The invention relates to a process for treating alkali metals such as sodium charged with tritium or components contaminated with alkali metals such as sodium charged with tritium, in which the alkali metal is reacted with liquid water or water vapor, so as to obtain hydrogen and tritiated hydrogen, characterized in that the hydrogen and the tritiated hydrogen are subjected, in a recombiner (2) to a treatment of catalytic recombination by the addition of oxygen so as to obtain water and tritiated water, and in that the water and the tritiated water are treated so that they are not discharged into the environment.The invention also relates to a plant for carrying out the process.