What "might happen" with the Japanese Nuclear plants?

[GreyGeek]

Re: What "might happen" with the Japanese Nuclear plants?

P.S.: Here is a site with excellent before and after pictures (up to June 10th) of Fort Calhoun and Cooper Nuclear stations. It also shows the 1993 flood at Cooper nuclear which got into the basement of the reactor building, shorted out the power driving the cooling water in the reactor core, causing the plant operator to do an emergency shutdown.
http://cryptome.org/eyeball/ne-npp-f...-npp-flood.htm


P.S. P.S. -- I forgot to mention that the bladder protecting the reactor, security and admin building is NOT protecting the 'mausoleum' holding the spent fuel rods. The pool was so full in 2009, they were sealing the fuel rods up in dry casks and sticking them in an on-site ‘mausoleum’, instead of putting them in the cooling pool.

On June 16, however, a U.S. Nuclear Regulatory Commission (NRC) event report involving penetration and potentially water pumps at the Ft. Calhoun Nuclear Station: “Potential flooding issue in the Intake Structure,”: “There is one penetration of concern” that could impact water pumps. The report included:

"Operations identified a potential flooding issue in the Intake Structure 1007 ft. 6 in. level. The area of concern is a the hole in the floor at the 1007 ft. 6 in. level where the relief valve from FP-1A discharge pipe goes through the raw pump bay and discharges into the intake cell. There is one penetration of concern. Flooding through this penetration could have impacted the ability of the station’s Raw Water (RW) pumps to perform their design accident mitigation functions."

In the Licensee Event Report 2011-003, Revision 1, for the Fort Calhoun Station, NRC, May 16, 2011, it was reported, "As a result of a Nuclear Regulatory Commission (NRC) inspection conducted from January 1 to June 21, 2010, the NRC determined that Fort Calhoun Station (FCS) did not have adequate procedures to protect the intake structure and auxiliary building against external flooding events."

The May 16 report furthered:
"During identification and evaluation of flood barriers (condition report (CR) 2010-2387), in response to NRC findings previously noted, unsealed through wall penetrations in the intake structure were identified that are below the licensing basis flood elevation. These penetrations were installed during the installation of upgrades to the plant fire protection system. As a result of the penetrations not being sealed, the intake structure was vulnerable to water inflow during an extreme flooding event. This inflow had the potential to affect the operability of both trains of safety related raw water pumps (ultimate heat sink)...."

In case you didn't catch it, the UHS is the source of cooling water provided to dissipate reactor decay heat and essential cooling system heat loads after a normal reactor shutdown or a shutdown following an accident, including a loss-of-coolant accident (LOCA).

The Fort Calhoun reactor was shut down in April BUT they only removed 1/3rd of the spent fuel rods and, as you know, shutting down a reactor doesn't mean it instantly cools off. It needs to be continually cooled for over a year after it's chain reaction is stopped in order for most of the short half-life daughter products to decay and their heat dissipate.

So, the short story is that the two Nuke plants are hanging on by the skin of their teeth, and the Forth Calhoun plant is especially vulnerable, even more so now that the Gavins Point Dam has jacked up its release rate to 160,000 cfs.

[woodsmoke]

Re: What "might happen" with the Japanese Nuclear plants?

I SAY HOLMES!

Just HOW did you know that?

Quite simple Watson! I see while you look!

So.........Mr Gray Geekness just HOW DID YOU SEE THAT?

It shows that both the intake and exhaust cooling water ports are below the water level.

Inquiring minds want to know or are we to assume that you have a blue and red suit with cape and both telescopic AND x-ray vision?



And if we are not to assume that your name is BOND....GRAY BOND!!! 8)

how did you come up with that site?!



Very interesting GG, very interesting!

woodsmoke

[GreyGeek]

Re: What "might happen" with the Japanese Nuclear plants?

I SAY HOLMES!

Just HOW did you know that?

Quite simple Watson! I see while you look!

So.........Mr Gray Geekness just HOW DID YOU SEE THAT?

It shows that both the intake and exhaust cooling water ports are below the water level.

Noting this:

"As a result of a Nuclear Regulatory Commission (NRC) inspection conducted from January 1 to June 21, 2010, the NRC determined that Fort Calhoun Station (FCS) did not have adequate procedures to protect the intake structure and auxiliary building against external flooding events."

