O_P_T
Why Be Normal
I'm no nuclear engineer, but I just heard the Japanese Govt. made a statement that there have been readings taken near one of the troubled sites that were 10,000 times the normal background radiation level.
Plus, Fukushima 2 just exploded again. Again, according to them.
Actually, the on-air interpreter called it a "loud noise", so we got that going for us.
EDIT: I'm now hearing that while there is elevated radiation in some of the affected areas in the North, now they are reporting that the amount of that radiation is still less than an X-ray. I don't want to pass that 10,000 times figure on because it doesn't sound like that is accurate.
This is the latest from the NEI
UPDATE AS OF 5:30 P.M. EDT, MONDAY, MARCH 14:
Tokyo Electric Power Co. reported at 3:00 p.m. EDT that work had resumed to pump seawater into Fukushima Daiichi 2 to maintain safe cooling water levels after the utility was able to vent steam from the pressure vessel. The fuel had been exposed for 140 minutes Monday night due to a malfunctioning pressure relief valve. Water levels later went up to cover more than half of the rods.
The U.S. Nuclear Regulatory Commission reports that the Japanese government has formally asked for assistance from the United States on nuclear power plant cooling issues triggered by the March 11 tsunami.
The agency has already sent two experts on boiling water reactor issues to Japan as part of a U.S. Agency for International Development disaster relief team. The experts now are in Tokyo providing technical assistance. The U.S. NRC is also monitoring the Japanese reactor events around the clock from its headquarters operations center in Rockville, Md.
Prior to the second exposure of the rods around 11 p.m., March 14 local time in Japan, radiation at the plant site was detected at a level twice the maximum seen so far – 313 millirem per hour, according to TEPCO.
Chief Cabinet Secretary Yukio Edano said he believes the problem at the plant ''will not develop into a situation similar to Chernobyl,” even in the worst case.
The utility said a hydrogen explosion at the nearby No. 3 reactor that occurred Monday morning may have caused a glitch in the cooling system of the No. 2 reactor.
The hydrogen explosion at reactor 3 on March 14 injured 11 people: seven TEPCO workers at the site and four members of the country’s Self-Defense Forces. The reactor's containment vessel was not damaged and the reactor remains safely contained in its primary containment.
I am skeptical of that 10,000 times background number.
A typical chest x-ray gives you 2 milirem of dose and the typical background radiation in the US is about 300 milirem a year.
So 10,000 times background is a huge amount.
That being said, it could easily be explained by a "fuel flea". This is a term used to describe a small piece of reactor fuel that escapes from a fuel rod and gets out into the plant environment.
These are not uncommon at operating plants. They are really small particles that emit primarily alpha radiation (which is a helium nucleus).
They get out because even during normal plant operation, there is always some small amount of fuel "failure". That is a breaching of the fuel rod integrity.
BTW, I've seen some reports where the term "meltdown" has been equated with fuel failure. Personally I think that definition is far too broad and does not properly express the problems the plant is facing.
Since the core has been uncovered at these units, it is reasonable to assume that there has been some level of fuel failure. So if a flea got out and you did a survey right next to it, you'd get a huge radiation reading.
Does that make it dangerous?
As long as a source of alpha radiation is outside the body, it poses absolutely zero risk.
Pop quiz. What do you need to stop 100% of the radiation from an alpha particle?
A sheet of paper. Since you have dead skin cells thicker than that on the outside of your body, alpha emitting particle pose zero threat unless they get inside the body.
Now if this was a single flea, or even a few fleas, it still doesn't pose a threat to the general public since it can't be easily dispersed to effect multiple people.