Modeled Tritium Migration in Unsaturated-Zone Sediments

Modeled tritium migration in unsaturated-zone sediments from an idealized representation of a radioactive-waste disposal trench. Contours (wavy blue lines) show concentrations in tritium units after 40 years of coupled gas-phase and liquid-phase transport. The new model accounts for waste heating by decay of radioisotopes and organic matter, pressurization by gas generation, and sediment properties that account for preferential transport parallel to sedimentary layering.