Japan Nuke Plants in a nutshell

First, sorry this took so long.  Work was pretty darn busy all last week and home life is by its nature insane so I just had no time to work on this.  So, let’s get down to business.

The earthquake triggered a shutdown of the plants, which initially went as planned.  The problem was that darned tsunami.  The first thing to note here is that the site was designed to handle a 6.5 meter tsunami.  The one that hit was 7 meters.  Yes, a lousy foot and a half of water is what caused all this mess.  In any case, the tsunami took out at least one of the emergency diesels directly and got the other one either by taking out some power lines or the fuel source.  I don’t have that much detail.  It was at this point that things began to get a little crazy.

Without the diesels , the coolant pumps continued to work off of batteries but after they went out (eight hours if I remember right), the pumps stopped and some important valves failed closed.  That is actually one of the odd things; why on earth would emergency cooling valves fail closed on a loss of power?  Perhaps there was a good reason or perhaps the layout of the plant prevents the establishment of any natural circulation anyway. 

In any case, from here, the water in the core just got hotter and hotter, boiling into steam and increasing pressure in the containment while also reducing the level of liquid in the core itself.  As we know, the pressure was dealt with by releasing the steam into the service floor enclosure.  This would have been fine except that the hydrogen and oxygen in the water had become separated, forming an explosive mixture that went boom.  Now, recall that this is a BWR, with the steam basically coming straight from the core itself.  It was these releases that are responsible for the food and land contamination that you have heard about.

As for the water in the core, the solution as we know has been to keep the core covered with seawater.  Unfortunately, this didn’t happen until the core had been up to ¾ uncovered.  That is very bad, at least for the plant.  Essentially there is no doubt that there was at least a partial core meltdown in at least two plants.  Put simply, they’ll never work again.

Since then, we know that there have controlled on uncontrolled releases of contaminated water into the ocean.  Fortunately, most of the contamination is due to iodine so it will decay quickly.  However, there was so much of it that at least some of the water was 100 Rem on contact (just found that out the other day).  That is HUGE!  You don’t want to be anywhere near that stuff.  It most likely won’t kill you, but it will make you very sick for a very long time.  And if you stay around it to long (say a few hours) it will kill you.  Or turn you into a superhero.  

As for the radiation in general, the area of the site only got up to an average of 12millisieverts or 1.2 Rem/hour with some areas peaking at 400mSv or 40R/hr.  The 40R/hr is bad, don’t walk, run out of that field if you can help it.  The 1.2R/hr general area dose rate is also a lot hotter than anything I have to deal with but it shouldn’t hurt you unless you spend all day in such a field, and even then, it should only make you sick. 

Concerning the way TEPCO has handled things, it would seem to me that for the most part they have done a good job, except in certain instances such as when they claimed that plutonium found on site was left over from old weapons testing.  Also, they apparently don’t play nice with WANO which is a global monitoring agency for nuke plants.  I’m willing to get that that will change or they’ll get out of the nuclear industry all together.  We’ll see. 

Finally, it would seem that they finally have their leak plugged so it should be all uphill from here.

One more thing.  I wanted to just say that the guys who stayed behind to restore emergency power to those plants are nothing short of amazing and should be recognized as the heroes they are.  I read some leaked emails and those guys were working for days even weeks without sleep or food, not knowing what happened to their families in the tsunami.  Please pray for them. 

One last thing.  If you want to see the plant for yourself, you can find it on Google Earth.  Just type in Fukushima, move to the eastern coast, zoom in and scroll south.  When you come to an obviously industrial site that has four primary rectangular buildings in a row, only three of the buildings aren’t so rectangular any more, you’re there.  The destruction that you will see is the result of the hydrogen explosions.