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Native American Concerns and State of California Low-Level Radioactive Waste Disposal Facility: Mohave, Navajo, Chemehuevi, and Nevada Paiute ResponsesStoffle, Richard W., Evans, Michael, Jensen, Florence January 1987 (has links)
This report describes the results of an ethnographic study performed by Cultural Systems Research, Incorporated (CSRI) for US Ecology, Inc. The study was part of US Ecology's efforts to select a site for the disposal of Low Level Radioactive Waste (LLRW) for the State of California. Dr. Stoffle and his research team were responsible for conducting the Mohave, Navajo, and Southern Paiute portions of the study.
This draft report includes information that was not included in the final report such as hand drawn maps produced during interviews with tribal representatives. This project marked the first time that Richard Stoffle and his team used mapping as a means to document places and areas of cultural significance.
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Dissolution of copper and leaching of borosilicate waste glass in solutions synthesizing groundwatersBurda, Pamela, 1956- January 1989 (has links)
Samples of ordinary copper, hot-isotactically-pressed (HIP) copper, and simulated borosilicate high-level waste glass were leached at 25°C, 51°C, and 80°C in solutions simulating brine and silicate groundwaters. It was found that the amount of glass leached increased at higher temperatures, and more leaching occurred in brine than in silicate groundwater. This behavior is predicted by Le Chatelier's Principle. Similarly, more copper was dissolved at higher temperatures, and more was dissolved in brine than in silicate groundwaters.
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Desenvolvimento de método para caracterização de embalados de rejeitos radioativos / Development of a method for the radioisotopic characterization of waste packagesSouza, Daiane Cristini Barbosa de 16 September 2013 (has links)
Atualmente, a caracterização dos resíduos radioativos gerados na operação do reator nuclear de pesquisas IEA-R1 está em curso. O reator IEA-R1 é um reator do tipo piscina aberta, moderado e refrigerado por água leve, utilizando dois leitos de resinas de troca iônica e de carvão ativado para purificação de água de refrigeração. Estes meios filtrantes são substituídos quando já não são capazes de manter a qualidade da água dentro dos limites exigidos e são tratados como rejeitos radioativos. Contendo produtos de fissão, ativação e actinídeos que escapam do núcleo do reator para a água da piscina, apresentam altas taxas de dose devido à quantidade de emissores gama de meias-vidas curtas e intermediárias, emissores alfa, elementos transurânicos de meia-vida longa bem como emissores beta puros. A caracterização destes rejeitos, consequentemente, requer métodos de análise radioquímica que incluem a amostragem e o processamento das amostras, resultando em doses elevadas para os trabalhadores. Nesse contexto, o objetivo deste trabalho consistiu em correlacionar os resultados das análises radioquímicas de amostras de rejeitos, com os resultados das medições radiométricas, utilizando a modelagem das taxas de dose em diferentes distâncias da superfície dos embalados. As taxas de dose medidas foram comparadas com os resultados de cálculos . Massa, volume e geometria das fases sólidas e líquidas de cada um dos tambores também foram determinadas, uma vez que o teor de água varia amplamente entre diferentes tambores, e são essenciais para estimar as atividades totais em cada tambor. / The characterization of the radioactive wastes generated in the operation of the nuclear research reactor IEA-R1 is currently ongoing. The IEA-R1 is an open pool type reactor, moderated and cooled by light water that uses two beds of ion-exchange resins and activated charcoal to remove impurities from the cooling water. These filter media are replaced when they are no longer able to maintain water quality within the required limits and are treated as radioactive waste. They contain the actinides and the fission and activation products that leaked into the reactor pool water. They give off high dose rates due to the amount of gamma-emitters present and are a long-term radiation safety concern because of their content of long-lived alpha- and beta-emitters. The characterization of these wastes requires radiochemical analysis methods, which include the sampling and processing of samples, resulting in high exposure to the workers. The objective of this study was to correlate the results of activity concentrations obtained in previous radiochemical analyses with the results of measurements of dose rates at various distances from the package surfaces, aiming at reducing the exposure of personnel by avoiding more sampling and sample analysis operations. Mass, volume and geometry of solid and liquid phases of each drum, which vary widely among different drums, were also estimated and use to determine total activity. The measured and calculated dose rates were compared to confirm the activity estimates.
