The broader impact of this SBIR Phase II project is to demonstrate feasibility and determine the capacity of a novel advanced, high-rate wastewater treatment technology to protect environmental and public health during high-intensity storm events by eliminating sewer overflows and basement backups. Wastewater utilities need reliable, cost-effective, decentralized wastewater treatment as an alternative to expensive long-term plans that emphasize large capital projects. This project will scale and optimize a novel approach to achieve treatment equivalent to conventional methods in less than 35 minutes, compared to the current practice of 8-14 hours. A lower treatment time means a smaller system footprint and, ultimately, cost savings for the utility and ratepayers. The technology will identify sewer overflow hotspots where raw sewage is discharged into receiving bodies of water during storm events as an alternative to basement backups. Implementing this novel solution at overflow locations would alleviate overburdened collection, conveyance, and treatment systems by treating wet weather flows and safely discharging them into waterways. This innovative technology can also be applied at a water reclamation facility to handle overburden or as a mobile unit during disaster relief efforts. This SBIR Phase II project proposes the evaluation of novel concepts including the application of advanced oxidation processes (AOPs) for wastewater treatment, the combination of rapid solid removal technologies with AOPs, and the use of a sustainable waste material and custom cartridge supports with a catalyst for enhanced hydroxyl radical production in catalytic ozonation. None of these approaches have been commercially implemented. The work proposed will demonstrate the ability for advanced technologies to be cost-effectively applied for wastewater treatment, disrupting the standard of partial combined sewer overflow treatment by providing a viable option for rapid wet weather treatment that meets or exceeds Clean Water Act discharge standards. These concepts will be applied at an industry-relevant pilot scale to determine the technical and chemical scaling factors for a full-scale system and to demonstrate required levels of treatment while treating real wastewater. Metrics for success within the research plan include aggressive contaminants of emerging concern removal goals, increased automation and energy efficiency, and a targeted cost ($/gallon treated) analysis to ensure competitive edge in the market. The results of the project will demonstrate that decentralized permit-level treatment is feasible, reliable, and cost-effective, allowing full-scale implementations to begin.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.