192 Matching Results

Results open in a new window/tab.

Life Extension of Aging High-Level Waste Tanks (open access)

Life Extension of Aging High-Level Waste Tanks

The Double Shell Tanks (DSTs) play a critical role in the Hanford High-Level Waste Treatment Complex, and therefore activities are underway to protect and better understand these tanks. The DST Life Extension Program is focused on both tank life extension and on evaluation of tank integrity. Tank life extension activities focus on understanding tank failure modes and have produced key chemistry and operations controls to minimize tank corrosion and extend useful tank life. Tank integrity program activities have developed and applied key technologies to evaluate the condition of the tank structure and predict useful tank life. Program results to date indicate that DST useful life can be extended well beyond the original design life and allow the existing tanks to fill a critical function within the Hanford High-Level Waste Treatment Complex. In addition the tank life may now be more reliably predicted, facilitating improved planning for the use and possible future replacement of these tanks.
Date: February 26, 2002
Creator: Bryson, D.; Callahan, V.; Ostrom, M.; Bryan, W. & Berman, H.
Object Type: Article
System: The UNT Digital Library
Systematic Approach for Decommissioning Planning and Estimating (open access)

Systematic Approach for Decommissioning Planning and Estimating

Nuclear facility decommissioning, satisfactorily completed at the lowest cost, relies on a systematic approach to the planning, estimating, and documenting the work. High quality information is needed to properly perform the planning and estimating. A systematic approach to collecting and maintaining the needed information is recommended using a knowledgebase system for information management. A systematic approach is also recommended to develop the decommissioning plan, cost estimate and schedule. A probabilistic project cost and schedule risk analysis is included as part of the planning process. The entire effort is performed by a experienced team of decommissioning planners, cost estimators, schedulers, and facility knowledgeable owner representatives. The plant data, work plans, cost and schedule are entered into a knowledgebase. This systematic approach has been used successfully for decommissioning planning and cost estimating for a commercial nuclear power plant. Elements of this approach have been used for numerous cost estimates and estimate reviews. The plan and estimate in the knowledgebase should be a living document, updated periodically, to support decommissioning fund provisioning, with the plan ready for use when the need arises.
Date: February 26, 2002
Creator: Dam, A. S.
Object Type: Article
System: The UNT Digital Library
Environmental Remediation Data Management Tools (open access)

Environmental Remediation Data Management Tools

Computer software tools for data management can improve site characterization, planning and execution of remediation projects. This paper discusses the use of two such products that have primarily been used within the nuclear power industry to enhance the capabilities of radiation protection department operations. Advances in digital imaging, web application development and programming technologies have made development of these tools possible. The Interactive Visual Tour System (IVTS) allows the user to easily create and maintain a comprehensive catalog containing digital pictures of the remediation site. Pictures can be cataloged in groups (termed ''tours'') that can be organized either chronologically or spatially. Spatial organization enables the user to ''walk around'' the site and view desired areas or components instantly. Each photo is linked to a map (floor plan, topographical map, elevation drawing, etc.) with graphics displaying the location on the map and any available tour/component links. Chronological organization enables the user to view the physical results of the remediation efforts over time. Local and remote management teams can view these pictures at any time and from any location. The Visual Survey Data System (VSDS) allows users to record survey and sample data directly on photos and/or maps of areas and/or components. …
Date: February 26, 2002
Creator: Wierowski, J. V.; Henry, L. G. & Dooley, D. A.
Object Type: Article
System: The UNT Digital Library
Guidance Tools for Use in Nuclear Material Management Decisions Making (open access)

Guidance Tools for Use in Nuclear Material Management Decisions Making

This paper describes the results of Recommendation 14 of the Integrated Nuclear Materials Management Plan (INMMP) which was the product of a management initiative at the highest levels of the Department of Energy responding to a congressional directive to accelerate the work of achieving integration and cutting long-term costs associated with the management of nuclear materials, with the principal focus on excess materials. The INMMP provided direction to ''Develop policy-level decision support tools to support long-term planning and decision making.'' To accomplish this goal a team from the Savannah River Site, Sandia National Laboratories, Idaho National Engineering and Environmental Laboratory (INEEL), and the U.S. Department of Energy experienced in the decision-making process developed a Guidebook to Decision-Making Methods. The goal of the team organized to implement Recommendation 14 was to instill transparency, consistency, rigor, and discipline in the DOE decision process. The guidebook introduces a process and a selection of proven methods for disciplined decision-making so that the results are clearer, more transparent, and easier for reviewers to understand and accept. It was written to set a standard for a consistent decision process.
Date: February 26, 2002
Creator: Johnson, G. V.; Baker, D. J.; Sorenson, K. B. & Boeke, S. G.
Object Type: Article
System: The UNT Digital Library
High-Level Waste Melter Review (open access)

