uptake experiments indicate much lower root uptake discrimination

factors (Pu plant/Pu soil) than those Pu vegetation/soil ratios found
in samples collected from the aged plutonium fallout areas.

There is

need to quantitatively verify the first of these assumptions through
integration of findings from the resuspension and vegetation element
studies.

If it should result that the first assumption indicated

above proves to be groundless,

then the possiblility must be seriously

considered that somehow, the perennial vegetation in these aged
plutonium areas has been concentrating the transuranic elements in
roots and stem tissues in forms that can be rapidly translocated to
each new flush of foliage.

Sampling to verify such a process will be

difficult under field conditions due to cross contamination.

Long-

term root uptake studies now in progress with alfalfa and Atriplex
eaneseens should contribute helpful information on this matter.

FUTURE ACTIVITY PLANS

Efforts shall be directed toward vegetation studies that will contribute information to help resolve those problems of concern mentioned
above. Opportunities will be taken to report findings at scientific
society meetings and symposia and to publish findings in the scientific literature.
Projects involving problems relative to revegetation and restoration
of disturbed arid lands shall be conducted in conjunction with future

cleanup activities in the aged plutonium fallout areas.

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