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Desenvolvimento de um método para gerenciamento de rejeitos radioativos no laboratório de produção de fontes de iodo-125 utilizadas em braquiterapia / Development of a method for radioactive waste management in sources production laboratory iodine-125 used in brachytherapySouza, Daiane Cristini Barbosa de 21 May 2018 (has links)
A braquiterapia é um tratamento clínico que consiste na aplicação de fontes radioativas seladas em certos tipos de tumores. Atualmente, está em fase de implantação o laboratório para produção de fontes de 125I a fim de nacionalizar a produção de fontes para reduzir os custos na sua aplicação e atender a demanda da população brasileira. A tese defendida neste trabalho é o desenvolvimento de um método para o gerenciamento de rejeitos radioativos que serão gerados ao longo da produção dessas fontes. A metodologia aplicada consistiu na criação de etapas de gerenciamento de rejeitos radioativos aplicadas ao 125I que contemplasse o gerenciamento na própria instalação produtora. Os rejeitos radioativos que serão gerados ao longo de todo processo de fabricação das fontes de 125I serão produzidos dentro de três células estanques, localizadas dentro do laboratório. Para cada um dos cenários foram relacionados os rejeitos sólidos, líquidos e gasosos gerados em cada uma das três células de produção. Para rejeitos sólidos e líquidos foram estimados: volume, massa, taxa de entrada no depósito inicial e tempo para liberação em meio ambiente. Para rejeitos gasosos foi estimado: taxa de volatilização do 125I e metodologia para medição dos filtros de carvão ativado. Os resultados apresentados permitem concluir que o laboratório tem condições de realizar o gerenciamento dos rejeitos que produzirá. Implantar um sistema de gerenciamento dentro do próprio laboratório, aperfeiçoará as atividades rotineiras e o licenciamento junto a CNEN. / Brachytherapy is a clinical treatment that consists of the application of sealed radioactive sources in certain types of tumors. The laboratory for the production of 125I sources is currently being implemented in order to nationalize the production of sources to reduce the costs of its application and to meet the demand of the Brazilian population. The thesis defended in this work is the development of a method for the management of radioactive waste that will be generated during the production of these sources. The applied methodology consisted in the creation of steps of management of radioactive waste applied to 125I that contemplated the management in the own production facility. The radioactive wastes that will be generated throughout the manufacturing process of 125I sources will be produced within three sealed cells located inside the laboratory. For each of the scenarios the solid, liquid and gaseous wastes generated in each of the three production cells were related. For solid and liquid wastes were estimated: volume, mass, rate of entry into the initial deposit and time for release into the environment. For gaseous rejects it was estimated: 125I volatilization rate and methodology for the measurement of activated carbon filters. The results presented allow us to conclude that the laboratory is able to perform the management of the wastes it will produce. Implementing a management system within the laboratory, will improve routine activities and licensing with CNEN.
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Modelling of high-energy radiation damage in materials relevant to nuclear and fusion energyZarkadoula, Evangelia January 2013 (has links)
The objective through my PhD has been to investigate radiation damage effects in materials related to fusion and to safe encapsulation of nuclear waste, using Molecular Dynamics (MD) methods. Particularly, using MD, we acquire essential information about the multi-scale phenomena that take place during irradiation of materials, and gain access at length and time-scales not possible to access experimentally. Computer simulations provide information at the microscopic level, acting as a bridge to the experimental observations and giving insights into processes that take place at small time and length-scales. The increasing computer capabilities in combination with recently developed scalable codes, and the availability of realistic potentials set the stage to perform large scale simulations, approaching phenomena that take place at the atomistic and mesoscopic scale (fractions of m for the first time) in a more realistic way. High-energy radiation damage effects have not been studied previously, yet it is important to simulate and reveal information about the properties of the materials under extreme irradiation conditions. Large scale MD simulations provide a detailed description of microstructural changes. Understanding of the primary stage of damage and short term annealing (scale of tens of picoseconds) will lead to better understanding of the materials properties, best possible long-term use of the materials and, importantly, new routes of optimization of their use. Systems of interest in my research are candidate fusion reactor structural materials (iron and tungsten) and materials related to the radioactive waste management (zirconia). High-energy events require large simulation box length in order for the damage to be contained in the system. This was a limitation for previous simulations, which was recently shifted with my radiation damage MD simulations. For the first time high-energy radiation damage effects were simulated, approaching new energy and length scales, giving a more realistic view of processes related to fusion and to high-energy ion irradiation of material.
