The objective of this study was to develop or identify flow correlations for predicting the flow parameters needed for the design and operation of slurry pipeline systems for transporting radioactive waste of the type stored in the Hanford single-shell tanks and the type stored at the Oak Ridge National Laboratory (ORNL). This was done by studying the flow characteristics of simulated waste with rheological properties similar to those of the actual waste. Chemical simulants with rheological properties similar to those of the waste stored in the Hanford single-shell tanks were developed by Pacific Northwest Laboratories, and simulated waste with properties similar to those of ORNL waste was developed at ORNL for use in the tests. Rheological properties and flow characteristics of the simulated slurry were studied in a test loop in which the slurry was circulated through three pipeline viscometers (constructed of 1/2-, 3/4-, and 1-in. schedule 40 pipe) at flow rates up to 35 gal/min. Runs were made with ORNL simulated waste at 54 wt % to 65 wt % total solids and temperatures of 25{degree}C and 55{degree}C. Grinding was done prior to one run to study the effect of reduced particle size. Runs were made with simulated Hanfordmore » single-shell tank waste at approximately 43 wt % total solids and at temperatures of 25{degree}C and 50{degree}C. The rheology of simulated Hanford and ORNL waste supernatant liquid was also measured.« less