AND comparing pre and post flood photos of Fort Calhoun it is easy to see that the intake and exhaust ports shown in the pre-flood photos are NOT visible in the post-flood photos.. As Snowhog Holmes says, "Elementry my dear Watson". No blue suit or red cape needed.

Also, noting that the Gavin Point dam increased their release to 160,000 cfps, I was very concerned about an incident at both plants. Cooper's levee was only FOUR INCHES away from topping last night! But, a miracle happened during the night. Three miles upstream from Cooper the levee fortunately broke, flooding the surrounding country side and lowering the level at Copper by a little over a foot. I suspect that the levee above Fort Calhoun may miraculously break as well, if things get worse.

Google has some amazing search options.

[woodsmoke]

Re: What "might happen" with the Japanese Nuclear plants?

ummmm too many rum 'n cokes!

thanks GG

woodsmoke

[GreyGeek]

Re: What "might happen" with the Japanese Nuclear plants?

The situation at Fort Calhoun has gotten worse!

CBS News reported that at 1:30 a.m. Sunday morning the eight foot high rubber bladder berm surrounding the plant collapsed!

A berm holding the flooded Missouri River back from a Nebraska nuclear power station collapsed early Sunday, but federal regulators said they were monitoring the situation and there was no danger.
...
there is no water inside the plant,
...
the river is not expected to rise higher than the level the plant was designed to handle.
....
the berm wasn't critical to protecting the plant
....
The berm's collapse didn't affect the reactor shutdown cooling or the spent fuel pool cooling, but the power supply was cut after water surrounded the main electrical transformers, the NRC said. Emergency generators powered the plant Sunday while workers tried to restore power.
....

In response to the May 16th NRC report which said that flooding of the input/output cooling water pipes could lead to a meltdown the plant's defenses were modified. The NYT said that "The plant's defenses now include new steel gates and other hard barriers protecting an auxiliary building with vital reactor controls, and a water-filled berm 8 feet tall that encircles other parts of the plant. Both systems are designed to hold back flood waters reaching 1,014 feet above sea level. Additional concrete barriers and permanent berms, more sandbags and another power line into the plant have been added." The New York Times article gives a good analysis of the fight between the OPPD and the NRC on what level of preparation is required for assured safety.

New defenses still under evaluation

The NRC responded in its October 2010 letter that once flooding reached 1,004 feet, water would have entered the plant and the ability of emergency workers to move around the site would "significantly degrade."

If levels exceeded 1,004 feet, water would reach the lower floodgates, hampering the welding of plates to door frames, the NRC said. At 1,008.5 feet, the technical support center used by emergency technicians would have been inundated. At 1,010 feet, water would begin to enter the auxiliary building, "shorting power and submerging pumps. The plant could then experience a station blackout with core damage estimated within 15 to 18 hours," under a worst-case scenario, the NRC said.

The NRC concluded that the use of the fire truck for emergency pumping would fail, after it determined the truck could not draw floodwaters successfully from the turbine building. Moreover, it was not clear how workers could operate a crane to lift the fire truck into position if outside power were lost, the NRC staff added.

The NRC has not completed its evaluation of the new defenses installed at Fort Calhoun, nor has it resolved how OPPD handled the new information about flood threat that the NRC says the utility received via the Corps of Engineers.

On June 18th, after rumors of a possible meltdown at Fort Calhoun, the OPPD and the Governor used the Berm as proof that

flood water pumped into a giant donut around the Fort Calhoun Nuclear Power Plant was put there to keep flood water out. Officials called it an "aqua berm."
...

Suddenly, with the input/output ports under water, and the bladder having collapsed and not able to "keep the water out", we are supposed to "not to worry, everything is under control".

Time will tell. But, even if they manage to patch and re-inflate the Berm, the 160,000 cfps flood waters will continue to rush out of the Gavin Point Dam for several more weeks. It is still my suspicion that if the water level gets critical again, or failures at the plant create imminent danger, levees above Fort Calhoun will fail, allowing water to escape into the farm land, lowering the water level at the plant, just the way it happened at the Cooper Nuclear plant nearly 100 miles to the South.

