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Estimate of the Sources of Plutonium-Containing Wastes Generated from MOX Fuel Production in Russia
In Russia, mixed oxide (MOX) fuel is produced in a pilot facility ''Paket'' at ''MAYAK'' Production Association. The Mining-Chemical Combine (MCC) has developed plans to design and build a dedicated industrial-scale plant to produce MOX fuel and fuel assemblies (FA) for VVER-1000 water reactors and the BN-600 fast-breeder reactor, which is pending an official Russian Federation (RF) site-selection decision. The design output of the plant is based on a production capacity of 2.75 tons of weapons plutonium per year to produce the resulting fuel assemblies: 1.25 tons for the BN-600 reactor FAs and the remaining 1.5 tons for VVER-1000 FAs. It is likely the quantity of BN-600 FAs will be reduced in actual practice. The process of nuclear disarmament frees a significant amount of weapons plutonium for other uses, which, if unutilized, represents a constant general threat. In France, Great Britain, Belgium, Russia, and Japan, reactor-grade plutonium is used in MOX-fuel production. Making MOX-fuel for CANDU (Canada) and pressurized water reactors (PWR) (Europe) is under consideration in Russia. If this latter production is added, as many as 5 tons of Pu per year might be processed into new FAs in Russia. Many years of work and experience are represented in …
Date:
February 26, 2002
Creator:
Kudinov, K. G.; Tretyakov, A. A.; Sorokin, Yu. P.; Bondin, V. V.; Manakova, L. F. & Jardine, L. J.
Object Type:
Article
System:
The UNT Digital Library
The Remote-Handled TRU Waste Program
RH TRU Waste is radioactive waste that requires shielding in addition to that provided by the container to protect people nearby from radiation exposure. By definition, the radiation dose rate at the outer surface of the container is greater than 200 millirem per hour and less than 1,000 rem per hour. The DOE is proposing a process for the characterization of RH TRU waste planned for disposal in the WIPP. This characterization process represents a performance-driven approach that satisfies the requirements of the New Mexico Hazardous Waste Act, the Environmental Protection Agency (EPA) regulations for WIPP long-term performance, the transportation requirements of the Nuclear Regulatory Commission (NRC) and the Department of Transportation, as well as the technical safety requirements of RH TRU waste handling. The transportation, management and disposal of RH TRU waste is regulated by external government agencies as well as by the DOE itself. Externally, the characterization of RH-TRU waste for disposal at the WIPP is regulated by 20.4.1.500 New Mexico Administrative Code (incorporating 40 CFR 261.13) for the hazardous constituents and 40 CFR 194.24 for the radioactive constituents. The Nuclear Regulatory Commission certifies the shipping casks and the transportation system must meet DOT regulations. Internally, the DOE …
Date:
February 26, 2002
Creator:
Gist, C. S.; Plum, H. L.; Wu, C. F.; Most, W. A.; Burrington, T. P. & Spangler, L. R.
Object Type:
Article
System:
The UNT Digital Library
RFNC-VNIIEF Capabilities to Production High Pure Isotopes for Scientific and Medical Applications
In the technical paper there is presented the information on the basic equipment and more than thirty-year experience of RFNC-VNIIEF activities in the sphere of producing highly enriched isotopes of actinide elements--thorium, uranium, neptunium, plutonium, americium and curium--for scientific researches and practical applications. Electromagnetic separator and radiochemical methods provide obtaining of superpure isotope samples for nuclear-physical radiometric and mass-spectrometric equipment, and also as tracers when analyzing environmental contamination. There are presented the structure of the laboratory occupied with these isotopes electromagnetic separation as well as the nomenclature and characteristics of the specimens supplied. There are stated science and engineering elaborations of technologies aimed at producing alpha-ray radiating radionuclides--thorium-229, thorium-228, actinium-225, radium-224--for the purpose of anti-cancer therapy using bismuth-212 and bismuth-213 produced by the specially developed generators. There are presented the basic directions of cooperation with other Russian Institutes in developing this promising line of conversion.