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Aplicação de biossorventes no tratamento de rejeitos radioativos líquidos / Application of biosorbents in treatment of the radioactive liquid wasteFerreira, Rafael Vicente de Padua 20 February 2014 (has links)
Rejeitos radioativos líquidos contendo compostos orgânicos precisam de atenção especial, porque os processos de tratamento disponíveis são caros e difíceis de serem gerenciados. A biossorção é uma potencial técnica de tratamento que tem sido estudada em rejeitos simulados. O termo biossorção é utilizado para descrever a remoção de metais, metalóides e/ou radionuclídeos por um material de origem biológica independentemente de sua atividade metabólica. Dentre as potenciais biomassas, os resíduos agrícolas apresentam características muito atraentes, pois possibilitam a remoção dos radionuclídeos presentes no rejeito utilizando um biossorvente de baixo custo. O objetivo deste estudo foi avaliar o uso potencial de diferentes biomassas originadas de produtos ou resíduos agrícolas (fibra de coco, casca de café e casca de arroz) no tratamento de rejeitos radioativos líquidos orgânicos reais. Foram realizados experimentos com essas biomassas incluindo i) Preparação, ativação e caracterização das biomassas; ii) Realização dos ensaios de biossorção e iii) Avaliação do produto da imobilização de biomassas em cimento. As biomassas foram testadas nas formas brutas e ativadas. A ativação foi realizada com soluções diluídas de HNO3 e NaOH. Os ensaios de biossorção foram realizados em frascos de polietileno, nos quais foram adicionados 10 mL do rejeito radioativo ou diluições do rejeito em água deionizada com o mesmo pH e 2 % da biomassa (m/v). No final do experimento, a biomassa foi separada por filtração e a concentração dos radioisótopos remanescente no filtrado foi determinada por ICP-OES e espectrometria gama. O rejeito estudado contém urânio natural (U (total)), amerício-241 e césio-137. Os tempos de contato adotados foram 30 min, 1, 2 e 4 horas e as concentrações estudadas variaram entre 10% e 100%. Os resultados foram avaliados por meio da capacidade máxima de sorção experimental e modelos ternários de isotermas e cinética. As maiores capacidades de sorção foram observadas com casca de café bruta, com valores aproximados de 2 mg/g de U (total), 40 x10-6 mg/g de Am-241 e 50 x10-9 mg/g de Cs-137 e, também, com fibra de coco ativada, com valores de 2 mg/g de U (total), 70 x10-6 mg/g de Am-241 e 40 x10-9 mg/g de Cs-137. As propriedades avaliadas na determinação da qualidade do produto de imobilização foram água livre, resistência mecânica, trabalhabilidade e tempo de pega. Os melhores produtos de imobilização para estas biomassas foram obtidos com uma relação água/cimento de 0,30, contendo 5%, 10% e 15% de casca café bruto, fibra de coco ativada e casca de café ativado, respectivamente. Estes resultados sugerem que a biossorção com casca de café bruta e fibra de coco sob a forma ativada podem ser aplicadas no tratamento de rejeitos radioativos líquidos orgânicos contendo urânio, amerício-241 e césio-137. / Radioactive liquid waste containing organic compounds need special attention, because the treatment processes available are expensive and difficult to manage. The biosorption is a potential treatment technique that has been studied in simulated wastes. The biosorption term is used to describe the removal of metals, non-metals and/or radionuclides by a material from a biological source, regardless of its metabolic activity. Among the potential biomass, agricultural residues have very attractive features, as they allow for the removal of radionuclides present in the waste using a low cost biosorbent. The aim of this study was to evaluate the potential use of different biomass originating from agricultural products (coconut fiber, coffee husk and rice husk) in the treatment of real radioactive liquid organic waste. Experiments with these biomasses were made including i) Preparation, activation and characterization of biomasses; ii) Conducting biosorption assays; and iii) Evaluation of the product of immobilization of biomasses in cement. The biomasses were tested in raw and activated forms. The activation was carried out with diluted HNO3 and NaOH solutions. Biosorption assays were performed in polyethylene bottles, in which were added 10 mL of radioactive waste or waste dilutions in deionized water with the same pH and 2% of the biomass (w/v). At the end of the experiment, the biomass was separated by filtration and the remaining concentration of radioisotopes in the filtrate was determined by ICP-OES and gamma spectrometry. The