Uncertainty and sensitivity analysis for the igneous scenario classes in the 2008 performance assessment for the proposed high-level radioactive waste repository at Yucca Mountain, Nevada

• Uncertainty and sensitivity analysis for the igneous intrusion and igneous eruption scenario classes is described.
• Procedures used: Latin hypercube sampling, stepwise rank regression, and partial rank correlation coefficients.
• Results analyzed: engineered barrier system conditions.
• Results analyzed: radionuclide releases from engineered barrier system, unsaturated zone, and saturated zone.
• Results analyzed: dose and expected dose to the reasonably maximally exposed individual specified by the U.S. NRC.

Extensive work has been carried out by the U.S. Department of Energy (DOE) in the development of a proposed geologic repository at Yucca Mountain (YM), Nevada, for the disposal of high-level radioactive waste. In support of this development and an associated license application to the U.S. Nuclear Regulatory Commission (NRC), the DOE completed an extensive performance assessment (PA) for the proposed YM repository in 2008. This presentation describes uncertainty and sensitivity analysis results for the igneous intrusive scenario class and the igneous eruptive scenario class obtained in the 2008 YM PA. The following topics are addressed for the igneous intrusive scenario class: (i) engineered barrier system conditions, (ii) release results for the engineered barrier system, unsaturated zone, and saturated zone, (iii) dose to the reasonably maximally exposed individual (RMEI) specified in the NRC regulations for the YM repository, and (iv) expected dose to the RMEI. In addition, expected dose to the RMEI for the igneous eruptive scenario class is also considered. The present article is part of a special issue of Reliability Engineering and System Safety devoted to the 2008 YM PA; additional articles in the issue describe other aspects of the 2008 YM PA.