High-Level Waste Melter Review

The U.S. Department of Energy (DOE) is faced with a massive cleanup task in resolving the legacy of environmental problems from years of manufacturing nuclear weapons. One of the major activities within this task is the treatment and disposal of the extremely large amount of high-level radioactive (HLW) waste stored at the Hanford Site in Richland, Washington. The current planning for the method of choice for accomplishing this task is to vitrify (glassify) this waste for disposal in a geologic repository. This paper describes the results of the DOE-chartered independent review of alternatives for solidification of Hanford HLW that could achieve major cost reductions with reasonable long-term risks, including recommendations on a path forward for advanced melter and waste form material research and development. The potential for improved cost performance was considered to depend largely on increased waste loading (fewer high-level waste canisters for disposal), higher throughput, or decreased vitrification facility size.
Date: February 26, 2002
Creator: Ahearne, J.; Gentilucci, J.; Pye, L. D.; Weber, T.; Woolley, F.; Machara, N. P. et al.
Object Type: Article
System: The UNT Digital Library
Nuclear Materials Stewardship Within the DOE Environmental Management Program (open access)

Nuclear Materials Stewardship Within the DOE Environmental Management Program

The Department of Energy (DOE) Environmental Management (EM) Program has made significant progress in planning disposition of its excess nuclear materials and has recently completed several noteworthy studies. Since establishment in 1997, the EM Nuclear Material Stewardship Program has developed disposition plans for excess nuclear materials to support facility deactivation. All nuclear materials have been removed from the Miamisburg Environmental Management Project (Mound), and disposition planning is nearing completion for the Fernald Environmental Management Project and the Rocky Flats Environmental Technology Site. Only a few issues remain for materials at the Hanford and Idaho sites. Recent trade studies include the Savannah River Site Canyons Nuclear Materials Identification Study, a Cesium/Strontium Management Alternatives Trade Study, a Liquid Technical Standards Trade Study, an Irradiated Beryllium Reflectors with Tritium study, a Special Performance Assessment Required Trade Study, a Neutron Source Trade Study, and development of discard criteria for uranium. A Small Sites Workshop was also held. Potential and planned future activities include updating the Plutonium-239 storage study, developing additional packaging standards, developing a Nuclear Material Disposition Handbook, determining how to recover or dispose of Pu-244 and U-233, and working with additional sites to define disposition plans for their nuclear materials.
Date: February 26, 2002
Creator: Bilyeu, J. D.; Kiess, T. E. & Gates, M. L.
Object Type: Article
System: The UNT Digital Library
The Waste Isolation Pilot Plant: A Success Story with International Cooperation (open access)

The Waste Isolation Pilot Plant: A Success Story with International Cooperation

The U.S. Department of Energy (DOE) Carlsbad Field Office (CBFO) administers and operates the Waste Isolation Pilot Plant (WIPP) site, which hosts a deep geologic repository for safe disposal of U.S. defense-related TRU waste and is located 42 kilometers (km) east of Carlsbad, New Mexico. CBFO also manages the National Transuranic Waste Program (NTP), which oversees TRU waste management from generation to disposal. The WIPP began receiving waste in March 1999. In some areas of broad international interest, the CBFO has developed a leading expertise through its 25-year WIPP repository and TRU waste characterization activities. In addition to participating in relevant and beneficial experiments, the CBFO will provide the international community convenient access to this information by sponsoring and hosting symposia and workshops on relevant topics and by participation in international waste management organizations and topical meetings. In recognition of the successes at WIPP, the Inter national Atomic Energy Agency (IAEA) has designated WIPP as an International Center of Excellence and part of IAEA's Network of Centers of Excellence. The IAEA will foster cooperative training in and demonstration of waste disposal technologies in underground research facilities (URFs).such as WIPP. The CBFO, supported by its Science Advisor, has agreed to exchange …
Date: February 26, 2002
Creator: Matthews, M.
Object Type: Article
System: The UNT Digital Library
Remote Sensing Analysis of the Sierra Blanca (Faskin Ranch) Low-Level Radioactive Waste Disposal Site, Hudspeth County, Texas (open access)

