Probabilistic Risk Assessment

Energy Research, Inc. has been involved in the performance and regulatory review of numerous probabilistic risk/safety assessment (PRA/PSA) studies over the last 25 years. These include performance of regulatory PSAs for all Swiss and all Spanish nuclear power plants, performance of Level-2 PSAs for three nuclear power plants in Germany (including a seismic PSA), and U.S. Nuclear Regulatory Commission -sponsored regulatory review of more than 30 Individual Plant Examinations (IPEs) and Individual Plant Examinations for External Events (IPEEEs) for U.S. nuclear power plants. In addition, Energy Research, Inc. has been participating in the review of PRAs for US EPR, US APWR, ABWR, and ESBWR for U.S. Nuclear Regulatory Commission.

Recently, a plant-specific Level-2 PSA for low power, shutdown and refueling modes was completed for a BWR with MARK I containment. Energy Research, Inc. has been involved in the performance of PRA success criteria analyses for U.S. Nuclear Regulatory Commission and the Swiss Nuclear Safety Inspectorate, using
plant-specific MELCOR input models that have been developed by Energy Research, Inc. In addition, ADAM System analyses are also performed for assessment of licensee submittals for the Swiss Nuclear Safety Inspectorate.

Energy Research, Inc. was recently awarded two contracts to support the NRC in developing a full-scope site Level 3 PRA that assesses accidents involving one or more reactor cores, as well as other site radiological sources (i.e., spent fuel pools and dry storage casks). The insights gained from a full-scope site Level 3 PRA project are expected to further enhance regulatory decision-making and to help focus resources on issues most directly related to the mission of the NRC to protect public health and safety.

In addition, Energy Research, Inc. is involved in a NRC project to provide on-demand calculation, consultation and model development support for a range of Office of Research initiatives related to PRA success criteria. ERI has supported changes to the Byron input deck, performance of an uncertainty study for comparison to EPRI MAAP analyses, performance of plan-specific success criteria calculations (e.g., Surry, Peach Bottom, etc.), and support for emerging issues as required by NRC.