An aside: Here is an interesting article on the conversion of the mission of the U.S. Army Corps of Engineers (USACE) from "taming the Missouri by constructing a series of six dams" to one "that would make ecosystem restoration an "authorized purpose" of the dam system.". The initial idea was simple: massive dams at the top moderating flow to the smaller dams below, generating electricity while providing desperately needed control of the river's devastating floods. Now, however, the goal is for "habitat restoration, wetlands preservation, and culturally sensitive and sustainable biodiversity."

Congress created a committee to advise the Corps on how best to balance these competing priorities. The Missouri River Recovery and Implementation Committee has seventy members. Only four represent interests other than environmentalism. The recommendations of the committee, as one might expect, have been somewhat less than evenhanded.

The Corps began to utilize the dam system to mimic the previous flow cycles of the original river, holding back large amounts of water upstream during the winter and early spring in order to release them rapidly as a "spring pulse." The water flows would then be restricted to facilitate a summer drawdown of stream levels. This new policy was highly disruptive to barge traffic and caused frequent localized flooding, but a multi-year drought masked the full impact of the dangerous risks the Corps was taking.

This year, despite more than double the usual amount of mountain and high plains snowpack (and the ever-present risk of strong spring storms), the true believers in the Corps have persisted in following the revised MWCM, recklessly endangering millions of residents downstream.

The role reversal of the Corp occurred around 1980. Of the thirty three historical crests for the Missouri river near Blair, NE, four are in the 1950-1980 time frame. TWENTY NINE fall in the 1980-2011 time frame.

Considering that this year the snow and precipitation totals in the Missouri basin are between 3 to 12 times more than average, which is why many experts are saying that the flooding may continue through the late fall and perhaps up to December.

[GreyGeek]

Re: What "might happen" with the Japanese Nuclear plants?

Radiation is not the only thing leaking out of the Fukashima meltdowns.
http://fairewinds.com/updates
The video is here:
http://vimeo.com/28014740

Newly released neutron data from three University of California San Diego scientists confirms Fairewinds' April analysis that the nuclear core at Fukushima Daiichi turned on and off after TEPCO claimed its reactors had been shutdown. This periodic nuclear chain reaction (inadvertent criticality) continued to contaminate the surrounding environment and upper atmosphere with large doses of radioactivity.

In a second area of concern, Fairewinds disagrees the NRC's latest report claiming that all Fukushima spent fuel pools had no problems following the earthquake. In a new revelation, the NRC claims that the plutonium found more than 1 mile offsite actually came from inside the nuclear reactors. If such a statement were true, it indicates that the nuclear power plants containment failed and were breached with debris landing far from the power plants themselves. Such a failure of the containment system certainly necessitates a complete review of all US reactor containment design and industry assurances that containments will hold in radioactivity in the event of a nuclear accident. The evidence Fairewinds reviewed to date continues to support its April analysis that the detonation in the Unit 3 Spent Fuel pool was the cause of plutonium found off site.

Third, the burning of radioactive materials (building materials, trees, lawn grass, rice straw) by the Japanese government will cause radioactive Cesium to spread even further into areas within Japan that have been previously clean, and across the Pacific Ocean to North America.

And finally, the Japanese government has yet to grasp the severity of the contamination within Japan, and therefore has not developed a coherent plan mitigate the accident and remediate the environment. Without a cohesive plan to deal with this ongoing problem of large scale radioactive contamination, the radioactivity will continue to spread throughout Japan and around the globe further exacerbating the problem and raising costs astronomically.

The appearance of a radioisotope of Sulfur over California, coming from Fukashima, was the result of neutron bombardment of sea water used to cool the reactors and, as back calculations show, at a rate of at least 400 Billion Neutrons per second per cu meter. When a Neutron hits an atom of Sodium it is converted into radioactive Sulfur-35, which is absorbed by the entire body but concentrates in the testitcles. The Neutrons could ONLY have come from the fission of Uranium and/or Polonium. Since Fukashima was a mixed reactor both fuels were present. This could only mean that the reactor cores had melted into a pool of molten metal at the bottom of the reactors and were undergoing periodic chain reactions. This explained the blue radiation glow appearing in the air over the reactor buildings.