Remote Sensing Analysis of the Sierra Blanca (Faskin Ranch) Low-Level Radioactive Waste Disposal Site, Hudspeth County, Texas

Remote sensing images provide useful physical information, revealing such features as geological structure, vegetation, drainage patterns, and variations in consolidated and unconsolidated lithologies. That technology has been applied to the failed Sierra Blanca (Faskin Ranch) shallow burial low-level radioactive waste disposal site selected by the Texas Low-Level Radioactive Waste Disposal Authority. It has been re-examined using data from LANDSAT satellite series. The comparison of the earlier LANDSAT V (5/20/86) (30-m resolution) with the later new, higher resolution ETM imagery (10/23/99) LANDSAT VII data (15-m resolution) clearly shows the superiority of the LANDSAT VII data. The search for surficial indications of evidence of fatal flaws at the Sierra Blanca site utilizing was not successful, as it had been in the case of the earlier remote sensing analysis of the failed Fort Hancock site utilizing LANDSAT V data. The authors conclude that the tectonic activity at the Sierra Blanca site is much less recent and active than in the previously studied Fort Hancock site. The Sierra Blanca site failed primarily on the further needed documentation concerning a subsurface fault underneath the site and environmental justice issues. The presence of this fault was not revealed using the newer LANDSAT VII data. Despite this …
Date: February 26, 2002
Creator: LeMone, D. V.; Dodge, R.; Xie, H.; Langford, R. P. & Keller, G. R.
Object Type: Article
System: The UNT Digital Library
Application of Archimedes Filter for Reduction of Hanford HLW (open access)

Application of Archimedes Filter for Reduction of Hanford HLW

Archimedes Technology Group, Inc., is developing a plasma mass separator called the Archimedes Filter that separates waste oxide mixtures ion by ion into two mass groups: light and heavy. For the first time, it is feasible to separate large amounts of material atom by atom in a single pass device. Although vacuum ion based electromagnetic separations have been around for many decades, they have traditionally depended on ion beam manipulation. Neutral plasma devices, on the other hand, are much easier, less costly, and permit several orders of magnitude greater throughput. The Filter has many potential applications in areas where separation of species is otherwise difficult or expensive. In particular, radioactive waste sludges at Hanford have been a particularly difficult issue for pretreatment and immobilization. Over 75% of Hanford HLW oxide mass (excluding water, carbon, and nitrogen) has mass less than 59 g/mol. On the other hand, 99.9% of radionuclide activity has mass greater than 89 g/mol. Therefore, Filter mass separation tuned to this cutoff would have a dramatic effect on the amount of IHLW produced--in fact IHLW would be reduced by a factor of at least four. The Archimedes Filter is a brand new tool for the separations specialist's toolbox. …
Date: February 26, 2002
Creator: Gilleland, J.; Agnew, S.; Cluggish, B.; Freeman, R.; Miller, R.; Putvinski, S. et al.
Object Type: Article
System: The UNT Digital Library
Processing of Oak Ridge Mixed Waste Labpacks (open access)

Processing of Oak Ridge Mixed Waste Labpacks

The Oak Ridge Site Treatment Plan (STP) issued under a Tennessee Commissioner's Order includes a compliance milestone related to treatment of mixed waste labpacks on the Oak Ridge sites. The treatment plan was written and approved in Fiscal Year 1997. The plan involved approximately 1,100 labpacks and 7,400 on-the-shelf labpackable items stored at three Department of Energy (DOE) sites on the Oak Ridge Reservation (ORR). The labpacks and labpack items consist of liquids and solids with various chemical constituents and radiological concerns. The waste must be processed for shipment to a commercial hazardous waste treatment facility or treatment utilizing a Broad Spectrum mixed waste treatment contract. This paper will describe the labpack treatment plan that was developed as required by the Site Treatment Plan and the operations implemented to process the labpack waste. The paper will discuss the labpack inventory in the treatment plan, treatment and disposal options, processing strategies, project risk assessment, and current project status.
Date: February 26, 2002
Creator: Estes, C. H.; Franco, P. & Bisaria, A.
Object Type: Article
System: The UNT Digital Library
An Exact Solution for the Assessment of Nonequilibrium Sorption of Radionuclides in the Vadose Zone (open access)

