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Classification of the MGR Off-Site Utilities System (open access)

Classification of the MGR Off-Site Utilities System

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) offsite utilities system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
High Resolution Upgrade for Core-level Photoemission Spectroscopy (open access)

High Resolution Upgrade for Core-level Photoemission Spectroscopy

Upgraded the high resolution core-level photoemission beamline U4A at the National Synchrotron Light Source (NSLS) so that it has higher resolution ({approx}30-50 meV) over a broader spectral range (10-200 eV) than is currently available at any other photoemission beamline at NSLS. Such an upgraded beamline will prove to be extremely useful in new studies of bimetallic systems and semiconductor interfaces.
Date: August 31, 1999
Creator: Madey, T. E.
Object Type: Report
System: The UNT Digital Library
Classification of the MGR Canistered SNF Disposal Container (open access)

Classification of the MGR Canistered SNF Disposal Container

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) canistered spent nuclear fuel disposal container system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
Hydrologic and Geochemical Controls on the Transport of Radionuclides in Natural Undisturbed Arid Environments as Determined by Accelerator Mass Spectrometry Measurements (open access)

Hydrologic and Geochemical Controls on the Transport of Radionuclides in Natural Undisturbed Arid Environments as Determined by Accelerator Mass Spectrometry Measurements

This project developed low-level analytical methods for the measurement of radionuclides by accelerator mass spectrometry. The contaminant radionuclides potentially measurable by AMS include: 14C, 36Cl, 59Ni, 63Ni, 90Sr, 93Zr, 99Tc, 129I, 239Np, 239Pu, and other actinides. We chose to concentrate on 36Cl, 99Tc, 90Sr, and 129I. These nuclides were globally distributed as fallout during the era of atmospheric nuclear testing, and occur today in almost every environment. They also are prominent contaminant nuclides at a variety of DOE sites. There is a need to develop these low-level methods to observe the migration of radionuclides in natural environments. There are at least three advantages of this: (1) the ability to conduct migration studies in locations most like those of concern to public health, e.g., a ''far-field'' environment; (2) migration research does not have to be conducted at sites of multiple contamination, e.g., by VOC's, which can produce hard-to-interpret results; and (3) it becomes unnecessary to collect research samples that are themselves radioactive waste and are therefore difficult to handle and dispose of in the laboratory. Our approach of examining globally distributed, fallout radionuclides provides another advantage: (4) since the nuclides are globally distributed, migration research can be conducted in any chosen …
Date: December 31, 1999
Creator: Nimz, Gregory J.; Caffee, Marc W. & McAninch, Jeffrey
Object Type: Report
System: The UNT Digital Library
Rapid Mass Spectrometric DNA Diagnostics for Assessing Microbial Community Activity During Bioremediation (open access)

Rapid Mass Spectrometric DNA Diagnostics for Assessing Microbial Community Activity During Bioremediation

Changes in pollutant profiles observed in contaminated soils have been attributed to biological activity when in actuality abiotic processes caused pollutant removal.1 This sometimes casual implication of biodegradation is not acceptable, but understandable, because factors which cause the disappearance of pollutants are not always easy to identify. Several pollutant removal or transformation pathways are possible with most pollutants found in soil and these processes may or may not operate independently. Careful evaluation of bioremediation necessitates that all transformation and removal pathways are anticipated so that the pathways are either controlled or monitored but in practice this is generally not possible. The diminution in pollutant oxidation might track with several candidate loss mechanisms and when this occurs the real cause becomes problematic to pin point. Many factors disguise or prevent the effectual tracking of bioremediation processes among which are three general types of problems: (1) The estimate that only about 0.1% or less of the microorganisms living in soils are culturable leads to the conclusion that the possibility for unknown organisms participating in a biodegradation pathway is high. How should these imperceptible microorganisms be tracked? (2) The diversity of the microcosm is large, yet several different genera have been shown to …
Date: December 31, 1999
Creator: Benner, W. Henry; Hunter-Cevera, Jennie & Jaklevic, Joseph M.
Object Type: Report
System: The UNT Digital Library
CLASSIFICATION OF MGR GROUND CONTROL SYSTEM (open access)

