Re: Side of a volcano

["Andrew Karam" <akaram@safety.rochester.edu>]

>Siting criteria not being met because of the facility being located on a
>volcano?  Seems like we need to step back and look at the big picture.
>Should that volcano erupt, wouldn't the overall environmental impact
>from the eruption itself far exceed any impact from the destroyed
>(buried?) power plant?  One might even make the same argument for a
>catastrophic earthquake in a populated area, although its impact may not
>be as global.  Maybe the major risk from siting an expensive nuclear
>power plant on a volcano is on the investors only...

At the risk of delving into geology rather than health physics, not
necessarily.  This is reaching back several years to my Volcanology class,
but I think the basics are correct.  It would depend on the type of
eruption and the location of the plant with respect to the eruption.  A
Hawaiian-type eruption (lots of non-viscous lava) would probably just bury
the plant, but a more explosive eruption could launch pretty hefty
projectiles.  Really explosive eruptions (a la Krakatoa) could also throw
pieces of the plant quite a distance if they happened to take place
directly beneath the plant.  A large number of volcanic eruptions originate
in the main crater, but a lot of them also take place in secondary craters,
side fissures, and so forth.  So it's really hard to make any blanket
statement about what we could expect from a volcanic eruption unless we
know the style of the volcanic activity expected from a specific volcano,
the location of the magma chamber and vents with respect to the power
plant, and other, similar factors.  

There are a lot of greenhouse gasses, ozone-depleting gasses, and other
things vented during an eruption (including U, Th, Rn, and K if the lava is
silica-rich).  The amount and type of gas emitted will vary depending on
the type of volcano you have and the eruptive style.  In general, more
explosive eruptions are associated with higher levels of gas dissolved in
the lava.  A lot of the gas is steam, but you get a lot of others, too.
Hawaiian volcanos are pretty well-behaved while Pinatubo threw ash into the
stratosphere.  It's unique for each volcano.  In general, however, I agree
that more people are at risk from lack of electrical power than geologic
concerns, even in close proximity to a volcano.

Andy

Andrew Karam, MS, CHP				
RSO, University of Rochester			  
(716) 275-3781 (voice)						
(716) 256-0365 (fax)
akaram@safety.rochester.edu

"The mind is not a vessel to be filled  but a fire to be lighted" 
 Plutarch
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