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Title: Criticality assessment of LLRWDF closure

Abstract

During the operation of the Low Level Radioactive Waste Disposal Facility (LLRWDF), large amounts (greater than 100 kg) of enriched uranium (EU) were buried. This EU came primarily from the closing and decontamination of the Naval Fuels Facility in the time period from 1987--1989. Waste Management Operations (WMO) procedures were used to keep the EU boxes separated to prevent possible criticality during normal operation. Closure of the LLRWDF is currently being planned, and waste stabilization by Dynamic Compaction (DC) is proposed. Dynamic compaction will crush the containers in the LLRWDF and result in changes in their geometry. Research of the LLRWDF operations and record keeping practices have shown that the EU contents of trenches are known, but details of the arrangement of the contents cannot be proven. Reviews of the trench contents, combined with analysis of potential critical configurations, revealed that some portions of the LLRWDF can be expected to be free of criticality concerns while other sections have credible probabilities for the assembly of a critical mass, even in the uncompacted configuration. This will have an impact on the closure options and which trenches can be compacted.

Authors:
; ;
Publication Date:
Research Org.:
Westinghouse Savannah River Co., Aiken, SC (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
10125630
Report Number(s):
WSRC-RP-92-974
ON: DE93006887
DOE Contract Number:
AC09-89SR18035
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 6 Oct 1992
Country of Publication:
United States
Language:
English
Subject:
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; LOW-LEVEL RADIOACTIVE WASTES; GROUND DISPOSAL; COMPACTING; SAVANNAH RIVER PLANT; URANIUM; DECONTAMINATION; RADIOACTIVE WASTE MANAGEMENT; SAFETY; CONTAINMENT; CONTAINERS; INFORMATION RETRIEVAL; 052002; WASTE DISPOSAL AND STORAGE

Citation Formats

Sarrack, A.G., Weber, J.H., and Woody, N.D. Criticality assessment of LLRWDF closure. United States: N. p., 1992. Web. doi:10.2172/10125630.
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Sarrack, A.G., Weber, J.H., & Woody, N.D. Criticality assessment of LLRWDF closure. United States. doi:10.2172/10125630.
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Sarrack, A.G., Weber, J.H., and Woody, N.D. Tue . "Criticality assessment of LLRWDF closure". United States. doi:10.2172/10125630. https://www.osti.gov/servlets/purl/10125630.
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@article{osti_10125630,
title = {Criticality assessment of LLRWDF closure},
author = {Sarrack, A.G. and Weber, J.H. and Woody, N.D.},
abstractNote = {During the operation of the Low Level Radioactive Waste Disposal Facility (LLRWDF), large amounts (greater than 100 kg) of enriched uranium (EU) were buried. This EU came primarily from the closing and decontamination of the Naval Fuels Facility in the time period from 1987--1989. Waste Management Operations (WMO) procedures were used to keep the EU boxes separated to prevent possible criticality during normal operation. Closure of the LLRWDF is currently being planned, and waste stabilization by Dynamic Compaction (DC) is proposed. Dynamic compaction will crush the containers in the LLRWDF and result in changes in their geometry. Research of the LLRWDF operations and record keeping practices have shown that the EU contents of trenches are known, but details of the arrangement of the contents cannot be proven. Reviews of the trench contents, combined with analysis of potential critical configurations, revealed that some portions of the LLRWDF can be expected to be free of criticality concerns while other sections have credible probabilities for the assembly of a critical mass, even in the uncompacted configuration. This will have an impact on the closure options and which trenches can be compacted.},
doi = {10.2172/10125630},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Oct 06 00:00:00 EDT 1992},
month = {Tue Oct 06 00:00:00 EDT 1992}
}
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Technical Report:
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DOI:  10.2172/10125630
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  • ; ;
    During the operation of the Low Level Radioactive Waste Disposal Facility (LLRWDF), large amounts (greater than 100 kg) of enriched uranium (EU) were buried. This EU came primarily from the closing and decontamination of the Naval Fuels Facility in the time period from 1987--1989. Waste Management Operations (WMO) procedures were used to keep the EU boxes separated to prevent possible criticality during normal operation. Closure of the LLRWDF is currently being planned, and waste stabilization by Dynamic Compaction (DC) is proposed. Dynamic compaction will crush the containers in the LLRWDF and result in changes in their geometry. Research of themore » LLRWDF operations and record keeping practices have shown that the EU contents of trenches are known, but details of the arrangement of the contents cannot be proven. Reviews of the trench contents, combined with analysis of potential critical configurations, revealed that some portions of the LLRWDF can be expected to be free of criticality concerns while other sections have credible probabilities for the assembly of a critical mass, even in the uncompacted configuration. This will have an impact on the closure options and which trenches can be compacted.« less

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