Expected dose for the nominal scenario class in the 2008 performance assessment for the proposed high-level radioactive waste repository at Yucca Mountain, Nevada

•The nominal (i.e., undisturbed) scenario class in the 2008 Yucca Mountain (YM) performance assessment is described.•Determination of dose and expected (mean) dose to the reasonably maximally exposed individual (RMEI) is described.•Uncertainty in dose to the RMEI is described.•Expected (mean) doses to the RMEI from individual radionuclides and all radionuclides collectively are described.•Numerical stability of the sampling-based procedure used to estimate expected (mean) dose to the RMEI is assessed.

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 the determination of expected (mean) dose to the reasonably maximally exposed individual (RMEI) specified in the NRC regulations for the YM repository for the nominal scenario class (i.e., under nominal or undisturbed conditions) in the 2008 YM PA. The following topics are addressed: (i) properties of the nominal scenario class and the determination of dose and expected (mean) dose to the RMEI, (ii) uncertainty in dose and resultant expected (mean) dose to the RMEI, (iii) expected (mean) dose to the RMEI from individual radionuclides, and (iv) numerical stability of the sampling-based procedure used to estimate the expected (mean) dose to the RMEI. The present paper is part of a special issue of Reliability Engineering and System Safety devoted to the 2008 YM PA; additional papers in the issue describe other aspects of the 2008 YM PA.