Date:
February 26, 2002
Creator:
Vesnovskii, S. P.
Object Type:
Article
System:
The UNT Digital Library
RH-TRU Waste Inventory Characterization by AK and Proposed WIPP RH-TRU Waste Characterization Objectives
The U.S. Department of Energy (DOE)-Carlsbad Field Office (CBFO) has developed draft documentation to present the proposed Waste Isolation Pilot Plant (WIPP) remote-handled (RH-) transuranic (TRU) waste characterization program to its regulators, the U.S. Environmental Protection Agency and the New Mexico Environment Department. Compliance with Title 40, Code of Federal Regulations, Parts 191 and 194; the WIPP Land Withdrawal Act (PL 102-579); and the WIPP Hazardous Waste Facility Permit, as well as the Certificates of Compliance for the 72-B and 10-160B Casks, requires that specific waste parameter limits be imposed on DOE sites disposing of TRU waste at WIPP. The DOE-CBFO must control the sites' compliance with the limits by specifying allowable characterization methods. As with the established WIPP contact handled TRU waste characterization program, the DOE-CBFO has proposed a Remote-Handled TRU Waste Acceptance Criteria (RH-WAC) document consolidating the requirements from various regulatory drivers and proposed allowable characterization methods. These criteria are consistent with the recommendation of a recent National Academy Sciences/National Research Council to develop an RH-TRU waste characterization approach that removes current self imposed requirements that lack a legal or safety basis. As proposed in the draft RH-WAC and other preliminary documents, the DOE-CBFO RH-TRU waste characterization program …
Date:
February 26, 2002
Creator:
Most, W. A.; Kehrman, R.; Gist, C.; Biedscheid, J.; Devarakonda, J. & Whitworth, J.
Object Type:
Article
System:
The UNT Digital Library
Post Closure Safety of the Morsleben Repository
After the completion of detailed studies of the suitability the twin-mine Bartensleben-Marie, situated in the Federal State of Saxony-Anhalt (Germany), was chosen in 1970 for the disposal of low and medium level radioactive waste. The waste emplacement started in 1978 in rock cavities at the mine's fourth level, some 500 m below the surface. Until the end of the operational phase in 1998 in total about 36,800 m{sup 3} of radioactive waste was disposed of. The Morsleben LLW/ILW repository (ERAM) is now under licensing for closure. After completing the licensing procedure the repository will be sealed and backfilled to exclude any undue future impact onto man or the environment. The main safety objective is to protect the biosphere from the harmful effects of the disposed radionuclides. Furthermore, classical or conventional requirements call for ruling out or minimizing other unfavorable environmental effects. The ERAM is an abandoned rock salt and potash mine. As a consequence it has a big void volume, however small parts of the cavities are backfilled with crushed salt rocks. Other goals of the closure concept are therefore a long-term stabilization of the cavities to prevent a dipping or buckling of the ground surface. In addition, groundwater protection …
Date:
February 26, 2002
Creator:
Preuss, J.; Eilers, G.; Mauke, R.; Moeller-Hoeppe, N.; Engelhardt, H.-J.; Kreienmeyer, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Radioactive Releases Impact from Kozloduy Nuclear Power Plant, Bulgaria into the Environment
The aim of this paper is to present a general overview of the radioactive releases impact generated by Kozloduy Nuclear Power Plant (KNPP), Bulgaria to the environment and public. The liquid releases presented are known as the so called controlled water discharges, that are generated after reprocessing of the inevitable accumulated liquid radioactive waste in the plant operation process. The radionuclides containing in the liquid releases are given in the paper as a result of systematic measuring. Database for radiation doses evaluation on the public around Kozloduy NPP site is developed using IAEA LADTAP computerized program. The computer code LADTAP represents realization of a model that evaluates the public dose as a result of NPP releases under normal operation conditions. The results of this evaluation were the basic licensing document for a new liquid release limit.
