Re: Enriched uranium

[Douglas.Minnema@dp.doe.gov]

          Regarding the isotopic composition of enriched uranium, a
          respectable reference would be DOE's Good Practices for
          Uranium Facilities.  As it turns out, there is no one answer
          to the question.  Depending upon the enrichment technique,
          the other isotopes (U-238, U-234, etc) would be in varying
          ratios to the U-235.  Also, much of the enriched uranium
          available today has been recycled, which consequently
          changes the ratios again (and introduces some fission
          product and transuranic contaminants).  The U-234 is the
          main concern activity-wise, and tends to stay with the U-235
          due to similar masses.  However, the U-234 does not fission
          in a reactor, and so when the fuel is recycled the
          U-234/U-235 ratio will increase.

          Doug Minnema, CHP
          Defense Programs, DOE
          <Douglas.Minnema@dp.doe.gov>

          what few thoughts i have truly are my own.