Implementation of a Risk-Informed Monitoring Program for the Saltstone Disposal Facility - 19374

Section 3116(b) of the Ronald W. Reagan National Defense Authorization Act for Fiscal Year 2005 (NDAA) requires the US NRC, in coordination with the appropriate State agency, to monitor certain disposal actions of the US DOE to assess compliance with the performance objectives in Subpart C of Part 61 of Title 10 of the Code of Federal Regulations (CFR). Under Section 3116(b), the US NRC monitors the US DOE disposal of salt waste at the Saltstone Disposal Facility (SDF) at the Savannah River Site (SRS) in South Carolina. Since the first US NRC monitoring plan for the SDF was issued in 2007, the US NRC staff has made the risk-significant areas of interest more specific. Following the US DOE issuance of the 2009 performance assessment for the SDF and the US NRC review of that document, the US NRC issued its second monitoring plan for the SDF in 2013. The 2013 US NRC monitoring plan included 11 monitoring areas, which were broken down into 40 specific monitoring factors. The US NRC prioritized those monitoring factors (i.e., low, medium, high) based on the sensitivity of model results to the assumptions or processes covered by the monitoring factor and the uncertainty in those assumptions or processes. Those monitoring factors can be opened, closed, revised, and re-prioritized based on new information or changes in the US DOE activities and plans. For example, the list of US NRC high-priority monitoring factors has changed in response to changing information. The flexibility of this approach allows the US NRC to remain focused on risk-significant areas of interest. The US NRC staff has made changes to the NDAA monitoring program at the SDF since the issuance of the 2007 monitoring plan. First, the development of more specific monitoring factors and the prioritization of those monitoring factors has been successful in focusing the US NRC and the US DOE resources on risk-significant issues and providing transparency to stakeholders. Second, the US NRC reviews have become more focused on addressing specific monitoring factors, which has made the process for updating the monitoring plan more transparent. Finally, periodic management meetings and monthly telephone calls maintain open communications between the US NRC, US DOE, South Carolina Department of Health and Environmental Control (SCDHEC), and US EPA. (authors)