Date:
February 26, 2002
Creator:
Genchev, G. T.; Kuleff, I.; Tanev, N. T.; Delistoyanova, E. S. & Guentchev, T.
Object Type:
Article
System:
The UNT Digital Library
Long-Term Waste Package Degradation Studies at the Yucca Mountain Potential High-Level Nuclear Waste Repository
The Site Recommendation (SR) process for the potential repository for spent nuclear fuel (SNF) and high-level nuclear waste (HLW) at Yucca Mountain, Nevada is underway. Fulfillment of the requirements for substantially complete containment of the radioactive waste emplaced in the potential repository and subsequent slow release of radionuclides from the Engineered Barrier System (EBS) into the geosphere will rely on a robust waste container design, among other EBS components. Part of the SR process involves sensitivity studies aimed at elucidating which model parameters contribute most to the drip shield and waste package degradation characteristics. The model parameters identified included (a) general corrosion rate model parameters (temperature-dependence and uncertainty treatment), and (b) stress corrosion cracking (SCC) model parameters (uncertainty treatment of stress and stress intensity factor profiles in the Alloy 22 waste package outer barrier closure weld regions, the SCC initiation stress threshold, and the fraction of manufacturing flaws oriented favorably for through-wall penetration by SCC). These model parameters were reevaluated and new distributions were generated. Also, early waste package failures due to improper heat treatment were added to the waste package degradation model. The results of these investigations indicate that the waste package failure profiles are governed by the manufacturing …
Date:
February 26, 2002
Creator:
Mon, K. G.; Bullard, B. E.; Longsine, D. E.; Mehta, S.; Lee, J. H. & Monib, A. M.
Object Type:
Article
System:
The UNT Digital Library
Oak Ridge National Laboratory Gunite and Associated Tanks Stabilization Project-Low-Tech Approach with High-Tech Results
Environmental restoration of the Gunite and Associated Tanks (GAAT) at the Oak Ridge National Laboratory (ORNL) was a priority to the U. S. Department of Energy (DOE) because of their age and deteriorating structure. These eight tanks ranging up to 170,000 gallons in capacity were constructed in 1943 of a Gunite or ''sprayed concrete material'' as part of the Manhattan Project. The tanks initially received highly radioactive waste from the Graphite Reactor and associated chemical processing facilities. The waste was temporarily stored in these tanks to allow for radioactive decay prior to dilution and release into surface waters. Over time, additional wastes from ongoing ORNL operations (e.g., isotope separation and materials research) were discharged to the tanks for storage and treatment. These tanks were taken out of service in the 1970s. Based on the structure integrity of GAAT evaluated in 1995, the worst-case scenario for the tanks, even assuming they are in good condition, is to remain empty. A recently completed interim action conducted from April 1997 through September 2000 removed the tank liquids and residual solids to the extent practical. Interior video surveys of the tanks indicated signs of degradation of the Gunite material. The tanks continued to receive …
Date:
February 26, 2002
Creator:
Brill, A.; Alsup, T. & Bolling, D.
Object Type:
Article
System:
The UNT Digital Library
Low Level Waste Conceptual Design Adaption to Poor Geological Conditions
Since the early eighties, several studies have been carried out in Belgium with respect to a repository for the final disposal of low-level radioactive waste (LLW). In 1998, the Belgian Government decided to restrict future investigations to the four existing nuclear sites in Belgium or sites that might show interest. So far, only two existing nuclear sites have been thoroughly investigated from a geological and hydrogeological point of view. These sites are located in the North-East (Mol-Dessel) and in the mid part (Fleurus-Farciennes) of the country. Both sites have the disadvantage of presenting poor geological and hydrogeological conditions, which are rather unfavorable to accommodate a surface disposal facility for LLW. The underground of the Mol-Dessel site consists of neogene sand layers of about 180 m thick which cover a 100 meters thick clay layer. These neogene sands contain, at 20 m depth, a thin clayey layer. The groundwater level is quite close to the surface (0-2m) and finally, the topography is almost totally flat. The upper layer of the Fleurus-Farciennes site consists of 10 m silt with poor geomechanical characteristics, overlying sands (only a few meters thick) and Westphalian shales between 15 and 20 m depth. The Westphalian shales are …
Date:
February 26, 2002
Creator:
Bell, J.; Drimmer, D.; Giovannini, A.; Manfroy, P.; Maquet, F.; Schittekat, J. et al.
