* Posts by dlapine

7 posts • joined 14 Mar 2011

Elon Musk scrubs lucrative MONEY RING debut again on Thanksgiving


Time for a new article perhaps

As the SES-8 satellite sits in it's desired delivery orbit this evening. SpaceX's delay seems to have been well used.

At less than $100M for this launch, SpaceX appears to providing some real competition to those other US space companies...

Mummy, mummy, there's a nuclear monster!


Interesting information

I didn't know that the sensor in Unit 1's drywell had failed. The wordpress site is run by a Dr. Daniel Garcia, a Spanish Ph.D posted at JAEA. Thanks for another source of information and the link to current data- there was no mention on the other NISA site as why they hadn't updated anything for 3 days.

Looking at your spreadsheet, especially on the CAMS_DOSE sheet:


I notice that the levels that the drywell sensor in unit 1 (the dark blue line) have been reporting have been anything but a smooth descending curve, compared to either of the other units' drywell sensors or unit 1's own sensor in the suppression chamber. I'd disagree with your assessment that unit 1's drywell readings were declining, unless the sensor failed on 3/27. But that would be cherry-picking a data point , wouldn't it? In fact, it appears that all units are flattening out at their current levels of emission. The curves are not suggesting a further decline of significance.

I will note that the working suppression chamber sensor in unit 1 is still a good 10 S/hr higher than the same reading at the other 2 units. Interesting to see a 50% spike in that reading on 4/7, just proceeding the "errant" reading from the drywell sensor. From the notes, this corresponds with the start of the N2 injection.

Could the N2 injection have caused the sensor to fail?

Why are the radiation levels (as we know them) still so high in unit 1?

Given the updated information you pointed me at, it's hard to interpret the recent readings in unit 1 as a reactor breach. I'm happy to have data that conflicts with that possibility. I should not have suggested that conclusion without more corroborating evidence. I still think that unit 1 has severe issues, but I'm not sure what might be causing them.

As for cherry-picking data points, don't you know that it's bad form (when cherry picking) to point out both the high and low points of the plot, note where the median lies, and only use the median in your examples. And then to mention that high spot only once and that only when describing the range, well that's just inexcusable for narrative building. To actually provide a direct link to the full information defeats the while purpose. I guess that I'm not very good at it. :)

To sum up, I believe that you mentioned the figure "50 uS/hr" in your response more often than the single time I did in my original post. Perhaps I didn't say what you think I did.

I was noting that the figure of 1.6 uS/hr was inaccurate for the entire area when used to measure human safety, not claiming that 50 uS/hr was a more accurate number.


Some good points

Thanks for taking the time to bring up these points and do some research.

I'm not sure what about you're referring to in the thermograph- it's a picture of reactors 3 & 4, not unit 1. The hot spot you see is in unit 3, on the right, which corresponds to the location of the spent fuel pool in unit 3, which is visible through the debris of the roof.

My point (and the poster's) is that there is no corresponding "hotspot" for unit 4. Where is that spent fuel?

As for the suggested breach in unit 1, I was going by the release of radiation on the 8th, not the containment pressure. You bring up a good point in noting that the unit is still holding pressure, so any breach of the steel walls of the reactor is unlikely. If the current tactic to vent steam into drywells has been going on since the beginning of April, I'm willing to listen to any explanation of why the radiation levels more than doubled on the 8th.

I do note that the NISA data shows a steady increase in pressure for the reactor vessel in unit 1 and that at 904 kPA, that unit is currently at 10x the pressure of the other 2 units. The unit is smaller, with about 2/3 the generating capacity of units 2-6. That might expand some pressure difference, but not an order of magnitude, and not a 50% increase since the initial event.

Please note that the information provided in your link is not the same as the NISA status page, as this information does not have the specific radiation/temp/pressure readings per reactor, just a summary of the beliefs of the JAIF. They are an industry body, not a regulatory agency. Let's stipulate that I trust NISA information more than JAIF.

And no, I don't read horror novels, and I don't secretly long for the status at Fukushima to become any worse than it is. I do, however, have a degree in engineering, and I run supercomputers for a living. When something breaks, we try to discover the cause of the failure. We don't run around waving our arms in the air crying "The sky is falling!", nor do we stick our heads in the sand and proclaim, "nothing to see hear, move along".

