Floating solids drawdown speeds of up-pumping pitched-blade and hydrofoil impellers increase with increasing impeller submergence, with the pitched-blade speed increasing more rapidly than that of the hydrofoil. For submergences greater than 40% of the vessel diameter, performance of the pitched-blade impeller is adversely affected by the discharge flow impinging on the vessel wall rather than the free liquid surface. Drawdown speeds of both impeller types decrease in a similar manner with increasing impeller diameter. For both impeller types, drawdown torque continually increases with increasing impeller diameter, while drawdown power exhibits a minimum at an intermediate impeller to tank diameter ratio; however, power is not a strong function of impeller diameter to tank diameter ratio over the range of this parameter typically used industrially (D/T ranging from 0.2 to 0.5 was studied in this work). Drawdown torque and power of the hydrofoil impeller are lower than those of the pitched-blade impeller, with the differences between the impeller types increasing rapidly with submergence.