this report deals with the work on: (1) applicability of cotton, woodpulp, sawdust and certain cellulosic derivatives for the removal of tritium from aqueous medium, (2) containment and fixation of tritiated water in nonleachable matrices. the absorption studies on cotton, woodpulp, sawdust, and cellulose acetates were carried out with a view to assess their potentialities as concentration media and also to choose a matrix which can concentrate tritium to the maximum extent possible. the experiments on water hyacinth plants were designed to see the applicability of concentrating tritium and also for providing a via medium for slow release of tritium into the atmosphere. the immobilisation of tritiated water in cement matrices was studied with combinations of portland cement and five filler materials namely sand, silica, vermiculite, portland cement aggregate and accoproof. if cement blocks come in contact with aqueous media as it may happen when the tritium bearing blocks are disposed to the ground, a considerable portion of the contained activity is likely to diffuse and leach out. in order to prevent this, it was proposed to try several coating materials as diffusion barriers over cement blocks. screening of locally available coating materials was done using a diffusion cell. shalismatic hd, anticor and epoxy paint were found to be promising among the screened materials. tritiated cement blocks with 29 vermiculite loading were coated with the above coating materials, and were subjected to leaching, both in sea water and distilled water. the cumulative leaching data for t