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@jt I saw Drunken Angel recently. Toshiro Mifune played a yakuza gangster who has TB, and he can't break free of his lifestyle to get well. Excellent.

Thursday, May 26, 2011

Cooling pipe breach now laid to temblor
Reactor design rethink looms after Tepco damage report
Kyodo
Tokyo Electric Power Co. admitted Wednesday that one of the critical cooling pipes at its Fukushima No. 1 nuclear power plant's reactor unit 3 may have been damaged in the March 11 megaquake.

Tepco suggested earlier that no major damage, including ruptures in the facility's main steam pipes, had occurred at the reactor until the massive tsunami hit after the magnitude 9.0 quake.

But if the temblor had actually damaged the High-Pressure Core Flooder system — which is used to supply coolant water to a reactor core in emergencies to keep nuclear fuel from overheating — power suppliers across the country might be forced to reconsider the quake resistance designs for their reactors.

"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.

"We can't deny the possibility," the official added.

At the No. 3 reactor, a quake greater than anticipated under resistance guidelines occurred, knocking out electricity to the power plant and precipitating the current crisis.

The piping was housed in a building that was designed to resist direct damage from tsunami.

Another analysis by Tepco has shown that breaches may have occurred at containment vessels encasing reactors 1 and 2 at the power plant, possibly causing leaks of highly radioactive water there.

The possible breaches to the containment vessels there are certain to compound efforts to deal with accumulating contaminated water at the sites, raising questions about the viability of a Tepco plan to re-establish a stable cooling system by around mid-July.

Tepco said if it hypothesizes that a breach of about 3 cm wide occurred at the reactor 1 containment vessel 18 hours after the quake and widened to about 7 cm 50 hours later, that corresponds well to changes in pressure readings inside the containment vessel.

The utility also hypothesized that a breach roughly 10 cm wide occurred at the No. 2 reactor's containment vessel 21 hours after the quake due to elevated temperatures, among other factors.

This finding also corresponds with data obtained.

Tepco also said it believes that parts used to ensure air tightness may have broken from overheating.

Projections halted
Kyodo
The Meteorological Agency has stopped providing projections of the spread of radioactive substances from the Fukushima No. 1 nuclear plant now that the International Atomic Energy Agency is no longer requesting them, agency officials said Wednesday.

The IAEA had asked for the projections to gauge the potential impact on other countries of radiation leaking from the nuclear plant following the megaquake and tsunami.

The projections were made up to three times a day immediately after the crisis erupted and, recently, three times a week in reports to the IAEA.

The Meteorological Agency had made the projections available on its website since April 5 as instructed by the government.

The IAEA terminated the request Monday night without specifying why and noted it could make a new request if there were any developments to warrant it, Japanese officials said.

However, the agency will not give projections unless the U.N. nuclear watchdog asks them to, the officials said.

The projection had been based on an assumption that 1 becquerel of iodine-131 is discharged from the nuclear plant every 72 hours. Projected concentration data did not reflect reality.
search.japantimes.co.jp

@RBeaner I am confused, It's easy for me,,, but is this your comment or marie rich? are you leaving also?

@fitter I "left" earlier, because I was "derogatory". But I hate to see where this place is left. "for evil to succeed....Yada yada... This is my quote of a coomment from Marie. I couldn't care less if they are the same person, if they have something to contribute.... To the overall knowledge of the group.

@fitter, did you see the two BWR manuals Dean etc. posted in the last week?

@Nancy seen them, but not able to print (to long) and have been working on the piping systems, they are extrenly complex in how they tie into each other... then hey have so much redundency for safety its like looking at three separete plants in one... also these drawings are us and i cut the title box and notes in half... so i only have half a note

@Lethbridgean Yes, the witch hunt continues. Am I an "astroturfer"? Is XXX and Mexico_lurker the same person.... Who cares?

@RBeaner, that was a joke !!!!

1. General, Basic Radiation Worker Knowledge of Internal Whole Body monitoring for radioactivity www.iem-inc.com

2. ORTEC www.ortec-online.com and CANBERRA www.canberra.com are well known sellers of these complicated monitoring systems.

