PLUTONIUM IN A GRASSLAND ECOSYSTEM 439 



not be changing between environmental plutonium compartments, as previously 

 suggested (Little, 1976), but may indeed be constant. 



Acknowledgments 



Most of the Rocky Flats data presented here were collected by my associates and me in the 

 Department of Radiology and Radiation Biology of Colorado State University while 

 under contract with the Energy Research and Development Administration [now the 

 U. S. Department of Energy (DOE)] . Substantial work was contributed by T. F. Winsor, 

 F. W. Whicker, and J. A. R. Bly. 



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