An Exact Solution for the Assessment of Nonequilibrium Sorption of Radionuclides in the Vadose Zone

In a report on model evaluation, the authors ran the HYDRUS Code, among other transport codes, to evaluate the impacts of nonequilibrium sorption sites on the time-evolution of 99Tc and 90Sr through the vadose zone. Since our evaluation was based on a rather low, annual recharge rate, many of the numerical results derived from HYDRUS indicated that the nonequilibrium sorption sites, in essence, acted as equilibrium sorption sites. To help explain these results, we considered a ''stripped-down'' version of the HYDRUS system. This ''stripped-down'' version possesses two dependent variables, one for the radionuclides in solution and the other for the radionuclides adsorbed to the nonequilibrium sites; and it possesses constant physical parameters. The resultant governing equation for the radionuclides in solution is a linear, advection-dispersion-reaction (i.e., radioactive decay) partial differential equation containing a history integral term accounting for the nonequilibrium sorption sites. It is this ''stripped-down'' version, which is the subject of this paper. We found an exact solution to this new version of the model. The exact solution is given in terms of a single definite integral of terms involving elementary functions of the independent variables and the system parameters. This integral possesses adequate convergence properties and is easy …
Date: February 26, 2002
Creator: Drake, R. L. & Chen, J-S.
Object Type: Article
System: The UNT Digital Library
Development of a Selective Calixarene Sensor for Uranium (open access)

Development of a Selective Calixarene Sensor for Uranium

Traditionally, measurements of uranium in wastewater have been obtained by laboratory based instrumentation, such as inductively coupled plasma spectroscopy, ion-chromatography and radiochemical methods. However, such methods and equipment, whilst offering excellent sensitivity and reproducibility, are far too large and heavy to be portable. Therefore, there has been a lot of interest in developing a portable sensor to carry out uranium measurements. This work describes how a class of molecule called calixarenes have been used to develop a sensing methodology for measuring uranium concentration at low levels. This has been achieved by taking the established coordinating properties of the calixarene molecule for uranium and then adding functionalities to the molecule to make it adhere to metal surfaces. This way, a layer of the uranophilic molecule has been prepared on electrode surfaces, one molecule thick. These electrodes have been shown to be sensitive to uranium between 5 and 300 parts per billion. Using these modified electrodes, a portable device has been developed, which potentially allows for measurement of uranium in the field. This sensor therefore presents a very significant advantage in that it allows for rapid determination of low levels of uranium in wastewater, whilst offering portability.
Date: February 26, 2002
Creator: Evans-Thompson, C.; Field, S. E.; Jones, A. H.; Kan, M. J.; Hall, C. W. & Nicholson, G. P.
Object Type: Article
System: The UNT Digital Library
Planning for the Management and Disposition of Newly Generated TRU Waste from REDC (open access)

Planning for the Management and Disposition of Newly Generated TRU Waste from REDC

This paper describes the waste characteristics of newly generated transuranic waste from the Radiochemical Engineering and Development Center at the Oak Ridge National Laboratory and the basic certification structure that will be proposed by the University of Tennessee-Battelle and Bechtel Jacobs Company LLC to the Waste Isolation Pilot Plant for this waste stream. The characterization approach uses information derived from the active production operations as acceptable knowledge for the Radiochemical Engineering and Development Center transuranic waste. The characterization approach includes smear data taken from processing and waste staging hot cells, as well as analytical data on product and liquid waste streams going to liquid waste disposal. Bechtel Jacobs Company and University of Tennessee-Battelle are currently developing the elements of a Waste Isolation Pilot Plant-compliant program with a plan to be certified by the Waste Isolation Pilot Plant for shipment of newly generated transuranic waste in the next few years. The current activities include developing interface plans, program documents, and waste stream specific procedures.
Date: February 26, 2002
Creator: Coffey, D. E.; Forrester, T. W. & Krause, T.
Object Type: Article
System: The UNT Digital Library
Evaluation of the Parameters of Radioactive Contamination of Soils (open access)

