The Savannah River Plant (SRP) has about 30 million gallons of high-level, radioactive, liquid waste stored in large waste tanks. This waste is a by-product of the production of nuclear defense materials at SRP. Plans are to build the Defense Waste Processing Facility (DWPF) at SRP to convert this waste into solid form. A key step in the planned DWPF process is the vitrification or glassmaking step, in which the radionuclides are incorporated in borosilicate glass. Two types of glass melters have been developed for this step. The planned melter design for the DWPF is a slurry-fed, continuous, joule-heated melter. The backup melter design is an in-can melter. Previous plans were to dry and partially calcine the radioactive waste sludge before feeding it to the in-can melter. However, it was desirable to eliminate the drying step and feed the waste sludge as a liquid. Eliminating the drying step simplified the process and reduced the project cost. At the Savannah River Laboratory (SRL), a full-scale in-can melter of the former dry-fed design was converted to slurry feeding by adding appropriate feed and off-gas systems. Five experimental runs were made with this process from August to December 1981. The purpose of this program was to demonstrate the basic process, determine key process variables such as rate and off-gas system requirements, and identify potential problems with long-term operation. A full-scale, nonradioactive process has been studied in which a slurry of waste sludge and glass formers is fed to a heated can. Saturated steam is used to cool the off-gas. Initial results show the concept to be technically adequate.