[en] We describe two broad research efforts at Maxey Flats. First, we have completed a study of radionuclide migration and groundwater movement in an experimental study area we constructed adjacent to a waste-filled trench. Second, we are engaged in a major research effort aimed at elucidating the role of organic species in the subsurface migration of radionuclides. We have completed a survey study aimed at mapping the organic content of various groundwater samples from waste trenches and the experimentally study area. We have also begun a detailed chemical speciation study to determine which organics identified in the survey study are compelxed or chelated to radionuclides