The migration behaviour of the tri- and tetravalent actinides Am and Pu was strongly mediated by the bentonite colloids and recovery increased from 20-30 % in the absence of bentonite colloids, to about 60-80 % in the presence of bentonite colloids.

Batch experiments and the high content of Am and Pu bound to the added bentonite colloids in the injection cocktail clearly display uptake of at least these elements on the bentonite colloids. The breakthrough curves below show that the colloids, the tri- and tetravalent actinides and the Cs arrived slightly earlier than the "conservative" solute.