Biosolids are the unavoidable and accumulating by-product of the wastewater treatment process and are commonly applied in agricultural settings as a fertiliser and soil amendment. In recent years, growing concerns about the safety risks of land application, combined with a heightened awareness of the potential market value of biosolids, have catalysed a debate on the future of biosolids management in Australia. Two distinct coalitions have emerged: one advocates for the existing management regime of land application, emphasising the serious environmental issues it can help address based on a metabolic imaginary centred on soil, burial and regeneration. The other focuses on a second set of serious concerns and regulatory shifts to propose ways of eliminating biosolids’ dangerous and undesirable elements through technology, burning and transformation. This paper examines the material politics of biosolids management, emphasising the central role played by different elemental properties, forces, and circulations involved in the present conundrum. Empirically, we draw on research with Australian biosolids planners and managers to examine the complex work of trying to sustain or undo existing metabolic relations at the waste-to-resource frontier. Which cycles and circulations are made visible and enabled, which are occluded and disabled, and what happens in the messy middle?