Publications Details

INTEGRATED SAFETY AND SECURITY ANALYSIS OF NUCLEAR POWER PLANTS USING DYNAMIC EVENT TREES

Cohn, Brian C.; Haskin, Troy C.; Noel, Todd G.; Cardoni, Jeffrey N.; Osborn, Douglas M.; Aldemir, Tunc

Nuclear security relies on the method of vital area identification (VAI) to inform the sabotage target locations within a nuclear power plant (NPP) that need to be protected. The VAI methodology uses fault trees (FTs) and event trees (ETs) to identify locations in the NPP that contain vital systems, structures, or components. However, the traditional FT/ET process cannot fully capture the dynamics occurring following NPP sabotage or of mitigating actions. A methodology is presented which examines the consequences of sabotage to NPP systems using the dynamic probabilistic risk assessment approach to explore these dynamics. A force-on-force computer code determines the timing and extent of damage to NPP systems and a reactor response code models the effects of this damage on the reactor. These two codes are connected using the novel leading simulator/trailing simulator (LS/TS) methodology. A case study is created using the LS/TS methodology to model an adversary attack on an NPP. This case study models uncertainties in an adversary attack and in the response to determine if reactor core damage would occur, and the time to core damage, as well as the extent of core damage, if damage occurs.