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Yes, you should be quite safe there.

Gaseous radiation is easily transported by the wind but, other than iodine-131, it is not too dangerous since it does not stay in the body. Fortunately iodine-131 has a 8 day half life so in 80 days it is essentially all gone, thus no really enviromental clean-up is required. On the other hand, radiactive isotopes such as cesium-137 and stronsium - 90 have about 30 year half lifes, so if these are released in quantity ( this has not happened a t fukushima) , then one needs to avoid areas that have been contaminated by them.

In a BWR the water coolant boils in the core and goes through steam turbines to produce electricity. In a PWR this steam is produced in a separate generator. Unfortunately both type of reactors would have been badly damaged by the earthquake and tsunami that hit fukushima since these plants were not designed for events this strong (ie, an 8.2 -design vs 9.0-actual earthquake)

When the spent fuel is transferred to drycast it has normally been cooling in the pool at least 5 years, thus the level of radiaoactivity is relatively low , so air cooling is sufficient to prevent melting. However, in my view it would certainly be best to transport this spent fuel to yucca mountrain for more secure storage.

The way plutonium might be released is if the spent fuel pool fires get hot enough to create aerosol particle containing pliutonium and these were dispersed to the enviroment. So far it appears that nthe authorities in japan are bring the cooling of the spent fuel under control. Anyway, such things were released at chernobyl, but fukushima is a far less energetic accident that there.

It is not likely as long as there is water in the reactor pressure vessels. The only concern that i have is long term cooling using salt water, since after a while the salt may plug up the fuel.  Anyway, if the lower head of the vessels does melt the corium released will interact with the concrete basemat and radioactivity will be released to the environment (not likely in this accident).

My understanding that some well water contamination has been found near the fukushima plants ( it came from the releases todate). I have not heard of any excess radiation in the tokyo water system. Anyway, it no surprise that radiation has found its way into the water near the plants.

This is not my area of expertise, however, i do not believe that these are not very high levels, anyway, best to check the iaea website for levels in water where you should become concerned.

Thorium can be used as a fuel, however the type of concerns associated with the releases during a nuclear emergency (such as that at Fukushima) would be similar.

I hope so. I believe that the safety and security of spent fuel pools has not been seriously addressed, even though most of the problem seen at fukushima were pointed out in a national reserach council report (nrc) published in 1995.

There will likely be reviews of nuclear power safety technology all over the world - and this is a good thing. I hope it does not hurt the construction of new plants s incethey have many new features which improve their safety performance. In contrast, i hope that more attention is paid to the life extension of older plants and to spent fuel pool safety; it is long overdue.

I do not think these particular plants will be used again (certainly not those with salt water in the cores).

If the corium melts through the bottom of the pressure vessel (which is very unlikely since they are submerged in water). It will likely penetrate the mark-i containment , react with concrete basemat and be released to the enviroment. This could be mitigated by filling the contaiment itself with salt water , but this has not yet been done to date.

Japan is a very seismically active country and there are no sites that are immune from such things. Since they really have few domestic fuel sources they need nuclear power . Anyway, they are well aware of the hazards associated seismic events. The big problem was that these plants were designed for 8.2 quakes rather than the 9.0 one that actually occured.

My understanding is that this was tried but they equipment they brought in was not compatible with there systems. If so, this indicates that more detailled disaster planning needs to be done in the future.

We have learned from each nuclear emergency event. The real meassage here is that more detailled emergency planning is needed. Also, in a seismically active region like japan you need to over design your systems (ie, these plants were designed for an 8.2 rather than 9.0 quake and associate tsunami ). Anyway, the cleanup and health-related consequences to the general public will be quite similar to tmi-2

As you may know, all future bwr designs used other pressure suppression contaiment designs. However, the safety concerns that you are referring to had to do with containment loads , not the events that we are seeing at fukushima. Unfortunately, almost any type of contaiment system would have trouble if it were designed for a 8.2 quake and associate tsunami, and got hit by a 9.0 quake.

I suggest you read this piece by the Post: 5 myths about nuclear energy