I'd like some explanation as to why the pressure and released radiation for that unit keep climbing, weeks after the event. Increased pressure alone would seem to imply increased heat production in that reactor.

I'd also like to see the data updates restart from NISA.

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Some More information and less opinion, please

Well, given that it's been a week since we heard anything from Lewis on this, I thought he was in hiding. It's not like the news has been any kinder to the situation.

First off, let's start with published data: http://www.mext.go.jp/english/radioactivity_level/detail/1304082.htm

These are readings around Fukushima, out to 40km. They have daily updates on the dosage levels.

Please note that the hightest rating is over 50 microsieverts/hr, not 1.6 as noted by the MIT guys. There's another site at 25, and several over 10, and many reading above 3.

Is 10 microsieverts/hr going to kill you? No, I'm not saying that is. 240uS/day is about 85 milisieverts a year, which is much higher than the background rate, but not immediately threatening, but the point here is that reporting the measured rates at only 1.6uS/hr is misinformation. Took me all of about a minute to find that data, too.

Lewis concentrates too much on iodine, as other have noted. Cesium-137 levels 1600x the normal rate have been found in Iitate village. This is the stuff with a 30 year half-life. This is what drives the creation of an evacuation zone.

Article here: http://www3.nhk.or.jp/daily/english/23_28.html

Also, I notice that Lewis is completely ignoring the spent fuel pools, and the status of the "open to the atmosphere" fuel rods in them. In this case, we don't have to have a reactor breach to release serious sources of radiation, as the water in the fuel pools was gone at one point. I'd note that the spent fuel rods in 4 were active enough to:

1) boil off the water

2) react with the water vapor to generate H2

3) and blow the roof off of a unit where the reactor was even in operation.

That's with only 0.37% of the power (as Lewis notes) that the rods in the other 3 cores have going for them.

So where is the fuel from the spent fuel ponds? Unit 3 looks to be where it's supposed to, but Unit 4's fuel from the spent pool seem to be missing. The analysis here is interesting:


followup here:


If you want some real inside information, look at these numbers from NISA:


These are the operating numbers from the 3 reactors for temperature, pressure and radiation, probably from the normal monitoring units. I've pointed you at unit 1, because it's the most troubling. Yes, those units are Sieverts/hr, no mili or micro, full up, "put hair on your chest" sieverts. You know, the 1S that Lewis described as, "...probably won't kill you". Given that these reading are from just outside the reactor core and from the suppression ring (the torus), I would expect them to be high. But 100 Sieverts/hr near the core? 12 S/hr in the torus? Look at the numbers for the other active units. Neither unit's 2 nor 3 are anywhere near those levels.

What's telling is that NISA hasn't released any new data for the last 3 days.

This speaks of a core breach in unit 1. Perhaps not the concrete containment structure (fully 40 feet thick at the bottom), but it appears that the reactor in unit 1 has been breached. If that's the case, then prospects for further release of radiation have increased. Perhaps this is what is driving the higher classification.

I think the Reg might be better off putting Lewis' unending admiration for the nuclear industry aside, and let someone do some actual reporting. Just because I support the idea of nuclear power, doesn't mean that I need to be a cheerleader for the power companies, and the way things are run now.

Fukushima update: No chance cooling fuel can breach vessels

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Updated facts

1) The Japanese government released information that the highest level of radiation at the plant was up to 400,000 microsieverts, not ~8000. That was during the fire in the fourth reactor building, where spent fuel rods were being stored. -http://www.dw-world.de/dw/article/0,,14911490,00.html. Reports state that the level has decreased considerably and is being monitored.

2) 400K microsieverts is potentially hazardous to human health. Anything over 1000K microsieverts or 1 sievert is the dose where humans start to die. These are not insignificant amounts of radiation.

3) The substructure of reactor 2 has been damaged, and the fuel rods in that reactor were without water for up to 5.5 hours. The pressure in the reactor was so high that the firehoses used to pump seawater into the reactor could not overcome it. They had problems releasing the pressure as the the emergency relief values were stuck due to lack of power and nitrogen gas used in the backup system.

