The development of an adequate data base for assessing the safety of geologic nuclear waste disposal is a vital part of the repository licensing process. This entails understanding both waste form/solution interactions as well as the multiple interaction system of waste form, engineered barriers, and host rock. Although programs are under way to obtain this information, several research areas must be advanced to maximize interpretation of ongoing experiments in a timely fashion. The major areas needed are

  1. waste form and engineered barrier/rock media surface analysis techniques to study structure and composition changes when subjected to anticipated repository conditions
  2. trace level radionuclide chemical species and valence state detection in low and high ionic strength solutions.
In addressing the area of basic research needs, caution must be exercised to pay close attention to the needs of safety assessment modelers and repository design engineers. This is essential so that the direction of basic research and subsequent data collection is responsive to repository licensing needs.