The maintenance of the JET reactor leads to the generation of soft housekeeping materials contaminated with tritium and comprising various polymeric materials. Some of the waste falls into the category of intermediate level waste and requires processing. Plasma arc centrifuge and countercurrent regime of gasification have been studied as methods to reduce the mass and volume of the waste. Mass reductions from 8 to 46 have been demonstrated dependent on waste composition. Volume reduction was significantly greater. Analytical procedures for the waste characterization and combustion products have been developed. The wastes and combustion products including chlorine-containing combustion products have been characterized. A formation of water as secondary waste was estimated for countercurrent regime of gasification, which was important for the ultimate processing of tritium-contaminated wastes.