Now, a new phenomena is being observed. Steam is escaping from the ground in the vicinity of the reactors. http://bojack.org/2011/08/at_fukushi..._cracks_i.html
There are reports that the Japanese government and the Tokyo Electric Power Co are forcing Japanese to remove YouTube videos about the radiation and reactor related news around their communities.

And, levels of radioactivity several times higher than allowed standards have been measured in various places in the West: http://uk.ibtimes.com/articles/20110...134-indica.htm. Both Canada and the US have stopped measuring levels of radiation drifting over from Fukashima.

[MoonRise]

Re: What "might happen" with the Japanese Nuclear plants?

Yep. Dire, dire situation for ALL. After VA earthquake and that reactor near there shutting down due to "over sensitive" instruments, who knows, we may be helping soon as well.

[GreyGeek]

Re: What "might happen" with the Japanese Nuclear plants?

A report has been released which estimates the total radioactive materials released from the Fukashima reactors, using Xenon-133 and Cesium-137 as "tags'.
http://www.atmos-chem-phys-discuss.n...28319-2011.pdf

Regarding the noble gas Xe, it is very likely that the accumulated inventory of the reactor units 1–3 was completely set free into the atmosphere between 11 and 15 March. The study indicates a total release of 16.7 (uncertainty range 13.4–20.0) EBq, which is the largest radioactive noble gas release in history not related to nuclear bomb testing. The release is a factor of 2.5 higher than the Chernobyl 133 Xe source term. There is also strong evidence that the start of the release occurred early, already during or shortly after the automatic emergency shutdown of the reactors triggered by the big earthquake. This early onset of missions is interesting and may indicate some structural damage to the reactor units during the earthquake.

Regarding Cs, the inversion results indicate a total emission of 35.8 (23.3–50.1) PBq, or about 42 % of the estimated Chernobyl emission. This means that nearly 2 % of the available inventory of the reactor cores in units 1–3 and the spent-fuel pool in unit 4 was discharged into the atmosphere.
....
These early emissions were until now underestimated by the Japanese authorities, but are in accordance with the first estimates published by Central Institute for Mete-orology and Geodynamics (2011)137

As usual, Arnie Gundersen spells out the events on the #3 reactor and cooling pool, which experienced a "criticality" (unconstrained fission explosion)
http://vimeo.com/30816614


If there is good news in this report, it is that the half-life of Xenon-133 is 5.2 days, meaning that within two months the majority of it will have decayed way to stable Cesium-133. Unfortunately, the Cesium-137 which was released will be around for 300 years...

[woodsmoke]

Re: What "might happen" with the Japanese Nuclear plants?

Interesting your greygeekness....but....

Ahem.....

A....

unconstrained fission explosion

Which was "SUPPOSEDLY" not to happen in a reactor.

"SUPPOSEDLY' a reactor was only supposed to undergo a "steam" explosion.

definition of fission explosion

If your GreyGeekness would care to expound on that I think that many readers would appreciate said expoundness.

BTW, I stopped teaching the "liquid drop" model of the nucleus a couple of decades ago,(Phy Sci, Chem, Physics) (I USED to teach several models) in favour of the particle model which "most" textbooks now use...but, is seems that I should reconsider that for at least my Physical Science for Elementary Education Majors class.

woodsmoke

[GreyGeek]

Re: What "might happen" with the Japanese Nuclear plants?

IF nuclear reactor designs didn't skip on safety and IF nuclear reactor builders didn't falsify weld reports, or short the lime in their concrete mix, or falsify x-rays of critical welds, etc..., AND, if Japan hadn't had a 9.0 earthquake which dropped the Eastern shore of Japan by more than 1 meter, AND if Japan wasn't hit by the worst tsunami in centuries, then a criticality would not have occurred.

