A system and method for removal of uranium and other contaminants from aqueous solution, utilizing live algae, are described. The system includes a bioreactor, in which a reaction mixture of live algae, preferably photosynthetic algae, and contaminated solution are introduced; a means for introducing carbon dioxide gas in the reaction mixture; a means for exposing the reaction mixture to light; means for mixing and impelling the reaction mixture; and means for separating out algae from remediated solution.