Selection of models to calculate the LLW source term

Technical Report · Tue Oct 01 04:00:00 EDT 1991

DOI:https://doi.org/10.2172/6125438· OSTI ID:6125438

Sullivan, T M ^[1]

---

1. Brookhaven National Lab., Upton, NY (United States)

Performance assessment of a LLW disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the source term). The focus of this work is to develop a methodology for calculating the source term. In general, the source term is influenced by the radionuclide inventory, the wasteforms and containers used to dispose of the inventory, and the physical processes that lead to release from the facility (fluid flow, container degradation, wasteform leaching, and radionuclide transport). In turn, many of these physical processes are influenced by the design of the disposal facility (e.g., infiltration of water). The complexity of the problem and the absence of appropriate data prevent development of an entirely mechanistic representation of radionuclide release from a disposal facility. Typically, a number of assumptions, based on knowledge of the disposal system, are used to simplify the problem. This document provides a brief overview of disposal practices and reviews existing source term models as background for selecting appropriate models for estimating the source term. The selection rationale and the mathematical details of the models are presented. Finally, guidance is presented for combining the inventory data with appropriate mechanisms describing release from the disposal facility. 44 refs., 6 figs., 1 tab.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (United States). Div. of Low-Level Waste Management and Decommissioning; Brookhaven National Lab., Upton, NY (United States)
• Sponsoring Organization: NRC; Nuclear Regulatory Commission, Washington, DC (United States)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6125438
• Report Number(s): NUREG/CR-5773; BNL-NUREG--52295; ON: TI92000969
• Country of Publication: United States
• Language: English

Related Subjects

052002* -- Nuclear Fuels-- Waste Disposal & Storage
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
B CODES
CALCULATION METHODS
COMPUTER CODES
CONTAINERS
DISSOLUTION
ENVIRONMENTAL TRANSPORT
FAILURES
FLUID FLOW
ISOTOPES
LEACHING
LOW-LEVEL RADIOACTIVE WASTES
MANAGEMENT
MASS TRANSFER
MATERIALS
MATHEMATICAL MODELS
NUCLEAR FACILITIES
P CODES
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE FACILITIES
RADIOACTIVE WASTE MANAGEMENT
RADIOACTIVE WASTES
RADIOISOTOPES
RADIONUCLIDE MIGRATION
SEPARATION PROCESSES
SOURCE TERMS
WASTE DISPOSAL
WASTE FORMS
WASTE MANAGEMENT
WASTES