YUCCA MOUNTAIN 2008 PERFORMANCE ASSESSMENT: MODELING DISRUPTIVE EVENTS AND EARLY FAILURES

摘要

The representation of disruptive events (seismic and igneous events) and early failures of waste packages and drip shields in the 2008 total system performance assessment (TSPA) for the proposed high-level radioactive waste repository at Yucca Mountain, Nevada is described. In the context of the 2008 TSPA, disruptive events and early failures are treated as phenomena that occur randomly (e.g., the time of a seismic event) and also have properties that are random (e.g., the peak ground velocity associated with a seismic event). Specifically, the following potential disruptions are considered: (ⅰ) early failure of individual drip shields, (ⅱ) early failure of individual waste packages, (ⅲ) igneous intrusion events that result in the filling of the waste disposal drifts with magma, (ⅳ) volcanic eruption events that result in the dispersal of waste into the atmosphere, (ⅴ) seismic events that damage waste packages and drip shields as a result of strong vibratory ground motion, and (ⅵ) seismic events that damage waste packages and drip shields as a result of shear displacement along a fault. Example annual dose results are shown for the two most risk-significant events: strong seismic ground motion and igneous intrusion.