Evaluation of the Parameters of Radioactive Contamination of Soils

After Chornobyl NPP (ChNPP) accident the territory near destroyed Unit 4 (that now with the special confinement has the name the ''Shelter'' object) is contaminated of fuel fallouts. During liquidation of the accident consequences this territory was covered with pure earth, concrete, etc. As a result a contaminated anthropogenic layer of the soil on the depth up to 10 m was formed. Now the problem of contamination estimation and the soils management arose. For this tasks a gamma logging method was modified conformably to ChNPP conditions. The methods for necessary coefficients receiving and log treatment have been suggested.
Date: February 26, 2002
Creator: M.I., Panasyuk; A.D., Skorbun & O.O., Klyuchnikov
Object Type: Article
System: The UNT Digital Library
The Nuclear Material Focus Area Roadmapping Process Utilizing Environmental Management Complex-Wide Nuclear Material Disposition Pathways (open access)

The Nuclear Material Focus Area Roadmapping Process Utilizing Environmental Management Complex-Wide Nuclear Material Disposition Pathways

This paper describes the process that the Nuclear Materials Focus Area (NMFA) has developed and utilizes in working with individual Department of Energy (DOE) sites to identify, address, and prioritize research and development efforts in the stabilization, disposition, and storage of nuclear materials. By associating site technology needs with nuclear disposition pathways and integrating those with site schedules, the NMFA is developing a complex wide roadmap for nuclear material technology development. This approach will leverage technology needs and opportunities at multiple sites and assist the NMFA in building a defensible research and development program to address the nuclear material technology needs across the complex.
Date: February 26, 2002
Creator: Sala, D. R.; Furhman, P. & Smith, J. D.
Object Type: Article
System: The UNT Digital Library
Driving Forces and Priorities in the Hungarian Radioactive Waste Management (open access)

Driving Forces and Priorities in the Hungarian Radioactive Waste Management

Hungary, being a candidate state to the European Union, pays particular attention to the measures that are typically considered as good practice within the EU when developing and implementing its national program for the safe management of spent fuel and radioactive waste. The Public Agency for Radioactive Waste Management (PURAM) has been designated to carry out the multilevel tasks in the field of radioactive waste management. In accordance with changes in infrastructure, Hungary is about to make significant strategic and technical decisions. There are several technical priorities for the coming years, such as improving the existing L/ILW repository, construction of a new repository for L/ILW, extension of the interim storage facility for spent fuel and setting up a revised back-end policy. Preparations for decommissioning of the nuclear facilities have to be developed as well. The paper outlines the main problem areas as well as the approach to managing radioactive wastes. It will be concluded that priorities can be set, but key dates and deadlines will always contain an element of uncertainty due to public and political acceptance problems.
Date: February 26, 2002
Creator: Takats, F. & Ormai, P.
Object Type: Article
System: The UNT Digital Library
Two Approaches to the Geologic Disposal of Long-Lived Nuclear Waste: Yucca Mountain, Nevada and the Waste Isolation Pilot Plant, Carlsbad, New Mexico (open access)

Two Approaches to the Geologic Disposal of Long-Lived Nuclear Waste: Yucca Mountain, Nevada and the Waste Isolation Pilot Plant, Carlsbad, New Mexico

A key component of the US energy program is to provide for the safe and permanent isolation of spent nuclear fuel and long-lived radioactive waste produced through programs related to national defense and the generation of electric power by nuclear utilities. To meet this challenge, the US Department of Energy (DOE) has developed a multi-faceted approach to the geologic disposal of long-lived nuclear wastes. Two sites are being developed or studied as current or potential deep geologic repositories for long lived radioactive wastes, the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico and Yucca Mountain, Nevada.
Date: February 26, 2002
Creator: Levich, R. A.; Patterson, R. L. & Linden, R. M.
Object Type: Article
System: The UNT Digital Library
Development and Use of the Dual-Mode Plasma Torch (open access)