Object Type:
Article
System:
The UNT Digital Library
Improvement of Safety Assessment Methodologies for Near Surface Disposal Facilities
The International Atomic Energy Agency (IAEA) Coordinated research program ''Improvement of Safety Assessment Methodologies for Near Surface Disposal Facilities'' (ISAM) has developed improved safety assessment methodology for near surface disposal facilities. The program has been underway for three years and has included around 75 active participants from 40 countries. It has also provided examples for application to three safety cases--vault, Radon type and borehole radioactive waste disposal facilities. The program has served as an excellent forum for exchange of information and good practices on safety assessment approaches and methodologies used worldwide. It also provided an opportunity for reaching broad consensus on the safety assessment methodologies to be applied to near surface low and intermediate level waste repositories. The methodology has found widespread acceptance and the need for its application on real waste disposal facilities has been clearly identified. The ISAM was finalized by the end of 2000, working material documents are available and an IAEA report will be published in 2002 summarizing the work performed during the three years of the program. The outcome of the ISAM program provides a sound basis for moving forward to a new IAEA program, which will focus on practical application of the safety assessment …
Date:
February 26, 2002
Creator:
Batandjieva, B. & Torres-Vidal, C.
Object Type:
Article
System:
The UNT Digital Library
Remediation of the Faultless Underground Nuclear Test: Moving Forward in the Face of Model Uncertainty
The Faultless underground nuclear test, conducted in central Nevada, is the site of an ongoing environmental remediation effort that has successfully progressed through numerous technical challenges due to close cooperation between the U.S. Department of Energy, (DOE) National Nuclear Security Administration and the State of Nevada Division of Environmental Protection (NDEP). The challenges faced at this site are similar to those of many other sites of groundwater contamination: substantial uncertainties due to the relative lack of data from a highly heterogeneous subsurface environment. Knowing when, where, and how to devote the often enormous resources needed to collect new data is a common problem, and one that can cause remediators and regulators to disagree and stall progress toward closing sites. For Faultless, a variety of numerical modeling techniques and statistical tools are used to provide the information needed for DOE and NDEP to confidently move forward along the remediation path to site closure. A general framework for remediation was established in an agreement and consent order between DOE and the State of Nevada that recognized that no cost-effective technology currently exists to remove the source of contaminants in nuclear cavities. Rather, the emphasis of the corrective action is on identifying the …
Date:
February 26, 2002
Creator:
Chapman, J. B.; Pohlmann, K.; Pohll, G.; Hassan, A.; Sanders, P.; Sanchez, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Modeling Transportation Resource Capacity and Optimizing Secure Shipping Operations
The Department of Energy owns a number of nuclear materials that require physical protection. This protection is required for the materials in transit as well as in storage. The resource capacity for protecting these materials in transit was allowed to decline after the end of the cold war. As Records of Decision regarding the disposition of surplus special nuclear materials (SNM) are implemented, the Department's secure transportation workload will increase dramatically. New resources cannot be added fast enough to support the growth in work scope unless secure shipping operations become more efficient. This paper describes our effort to model integrated secure shipping operations and to recommend changes to shipping plans that reduce workload and increase capacity.
Date:
February 26, 2002
Creator:
Lanthrum, G.; Jones, D. A.; Bechdel, J. & Turnquist, M. A.