studied waste contains natural uranium, americium-241 and cesium-137. The adopted contact times were 30 min, 1, 2 and 4 hours and the concentrations tested ranged between 10% and 100%. The results were evaluated by maximum experimental sorption capacity and isotherm and kinetics ternary models. The highest sorption capacity was observed with raw coffee husk, with approximate values of 2 mg/g of U (total), 40 x10-6 mg/g of Am-241 and 50 x10-9 mg/g of Cs-137 and, also, with activated coconut fiber, with values of 2 mg/g of U (total), 70 x10-6 mg/g of Am-241 and 40 x10-9 mg/g of Cs-137. The properties evaluated to determine the quality of the immobilization product were free water, mechanical strength, workability and setting time. The best immobilization products for these biomasses were obtained with a water/cement ratio of 0.30, containing 5%, 10% and 15% of raw coffee husk, activated coconut fiber and activated raw coffee husk, respectively. These results suggest that biosorption with raw coffee husk and activated coconut fiber can be applied in the treatment of radioactive liquid organic wastes containing uranium, americium-241 and cesium-137.
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Aplicação de biossorventes no tratamento de rejeitos radioativos líquidos / Application of biosorbents in treatment of the radioactive liquid wasteRafael Vicente de Padua Ferreira 20 February 2014 (has links)
Rejeitos radioativos líquidos contendo compostos orgânicos precisam de atenção especial, porque os processos de tratamento disponíveis são caros e difíceis de serem gerenciados. A biossorção é uma potencial técnica de tratamento que tem sido estudada em rejeitos simulados. O termo biossorção é utilizado para descrever a remoção de metais, metalóides e/ou radionuclídeos por um material de origem biológica independentemente de sua atividade metabólica. Dentre as potenciais biomassas, os resíduos agrícolas apresentam características muito atraentes, pois possibilitam a remoção dos radionuclídeos presentes no rejeito utilizando um biossorvente de baixo custo. O objetivo deste estudo foi avaliar o uso potencial de diferentes biomassas originadas de produtos ou resíduos agrícolas (fibra de coco, casca de café e casca de arroz) no tratamento de rejeitos radioativos líquidos orgânicos reais. Foram realizados experimentos com essas biomassas incluindo i) Preparação, ativação e caracterização das biomassas; ii) Realização dos ensaios de biossorção e iii) Avaliação do produto da imobilização de biomassas em cimento. As biomassas foram testadas nas formas brutas e ativadas. A ativação foi realizada com soluções diluídas de HNO3 e NaOH. Os ensaios de biossorção foram realizados em frascos de polietileno, nos quais foram adicionados 10 mL do rejeito radioativo ou diluições do rejeito em água deionizada com o mesmo pH e 2 % da biomassa (m/v). No final do experimento, a biomassa foi separada por filtração e a concentração dos radioisótopos remanescente no filtrado foi determinada por ICP-OES e espectrometria gama. O rejeito estudado contém urânio natural (U (total)), amerício-241 e césio-137. Os tempos de contato adotados foram 30 min, 1, 2 e 4 horas e as concentrações estudadas variaram entre 10% e 100%. Os resultados foram avaliados por meio da capacidade máxima de sorção experimental e modelos ternários de isotermas e cinética. As maiores capacidades de sorção foram observadas com casca de café bruta, com valores aproximados de 2 mg/g de U (total), 40 x10-6 mg/g de Am-241 e 50 x10-9 mg/g de Cs-137 e, também, com fibra de coco ativada, com valores de 2 mg/g de U (total), 70 x10-6 mg/g de Am-241 e 40 x10-9 mg/g de Cs-137. As propriedades avaliadas na determinação da qualidade do produto de imobilização foram água livre, resistência mecânica, trabalhabilidade e tempo de pega. Os melhores produtos de imobilização para estas biomassas foram obtidos com uma relação água/cimento de 0,30, contendo 5%, 10% e 15% de casca café bruto, fibra de coco ativada e casca de café ativado, respectivamente. Estes resultados sugerem que a biossorção com casca de café bruta e fibra de coco sob a forma ativada podem ser aplicadas no tratamento de rejeitos radioativos líquidos orgânicos contendo urânio, amerício-241 e césio-137. / Radioactive liquid waste containing organic compounds need special attention, because the treatment processes available are expensive and difficult to manage. The biosorption is a potential treatment technique that has been studied in simulated wastes. The biosorption term is used to describe the removal of metals, non-metals and/or radionuclides by a material from a biological source, regardless