Utilization of burnup credit in criticality safety analysis for long-term disposal of spent
nuclear fuel allows improved design efficiency and reduced cost due to the large mass of fissile
material that will be present in the repository. Burnup-credit calculations are based on depletion
calculations that provide a conservative estimate of spent fuel contents (in terms of criticality
potential), followed by criticality calculations to assess the value of the effective neutron

Burnup credit (BUC) is a concept applied in the criticality safety analysis of spent nuclear fuel
in which credit or partial credit is taken for the reduced reactivity worth of the fuel due to both fissile
depletion and the buildup of actinides and fission products that act as net neutron absorbers.
Typically, a two-step process is applied in BUC analysis: first, depletion calculations are performed
to estimate the isotopic content of spent fuel based on its burnup history; second, three-dimensional

This report is part of a report series designed to document benchmark-quality radiochemical assay data
against which computer code predictions of isotopic composition for spent nuclear fuel can be validated
to establish the uncertainty and bias associated with the code predictions. The experimental data analyzed
in the present report were acquired from two international programs: (1) ARIANE and (2) REBUS, both
coordinated by Belgonucleaire. All measurements include extensive actinide and fission product data of

The Construction Industry Research and Policy Center (CIRPC) at the University of Tennessee was awarded a contract by the Center to Protect Workers’ Rights, under their grant program with the National Institute of Occupational Safety and Health (NIOSH), to analyze injuries of employees of the U. S. Department of Energy (DOE) and their contractors’ working at DOE work sites. The injury data analyzed were injuries recorded in DOE’s Computerized Accident Incident Reporting System (CAIRS).

Fundamentally, a nuclear energy system uses nuclear fission to create heat, which is then available for generating electricity or other applications, including seawater desalination, heating, and production of other fuels. The nuclear energy system as currently deployed in the United States, Figure 1, consists of a number of integrated components, beginning with the natural resources required for nuclear fuel, followed by fissioning of the fuel in reactors connected to electricity generation facilities, and ending with the disposition of all wastes, including used nuclear fuel (UNF).

The purpose of this document is to describe the Monitored Retrievable Storage (MRS) Project and to establish approved cost and schedule baselines against which overall progress and management effectiveness shall be measured. For the sake of brevity, this Project Plan will be referred to as the Plan throughout this document.

The characteristics of spent nuclear fuel and high-level waste are described, and options for permanent disposal that have been considered are described. These include:
•disposal in a mined geological formation,
•disposal in a multinational repository, perhaps on an unoccupied island,
•by in situ melting, perhaps in underground nuclear test cavities,
•sub-seabed disposal,
•disposal in deep boreholes,
•disposal by melting through ice sheets or permafrost,
•disposal by sending the wastes into space, and

This paper provides a brief description of the United States Nuclear Regulatory Commission (NRC) and its regulatory process for the current nuclear fuel cycle for light water power reactors (LWRs). It focuses on the regulatory framework for the licensing of facilities in the fuel cycle. The first part of the paper provides an overview of the NRC and its regulatory program including a description of its organization, function, authority, and responsibilities.

This Record of Decision has been prepared pursuant to the Regulations of
the council on Environmental Quality, 40 CFR Part 1805, on the selection of a
strategy for the disposal of commercially-generated radioactive wastes and the
supporting program of research and development.
The United States Department of Energy has decided to (1) adopt a strategy to
develop mined geologic repositories for disposal of commercially-generated
high-level and transuranic radioactive wastes (while continuing to examine

This paper draws on my experience as a reviewer of the scientific programs and performance assessments of the geological repository for transuranic waste at the Waste Isolation Pilot Plant in New Mexico and the proposed repository for spent nuclear fuel and high-level waste at Yucca Mountain in Nevada. In addition, I have served on numerous committees of the National Research Council that have addressed many aspects of nuclear waste management.