An atomic bomb undergoes a chain reaction. That reaction is enhanced by surrounding the core with compression explosives and surrounding the explosives with a very strong Steel alloy which confines the whole device and prevents the core material from breaking apart too quickly. This enhances the number of Neutrons which can travel a Barn distance, guaranteeing that they will collide with another Uranium-235 atom. The Hiroshima A bomb split 1 gram of U-235 before the resulting energy overcame the explosive compression and surrounding K-46 Steel tamper rings and blossomed into a fireball one mile across

IF an amount of U-235 which has melted and collected in the bottom of a reactor vessel chamber, or the bottom of a spent fuel pool exceeds a Barn diameter (the distance a slow Neutron can travel before hitting another nucleus) then fission will take place. What happens depends upon the environment. If there is barely enough melted metal to create a critical mass the few million atoms which fission may produce sparks and Cerenkov radiation, that blue glow that surrounds an active fission process, and cause the Uranium to catch fire and burn like Magnesium. Observers reported that when Neutron and X-ray flux was high at Fukashima they also noticed a blue glow in the air above the #3 reactor. On the other hand, if the processes which melted the fuel rods caused such melt to occur sufficiently fast to accumulate more than a critical mass, say melted Uranium flowing down a pipe or tube into a small chamber or plenum, then the confined liquid Uranium will exceed critical mass and a chain reaction will be initiated. On reactor #3 the confinement was sufficient to hold the mass together for a sufficiently long enough time to product the small atomic explosion shown in the video. You will notice that it differs significantly from the explosion at reactor #2, which was caused by Hydrogen gas filling the building. Hydrogen is explosive in air at atmospheric pressure in range from 4% to 74% concentrations. The most it could do is create a shock wave and blow out walls and roofing material, which is all the damage that #2 shows. However, #3 blew concrete several hundred feet into the air, and scattered fuel rod with Uranium and Plutonium up to a mile and a half away!

Ergo, #3 was destroyed by a small nuclear explosion. Perhaps a few milligrams of U-235.

[kubicle]

Re: What "might happen" with the Japanese Nuclear plants?

I'm not sold on nuclear *explosion*, would take more than a few pictures to convince me.

Transient criticality is not out of the question, though (while the hard radiation can be quite fatal to someone close by, it's not an explosion).

http://en.wikipedia.org/wiki/Criticality_accident

[SteveRiley]

Re: What "might happen" with the Japanese Nuclear plants?

Once, several years ago, I read an article (forget where exactly, but from a reputable source) that explained the safety benefits of pebble-bed reactors. Now while nuclear engineering is most definitely outside my bailiwick, I have a decent understanding of physics and better-than-decent of chemistry, so the evidence in the article seemed convincing at the time I read it. Why don't we see these kinds of reactors in use or even being proposed now?

Yup, there's a Wikipedia article. Perhaps the last sentence from the "Criticisms" section sums it up best:

There is significantly less experience with production scale Pebble Bed Reactors than Light Water Reactors. As such, claims made by both proponents and detractors are more theory-based than based on practical experience.

[GreyGeek]

Re: What "might happen" with the Japanese Nuclear plants?

I'm not sold on nuclear *explosion*, would take more than a few pictures to convince me.

Transient criticality is not out of the question, though (while the hard radiation can be quite fatal to someone close by, it's not an explosion).

http://en.wikipedia.org/wiki/Criticality_accident

From your citation:

The only situation where Cherenkov light may contribute a significant amount of light to the blue flash is where the criticality occurs underwater or in solution (such as uranyl nitrate in a reprocessing plant) and this would be visible only if the container were open or transparent.

Previous criticalities, with blue glows and Neutron emissions, were occurring in the spend fuel pond before the final explosion, therefore it is logical to surmise that a final, severe criticality resulted in enough U235 undergoing fission, due to some sort of containment, that an nuclear explosion resulted.

There was, obviously, an explosion of significant size. Compared with videos of explosions in Iraq, I'd estimate that the explosion was equivilent to at least 1 to 2 tons of HE. The candidates for such an event are limited: Hydrogen, some hydrocarbon fuel, a bomb, or a fusion reaction of several milligrams of U235.

Since a Hydrogen explosion usually occurs shortly after the 4% level is reached, especially in an environment where there is criticality sparking taking place, there is usually little more damage than blowing out windows, siding and roofing, but leaving framework intact, along with the visible shock wave. Exactly what is shown in #2. Since there was no accumulation of Hydrogen or hydrocarbon fuels at the bottom of the spent fuel pond, covered by water, which was determined to be the point at which the explosion occurred. The total destruction of the building framework over the pool, the massive crane which was also over the pool, and the pool itself is beyond what a Hydrogen explosion, or even that of, say, 500 gallons of gasoline could do, even it was totally vaporized. The absence of significant orange flames following the explosion cloud into the sky also rules against a hydrocarbon explosion. Unless TEPCO or their government planted explosives the only remaining suspect is a nuclear event. IMO.