CLASSIFICATION OF MGR GROUND CONTROL SYSTEM

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) ground control system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Garrett, R.J.
Object Type: Report
System: The UNT Digital Library
Extraction and Recovery of Mercury and Lead from Aqueous Waste Streams using Redox-Active Layered Materials (open access)

Extraction and Recovery of Mercury and Lead from Aqueous Waste Streams using Redox-Active Layered Materials

The goals of this program have been to develop a series of new compounds that act as redox recyclable heavy metal ion selective materials. This has been a preliminary exploration into the viability of creating materials that act as selective exchange media. We have historically been involved in the separation of ionic pollutants such as radionuclides or toxic heavy metal ions from water by designing extractants with high selectivities and large capacities. We have also recognized that there is a more urgent need to develop processes that allow the target pollutants to be recovered in a minimal volume of secondary waste and that allow the extractants to be reused or recycled. We have been studying redox active transition-metal-containing extractants that undergo reversible electron transfer activation and deactivation as the target ions are extracted and recovered or that undergo efficient, selective ion exchange.
Date: December 31, 1999
Creator: Dorhout, P. K & Strauss, S. H.
Object Type: Report
System: The UNT Digital Library
Ionizing Radiation Induced Catalysis on Metal Oxide Particles (open access)

Ionizing Radiation Induced Catalysis on Metal Oxide Particles

This project was conducted to determine if ionizing radiation could be used to catalytically destroy organics over semiconducting metal oxide particles. We focused primarily on the destruction of organic chelating agents, such as EDTA, which are known to hamper the separation of radionucleii (such as Sr or Am) from tank waste using current ion exchange methods. Our objective was to determine if ionizing radiation could be used to destroy the chelating capability of species such as EDTA, either by partially or completely decomposing the organic, in order to free radionucleii for efficient separation. Although a considerable amount of information is available in the open literature on the roles of visible/UV light in photocatalysis, little is known about the processes initiated by ionizing radiation. In this sense, the use of ionizing radiation is both novel, and may find an important niche in the pretreatment of mixed waste. An additional aim of the project was determine the mechanism(s) by which the radiocatalysis effect took place and compare it to what is know from visible and UV photocatalytic processes in the literature. The main outcome of this work is a more thorough evaluation of the use of ionizing radiation in the catalytic remediation …
Date: December 31, 1999
Creator: Henderson, Michael A.
Object Type: Report
System: The UNT Digital Library
Classification of the MGR Administration System (open access)

Classification of the MGR Administration System

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) administration system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/9O-55Qy Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
Optimization of Thermochemical, Kinetic, and Electrochemical Factors Governing Partitioning of Radionuclides During Melt Decontamination of Radioactively Contaminated Stainless Steel (open access)

Optimization of Thermochemical, Kinetic, and Electrochemical Factors Governing Partitioning of Radionuclides During Melt Decontamination of Radioactively Contaminated Stainless Steel

Metal waste generated from domestic nuclear operations for defense and commercial applications has led to a growing stockpile of radioactively contaminated scrap metal, much of which is stainless steel. This steel contains large quantities of strategic elements such as nickel and chromium and constitutes a valuable domestic resource [1]. A significant fraction of this material cannot be efficiently surface decontaminated, and burial of this material would be wasteful and expensive, since long term monitoring would be necessary in order to minimize environmental risk. Melt decontamination of this material would maintain the chemical pedigree of the stainless steel, allowing its controlled reuse within the nuclear community. This research addresses the melt decontamination of radioactively contaminated stainless steel by electroslag remelting (ESR). ESR is industrially used for the production of specialty steels and superalloys to remove a variety of contaminates and to improve metal chemistry. Correctly applied, it could maintain the specified chemistry and mechanical properties of the original material while capturing the radioactive transuranic elements in a stable slag phase. The ESR process also produces a high quality metal ingot free of porosity that can be directly forged or rolled into final shapes. The goal of this project was to optimize …
Date: December 31, 1999
Creator: Van den Avyle, James A.; Melgaard, David; Molecke, Martin; Shelmidine, Greg J.; Pal, Uday & Bychkov, Sergie I.
Object Type: Report
System: The UNT Digital Library
Characterization of a new family of metal transporters (open access)