Development and Use of the Dual-Mode Plasma Torch

After several years of development, a commercially available high-temperature treatment system has been developed and installed that treats heterogeneous low-level radioactive waste. High temperature plasma processing, unique torch design and operating features make it feasible to achieve a volume reduced, permanent, high integrity waste form while eliminating the personnel exposure and costs associated with conventional sorting, characterizing and handling. Plasma technology can also be used to treat previous conditioned waste packages that no longer meet the current acceptance criteria for final disposal. Plasma treatment can result, in many cases, in a substantial volume reduction, which lowers the final disposal costs. This paper covers the recently patented dual mode plasma torch design(1), the lessons learned that fostered its development and the advantages it brings to radioactive waste processing. This paper also provides current full scale Plasma Arc Centrifugal Treatment (PACT) project status and how the dual mode torch is being used in the PACT system.
Date: February 26, 2002
Creator: Womack, Ronald & Shuey, Mark
Object Type: Article
System: The UNT Digital Library
Licensing Support Network: An Electronic Discovery System (open access)

Licensing Support Network: An Electronic Discovery System

The necessary authorization for the U. S. Department of Energy's (DOE) Office of Civilian Radioactive Waste Management (OCRWM) to submit a License Application (LA) is contingent upon the policy process defined in the Nuclear Waste Policy Act, as amended (NWPA), with some steps yet to occur. In spite of this uncertainty, the DOE must take prudent and appropriate action now, and over the next several years, to prepare for submittal of an application and to facilitate the U. S. Nuclear Regulatory Commission (NRC) review of this application, if the Yucca Mountain site is recommended and approved for repository development. One of these steps the DOE has taken involves working with the NRC's Advisory Review Panel to develop Licensing Support Network (LSN) requirements and guidelines. The NRC has made a prototype of the LSN web page available at www.LSNNET.gov. The OCRWM part of the LSN currently has an indefinite life cycle and may need to remain in existence until the repository is closed, which could be as long as 325 years.
Date: February 26, 2002
Creator: Gil, A. V.; Jensen, D. & McKinnon, B.
Object Type: Article
System: The UNT Digital Library
Anomalies in Proposed Regulations for the Release of Redundant Material from Nuclear and Non-nuclear Industries (open access)

Anomalies in Proposed Regulations for the Release of Redundant Material from Nuclear and Non-nuclear Industries

Now that increasing numbers of nuclear power stations are reaching the end of their commercially useful lives, the management of the large quantities of very low level radioactive material that arises during their decommissioning has become a major subject of discussion, with very significant economic implications. Much of this material can, in an environmentally advantageous manner, be recycled for reuse without radiological restrictions. Much larger quantities--2-3 orders of magnitude larger--of material, radiologically similar to the candidate material for recycling from the nuclear industry, arise in non-nuclear industries like coal, fertilizer, oil and gas, mining, etc. In such industries, naturally occurring radioactivity is artificially concentrated in products, by-products or waste to form TENORM (Technologically Enhanced Naturally Occurring Radioactive Material). It is only in the last decade that the international community has become aware of the prevalence of T ENORM, specially the activity levels and quantities arising in so many nonnuclear industries. The first reaction of international organizations seems to have been to propose ''double'' standards for the nuclear and non-nuclear industries, with very stringent release criteria for radioactive material from the regulated nuclear industry and up to a hundred times more liberal criteria for the release/exemption of TENORM from the as …
Date: February 26, 2002
Creator: Menon, S.
Object Type: Article
System: The UNT Digital Library
Protection of Operators and Environment - the Safety Concept of the Karlsruhe Vitrification Plant VEK (open access)

Protection of Operators and Environment - the Safety Concept of the Karlsruhe Vitrification Plant VEK

