In previous work done on Utah's tar sands, it had been shown that the fluidized-bed pyrolysis of the sands to produce a bitumen-derived hydrocarbon liquid was feasible. The research and development work conducted in the small-scale equipment utilized as feed a number of samples from the various tar sand deposits of Utah elsewhere. The results from these studies in yields and quality of products and the operating experience gained strongly suggested that larger scale operation was in order to advance this technology. Accordingly, funding was obtained from the State of Utah through Mineral Leasing Funds administered by the College of Mines and Earth Sciences of the University of Utah to design and build a 4-1/2 inch diameter fluidized-bed pilot plant reactor with the necessary feeding and recovery equipment. This report covers the calibration and testing studies carried out on this equipment. The tests conducted with the Circle Cliffs tar sand ore gave good results. The equipment was found to operate as expected with this lean tar sand (less than 5% bitumen saturation). The hydrocarbon liquid yield with the Circle Cliffs tar sand was found to be greater in the pilot plant than it was in the small unit at comparable conditions. Following this work, the program called for an extensive run to be carried out on tar sands obtained from a large representative tar sand deposit to produce barrel quantities of liquid product. 10 refs., 45 figs., 11 tabs.