioning will contain plutonium. It is not something peculiar to mixed-oxide (MOX) fuel (which was being used in FD unit 3), as some have implied ”” there has been a lot of nonsense written about this during the past few weeks.
In short, Pu is a metal, not a demon. Indeed, from my perspective on the Integral Fast Reactor technology, I see Pu as THE fuel of the future, and boldly predict that it will be looked back on, by some far distant civilisation, as among the most important elements humankind ever encountered. However, that’s for another post for another day. But if you want the full review now, please read Cohen.
2. Containment integrity and core damage. The story that hit the headlines was this…

Richard T. Lahey, former chair of nuclear engineering at Rensellaer Polytechnic Institute, in Troy, N.Y., was quoted as saying that the evidence he had seen indicated that fuel melted through the pressure vessel of reactor No. 2 at some point after the crisis began. He told The Guardian:
“The indications we have, from the reactor to radiation readings and the materials they are seeing, suggest that the core has melted through the bottom of the pressure vessel in unit two, and at least some of it is down on the floor of the drywell.”
​

While I respect his personal opinion as an engineer with professional experience with GE BWRs, I really don’t think he’s correct– to me, as a logical analyst, it’s just not consistent with the recent data. The reactor pressure vessel (RPV) outlet temperature, RPV internal pressure, and drywell pressure readings, have all remained relatively stable over the last few days (see latest FEPC and JAIF reports at the foot of this blog entry). I can’t see that this could possibly have been the case if chunks of molten metal had burned a gaping hole through the 8″ thick steel vessel and then fizzed through the concrete floor to boot. It certainly didn’t happen at TMI-2 in 1979, and I don’t think that it happened at Fukushima unit 2 either. Lahey seems to think his theory is supported by the high radiation readings in the water trench adjacent to unit 2… however, I disagree, as I explain in point 3.
3. Trench water. I think World Nuclear News had done an excellent recap on this: Tsunami likely filled trenches. In short:

Analysis of the trenches at Fukushima Daiichi indicates they were probably flooded by the tsunami. Low radioactivity in one trench may result from capture of radionuclides from the air but high levels in another are unexplained…
…But while an answer appears close on the presence of the water, the levels of radioactivity remain unexplained. The trench at unit 2 is a serious concern due to radiation levels from surface measurement in excess of 1000 millisieverts per hour. Further sampling has not yet taken place due to this extraordinary level, and it is not clear if the dose rate is representative of the whole 6000 cubic metre body of water, although it does match the level in the basement of the turbine building. Unit 2 suffered suspected damage to its torus suppression chamber on the morning of 15 March.
​

The key to this riddle, I think, is the wetwell torus breech (which is likely to be a pinhole or crack) ”” there has clearly been damage to containment at unit 2, but NOT, I think, to the RPV. The radioactive water in the trench could also plausibly have come from cracked/burst piping or seals elsewhere in the containment/primary system (remembering that in a BWR, the cooling water/moderator also runs through the turbine directly, unlike in a PWR). But there is no reason to think that this water comes directly from the RPV or drywell (which is where the fuel would be if it had melted through the RPV). Indeed, I think the chances of a large steam explosion at this stage of events ”” more than two weeks out from the core damage event ”” is remote in the extreme, and even if this highly unlikely chain of events did occur, it would still not spread reactor fuel over a wide area, because most of the heavier material is very difficult to mobilise and disperse (remembering that there is no burning graphite in this situation, unlike Chernobyl, and even in that accident most of the actinides stayed put).
The weird theories of Caldicott and her ilk, in which she fantasises about some ‘magical’ mechanism that is able to spread fine particulates of Pu across the landscape and into the lungs of millions of humans, and so (she outrageously claims) render the Japanese islands uninhabitable as a result, is simply beyond a joke (from many angles). Actually, it’s nothing short of appalling, grossly unscientific, hyper-alarmism.
4. Spent fuel ponds. These continue to get serious attention, with regular injections of water. They have likely been the primary source of the Cs-137 releases. The current TEPCO plan is to switch to fresh water injection ASAP. The pools in units 5 and 6 are now stable and both below 40C (see reports given at the end of this post), but there is still some concern of the pools in units 2, 3 and 4 especially. There was even a report that authorities are still considering entombing them in concrete. It’s possible, but I really don’t think that will happen because it may solve a few short-term problems, and create other longer-term site-management headaches (personal judgement).

