For his innovation in the production and application of medical isotopes; for advancing the separation and purification of actinides and heavy elements; and for his leadership in the use of alpha emitters to save the lives of cancer patients.
For his broad scientific contributions and international reputation in aqueous chemistry and geochemistry; for his research into the structure, dynamics, and reactions at fluid–solid interfaces; and for his leadership and service to ORNL and the international scientific community.
For pioneering research in disturbance and landscape ecology and in modeling of land-use change with its implications for global changes, which have influenced environmental decision making on a worldwide scale.
For forefront studies of the fundamental science of actinide elements, through mendelevium, which employ novel experimental techniques, make systematic comparisons, and emphasize the role of the elements' electronic configurations.
For distinguished research on the air/surface exchange of atmospheric trace gases and particles and their interactions with the Earth's biogeochemical cycles, and for pioneering developments in atmospheric sampling methodologies with special emphasis on the global mercury cycle.