Arnie Gundersen explains:

Newly released neutron data from three University of California San Diego scientists confirms Fairewinds' April analysis that the nuclear core at Fukushima Daiichi turned on and off after TEPCO claimed its reactors had been shutdown. This periodic nuclear chain reaction (inadvertent criticality) continued to contaminate the surrounding environment and upper atmosphere with large doses of radioactivity.

In a second area of concern, Fairewinds disagrees the NRC's latest report claiming that all Fukushima spent fuel pools had no problems following the earthquake. In a new revelation, the NRC claims that the plutonium found more than 1 mile offsite actually came from inside the nuclear reactors. If such a statement were true, it indicates that the nuclear power plant containments failed and were breached with debris landing far from the power plants themselves. Such a failure of the containment system certainly necessitates a complete review of all US reactor containment design and industry assurances that containments will hold in radioactivity in the event of a nuclear accident. The evidence Fairewinds reviewed to date continues to support its April analysis that the detonation in the Unit 3 Spent Fuel pool was the cause of plutonium found off site.
...
The first of those was another report that came out last week from California. A group of scientists detected radioactive Sulfur 35 in the atmosphere. It occurred back in March, about two weeks after the Fukushima accident began. The press focussed on the fact that radioactive sulfur was detected in California, but the report held something that was much more important than that, that did not make the news. And that is, how did that sulfur get created? Let's go back across the Pacific to Fukushima. When salt water is hit by neutrons, it creates sulfur. On the nucleus of a sodium atom in salt water hits a neutron, and it becomes a different atom called sulfur. That is the mechanics of it. But what the report showed is that 400 billion neutrons in a square meter were required in order to make the amount of sulfur that was detected in California. That is an enormous number of neutrons. No one asked, where did they come from?

And, I put this quotation separately because if its important implications:

You will recall back on April 26th, I postulated that there was a prompt criticality in the Unit 3 fuel pool and there is a lot of data to support that: the flame was on that side of the building, the height of the explosion. I postulated that that is what deposited the plutonium a mile or two off site. What the Nuclear Regulatory Commission is saying is much worse than that. The Nuclear Regulatory Commission is saying that the reactors have breached, and the containments have breached, and liberated this plutonium, which has gone off site. I do not understand their position. Frankly, I do not think it is right. I still believe that it is the fuel pools that caused the plutonium to be deposited. But if I am wrong and it is not the fuel pools, in fact, the position of the Nuclear Regulatory Commission is much worse. If the reactors have failed and the containments have failed causing this, we really need to seriously look at American reactor design.

[kubicle]

Re: What "might happen" with the Japanese Nuclear plants?

Criticalities produce ionizing radiation which can cause ionized air glow. (It looks like Cherenkov radiation but isn't...Cherenkov radiation can only be seen where the charged particles released from fission can travel faster than light in that medium, which can happen only on mediums where light travels relatively slow like water...but not air). Ionized air glow has been reported on many criticality accidents.

I'm rather skeptical that there would be enough of either to be visible outside the building (especially from a distance). But if there would be, my bet would be that it is not Cherenkov radiation.

The main reason I'm not easily convinced of a nuclear explosion is that it is actually rather hard to get fissile material to explode (just putting a critical mass together won't be enough). It takes a bit of engineering to prevent a critical mass to go sub-critical before there is enough energy released to *explode* (of course one would need to define what constitutes an explosion)...but if we're talking about an explosion strong enough to destroy a building, I just can't think of a way that could happen in the conditions of the reactor (I don't see where the pressure would come to keep any kind of "containment" sealed long enough, for example) or with the fuel used in nuclear plants (it's not enriched enough).

There are also too many variables involved in the two explosions to call the differences visible in explosions definitive evidence of a nuclear explosion.

I'm not saying it's impossible, just that I haven't seen enough evidence to overthrow my skepticism.

Of course, any kind of explosion in a failed nuclear plant is something one does not really want to see (they are not that great on functioning nuclear plants either).

[woodsmoke]

Re: What "might happen" with the Japanese Nuclear plants?

They are putting a "tent" over it? Is that kind of like using a "sock" to......

woodsmoke