Object Type:
Article
System:
The UNT Digital Library
Decommissioning Unit Cost Data
The Rocky Flats Closure Site (Site) is in the process of stabilizing residual nuclear materials, decommissioning nuclear facilities, and remediating environmental media. A number of contaminated facilities have been decommissioned, including one building, Building 779, that contained gloveboxes used for plutonium process development but did little actual plutonium processing. The actual costs incurred to decommission this facility formed much of the basis or standards used to estimate the decommissioning of the remaining plutonium-processing buildings. Recent decommissioning activities in the first actual production facility, Building 771, implemented a number of process and procedural improvements. These include methods for handling plutonium contaminated equipment, including size reduction, decontamination, and waste packaging, as well as management improvements to streamline planning and work control. These improvements resulted in a safer working environment and reduced project cost, as demonstrated in the overall project efficiency. The topic of this paper is the analysis of how this improved efficiency is reflected in recent unit costs for activities specific to the decommissioning of plutonium facilities. This analysis will allow the Site to quantify the impacts on future Rocky Flats decommissioning activities, and to develop data for planning and cost estimating the decommissioning of future facilities. The paper discusses the …
Date:
February 26, 2002
Creator:
Sanford, P. C.; Stevens, J. L. & Brandt, R.
Object Type:
Article
System:
The UNT Digital Library
Russian Technology Advancements for Waste Mixing and Retrieval
Engineers at the Mining and Chemical Combine nuclear facility, located in Zheleznogorsk, Russia, have developed a pulsating mixer/sluicer to mobilize a layer of consolidated, hardened sludge at the bottom of their 12-m-diameter by 30-m-high nuclear waste tanks. This waste has resisted mobilization by conventional sluicing jets. The new pulsating mixer/sluicer draws tank liquid into a pressure vessel, then expels it at elevated pressure either through a set of submerged mixing jets or a steerable through-air jet. Four versions (or generations) of this technology have been developed. Following testing of three other Russian mobilization and transfer systems at Pacific Northwest National Laboratory, a first generation of the new pulsating mixer/sluicer was identified for possible waste retrieval applications in U.S. high-level waste tanks (1). A second-generation pulsating mixer/sluicer was developed and successfully deployed in Tank TH-4 at the Oak Ridge Reservation, located in Tennessee, United States (2). A third-generation pulsating mixer/sluicer with a dual nozzle design was developed and is being tested for possible use by the Hanford Site's River Protection Project to retrieve waste from Tank 241-S-102, a single-shell tank containing radioactive saltcake and sludge. In cooperation with the U.S. Department of Energy Tanks Focus Area, the Mining and Chemical Combine …
Date:
February 26, 2002
Creator:
Gibbons, P. W.; Albert, T. E. & Barakov, B.
Object Type:
Article
System:
The UNT Digital Library
Los Alamos National Laboratory Tritium Technology Deployments Large Scale Demonstration and Deployment Project
This paper describes the organization, planning and initial implementation of a DOE OST program to deploy proven, cost effective technologies into D&D programs throughout the complex. The primary intent is to accelerate closure of the projects thereby saving considerable funds and at the same time being protective of worker health and the environment. Most of the technologies in the ''toolkit'' for this program have been demonstrated at a DOE site as part of a Large Scale Demonstration and Deployment Project (LSDDP). The Mound Tritium D&D LSDDP served as the base program for the technologies being deployed in this project but other LSDDP demonstrated technologies or ready-for-use commercial technologies will also be considered. The project team will evaluate needs provided by site D&D project managers, match technologies against those needs and rank deployments using a criteria listing. After selecting deployments the project will purchase the equipment and provide a deployment engineer to facilitate the technology implementation. Other cost associated with the use of the technology will be borne by the site including operating staff, safety and health reviews etc. A cost and performance report will be prepared following the deployment to document the results.
Date:
February 26, 2002
Creator:
McFee, J.; Blauvelt, D.; Stallings, E. & Willms, S.