of its metabolic activity. Among the potential biomass, agricultural residues have very attractive features, as they allow for the removal of radionuclides present in the waste using a low cost biosorbent. The aim of this study was to evaluate the potential use of different biomass originating from agricultural products (coconut fiber, coffee husk and rice husk) in the treatment of real radioactive liquid organic waste. Experiments with these biomasses were made including i) Preparation, activation and characterization of biomasses; ii) Conducting biosorption assays; and iii) Evaluation of the product of immobilization of biomasses in cement. The biomasses were tested in raw and activated forms. The activation was carried out with diluted HNO3 and NaOH solutions. Biosorption assays were performed in polyethylene bottles, in which were added 10 mL of radioactive waste or waste dilutions in deionized water with the same pH and 2% of the biomass (w/v). At the end of the experiment, the biomass was separated by filtration and the remaining concentration of radioisotopes in the filtrate was determined by ICP-OES and gamma spectrometry. The studied waste contains natural uranium, americium-241 and cesium-137. The adopted contact times were 30 min, 1, 2 and 4 hours and the concentrations tested ranged between 10% and 100%. The results were evaluated by maximum experimental sorption capacity and isotherm and kinetics ternary models. The highest sorption capacity was observed with raw coffee husk, with approximate values of 2 mg/g of U (total), 40 x10-6 mg/g of Am-241 and 50 x10-9 mg/g of Cs-137 and, also, with activated coconut fiber, with values of 2 mg/g of U (total), 70 x10-6 mg/g of Am-241 and 40 x10-9 mg/g of Cs-137. The properties evaluated to determine the quality of the immobilization product were free water, mechanical strength, workability and setting time. The best immobilization products for these biomasses were obtained with a water/cement ratio of 0.30, containing 5%, 10% and 15% of raw coffee husk, activated coconut fiber and activated raw coffee husk, respectively. These results suggest that biosorption with raw coffee husk and activated coconut fiber can be applied in the treatment of radioactive liquid organic wastes containing uranium, americium-241 and cesium-137.
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The effects of weathering and diagenetic processes on the geochemical stability of uranium mill tailingsSinclair, Gregory January 2004 (has links)
Uranium mill tailings from the Ranger mine, located in the Alligator Rivers Region of the Northern Territory, Australia, were examined to assess the effects of weathering and diagenesis on their long-term geochemical stability. Run of mill uranium tailings are a complex heterogeneous mixture of lithogenic ( primary gangue minerals and weathering products ) and secondary ( components that form during milling ) minerals, residual process chemicals and biogenic ( products of biological activity ) phases. Following transfer to the tailings storage facility, post depositional reactions alter the mineralogical and hydrochemical characteristics of the tailings solids and pore waters in accordance with weathering and diagenetic processes. In this thesis, a detailed examination of tailings cores and pore waters, kinetic column test work and geochemical modelling was combined with results from earlier studies to examine the key processes governing the geochemical stability of the Ranger tailings. Conclusions drawn from the work clearly demonstrates that the solid state speciation and mobility of metals and radionuclides in the tailings pile are governed by the processes of oxidative dissolution of sulfide minerals, weathering of phyllosilicates and organic matter diagenesis. The processes are spatially dependent, evolve over time and are influenced by the following key factors : 1. Tailings water content or degree of saturation ; 2. The nature and content of organic matter in the tailings ; 3. Redox potential of the tailings solid - pore water interface ; and 4. The specific reactivity of precursor minerals ( primary / secondary ) from the milling process and pore water solutes. Combined, these processes lead to the formation of authigenic minerals, which control the solubility of pore water constituents. These mechanisms will also have a profound impact on the long-term geochemical stability of the tailings pile and, as such, will need to be taken into account in the design, management and closure of the final tailings repositories at the Ranger site. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2004.