4) The Japanese government has already stated that some fuel rods at reactors 1, 2 & 3 had "probably" melted to some extent

5) "The head of France's nuclear safety authority, Andre-Claude Lacoste, said Japanese officials had briefed him, saying the concrete vessel around the Number 2 reactor at Fukushima was no longer sealed. " This statement has not been confirmed.

6) "Lacoste also said that the Fukushima accident now rated a six on the international seven-point scale of severity, up from four, putting it second to the Chernobyl disaster in Ukraine and ahead of Three Mile Island in the US state of Pennsylvania as the world's worst nuclear accidents."

7) "The No.4 reactor's cooling pool, where spent nuclear fuel is stored, may be boiling and the water level may be falling" This is the reactor where the fire occurred, possibly as a result of uncooled spent rods. "Radioactivity at the cooling pool is high and Tokyo Electric cannot make checks at the site or determine what has burned." -http://www.reuters.com/article/2011/03/15/japan-quake-keypoints-idUSL3E7EF16720110315

8) "The government gave no update on the status of a steel container surrounding the core of the plant's No.2 reactor, deemed by observers as most at risk of a meltdown."

Stating that there is no possibility of a containment vessel breech at this time is an opinion, unfettered by facts.

It's possible that the vessel has already been breeched, but reported radiation levels don't seem to indicate it.

Given the damage to site already, it's possible that TEPCO has no working monitors left in the reactor and wouldn't be able to discern a small breech.

Even assuming the containment holds at the moment, if the #2 reactor loses seawater cooling for a further length of time, the rods inside in the core will melt and produce a much larger amount of heat. Given that the relief values have already had issues, the constrained stream could certainly generate enough force to breech the vessel. It might be unlikely, but certainly not "impossible"

Another reasonable possibility for the release of unacceptable levels of radiation (as a core breech isn't the only way to put human life at harm's risk) is that the "already out of the containment vessel" spent rods stored in reactors 4,5 & 6 might also lose cooling and melt, thus releasing their radioactive cores into the atmosphere directly. Given that the rods in unit 4 have lost cooling once, and that temperatures in units 5 & 6 are rising, we have yet another way to potentially expose the public.

At this point in time, there are many ways for the plant to release radiation at unacceptable levels.

Please stop trying to soft sell the issue.

Fukushima is a triumph for nuke power: Build more reactors now!


Also, consider the information this article from the Reg


I don't believe that we can consider this a minor release of radiation:

"The hourly amounts are more than half the 1,000 micro sievert to which people are usually exposed in one year.The maximum level detected so far around the plant is 1,557.5 micro sievert logged Sunday."

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Missing a Few facts

Please note that I'm a fan of nuclear power, but let's include all the facts, shall we?

1) the 8.9 magnitude was at epicenter. At Sendai, the earthquake was about a 7. The plants were claimed to be designed to withstand a 7.9 on site.

2)pumping seawater into a reactor is a last resort, not just a line of defense. Once you put seawater into the building, they will have to close that unit permanently.

3)The radioactivity released was sufficient to be detected by the USS Ronald Reagan which was 100 miles off the coast. The claimed dosage was "1 month's worth in an hour" and the carrier was ordered to move out of the path of the radiation plume. -http://latimesblogs.latimes.com/lanow/2011/03/carrier-ordered-further-away-from-radiation-from-japanese-nuclear-plant.html

4) the explosions were caused by a hydrogen explosion in the outer containment building. The plant is supposed to have hydrogen gas burn out systems to prevent such explosions and they obviously failed.

5) the hydrogen generated inside the reactor was due to the reaction of the zirconium cladding of the fuel rods interacting with the cooling water- which implies:

- a) the rods were hot enough to react

- b) portions of the rods were no longer covered by water

- c) that the steam and radioactivity released had been INSIDE the containment vessel and released through the emergency relief values

6) A third reactor has lost coolant pressure. You're touting the safety and design of a plant where they can't get and keep emergency generators online in 72 hours? Really?

7) As a note, reactor 1 was 40 years old, and due to shutdown in 1 month. Reactor 3 just had a 10 year renewal after inspection.

8) Lastly, the Japanese cabinet minister, Edano has been giving statements throughout, each of which has been understating the situation and downplaying the real events. I don't think that some level of scepticism is unreasonable about the official reports.

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