3. Here is a scientific article of a 2002 internal radioactivity investigation of several workers exposed in a Korean NPP. It helps show how complicated it is to assess dose to the worker when the activity is internal. www.google.com

4. Generally speaking, external radiation exposure is easily quantified and widely understood when measured with a dosimeter. There isn't really any dispute as to what the radiation exposure was to the worker. The health effects of that exposure continue to be a source of some dissagreement. Internally deposited radioactivity must be assessed through complicated calulations. Some presumtion of the actual isotopes inside the body must be made. This falls into the area of Counting Statistics (of which I only have general familiarity).

5. After a person receives Whole Body Monitoring (using extremely sensitive gamma detecters). The computer analyses the Spectrum (energies) of all the gammas generated and then spits out the EXPECTED activities and isotopes (for ex CS-137 and I-131). The accuracy of this equipent is not really great, It is allowed to be off up to 50% in many cases. This is due to geometry mostly. How thick is the chest, is it muscle, breast or thicker than the average bone density etc... These are all factors that can only be estimated for the count of each worker.

6. The above is why the nuclear field goes through great lengths to prevent uptake (internal) radioactivity. This stuff has legal ramifications for the npp, so they really try to avoid it in normal operation and maintenance.

7. Internal monitoring is required (in US) annually for occupational radiation workers, Internal exposure monitoring (not necessarily individual monitoring devices) is required: For adults likely to receive in 1 year an intake in excess of 10% of the applicable ALIs for ingestion and inhalation.
For minors and declared pregnant women likely to receive in 1 year a committed effective dose equivalent in excess of 0.05 rem (0.5 mSv). www.nrc.gov


8. Good Idaho State University website talking about radiation and relative health effect www.physics.isu.edu

9. Good (understandable) discussion paper on how the International Commission on Radiological
Protection (ICRP) approaches and views Internal exposure and monitoring www.google.com

@wtm just the drawings on the floor drains and equipment waste take hours to decifer.... not spending much time on them...

@wtm elene has comment on vent supports, but i missed the original conversation... would like to find the info if you know how far back it is!!!

@fitter, don't know if there was ever anything mentioned on it ? Figured by now the structural design against the quakes would have come up someplace from somebody ? But then again, these are the same people who designed the open top SFP. Guess they just figured the RPV was heavy enough to just sit still in the bottom of the CV and not move around by itself?

@fitter, is that to support the weight of the pipe, or actually a support between the RPV and CV to stop RPV sway ?

@fitter, OK TY !

@wtm do not know.. supports are a very very complex desigin and most bids will state that 2" and under (NOT NUKE HOUSES) are not show... and we exclude them in our price!!!!!

@MarkFm, its good to see your fingers work as well as mine in the morning ?

@all, Drudge ran a byline story on the Japan TEPCO story about the 3 meltdowns this morning !

@fitter There is alot of old news, that supports a high ground water leve.. I can't produce most of it today, but heres this www.asahi.com

The media is concentrating on the tornado news right now !!

@RBeaner on ground water do you know or understand what "thier" DEFFENITION of groungwater is, I still don't know if its natural graound water level... or includes all the water they have used along with runoff water???? old new is good

@fitter I read . on a link earlier, (i can't produce it) That they (fuku daichi) has to continuously pump groundwater out from below the plan

IAEA at it's best !!
Agency stops giving projections of radioactive substance spread

Wednesday 25th May, 03:06 PM JST

Print

TOKYO —

The Japan Meteorological Agency has stopped giving projections of the spread of radioactive substances from the Fukushima Daiichi nuclear plant as the International Atomic Energy Agency is no longer asking for them, JMA officials said Wednesday. The IAEA had requested the projections to gauge the potential impact on other countries of the damage to the nuclear plant from the March 11 earthquake and tsunami.

The projections were made up to three times a day immediately after the disaster and, recently, three times a week to report to the IAEA. The agency had made the projections available on its website since April 5 as instructed by the government.

The IAEA terminated the request Monday night without specifying any reason and noted it could make a new request if there were any developments, the JMA officials said.

The agency will not give projections unless the U.N. nuclear watchdog asks them to, they said.

The projection had been based on an assumption that 1 becquerel of iodine-131 is discharged from the nuclear plant every 72 hours. Projected concentration data did not reflect reality.