Object Type:
Article
System:
The UNT Digital Library
Fluvial Placement of Radioactive Contaminants a Weldon Spring Case Study
The operation of the Weldon Spring Uranium Feed Materials Plant in St. Charles, MO between 1958 and 1966 resulted in the migration and emplacement of radioactive contaminants into surface water drainage systems. Multiple drainage systems, receiving from a variety of waste discharge points, combined to create unique and unexpected depositional environment. Discovery and investigation of the depositional environments was a significant technical challenge due to the complex nature of sediment movement and emplacement. The objective of this investigation was to show that application of the knowledge of geomorphic processes is an essential element of a complete stream characterization, pursuant to risk analysis and remediation. This paper sets out to describe many of the expected and unexpected findings of the investigations by the Weldon Spring Site Remedial Action Project (WSSRAP) into the placement and rework of contaminated sediments in stream systems. Information from this paper will be useful to other agencies and contractor personnel faced with the challenge of locating and quantifying contaminated sediments in seemingly haphazard fluvial depositional conditions.
Date:
February 26, 2002
Creator:
Meier, J.
Object Type:
Article
System:
The UNT Digital Library
Maine Yankee: Making the Transition from an Operating Plant to an Independent Spent Fuel Storage Installation (ISFSI)
The purpose of this paper is to describe the challenges faced by Maine Yankee Atomic Power Company in making the transition from an operating nuclear power plant to an Independent Spent Fuel Storage Installation (ISFSI). Maine Yankee (MY) is a 900-megawatt Combustion Engineering pressurized water reactor whose architect engineer was Stone & Webster. Maine Yankee was put into commercial operation on December 28, 1972. It is located on an 820-acre site, on the shores of the Back River in Wiscasset, Maine about 40 miles northeast of Portland, Maine. During its operating life, it generated about 1.2 billion kilowatts of power, providing 25% of Maine's electric power needs and serving additional customers in New England. Maine Yankee's lifetime capacity factor was about 67% and it employed more than 450 people. The decision was made to shutdown Maine Yankee in August of 1997, based on economic reasons. Once this decision was made planning began on how to accomplish safe and cost effective decommissioning of the plant by 2004 while being responsive to the community and employees.
Date:
February 26, 2002
Creator:
Norton, W. & McGough, M. S.
Object Type:
Article
System:
The UNT Digital Library
Integrated Pilot Plant for a Large Cold Crucible Induction Melter
COGEMA has been vitrifying high-level liquid waste produced during nuclear fuel reprocessing on an industrial scale for over 20 years, with two main objectives: containment of the long lived fission products and reduction of the final volume of waste. Research performed by the French Atomic Energy Commission (CEA) in the 1950s led to the selection of borosilicate glass as the most suitable containment matrix for waste from spent nuclear fuel and to the development of the induction melter technology. This was followed by the commissioning of the Marcoule Vitrification Facility (AVM) in 1978. The process was implemented at a larger scale in the late 1980s in the R7 and T7 facilities of the La Hague reprocessing plant. COGEMA facilities have produced more than 11,000 high level glass canisters, representing more than 4,500 metric tons of glass and 4.5 billion curies. To further improve the performance of the vitrification lines in the R7 and T7 facilities, the CEA and COGEMA have been developing the Cold Crucible Melter (CCM) technology since the 1980s. This technology benefits from the 20 years of COGEMA HLW vitrification experience and ensures a virtually unlimited equipment service life and extensive flexibility in dealing with different types of …
Date:
February 26, 2002
Creator:
Do Quang, R.; Jensen, A.; Prod'homme, A.; Fatoux, R. & Lacombe, J.
