This work provides an important confirmation of the strontium/permanganate precipitation process to achieve both acceptable filterability and decontamination for Envelope C (Tanks 241-AN-102 and 241-AN-107) complexant wastes to be treated by the Hanford River Protection Project. This bench-scale demonstration contained a series of seven precipitation batches and crossflow filtration campaigns to decontaminate filtrate of Sr-90 and transuranics from 16.5 L of Tank 241-AN-102 supernatant liquid with entrained solids. Batches were caustic adjusted, strontium and permanganate precipitated, and crossflow filtered with entrained solids using a 2-ft long, 3/8"-internal diameter, 0.1-micron pore size Mott crossflow filter tube. Test ranges for the transmembrane pressures and crossflow velocities were in the range of 30 to 70 psid (2.07 to 4.83 bar) and 9 to 15 ft/s (2.7 to 4.6 m/s), respectively.