Background To determine whether current and former construction workers are at
significant risk for occupational illnesses from work at the Department of Energy’s (DOE)
nuclear weapons facilities, screening programs were undertaken at the Hanford Nuclear
Reservation, Oak Ridge Reservation, and the Savannah River Site.

From 1998 to 2004, a series of critical experiments referred to as the fission product (FP) experimental program was performed at the Commissariat à l'Energie Atomique Valduc research facility. The experiments were designed by Institut de Radioprotection et de Sûreté Nucléaire (IRSN) and funded by AREVA NC and IRSN within the French program supporting development of a technical basis for burnup credit validation.

A methodology for performing and applying nuclear criticality safety calculations, for PWR spent nuclear fuel (SNF) packages with actinide-only burnup credit, is described. The changes in the U-234, U-235, U-236, U-238, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, and Am-241 concentration with burnup are used in burnup credit criticality analyses. No credit for fission product neutron absorbers is taken. The methodology consists of five major steps. (1) Validate a computer code system to calculate isotopic concentrations of SNF created during burnup in the reactor core and subsequent decay.

In the 1980s a series of the Haut Taux de Combustion (HTC) critical experiments with fuel pins in a water-moderated lattice was conducted at the Apparatus B experimental facility in Valduc (Commissariat à l'Energie Atomique, France) with the support of the Institut de Radioprotection et de Sûreté Nucléaire and AREVA NC. Four series of experiments were designed to assess profit associated with actinide-only burnup credit in the criticality safety evaluation for fuel handling, pool storage, and spent-fuel cask conditions.

The Nuclear Waste Policy Act of 1982 (the Act), established a
step-by-step process for the siting of the nation's first repository for
high-level radioactive waste and spent fuel. The Act gave the Department of
Energy (DOE) the primary responsibility for conducting this siting process.
The first step in the process laid out in the Act was the development by
the DOE, with the concurrence of the Nuclear Regulatory Commission (NRC), of
general guidelines to be used by the Secretary of the DOE (the Secretary) in

In the 1980s, a series of critical experiments referred to as the Haut Taux de Combustion (HTC)
experiments was conducted by the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) at the
experimental criticality facility in Valduc, France. The plutonium-to- uranium ratio and the isotopic
compositions of both the uranium and plutonium used in the simulated fuel rods were designed to be
similar to what would be found in a typical pressurized-water reactor fuel assembly that initially had an

Background Medical screening programs were begun in 1996 and 1997 at three Department
of Energy (DOE) nuclear weapons facilities (Hanford Nuclear Reservation, Oak
Ridge, and the Savannah River Site) to evaluate whether current and former construction
workers are at significant risk for occupational illnesses. The focus of this report is
pneumoconiosis associated with exposures to asbestos and silica among workers enrolled
in the screening programs through September 30, 2001.

Background Medical screening programs at three Departments of Energy (DOE)
nuclear weapons facilities (Hanford Nuclear Reservation, Oak Ridge, and the Savannah
River Site) have included audiometric testing since approximately 1996. This report
summarizes hearing evaluations through March 31, 2003.
Methods Occupational examinations included a medical history, limited physical
examination, and tests for medical effects from specific hazards, including audiometric
testing. Hearing thresholds by frequency for DOE workers were compared to agestandardized

Background The U.S. Department of Energy (DOE) established medical screening
programs at the Hanford Nuclear Reservation, Oak Ridge Reservation, the Savannah
River Site, and the Amchitka site starting in 1996.Workers participating in these programs
have been followed to determine their vital status and mortality experience through
December 31, 2004.
Methods A cohort of 8,976 former construction workers from Hanford, Savannah River,
Oak Ridge, and Amchitka was followed using the National Death Index through December

The purpose of this engineering calculation is to document the benchmark range, over a variety of parameters, for the validation of the criticality calculations supporting the Monitored Geologic Repository (MGR). This engineering calculation accomplishes this by characterizing the Laboratory Critical Experiments (LCE) and the Pressurized Water Reactor (PWR) Commercial Reactor Criticals (CRC), and summarizing the significant parameters. This engineering calculation supports the Disposal Criticality Analysis Methodology program.

The purpose of this design analysis is to determine the accuracy of the SAS2H module of SCALE 4.3 in predicting isotopic concentrations of spent fuel assemblies. The objective is to develop a methodology for modeling assemblies similar to those evaluated within this analysis and to establish the consistency of SAS2H predictions. The results of this analysis may then be applied to future depletion calculations using SAS2H in which no measurements are available. The analytical model employed for this analysis was the SAS2H module of the SCALE sequence.