 

[Agentm]

5. Radation levels in the ocean. These continue to be elevated close to the plant, due presumably to site run-off and the flushing/settling of airborne particles, but drop away rapidly with distance as the isotopes are spread in the ocean waters, as expected. The I-131 has a short half life, and the longer-lived Cs-137 does not bioaccumulate like mercury (for instance). I thought John Bennetts, writing in response to another BNC commenter who had earlier objected vociferously to my rather bland statement about the ‘disperse and dilute’ principle, summed it up rather well:

Firstly, to demand that a reference be provided to support the notion that 500ml of water, when mixed with the waters of an ocean, actually dilutes! I am shocked! Indeed, once the dilution factor achieves 128, then all reported isotope concentrations will be below the reporting limit, i.e. of no interest to the regulatory authorities. So what’s there to worry about? At that point, your own concerns will become baseless. As per the table at the head of this thread, three limits have been exceeded and publicly reported.
With a half-life of 8 days, the offending isotope will naturally decay by a further factor of 128 in 7*8 = 56 days, after which time you can be doubly assured that no nasty exceedances remain. I have no doubt that assessment of the real world impacts will be reviewed and assessed and talked about for some time to come, but the fact remains, that once the waters have been diluted in the Pacific, there will be no cause for further alarm. There will be no ongoing public health threat and there will be no threat to the food chain.
The only threats after dilution will be those which arise due to incomplete dilution, e.g. possible uptake in molluscs of certain species, or in aquatic vegetation, and even these will dissipate rapidly with time. I am sure that there are many suitably qualified people who will be involved in ensuring that hypothetical secondary effects are assessed and monitored and that, where doubt exists, actions such as bans on fishing are put in place. You have added precisely nought to the process of rational assessment, review and response which will ensure that the community’s health will not be damaged through these releases.
​

6. Future of Fukushima Daiichi site. TEPCO have announced that units #1 to #4 will be decommissioned once the crisis is finally closed off. Hardly surprising. I said about 2 weeks ago that 1-3 were write-offs, and although unit 4 didn’t have a fuel loading during the accident, the secondary containment has been so badly damaged by the hydrogen fires and problems with the drying spent fuel ponds that it was inevitable that it’d also be curtains. World Nuclear News has more on that story here. The decomm period is likely to take 5-10 years, based on TMI-2 experience (TMI-1 is still running, incidentally), and perhaps longer given the serious problems they’ve had with multiple reactor units. The fate of the undamaged units 5 and 6, which are some 200 m distance from 1-4, remains unresolved. I suspect they’ll eventually be put back into operation, as Japan really needs their electricity, but probably not for 12+ months. From that WNN story, there is also now speculation about whether the slated Gen III units (GE advanced boiling water reactors, similar to those built at Kashiwazaki-Kariwa in the 1990s) will be built on the Fukushima Daiichi site the future:

Tepco had planned to construct two 1380 MWe Advanced Boiling Water Reactors at Fukushima Daiichi and the start of work on these was slated for 2012. This was a delayed date as a result of additional earthquake engineering flowing from what the company learnt during a July 2007 earthquake that hit similar reactors at Kashiwazaki Kariwa. Tepco contracted for 1600 MWe of new coal generation and 4500 MWe of gas to bridge the supply gap.
​

So, at least that’s clear. Once again, it’s nuclear, or it’s coal and gas.
7. Other useful unofficial posts. Charles Barton from Nuclear Green looks at the good, the bad and the ugly side of reporting on the Fukushima crisis. George Monbiot comments on The double standards of green anti-nuclear opponents (We must apply the same standards to all energy-generating technology as we do to nuclear power). Will Davis, a former U.S. navy reactor operator, has an interesting blog going here: Atomic Power Review, with some informed theories and speculation on what the FD data mean. Worth checking out.
8. Donations to BraveNewClimate. Many people have asked about this, in the comments and privately, and I thank them for their generosity. However, I’ve always maintained that I’d rather pay for the running of the site myself ,on principle. That is, I don’t want to be seen to profit from this venture in any way, because I do it for non-monetary reasons. Indeed, it’s fair to say that I get more than enough reward out of the work by having people read my posts and for them providing a wonderful stream of comments that really makes this blog alive (even if I don’t always agree with them!). That community input makes me feel rich indeed.
(Oh, and I don’t get any $$ from the Google Ads that run ”” this is how WordPress extracts their pound of flesh for their otherwise largely free [and excellent] hosting service ”” I just pay them for domain redirection etc.).
””””””””””””””””””””””
Okay, on to some (semi-) official stuff. The latest IAEA report is here (last updated on 30 March). NEI update status here. Some snips:

At the Fukushima Daiichi site, workers continued to inject fresh water into reactors 1, 2 and 3 to keep them cool, while at the same time dealing with water that has pooled in the basements of turbine buildings and in concrete trenches near the units. As available storage space in the reactors’ condensers is filled, Tokyo Electric Power Co. is looking to store the radioactive water in tanks that will be brought to the facility. TEPCO has switched to fresh water for spraying the spent fuel pools for reactors 1, 2, 3 and 4.
All the units at Daiichi are operating on off-site electric power and work continues to connect equipment. High radiation levels and wet equipment still hampers restoration of the plants’ original machinery.
​

 

[Agentm]

Here is the latest JAIF status update, as of 1600 on 31 March 2011:

