In order to reduce the number of high level waste canisters that will have to be produced by the Hanford Tank Waste Treatment and Immobilization Plant, supplemental waste treatment technologies are being investigated. One such technology is the Near-Tank Treatment System (NTTS), which uses continuous sludge leaching, filtration, and ion exchange to process the waste in a simple, compact system. The NTTS is ideally suited for handling Hanford tanks with large amounts of boehmite, a difficult aluminum phase to dissolve. Processing of boehmite by caustic leaching is the throughput limiter in the NTTS. A model was developed to estimate the capacity of the NTTS based on boehmite kinetics and the contents of the waste tanks considered for processing. Using this model, the lifecycle of the NTTS is estimated to be 11 years. Examples of optimizing NTTS performance are presented using the model. Model results are also compared with recently conducted pilot-scale tests.