hindsight- how to avoid repeat of Fukushima 4

[davefitz]

In anticipation of the need to incorporate "lessons not quite learned" from the last 3 meltdowns, here is my list economically and technically achievable means to avoid repeats:

a)add a hardwired, remote , backup operating room 0.7 km away from the reactor.
b)spent fuel storage pool located at least 0.5 km away from reactor
c)backup diesel genset at ALL coastal plants to have inlet air snorkel be at least 10 M above sea level. Ditto exhaust discharge nozzle.
d)use geopolymer concrete for containment dome- at least for the foundation- tolerates much higher temperatures than ordinary portland cement concrete.
e) (??) develop and implement a stirling engine based backup circ pump that is driven by primary coolant discharge , air cooled at cold end
f)(??) onsite mandatory storage of sufficient boric acid for loss of coolnat events- perhaps stored in a pressurized local accumulator that can be immeidiately discharged to the core , based on 2 independent keyed switches plus control system confirmation loss of coolant for ( XXX minutes).

 

[davefitz]

coderef:
Chances are the money deposited for the Yucca repository went down the same hole as the excess SS trust funds, excess highway funds from fuel tariffs, etc, and was instead spent on a few bridges to nowhere. I doubt it is sitting in a bank under an account labeled " for Yucca mountain , or equivalent".

 

[CodeRef]

Dave, good point, but I don't think the utilities will just sit back and eat it without a fight. I think some have already filed suit regarding Yucca....and any recommendations resulting from what has occurred in Japan would be costly. I would think the mess of Yucca would be worthy of at least a federal loan gurantee of some type from the government. The question is, who will ask first? Will the government agree? how desperate each one is in speeding up the economic recovery.

FAQ731-376 A question properly stated is a question half solved.

 

[mauner]

I heard a news report that Japan delayed shipment of reprocessed fuel from France because they didn't have enough human resources to monitor the shipment.

Based on this, I'm wondering how much fuel was in the spent fuel pool and how does it compare to US Plants?

It is my understanding that most US Plants are only moving the minimum amount of fuel out of the pool and into dry cask storage to maintain TS required space off loading th fuel from the vessel.

For the U.S., I think regulations need to address the fact that the spent fuel pool was never intended to be a permanent repository.

Furthermore, all fuel that can be placed into dry cask storage should be mandated to be done immediately or hefty penalties be imposed for every day it remains in th SFP, unnecessarily.

 

[rmw]

The storage issue has always been the achilles heel of the Nuclear industry and it is to me an issue that requires a technical solution. That is what we as engineers are all about. Maybe the current crisis will spur that effort along.

rmw

 

[MintJulep]

There is a technical solution in place. Put the spend fuel in dry casks, ship the dry casks to Yuca.

Problem is political.

 

[rmw]

Agreed - however, I think there are still some technical challenges that have to be solved with how to ship it from "here" (wherever the stuff is)to Yucca safely. Or should I say in a form that the public would view as "safely".

The next scenario we don't want to see is a truck or train load of dry casks scattered all over some accident sceen where a truck turns over or a train derails.

The irony is, Nuclear material is shipped all over the country every day, but it is very quietly done and as of now, nothing has happened. But as of a few weeks ago, a Tsunami hadn't inundated a Nuclear station either.

rmw

 

[rcchap]

Dry cask storage is not necessarily the solution.

Current dry casks technologies are not designed for permanent storage, nor are the designed for travel. The dry cask storage is at the plant site, so the fuel is moved only a very short distance. Usually the trucks that do this moving go very slow, and are not designed to travel the highways. Actually, their weight alone would preclude this.

Plants are using dry cask storage because the pools are filling up. Without any storage locations in the pool for spent fuel, the reactor cannot refuel, and thus it could not continue to operate. Thus plants are doing this because they have no choice.

Also, dry cask storage is usually done with the oldest fuel assemblies that put out the least amount of heat. Since the dry casks are cooled with ambient air, recently used assemblies would probably not be stored this way, and they would remain in the pool. The hotter assemblies are the ones that are at greater risk of melting if the SFP water was lost.

