From: (Brad Davis)
Subject: Fertilizer explosives...
Date: 3 Mar 90 06:20:05 GMT

I talked to my father and this is what he told me.

The mines add 4-6% of the NH4NO3 weight of some fuel oil, often diesel
oil, unless it is an underground charge.  Then they use "corvus" oil
because it doesn't smell.  I don't know what corvus oil really is.

The mines will often use 20 trucks of 25 tons each in a single blast.
That works out to 1.1 million pounds.  The Navajo coal mine
in New Mexico has done 4 times that when moving overburden.

If you use less then 4% oil you get a partial explosion that emits a
yellow or orange smoke.  Greater then 6% and you get black smoke, and
unburnt hydrocarbons.  They try to make a 6% mix but when you are
dealing with a million pounds you can't be exact.

Big holes in Nevada?  Try anywhere in the Mountain West.  

Maybe we should all meet at Navajo the next time they move overburden :-).

Brad Davis