SOLUTE TRANSPORT IN HETEROGENEOUS MEDIA - A DISCUSSION OF TECHNICAL ISSUES COUPLING SITE CHARACTERIZATION AND PREDICTIVE ASSESSMENT

Long-term predictive evaluation of solute transport and transformation in geologic media is a critical element in the performance assessment of nuclear waste geologic repositories and in the environmental resto ration or control of contaminated sites that is facing many countries today. Since the geologic media are heterogeneous and their details ca n never be known deterministically, longterm prediction of flow and tr ansport in such systems requires new thinking. Thus, it is no longer p ossible to consider site characterization and predictive modeling calc ulations to be separate activities; rather they are highly coupled. Th is paper presents a discussion of the coupling and proposes a framewor k of technical issues that need to be studied.