THE ROLE OF COLLOIDS IN URANIUM TRANSPORT: A COMPARISON OF NUCLEAR WASTE REPOSITORIES AND ABANDONED URANIUM MINES

The study investigates the role of colloids in the transport of Uranium (U) in geochemical processes under both anoxic and oxic conditions, specifically in the context of nuclear waste repositories and abandoned uranium mines. The objective was to analyze how colloids can either facilitate or impede the transport of radiotoxic U contaminants, depending on their oxidation states (U(IV) and U(VI)). Through experimental simulations that accurately replicate the geochemical conditions expected in these environments, the research found that colloids play dual roles. In nuclear waste repositories, colloids tend to enhance the transport of more insoluble U(IV) species, while in oxic environments associated with abandoned uranium mines, colloids appear to hinder the mobility of dissolved U(VI). These findings highlight the complex interactions between colloidal particles and uranium solubility, and emphasize the importance of considering varying geochemical conditions when assessing the environmental risks associated with uranium transport. The results contribute to a better understanding of contaminant transport mechanisms, essential for managing the environmental impacts of nuclear waste and mining activities.