Characterization of a new family of metal transporters

Metal ions are critical nutrients, yet overaccumulation of these same metals can also be toxic. To maintain appropriate intracellular levels, cells require specific metal uptake systems that are subject to precise homeostatic regulation. The long-range goal of our research is to define the molecular mechanism(s) and regulation of metal ion uptake in eukaryotic cells. Integrating genetic, molecular biological and biochemical approaches, we have examined these processes in the yeast Saccharomyces cerevisiae and the plant Arabidopsis thaliana. Both are proven model systems for studying fundamental cellular processes. Our work has focused on the ZIP family of metal transporters which we identified; this family has representatives in bacteria, fungi,plants and animals. IRT1, one of the founding members of the ZIP family, is an essential cation transporter that is expressed in the epidermal cells of iron deficient plant roots and is responsible for uptake of iron from the soil. We now know that t here are 15 ZIP genes in the Arabidopsis genome which can be divided into four different classes, based on their intron/exon arrangements and the similarities among their encoded gene products. The ZIP family members display different substrate specificities for metals and different tissue distributions in Arabidopsis.Moreover, the family members …
Date: December 31, 1999
Creator: Guerinot, Mary L. & Dide, David
Object Type: Report
System: The UNT Digital Library
Development of a High Fluence Neutron Source for Nondestructive Characterization of Nuclear Waste (open access)

Development of a High Fluence Neutron Source for Nondestructive Characterization of Nuclear Waste

We are addressing the need to measure nuclear wastes, residues, and spent fuel in order to process these for final disposition. For example, TRU wastes destined for the WIPP must satisfy extensive characterization criteria outlined in the Waste Acceptance Criteria, the Quality Assurance Program Plan, and the Performance Demonstration Plan. Similar requirements exist for spent fuel and residues. At present, no nondestructive assay (NDA) instrumentation is capable of satisfying all of the PDP test cycles (particularly for Remote-Handled TRU waste). One of the primary methods for waste assay is by active neutron interrogation. The objective of this project is to improve the capability of all active neutron systems by providing a higher intensity neutron source (by about a factor of 1,000) for essentially the same cost, power, and space requirements as existing systems. This high intensity neutron source is an electrostatically confined (IEC) plasma device. The IEC is a symmetric sphere that was originally developed in the 1960s as a possible fusion reactor. It operates as DT neutron generator. Although it is not likely that this device will scale to fusion reactor levels, previous experiments1 have demonstrated a neutron yield of 2 x 1010 neutrons/second on a table-top device that …
Date: December 31, 1999
Creator: Pickrell, Mark M.
Object Type: Report
System: The UNT Digital Library
CLASSIFICATION OF THE MGR UNCANISTERED SNF DISPOSAL CONTAINER (open access)

CLASSIFICATION OF THE MGR UNCANISTERED SNF DISPOSAL CONTAINER

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) uncanistered spent nuclear fuel (SNF) disposal container system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
Enhanced Sludge Processing of HLW: Hydrothermal Oxidation of Chromium, Technetium, and Complexants by Nitrate (open access)

Enhanced Sludge Processing of HLW: Hydrothermal Oxidation of Chromium, Technetium, and Complexants by Nitrate

The objective of this project is to develop the scientific basis for hydrothermal separation of chromium from High Level Waste (HLW) sludges. Our worked is aimed at attaining a fundamental understanding of chromium speciation, oxidation/reduction and dissolution kinetics, reaction mechanisms, and transport properties under hydrothermal conditions in both simple and complex salt solutions that will ultimately lead to an efficient chromium leaching process.
Date: December 31, 1999
Creator: Buelow, Steven J. & Robinson, Jeanne M.
Object Type: Report
System: The UNT Digital Library
A Chaotic-Dynamical Conceptual Model to Describe Fluid flow and Contaminant Transport in a Fractured Vadose zone (open access)

A Chaotic-Dynamical Conceptual Model to Describe Fluid flow and Contaminant Transport in a Fractured Vadose zone

