Decontamination of caesium and strontium from stainless steel surfaces using hydrogels

Current methods for the decontamination of radioactively contaminated surfaces in nuclear facilities typically rely on the use of liquid agents to remove radio- nuclides. This generates large volumes of highly hazardous liquid waste which must then be treated in costly processes which often require purpose built plant. For the first time we report a nitric acid loaded polymer hydrogel based approach which gives a high decontamination factor for the removal of 137Cs and 90Sr on 304 L grade stainless steel surfaces. The generation of minimal liquid waste and no lateral spread or increased penetration of radionuclides helps mitigate many of the intrinsic hazards of liquid based decontamination methods. Once dried these gels are able to retain the contaminants for treatment as solid waste resulting in a concentrated, less mobile waste form presenting significantly reduced hazards and treatment constraints.