Shipping question

[Keith Welch <welch@jlab.org>]

Group,

Several questions regarding shipping very small quantity of U234/U235.  I
have a small electroplated disc source with about 50 pCi activity.  I don't
know the enrichment or ratio of isotopes.  The disc weighs about 3g.  I
don't know the mass of the actual material deposition.  Now...

1. 49CFR says if it's less than .002 uCi/g it's not RAM.  Am I allowed to
use the total weight of the disc?  The rule says it has to be "essentially
uniformly distributed" in the material.  Does this configuration qualify
for uniformly distributed?  AND...

2.  The definition of fissile material is not based on a quantity.  So by
definition if there is ANY U235 in it, it would appear to be fissile.
However, there are excepted quantities (15 grams seems to apply here).
Now, this appears to give me no choice but to call it either fissile or
fissile exempt.  

So:  Which definition drives the classification of the material?  Assuming
I can say it's uniformly distributed, do I claim it's not RAM, and stop
there? or do I still have to consider the fact that it contains U235 and
call it fissile exempt since there seems to be no "deminimus" exclusion
that lets you say it's not RAM if it contains U235.

Stated briefly: Can something be below the threshold for classifying as
RAM, yet still have to be classed as fissile exempt?




Keith Welch
Thomas Jefferson National Accelerator Facility
Newport News VA
welch@cebaf.gov
Ph: (757)269-7212
FAX:(757)269-5048
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