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From: mwg@petrus.UUCP (Mark Garrett)
Newsgroups: net.sci
Subject: Re: Request for info . . . "graphite fire"
Message-ID: <119@petrus.UUCP>
Date: Wed, 7-May-86 10:24:39 EDT
Article-I.D.: petrus.119
Posted: Wed May  7 10:24:39 1986
Date-Received: Sat, 10-May-86 23:30:27 EDT
References: <142@mcc-hi.UUCP> <1144@psivax.UUCP>
Organization: Bell Communications Research, Inc
Lines: 46

++
C'mon guys, let's get real about some things:

>         To start with, "nuclear fire" is just a meaningless buzz
> phrase coined by the media. A graphite fire is just an ordinary fire
> in the form of carbon known as graphite...

I wouldn't call it meaningless.  The news uses the term "nuclear fire"
to emphasize that the fire is not ordinary.  It has a radioactive pile
as its source of heat, which means that it is VERY HOT, and will continue
to get hotter until it melts down and spreads out, increasing its surface
area enough to dissipate the heat it is generating.  It also means that
everything about it (smoke, steam, residue and the general area) is
highly contaminated.

> 	Being essentially pure carbon, graphite
> burns *very* well when oxygen is present.

Graphite doesn't burn at temperatures lower than a couple thousand degrees
(C or F, I'm not sure).

> ... Also, the fire may have been hot enough to evaporate water.

Any fire that isn't hot enough to evaporate water isn't worth worrying
about.

> In fact the toxic effect of heavy metals resemble those of radiation.

There are two aspects of Plutonium toxicity (as far as I understand).
As a chemical, Plutonium Oxide is deadly in minute quantities in a very
short time.  As a radiation source Plutonium (with or without oxide)
will give you radiation sickness which is longer term (days to years),
involving all kinds of things (not just chemical poisoning).  I don't
think lead poisoning has the same multiplicity of effects.

> ...(Actually, the Russians may have used a local lake
> in fighting the fire and cooling the reactor, so the water may be
> contaminated anyway, without a complete meltdown)

They used wet sand to smother the fire (it's not clear if it's even out
yet).  Water would result in a lot of radioactive steam and possibly
a hydrogen explosion (as someone pointed out in a previous posting).

>                                 Sarima (Stanley Friesen)

-Mark Garrett