616 TRANSURANIC ELEMENTS IN THE ENVIRONMENT 



200 



— Total Plutonium (particulate and dissolved) 



120 



^30 



z 



Lu 20 

 o 

 cc 



!^ 10 





 20 



10 





 20 



10 



o 

 cc 



(J 

 cc 







H 60 



-z. 



LU 



o 40 



cc 



UJ 



°- 20 

 



Loss on 

 ignition 

 (organic) 



Calcium 

 carbonate 



J I \ \ L 



J \ \ \ \ L 



Terrigenic 

 (by difference) 



J \ \ L_L 



M A M J J AS 

 MONTH (1975) 



N 



Fig. 10 Total (particulate and dissolved) piutonium and principal constituents of 

 particulate material from filtration (ANL-5, 7 m above bottom). 



November to December. The excellent correlation between total plut-onium and the 

 combination of Si02 and CaCOa is shown in Fig. 11. To the extent that a sample of 

 particles and water constitute a closed system, it is the total piutonium that should 

 correlate with this combination of variables if piutonium is primarily derived from the 

 dissolution of either siUca or calcite particles. 



Regeneration of piutonium in the water column would thus appear to result from the 

 dissolution of calcite and silica, especially during November and December. The role that 

 resuspension plays in this event is uncertain. It has been suggested (Wahlgren et al., 1976) 

 that resuspension of bottom sediments and redistribution of piutonium between particles 

 and water must occur to account for the reappearance of piutonium in surface waters and 

 for the apparent plateau leveling-off of average piutonium concentrations in the lake from 



