See:
http://www.washingtonpost.com/business/economy/nuclear-crisis-deepens-
as-third-reactor-loses-cooling-capacity/2011/03/14/ABk6rQV_story.html
http://tinyurl.com/67tp62y
"A commercial satellite photo of the complex showed piles of debris
on top of units 1 and 3, which raised new fears about the condition
of the pools where spent fuel is stored, especially at unit 1, where
a design by General Electric placed the pool on top of the reactor
but below the outer structure that was destroyed. The ability of
workers to assess the damage was hindered by fears that another
explosion might occur."
"In March 2010, 1,760 tons of spent fuel was stored in the six pools
— 84 percent of capacity, according to Tokyo Electric."
That is over 250,000 kg of uranium (plus plutonium in the case of
MOX) per pool on average. What is that going to do if it melts into
a blob and starts boring a hole into the earth? That's a rhetorical
question. Google (China syndrome).
That 250,000 kg is many times the fissionable material in an atom
bomb. A big problem even if it is mostly U238. MOX fuel, used in
unit 3, is a *huge* problem. Plutonium is one of the most
radiologically poisonous materials on earth. Pu242 has a half-life
of 376,000 years. The atomic bomb Little Boy, dropped on Hiroshima,
had 64 kg of uranium. Fat Man, dropped on Nagasaki, contained 6.2 kg
of plutonium.
Material that melts down inside the reactor steel containment has a
chance of cooling down, due to the presence of moderator material,
which should end up in the mess along with the fuel glob. However,
spent fuel storage does not include moderator rods.
Lesson learned too late: don't store fuel rods near reactors that
have to be cooled and might explode. Second lesson: MOX fuels are a
very bad idea in commercial power reactors.
"According to information on the website of Tokyo Electric Power Co.,
which operates the Fukushima facility, more than 200 tons of spent
fuel is stored [away from the reactors] in casks." See:
http://www.propublica.org/article/status-of-spent-nuclear-fuel-in-
question-at-crippled-japanese-power-plant
http://tinyurl.com/4taefqa
The above site has a good satellite photo taken before Fukushima No 2
blew. There are many amateur model airplane and drone builders that
could get much closer much higher resolution photos. What is really
needed are little robots to explore inside. The US Navy should be
able to provide some help along those lines.
The Fukushima reactors typically are loaded with 56 to 91 tons of
fuel. See table on page 1 (called page 70) of:
http://www.tepco.co.jp/en/challenge/energy/pdf-1/nuclear-e.pdf
If the fuel loaded into reactor 3 is 0.5% plutonium, then that is
about 280 kg of plutonium, about 45 times that in the Fat Man bomb.
If a China SYndrome develops, then huge amounts of soil material can
become neutron activated, so many more tons of toxic material could
end up in the environment.
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