Object Type:
Article
System:
The UNT Digital Library
Scenario Development Methodology for Performance Assessment of Near-surface LILW Repository based on FEPs and Interaction Matrix Approach
Systematic procedure of developing radionuclide release scenarios was established based on FEP list and Interaction Matrix for the near-surface LILW repository. The relevant FEPs were screened by experts' review in terms of domestic situation and combined into scenarios on the basis of Interaction Matrix analysis. A computer program named IMFEP{sub NS} was developed to view and select project FEPs, to make its Interaction Matrix at user's disposal, and to visualize the interaction between FEPs and Interaction Matrix. The concept of approach to generate scenarios for entire domain is to divide the whole system domain into three sections: Near-field, Far-field, and Biosphere. Possible sub-scenarios were generated within each sectional subscenario set composed by assembling relevant FEPS and Interaction Matrix in advance, and then scenarios for entire system were built up with sub-scenarios of each section. As an application of established scenario generation approach, sixteen design scenarios and two alternative scenarios for near-surface repository were evaluated. Finally, a reference scenario and other noteworthy scenarios were selected through experts' scenario screening.
Date:
February 26, 2002
Creator:
Park, J. W.; Kim, C. L.; Chang, K. M. & Song, M. J.
Object Type:
Article
System:
The UNT Digital Library
A Benchmarking Analysis for Five Radionuclide Vadose Zone Models (Chain, Multimed{_}DP, Fectuz, Hydrus, and Chain 2D) in Soil Screening Level Calculations
Five vadose zone models with different degrees of complexity (CHAIN, MULTIMED{_}DP, FECTUZ, HYDRUS, and CHAIN 2D) were selected for use in radionuclide soil screening level (SSL) calculations. A benchmarking analysis between the models was conducted for a radionuclide ({sup 99}Tc) release scenario at the Las Cruces Trench Site in New Mexico. Sensitivity of three model outputs to the input parameters were evaluated and compared among the models. The three outputs were peak contaminant concentrations, time to peak concentrations at the water table, and time to exceed the contaminants maximum critical level at a representative receptor well. Model parameters investigated include soil properties such as bulk density, water content, soil water retention parameters and hydraulic conductivity. Chemical properties examined include distribution coefficient, radionuclide half-life, dispersion coefficient, and molecular diffusion. Other soil characteristics, such as recharge rate, also were examined. Model sensitivity was quantified in the form of sensitivity and relative sensitivity coefficients. Relative sensitivities were used to compare the sensitivities of different parameters. The analysis indicates that soil water content, recharge rate, saturated soil water content, and soil retention parameter, {beta}, have a great influence on model outputs. In general, the results of sensitivities and relative sensitivities using five models are …
Date:
February 26, 2002
Creator:
Chen, J-S.; Drake, R.; Lin, Z. & Jewett, D. G.
Object Type:
Article
System:
The UNT Digital Library
Handling and Treatment of Uranium Contaminated Combustible Radioactive Low Level Waste (LLW)
Studsvik RadWaste in Sweden has many years of experience in handling of low-level radioactive waste, such as burnable waste for incineration and scrap metal for melting. In Erwin, TN, in the USA, Studsvik Inc also operates a THOR (pyrolysis) facility for treatment of various kinds of ion-exchange resins. The advantage of incineration of combustible waste as well as of ion-exchange resins by pyrolysis, is the vast volume reduction which minimizes the cost for final storage and results in an inert end-product which is feasible for safe final disposal. The amount of uranium in the incinerable waste has impact on the quality of the resulting ash. The quality improves with lower U-content. One way of reducing the Ucontent is leaching using a chemical process before and if necessary also after the incineration. Ranstad Mineral AB has been established in the 1960s to support the Swedish national program for uranium mining in southern Sweden. Ranstad Mineral works among others wit h chemical processes to reduce uranium content by leaching. During 1998-2000 about 150 tons/year have been processed. The goal was to reach uranium residues of less than 0.02% for disposal on the municipal waste disposal.
Date:
February 26, 2002
Creator:
Lorenzen, J,; Lindberg, M. & Luvstrand, J.
