Reactor Problems in Japan

After the recent quake near Japan and the tsunami that followed have killed thousands, destroyed billions of infrastructure, left many without power or water, destroyed trains, and destroyed oil refineries outright in an inferno worthy of Dresden, we keep hearing about the reactors.

The short answer: yes, it’s a shame. Yes, some people will get some exposure to radiation outside of the plant. Yes, parts of the plant will likely be shut down for good. All in all, the plant suffered an earthquake well in excess of design parameters and has been shut down. The core may slag itself, and some radioactive gases may be vented (and dissipate, and rapidly become non-radioactive ) relative to normal background, but in the end, explosions of the reactor core, or anything like Chernobyl, is just an impossibility.

The long answer is here, from the guys at MIT’s Nuke sciences division.

It is worth mentioning at this point that the nuclear fuel in a reactor can never cause a nuclear explosion like a nuclear bomb. At Chernobyl, the explosion was caused by excessive pressure buildup, hydrogen explosion and rupture of all structures, propelling molten core material into the environment.  Note that Chernobyl did not have a containment structure as a barrier to the environment.

Additionally, Chernobyl was designed so that it got more reactive when it lost water, and the moderating material that made it more reactive was flammable graphite which caught fire.

So please go read the whole thing.