Further Aspects of Recycled Uranium

[Rodney Bauman <rodney_bauman@wssrap-host.wssrap.com>]

Keith and the RadSafe Community,

Your calculations are correct.  One word of caution: when using DAC values for
your comparison, be sure to state your source.  Differences exist between
10CFR20 and 10CFR835 for the isotopes Pu-239, Pu-240 and Am-241.

However, 1 ppm of Pu-239 is an amount much greater than expected for most
streams of "recycled" uranium.  Standards in existence since the early 1950s
limited Pu-239 activity to approximately 10 ppb of uranium.  This specification
had to be met prior to reduction of the uranium in solution to solid UO3 at the
reprocessing site.  Most data show levels to be much less than this limit.  For
"natural" UO3 (i.e., approx. 0.71% U-235 by weight), 10 ppb equates to just over
10% additional inhalation burden (using current 10CFR835 DAC values).

Certain processes at the gaseous diffusion plant sites concentrated the
transuranic content into "waste" streams.  The most obvious is the fly ash
produced during the fluorination of UF4 to UF6 in the GDPs' feed plants.

Rodney Bauman, CHP, RRPT
rodney_bauman@wssrap-host.wssrap.com


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