Friday, March 18, 2011

Fukushima Nuclear Risk?

I had been looking at for some nuclear incident since Pres. Obama's UN Nuclear Summit in March of 2010. He warned us that the threat of terrorists setting off Co-60 dirty bombs in US cities was our number 1 concern. However, this Fukushima nuclear disaster looks like it could turnn out even worse than any any terrorist dirty bomb. While a few kilogram of C0-60 would cause a lot of local problems, experts say that these Fukushima reactor buildings that blew up were storing up to 660,000 spent nuclear fuel rods.

There is a lot of debate by the media about how bad the Fukushima nuclear disaster is compared with Chernobyl and 3 Mile Island. 3 Mile Island had a partial core meltdown, no containment breach, and only a mild release of radiation by off-gassing of radioactive steam to prevent explosion. While Chernobyl exploded with all control rods extracted, still the total amount of radioactive contamination could not exceed the total mass of the one set of fuel rods in the reactor. What sets Fukushima apart is not whether or not there was containment breach of the core or how much of a meltdown there was or wasn't, but the fact that each of the several nuclear reactors was storing 20 years of used nuclear fuel rods right next to the core. These used fuel rods sitting in storage pools were likely destroyed with the hydrogen explosions and fires we have seen. Consequently, we could be looking at thousands of tons of nuclear fuel being injected into the atmosphere.

What do I suggest to do to protect yourself?
1. Monitor atmospheric nuclear activity: alpha, beta, and gamma radiation. Normal background radiation is between 10-100 counts per minute.
2. Monitor food for nuclear contamination.
3. If significant levels of nuclear contamination occur, applying topical iodine to the skin can protect your thyroid from concentrating radioactive iodine and developing thyroid cancer or damaging your parathyroids.

How much is too much?
Activity = Curie = 1 gm of radium:
Exposure = Roentgen or C/kg,
Absorbed = Rad, Gray = 100 Rad and Rem, Sievert = 100 Rem
Conversion: 1 R = 1 Rad = 1 Rem for gamma and x-radiation
Conversion: Counts per minute (cpm) to Roentgen/hr depends on sensitivity

On this scale an exposure of about 500 R in 5 hours is lethal for humans = 2.5 Gray/Sievert. A typical exposure of normal background radiation for a human is 200 mR per year or 23 μR per hour. Five rem (5000 mrem) is the standard occupational dose limit for one year. The other two accumulated dose limits are for non-lifesaving activities involving critical property protection (10 rem) and lifesaving activities (50 rem). Conference of Radiation Control Program Directors: First Responder's Guide

Average Annual Exposure = 360 mrem/yr
Occupation Annual Exposure Limit = 5000 mrem/yr or 5 R (more for hands)
0.1 mR/hr = 6-33 cpm = background
50 mR/hr = 30-165K cpm = limit
1 R/hr = 600K-3.3M cpm = acute illness

However, there is another risk of all this low level nuclear fallout coming over from Japan. An addition to health risks, the west coast ports will no longer be able to scan cargo from China for nuclear devices. The sensitive plutonium scanners that monitor shipping containers are now saturated with low level Pt from the Fukushima #3 MOX reactor. Pres. George A. Smith of the LDS Church was shown a vision of WW3 and was shown that nuclear devices would be pre-positioned in America before attack and invasion (google: President George A. Smith vision).

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