On the occasions that they do ship spent fuel, they use special transport casks. These casks are smaller, extremely rugged, and can withstand a collision with a speeding locomotive without rupturing.

The federal government has dropped the ball. Those in Congress who are anti-nukes have made sure that Yucca will never be used, even though billions of dollars of tax payer money had been spent on it and the government had committed to taking the spent fuel (since they actually own it).

I know that Spent Fuel Pools will get a lot of attention in the next few months ... but first we need to understand why the Fukishima pools lost their water. I don't think it was because of the earthquake or the tsunami. I think it was because of the containment design of Fukushima with the pool in very close proximity to the reactor where it could be damaged by the hydrogen explosions. If this does turn out to be the case, then plants who have their pools in a separate building won't have this problem. This is the case for all PWRs in the US.

 

[dicer]

This one is easy. Decommission all of them, world wide, yesterday.

 

[itsmoked]

dicer; Are you for real?

Would you like to live with rotating blackouts for the rest of your, (would-be miserable), life?

Do you prefer a CO2 laden atmosphere? Every creek and river dammed up? A world wide collapse that makes the last one look puny?

And all this because one plant suffered a 9.0 quake and a 10 meter tsunami in the same hour?

Everything that went wrong can be designed out, or retrofitted without any new inventions or unproven technology.

Get a grip.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[cloa]

The technical solution is to hit the nuclear with intense gamma radiation until the elements are transformed from unstable isotopes to stable isotopes- doable with an active nuclear reactor.

 

[owg]

Does decommissioning solve the spent fuel problem?

HAZOP at

http://www.curryhydrocarbons.ca

 

[rmw]

I believe that opinions are like elbows; everyone has a couple and that everyone is entitled to their own st***d opinion.

Unfortunately a large segment of the population of this country agrees with the statement as written by dicer]/b]. Equally unfortunately, they don't have the ability to reason much further than the tip of their nose so they aren't confused with the facts like those that Keith presented.

They go into a dark room, flip the switch and the lights come on. They haven't the foggiest notion of how that comes about. It is kind of like the water in their fawcets, it is always there.

There are quite a number of Nuclear plants in spring outage right now and no one notices because the demand for power is not very high during spring. Let those plants stay off line come June-July-and August and they will notice because it will be rolling blackout time.

I think the country needs a "maintenance outage" week where a whole segment of the industry - Nuclear being just one - goes off line for a week of maintenance during the same week. I think that by the end of that week, the population as a whole would be rethinking their views on the power industry. Especially if it is in late spring or early summer.

As it right now, go try it - go to the nearest light switch and turn it on and see if the light doesn't come on. How neat.

rmw

 

[trottiey]

rmw, that's uncalled for. Nuclear power only supplies 13% of the world's electricity. Keith's predictions of eternal rolling blackouts, every creek and river dammed up, and a world wide collapse are grossly exaggerated. You do no service to your cause by labeling these things "facts," nor by insulting those you disagree with.

 

[electricpete]

I had a feeling this would turn into a nuclear debate. It is natural there will be differences in opinion in all of that.

As events unfold in Japan, I suggest we as engineers should pay attention to quantitative aspects. As bad as it sounds in the media, the amount of exposure to the general public seems to me to have been very small. When we hear that radioactivity from Fukujima is detected in Iowa, it sounds alarming, but we have to remember what a tremendously sensitive ability to detect we have: each decaying isotope gives off a unique signature (gamma energy), so we can tell exactly which isotopes are present. Since some of these isotopes do not occur in nature, the signal to noise ratio is essentially infinite (there is no natural "background" noise for these isotopes). On the other hand, we still are exposed from a variety of natural sources to external and internally-ingested radioactivity which is very similar with respect to biological damage, but does not have identical detection signature.