The Karlsruhe Vitrification Plant (VEK) plant is a milestone in decommissioning and complete dismantling of the former Karlsruhe Reprocessing Plant WAK, which is in an advanced stage of disassembly. The VEK is scheduled to vitrify approx. 70 m3 of the highly radioactive liquid waste (HLW) resulting from reprocessing. Site preparation, civil work and component manufacturing began in 1999. The building will be finalized by mid of 2002, hot vitrification operation is currently scheduled for 2004/2005. Provisions against damages arising from construction and operation of the VEK had to be made in accordance with the state of the art as laid down in the German Atomic Law and the Radiation Protection Regulations. For this purpose, the appropriate analysis of accidents and their external and internal impacts were investigated. During the detailed design phase, a failure effects analysis was carried out, in which single events were studied with respect to the objectives of protection and ensuring activity containment, limiting radioactive discharges to the environment and protecting of the staff. Parallel to the planning phase of the VEK plant a cold prototype test facility (PVA) covering the main process steps was constructed and operated at the Institut fuer Nukleare Entsorgung (INE) of FZK. …
Date: February 26, 2002
Creator: Fleisch, J.; Kuttruf, H.; Lumpp, W.; Pfeifer, W.; Roth, G. & Weisenburger, S.
Object Type: Article
System: The UNT Digital Library
ALARA Controls and the Radiological Lessons Learned During the Uranium Fuel Removal Projects at the Molten Salt Reactor Experiment (open access)

ALARA Controls and the Radiological Lessons Learned During the Uranium Fuel Removal Projects at the Molten Salt Reactor Experiment

The removal of uranium-233 (233 U) from the auxiliary charcoal bed (ACB) of the Molten Salt Reactor Experiment (MSRE), performed from January through May 2001, created both unique radiological challenges and widely-applicable lessons learned. In addition to the criticality concerns and alpha contamination, 233U has an associated intense gamma photon from the cocontaminant uranium-232 (232U) decaying to thallium-208 (208Tl). Therefore, rigorous contamination controls and significant shielding were implemented. Extensive, timed mock-up training was also imperative to minimize individual and collective personnel exposures. Back-up shielding and containment techniques (that had been previously developed for defense in depth) were used successfully to control significant, changed conditions. Additional controls were placed on tests and on recovery designs to assure a higher level of safety throughout the removal operations. This paper delineates the manner in which each difficulty was solved, while relating the relevance of the results and the methodology to other projects with high dose-rate, highly-contaminated ionizing radiation hazards. Because of the distinctive features of and current interest in molten salt technology, a brief overview is provided. Also presented is the detailed, practical application of radiological controls integrated into, rather than added after, each evolution of the project--thus demonstrating the broad-based benefits of …
Date: February 26, 2002
Creator: Gilliam, B. J.; Chapman, J. A. & Jugan, M. R.
Object Type: Article
System: The UNT Digital Library
Barriers and Issues Related to Achieving Final Disposition of Depleted Uranium (open access)

Barriers and Issues Related to Achieving Final Disposition of Depleted Uranium

Approximately 750,000 metric tons (MT) of surplus depleted uranium (DU) in various chemical forms are stored at several Department of Energy (DOE) sites throughout the United States. Most of the DU is in the form of DU hexafluoride (DUF6) that resulted from uranium enrichment operations over the last several decades. DOE plans to convert the DUF6 to ''a more stable form'' that could be any one or combination of DU tetrafluoride (DUF4 or green salt), DU oxide (DUO3, DUO2, or DU3O8), or metal depending on the final disposition chosen for any given quantity. Barriers to final disposition of this material have existed historically and some continue today. Currently, the barriers are more related to finding uses for this material versus disposing as waste. Even though actions are beginning to convert the DUF6, ''final'' disposition of the converted material has yet to be decided. Unless beneficial uses can be implemented, DOE plans to dispose of this material as waste. This expresses the main barrier to DU disposition; DOE's strategy is to dispose unless uses can be found while the strategy should be only dispose as a last resort and make every effort to find uses. To date, only minimal research programs …
Date: February 26, 2002
Creator: Gillas, D. L. & Chambers, B. K.
Object Type: Article
System: The UNT Digital Library
Trace Chlorinated Organics Analysis in Highly Radioactive Samples-Problems and Solutions (open access)

Trace Chlorinated Organics Analysis in Highly Radioactive Samples-Problems and Solutions

This paper discusses some of the problems that are associated with the analysis of highly radioactive samples for chlorinated organic compounds at the part per trillion level. To date, both high fission product activity and transuranic activity have been handle successfully. Communication issues, sample handling, transfer between laboratories and analytical challenges are discussed.
Date: February 26, 2002
Creator: Macek, P.; Hawthorne, L.; Hass, J. R. & Harvan, D.
Object Type: Article
System: The UNT Digital Library