Because of limited availability of test data with actual Hanford tank-waste samples, a method was developed to estimate expected filtration performance based on physical characterization data for the Hanford Tank Waste Treatment and Immobilization Plant. This method relies upon the similarity between the gel concentration measured during crossflow filtration and the slurry concentration measured after a sample is centrifuged. Testing was performed to determine the centrifuged-solids concentration, and then a subset of simulants was tested to determine the gel concentration during crossflow filtration. These two approaches produced identical results, indicating the centrifuged-solids concentration call be used to represent the gel concentration for filtration. This substitution will allow the expected filtration performance to be characterized at a significantly reduced cost.