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The report examines how wastewater treatment plants can be transformed into carbon removal hubs by managing alkalinity and repurposing biosolids. It identifies two primary intervention categories: alkalinity management (including Wastewater Alkalinity Enhancement and Ocean Alkalinity Enhancement) and biosolids management (including biomass burial, biochar, supercritical water oxidation, and incineration with CCS). The document highlights synergies such as the safe destruction of PFAS and the use of existing pumping infrastructure to reduce capital and energy costs. Globally, the biogenic carbon in municipal wastewater represents a theoretical removal potential of 120–460 MtCO2 per year, though current treatment rates limit this to 70–260 MtCO2. Key barriers to scale include feedstock supply chain development, quantification challenges for carbon credits, and ecological risks.