Object Type:
Article
System:
The UNT Digital Library
Processing of the MCC K26 Plutonium-Bearing Sludges to Recover Weapons-Grade Plutonium That is Not Under any Treaty or Monitoring Agreement
Russian Federation (RF) and United States (US) collaborations from July 1998 through July 2001 conducted investigations of the Pu-bearing sludges in storage at the Mining Chemical Combine (MCC) K-26 site in order to dispose of weapons-grade plutonium and decommission the radiochemical plant. This RF work resulted in the recovery of approximately 20 kg of weapons-grade plutonium (and {approx}19 MT of uranium) from the sludges which was stored as oxide. Another method investigated and partially developed as joint collaborative efforts during this time period was direct immobilization of plutonium with no recovery of plutonium. This method melts the untreated recovered sludges by microwave ultrahigh frequency (UHF) heating with glass formers. After cooling, melter-crucibles of vitrified sludge are stored on site in underground cavities for eventual disposal in a geologic repository. Cost and technical feasibility studies of the two methods show that direct immobilization (i.e., vitrification)of the plutonium-containing sludge is the preferred alternative. It is also preferred from the ecological point of view. However, RF funding alone is insufficient to continue this work, and US funding has been suspended. It appears unlikely that development of full scale vitrification technologies for the plutonium-bearing sludges can be undertaken without continuing support from the US …
Date:
February 26, 2002
Creator:
Jardine, L. J.; Kudinov, K. G.; Tretyakov, A. A.; Bondin, V. V.; Sorokin, Y. P.; Manakova, L. F. et al.
Object Type:
Article
System:
The UNT Digital Library
Salt Processing at the Savannah River Site: Results of Technology Down-Selection and Research and Development to Support New Salt Waste Processing Facility
The Department of Energy's (DOE) Savannah River Site (SRS) high-level waste (HLW) program is responsible for storage, treatment, and immobilization of HLW for disposal. The Salt Processing Project (SPP) is the salt waste (water-soluble) treatment portion of this effort. The overall SPP encompasses the selection, design, construction, and operation of technologies to prepare the salt-waste feed material for immobilization at the site's Saltstone Production Facility (SPF) and vitrification facility (Defense Waste Processing Facility [DWPF]). Major constituents that must be removed from the salt waste and sent as feed to DWPF include cesium (Cs), strontium (Sr), and actinides. In April 2000, the DOE Deputy Secretary for Project Completion (EM-40) established the SRS Salt Processing Project Technical Working Group (TWG) to manage technology development of treatment alternatives for SRS high-level salt wastes. The separation alternatives investigated included three candidate Cs-removal processes selected, as well as actinide and Sr removal that are also required as a part of each process. The candidate Cs-removal processes are: crystalline Silicotitanate Non-Elutable Ion Exchange (CST); caustic Side Solvent Extraction (CSSX); and small Tank Tetraphenylborate Precipitation (STTP). The Tanks Focus Area was asked to assist DOE by managing the SPP research and development (R&D), revising roadmaps, and developing …
Date:
February 26, 2002
Creator:
Lang, K.; Gerdes, K.; Picha, K.; Spader, W.; McCullough, J.; Reynolds, J. et al.
Object Type:
Article
System:
The UNT Digital Library
Emptying of the Storage for Solid Radioactive Waste in the Greifswald Nuclear Power Plant
On the Greifswald site, 8 WWER 440 reactor units are located and also several facilities to handle fuel and radwaste. After the reunification of Germany, the final decision was taken to decommission all these Russian designed reactors. Thus, EWN is faced with a major decommissioning project in the field of nuclear power stations. One of the major tasks before the dismantling of the plant is the complete disposal of the operational waste. Among other facilities, a store for solid radioactive waste is located on the site, which has been filled over 17 years of operation of units 1 to 4. The paper presents the disposal technology development and results achieved. This activity is the first project in the operational history of the Russian type serial reactor line WWER-440.
Date:
February 26, 2002
Creator:
Hartmann, B. & Fischer, J.
Object Type:
Article
System:
The UNT Digital Library