U.S. efforts to site and construct a deep geologic repository for used fuel and high level
radioactive waste (HLW) proceeded in fits and starts over a three decade period from the late
1950s until 1982, when the U.S. Congress enacted the Nuclear Waste Policy Act (NWPA). This
legislation codified a national approach for developing a deep geologic repository. Amendment
of the NWPA in 1987 resulted in a number of dramatic changes in direction for the U.S.
program, most notably the selection of Yucca Mountain as the only site of the three remaining

U.S. efforts to site and construct a deep geologic repository for used fuel and high level radioactive waste (HLW) proceeded in fits and starts over a three decade period from the late 1950s until 1982, when the U.S. Congress enacted the Nuclear Waste Policy Act (NWPA). This legislation codified a national approach for developing a deep geologic repository. Amendment of the NWPA in 1987 resulted in a number of dramatic changes in direction for the U.S. program, most notably the selection of Yucca Mountain as the only site of the three remaining candidates for continued investigation.

The effective termination of the Yucca Mountain program by the U.S. Administration in 2009
has left the U.S. program for management of used fuel and high level radioactive waste (HLW)
in a state of uncertainty. In concert with this major policy reset and in response to the resulting
policy vacuum, the President directed the Energy Secretary to establish the Blue Ribbon
Commission on America’s Nuclear Future (BRC) “…to conduct a comprehensive review of
policies for managing the back end of the nuclear fuel cycle and to provide recommendations for

Since 1989, EPRI has been conducting independent assessments of the proposed deep geologic repository for the disposal of spent nuclear fuel and high level radioactive waste at Yucca Mountain, Nevada. EPRI pioneered application of the total system performance assessment (TSPA) approach for evaluating performance of geologic repository systems on a probabilistic basis. Along the way, EPRI developed the Integrated Multiple Assumptions and Release Code (IMARC) as its primary analytical tool for TSPA-based evaluations.

Since 1989, EPRI has been conducting independent assessments of the proposed deep geologic repository for the disposal of spent nuclear fuel (SNF) and high level radioactive waste (HLW) at Yucca Mountain, Nevada. EPRI pioneered application of the total system performance assessment (TSPA) approach for evaluating performance of geologic repository systems on a probabilistic basis. Along the way, EPRI developed the Integrated Multiple Assumptions and Release Code (IMARC) as its primary analytical tool for TSPA-based evaluations.

The effective termination of the Yucca Mountain program by the U.S. Administration in 2009 has further delayed the construction and operation of a permanent disposal facility for used fuel and high level radioactive waste (HLW) in the United States. In concert with this decision, the President directed the Energy Secretary to establish the Blue Ribbon Commission on America's Nuclear Future to review and provide recommendations on options for managing used fuel and HLW.

The table is based on historical costs through 2006, which are shaded, and projected costs in the 2008 TSLCC. To convert to 2010$, multiply by 1.0586. The 2008 TSLCC assumes a single repository system capable of accepting and disposing of SNF and HLW equivalent to 122,100 Metric Tons of Heavy Metal (MTHM). This estimate includes all defense wastes currently destined for disposal at Yucca Mountain and projected discharges of SNF from commercial utilities, including the 47 nuclear power reactors that had received license extensions from the NRC as of January 2007.

Fuel from the Fast Flux Test Facility ' (FFTF) has been considered for disposal at the proposed

Disposal Criticality Analysis Methodology Topical Report describes a methodology for performing postclosure criticality analyses within the repository at Yucca Mountain, Nevada. An important component of the postclosure criticality analysis is the calculation of conservative isotopic concentrations for spent nuclear fuel. This report documents the isotopic calculation methodology. The isotopic calculation methodology is shown to be conservative based upon current data for pressurized water reactor and boiling water reactor spent nuclear fuel.

The objective of this calculation is to evaluate the required minimum burnup as a function of initial boiling water reactor (BWR) assembly enrichment that would permit loading of spent nuclear fuel into the 44 BWR waste package configuration as provided in Attachment IV. This calculation is an application of the methodology presented in ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003). The scope of this calculation covers a range of enrichments from 0 through 5.0 weight percent (wt%) U-235, and a burnup range of 0 through 40 GWd/MTU.