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SUMMARYThe DOE Fuel Cycle Research & Development (FCR&D) Program is developing aqueous and electrochemical approaches to the processing of used nuclear fuel that will generate technetiumbearing waste streams. This report presents Pacific Northwest National Laboratory (PNNL) research in FY10 to evaluate a Fe-based alloy waste form for Tc that provides high waste loading within waste form processing limitations displays long-term retention of radionuclides and can be produced with consistent physical, chemical, and radiological properties for eventual disposal.Fe-Mo metallic waste forms are being considered for the retention and ultimate long-term disposal of Tc from used nuclear fuel recycle. We have conducted microanalysis with scanning electron microscopy (SEM) and transmission electron microscopy (TEM) of non-radioactive Because of the structural and compositional similarity of the intermetallics in the waste form samples, it is concluded that Re is an excellent substitute for Tc in these types of nuclear waste form materials.