(1) To determine if and when dynamical chaos theory can be used to investigate infiltration of fluid and contaminant transport in heterogeneous soils and fractured rocks. (2) To introduce a new approach to the multiscale characterization of flow and transport in fractured basalt vadose zones and to develop physically based conceptual models on a hierarchy of scales. The following activities are indicative of the success in meeting the project s objectives: A series of ponded infiltration tests, including (1) small-scale infiltration tests (ponded area 0.5 m2) conducted at the Hell s Half Acre site near Shelley, Idaho, and (2) intermediate-scale infiltration tests (ponded area 56 m2) conducted at the Box Canyon site near Arco, Idaho. Laboratory investigations and modeling of flow in a fractured basalt core. A series of small-scale dripping experiments in fracture models. Evaluation of chaotic behavior of flow in laboratory and field experiments using methods from nonlinear dynamics; Evaluation of the impact these dynamics may have on contaminant transport through heterogeneous fractured rocks and soils, and how it can be used to guide remediation efforts; Development of a conceptual model and mathematical and numerical algorithms for flow and transport that incorporate (1) the spatial variability of heterogeneous …
Date: December 31, 1999
Creator: Faybishenko, Boris; Doughty, Christine; Stoops, Thomas M.; Wood, thomas R. & Wheatcraft, Stephen W.
Object Type: Report
System: The UNT Digital Library
CLASSIFICATION OF THE MGR HEALTH SAFETY SYSTEM (open access)

CLASSIFICATION OF THE MGR HEALTH SAFETY SYSTEM

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) health safety system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
CLASSIFICATION OF THE MGR SUBSURFACE EMPLACEMENT TRANSPORTATION SYSTEM (open access)

CLASSIFICATION OF THE MGR SUBSURFACE EMPLACEMENT TRANSPORTATION SYSTEM

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) subsurface emplacement transportation system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Garrett, R.
Object Type: Report
System: The UNT Digital Library
CLASSIFICATION OF THE MGR SURFACE ENVIRONMENTAL MONITORING SYSTEM (open access)

CLASSIFICATION OF THE MGR SURFACE ENVIRONMENTAL MONITORING SYSTEM

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) surface environmental monitoring system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
CLASSIFICATION OF THE MGR SUBSURFACE EXCAVATION SYSTEM (open access)

CLASSIFICATION OF THE MGR SUBSURFACE EXCAVATION SYSTEM

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) subsurface excavation system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Garrett, R.
Object Type: Report
System: The UNT Digital Library
Classification of the MGR Performance Confirmation Data Acquisition/Monitoring System (open access)

Classification of the MGR Performance Confirmation Data Acquisition/Monitoring System

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) performance confirmation data acquisition/monitoring system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMF 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
CLASSIFICATION OF THE MGR WASTE HANDLING BUILDING ELECTRICAL SYSTEM (open access)

CLASSIFICATION OF THE MGR WASTE HANDLING BUILDING ELECTRICAL SYSTEM

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) waste handling building electrical system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Salzman, S. E.
Object Type: Report
System: The UNT Digital Library
Classification of the MGR General Site Transportation System (open access)

Classification of the MGR General Site Transportation System

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) general site transportation system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
Classification of the MGR Site Electrical Power System (open access)

Classification of the MGR Site Electrical Power System

The purpose of this analysis is to document the Quality As.surance (QA) classification of the Monitored Geologic Repository (MGR) site fire protection system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P7 ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998b).
Date: August 31, 1999
Creator: Ziegler, J. A.
Object Type: Report
System: The UNT Digital Library
Interfacial Radiolysis Effects in Tank Waste Speciation (open access)

Interfacial Radiolysis Effects in Tank Waste Speciation

The purpose of this project was to develop an understanding of radiolysis in systems relevant to nuclear wastes stored in tanks at DOE sites such as Hanford, Savannah River, and Idaho. Since these wastes are highly heterogeneous systems, determining the effects of particulate matter on the radiolytic yields was the main focus of interest. When translated to site-specific concerns, quantitative modeling of these processes can be developed once the fundamental phenomena are understood. Interpretation of the results and conclusions to specific issues, especially safety concerns, at the sites was a major goal. The results were transferred to site operators as soon as the experimental observations were confirmed to be reliable.
Date: December 31, 1999
Creator: Orlando, Thom M.; Meisel, Dan & Camaioni, Donald M.
Object Type: Report
System: The UNT Digital Library