Several conclusions appear self-evident concerning the use of radioactive 

 tracers to follow the movement of natural sediments. It appears that the 

 addition of radioactive tracers will be an invaluable tool to determine or make 

 possible measurements which heretofore have been impossible or extremely 

 difficult. The use of glass to simulate the natural sediment appears quite 

 feasible and the use of sodium, lanthanum or gold for respectively tests of 1, 

 2 and 3 weeks is feasible. Finally, the experience and knowledge of techniques 

 gained from laboratory testing will be of invaluable assistance for future field 

 operations. 



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