Disposing of nuclear weapons production waste is important to national security. Knowing how technetium and other isotopes behave at subsurface storage sites is vital. Previous studies of radionuclide mobility have been limited to after-the-fact destructive sampling of the soil. This study adapted two well-known medical imaging techniques to perform non-destructive analysis. SPECT (single-photon emission computed tomography) imaging revealed non-uniform transport. X-ray computer tomography correlated pores and other structural features.