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Title: Feasibility study on the verification of fresh fuel assemblies in shipping containers

Abstract

The purpose of this study was to examine the feasibility of using various nondestructive measurement techniques to determine the presence of fuel assemblies inside shipping containers and to examine the feasibility of measuring the fissile content of the containers. Passive and active techniques based on both gamma and neutron assay were examined. In addition, some experiments and calculations were performed to evaluate neutron techniques. Passive counting of the 186 keV gamma from {sup 235}U is recommended for use as an attributes measurement technique. Experiments and studies indicated that a bismuth germanate (BGO) scintillator is the preferred detector. A properly designed system based on this detector will provide a compact detector that can selectively verify fuel assemblies within a shipping container while the container is in a stack of similarly loaded containers. Missing fuel assemblies will be readily detected, but gamma counting of assemblies cannot detect changes in the fissile content of the inner rods in an assembly. If a variables technique is required, it is recommended that more extensive calculations be performed and removal of the outer shipping container be considered. Marking (sealing) of the assemblies with a uniquely identifiable transponder was also considered. This would require the development ofmore » procedures that would assure proper application and removal of the seal. When change to a metal outer container occurs, the technique will no longer be useful unless a radiolucent window is included in the container. 20 refs., 7 figs., 2 tabs.« less

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest Lab., Richland, WA (USA)
Sponsoring Org.:
DOE/EH
OSTI Identifier:
6591602
Alternate Identifier(s):
OSTI ID: 6591602; Legacy ID: DE91001039
Report Number(s):
ISPO-325; PNL--7466
ON: DE91001039
DOE Contract Number:
AC06-76RL01830
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; 98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; FISSILE MATERIALS; MEASURING METHODS; FUEL ASSEMBLIES; VERIFICATION; SPENT FUELS; TRANSPORT; ACCOUNTING; BGO DETECTORS; BWR TYPE REACTORS; CONTAINERS; FEASIBILITY STUDIES; GAMMA FUEL SCANNING; IAEA SAFEGUARDS; NEUTRON DETECTORS; SCINTILLATION COUNTING; SEALS; SPENT FUEL STORAGE; URANIUM 235; ACTINIDE ISOTOPES; ACTINIDE NUCLEI; ALPHA DECAY RADIOISOTOPES; COUNTING TECHNIQUES; ENERGY SOURCES; EVEN-ODD NUCLEI; FISSIONABLE MATERIALS; FUEL SCANNING; FUELS; GAMMA RADIOGRAPHY; HEAVY NUCLEI; INDUSTRIAL RADIOGRAPHY; ISOMERIC TRANSITION ISOTOPES; ISOTOPES; MATERIALS; MEASURING INSTRUMENTS; MINUTES LIVING RADIOISOTOPES; NUCLEAR FUELS; NUCLEI; RADIATION DETECTORS; RADIOISOTOPES; REACTOR MATERIALS; REACTORS; SAFEGUARDS; SCINTILLATION COUNTERS; SOLID SCINTILLATION DETECTORS; STORAGE; URANIUM ISOTOPES; WATER COOLED REACTORS; WATER MODERATED REACTORS; YEARS LIVING RADIOISOTOPES 050900* -- Nuclear Fuels-- Transport, Handling, & Storage; 055001 -- Nuclear Fuels-- Safeguards, Inspection, & Accountability-- Technical Aspects; 210100 -- Power Reactors, Nonbreeding, Light-Water Moderated, Boiling Water Cooled

Citation Formats

Swinth, K.L., and Tanner, J.E. Feasibility study on the verification of fresh fuel assemblies in shipping containers. United States: N. p., 1990. Web. doi:10.2172/6591602.
Swinth, K.L., & Tanner, J.E. Feasibility study on the verification of fresh fuel assemblies in shipping containers. United States. doi:10.2172/6591602.
Swinth, K.L., and Tanner, J.E. Sat . "Feasibility study on the verification of fresh fuel assemblies in shipping containers". United States. doi:10.2172/6591602. https://www.osti.gov/servlets/purl/6591602.
@article{osti_6591602,
title = {Feasibility study on the verification of fresh fuel assemblies in shipping containers},
author = {Swinth, K.L. and Tanner, J.E.},
abstractNote = {The purpose of this study was to examine the feasibility of using various nondestructive measurement techniques to determine the presence of fuel assemblies inside shipping containers and to examine the feasibility of measuring the fissile content of the containers. Passive and active techniques based on both gamma and neutron assay were examined. In addition, some experiments and calculations were performed to evaluate neutron techniques. Passive counting of the 186 keV gamma from {sup 235}U is recommended for use as an attributes measurement technique. Experiments and studies indicated that a bismuth germanate (BGO) scintillator is the preferred detector. A properly designed system based on this detector will provide a compact detector that can selectively verify fuel assemblies within a shipping container while the container is in a stack of similarly loaded containers. Missing fuel assemblies will be readily detected, but gamma counting of assemblies cannot detect changes in the fissile content of the inner rods in an assembly. If a variables technique is required, it is recommended that more extensive calculations be performed and removal of the outer shipping container be considered. Marking (sealing) of the assemblies with a uniquely identifiable transponder was also considered. This would require the development of procedures that would assure proper application and removal of the seal. When change to a metal outer container occurs, the technique will no longer be useful unless a radiolucent window is included in the container. 20 refs., 7 figs., 2 tabs.},
doi = {10.2172/6591602},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Sep 01 00:00:00 EDT 1990},
month = {Sat Sep 01 00:00:00 EDT 1990}
}

Technical Report:

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