Here are links to the latest reports from the Japanese Nuclear and Industrial Safety Agency (NISA):
Conditions of Fukushima Dai-ichi Nuclear Power Station Unit 1-6(As of 14:00 30th, 2011)
Fukushima Di-ichi Nuclear Power Station Major Parameters of the Plant (As of 14:00, March 30th)
March 30th, 2011 Fukushima Dai-ichi Monitoring points
Finally, the most recent FEPC report:
• Radiation Levels
o On March 30, it was announced that radioactive nuclide I-131 was detected from the seawater sampled near the seawater discharge point of Fukushima Daiichi Nuclear Station at 1:55PM on March 29. The level of concentration was approximately 3,355 times higher than the maximum permissible water concentration set by the government.
o At 6:30PM on March 30, radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 159 micro Sv/hour.
o At 6:30PM on March 30, radiation level at west gate (approximately 3,609 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 106.3 micro Sv/hour.
o Measurement results of environmental radioactivity level around Fukushima Nuclear Power Station announced at 7:00PM on March 30 are shown in the attached PDF file. English version is available at:http://www.mext.go.jp/english/radioactivity_level/detail/1304082.htm
o For comparison, a human receives 2,400 micro Sv per year from natural radiation in the form of sunlight, radon, and other sources. One chest CT scan generates 6,900 micro Sv per scan.
• Fukushima Daiichi Unit 1 reactor
o At 7:30AM on March 29, transferring the water found at the turbine building to the condenser was suspended because the water level of the condenser became almost full. (Correction of the previous day’s report that stated as of 3:00PM on March 29, transferring the water found at the turbine building to the condenser continues.)
o At 1:00PM on March 30, pressure inside the reactor core: 0.34MPa.
o At 1:00PM on March 30, water level inside the reactor core: 1.6 meters below the top of the fuel rods.
o At 1:00PM on March 30, pressure inside the primary containment vessel: 0.23MPaabs.
o At 1:00PM on March 30, the temperature of the reactor vessel measured at the water supply nozzle: 518.2 degrees Fahrenheit
o As of 4:00PM on March 30, the injection of freshwater into the reactor core continues.
• Fukushima Daiichi Unit 2 reactor
o At 4:45PM on March 29, preparation work to recover and transfer the water found at the turbine commenced.
o At 1:00PM on March 30, the temperature of the spent fuel pool: 118.4 degrees Fahrenheit.
o At 1:00PM on March 30, pressure inside the reactor core: -0.023MPa.
o At 1:00PM on March 30, water level inside the reactor core: 1.5 meters below the top of the fuel rods.
o At 1:00PM on March 30, pressure inside the primary containment vessel: 0.1MPaabs.
o As of 4:00PM on March 30, the injection of freshwater into the reactor core continues.
o As of 7:00PM on March 30, approximately 96 tons of water in total has been injected into the spent fuel storage pool.
• Fukushima Daiichi Unit 3 reactor
o At 1:30PM on March 30, pressure inside the reactor core: 0.018MPa.
o At 1:30PM on March 30, water level inside the reactor core: 1.85 meters below the top of the fuel rods.
o At 1:30PM on March 30, pressure inside the primary containment vessel: 0.1064MPaabs.
o As of 4:00PM on March 30, the injection of freshwater into the reactor core continues.
o As of 7:00PM on March 30, approximately 4,697 tons of water in total has been shot to the spent fuel storage pool.
• Fukushima Daiichi Unit 4 reactor
o At 2:04PM on March 30, TEPCO began to shoot water aimed at the spent fuel pool, with a specialized vehicle normally used for pumping concrete.
o As of 7:00PM on March 30, approximately 960 tons of water in total has been shot to the spent fuel storage pool.
• Fukushima Daiichi Unit 5 reactor
o At 2:00PM on March 30, the temperature of the spent fuel pool: 99.0 degrees Fahrenheit.
• Fukushima Daiichi Unit 6 reactor
o At 2:00PM on March 30, the temperature of the spent fuel pool: 79.7 degrees Fahrenheit.
• Fukushima Daiichi Common Spent Fuel Pool
o At 8:30AM on March 29, the temperature of the spent fuel pool: 89.6 degrees Fahrenheit.
o As of 7:00PM on March 30, approximately 130 tons of water in total has been injected to the spent fuel storage pool.
Our official sources are:
• Office of The Prime Minister of Japan
• Nuclear and Industrial Safety Agency (NISA)
• Tokyo Electric Power Company (TEPCO) Press Releases
• Ministry of Education, Culture, Sports, Science and Technology (MEXT)

 

[IFocus]

I have been wondering why there has been no news of robots being used


Robots fail a nation when needed the most

WASHINGTON: Inside a nondescript warehouse south of Mannheim, Germany, a dozen robots, ranging in size from a low-slung inspection bot no bigger than a toy wagon to a 22-tonne Caterpillar excavator, stand ready to respond to a nuclear emergency.

With their electronics hardened to withstand radiation, the versatile machines can handle fuel rods as well as monitor doses that would kill a human engineer. A similar robotic quick-response squad is housed near the Chinon nuclear power plant in France.

In Japan, where the Fukushima nuclear crisis is three weeks old, the question is: Where are the robots?

http://www.smh.com.au/technology/te...tion-when-needed-the-most-20110401-1cro0.html