My feeling is that (unless things turn worse), the biggest impact is that there has been a disruption and psychological burden when the Japanese are at a very vulnerable time and shouldn't have to deal with this. There are also food chain impacts which which at this point remain unknown but will be closely tracked and restricted so that the impact remains economic (not public health).

=====================================
(2B)+(2B)' ?

 

[rmw]

Trottiey,

I don't know what you think "my cause" is. And I am not clear on how I labeled anything as a fact.

I am an adovcate of not only Nuclear Power, but some other very unpopular forms of power generation (e.g. Coal) in today's media hype driven anti any type of power generation climate.

Moreover and more importantly, I am an advocate of the public at large becoming more aware of just where their power comes from and accepting that there are risks with all forms of power generation, and accepting the risks if they want to receive the benefits.

Dicer advocated "decommission them all - yesterday". Whether his comment was tongue-in-cheek to make a point, or he really felt that way doesn't matter. The truth is that a large segment of the population of this country feels just that way.

Kieth "itsmoked" used a little alegory and maybe some overstatement in his response to Dicer but that didn't give me any heartburn, because his point is valid. I agree with him in his call for them to get a grip.

Nuclear Power generates over 20% of the power in this country, higher than the 13% world wide average you quoted, and if all of it were taken off line "yesterday", there would be rolling blackouts for several summers and maybe a few winters to come before it could be replaced with something - who knows what that might be, but it won't be wind and solar.

There is just not enough reserve margin to instantly replace Nuclear Power and still have adequate reserve margin to operate the grid(s) in a stable fashion. And that is a fact. For how long it would remain so is conjecture.

I have witnessed first hand on more than a few occasions right from inside different power station operating rooms the moment when a Nuke somewhere out on their system tripped and watched them scramble to try to deal with catching the load, often unsuccessfully. I can't picture what they would do if all the Nukes on their system tripped simultaneously. You better believe black outs. And that is a fact.

If Dicer is insulted by my opinion, I regret that. That was not my intent. But I would also recommend that he/she not come on an industry specific forum and advocate doing away with that industry if easily insulted. You won't find me on his/her automotive fora advocating doing away with motor vehicles. I think I can accurately guess how I would be responded to if I did.

rmw

 

[msquared48]

Well, here's the clincher to avoiding problems in the future - keep money out of the solution.

Here's the Bloomberg link:

http://www.bloomberg.com/news/2011-...-says-he-covered-up-flaw-at-shut-reactor.html

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[cloa]

If the US nuclear industry is so keen on the safety of their reactors, will they push for the chief regulator to be someone "anti-nuclear"? Not really anti-nuclear rather not nuclear industry friendly like a police man.

 

[polymathjack1234]

http://en.wikipedia.org/wiki/Lead-bismuth_cooled_fast_reactor

So there's no way that lead media(#7 birdshot?) could be pumped in to the reactor to displace all the water?

It seems like you could put a 75ATM boiler on top like an hour glass and then let gravity do the rest.

 

[CodeRef]

All good comments.....
"Failing to plan is planning to fail." - John Wooden

"Although there is no progress without change, not all change is progress." -John Wooden

And my favorite from Warren Buffet.....Beware of geeks bearing formulas.

FAQ731-376 A question properly stated is a question half solved.

 

[mauner]

My point about the spent fuel was that it is safer in dry cask then in a pool with a "tin roof" over it.

The casks are inerted and welded closed. It is my understanding that the dry-cask design was based on the shipping container design done in the 1960's, which can withstand truck, train and plane crashes.

I don't think decay heat is limiting the move, but the amount of radiation when a bundle is removed from the water to be put into the dry cask.

The problem is allowing the SFP to be re-racked to allow more fuel storage and not revising TS to preclude long term storage. Full core off-load should not be the limiting TS requirement based on space.

The Licensee has no motivation to move fuel into a safer onsite storage location. I wonder whether the utilities built a concrete pad sufficient to store all possible fuel or just enough to preclude TS shut down.

Does anyone know what the decommissioning requirements are? I hope its not just leave the fuel in the pool until congress provides a permanent storage location.