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Kampanjmottagande : Hur tas Regionförbundet i Kalmar läns kampanj om slutförvar av använt kränbränsle emot av målgruppen?Franzén, Jonas, Kautto, Jim January 2009 (has links)
<p>Authors: Jonas Franzén and Jim Kautto</p><p>Title: Information campaign analysis of the Region Council of Kalmar Counties public information campaign about final storage of radioactive waste.</p><p>Level: BA Thesis in Media and Communication Studies.</p><p>Key words: Campaign, Campaign analysis, final storage of radioactive waste, Region Council.</p><p>Language: Swedish</p><p>Content: The Regional Council of Kalmar County launched a campaign about final storage of radioactive waste in the spring of 2009. This study analyzes how that campaign was received by the target group.</p><p>Theory: Following theories have been used in the study; theories of communication, planning of communication, public campaigns and receptions studies.</p><p>Method: Methods used in this study is observing people passing the exhibition, asking questions to people passing the exhibition and two focus groups. We also asked questions to people riding the bus where the commercial was shown. Finally we got background information from two interviews with the creators of the campaign.</p><p>Results: The campaign was launched based on a political decision. Despite that the decision was vague and that the Region Council was lacking a clear objective and measureable goals, the campaign still came out as a success. Since the objective with the campaign was to broaden the dialogue regarding final storage of radioactive waste, and make the public more informed about what could happen in Oskarshamn if the final storage comes there, the campaign succeeded in waken up some interest from the public opinion. The studies could not determine whether the campaign decreased the public's worries about the final storage of radioactive waste or not.</p><p>Number of pages: 49 + appendix</p><p>Program: Program for International Communication</p><p>Location: University of Kalmar</p><p>Institution: Institution of Communication and Design</p><p>Period: Spring of 2009</p><p>Tutor: Sara Hamqvist</p><p>Examiner: Britt-Marie Ringfjord</p>
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Monte Carlo MDA determination for waste drum sourcesBuchholz, Matthew A. 16 October 2001 (has links)
Past weapons production activities have resulted in mass quantities of trans-uranic
waste being buried in drums at several sites in the United States. In an effort to
relocate these waste drums to more permanent storage sites, Fluor Hanford has
begun characterizing their contents to ensure compliance with various shipping and
storage requirements. Non-destructive analysis techniques are regularly employed,
among them passive radiation detection using a Canberra Gamma-Energy-Analyzer
germanium detector vault. Necessary strict legal tolerances require strong quality
assurance. The detectors are frequently calibrated in the traditional method with
check sources, but it would be advantageous to have an estimate of system
minimum detectable activity (MDA). However, any estimate is complicated by the
fact that sources are distributed stochastically in the waste drums.
In this study, a method was developed to predict system detector efficiency for a
variety of detector configurations and drum fill materials and calculate MDA based
on these efficiencies. The various system designs were modeled in Monte Carlo
N-Particle Code, version 4b, to determine photopeak detection efficiency. An
external code written in C programming language was used to randomly assign
between one and 20 sources to volumetric regions of the waste drum. Twenty
simulations were performed for each design and drum fill material combination,
each time redefining the stochastically distributed source. This provided a
normally distributed spectrum of 20 efficiencies for each situation. From this,
mean and lower 95% confidence limit efficiencies were used to calculate MDA.
The patterns among the results were then compared with values predicted by the
MDA formula. Finally, an examination was made of the impact on the MDA of the
system's true design in the case of single or multiple detector failure.
The results indicate that this method of estimating minimum detectable activity,
although costly in computing time, provides results consistent with intuitive and
calculated expectations. Future work would allow easy calibration of the model to
measured efficiency results. Used in coordination with physical experiments, this
method may eventually prove useful in benchmarking system performance and
accurately ensuring reliable waste drum characterizations. / Graduation date: 2003
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