This is a justification for a noncompetitive modification to an existing Indefinite Delivery/Indefinite Quantity (IDIQ) contract. The modification supports continued services from the Center for Nuclear Waste Regulatory Analyses (CNWRA), the NRC’s Federally Funded Research and Development Center (FFRDC). CNWRA provides research and technical assistance to support NRC program offices and others. The work covers both the front and back end of the nuclear fuel cycle. The services are provided free of Organizational Conflict of Interest (OCOI).